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Title: Retinal metabolic abnormalities in diabetic mouse: comparison with diabetic rat. Abstract: PURPOSE: Dogs and rats are commonly used to examine the pathogenesis of diabetic retinopathy, but mouse is sparingly studied as an animal model of diabetic retinopathy. In this study metabolic abnormalities, postulated to contribute to the development of retinopathy in diabetes, are investigated in the retina of mice diabetic or galactose-fed for 2 months, and are compared to those obtained from hyperglycemic rats. METHODS: Diabetes was induced in mice (C57BL/6) and rats (Sprague Dawley) by alloxan injection, and experimental galactosemia by feeding normal animals diets supplemented with 30% galactose. After 2 months of hyperglycemia, levels of lipid peroxides, glutathione, nitric oxides and sorbitol, and activities of protein kinase C and (Na-K)-ATPase were measured in the retina. RESULTS: Two months of diabetes or experimental galactosemia in mice increased retinal oxidative stress, PKC activity and nitric oxides by 40-50% and sorbitol levels by 3 folds, and these abnormalities were similar to those observed in the retina of rats hyperglycemic for 2 months. CONCLUSIONS: Metabolic abnormalities, which are postulated to play important role in the development of diabetic retinopathy in other animal models, are present in the retina of diabetic mice, and the level of metabolic abnormalities is very comparable between mice and rats. Thus, mouse seems to be a promising animal model to study the pathogenesis of diabetic retinopathy.

Title: Spatially resolved changes in diabetic rat skeletal muscle metabolism in vivo studied by 31P-n.m.r. spectroscopy. Abstract: Phase-modulated rotating-frame imaging (p.m.r.f.i.), a localization technique for 31P-n.m.r. spectroscopy, has been applied to obtain information on the heterogeneity of phosphorus-containing metabolites and pH in the skeletal muscle of control and streptozotocin-diabetic rats. Using this method, the metabolic changes in four spatially resolved longitudinal slices (where slice I is superficial and slice IV is deep muscle) through the ankle flexor muscles have been investigated at rest and during steady-state isometric twitch-contraction at 2 Hz. At rest, intracellular pH was lower, and phosphocreatine (PCr)/ATP was higher, throughout the muscle mass in diabetic compared with control animals. The change in PCr/ATP in diabetic muscle correlated with a decrease in the chemically determined ATP concentration. During the muscle stimulation period, the decrease in pH observed in diabetic muscle at rest was maintained, but not exacerbated, by the contractile stimulus. Stimulation of muscle contraction caused more marked changes in PCr/(PCr + Pi), PCr/ATP and Pi/ATP in the diabetic group. These changes were most evident in slice III, which contains the greatest proportion of fast glycolytic-oxidative (type IIa) fibres, in which statistically significant differences were observed for all metabolite ratios. The results presented suggest that some degree of heterogeneity occurs in diabetic skeletal muscle in vivo with respect to the extent of metabolic dysfunction caused by the diabetic insult and that regions of the muscle containing high proportions of type IIa fibres appear to be most severely affected.

Title: Mitochondria respiration and susceptibility to ischemia-reperfusion injury in diabetic hearts. Abstract: Cardiovascular complications are the primary cause of death for diabetic patients. Clinical and experimental observation has showed the development of dysfunctional cardiomyopathy as one of the main complications of diabetes. Whether the cardiomyopathy results from an increased susceptibility of cardiac tissue to ischemic insult or from a specific functional defect of cardiac mitochondria is a controversial issue. The investigation of possible functional defect in cardiac mitochondria from diabetic rats indicates a decline in state 3 respiration only in animals presenting a marked decrease in body weight. Mitochondria from rats presenting a level of hyperglycemia similar to diabetic animals but not the marked weight loss typical of the latter group show no decline in state 3 respiration, the values being indistinguishable from those of control mitochondria. Mitochondria from hyperglycemic rats, however, show a 15-20% increase in state 4 oxygen consumption but only when glutamate is used as energetic substrate, as compared to a 40-50% increase in state 4 respiration in mitochondria from diabetic rats under similar experimental conditions. This phenomenon is unrelated to diabetes duration, as it is observed at 2 as well as 8 weeks after diabetes onset. Taken together, these data argue against hyperglycemia per se being a direct cause of the decline in state 3 oxygen consumption observed in cardiac mitochondria of type-I diabetic rats and indicate that differences exist in cardiac mitochondrial function in rats generically labeled as diabetic. These differences can contribute to explain discrepancies in experimental results reported by various groups in the field and provide an additional parameter to be taken into consideration in evaluating the varying sensitivity of diabetic hearts to ischemia-reperfusion injury.

Title: Mean blood glucose and biological variation have greater influence on HbA1c levels than glucose instability: an analysis of data from the Diabetes Control and Complications Trial. Abstract: OBJECTIVE: Mean blood glucose (MBG) over 2-3 months is a strong predictor of HbA(1c) (A1C) levels. Glucose instability, the variability of blood glucose levels comprising the MBG, and biological variation in A1C (BV) have also been suggested as predictors of A1C independent of MBG. To assess the relative importance of MBG, BV, and glucose instability on A1C, we analyzed patient data from the Diabetes Control and Complications Trial (DCCT). RESEARCH DESIGN AND METHODS: A glucose profile set and sample for A1C were collected quarterly over the course of the DCCT from each participant (n = 1,441). The glucose profile set consisted of seven samples, one each drawn before and 90 min after breakfast, lunch, and dinner and one before bedtime. MBG and glucose instability (SD of blood glucose [SDBG]) were calculated as the arithmetic mean and SD of glucose profile set samples for each visit, respectively. A statistical model was developed to predict A1C from MBG, SDBG, and BV, adjusted for diabetes duration, sex, treatment group, stratum, and race. RESULTS: Data from 32,977 visits were available. The overall model was highly statistically significant (log likelihood = -41,818.75, likelihood ratio chi2[7] = 7,218.71, P > chi2 = 0.0000). MBG and BV had large influences on A1C based on their standardized coefficients. SDBG had only 1/14 of the impact of MBG and 1/10 of the impact of BV. CONCLUSIONS: MBG and BV have a large influence on A1C, whereas SDBG is relatively unimportant. Consideration of BV as well as MBG in the interpretation of A1C may enhance our ability to monitor diabetes management and predict complications.

Title: Regulation of very-low-density-lipoprotein lipid secretion in hepatocyte cultures derived from diabetic animals. Abstract: Hepatocytes were derived from 2-3-day streptozotocin-diabetic rats and maintained in culture for up to 3 days. Compared with similar cultures from normal animals, these hepatocytes secreted less very-low-density-lipoprotein (VLDL) triacylglycerol, but the decrease in the secretion of VLDL non-esterified and esterified cholesterol was not so pronounced. This resulted in the secretion of relatively cholesterol-rich VLDL particles by the diabetic hepatocytes. Addition of insulin for a relatively short period (24 h) further decreased the low rates of VLDL triacylglycerol secretion from the diabetic hepatocytes. The secretion of VLDL esterified and non-esterified cholesterol also declined. These changes occurred irrespective of whether or not exogenous fatty acids were present in the culture medium. Little or no inhibitory effect of insulin was observed after longer-term (24-48 h) exposure to the hormone. Both dexamethasone and a mixture of lipogenic precursors (lactate plus pyruvate) stimulated VLDL triacylglycerol and cholesterol secretion, but not to the levels observed in hepatocytes from normal animals. The low rate of hepatic VLDL secretion in diabetes contrasts with the increase in whole-body VLDL production rate. This suggests that the intestine is a major source of plasma VLDL in insulin-deficient diabetes.

Title: Specific changes of somatostatin mRNA expression in the frontal cortex and hippocampus of diabetic rats. Abstract: Abstract Most current studies of diabetic encephalopathy have focused on brain blood flow and metabolism, but there has been little research on the influence of diabetes on brain tissue and the causes of chronic diabetic encephalopathy. The technique of molecular biology makes it possible to explore the mechanism of chronic diabetic encephalopathy by testing the distribution of somatostatin in the brain. We have therefore analysed, by in situ hybridization histochemistry, the changes in somatostatin (SST) mRNA in the frontal cortex and hippocampus of rats made diabetic by the injection of streptozotocin. Ten Sprague-Dawley control rats were compared with ten streptozotocin-induced diabetic rats. The weight, blood glucose and urine glucose did not differ between the two groups before the injection of streptozotocin. Four weeks after the injection of streptozotocin the weight, blood glucose and urine glucose of the diabetic rats were, respectively, 199.1 +/- 15.6 g, 23.7 +/- 3.25 mmol L(-1) and (++) to (+++) whereas those of the control group were 265.5 +/- 30.3 g, 4.84 +/- 0.63 mmol L(-1) and (-). Somatostatin mRNA was reduced in the diabetic rats. The number of SST mRNA-positive neurons and the optical density of positive cells in the hippocampus and frontal cortex of the diabetic rats were 80.6 +/- 17.5 mm(-2) and 76.5 +/- 17.6 compared with 150.5 +/- 21.1 mm(-2) and 115.1 +/- 18.5 in the control rats. The induction of diabetes is thus associated with a decreased expression of SST mRNA in the hippocampus and frontal cortex, which might be an important component of chronic diabetic encephalopathy.

Title: Glycemic response to newly initiated diabetes therapies. Abstract: OBJECTIVE: The glycemic response to antihyperglycemic therapies for type 2 diabetes has been thoroughly evaluated in randomized controlled trials, but inadequately studied in real-world settings. STUDY DESIGN: We studied glycemic response among 15 126 type 2 diabetic patients who initiated any single new antihyperglycemic agent (metformin, sulfonylureas, thiazolidinediones, or insulin added to medical nutrition therapy or to existing diabetes therapies) during 1999-2000 within Kaiser Permanente of Northern California, an integrated healthcare delivery system. METHODS: Pre-post (3-12 months after initiation) change in glycosylated hemoglobin (A1C) was analyzed using ANCOVA (analysis of covariance) models adjusted for baseline A1C, concurrent (ongoing) antihyperglycemic therapy, demographics, health behaviors, medication adherence, clinical factors, and processes of care. RESULTS: Mean A1C was 9.01% (95% confidence interval [CI] 8.98%-9.04%) before therapy initiation and 7.87% (95% CI 7.85%-7.90%) 3 to 12 months after initiation (mean A1C reduction 1.14 percentage points; 95% CI 1.11-1.17). Overall, 30.2% (95% CI 29.2%-31.1%) of patients achieved glycemic target (A1C < 7%). Although baseline disease severity and concurrent therapies differed greatly across therapeutic classes, after adjustment for these baseline clinical characteristics, no significant differences were noted in glucose-lowering effect across therapeutic classes. Treatment effects did not differ by age, race, diabetes duration, obesity, or level of renal function. CONCLUSIONS: Metformin, sulfonylures, thiazolidinediones, and insulin were equally effective in improving glucose control. Nonetheless, most patients failed to achieve the glycemic target. Findings suggest that, to keep up with progressive worsening of glycemic control, patients and providers must commit to earlier, more aggressive therapy intensification, triggered promptly after A1C exceeds the recommended glycemic target.

Title: The gastric bypass operation reduces the progression and mortality of non-insulin-dependent diabetes mellitus. Abstract: Of 232 morbidly obese patients with non-insulin-dependent diabetes mellitus referred to East Carolina University between March 5, 1979, and January 1, 1994, 154 had a Roux-en-Y gastric bypass operation and 78 did not undergo surgery because of personal preference or their insurance company"s refusal to pay for the procedure. The surgical and the nonoperative (control) groups were comparable in terms of age, weight, body mass index, sex, and percentage with hypertension. The two groups were compared retrospectively to determine differences in survival and the need for medical management of their diabetes. Mean length of follow-up was 9 years in the surgical group and 6.2 years in the control group. The mean glucose levels in the surgical group fell from 187 mg/dl preoperatively and remained less than 140 mg/dl for up to 10 years of follow-up. The percentage of control subjects being treated with oral hypoglycemics or insulin increased from 56.4% at initial contact to 87.5% at last contact (P = 0.0003), whereas the percentage of surgical patients requiring medical management fell from 31.8% preoperatively to 8.6% at last contact (P = 0.0001). The mortality rate in the control group was 28% compared to 9% in the surgical group (including perioperative deaths). For every year of follow-up, patients in the control group had a 4.5% chance of dying vs. a 1.0% chance for those in the surgical group. The improvement in the mortality rate in the surgical group was primarily due to a decrease in the number of cardiovascular deaths.

Title: Exenatide versus insulin glargine in patients with suboptimally controlled type 2 diabetes: a randomized trial. Abstract: BACKGROUND: Physicians may use either insulin or exenatide injections for patients with type 2 diabetes mellitus who have poor glycemic control despite taking oral blood glucose-lowering drugs. OBJECTIVE: To compare effects of exenatide and insulin glargine on glycemic control in patients with type 2 diabetes mellitus that is suboptimally controlled with metformin and a sulfonylurea. DESIGN: 26-week multicenter, open-label, randomized, controlled trial. SETTING: 82 outpatient study centers in 13 countries. PATIENTS: 551 patients with type 2 diabetes and inadequate glycemic control (defined as hemoglobin A1c level ranging from 7.0% to 10.0%) despite combination metformin and sulfonylurea therapy. INTERVENTION: Exenatide, 10 microg twice daily, or insulin glargine, 1 daily dose titrated to maintain fasting blood glucose levels of less than 5.6 mmol/L (<100 mg/dL). MEASUREMENTS: Hemoglobin A1c level, fasting plasma glucose level, body weight, 7-point self-monitored blood glucose, standardized test-meal challenge, safety, and tolerability. RESULTS: Baseline mean hemoglobin A1c level was 8.2% for patients receiving exenatide and 8.3% for those receiving insulin glargine. At week 26, both exenatide and insulin glargine reduced hemoglobin A1c levels by 1.11% (difference, 0.017 percentage point [95% CI, -0.123 to 0.157 percentage point]). Exenatide reduced postprandial glucose excursions more than insulin glargine, while insulin glargine reduced fasting glucose concentrations more than exenatide. Body weight decreased 2.3 kg with exenatide and increased 1.8 kg with insulin glargine (difference, -4.1 kg [CI, -4.6 to -3.5 kg]). Rates of symptomatic hypoglycemia were similar, but nocturnal hypoglycemia occurred less frequently with exenatide (0.9 event/patient-year versus 2.4 events/patient-year; difference, -1.6 events/patient-year [CI, -2.3 to -0.9 event/patient year]). Gastrointestinal symptoms were more common in the exenatide group than in the insulin glargine group, including nausea (57.1% vs. 8.6%), vomiting (17.4% vs. 3.7%) and diarrhea (8.5% vs. 3.0%). LIMITATIONS: The trial was open-label and did not assess clinical complications related to diabetes. Of the 551 participants, 19.4% of those receiving exenatide and 9.7% of those receiving insulin glargine withdrew from the study. Only 21.6% of the insulin glargine group and 8.6% of the exenatide group achieved the target level for fasting plasma glucose of less than 5.6 mmol/L (<100 mg/dL). CONCLUSIONS: Exenatide and insulin glargine achieved similar improvements in overall glycemic control in patients with type 2 diabetes that was suboptimally controlled with oral combination therapy. Exenatide was associated with weight reduction and had a higher incidence of gastrointestinal adverse effects than insulin glargine.

Title: Assessing daily management in childhood diabetes. Abstract: One hundred sixty-eight patients with childhood diabetes (6 to 19 years of age) and their parents participated in 24-hr recall interviews concerning daily diabetes management behavior. Each patient and parent was interviewed independently on three separate occasions. The information obtained was used to construct measures of 13 different adherence behaviors. Parent-patient agreement was good to excellent for most of the 13 behaviors. Agreement was influenced by the patient's age, with the most consistently high parent-child agreement found in the 10- to 15-year-old age group. Factor analysis of the 13 adherence behaviors resulted in a five-factor solution accounting for 70.6% of the variance. Adherence in childhood diabetes appears to be a complex construct, consisting of at least five different components unrelated to each other. Teenagers in this sample were less adherent than their younger counterparts on most of the adherence measures studied.

Title: Effects of 15-month aldose reductase inhibition with fidarestat on the experimental diabetic neuropathy in rats. Abstract: We examined the effects of long-term treatment with an aldose reductase inhibitor (ARI) fidarestat on functional, morphological and metabolic changes in the peripheral nerve of 15-month diabetic rats induced by streptozotocin (STZ). Slowed F-wave, motor nerve and sensory nerve conduction velocities were corrected dose-dependently in fidarestat-treated diabetic rats. Morphometric analysis of myelinated fibers demonstrated that frequencies of abnormal fibers such as paranodal demyelination and axonal degeneration were reduced to the extent of normal levels by fidarestat-treatment. Axonal atrophy, distorted axon circularity and reduction of myelin sheath thickness were also inhibited. These effects were associated with normalization of increased levels of sorbitol and fructose and decreased level of myo-inositol in the peripheral nerve by fidarestat. Thus, the results demonstrated that long-term treatment with fidarestat substantially inhibited the functional and structural progression of diabetic neuropathy with inhibition of increased polyol pathway flux in diabetic rats.

Title: A comparative study of reaction times between type II diabetics and non-diabetics. Abstract: BACKGROUND: Aging has been shown to slow reflexes and increase reaction time to varied stimuli. However, the effect of Type II diabetes on these same reaction times has not been reported. Diabetes affects peripheral nerves in the somatosensory and auditory system, slows psychomotor responses, and has cognitive effects on those individuals without proper metabolic control, all of which may affect reaction times. The additional slowing of reaction times may affect every-day tasks such as balance, increasing the probability of a slip or fall. METHODS: Reaction times to a plantar touch, a pure tone auditory stimulus, and rightward whole-body lateral movement of 4 mm at 100 mm/s2 on a platform upon which a subject stood, were measured in 37 adults over 50 yrs old. Thirteen (mean age = 60.6 +/- 6.5 years) had a clinical diagnosis of type II diabetes and 24 (mean age = 59.4 +/- 8.0 years) did not. Group averages were compared to averages obtained from nine healthy younger adult group (mean age = 22.7 +/- 1.2 years). RESULTS: Average reaction times for plantar touch were significantly longer in diabetic adults than the other two groups, while auditory reaction times were not significantly different among groups. Whole body reaction times were significantly different among all three groups with diabetic adults having the longest reaction times, followed by age-matched adults, and then younger adults. CONCLUSION: Whole body reaction time has been shown to be a sensitive indicator of differences between young adults, healthy mature adults, and mature diabetic adults. Additionally, the increased reaction time seen in this modality for subjects with diabetes may be one cause of increased slips and falls in this group.

Title: Microarray analysis reveals novel gene expression changes associated with erectile dysfunction in diabetic rats. Abstract: To investigate the full range of molecular changes associated with erectile dysfunction (ED) in Type 1 diabetes, we examined alterations in penile gene expression in streptozotocin-induced diabetic rats and littermate controls. With the use of Affymetrix GeneChip arrays and statistical filtering, 529 genes/transcripts were considered to be differentially expressed in the diabetic rat cavernosum compared with control. Gene Ontology (GO) classification indicated that there was a decrease in numerous extracellular matrix genes (e.g., collagen and elastin related) and an increase in oxidative stress-associated genes in the diabetic rat cavernosum. In addition, PubMatrix literature mining identified differentially expressed genes previously shown to mediate vascular dysfunction [e.g., ceruloplasmin (Cp), lipoprotein lipase, and Cd36] as well as genes involved in the modulation of the smooth muscle phenotype (e.g., Kruppel-like factor 5 and chemokine C-X3-C motif ligand 1). Real-time PCR was used to confirm changes in expression for 23 relevant genes. Further validation of Cp expression in the diabetic rat cavernosum demonstrated increased mRNA levels of the secreted and anchored splice variants of Cp. CP protein levels showed a 1.9-fold increase in tissues from diabetic rats versus controls. Immunohistochemistry demonstrated localization of CP protein in cavernosal sinusoids of control and diabetic animals, including endothelial and smooth muscle layers. Overall, this study broadens the scope of candidate genes and pathways that may be relevant to the pathophysiology of diabetes-induced ED as well as highlights the potential complexity of this disorder.

Title: Plasma lactate concentration in obesity and type 2 diabetes. Abstract: The purpose of this study was three-fold: 1) to define the effects of obesity and Type 2 diabetes on plasma lactate concentrations; 2) to relate changes in plasma lactate concentration to plasma glucose and insulin concentrations; and 3) to evaluate the effect of differences in blood sample processing on plasma lactate determination in a disparate population group. To accomplish this, fasting plasma lactate concentrations were determined in 30 volunteers (10 non-obese individuals with normal glucose tolerance, 10 obese individuals with Type 2 diabetes) on blood drawn, processed, and maintained in a variety of ways. Results demonstrated that fasting plasma lactate measurements were least confounded when blood was drawn without the subject "hand pumping" following venous occlusion, the samples maintained on ice at 4 degrees C until precipitated with perchloric acid, and kept as this temperature until lactate concentration was determined. Under these conditions, plasma lactate concentration was lowest in the non-obese group with normal glucose tolerance (0.81 +/- 0.07 mmol/L), highest in the obese subjects with Type 2 diabetes (1.46 +/- 0.14 mmol/L), and intermediate in obese individuals with normal glucose tolerance (1.17 +/- 0.13 mmol/L). All three groups were significantly different from each other. In addition plasma lactate concentrations were associated with both fasting plasma glucose and glycated haemoglobin concentrations.

Title: Five weeks of treatment with the GLP-1 analogue liraglutide improves glycaemic control and lowers body weight in subjects with type 2 diabetes. Abstract: AIMS: Effects of the long acting GLP-1 analogue--liraglutide in subjects with type 2 diabetes. METHODS: 144 type 2 diabetic subjects on metformin treatment (1000 mg BID) were randomised to 5 weeks of treatment (double-blind) with metformin plus liraglutide, liraglutide or metformin, or metformin plus glimepiride (open label). The dose of liraglutide was increased weekly from 0.5 to 2 mg OD. RESULTS: Liraglutide added to metformin monotherapy was associated with a significant reduction in fasting serum glucose (FSG) (-3.9 mM -4.9; -2.9) (primary objective), and HbA1c levels (-0.8% -1.2; -0.4). Furthermore, liraglutide in combination with metformin vs. metformin plus glimepiride significantly reduced FSG (-1.2 mM -2.2; -0.2). In addition, body weight was significantly lower in the metformin plus liraglutide vs. the metformin plus glimepiride group (-2.9 kg -3.6; -2.1). There were no biochemically confirmed episodes of hypoglycaemia with liraglutide treatment. Nausea was the most frequently reported adverse event following liraglutide therapy, it was transient in nature, and led to withdrawal of only 4% of the subjects. CONCLUSIONS: Using a weekly dose-titration liraglutide is well tolerated up to 2 mg daily. While liraglutide caused transient gastrointestinal side effects, this rarely interfered with continuing treatment. An improvement in FSG over that in control groups was seen for liraglutide as an add-on to metformin. In the latter case, body weight was reduced in comparison to metformin plus glimepiride. Liraglutide is a promising drug for the treatment of type 2 diabetes.

Title: The perception of safe driving ability during hypoglycemia in patients with type 1 diabetes mellitus. Abstract: PURPOSE: Insulin-induced hypoglycemia and its sequelae of cognitive impairment may place patients with type 1 diabetes at risk when driving and when making decisions about driving. Little is known about the factors that influence judgments of safe driving ability during hypoglycemia in these patients. PATIENTS AND METHODS: Thirty men and 30 women with uncomplicated type 1 diabetes (age [mean +/- SD] 33 +/- 9 years, duration 9 +/- 3 years, hemoglobin A1c level 8.7% +/- 1.0%) underwent a stepped hypoglycemic insulin clamp. Serum glucose levels were reduced from 120 mg/dL to 80, 70, 60, 50, and then 40 mg/dL during 190 minutes. At each glucose plateau, patients completed a symptom questionnaire and neuropsychological test, estimated their glucose level, and reported whether they could drive safely. RESULTS: The proportion of patients judging that they could drive safely decreased as serum glucose levels decreased from 70% at 120 mg/dL to 22% at 40 mg/dL. Men and middle-aged patients were more likely to consider it safe to drive during hypoglycemia than women and those under 25 years of age. Those who were symptomatic and those who recognized hypoglycemia were less likely to report safe driving ability during hypoglycemia. Most patients who were cognitively impaired appeared to recognize this and reported that they could not drive safely at a serum glucose level of 40 mg/dL. CONCLUSIONS: Adults with type 1 diabetes need educational reinforcement of safe driving habits, particularly to check glucose levels before driving. Glucose levels less than 70 mg/dL should be treated before driving. This information is as important for middle-aged, experienced drivers as it is for younger, inexperienced drivers.

Title: The effect of diabetes mellitus on sterol synthesis in the intact rat. Abstract: Diabetes mellitus in both humans and animals is characterized by elevations in plasma cholesterol concentrations. The cause of this hypercholesterolemia is unknown. The present study employed tritiated water to quantity sterol synthesis in intact diabetic and control animals. Sterologenesis was 60-246% greater in the gut of diabetic animals than in controls. This enhancement of sterol synthesis occurred soon after the onset of diabetes and persisted for at least 3 wk. Moreover, insulin therapy markedly decreased gut sterol synthesis in diabetic animals to levels only slightly greater than in controls. Diabetes increased sterol synthesis primarily in the small intestine, but a small increase was also observed in the large intestine. Subfractionation of the small intestine into epithelial cell and muscularis cell layers revealed an increased sterologenesis in both layers. Quantitatively, though, the epithelial layer accounted for the majority of the enhancement of small intestine sterol synthesis observed in diabetic animals. De novo sterologenesis in tissues other than the intestines (liver, skin, stomach, or remaining carcass) was not significantly altered by diabetes. This study demonstrates that diabetes markedly stimulates sterol synthesis, an effect that is specifically localized to the intestines.

Title: Aminoacid polymorphisms of insulin receptor substrate-1 in non-insulin-dependent diabetes mellitus. Abstract: Since relative or absolute insulin deficiency and insulin insensitivity are involved in the aetiology of non-insulin-dependent diabetes mellitus (NIDDM), we examined whether patients with NIDDM exhibit genetic variability in the coding region of insulin receptor substrate-1 (IRS-1), a candidate gene that is ubiquitous in insulin-sensitive and insulin-like growth factor 1 (IGF1) sensitive tissues, including those that determine glucose production and clearance and those with regulatory effects on pancreatic beta-cell function. IRS-1 has a central role as an adaptor molecule that links the insulin-receptor and IGF1-receptor kinases with enzymes that regulate cellular metabolism and growth. Single-stranded conformation polymorphism analysis and direct nucleotide sequencing were applied to genomic DNA from 86 unrelated patients with NIDDM and 76 normoglycaemic controls. 10 of the patients with NIDDM and 3 of the controls were heterozygous at codon 972 for a polymorphism in which glycine was substituted with arginine. Moreover, at codon 513, 6 patients with NIDDM and 2 controls had a heterozygous polymorphism with a transition from alanine to proline. None of the polymorphism carriers had both aminoacid variants and the total allelic frequency of IRS-1 polymorphisms was about three times higher in patients with NIDDM than in controls (p = 0.02). Both aminoacid substitutions were located close to tyrosine phosphorylation motifs that are putative recognition sites for insulin and IGF1 signal transmission proteins. Analysis of the phenotypes showed that patients with NIDDM who had IRS-1 variants did not differ in their degree of insulin resistance compared with patients without known IRS-1 polymorphisms. However, carriers of the codon 972 variant had significantly lower plasma levels of fasting insulin and C-peptide. Our results suggest that aminoacid polymorphisms in IRS-1 may be involved in the aetiology of a subset of late-onset NIDDM.

Title: Metabolic and vascular determinants of impaired cognitive performance and abnormalities on brain magnetic resonance imaging in patients with type 2 diabetes. Abstract: AIMS/HYPOTHESIS: The determinants of cerebral complications of type 2 diabetes are unclear. The present study aimed to identify metabolic and vascular factors that are associated with impaired cognitive performance and abnormalities on brain MRI in patients with type 2 diabetes. METHODS: The study included 122 patients and 56 controls. Neuropsychological test scores were divided into five cognitive domains and expressed as standardised z values. Brain MRI scans were rated for white matter lesions (WML), cortical and subcortical atrophy, and infarcts. Data on glucose metabolism, vascular risk factors and micro- and macrovascular disease were collected. RESULTS: Patients with type 2 diabetes had more cortical (p < 0.001) and subcortical (p < 0.01) atrophy and deep WML (p = 0.02) than the control group and their cognitive performance was worse. In multivariate regression analyses within the type 2 diabetes group, hypertension (p < 0.05) and a history of vascular events (p < 0.01) were associated with worse cognitive performance, while statin use was associated (p < 0.05) with better performance. Retinopathy and brain infarcts on MRI were associated with more severe cortical atrophy (both p < 0.01) and statin use with less atrophy (p < 0.05). Insulin level and brain infarcts were associated with more severe WML and statin use with less severe WML (all p < 0.05). CONCLUSIONS/INTERPRETATION: Type 2 diabetes is associated with modest impairments in cognition, as well as atrophy and vascular lesions on MRI. This 'diabetic encephalopathy' is a multifactorial condition, for which atherosclerotic (macroangiopathic) vascular disease is an important determinant. Chronic hyperglycaemia, hyperinsulinaemia and hypertension may play additional roles.

Title: Comparison of the effects of pioglitazone and metformin on hepatic and extra-hepatic insulin action in people with type 2 diabetes. Abstract: OBJECTIVE: To determine mechanisms by which pioglitazone and metformin effect hepatic and extra-hepatic insulin action. RESEARCH DESIGN AND METHODS: Thirty-one subjects with type 2 diabetes were randomly assigned to pioglitazone (45 mg) or metformin (2,000 mg) for 4 months. RESULTS: Glucose was clamped before and after therapy at approximately 5 mmol/l, insulin raised to approximately 180 pmol/l, C-peptide suppressed with somatostatin, glucagon replaced at approximately 75 pg/ml, and glycerol maintained at approximately 200 mmol/l to ensure comparable and equal portal concentrations on all occasions. Insulin-induced stimulation of glucose disappearance did not differ before and after treatment with either pioglitazone (23 +/- 3 vs. 24 +/- 2 micromol x kg(-1) x min(-1)) or metformin (22 +/- 2 vs. 24 +/- 3 micromol x kg(-1) x min(-1)). In contrast, pioglitazone enhanced (P < 0.01) insulin-induced suppression of both glucose production (6.0 +/- 1.0 vs. 0.2 +/- 1.6 micromol x kg(-1) x min(-1)) and gluconeogenesis (n = 11; 4.5 +/- 0.9 vs. 0.8 +/- 1.2 micromol x kg(-1) x min(-1)). Metformin did not alter either suppression of glucose production (5.8 +/- 1.0 vs. 5.0 +/- 0.8 micromol x kg(-1) x min(-1)) or gluconeogenesis (n = 9; 3.7 +/- 0.8 vs. 2.6 +/- 0.7 micromol x kg(-1) x min(-1)). Insulin-induced suppression of free fatty acids was greater (P < 0.05) after treatment with pioglitazone (0.14 +/- 0.03 vs. 0.06 +/- 0.01 mmol/l) but unchanged with metformin (0.12 +/- 0.03 vs. 0.15 +/- 0.07 mmol/l). CONCLUSIONS: Thus, relative to metformin, pioglitazone improves hepatic insulin action in people with type 2 diabetes, partly by enhancing insulin-induced suppression of gluconeogenesis. On the other hand, both drugs have comparable effects on insulin-induced stimulation of glucose uptake.

Title: Insulin resistance in type 1 diabetes. Abstract: Insulin resistance plays a larger role in the type 1 diabetes disease process than is commonly recognized. The onset of type 1 diabetes is often heralded by an antecedent illness and/or the onset of puberty, both conditions associated with insulin resistance. In the face of a damaged beta-cell and thus reduced insulin secretion, this change is enough to manifest hyperglycemia. During the first year of clinical disease, considerable evidence suggests that the occurrence of clinical remission or 'honeymoon period' is due to a temporary resolution of the insulin-resistant state present at diagnosis. Intensive diabetes management is associated with both improved insulin sensitivity and beta-cell function. This indicates that the historical data on the changes in insulin secretion post-diagnosis may be inappropriate when designing current studies. The known physiological relationship between beta-cell function and insulin sensitivity complicates interpretation of insulin secretion data obtained as part of prevention or intervention trials. While it is recommended that at least a subset of subjects participating in these trials undergo formal measurements of insulin sensitivity to evaluate effects of therapy on this parameter independent of effects on the beta-cell, the sample size must be sufficient to determine an effect if present. Finally, one could speculate that it is possible that subsets of people with mild manifestations of the type 1 autoimmune disease process could benefit from treatments aimed at improving the insulin-resistant state.

Title: SNP43 of CAPN10 and the risk of type 2 Diabetes in African-Americans: the Atherosclerosis Risk in Communities Study. Abstract: Recently, an A-to-G variant in intron 3 (SNP43) of the calcium-activated neutral protease 10 gene (CAPN10) was identified as a possible type 2 diabetes susceptibility gene through positional cloning in Mexican-Americans. We conducted cross-sectional and prospective studies to evaluate the relation between SNP43 and type 2 diabetes and related traits in middle-aged African-American participants of the Atherosclerosis Risk in Communities Study, a population-based longitudinal study. At baseline, 269 prevalent diabetes cases and 1,159 nondiabetic control subjects were studied. Those with the G/G genotype were more likely to have diabetes than those with the A/G or A/A genotype (odds ratio [OR] 1.41, 95% CI 1.00-1.99, P = 0.05). In the prospective study, 166 of the control subjects developed incident diabetes over 9 years of follow-up. The incidence of diabetes for individuals with the G/G genotype did not differ significantly from those with at least one copy of the A allele (23.3 vs. 19.5 per 1,000 person years, P = 0.29). Pooling prevalent and incident diabetic cases together, individuals with the G/G genotype were approximately 40% more likely to have diabetes than those without (OR 1.38, 95% CI 1.04-1.83, P = 0.03). Because of the high frequency of the G allele (0.88), approximately 25% of the susceptibility to type 2 diabetes in African-Americans may be attributed to the G/G genotype at SNP43 of CAPN10, although most of the subjects with the G/G genotype did not develop diabetes over the 9 years of follow-up. We conclude from this large prospective study that the G allele of SNP43 of CAPN10 or another allele or gene that is in linkage disequilibrium with it increases susceptibility to type 2 diabetes in African-Americans.

Title: Islet amyloid and type 2 diabetes: from molecular misfolding to islet pathophysiology. Abstract: Islet amyloid polypeptide (IAPP, amylin) is secreted from pancreatic islet beta-cells and converted to amyloid deposits in type 2 diabetes. Conversion from soluble monomer, IAPP 1-37, to beta-sheet fibrils involves changes in the molecular conformation, cellular biochemistry and diabetes-related factors. In addition to the recognised amyloidogenic region, human IAPP (hIAPP) 20-29, the peptides human or rat IAPP 30-37 and 8-20, assume beta-conformation and form fibrils. These three amyloidogenic regions of hIAPP can be modelled as a folding intermediate with an intramolecular beta-sheet. A hypothesis is proposed for co-secretion of proIAPP with proinsulin in diabetes and formation of a 'nidus' adjacent to islet capillaries for subsequent accumulation of secreted IAPP to form the deposit. Although intracellular fibrils have been identified in experimental systems, extracellular deposition predominates in animal models and man. Extensive fibril accumulations replace islet cells. The molecular species of IAPP that is cytotoxic remains controversial. However, since fibrils form invaginations in cell membranes, small non-toxic IAPP fibrillar or amorphous accumulations could affect beta-cell stimulus-secretion coupling. The level of production of hIAPP is important but not a primary factor in islet amyloidosis; there is little evidence for inappropriate IAPP hypersecretion in type 2 diabetes and amyloid formation is generated in transgenic mice overexpressing the gene for human IAPP only against a background of obesity. Animal models of islet amyloidosis suggest that diabetes is induced by the deposits whereas in man, fibril formation appears to result from diabetes-associated islet dysfunction. Islet secretory failure results from progressive amyloidosis which provides a target for new therapeutic interventions.

Title: Tetrodotoxin-resistant sodium channels of dorsal root ganglion neurons are readily activated in diabetic rats. Abstract: To clarify the mechanism of hyperalgesia in diabetic neuropathy, we investigated the effects of streptozocin-induced hyperglycemia on tetrodotoxin-resistant Na+ channel activity of dorsal root ganglion neurons. Experiments were performed on enzymatically isolated neurons of dorsal root ganglia dissected from streptozocin-induced diabetic and their age-matched control rats. Membrane currents were recorded using the whole-cell patch-clamp technique. Mean current density of tetrodotoxin-resistant Na+ channels was significantly larger in neurons prepared from diabetic rats than in control neurons. Tetrodotoxin-resistant Na+ channels were activated at more negative potentials in diabetic than in control neurons. Curves representing the steady-state inactivation and the peak Na+ conductance as a function of membrane potential shifted to the negative side. The changes in gating property of the Na+ channel were observed six weeks after the injection of streptozocin, and still after eight months, indicating that tetrodotoxin-resistant Na+ channel abnormality starts to develop early and persists during the whole period of diabetes. These results suggest that neurons participating in nociception are highly excitable in diabetic animals. The present results may provide an important clue to the elucidation of hyperalgesia in diabetes.

Title: Genetic analysis of type 1 diabetes using whole genome approaches. Abstract: Whole genome linkage analysis of type 1 diabetes using affected sib pair families and semi-automated genotyping and data capture procedures has shown how type 1 diabetes is inherited. A major proportion of clustering of the disease in families can be accounted for by sharing of alleles at susceptibility loci in the major histocompatibility complex on chromosome 6 (IDDM1) and at a minimum of 11 other loci on nine chromosomes. Primary etiological components of IDDM1, the HLA-DQB1 and -DRB1 class II immune response genes, and of IDDM2, the minisatellite repeat sequence in the 5' regulatory region of the insulin gene on chromosome 11p15, have been identified. Identification of the other loci will involve linkage disequilibrium mapping and sequencing of candidate genes in regions of linkage.

Title: Alcohol consumption and risk of type 2 diabetes among older women. Abstract: OBJECTIVE: This study aimed to investigate the relation between alcohol consumption and type 2 diabetes among older women. RESEARCH DESIGN AND METHODS: Between 1993 and 1997, 16,330 women aged 49-70 years and free from diabetes were enrolled in one of the Dutch Prospect-EPIC (European Prospective Study Into Cancer and Nutrition) cohorts and followed for 6.2 years (range 0.1-10.1). At enrollment, women filled in questionnaires and blood samples were collected. RESULTS: During follow-up, 760 cases of type 2 diabetes were documented. A linear inverse association (P = 0.007) between alcohol consumption and type 2 diabetes risk was observed, adjusting for potential confounders. Compared with abstainers, the hazard ratio for type 2 diabetes was 0.86 (95% CI 0.66-1.12) for women consuming 5-30 g alcohol per week, 0.66 (0.48-0.91) for 30-70 g per week, 0.91 (0.67-1.24) for 70-140 g per week, 0.64 (0.44-0.93) for 140-210 g per week, and 0.69 (0.47-1.02) for >210 g alcohol per week. Beverage type did not influence this association. Lifetime alcohol consumption was associated with type 2 diabetes in a U-shaped fashion. CONCLUSIONS: Our findings support the evidence of a decreased risk of type 2 diabetes with moderate alcohol consumption and expand this to a population of older women.

Title: Early worsening of diabetic retinopathy in the Diabetes Control and Complications Trial. Abstract: OBJECTIVES: To document the frequency, importance of, and risk factors for "early worsening" of diabetic retinopathy in the Diabetes Control and Complications Trial (DCCT). METHODS: The DCCT was a multicenter, randomized clinical trial comparing intensive vs conventional treatment in insulin-dependent diabetic patients who had no to moderate nonproliferative retinopathy. Retinopathy severity was assessed in 7-field stereoscopic fundus photographs taken at baseline and every 6 months. For this study, worsening was defined as progression of 3 steps or more on the Early Treatment Diabetic Retinopathy Study final scale, as the development of soft exudates and/or intraretinal microvascular abnormalities, as the development of clinically important retinopathy, or as any of the above, and was considered "early" if it occurred between baseline and 12-month follow-up visits. RESULTS: Early worsening was observed at the 6- and/or 12-month visit in 13.1% of 711 patients assigned to intensive treatment and in 7.6% of 728 patients assigned to conventional treatment (odds ratio, 2.06; P < .001); recovery had occurred at the 18-month visit in 51% and 55% of these groups, respectively (P = .39). The risk of 3-step or greater progression from the retinopathy level present 18 months after entry into the trial was greater in patients who previously had had early worsening than in those who had not. However, the large long-term risk reduction with intensive treatment was such that outcomes in intensively treated patients who had early worsening were similar to or more favorable than outcomes in conventionally treated patients who had not. The most important risk factors for early worsening were higher hemoglobin A1c level at screening and reduction of this level during the first 6 months after randomization. We found no evidence to suggest that more gradual reduction of glycemia might be associated with less risk of early worsening. Early worsening led to high-risk proliferative retinopathy in 2 patients and to clinically significant macular edema in 3; all responded well to treatment. CONCLUSIONS: In the DCCT, the long-term benefits of intensive insulin treatment greatly outweighed the risks of early worsening. Although no case of early worsening was associated with serious visual loss, our results are consistent with previous reports of sight-threatening worsening when intensive treatment is initiated in patients with long-standing poor glycemic control, particularly if retinopathy is at or past the moderate nonproliferative stage. Ophthalmologic monitoring before initiation of intensive treatment and at 3-month intervals for 6 to 12 months thereafter seems appropriate for such patients. In patients whose retinopathy is already approaching the high-risk stage, it may be prudent to delay the initiation of intensive treatment until photocoagulation can be completed, particularly if hemoglobin A1c is high.

Title: Evidence of an increased number of type IIb muscle fibers in insulin-resistant first-degree relatives of patients with NIDDM. Abstract: Insulin resistance is a common feature in first-degree relatives of NIDDM patients. To explore the mechanism(s) behind this condition in more detail, a percutaneous muscle biopsy (vastus lateralis) was performed in 25 first-degree relatives of NIDDM patients and 21 control subjects to examine muscle fiber composition and capillary density. Insulin-stimulated glucose disposal (Rd) was determined employing a hyperinsulinemic-(insulin infusion rate 0.6 mU x kg[-1] x min[-1]) euglycemic clamp. Rd (5.76 +/- 0.35 vs. 8.06 +/- 0.36 mg x kg lean body weight [LBW]-1 x min[-], P < 0.001) and estimated VO2max (49.3 +/- 2.8 vs. 57.2 +/- 3.5 mg x kg LBW[-1] x min[-1], 0.05 < P < 0.10) were decreased in the relatives. The number of type IIb fibers (29.5 +/- 2.5 vs. 21.0 +/- 2.8%, P < 0.05) was increased in the relatives, whereas no significant differences were found in other fiber types or capillary density between the groups. Correlations were observed between number of type I fibers (positive), number of type IIb fibers (negative), and capillary density (positive) versus Rd as well as estimated VO2max (P < 0.05). In a multiple linear regression analysis with Rd as a dependent variable, estimated VO2max, family history of NIDDM, and number of type IIb fibers (P < 0.001, r2 = 0.64) significantly determined the level of Rd, whereas capillary density did not. In conclusion, insulin-resistant first-degree relatives of NIDDM patients are characterized by an increased number of type IIb muscle fibers. Whether this finding reflects a reduced physical activity level and fitness in the relatives or is of primary genetic origin remains to be determined.

Title: The traditional plant treatment, Sambucus nigra (elder), exhibits insulin-like and insulin-releasing actions in vitro. Abstract: Sambucus nigra (elder) has been documented as a traditional treatment of diabetes. In the present study, an aqueous extract of elder (AEE, 1 g/L) significantly increased 2-deoxy-glucose transport, glucose oxidation and glycogenesis of mouse abdominal muscle in the absence of added insulin (2 x 2 factorial design). in acute 20-min tests, 0.25-1 g/L AEE evoked a stepwise stimulation of insulin secretion from clonal pancreatic beta-cells. The insulin releasing effect of AEE (0.5 g/L) was significantly potentiated by 16.7 mmol/L of glucose and significantly reduced by 0.5 mmol/L of diazoxide. AEE did not further enhance insulin secretion in cells stimulated by 10 mmol/L of L-alanine, 1 mmol/L of 3-isobutyl-1-methylxanthine or a depolarizing concentration of KCl (25 mmol/L). Prior exposure of clonal pancreatic beta-cells to AEE did not alter subsequent stimulation of insulin secretion induced by 10 mmol/L of L-alanine, thereby precluding a detrimental effect on cell viability. The insulinotropic action of AEE was partially dependent upon use of heat during extract preparation. Activity of AEE was heat-stable, acetone-insoluble and unaltered by prolonged exposure to acid/alkali (0.1 mol/L of HCl and NaOH). However, activity was significantly decreased 41% by dialysis to remove components with molecular mass <2000 Da. Sequential extraction with solvents revealed activity in both methanol and water fractions, indicating a cumulative effect of more than one extract constituent. Known constituents of elder, including lectin, rutin and the lipophilic triterpenoid (lupeol) and sterol (beta-sitosterol), did not stimulate insulin secretion. The results demonstrate the presence of insulin-releasing and insulin-like activity in the traditional antidiabetic plant, Sambucus nigra.

Title: The DIACOM study (effect of DosIng frequency of oral Antidiabetic agents on the COMpliance and biochemical control of type 2 diabetes). Abstract: AIM: Sulphonylureas are widely used in the management of type 2 diabetes. The effectiveness of treatment with oral antidiabetic drugs depends largely on patient compliance. The objective of the DIACOM (effect of DosIng frequency of oral Antidiabetic agents on the COMpliance and biochemical control of type 2 diabetes) study was to compare the compliance of patients treated with once-daily (od) or twice-daily (bid) sulphonylureas. METHODS: One hundred and five patients, previously treated with glibenclamide, were randomized to receive gliclazide in modified-release formulation (MR) once daily or glibenclamide twice daily for 16 weeks, using an electronic monitoring system (MEMS). RESULTS: A significant difference in compliance was observed between the two groups. The overall compliance was 93.5+/-14.0% in the once-daily gliclazide MR group and 87.2+/-21.1% in the twice-daily glibenclamide group (p<0.05), and the correct number of doses was taken on 86.3+/-15.4 and 66.9+/-29.0% of treatment days respectively (p<0.0001). The percentage of missed doses was 9.3+/-12.5% in the once-daily group and 17.5+/-18.0% in the twice-daily group (p<0.01). The percentage of doses taken in the correct time window and correct inter-dose interval was higher in the once-daily group, as was therapeutic coverage. Patients in the gliclazide MR group also achieved significantly better glycaemic control [fasting plasma glucose and glycated haemoglobin (HbA(1c))] than those treated with glibenclamide (p<0.0001). CONCLUSIONS: The study demonstrates that patient compliance with once-daily gliclazide MR is significantly better than with twice-daily glibenclamide. Consistently better efficacy was observed for short-term (fasting glucose) and long-term glycaemic control (HbA(1c)) in the once-daily group. These results demonstrate the possible therapeutic advantages of once-daily agents over twice-daily agents in the treatment of type 2 diabetes.

Title: Effect of diabetic ketosis on jejunal glutaminase. Abstract: The intestine is capable of shifting its major fuel source from glutamine in the fed animal to ketone bodies in the fasted animal. Glutaminase (EC 3.5.1.2), the entry enzyme of glutamine oxidation, was examined for its function as a determinant in the utilization of jejunal fuel during diabetes and fasting. Male Sprague-Dawley rats were made ketotic to varied degrees by either fasting or the induction of diabetes with graded doses of streptozotocin (SZ). Specific activity of glutaminase was decreased in the diabetic animals to 64% (p less than 0.05) of controls in the group receiving 110 mg/kg SZ and 82% of controls in the group receiving 65 mg/kg SZ and to 78% (p less than 0.05) of controls in the fasted animals. The activity of glutaminase in the small intestine was negatively correlated to the concentration of beta-hydroxybutyrate in the plasma (r = -0.97, p less than 0.025) and jejunum (r = -0.92, p less than 0.05) for the four groups of animals. Specific activity of glutaminase was decreased in all cell types isolated along the villus-crypt axis of the small intestine from diabetic and fasted rats compared with control rats. The quantity of glutaminase-protein was determined by a dot immunobinding assay using an antibody to purified glutaminase. The activity of glutaminase relative to immunoreactive glutaminase-protein was significantly decreased (p less than 0.05) to 53% of control values in the 110 mg/kg SZ group, 77% in the 65 mg/kg SZ group, and 70% in the fasted group. These data indicate that an inactivation of glutaminase-protein may play a role in the ability of the intestine to shift its fuel source from glutamine to ketone bodies during diabetes and fasting.

Title: Incidence of type 1 (insulin-dependent) diabetes mellitus in Catalonia, Spain. The Catalan Epidemiology Diabetes Study Group. Abstract: The incidence of Type 1 (insulin-dependent) diabetes mellitus was prospectively evaluated in Catalonia, Spain in patients up to 30 years of age during the period 1987-1990. The population at risk (0-29 years) consisted of 2,690,394 inhabitants (total population of Catalonia 5,978,638). All the cases were independently identified from four sources: endocrinologists, sales of blood glucose monitors and insulin pen injectors, diabetes societies and diabetic summer camps. The degree of ascertainment was 90.1%. The overall observed incidence rate was 10.7 per 100,000 per year, being 11.5 per 100,000 per year in the 0-14 age group. The incidence in males (12.0 per 100,000 per year) was higher than in females (9.3 per 100,000 per year), with a male/female ratio of 1.36/l. The sex differences were only present in cases over 14 years of age. Age specific incidence rates per 100,000 per year were 4.4 (confidence interval 95%: 3.2-5.7) in the age group 0-4, 9.9 (8.5-11.4) in 5-9, 17.5 (15.7-19.4) in 10-14, 11.4 (9.9-13.0) in 15-19, 11.3 (9.7-13.0) in 20-24 and 8.5 (7.2-9.9) in 25-29. There was a seasonal onset pattern, with the highest incidence in winter (December-February). We conclude that the incidence of Type 1 diabetes observed in Catalonia during the period 1987-1990 is higher than that recently reported in other Mediterranean countries. This study offers the first standardized data on Type 1 diabetes incidence in Catalonia, including cases up to 30 years, and contributes to the knowledge of the epidemiology of diabetes in South Europe.

Title: Uncoupling protein-2 polymorphisms in type 2 diabetes, obesity, and insulin secretion. Abstract: The onset of type 2 diabetes (T2DM) is preceded by obesity, insulin resistance, and impaired beta-cell function. Uncoupling protein-2 (UCP2) is a widely expressed inner mitochondrial membrane protein. Common polymorphisms of the UCP2 gene have been implicated in diabetes, in obesity, and with changes in UCP2 mRNA levels. We tested the hypothesis that common UCP2 variants influence T2DM susceptibility in four parallel studies of separate populations. We typed the -866 promoter (G/A) variant, a nonsynonymous (Ala55Val or A55V) single-nucleotide polymorphism in exon 4, and a 45-nt insertion in the 3'-untranslated (3'UTR) region. Study populations included a case-control population study, a family-based association study, and a metabolic study of individuals who had been characterized for insulin sensitivity and secretion. To evaluate UCP2 mRNA levels, we examined a fourth population of subjects, who had undergone subcutaneous fat biopsy. All three variants showed a trend to an association with T2DM (P = 0.05 to 0.07) in the population but not the family-based association study. The 3' insertion/deletion (3'UTR I/D) variant was associated with body mass index (BMI, P = 0.035) among nondiabetic family members. Haplotype combinations were significantly associated with BMI (P = 0.028), triglyceride levels (P = 0.026), and fasting insulin (P = 0.029); highest values for the three traits were observed in individuals with the heterozygous combination GVI/AVD. In the metabolic study, all three variants were associated with an index of beta-cell compensation for insulin sensitivity (disposition index), particularly in interaction with family membership (P < 0.000001). Individuals homozygous for the -866 A allele had decreased adipose mRNA levels relative to GG homozygous individuals (P = 0.009), but the 3'UTR I/D variant had no impact on mRNA levels. We confirm modest effects of UCP2 variants on BMI and T2DM and show significant effects on insulin secretion in interaction with family-specific factors. However, the associated allele and the effects on gene expression are opposite to those reported previously.

Title: Homozygous combination of calpain 10 gene haplotypes is associated with type 2 diabetes mellitus in a Polish population. Abstract: OBJECTIVE: The polymorphisms of two genes have recently been associated with complex forms of type 2 diabetes mellitus (T2DM): calpain 10 and peroxisome proliferator-activated receptor-gamma (PPARgamma). Calpain 10 is a member of a large family of intracellular proteases. It was shown in Mexican-Americans and other populations that variants of three single nucleotide polymorphisms (SNPs), -43, -19, and -63, of this ubiquitously expressed protein influence susceptibility to T2DM. However, substantial differences were shown between ethnic groups in at risk alleles and haplotypes as well as in their attributable risk. Thus, it is important to determine the role of calpain 10 in various populations. AIM: To examine the role of calpain 10 SNPs -43, -19, and -63 in genetic susceptibility to T2DM in a Polish population. METHODS: Overall, 377 individuals were examined: 229 T2DM patients and 148 control individuals. The groups were genotyped for calpain 10 SNP-43, SNP-19, and SNP-63. SNP-19 was examined by electrophoresis of the PCR product on agarose gel by size, while the restriction fragment length polymorphism (RFLP) method was used for the two other markers. Differences in allele, genotype, haplotype, and haplotype combination distribution between the groups were examined by chi(2) test. RESULTS: Distributions of alleles, genotypes, and haplotypes at three loci defined by examined SNPs were not significantly different between the groups. However, the homozygote combination of 121 haplotype was more prevalent in the T2DM group than in the controls (17.9% vs 10.1%, P=0.039). No difference was observed in the 112/121 haplotype distribution. This heterozygous haplotype combination was associated with increased risk of T2DM in several populations. CONCLUSION: The results of our study suggest the association of calpain 10 121/121 haplotype combination created by SNPs -43, -19, and -63 with T2DM in a Polish population. However, we were not able to confirm the previously described role of the heterozygous 112/121 haplotype combination in susceptibility to T2DM.

Title: Changes in the gastric enteric nervous system and muscle: a case report on two patients with diabetic gastroparesis. Abstract: BACKGROUND: The pathophysiological basis of diabetic gastroparesis is poorly understood, in large part due to the almost complete lack of data on neuropathological and molecular changes in the stomachs of patients. Experimental models indicate various lesions affecting the vagus, muscle, enteric neurons, interstitial cells of Cajal (ICC) or other cellular components. The aim of this study was to use modern analytical methods to determine morphological and molecular changes in the gastric wall in patients with diabetic gastroparesis. METHODS: Full thickness gastric biopsies were obtained laparoscopically from two gastroparetic patients undergoing surgical intervention and from disease-free areas of control subjects undergoing other forms of gastric surgery. Samples were processed for histological and immunohistochemical examination. RESULTS: Although both patients had severe refractory symptoms with malnutrition, requiring the placement of a gastric stimulator, one of them had no significant abnormalities as compared with controls. This patient had an abrupt onset of symptoms with a relatively short duration of diabetes that was well controlled. By contrast, the other patient had long standing brittle and poorly controlled diabetes with numerous episodes of diabetic ketoacidosis and frequent hypoglycemic episodes. Histological examination in this patient revealed increased fibrosis in the muscle layers as well as significantly fewer nerve fibers and myenteric neurons as assessed by PGP9.5 staining. Further, significant reduction was seen in staining for neuronal nitric oxide synthase, heme oxygenase-2, tyrosine hydroxylase as well as for c-KIT. CONCLUSION: We conclude that poor metabolic control is associated with significant pathological changes in the gastric wall that affect all major components including muscle, neurons and ICC. Severe symptoms can occur in the absence of these changes, however and may reflect vagal, central or hormonal influences. Gastroparesis is therefore likely to be a heterogeneous disorder. Careful molecular and pathological analysis may allow more precise phenotypic differentiation and shed insight into the underlying mechanisms as well as identify novel therapeutic targets.

Title: Advanced glycation end product interventions reduce diabetes-accelerated atherosclerosis. Abstract: Advanced glycation end product (AGE) formation may contribute to the progression of atherosclerosis, particularly in diabetes. The present study explored atherosclerosis in streptozotocin-induced diabetic apolipoprotein E-deficient (apoE-/-) mice that were randomized (n = 20) to receive for 20 weeks no treatment, the AGE cross-link breaker ALT-711, or the inhibitor of AGE formation aminoguanidine (AG). A sixfold increase in plaque area with diabetes was attenuated by 30% with ALT-711 and by 40% in AG-treated mice. Regional distribution of plaque demonstrated no reduction in plaque area or complexity within the aortic arch with treatment, in contrast to the thoracic and abdominal aortas, where significant attenuation was seen. Diabetes-associated accumulation of AGEs in aortas and plasma and decreases in skin collagen solubility were ameliorated by both treatments, in addition to reductions in the vascular receptor for AGE. Collagen-associated reductions in the AGEs carboxymethyllysine and carboxyethyllysine were identified with both treatments. Diabetes was also accompanied by aortic accumulation of total collagen, specifically collagens I, III, and IV, as well as increases in the profibrotic cytokines transforming growth factor-beta and connective tissue growth factor and in cellular alpha-smooth muscle actin. Attenuation of these changes was seen in both treated diabetic groups. ALT-711 and AG demonstrated the ability to reduce vascular AGE accumulation in addition to attenuating atherosclerosis in these diabetic mice.

Title: An open, randomized, parallel-group study to compare the efficacy and safety profile of inhaled human insulin (Exubera) with metformin as adjunctive therapy in patients with type 2 diabetes poorly controlled on a sulfonylurea. Abstract: OBJECTIVE: To compare the efficacy and safety profile of adding inhaled human insulin (INH; Exubera) or metformin to sulfonylurea monotherapy in patients with poorly controlled type 2 diabetes. RESEARCH DESIGN AND METHODS: We performed an open-label, parallel, 24-week, multicenter trial. At week -1, patients uncontrolled on sulfonylurea monotherapy were divided into two HbA(1c) (A1C) arms: > or =8 to < or =9.5% (moderately high) and >9.5 to < or =12% (very high). Patients were randomized to adjunctive premeal INH (n = 225) or metformin (n = 202). The primary efficacy end point was change in A1C from baseline. RESULTS: In the A1C >9.5% arm, INH demonstrated a significantly greater reduction in A1C than metformin. Mean adjusted changes from baseline were -2.17 and -1.79%, respectively; between-treatment difference was -0.38% (95% CI -0.63 to -0.14, P = 0.002). In the A1C < or =9.5% arm, mean adjusted A1C changes were -1.94 and -1.87%, respectively (-0.07% [-0.33 to 0.19], P = 0.610), consistent with the noninferiority criterion. Hypoglycemia (events/subject-month) was greater in the INH (0.33) than in the metformin (0.15) group (risk ratio 2.16 [95% CI 1.67-2.78]), but there were no associated discontinuations. Other adverse events, except increased cough in the INH group, were similar. At week 24, changes in pulmonary function parameters were small and comparable between groups. Insulin antibody binding increased more with INH but did not have any associated clinical manifestations. CONCLUSIONS: In patients with type 2 diabetes poorly controlled on a sulfonylurea (A1C >9.5%), the addition of premeal INH significantly improves glycemic control compared with adjunctive metformin and is well tolerated.

Title: Polygenic nature of spontaneous diabetes in the rat. Permissive MHC haplotype and presence of the lymphopenic trait of the BB rat are not sufficient to produce susceptibility. Abstract: We describe the phenotypic characteristics of animals in the fifth backcross-intercross generation of a breeding program in which the RT1 u haplotype and the phenotypic trait responsible for the T-lymphopenia of BB rats have been transferred to the ACI background. In this generation of animals, 24% were lymphopenic with decreased numbers of PBL expressing CD5, TCR alpha, and RT6. The PBL of the lymphopenic animals had a decreased mitogenic response to ConA. All of the nonlymphopenic animals were homozygous for RT6.2. Phenotypic analysis of intestinal IEL revealed that this was also the case for the lymphopenic animals. Moreover, IEL of the lymphopenic animals exhibited a pattern of staining (increased numbers of TCR alpha beta+CD4+CD8+ and decreased numbers of TCR alpha beta+CD4-CD8+) similar to that of BB DP animals. The ACI.1U(BB)-lymphopenic animals, although having two of the genetic traits associated with the expression of spontaneous diabetes mellitus, uniformly fail to develop diabetes. Breeding studies in which these animals were crossed with BB and hBB rats suggest that other genes are necessary for development of overt diabetes.

Title: Protofibrillar islet amyloid polypeptide permeabilizes synthetic vesicles by a pore-like mechanism that may be relevant to type II diabetes. Abstract: Islet amyloid polypeptide (IAPP) and insulin are copackaged and cosecreted by pancreatic islet beta-cells. Non-insulin-dependent (type II) diabetes mellitus (NIDDM) is characterized by dysfunction and depletion of these beta-cells and also, in more than 90% of patients, amyloid plaques containing fibrillar IAPP. An aggregated but not necessarily fibrillar form of IAPP is toxic in cell culture, suggesting that prefibrillar oligomeric (protofibrillar) IAPP may be pathogenic. We report here that IAPP generates oligomeric species in vitro that are consumed as beta-sheet-rich fibrils grow. Protofibrillar IAPP, like protofibrillar alpha-synuclein, which is implicated in Parkinson's disease pathogenesis, permeabilizes synthetic vesicles by a pore-like mechanism. The formation of the IAPP amyloid pore is temporally correlated to the formation of early IAPP oligomers and its disappearance to the appearance of amyloid fibrils. Neither pores nor oligomers were formed by the nonfibrillogenic rat IAPP variant. The IAPP amyloid pore may be critical to the pathogenic mechanism of NIDDM, as other amyloid pores may be to Alzheimer's disease and Parkinson's disease.

Title: Increase in remission rate in newly diagnosed type I diabetic subjects treated with azathioprine. Abstract: Azathioprine (2 mg/kg) was given, in addition to routine insulin treatment, to alternate patients presenting with recent-onset type I diabetes. Treated (N = 13) and untreated (N = 11) patients did not differ significantly at diagnosis with respect to age, duration of symptoms, body weight, blood glucose, hemoglobin A1c, or presence of ketosis. Eight patients were treated for 12 mo, three elected to stop treatment at 6 mo, and treatment was stopped in two because of side effects. Seven treated patients had a remission compared with one untreated patient. At 12 mo these seven patients were distinguished by significantly higher basal and glucagon-stimulated levels of C-peptide (1.98 +/- 0.52 and 3.88 +/- 0.34 micrograms/L, respectively) compared with the other six treated patients (0.93 +/- 0.52 and 1.32 +/- 0.85 microgram/L, respectively), and by the persistence of islet cell cytoplasmic antibodies. Remissions were not sustained in the 1-2 yr after treatment, although relapsed patients required less insulin for control. These results corroborate those from nonrandomized trials using cyclosporine and suggest that protracted treatment with nonspecific immunosuppressive drugs may be necessary to avert insulin dependence.

Title: Transgenic activation of the kallikrein-kinin system inhibits intramyocardial inflammation, endothelial dysfunction and oxidative stress in experimental diabetic cardiomyopathy. Abstract: The mechanisms contributing to diabetic cardiomyopathy, as well as the protective pathways of the kallikrein-kinin-system (KKS), are incompletely understood. In a kallikrein-overexpressing rat model of streptozotocin (STZ)-induced diabetic cardiomyopathy, we investigated the involvement of inflammatory pathways, endothelial dysfunction, and oxidative stress. Six weeks after STZ injection, impairment of left ventricular (LV) function parameters measured by a Millar-tip catheter (peak LV systolic pressure; dP/dtmax; dP/dtmin) was accompanied by a significant increment of ICAM-1 and VCAM-1 (CAMs) expression, as well as of beta2-leukocyte-integrins+ (CD18+, CD11a+, CD11b+) and cytokine (TNF-alpha and IL-1beta)-expressing infiltrates in male Sprague-Dawley (SD-STZ) rats compared with normoglycemic littermates. Furthermore, SD-STZ rats demonstrated a significant impairment of endothelium-dependent relaxation evoked by acetylcholine and significantly increased plasma TBARS (plasma thiobarbituric acid reactive substances) levels as a measure of oxidative stress. These diabetic cardiomyopathy-associated alterations were significantly attenuated (P<0.05) in diabetic transgenic rats expressing the human kallikrein 1 (hKLK1) gene with STZ-induced diabetes. CAMs expression, beta2-leukocyte-integrins+, and cytokine-expressing infiltrates correlated significantly with all evaluated LV function parameters. The multiple protective effects of the KKS in experimental diabetic cardiomyopathy comprise the inhibition of intramyocardial inflammation (CAMs expression, beta2-leukocyte-integrins+ infiltration and cytokine expression), an improvement of endothelium-dependent relaxation and the attenuation of oxidative stress. These insights might have therapeutic implications also for human diabetic cardiomyopathy.

Title: High frequency of unrecognized hypoglycaemias in patients with Type 2 diabetes is discovered by continuous glucose monitoring. Abstract: AIMS: To evaluate the use of a CGMS in the detection of hypoglycaemia in people with type 2 diabetes as an outpatient procedure. METHODS: 31 type 2 diabetic patients underwent glucose monitoring by means of CGMS (Medtronic MiniMed) for up to three days. Patients took part in at least four SMBG (self monitoring blood glucose) tests per day. After three days of monitoring, the CGMS data was downloaded and analysed by a physician to identify the frequency of hypoglycaemias (< or =50 mg/dl) and borderline values (51-70 mg/dl), their duration and distribution. Findings were discussed with the patient and if necessary treatment was adjusted. Eight weeks later, monitoring was repeated to asses the effects of the adjusted treatment. RESULTS: Average duration of sensor wear was 4.19 days. Correlation between the sensor and the SMBG readings was high. A high number of hypoglycaemias and borderline values were detected by the CGMS, most of them unrecognized by the patient. The frequency of hypoglycaemias and borderline values just as the duration could be significantly reduced from first to second monitoring. CONCLUSION: Using the CGMS in type 2 diabetic patients achieved the detection of numerous hypoglycaemias and borderline values both nocturnal and/or unnoticed. The CGMS provides accurate data, which cannot be achieved by conventional SMBG tests. That opens the possibility for treatment adjustment and improvement in metabolic control. For patients it provides a better understanding of the effects of insulin or oral agents, nutrition and exercises to their glucose level.

Title: Leptin and body fat in type 2 diabetes and monodrug therapy. Abstract: To better understand the relations among leptin, insulin, and body fat during the metabolic progression to diabetes and during drug monotherapy, metabolic parameters were examined in subjects classified as 1) type 2 diabetes; 2) impaired fasting glucose or mild diabetes mellitus; 3) nondiabetic, matched for body mass index (BMI); and 4) nonobese, nondiabetic. Diabetic subjects were also studied during no pharmacological treatment, after 3 months of randomization to metformin or glyburide, and after 3 months of cross-over to the opposite drug. Log leptin correlated more with percent body fat (slope, 0.042; confidence interval, 0.036-0.047; r(2) = 0.826; P < 0.0001) than with total fat mass, percent truncal or nontruncal fat, or BMI. When normalized to percent fat, leptin did not differ by gender. Leptin normalized to percent fat was 35% less in untreated diabetes than that in BMI-matched controls (P < 0.001). Leptin normalized to percent fat was increased by 25% (P < 0.01) as a result of glyburide therapy compared with pretreatment values, but was unchanged by therapy with metformin. Across a spectrum of subjects with diabetes, impaired fasting glucose/mild diabetes, or BMI-matched nondiabetic controls, normalized leptin significantly correlated with glucose-induced insulin release, but not with insulin sensitivity. Our data suggest that plasma leptin is reduced in untreated type 2 diabetes probably as a consequence of reduced insulin secretion and that circulating leptin concentrations are differentially affected by monodrug therapy.

Title: Thyroid autoimmunity in children and adolescents with type 1 diabetes: a multicenter survey. Abstract: OBJECTIVE: To investigate thyroid autoimmunity in a very large nationwide cohort of children and adolescents with type 1 diabetes. RESEARCH DESIGN AND METHODS: Data were analyzed from 17,749 patients with type 1 diabetes aged 0.1-20 years who were treated in 118 pediatric diabetes centers in Germany and Austria. Antibodies to thyroglobulin (anti-TG) and thyroperoxidase (anti-TPO) were measured and documented at least once in 7,097 patients. A total of 49.5% of these patients were boys, the mean age was 12.4 years (range 0.3-20.0 years), and the mean duration of diabetes was 4.5 years (range 0.0-19.5 years). A titer exceeding 100 units/ml or 1:100 was considered significantly elevated. RESULTS: In 1,530 patients, thyroid antibody levels were elevated on at least one occasion, whereas 5,567 were antibody-negative during the observation period. Patients with thyroid antibodies were significantly older (P < 0.001), had a longer duration of diabetes (P < 0.001), and developed diabetes later in life (P < 0.001) than those without antibodies. A total of 63% of patients with positive antibodies were girls, compared with 45% of patients without antibodies (P < 0.001). The prevalence of significant thyroid antibody titers increased with increasing age; the highest prevalence was in the 15- to 20-year age group (anti-TPO: 16.9%, P < 0.001; anti-TG: 12.8%, P < 0.001). Thyroid-stimulating hormone (TSH) levels were higher in patients with thyroid autoimmunity (3.34 microU/ml, range 0.0-615.0 microU/ml) than in control subjects (1.84 microU/ml, range 0.0-149.0 microU/ml) (P < 0.001). Even higher TSH levels were observed in patients with both anti-TPO and anti-TG (4.55 microU/ml, range 0.0-197.0 microU/ml). CONCLUSIONS: Thyroid autoimmunity seems to be particularly common in girls with diabetes during the second decade of life and may be associated with elevated TSH levels, indicating subclinical hypothyroidism.

Title: Reducing acute adverse outcomes in youths with type 1 diabetes: a randomized, controlled trial. Abstract: OBJECTIVE: Both acute and chronic complications of diabetes account for a disproportionate percentage of US health care expenditures. Despite improvements in diabetes care, the incidence of adverse events in children with type 1 diabetes remains high, particularly for youths with poor glycemic control. Cost-effective intervention programs designed to reduce complications are needed. This study evaluated a low-intensity, nonmedical intervention using a case manager (called a "Care Ambassador"), with and without the supplementation of psychoeducational modules, designed to monitor and encourage routine diabetes care visits to reduce short-term adverse outcomes and improve glycemic control in youths with type 1 diabetes. METHODS: We performed a 2-year prospective, randomized clinical trial in 299 youths with type 1 diabetes, aged 7 to 16 years, comparing 3 treatment programs (Care Ambassador [CA], Care Ambassador plus psychoeducational modules [CA+], and standard multidisciplinary diabetes care [SC]). The study was conducted in a large metropolitan US city from April 1997 through April 2000. Number of medical visits, frequency of hypoglycemic events, hospital/emergency department (ED) utilization, and glycosylated hemoglobin A1c were assessed during follow-up. RESULTS: During the 2-year study period, both the CA and CA+ groups had significantly more routine visits (mean [standard deviation]: 7.3 [2.06] and 7.5 [2.02], respectively) compared with the SC group (5.4 [2.62]). The CA+ intervention group had significantly reduced rates of short-term adverse outcomes compared with the other 2 groups; 25% fewer total hypoglycemic events, 60% fewer severe hypoglycemic events, and 40% fewer hospitalizations and ED visits. "High-risk" youths in the CA+ group (baseline glycosylated hemoglobin A1c > or =8.7%) were 3.4-fold (1.57-7.41) more likely to improve their glycemic control compared with those at high risk in the other 2 groups. CONCLUSIONS: For youths with type 1 diabetes, the CA and CA+ interventions increased visit frequency. Youths in the CA+ intervention had reduced rates of hypoglycemia and hospital/ED utilization with estimated annual cost savings of 80 000 dollars to 90 000 dollars. The CA+ intervention compared with the other 2 groups improved glycemic control in "high-risk" youths. Nonmedical case management incorporating psychoeducational modules seems to be a cost-effective approach to improving outcomes in youths with diabetes.

Title: HLA-A, B, C and DR antigen associations in insulin dependent diabetes mellitus (IDDM) in South African Negro (black) and Cape coloured people. Abstract: HLA-A, B, C and DR antigen frequencies were determined in South African Negro (Black) (50) and Cape Coloured (57) patients with insulin dependent diabetes mellitus (IDDM) and in appropriate controls. The Black patients failed to show associations commonly reported for American Black patients with IDDM but did show a weakly significant increase in the DRw9 frequency. However, this antigen was rare even in the patient group and HLA associated genes do not appear to play a major role in the pathogenesis of IDDM in these people. The Cape Coloureds have a high proportion of Caucasoid genes. Coloured IDDM patients had the expected low DR2 and high DR4 frequencies. Unexpectedly the Cape Coloureds failed to show significant associations of IDDM with B8 or DR3.

Title: Diagnosis of pancreatic cancer. Alteration of glucose metabolism. Abstract: Alterations of glucose metabolism occur frequently in association with pancreatic cancer. Whether diabetes predisposes or is a consequence of pancreatic cancer has not been settled. We have found that induced diabetes prevents development of pancreatic cancer in the hamster model and that genetically diabetic Chinese hamsters resist pancreatic cancer induction, whereas the nondiabetic strain does not. Also, preliminary clinical data indicates that diabetes is associated with pancreatic cancer and that the two conditions develop simultaneously. We have found diabetes or impaired glucose tolerance in 76% of the pancreatic cancer patients at the time of cancer diagnosis. The diabetic condition improved after 75% pancreatectomy. Although the preliminary observations suggest that diabetes accompanies the disorder of pancreatic cancer, additional data are needed before any conclusion can be drawn.

Title: Aldosterone escape during blockade of the renin-angiotensin-aldosterone system in diabetic nephropathy is associated with enhanced decline in glomerular filtration rate. Abstract: AIMS/HYPOTHESIS: It has been suggested that aldosterone plays a role in the initiation and progression of renal disease independently of arterial blood pressure and plasma angiotensin II levels. We evaluated the influence of plasma aldosterone levels on progression of diabetic nephropathy during long-term blockade of the renin-angiotensin-aldosterone system. METHODS: A total of 63 hypertensive patients with type 1 diabetes and diabetic nephropathy were treated with losartan, 100 mg once daily, for a mean follow-up period of 35 months. Plasma aldosterone, GFR, albuminuria and 24-h blood pressure were determined at baseline and at regular intervals during the study. RESULTS: Patients were divided according to their increasing or decreasing levels of plasma aldosterone during long-term losartan treatment in an escape group (n=26) and a non-escape group (n=37). In the escape group, aldosterone levels increased from (geometric mean [95% CI]) 57 pg/ml (43-76 pg/ml) at 2 months, to 102 pg/ml (78-134 pg/ml) at the end of the study (p<0.01). The corresponding levels in the non-escape group were 83 pg/ml (69-102 pg/ml) and 49 pg/ml (40-60 pg/ml; p<0.01). The median rate of decline in GFR was 5.0 ml.min(-1).year(-1) (range 0.4-15.9 ml.min(-1).year(-1)) in the escape group, compared with 2.4 ml.min(-1).year(-1) (-1.6 to 11.0 ml.min(-1).year(-1)) in the non-escape group (p<0.005). The increase in plasma aldosterone correlated with the rate of decline in GFR (r(2)=0.19, p<0.001), corresponding to a decline in GFR of 1.5 ml.min(-1).year(-1) for every two-fold increase in plasma aldosterone. Pre-treatment and treatment values of plasma aldosterone were not related to albuminuria or to changes in albuminuria during the study. CONCLUSIONS/INTERPRETATION: Our data suggest that aldosterone escape during long-term blockade of the renin-angiotensin-aldosterone system is associated with an enhanced decline in GFR in patients with type 1 diabetes and diabetic nephropathy.

Title: The new type 2 diabetes gene TCF7L2. Abstract: PURPOSE OF REVIEW: Common variants in the gene that encodes the transcription factor 7-like 2 (TCF7L2) have been strongly associated with type 2 diabetes. This highly reproducible association may uncover novel mechanisms of glycemic pathophysiology. RECENT FINDINGS: The initial publication of an association of common variants in TCF7L2 with type 2 diabetes in people of European descent has been followed by an avalanche of replication reports. These papers not only confirm the original finding, but also extend it to other populations, fine map the source of the association signal, describe its effect on metabolic parameters in humans, open the door to a more precise molecular characterization, and provide an insight into its possible impact on diabetes therapy. SUMMARY: The discovery of TCF7L2 as a diabetes gene illustrates that novel true diabetes genes can be found, their association with type 2 diabetes replicated and their effect incorporated into risk prediction models. It is hoped that the detection of other such genes in genome-wide association scans will help elucidate the genetic architecture of this disease.

Title: Antibodies against ganglioside GT3 in the sera of patients with type I diabetes mellitus. Abstract: Clinical and experimental data support the concept that type I diabetes mellitus results from autoimmune destruction of pancreatic beta cells. Although both proteins and glycolipids are targets of anti-islet cell antibodies, the Ag have not been purified or characterized. Previously, we observed that rat insulinoma (RIN) cell lines varied in their reactivity with both human antibodies and murine mAb A2B5, which binds to polysialo gangliosides. To determine the chemical basis of the varied immunoreactivity, we analyzed the glycosphingolipids of 5 RIN lines. Glycolipids bound by two mAb and by antibodies in the sera of type I diabetics were identified. The more immunoreactive RIN lines contained a much higher content of gangliosides and a higher proportion of complex gangliosides. The major gangliosides were GM3, GD3, and GT3. By high performance TLC immunostaining, we demonstrated that A2B5 and R2D6, an anti-beta cell murine mAb, bound most strongly to ganglioside GT3. The binding of human sera to gangliosides was analyzed by an ELISA assay. Although both normal and diabetic sera contained antibodies to various glycolipids, binding to GT3 was significantly elevated in 31 new-onset type I diabetics (p less than 0.001). The presence of the GT3 trisialosyl epitope on human islet cells was shown by immunofluorescent staining by both R2D6 and A2B5. These findings support previous suggestions that gangliosides play an important role in the immunopathology of type I diabetes, and identify for the first time a specific ganglioside Ag that is the target for autoantibodies in a subset of diabetic patients.

Title: Diabetes mellitus is equally frequent in chronic HCV and HBV infection. Abstract: OBJECTIVE: To see the association of type 2 diabetes mellitus (Type 2 DM) in patients suffering from chronic HBV or HCV related liver disease. SETTING: Patients were selected from the gastroenterology OPD of the medical research centre, diabetic controls from private diabetes clinic and healthy controls from the blood bank of the hospital. METHODS: Patients with chronic liver disease had HBV, HCV tested using ELISA and blood sugar using a glucometer mostly as a 2 hour post prandial sample. Healthy controls had their sugar and ALT checked while donating blood and HBV, HCV were checked routinely. In diabetic controls, blood sample was taken as sera stored for HBV,HCV and ALT and later tested in batches. A random sugar of > or = 200 mg/dl was taken as diabetes. RESULTS: Of 400 patient with chronic liver disease 302 had HCV and 98 HBV infection. Diabetes was found in 24.5% HCV and 19.4% HBV related cases (not significant). Out of 410 healthy controls 18 were HCV and 17 HBV positive. Diabetes was found in only 1 (5.6%) HCV positive control and none of the HBV positive controls. Of 196 diabetics 10 (5.1%) were HCV positive and none HBV positive. Diabetes was more frequent in patients having liver cirrhosis than in those having chronic hepatitis (P < 0.01). CONCLUSION: Diabetes is equally frequent in both HBV and HCV related disease but is significantly more in those with chronic liver disease than in controls. The pancreatic damage secondary to extrahepatic viral replication appears to be the major cause but genetic factors also need to be explored.

Title: Eating disorders in patients with insulin-dependent diabetes mellitus. Abstract: The frequency of anorectic/bulimic disturbances in a sample of male and female subjects with insulin-dependent diabetes mellitus was compared to that of male and female normal controls. The results suggest an overrepresentation of anorexia/bulimia in the female diabetics. Prevalence of eating disorders was determined from the scores on the Eating Attitudes Test. As a group, the female diabetics had significantly (p less than .05) higher scores on the test, suggesting a greater "awareness" of topics related to food and eating. The results are discussed within a risk-factor model, in which insulin-dependent diabetes mellitus may be viewed as one factor in the development of eating disorders.

Title: Reductions in biomarkers of cardiovascular risk in type 2 diabetes with rosiglitazone added to metformin compared with dose escalation of metformin: an EMPIRE trial sub-study. Abstract: OBJECTIVE: To compare the effects of rosiglitazone added to metformin with dose escalation of metformin on cardiovascular risk biomarkers in type 2 diabetes mellitus. RESEARCH DESIGN AND METHODS: Cardiovascular biomarkers were assessed in a sub-population of 122 subjects with type 2 diabetes mellitus (mean age 54.6 and 56.0 years, BMI 34.7 and 32.1 kg/m2; for the rosiglitazone plus metformin and metformin groups, respectively) from the multicenter (63 centers in the USA), double-blind, randomized parallel-group Escalation of Metformin theraPy vs. Initiation of Rosiglitazone Early (EMPIRE) study. Treatment group sizes were slightly imbalanced owing to central, rather than local, randomization. Subjects receiving metformin 1000 mg/day at baseline were randomized to rosiglitazone 4 mg/day plus metformin 1000 mg/day (RSG + MET) or metformin 1500 mg/day (up-titrated MET) for 24 weeks. At 8-weeks, rosiglitazone was increased to 8 mg/day in RSG + MET recipients and metformin to 2000 mg/day in up-titrated MET recipients. RESULTS: Reductions from baseline in HbA1c at week 24 (mean +/- SD) occurred in both groups (RSG + MET: -0.61% +/- 1.16%; up-titrated MET: -0.65% +/- 1.18%). Post-prandial glucose levels (AUC(0-3h)) decreased with RSG + MET (-3.5 mmol/L.h; 95% confidence interval [CI]: -5.2 to -1.8) and up-titrated MET (-1.3 mmol/L.h; 95% CI: -3.8 to 1.1). Homeostasis Model Assessment (HOMA)-estimated insulin sensitivity increased by 37.7% (95% CI: 22.8 to 54.5) in RSG + MET and 6.9% (95% CI: -6.2 to 21.9) in up-titrated MET recipients. RSG + MET reduced C-reactive protein (CRP; -23.9%; 95% CI: -40.4 to -2.8), plasminogen activator inhibitor-1 (PAI-1) activity (-30.1%; 95% CI: -44.5 to -11.9), PAI-1 antigen (-15.5%; 95% CI: -28.3 to -0.3) and matrix metalloproteinase-9 (MMP-9; -13.8%; 95% CI: -25.1 to -0.9), but increased tumor necrosis factor-alpha (TNF-alpha; 27.0%; 95% CI: 6.8 to 50.9). Corresponding values for up-titrated MET were CRP -9.3% (95% CI: -36.9 to 30.2), PAI-1 activity -7.2% (95% CI: -28.2 to 20.0), PAI-1 antigen -1.5% (95% CI: -17.4 to 17.5), MMP-9 29.0% (95% CI: -1.3 to 68.6) and TNF-alpha -6.0% (95% CI: -22.0 to 13.2). CONCLUSIONS: These results suggest that rosiglitazone plus metformin has positive cardiovascular effects against a background of similar glycemic improvements.

Title: Red cell peroxide metabolism in diabetes mellitus. Abstract: In a group of normal controls and in a group of diabetics subdivided for type we evaluated the following red blood cell parameters: superoxide dismutase (SOD), glutathione peroxidase (GSH.Px), catalase (C-ase), glutathione content (GSH) and membrane-protein-sulphydryl groups (P-SH). There was no difference in the enzymatic activities of superoxide dismutase, glutathione peroxidase and catalase in normals and in the diabetics. However, the erythrocyte GSH content as well as membrane P-SH groups discriminate the normals from diabetics and also the diabetics subdivided for type. None of these parameters was related to the erythrocyte filterability considered as a reflection of the red blood cell deformability. These findings reveal that the diabetic red blood cell is less protected from oxidant agents.

Title: Prospective cohort study of type 2 diabetes and the risk of Parkinson's disease. Abstract: OBJECTIVE: To evaluate the association between type 2 diabetes and newly reported Parkinson's disease. RESEARCH DESIGN AND METHODS: Our study included 21,841 participants in the Physicians' Health Study, a cohort of U.S. male physicians. Diabetes and Parkinson's disease were self-reported via questionnaire. We used time-varying Cox regression to calculate adjusted relative risk (RR) for Parkinson's disease. RESULTS: Over 23 years, 556 individuals with Parkinson's disease were identified. Subjects with diabetes had an increased Parkinson's disease risk (multivariable-adjusted RR 1.34 [95% CI 1.01-1.77]). The association remained significant after exclusion of those with known vascular disease. The diagnosis of diabetes was clustered around the diagnosis of Parkinson's disease and was more apparent among men with short diabetes duration and those without complications from diabetes. CONCLUSIONS: Results of this large prospective study in men do not suggest that diabetes is a preceding risk factor for Parkinson's disease. Whether the positive association may be explained by ascertainment bias or a common underlying biological mechanism remains to be established.

Title: The effect of liraglutide, a long-acting glucagon-like peptide 1 derivative, on glycemic control, body composition, and 24-h energy expenditure in patients with type 2 diabetes. Abstract: OBJECTIVE: Glucagon-like peptide (GLP)-1 is a gut hormone that exerts incretin effects and suppresses food intake in humans, but its therapeutic use is limited due to its short half-life. This was a randomized, double-blind, parallel-group, placebo-controlled trial investigating the effect of the long-acting GLP-1 derivative liraglutide (NN2211) on glycemic control, body weight, body composition, and 24-h energy expenditure in obese subjects with type 2 diabetes. RESEARCH DESIGN AND METHODS: Thirty-three patients (mean +/- SD) aged 60.0 +/- 9.5 years, with HbA(1c) 7.5 +/- 1.2% and BMI 36.6 +/- 4.1 kg/m(2), were randomized to treatment with a single daily subcutaneous dose of 0.6 mg liraglutide (n = 21) or placebo (n = 12) for 8 weeks. In addition to weight and glycemic parameters, body composition was assessed by dual-energy X-ray absorptiometry (DEXA) scanning and 24-h energy expenditure in a respiratory chamber. RESULTS: After 8 weeks, liraglutide reduced fasting serum glucose (liraglutide, -1.90 mmol/l, and placebo, 0.27 mmol/l; P = 0.002) and HbA(1c) (liraglutide, -0.33%, and placebo, 0.47%; P = 0.028) compared with placebo. No change in body weight was detected (liraglutide, -0.7 kg, and placebo, -0.9 kg; P = 0.756). There was a nonsignificant trend toward a decrease in total fat mass (liraglutide, -0.98%, and placebo, -0.12%; P = 0.088) and toward an increase in lean body mass (liraglutide, 1.02%, and placebo, 0.23%; P = 0.118) in the liraglutide group compared with the placebo group. Twenty-four-hour energy expenditure was unaffected by the treatment (liraglutide, -12.6 kJ/h, and placebo, -13.7 kJ/h; P = 0.799). CONCLUSIONS: Eight weeks of 0.6-mg liraglutide treatment significantly improved glycemic control without increasing weight in subjects with type 2 diabetes compared with those on placebo. No influence on 24-h energy expenditure was detected.

Title: Association of diabetes-related emotional distress with diabetes treatment in primary care patients with Type 2 diabetes. Abstract: AIMS: To characterize the determinants of diabetes-related emotional distress by treatment modality (diet only, oral medication only, or insulin). METHODS: A total of 815 primary care patients with Type 2 diabetes completed the Problem Areas in Diabetes (PAID) Scale and other questions. We linked survey data to a diabetes clinical research database and used linear regression models to assess the associations of treatment with PAID score. RESULTS: PAID scores were significantly higher among insulin-treated (24.6) compared with oral-treated (17.8, P < 0.001) or diet-treated patients (14.7, P < 0.001), but not different between oral- vs. diet-treated patients (P = 0.2). Group scores remained similar, but the statistical significance of their differences was reduced and ultimately eliminated after sequential adjustment for diabetes severity, HbA(1c), body mass index, regimen adherence, and self-blood-glucose monitoring. Insulin-treated patients reported significantly higher distress than oral- or diet-treated patients on 16 of 20 PAID items. 'Worrying about the future' and 'guilt/anxiety when ... off track with diabetes' were the top two serious problems (PAID >or= 5) in all treatment groups. Not accepting diabetes diagnosis was a top concern for oral- and diet-treated patients, and unclear management goals distressed diet-treated patients. CONCLUSIONS: Primary care patients treated with insulin reported higher diabetes-related emotional distress compared with oral- or diet-treated patients. Greater distress was largely explained by greater disease severity and self-care burdens. To improve diabetes-specific quality of life, clinicians should address patients' sense of worry and guilt, uncertain acceptance of diabetes diagnosis, and unclear treatment goals.

Title: Structural and functional analysis of pancreatic islets preserved by pioglitazone in db/db mice. Abstract: To evaluate preventive effects of pioglitazone on pancreatic beta-cell damage in C57BL/KsJ db/db mice, an obese diabetic animal model, the pancreatic islets were compared morphologically between pioglitazone-treated (100 mg/kg daily po) and untreated db/db mice (n = 7 for each) after a 12-wk intervention (6-18 wk of age). The fasting blood glucose level was significantly improved by the treatment with pioglitazone (260 +/- 12 vs. 554 +/- 62 mg/dl, P < 0.05). The islet mass in the pancreas was significantly greater in pioglitazone-treated mice than in untreated mice (10.2 +/- 1.1 vs. 4.6 +/- 0.2 mg, P < 0.01). Subsequently, biochemical and physiological analyses of the beta-cell function were employed using pioglitazone-treated and untreated db/db mice (n = 6 for each) and pioglitazone-treated and untreated db/+ mice (n = 6 for each). After 2 wk of treatment (10-12 wk of age), the plasma levels of triglyceride and free fatty acid were significantly decreased, whereas the plasma adiponectin level increased significantly compared with the untreated group (65.2 +/- 18.0 vs. 18.3 +/- 1.3 microg/ml, P < 0.05). Pioglitazone significantly reduced the triglyceride content in the islets (43.3 +/- 3.6 vs. 65.6 +/- 7.6 ng/islet, P < 0.05) with improved glucose-stimulated insulin secretion. Pioglitazone showed no significant effects on the biochemical and physiological parameters in db/+ mice. The present study first demonstrated that pioglitazone prevents beta-cell damage in an early stage of the disease progression in db/db mice morphologically and physiologically. Our results suggest that pioglitazone improves glucolipotoxicity by increasing insulin sensitivity and reducing fat accumulation in the pancreatic islets.

Title: Mediators of inflammation in children with type I diabetes mellitus: cytokines in type I diabetic children. Abstract: OBJECTIVES: Recent evidence favors primary role of cellular autoimmunity and its humoral mediators in pathogenesis and following Type I diabetes mellitus (DM). The present study was carried out to investigate serum concentrations of C-reactive protein (CRP), interleukin (IL)-6, IL-8 and tumor necrosis factor (TNF)-alpha in children with type I DM. Potential role of lipid metabolism, glycemic control, body mass index (BMI) and disease duration were evaluated. DESIGN AND METHODS: Thirty-five children with type I DM and 30 age and gender matched nondiabetic controls were recruited for this study. RESULTS: Circulating IL-8 levels were elevated in children with type I DM (12.7 +/- 1.7 pg/mL) compared with nondiabetic controls (5.5 +/- 0.3 pg/mL) and the difference remained significant after adjustment for cofactors and covariates (p: 0.033). Although statistically insignificant serum CRP concentrations were slightly higher in diabetic children (p: 0.075). Serum TNF-alpha and IL-6 levels were comparable in diabetic and nondiabetic groups. However newly diagnosed (<1 yr) cases had higher TNF-alpha and IL-6 levels compared to cases with longer standing DM. In diabetic children BMI was independently associated with an increase in serum IL-8 levels. Serum CRP, lipids, apolipoproteins and glycemic control were not significant predictors of cytokine concentrations in children with type I DM. CONCLUSION: Circulating levels of IL-8 were elevated and were correlated with BMI in children with type I DM, hinting perhaps at adipose tissue as a site of production. Elevated systemic IL-6 and TNF-alpha were limited to newly diagnosed cases suggesting activation of the inflammatory immune response system at early stages of the disease.

Title: The effects of acute hypoglycemia on relative cerebral blood flow distribution in patients with type I (insulin-dependent) diabetes and impaired hypoglycemia awareness. Abstract: To examine the hypothesis that in diabetic patients with impaired hypoglycemia awareness the relative regional distribution of cerebral blood flow (rCBF) would be abnormal in a specific area, namely the frontal lobes, rCBF was examined in 20 type I diabetic patients, of whom 10 had a normal awareness of hypoglycemia and 10 had a history of impaired hypoglycemia awareness. rCBF was determined sequentially using single photon emission computed tomography (SPECT) during (1) normoglycemia (arterialized blood glucose 4.5 mmol. L-1) and (2) hypoglycemia (blood glucose 2.5 mmol.L-1) induced by a hyperinsulinemic glucose clamp technique. Distribution of the isotope, 99mTc-Exametazime, was detected using a single-slice multi-detector head scanner. A split-dose technique was used, with 250 MBq being injected during steady-state normoglycemia and 250 MBq during subsequent hypoglycemia. rCBF was estimated in 30 regions of interest, derived from a standard neuroanatomical atlas on two parallel slices at 40 and 60 mm above the orbitomeatal line (OML). No between-group differences in the pattern of overall rCBF or changes in regional tracer uptake were demonstrated. In comparison to the rCBF during normoglycemia, both patient groups exhibited significant changes in the pattern of rCBF during hypoglycemia, with increments of rCBF to both superior frontal cortices and the right thalamus and reduced rCBF to the right posterior cingulate cortex and the right putamen. This pattern of relative redistribution of rCBF during hypoglycemia was preserved in patients who had impaired hypoglycemia awareness.

Title: Early markers of the renal complications of insulin dependent diabetes mellitus. Abstract: We investigated the associations between albuminuria, metabolic control, glomerular filtration, blood pressure, and platelet function in children with insulin dependent diabetes mellitus. The geometric mean (95% tolerance levels) albumin excretion (expressed as the geometric mean albumin to creatinine ratio on two overnight urine collections (UA/UC], in 60 diabetic children was 0.72 (0.80-6.9) mg/mmol, significantly greater than in 45 normal children (geometric mean 0.41 (0.14-1.17]. Mean (SD) glomerular filtration rate, measured by 51Cr edetic acid clearance during constant infusion, was significantly greater in diabetic children (129 (20) ml/min/1.73 m2) compared with normal controls (109 (13]. Mean (SD) renal length for height standard deviation score was +0.25 (1.1); systolic blood pressure standard deviation score was 0.15 (0.65), and diastolic blood pressure was 0.51 (0.82). Spontaneous platelet aggregation, expressed as percentage fall in platelet count in stirred whole blood after 2 minutes was 17.8 (9.2)% in the diabetic compared with 12.3 (7.9)% in normal children. UA/UC correlated with renal length and of the children with UA/UC above the normal range, 70% also had a glomerular filtration rate above the normal range. There was a weak correlation between UA/UC and glycated haemoglobin (HbA1c). All children with spontaneous platelet aggregation above normal had had diabetes for more than seven years. These cross sectional data define some of the early markers and inter-relationships that may be important in the development of nephropathy.

Title: [Tissue-type plasminogen activator and its inhibitor (PAI-1) in plasma in cases of non-insulin-dependent diabetes mellitus (NIDDM)]. Abstract: Parameters of fibrinolysis, including plasminogen, alpha 2 plasmin-inhibitor (alpha 2 PI), tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) antigens, and fibrinogen were assayed in 53 patients (28 women and 27 men; mean age: 64 years, age range: 32-87 years) with non-insulin-dependent diabetes mellitus (NIDDM). The control group was similarly aged (mean age: 60.4 years, age range: 38-81). The levels of t-PA and t-PA/PAI-1 ratio of the diabetic group (mean +/- SD; 9.8 +/- 4.3 ng/ml, 0.94 +/- 0.47, respectively) were significantly higher than that of the control group (5.5 +/- 2.5 ng/ml, 0.51 +/- 0.23, respectively). The increased levels of t-PA antigen and t-PA/PAI-1 ratio in diabetics mean that free t-PA has been released. However, there was no significant difference in the level of PAI-1 between the diabetic group (12.9 +/- 6.4 ng/ml) and the control group (12.1 +/- 5.6 ng/ml). Levels of fibrinogen, plasminogen and alpha 2 PI in plasma were not different in the two groups. Duration of the disease, levels of glycosylated hemoglobin, differences in treatment and presense of diabetic nephropathy or retinopathy did not affect the fibrinolytic parameters. The levels of fibrinogen was higher in those with nephropathy than in the diabetics without nephropathy and retinopathy (p less than 0.05). There were no significant differences in the levels of t-PA, t-PA/PAI-1 ratio and PAI-1 between younger (less than 65 years) and older (65 years or more) subjects, in either the control or diabetic groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Title: Decreased sensitivity of contraction to changes of intracellular pH in papillary muscle from diabetic rat hearts. Abstract: 1. The relationship between intracellular pH (pHi) and contractile activity was investigated in papillary muscles isolated from right ventricle of normal and streptozotocin (STZ)-induced diabetic rats. pHi changes induced by 20 mM-NH4Cl were recorded with H(+)-sensitive microelectrodes. 2. An increase in pHi of approximately 0.20 pH units on exposure to NH4Cl led to an increase of the maximum developed tension, which was 707.8 +/- 57.5% (mean +/- S.E. of mean, n = 10) of control in normal muscles and 271 +/- 16.3% (n = 10) in diabetic muscles. On the other hand, acidosis induced by NH4Cl withdrawal was associated with a fall in developed tension to 48.2 +/- 6.7% of control in diabetic muscles, as compared to 79.2 +/- 8% in normal muscles. 3. The decrease in tension associated with acidosis was rapidly followed (in approximately 2 min) by a transient redevelopment of force, which peaked at 80.2 +/- 8.6% of control in the diabetic muscles as compared to 153.5 +/- 11.7% in normal papillary muscles. The peak of this secondary positive inotropy coincided in both groups of muscles with the maximum decrease of pHi, i.e. -0.40 +/- 0.02 and -0.28 +/- 0.04 pH units in diabetic and normal muscles, respectively. 4. Caffeine (10 mM), which had a marked positive inotropic effect in both groups of muscles, abolished the transient recovery of tension occurring after NH4Cl withdrawal. Ryanodine (2 microM) which had a marked negative inotropic effect on both normal and diabetic papillary muscles, also suppressed the transient recovery of tension. 5. The presence of amiloride (1 mM) during acidosis induced by NH4Cl withdrawal abolished the observed differences in developed tension, in particular the transient recovery of tension, between normal and diabetic muscles, as it abolished the differences in the amplitude of pHi decrease and in the time course of pHi recovery. 6. The presence of 2',4'-dichlorobenzamil amiloride (40 microM) significantly and similarly delayed and reduced the amplitude of transient recovery of tension in both normal and diabetic papillary muscles. 7. We conclude that STZ-induced diabetes induces a decrease in pHi sensitivity of contractile force. This may be the consequence of a change in sarcoplasmic reticulum (SR) composition and function, and may also indirectly result from changes in Na(+)-H+ exchange activity, particularly during intracellular acidosis.

Title: Genetic susceptibility to the development of spontaneous insulin-dependent diabetes mellitus in the rat. Abstract: Spontaneous insulin-dependent diabetes mellitus in the rat is a multigenic, multifactorial condition. We have identified three phenotypic characteristics of the syndrome. The first is an association with the RT1u haplotype of the rat major histocompatibility complex. A single RT1u haplotype is permissive, although the relative risk of developing the disease is increased when the animal is homozygous. An immunoregulatory defect, which is characterized phenotypically by a severe T lymphocyte depletion, behaves as if it were regulated by a single autosomal recessive gene which segregates independently of the RT1. The third phenotype characteristic is the presence of lymphocytic infiltration of the pancreas. The genetics of this characteristic have not been delineated, although there is evidence that it behaves as a dominant. In addition to the requirement for several genes, environmental events are important for full expression of the syndrome.

Title: Increased reduction in fasting C-peptide is associated with islet cell antibodies in type 1 (insulin-dependent) diabetic patients. Abstract: A cohort of 82 patients with Type 1 (insulin-dependent) diabetes was followed prospectively for 24 months, and 54 of them for 30 months, to study the relationship between fasting levels of immunoreactive C-peptide and titres of islet cell antibodies. After diagnosis, fasting C-peptide rose temporarily for 1-6 months of insulin therapy and declined continuously thereafter. While islet cell antibodies were present among 55% of the newly diagnosed patients, only 31% remained positive at 30 months. Their antibody titres decreased from 1:81 at diagnosis to 1:3. Only 3 patients (4%) who were islet cell antibody negative at diagnosis became positive later. The median C-peptide values among the persistently islet cell antibody positive patients decreased from 0.11 pmol/ml at 18 months, to 0.09 pmol/ml at 24 months, to 0.06 pmol/ml at 30 months compared to 0.18 (p = 0.04), 0.15 (p = 0.05) and 0.16 (p less than 0.003) pmol/ml, respectively, for the islet cell antibody negative patients. The median slope for the latter was -0.09 compared to -0.19 for the islet cell antibody positive patients (p = 0.01). These differences were reflected in increasing dosages of insulin, since patients remaining antibody-positive for 30 months were given 1.3-1.4 times more insulin (p = 0.01-0.004) than the antibody negative patients. This study demonstrates that islet cell antibodies may be a useful marker for predicting an increased rate by which endogenous B cell function is lost in Type 1 diabetes.

Title: Interaction effect between common polymorphisms in PPARgamma2 (Pro12Ala) and insulin receptor substrate 1 (Gly972Arg) on insulin sensitivity. Abstract: The Pro12Ala polymorphism in the peroxisome proliferator-activated receptor (PPAR) gamma2 gene is associated with a reduced risk of type 2 diabetes. A beneficial effect on insulin sensitivity is reported in some but not all populations. It is possible that this genetic variant produces a characteristic phenotype only against a certain genetic background. We therefore tested the hypothesis that carriers of the Ala allele of PPARgamma2 exhibit a different phenotype against the background of the Gly972Arg polymorphism in the insulin receptor substrate (IRS) 1. We determined insulin sensitivity in the four combinations defined by the absence or presence of the polymorphic allele (healthy, glucose tolerant subjects), by the oral glucose tolerance test (OGTT; using a validated index, n=318) and hyperinsulinemic clamp ( n=201). Insulin sensitivity was not or was only marginally different between Pro/Pro and X/Ala in the overall population. Interestingly, using the OGTT index, insulin sensitivity was significantly greater in X/Ala (PPARgamma2) + X/Arg (IRS-1) than in Pro/Pro (PPARgamma2) + X/Arg (IRS-1). On the other hand, insulin sensitivity was similar in the X/Ala (PPARgamma2) + Gly/Gly (IRS-1 972) and the Pro/Pro (PPARgamma2) + Gly/Gly (IRS-1). The results were practically identical using insulin sensitivity from the clamp. In conclusion, the Arg972 (IRS-1) background produced a marked difference in insulin sensitivity between X/Ala and Pro/Pro (PPARgamma) which was not present in the whole population or against the Gly972 (IRS-1) background. This suggests that the Ala allele of PPARgamma2 becomes particularly advantageous against the background of an additional, possibly disadvantageous genetic polymorphism. Allowing for gene-gene interaction effects may reveal novel information regarding metabolic effects of genetic variants.

Title: Effect of lithium on plasma glucose, insulin and glucagon in normal and streptozotocin-diabetic rats: role of glucagon in the hyperglycaemic response. Abstract: 1. Lithium salts, used in the treatment of affective disorders, may have adverse effects on glucose tolerance in man, and suppress glucose-stimulated insulin secretion in rats. 2. To study the interaction of these effects with pre-existing diabetes mellitus, plasma glucose and insulin responses to lithium chloride were measured in male Wistar rats made diabetic with intraperitoneal streptozotocin, and in normal controls. 3. In both normal and diabetic anaesthetized rats, intravenous lithium (4 mEq kg-1) caused a rise in plasma glucose. In absolute terms, the rise was greater in diabetic (5.2 mmol l-1) than in normal rats (2.3 mmol l-1). 4. Plasma insulin concentrations were reduced by lithium in normal rats, but the low insulin concentrations measured in the diabetic rats were not significantly changed. 5. After intravenous glucose (0.5 g kg-1), lithium-treated diabetic rats showed a second rise in plasma glucose at 60-90 min without any insulin response, while normal rats showed typically reduced insulin responses and initial glucose disappearance rates. 6. Intravenous glucose reduced plasma glucagon concentrations to a greater extent in normal than in diabetic rats, but lithium induced an equal rise in plasma glucagon in both groups, with a time-course similar to that of the hyperglycaemic effect. 7. The hyperglycaemic action of lithium is greater in the hypoinsulinaemic diabetic rats and appears to involve a stimulation of glucagon secretion in both normal and diabetic animals.

Title: The effect of intensive glycemic treatment on coronary artery calcification in type 1 diabetic participants of the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Study. Abstract: The Epidemiology of Diabetes Interventions and Complications (EDIC) study, an observational follow-up of the Diabetes Control and Complications Trial (DCCT) type 1 diabetes cohort, measured coronary artery calcification (CAC), an index of atherosclerosis, with computed tomography (CT) in 1,205 EDIC patients at approximately 7-9 years after the end of the DCCT. We examined the influence of the 6.5 years of prior conventional versus intensive diabetes treatment during the DCCT, as well as the effects of cardiovascular disease risk factors, on CAC. The prevalences of CAC >0 and >200 Agatston units were 31.0 and 8.5%, respectively. Compared with the conventional treatment group, the intensive group had significantly lower geometric mean CAC scores and a lower prevalence of CAC >0 in the primary retinopathy prevention cohort, but not in the secondary intervention cohort, and a lower prevalence of CAC >200 in the combined cohorts. Waist-to-hip ratio, smoking, hypertension, and hypercholesterolemia, before or at the time of CT, were significantly associated with CAC in univariate and multivariate analyses. CAC was associated with mean HbA(1c) (A1C) levels before enrollment, during the DCCT, and during the EDIC study. Prior intensive diabetes treatment during the DCCT was associated with less atherosclerosis, largely because of reduced levels of A1C during the DCCT.

Title: Characterization of a linear epitope within the human pancreatic 64-kDa glutamic acid decarboxylase and its autoimmune recognition by sera from insulin-dependent diabetes mellitus patients. Abstract: A 2.0-kb cDNA coding for the full-length 64-kDa human glutamic acid decarboxylase (GAD64) was isolated from a pancreatic carcinoma cDNA library by oligonucleotide screening, polymerase-chain-reaction amplification and subsequently characterized by sequence analysis. Five overlapping fragments of GAD64 cDNA were constructed into the vector pH6EX3, allowing the highly efficient expression of corresponding fusion proteins with a histidine hexapeptide as an affinity ligand at their N-termini in Escherichia coli. The recombinant GAD64 fragments were analysed by Western blotting using sera from patients with early onset of insulin-dependent diabetes mellitus (IDDM). We found that at least 20% of the patients with an onset of IDDM have developed autoantibodies which can specifically recognize a linear antigenic epitope within the GAD64. With a selected IDDM serum, an antigenic epitope was localized in a region of 31 amino acids located at the C-terminus of GAD64, using epitope mapping techniques, and it was characterized. The possibility of using recombinant GAD64 for the development of an immunoassay for a predictive diagnosis of IDDM is discussed.

Title: Role of viruses in type I diabetes. Abstract: Viral infections frequently elicit strong cellular and humoral immune responses. This bears the inherent danger of co-activating autoreactive lymphocytes, either through bystander activation by cytokines or through direct sharing of conformational determinants between self and virus (mimicry). Autoimmune diseases could then result, even after clearance of the viral infection, if enough autoreactive cells are activated. Alternatively, viral infection of antigen presenting cells can locally enhance inflammation and drive autoreactive lymphocytes. Evidence for these mechanisms, as well as emerging therapeutic concepts, will be discussed.

Title: The association of non-insulin-dependent diabetes mellitus with perceived quality of life in a biethnic population: the San Luis Valley Diabetes Study. Abstract: OBJECTIVES: This study evaluated the association between quality of life and non-insulin-dependent diabetes mellitus (NIDDM) status, and whether this association differs between Hispanics and non-Hispanic Whites. METHODS: Between 1986 and 1989, cross-sectional data on perceived quality of life (PQOL) were collected from 223 persons with NIDDM and 753 non-diabetic subjects. RESULTS: After adjustment, persons with NIDDM rated their PQOL significantly lower than did control subjects. The relationship of diabetes and PQOL did not differ by ethnicity. The number of complications of diabetes was not associated with lower PQOL scores. CONCLUSIONS: Control and treatment strategies should reflect an understanding of the impact that diabetes has on social functioning, leisure activities, and physical and mental health.

Title: Residual insulin production, glycaemic control and prevalence of microvascular lesions and polyneuropathy in long-term type 1 (insulin-dependent) diabetes mellitus. Abstract: The aim of the present study was to evaluate the role of residual insulin production in long-term Type 1 (insulin-dependent) diabetes mellitus. Ninety-seven patients with a disease duration of 9-16 years and onset before the age of 30 years were studied. C-peptide excretion in 24-h urine samples was measured as an indicator of residual insulin production. Thirty-five patients (36%) excreted C-peptide (greater than or equal to 0.2 nmol); as many as possible of them were carefully matched with a non-excretor patient with regard to age at onset of diabetes and disease duration. Twenty-nine pairs were obtained, and 22 of them agreed to participate in further investigations of glycaemic control and microangiopathic lesions. The patients who excreted C-peptide had significantly lower HbA1c than the non-excretor group, 6.9 +/- 0.3% vs 7.9 +/- 0.3%, (p less than 0.025). Moderate-to-advanced background retinopathy was found in 2 patients in the excretor group and in 7 patients in the non-excretor group. Microalbuminuria [ratio of albumin: creatinine (mg/l:mmol/l) greater than or equal to 5] was found in 1 and in 5 patients, respectively, while proteinuria [ratio of protein: creatinine (mg/l:mmol/l X 10) greater than or equal to 136] was found in 0 and in 4 patients, respectively. Microalbuminuria and/or proteinuria was found in 7 of the non-excretor group as compared to 1 in the excretor group (p = 0.046).(ABSTRACT TRUNCATED AT 250 WORDS)

Title: Cutting edge: homologous recombination of the MHC class I K region defines new MHC-linked diabetogenic susceptibility gene(s) in nonobese diabetic mice. Abstract: To localize the MHC-linked diabetogenic genes in the nonobese diabetic (NOD) mouse, a recombinational hotspot from the B10.A(R209) mouse was introduced to the region between the MHC class I K and class II A of the NOD mouse with the recombinational site centromeric to the Lmp2/Tap1 complex by breeding the two strains. Replacement of the NOD region centromeric to the recombinational site with the same region in R209 mice prevented the development of diabetes (from 71 to 3%) and insulitis (from 61 to 15%) in the N7 intra-MHC recombinant NOD mice. Similarly, the replacement of the NOD class II A, E and class I D region with the same region in R209 mice prevented the diseases (diabetes, from 71 to 0%; insulitis, from 61 to 3%). In addition to the MHC class II genes, there are at least two MHC-linked diabetogenic genes in the region centromeric to Lmp2.

Title: Amylin and insulin co-replacement therapy for insulin-dependent (type I) diabetes mellitus. Abstract: Amylin is a proteinaceous hormone secreted form insulin-producing pancreatic beta-cells following stimulation by food molecules such as glucose and arginine. Amylin decreases insulin-stimulated glucose uptake in skeletal muscle and counteracts the ability of insulin to suppress output of glucose from the liver. Substantial evidence supports the view that maylin is a second glucoregulatory hormone produced from islet beta-cells, which can modulate a number of metabolic processes also regulated by insulin. The islet beta-cell may therefore transmit a dual message to peripheral tissues through the two hormones, insulin and amylin. Like insulin, amylin is deficient in individuals with autoimmune diabetes mellitus. Since amylin can modulate processes of fuel metabolism in key tissues, amylin deficiency could contribute to the clinical course in patients with autoimmune diabetes. Here, I propose that amylin lack plays a significant role to promote the tendency to hypoglycemia and defective glycemic control characteristic of insulin-treated patients with autoimmune diabetes. Treatment of such diabetics with injections of amylin as well as insulin is being evaluated with the aim of lessening the incidence and severity of hypoglycemia and improving glycemic control.

Title: Effects of the new oral hypoglycaemic agent nateglinide on insulin secretion in Type 2 diabetes mellitus. Abstract: AIMS: The new non-sulphonylurea oral hypoglycaemic agent nateglinide has been shown to enhance insulin secretion in animals and in healthy human volunteers and thus offers a potential advance in the treatment of Type 2 diabetes mellitus. This study examined whether nateglinide can enhance insulin secretion, and particularly the first phase insulin response, in patients with Type 2 diabetes. METHODS: A double-blind, placebo-controlled trial, examining the effects of a single oral dose of 60 mg nateglinide, given 20 min prior to an intravenous glucose tolerance test (IGTT), on insulin secretion in 10 otherwise healthy Caucasian men with recently diagnosed Type 2 diabetes (duration since diagnosis 0-44 months). RESULTS: Insulin secretion (both overall and first phase) was significantly increased by nateglinide (P < 0.001), as were C-peptide (P < 0.001) and proinsulin (P < 0.001) secretion. Overall glucose concentrations following glucose challenge were lower after nateglinide than after placebo (P = 0.05). CONCLUSIONS: Nateglinide significantly increases insulin secretion in Type 2 diabetic patients, in particular restoring the first phase insulin response. Further study is necessary to determine the effects of chronic administration on insulin secretion and blood glucose concentration.

Title: Single-donor, marginal-dose islet transplantation in patients with type 1 diabetes. Abstract: CONTEXT: Islet allografts from 2 to 4 donors can reverse type 1 diabetes. However, for islet transplants to become a widespread clinical reality, diabetes reversal must be achieved with a single donor to reduce risks and costs and increase the availability of transplantation. OBJECTIVE: To assess the safety of a single-donor, marginal-dose islet transplant protocol using potent induction immunotherapy and less diabetogenic maintenance immunosuppression in recipients with type 1 diabetes. A secondary objective was to assess the proportion of islet transplant recipients who achieve insulin independence in the first year after single-donor islet transplantation. DESIGN, SETTING, AND PARTICIPANTS: Prospective, 1-year follow-up trial conducted July 2001 to August 2003 at a single US center and enrolling 8 women with type 1 diabetes accompanied by recurrent hypoglycemia unawareness or advanced secondary complications. INTERVENTIONS: Study participants underwent a primary islet allotransplant with 7271 (SD, 1035) islet equivalents/kg prepared from a single cadaver donor pancreas. Induction immunosuppression was with antithymocyte globulin, daclizumab, and etanercept. Maintenance immunosuppression consisted of mycophenolate mofetil, sirolimus, and no or low-dose tacrolimus. MAIN OUTCOME MEASURES: Safety (assessed by monitoring the severity and duration of adverse events) and efficacy (assessed by studying the recipients' insulin requirements, C-peptide levels, oral and intravenous glucose tolerance results, intravenous arginine stimulation responses, glycosylated hemoglobin levels, and hypoglycemic episodes) associated with the study transplant protocol. RESULTS: There were no serious, unexpected, or procedure- or immunosuppression-related adverse events. All 8 recipients achieved insulin independence and freedom from hypoglycemia. Five remained insulin-independent for longer than 1 year. Graft failure in 3 recipients was preceded by subtherapeutic sirolimus exposure in the absence of measurable tacrolimus trough levels. CONCLUSIONS: The tested transplant protocol restored insulin independence and protected against hypoglycemia after single-donor, marginal-dose islet transplantation in 8 of 8 recipients. These results may be related to improved islet engraftment secondary to peritransplant administration of antithymocyte globulin and etanercept. These findings may have implications for the ongoing transition of islet transplantation from clinical investigation to routine clinical care.

Title: Maternal microchimerism in peripheral blood in type 1 diabetes and pancreatic islet beta cell microchimerism. Abstract: Maternal cells have recently been found in the circulation and tissues of mothers' immune-competent children, including in adult life, and is referred to as maternal microchimerism (MMc). Whether MMc confers benefits during development or later in life or sometimes has adverse effects is unknown. Type 1 diabetes (T1D) is an autoimmune disease that primarily affects children and young adults. To identify and quantify MMc, we developed a panel of quantitative PCR assays targeting nontransmitted, nonshared maternal-specific HLA alleles. MMc was assayed in peripheral blood from 172 individuals, 94 with T1D, 54 unaffected siblings, and 24 unrelated healthy subjects. MMc levels, expressed as the genome equivalent per 100,000 proband cells, were significantly higher in T1D patients than unaffected siblings and healthy subjects. Medians and ranges, respectively, were 0.09 (0-530), 0 (0-153), and 0 (0-7.9). Differences between groups were evident irrespective of HLA genotypes. However, for patients with the T1D-associated DQB1*0302-DRB1*04 haplotype, MMc was found more often when the haplotype was paternally (70%) rather than maternally transmitted (14%). In other studies, we looked for female islet beta cells in four male pancreases from autopsies, one from a T1D patient, employing FISH for X and Y chromosomes with concomitant CD45 and beta cell insulin staining. Female islet beta cells (presumed maternal) formed 0.39-0.96% of the total, whereas female hematopoietic cells were very rare. Thus, T1D patients have higher levels of MMc in their circulation than unaffected siblings and healthy individuals, and MMc contributes to islet beta cells in a mother's progeny.

Title: Oxidative-nitrosative stress and poly(ADP-ribose) polymerase (PARP) activation in experimental diabetic neuropathy: the relation is revisited. Abstract: Poly(ADP-ribose) polymerase (PARP) activation, an important factor in the pathogenesis of diabetes complications, is considered a downstream effector of oxidative-nitrosative stress. However, some recent findings suggest that it is not necessarily the case and that PARP activation may precede and contribute to free radical and oxidant-induced injury. This study evaluated the effect of PARP inhibition on oxidative-nitrosative stress in diabetic peripheral nerve, vasa nervorum, aorta, and high glucose-exposed human Schwann cells. In vivo experiments were performed in control rats and streptozocin (STZ)-induced diabetic rats treated with and without the PARP inhibitor 3-aminobenzamide (ABA) (30 mg . kg(-1) . day(-1) i.p. for 2 weeks after 2 weeks of untreated diabetes). Human Schwann cells (HSC) (passages 7-10; ScienCell Research Labs) were cultured in 5.5 or 30 mmol/l glucose with and without 5 mmol/l ABA. Diabetes-induced increase in peripheral nerve nitrotyrosine immunoreactivity, epineurial vessel superoxide and nitrotyrosine immunoreactivities, and aortic superoxide production was reduced by ABA. PARP-1 (Western blot analysis) was abundantly expressed in HSC, and its expression was not affected by high glucose or ABA treatment. High-glucose-induced superoxide production and overexpression of nitrosylated and poly(ADP-ribosyl)ated protein, chemically reduced amino acid-(4)-hydroxynonenal adducts, and inducible nitric oxide synthase were decreased by ABA. We concluded that PARP activation contributes to superoxide anion radical and peroxynitrite formation in peripheral nerve, vasa nervorum, and aorta of STZ-induced diabetic rats and high- glucose-exposed HSC. The relations between oxidative-nitrosative stress and PARP activation in diabetes are bi- rather than unidirectional, and PARP activation cannot only result from but also lead to free radical and oxidant generation.

Title: Effect of troglitazone on body fat distribution in type 2 diabetic patients. Abstract: OBJECTIVE: Troglitazone was recently reported to specifically promote the differentiation of pre-adipocytes into adipocytes in vitro in subcutaneous fat only, indicating a relation to insulin-resistance-improving action of troglitazone. To expand on this finding, we investigated at the clinical level how long-term administration of troglitazone influences the body fat distribution in type 2 diabetic patients. RESEARCH DESIGN AND METHODS: Troglitazone (400 mg/day) was administered for 6 months to 30 type 2 diabetic patients whose glycemic control was poor. A total of 18 patients received diet therapy alone (in the single-treatment group, BMI 26.0 +/- 4.6, HbA1c 8.2 +/- 1.7%), and 12 patients concomitantly received glibenclamide (1.25-7.5 mg/day) (in the concomitant sulfonylurea group, BMI 25.4 +/- 4.7, HbA1c 9.2 +/- 1.2%). BMI, HbA1c, serum lipid level, and body fat distribution, which were determined by computed tomography (CT) scan at the umbilical level, were measured and compared before and after troglitazone treatment. RESULTS: During the 6-month troglitazone treatment, HbA1c levels decreased and BMI increased in both groups. As for body fat distribution in the single-treatment group, visceral fat area (VFA) decreased (from 118.3 +/- 54.3 to 101.1 +/- 50.8 cm2; P < 0.001), and subcutaneous fat area (SFA) increased (from 189.7 +/- 93.3 to 221.6 +/- 101.6 cm2; P < 0.001), resulting in a decrease in visceral/subcutaneous (V/S) ratio (from 0.74 +/- 0.48 to 0.50 +/- 0.32; P < 0.001). In the concomitant sulfonylurea group, VFA was unchanged (from 108.1 +/- 53.5 to 112.5 +/- 59.9 cm2), while SFA increased (from 144.6 +/- 122.0 to 180.5 +/- 143.5 cm2; P < 0.01), thereby decreasing the V/S ratio (from 0.91 +/- 0.46 to 0.77 +/- 0.44; P < 0.01). The serum triglyceride level and the area under glucose curve during the 75-g oral glucose tolerance test decreased significantly in the single-treatment group. CONCLUSIONS: According to our data, troglitazone appears to promote fat accumulation in the subcutaneous adipose tissue rather than in the visceral adipose tissue in mildly obese Japanese people with type 2 diabetes. This shift of energy accumulation from the visceral to subcutaneous adipose tissue may greatly contribute to the troglitazone-mediated amelioration of insulin resistance.

Title: Induction of type I diabetes by Kilham's rat virus in diabetes-resistant BB/Wor rats. Abstract: Type I diabetes mellitus is an autoimmune disease resulting from the interaction of genetic and environmental factors. A virus that was identified serologically as Kilham's rat virus (KRV) was isolated from a spontaneously diabetic rat and reproducibly induced diabetes in naive diabetes-resistant (DR) BB/Wor rats. Viral antigen was not identified in pancreatic islet cells, and beta cell cytolysis was not observed until after the appearance of lymphocytic insulitis. KRV did not induce diabetes in major histocompatibility complex-concordant and discordant non-BB rats and did not accelerate diabetes in diabetes-prone BB/Wor rats unless the rats had been reconstituted with DR spleen cells. This model of diabetes may provide insight regarding the interaction of viruses and autoimmune disease [corrected]

Title: Glycation of paraoxonase-1 inhibits its activity and impairs the ability of high-density lipoprotein to metabolize membrane lipid hydroperoxides. Abstract: AIMS: High-density lipoprotein (HDL) protects against atherosclerosis development. Defective functioning of HDL in Type 2 diabetes may be one cause of increased cardiovascular disease associated with Type 2 diabetes. HDL modulates low-density lipoprotein and cell membrane oxidation through the action of paraoxonase-1 (PON1), which is one of the major mechanisms by which HDL is anti-atherogenic. METHODS: We have compared the ability of HDL from Type 2 diabetic patients without coronary heart disease (CHD) (n = 36) to metabolize membrane lipid hydroperoxides with HDL from healthy control subjects (n = 19) and people with CHD but no diabetes (n = 37). RESULTS: HDL from subjects with Type 2 diabetes and CHD metabolized 20% less membrane hydroperoxides than HDL from control subjects (P < 0.05). The PON1-192RR was least efficient in all the study groups. PON1 was glycated in vivo: (7.5% control, 12% CHD, 17% Type 2 diabetes P < 0.01) with QQ isoforms most glycated. In vitro glycation of PON1 reduced its ability to metabolize membrane hydroperoxides by 50% (P < 0.001); however, glyoxidation reduced it by 80% (P < 0.001). In the control group only there was a significant negative correlation between PON1 activity and the ability of HDL to metabolize membrane hydroperoxides (r = -0.911, P < 0.001). CONCLUSIONS: HDL from Type 2 diabetic patients without CHD has decreased ability to metabolize membrane lipid hydroperoxides, which could lead to increased susceptibility to cardiovascular disease.

Title: Decline in incidence of epidemic glucose intolerance in Nauruans: implications for the "thrifty genotype". Abstract: Trends in the prevalence and incidence of non-insulin-dependent diabetes mellitus and impaired glucose tolerance were studied in Micronesian Nauruans aged 20 years and above, by linking glucose tolerance data collected during population surveys performed in 1975/1976, 1982, and 1987. Based on World Health Organization criteria, the age-standardized prevalence of non-insulin-dependent diabetes mellitus has remained relatively constant (24.0% in 1987), but the prevalence of impaired glucose tolerance has decreased significantly from 21.1% (95% confidence interval (CI) 17.0-25.3) in 1975/1976 to 8.7% (95% CI 7.1-10.3) in 1987. Between the periods 1975/1976-1982 and 1982-1987, the incidence of progression from normal glucose tolerance to either impaired glucose tolerance (incidence rate ratio (IRR) = 0.55, p less than 0.01) or non-insulin-dependent diabetes (IRR = 0.46, p less than 0.05) has decreased dramatically, while progression from impaired glucose tolerance to non-insulin-dependent diabetes has increased (IRR = 1.23). The overall age-standardized incidence of non-insulin-dependent diabetes has declined from 26.2 cases/1,000 person-years in 1975/1976-1982 to 22.5 cases/1,000 person-years in 1982-1987. As there were no changes in the frequency of recognized risk factors, the decline in incidence of glucose intolerance is probably due to the intensity of the epidemic in Nauru, which has already removed a high proportion of the genetically susceptible individuals from the pool with normal glucose tolerance. Coupled with the observations that mortality is higher and fertility lower in diabetic Nauruans across the age range, the observed decline in the incidence and prevalence of non-insulin-dependent diabetes mellitus and impaired glucose tolerance may presage a fall in the population frequency of the diabetic genotype, at least in its more severe form, as might be predicted on the basis of Neel's "thrifty genotype" hypothesis.

Title: Increased levels of ligands of Toll-like receptors 2 and 4 in type 1 diabetes. Abstract: AIMS/HYPOTHESIS: Type 1 diabetes is a proinflammatory state characterised by increased levels of circulating biomarkers of inflammation and monocyte activity. We have shown increased Toll-like receptor 2 (TLR2) and TLR4 expression and signalling in monocytes from type 1 diabetic patients. Several endogenous ligands of TLR2 and TLR4 have been identified; however, there is a paucity of data on levels of these endogenous ligands in diabetes. Thus, the aim of this study was to examine circulating levels of exogenous/endogenous ligands of TLR2 and TLR4 in type 1 diabetic patients and to compare these with the levels in matched healthy controls. METHODS: Healthy controls (n = 37) and type 1 diabetic patients (n = 34) were recruited, and a fasting blood sample was obtained. Circulating levels of endotoxin, heat-shock protein 60 (Hsp60), high-mobility group box 1 (HMGB1) and growth arrest-specific 6 (GAS6) proteins were assessed by ELISA, and TLR2 and TLR4 expression was determined by flow cytometry. RESULTS: Levels of the classical TLR4 ligand, endotoxin, were significantly elevated in type 1 diabetic patients compared with those in matched controls. Hsp60 and HMGB1 concentrations were also significantly increased in the patients (p < 0.01 and p < 0.001, respectively). No significant differences were observed in GAS6. CONCLUSIONS/INTERPRETATION: We report the novel observation that levels of ligands of TLR2 and TLR4 are significantly elevated in type 1 diabetes, and this, in concert with hyperglycaemia, accounts for the increase in TLR2 and TLR4 activity, underscoring the proinflammatory state of type 1 diabetes.

Title: Arabinoxylan fibre improves metabolic control in people with Type II diabetes. Abstract: OBJECTIVE: To determine whether diet supplementation with arabinoxylan-rich (AX)-fibre from wheat improves glycaemic control in Type II diabetes. DESIGN: Randomized, crossover intervention trial. SETTING: Monash Medical Centre. SUBJECTS: A total of 15 subjects with Type II diabetes. INTERVENTIONS: Over two 5-week periods, subjects supplemented their usual diet with control bread and muffins (50% whole wheat, 50% white flour) (control diet) or with AX-bread and muffins (50% whole wheat, 36% white flour, 14% AX fibre) (AX diet). Subjects completed a 7-day food diary. At 0 and 5 weeks, venous blood was collected for determination of fasting and 2 h glucose, insulin, fructosamine and blood lipids. Blood pressure, body weight and body fat were also determined. A 24 h faecal sample, from 12 subjects, was weighed and analysed for faecal polysaccharide as a marker for dietary compliance. RESULTS: Control and AX diets were similar except the AX diet supplied an additional 15.1 (12.0-18.5) (mean (95% confidence intervals)) g/day dietary fibre (P=0.000). Consumption of the AX diet increased faecal output by 61.5 (0.2-122.8) g/day (P=0.05) on a wet weight basis and significantly lowered fasting and 2 h plasma glucose, 2 h insulin and serum fructosamine (P=0.002, 0.000, 0.015, and 0.02, respectively). Blood lipids, body weight, fat mass and blood pressure remained unchanged. CONCLUSION: A supplement of 15 g/day of AX-rich fibre can significantly improve glycaemic control in people with Type II diabetes.

Title: Microalbuminuria prevalence varies with age, sex, and puberty in children with type 1 diabetes followed from diagnosis in a longitudinal study. Oxford Regional Prospective Study Group. Abstract: OBJECTIVE: The predictive value of microalbuminuria (MA) in children with type 1 diabetes has not been defined. We describe the natural history of MA in a large cohort of children recruited at diagnosis of type 1 diabetes. RESEARCH DESIGN AND METHODS: Between 1985 and 1996, 514 children (279 male) who developed type 1 diabetes before the age of 16 years (91% of those eligible from a region where ascertainment of new cases is 95%) were recruited for a longitudinal study with central annual assessment of HbAlc and albumin excretion (three urine samples). Dropout rates have been < 1% per year, and 287 children have been followed for > 4.5 years. RESULTS: MA (defined as albumin-to-creatinine ratio > or = 3.5 and > or = 4.0 mg/mmol in boys and girls, respectively) developed in 63 (12.8%) and was persistent in 22 (4.8%) of the subjects. The cumulative probability (based on the Kaplan-Meier method) for developing MA was 40% after 11 years. HbAlc was worse in those who developed MA than in others (mean difference +/- SEM: 1.1% +/- 0.2, P < 0.001). In subjects who had been 5-11 years of age when their diabetes was diagnosed, the appearance of MA was delayed until puberty, whereas of those whose age was < 5 years at diagnosis of diabetes, 5 of 11 (45%) developed MA before puberty. The adjusted proportional probability (Cox model) of MA was greater for female subjects (200%), after pubertal onset (310%), and with greater HbAlc (36% increase for every 1% increase in HbAlc). Despite earlier differences based on age at diagnosis of diabetes (< 5, 5-11, and > 11 years), the overall cumulative risks in these groups were similar (38 vs. 29 vs. 39%, respectively) after 10 years' duration of diabetes. CONCLUSIONS: Prepubertal duration of diabetes and prepubertal hyperglycemia contribute to the risk of postpubertal MA. The differences in rates of development of MA relating to HbAlc, sex, and age at diagnosis relative to puberty may have long-term consequences for the risk of subsequent nephropathy and for cardiovascular risk.

Title: Evaluation of delivery of enhanced diabetes care to patients of South Asian ethnicity: the United Kingdom Asian Diabetes Study (UKADS). Abstract: AIMS: We tested the hypothesis that enhanced care for diabetes, tailored to the needs of the South Asian community with Type 2 diabetes, would improve risk factors for diabetic vascular complications and ultimately reduce morbidity and mortality. PATIENTS AND METHODS: The study was a cluster randomized controlled trial (RCT) with general practice the unit of randomization. Six West Midlands general practices with a high proportion of South Asian patients were randomized to 'enhanced care' using Asian link workers and extra community diabetes specialist nurse sessions (intervention) or continued standard practice care (control). RESULTS: Of 401 patients recruited to the study, 361 (90%), comprising 178 from Coventry and 183 from Birmingham were eligible and included in the analyses. The mean age at baseline (standard deviation, SD) was 58.9 (11.7 years) with median (interquartile range; IQR) duration of diabetes 6.5 (3-11) years. At one year follow-up there was a significant difference in reduction of systolic (4.6 mmHg, P = 0.035) and diastolic blood pressure (3.4 mmHg, P = 0.003) and total cholesterol (0.4 mmol/l, P = 0.005), comparing the intervention and control groups. After adjusting for baseline measurement and age, only differential reduction in diastolic blood pressure remained significant. There was no significant change in HbA(1c) and no difference between the groups. CONCLUSIONS: Using link workers and extra community diabetes specialist nurse input together with treatment protocols in primary care might prove a useful strategy in working towards NSF targets for diabetes management. In this study, small reductions in blood pressure and cholesterol were achieved. Improvement in glycaemic control may require longer and possibly different strategies. Further research is required to evaluate fully the effectiveness, including the costs and longer term sustainability of culturally sensitive initiatives.

Title: HLA class I supertypes in type 1 diabetic children in an urban children's hospital. Abstract: Type 1 diabetes is an autoimmune disorder characterized by progressive destruction of insulin-secreting beta cells of the pancreas, in which CD8(+) T cells play a critical role. The diversity in the HLA alleles expressed among various racial and ethnic groups leads to great variability in antigen presentation and recognition by CD8(+) T cells in the context of MHC class I molecules. To date, studies aimed at identifying disease-relevant antigenic epitopes have focused on using mice transgenic for HLA-A*0201, a common allele, particularly among Caucasians. We present HLA class I typing data from 88 children with type 1 diabetes at the Children's Hospital at Montefiore, where the patient population is ethnically diverse, but largely minority. When categorized into the HLA supertypes A2, A3, B7, and C1, 77% of those studied have alleles belonging to at least one supertype, and of these patients, 65% do not belong to the A2 supertype, which is the supertype represented by the HLA-A*0201 allele. These results support the need for studies using HLA transgenic mice expressing MHC molecules representative of a variety of HLA supertypes, particularly when searching for antigenic epitopes applicable for study among largely urban, minority pediatric populations.

Title: Expression of a novel murine type I IFN in the pancreatic islets induces diabetes in mice. Abstract: IFN-kappa belongs to a recently identified subclass of type I IFNs. In this study, we report the cloning and preliminary characterization of the murine homologue of IFN-kappa. The gene encodes a 200-aa protein which is 38.5% homologous to human IFN-kappa. Murine IFN-kappa contains four cysteines in analogous positions to those observed in the IFN-alpha and an additional fifth unique cysteine, C174. The murine gene is located on chromosome 4, where other type I murine IFN genes, IFN-alpha and IFN-beta, are clustered. This region is syntenic with human chromosome 9 where the gene encoding IFN-kappa and the type I IFN gene cluster are found. Mouse IFN-kappa is expressed at low levels in peritoneal macrophages and its expression is up-regulated by dsRNA and IFN-gamma. Similar to previously reported transgenic mice carrying type I and type II IFNs, transgenic mice overexpressing murine IFN-kappa in the beta cells of the pancreas develop overt diabetes with hyperglycemia. Histological characterization of pancreatic islets from these transgenic mice showed inflammatory infiltrates with corresponding destruction of beta cells.

Title: Accumulation of long-chain acylcarnitine and 3-hydroxy acylcarnitine molecular species in diabetic myocardium: identification of alterations in mitochondrial fatty acid processing in diabetic myocardium by shotgun lipidomics. Abstract: Diabetic cardiomyopathy is the result of maladaptive changes in energy homeostasis. However, the biochemical mechanisms underlying dysfunctional lipid metabolism in diabetic myocardium are incompletely understood. Herein, we exploit shotgun lipidomics to demonstrate a 4-fold increase in acylcarnitines in diabetic myocardium, which was reversible upon insulin treatment. Analysis of acylcarnitine molecular species in myocardium unexpectedly identified acylcarnitine molecular species containing a mass shift of 16 amu in comparison to the anticipated molecular species. Synthesis of 3-hydroxy acylcarnitine identified the natural products as the 3-hydroxylated acylcarnitines through comparisons of diagnostic fragmentation patterns of synthetic and naturally occurring constituents using tandem mass spectrometry. Diabetes induced an increase of both calcium-independent phospholipase A(2) (iPLA(2)) mRNA and iPLA(2) activity in rat myocardium. Cardiac ischemia in myocardium genetically engineered to overexpress iPLA(2) dramatically increased the amount of acylcarnitine present in myocardium. Moreover, mechanism-based inactivation of iPLA(2) in either wild-type or transgenic myocardium ablated a substantial portion of the acylcarnitine increase. Collectively, these results identify discrete insulin remediable abnormalities in mitochondrial fatty acid processing in diabetic myocardium and identify iPLA(2) as an important enzymatic contributor to the pool of fatty acids that can be used for acylcarnitine synthesis and energy production in myocardium.

Title: Baseline characteristics of the randomised cohort from the Look AHEAD (Action for Health in Diabetes) study. Abstract: OBJECTIVE: The Look AHEAD (Action for Health in Diabetes) study is a 16-centre randomised clinical trial in overweight and obese individuals with type 2 diabetes, designed to evaluate the long-term effects (up to 11.5 years) of intensive weight loss intervention on the time to incidence of major cardiovascular events. RESEARCH DESIGN AND METHODS: Eligibility requirements are diagnosis of type 2 diabetes (determined by self-report and verification) in individuals aged 4574 years and body mass index (BMI) > 25 kg/m2 (> 27 kg/m2 if currently taking insulin). The intensive lifestyle intervention is designed to achieve and maintain weight loss through decreased caloric intake and increased physical activity. The study is designed to provide 90% probability of detecting an 18% difference in major cardiovascular disease event rates in patients randomised to the intensive lifestyle intervention compared to the control group receiving standard diabetes support and education. RESULTS: The 5,145 participants who were randomised between 2001 and 2004 were 63.3% white, 15.6% African-American, 13.2% Hispanic, 5.0% American Indian and 1.0% Asian-American, which closely paralleled the ethnic distribution of diabetes in the National Health and Nutrition Examination Survey (NHANES) 1999-2000 survey. Their average age at entry was 59+/-6.8 years (mean+/-SD), and 60% were women. There were 31.5% between 4555 years of age, 51.5% were 5665, and 17.0% were 6676 years of age. Some 15.4% of participants were taking insulin at the time of randomisation and 14.0% had a history of cardiovascular disease. More men (21.3%) than women (9.2%) had a history of cardiovascular disease. Few participants (4.4%) were current cigarette smokers, compared to 16.2% in the NHANES 1999-2000 survey. Furthermore, 65.0% of participants had a first-degree relative with diabetes. Overall, BMI averaged 36+/-5.9 kg/m2 at baseline, with 83.6% of the men and 86.1% of women having a BMI > 30 kg/m2 and 17.9% of men and 25.4% of women having a BMI > 40 kg/m2. CONCLUSIONS: The Look AHEAD study has successfully randomised a large cohort of participants who have type 2 diabetes with a wide distribution of age, obesity, ethnicity and racial background and will examine the effects of lifestyle intervention on the incidence of major cardiovascular events.

Title: Renal enlargement: comparative autoradiographic studies of 3H-thymidine uptake in diabetic and uninephrectomized rats. Abstract: Incorporation of 3H-thymidine into renal cortical tissue has been studied by light microscopic autoradiography in streptozotocin-diabetic rats, uninephrectomized rats, uninephrectomized diabetic rats, insulin-treated diabetic rats and control rats. The percentage of labelled cortical nuclei (the labelling index) was determined separately in glomeruli, proximal tubules and distal tubules after 2, 4 and 6 days on autoradiographs from 1 micron thick plastic embedded sections. The incorporation of thymidine in glomerular nuclei was consistently low (less than 1%) and no differences were found between the control and experimental groups. In both proximal and distal tubules an increase in thymidine incorporation was seen on day 2 followed by a decline on days 4 and 6. The maximal labelling on day 2 in proximal tubules was 9.1% in the uninephrectomized diabetic group, 3.7% in the diabetic group and 1.4% in the uninephrectomized group. In distal tubules the corresponding values were 5.2, 3.5 and 1.1%. The increase in kidney weight after 6 days was 83, 62 and 37%, respectively. Estimates of the net increase in the number of cortical tubular cells in the different experimental groups showed that the kidney enlargement followed different patterns with respect to the extent of cellular hyperplasia and hypertrophy. The kidney growth in uninephrectomized diabetic rats was dominated by tubular cellular hyperplasia, in the diabetic group hyperplasia and hypertrophy participated to approximately the same extent, whereas cellular hypertrophy was most pronounced in the uninephrectomized animals. Nuclear labelling in the insulin-treated diabetic rats was not different from that of control rats and consequently a hyperplastic effect of streptozotocin can be ruled out.(ABSTRACT TRUNCATED AT 250 WORDS)

Title: Relation of diabetes to mild cognitive impairment. Abstract: BACKGROUND: Type 2 diabetes mellitus is an important risk factor for Alzheimer disease and is more prevalent in elderly minority persons compared with non-Hispanic white persons. OBJECTIVE: To determine whether diabetes is related to a higher risk of mild cognitive impairment (MCI), a transitional stage between normal cognition and Alzheimer disease, in a multiethnic cohort with a high prevalence of diabetes. DESIGN: Longitudinal cohort study. SETTING: Northern Manhattan in New York, NY. PARTICIPANTS: We studied persons without prevalent MCI or dementia at baseline and with at least 1 follow-up interval. Of 1772 participants with a complete neuropsychological evaluation, 339 (19.1%) were excluded because of prevalent dementia, 304 were excluded because of prevalent MCI (17.2%), and 211 were excluded because of loss to follow-up (11.9%), resulting in a final sample of 918 participants for longitudinal analyses. MAIN OUTCOME MEASURES: We related diabetes defined by self-report to incident all-cause MCI, amnestic MCI, and nonamnestic MCI. We conducted multivariate analyses with proportional hazards regression adjusting for age, sex, years of education, ethnic group, apolipoprotein E (APOE) epsilon4 allele, hypertension, low-density lipoprotein level, current smoking, heart disease, and stroke. RESULTS: A total of 334 persons had incident MCI, 160 (47.9%) had amnestic MCI, and 174 (52.1%) had nonamnestic MCI. Diabetes was related to a significantly higher risk of all-cause MCI and amnestic MCI after adjustment for all covariates. Diabetes was also related to a higher risk of nonamnestic MCI, but this association was appreciably attenuated after adjustment for socioeconomic variables and vascular risk factors. The risk of MCI attributable to diabetes was 8.8% for the whole sample and was higher for African American persons (8.4%) and Hispanic persons (11.0%) compared with non-Hispanic white persons (4.6%), reflecting the higher prevalence of diabetes in minority populations in the United States. CONCLUSION: Diabetes is related to a higher risk of amnestic MCI in a population with a high prevalence of this disorder.

Title: Nonproliferative retinopathy in diabetes type 2. Initial stages and characterization of phenotypes. Abstract: This review addresses the initial stages of nonproliferative diabetic retinopathy in diabetes type 2. The natural history of the initial lesions occurring in the diabetic retina has particular relevance for our understanding and management of diabetic retinal disease, one of the major causes of vision loss in the western world. Diabetic retinal lesions are still reversible at this stage opening entirely new opportunities for effective intervention. Four main alterations characterize these early stages of diabetic retinopathy: microaneurysms/hemorrhages, alteration of the blood-retinal barrier, capillary closure and alterations in the neuronal and glial cells of the retina. These alterations may be monitored by red-dot counting on eye fundus images and by fluorescein leakage and retinal thickness measurements. A combination of these methods through multimodal macula mapping has contributed by identifying three different phenotypes of diabetic retinopathy. They show different types and rates of progression which suggest the involvement of different susceptibility genes. The identification of different phenotypes opens the door for genotype characterization, different management strategies targeted treatments.

Title: Residual insulin secretion in insulin dependent diabetes mellitus. Abstract: The residual insulin secretory capacity of 244 children with insulin dependent diabetes mellitus was determined by measurement of their 24 hour urinary C peptide excretion. An inverse linear relation was found between the residual B cell secretion and the duration of diabetes. The age at onset of diabetes did not affect the residual B cell function significantly.

Title: Enterovirus infection as a risk factor for beta-cell autoimmunity in a prospectively observed birth cohort: the Finnish Diabetes Prediction and Prevention Study. Abstract: Previous studies suggest that enterovirus infections may initiate and accelerate beta-cell damage years before the clinical manifestation of type 1 diabetes. We have now analyzed the role of enterovirus infections in the initiation of autoimmunity in children who have tested positive for diabetes-associated autoantibodies in a prospective study starting at birth (the Finnish Diabetes Prediction and Prevention Study). The frequency of enterovirus infections was studied using both serology and testing for the presence of enterovirus RNA in the sera of 21 children who developed and retained autoantibodies and in 104 control subjects chosen from the same study cohort and matched for the time of birth, sex, and HLA alleles determining genetic diabetes susceptibility. Sample intervals were taken as basic units of follow-up, to which the observed number of infections was adjusted. Enterovirus infections were detected in 26% of sample intervals in the case subjects and in 18% of the sample intervals in the control children (P = 0.03). A temporal relationship between enterovirus infections and the induction of autoimmunity was found; enterovirus infections were detected in 57% of the case subjects during a 6-month follow-up period preceding the first appearance of autoantibodies compared with 31% of the matched control children in the same age-group (odds ratio 3.7, 95% CI 1.2-11.4). The frequency of adenovirus infections did not differ between the patient and control groups. Our data imply that enterovirus infections are associated with the development of beta-cell autoimmunity and provide evidence for the role of enteroviruses in the initiation of beta-cell destruction.

Title: Dehydroepiandrosterone protects tissues of streptozotocin-treated rats against oxidative stress. Abstract: Chronic hyperglycemia in diabetes determines the overproduction of free radicals, and evidence is increasing that these contribute to the development of diabetic complications. It has recently been reported that dehydroepiandrosterone possesses antioxidant properties; this study evaluates whether, administered daily for three weeks per os, it may provide antioxidant protection in tissues of rats with streptozotocin-induced diabetes. Lipid peroxidation was evaluated on liver, brain and kidney homogenates from diabetic animals, measuring both steady-state concentrations of thiobarbituric acid reactive substances and fluorescent chromolipids. Hyperglycemic rats had higher thiobarbituric acid reactive substances formation and fluorescent chromolipids levels than controls. Dehydroepiandrosterone-treatment (4 mg/day for 3 weeks) protected tissues against lipid peroxidation: liver, kidney and brain homogenates from dehydroepiandrosterone-treated animals showed a significant decrease of both thiobarbituric acid reactive substances and fluorescent chromolipids formation. The effect of dehydroepiandrosterone on the cellular antioxidant defenses was also investigated, as impaired antioxidant enzyme activities were considered proof of oxygen-dependent toxicity. In kidney and liver homogenates, dehydroepiandrosterone treatment restored to near-control values the cytosolic level of reduced glutathione, as well as the enzymatic activities of superoxide-dismutase, glutathione-peroxidase, catalase. In the brain, only an increase of catalase activity was evident (p < .05), which reverted with dehydroepiandrosterone treatment. The results demonstrate that DHEA treatment clearly reduces oxidative stress products in the tissues of streptozotocin-treated rats.

Title: Characterization of N-glycosylated type I collagen in streptozotocin-induced diabetes. Abstract: The N epsilon-glycosylation of lysine and hydroxylysine residues in collagen from streptozotocin-induced-diabetic rats was confirmed and the stability of the complex shown to be due to an Amadori rearrangement. The studies also demonstrate the relative specificities of glucose, galactose and mannose in their reaction with collagen. The glycosylation of lysine in vitro occurs with glucose and galactose, but not with mannose, whereas only gucose reacts with hydroxylysine to any significant extent. Glycosylation of collagen occurs slowly during normal aging, but in contrast with reports suggesting accelerated aging of collagen in diabetic animals, we clearly demonstrated that the apparent increased stability is not due to an acceleration of the normal maturation process involving the reducible cross-links.

Title: Metoprolol improves cardiac function and modulates cardiac metabolism in the streptozotocin-diabetic rat. Abstract: The effects of diabetes on heart function may be initiated or compounded by the exaggerated reliance of the diabetic heart on fatty acids and ketones as metabolic fuels. beta-Blocking agents such as metoprolol have been proposed to inhibit fatty acid oxidation. We hypothesized that metoprolol would improve cardiac function by inhibiting fatty acid oxidation and promoting a compensatory increase in glucose utilization. We measured ex vivo cardiac function and substrate utilization after chronic metoprolol treatment and acute metoprolol perfusion. Chronic metoprolol treatment attenuated the development of cardiac dysfunction in streptozotocin (STZ)-diabetic rats. After chronic treatment with metoprolol, palmitate oxidation was increased in control hearts but decreased in diabetic hearts without affecting myocardial energetics. Acute treatment with metoprolol during heart perfusions led to reduced rates of palmitate oxidation, stimulation of glucose oxidation, and increased tissue ATP levels. Metoprolol lowered malonyl-CoA levels in control hearts only, but no changes in acetyl-CoA carboxylase phosphorylation or AMP-activated protein kinase activity were observed. Both acute metoprolol perfusion and chronic in vivo metoprolol treatment led to decreased maximum activity and decreased sensitivity of carnitine palmitoyltransferase I to malonyl-CoA. Metoprolol also increased sarco(endo)plasmic reticulum Ca(2+)-ATPase expression and prevented the reexpression of atrial natriuretic peptide in diabetic hearts. These data demonstrate that metoprolol ameliorates diabetic cardiomyopathy and inhibits fatty acid oxidation in streptozotocin-induced diabetes. Since malonyl-CoA levels are not increased, the reduction in total carnitine palmitoyltransferase I activity is the most likely factor to explain the decrease in fatty acid oxidation. The metabolism changes occur in parallel with changes in gene expression.

Title: Diabetes decreases Na+-K+ pump concentration in skeletal muscles, heart ventricular muscle, and peripheral nerves of rat. Abstract: Na+-K+-ATPase or the Na+-K+ pump is essential for some specific properties of muscle and nerve tissue such as contractility and excitability. Previous studies have shown conflicting variations in Na+-K+-ATPase activity or Na+-K+ pump concentration of muscle cells in experimental diabetes. Our study demonstrates that early untreated diabetes in rats induced by injection of streptozocin is associated with decreases in [3H]ouabain binding-site concentration of 24-48% in various skeletal muscles and 16% in peripheral nerves as well as a decrease in K+-dependent 3-O-methylfluorescein phosphatase activity of 21% in the heart ventricle. These effects could be prevented by insulin treatment. They probably represent a decrease in the concentration of Na+-K+ pumps. There was no evidence for more than one population of Na+-K+ pumps in intact samples of skeletal muscle and nerves from normal, diabetic, and insulin-treated animals. The decrease in Na+-K+ pump concentration in nerve cells may be due to atrophy of the axons. In skeletal muscles, myocardium, and peripheral nerves, the observed decrease in Na+-K+ pump concentration may be important for the pathophysiology of diabetes. We emphasize that quantification of Na+-K+-ATPase or the Na+-K+ pump in muscle and nerve tissue from diabetic animals should preferably be performed with either intact samples or crude homogenates of whole tissue.

Title: Susceptibility to insulin-dependent diabetes defined by restriction enzyme polymorphism of HLA-D region genomic DNA. Abstract: DNA fragments complementary to cloned sequences encoding HLA-D region class II antigen alpha- and beta-chains were determined by genomic blotting with DNA from HLA-typed members of 22 complete families, 12 of which had a proband with insulin-dependent diabetes mellitus (IDDM). Analysis of genotypes showed that the DNA sequences were linked to HLA-DR and permitted confirmation of recombinations in two families. Digestion with the restriction enzymes BamHI, EcoRI, and PstI and hybridization with an HLA-D region beta-chain cDNA probe confirmed a BamHI 3.7 kilobase (kb) fragment present at low frequency among diabetic individuals and a BamHI 3.2 kb fragment that was also decreased among the diabetic subjects compared with siblings (P less than 0.05) as well as nonrelated control siblings (P less than 0.02) and their parents (P less than 0.01). BamHI 12.0 kb (P less than 0.05) and 5.8 kb (P less than 0.02, P less than 0.02), EcoRI 20 kb (P less than 0.05, P less than 0.02), and PstI 6.0 kb (P less than 0.05) fragments were more frequent in diabetic individuals compared with nonrelated control siblings or their parents, respectively. Analysis of individual haplotypes revealed that HLA-DR4-containing chromosomes were heterogeneous among controls but that the diabetic individuals showed a similar pattern of restriction fragment length polymorphism. Genomic blotting of blood lymphocyte DNA with a cDNA clone encoding the chain of HLA-D region class II antigens permits detection of fragments that are strongly associated with IDDM.