bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of short-term dietary weight loss on cortisol secretion and metabolism in obese men
Authors: Johnstone AM , Faber P , Andrew R , Gibney ER , Elia M , Lobley G , Stubbs RJ , Walker BR
Published: January 2005

OBJECTIVES: Obesity is associated with increased inactivation of cortisol by hepatic A-ring 5alpha- and 5beta-reductases, impaired hepatic regeneration of cortisol from cortisone by 11beta-hydroxysteroid dehydrogenase type 1 (11HSD1), but increased subcutaneous adipose 11HSD1 activity enhancing local cortisol levels in fat. Cause and effect between obesity and abnormal cortisol metabolism is untested. DESIGN: Acute weight loss was induced by very low calorie diet (VLCD) or starvation in obese men. METHODS: Otherwise healthy males (aged 20-55 years; body mass index (BMI) 30-40 kg/m2) were studied after 6 days on a weight maintenance diet; then after either 6 days of starvation (n=6) or 3 weeks of VLCD (2.55 MJ; n=6); then after 1 week of weight maintenance; and finally after 2 weeks of being allowed to feed ad libitum. Plasma samples were obtained from indwelling cannulae at 0930 h and 1815 h and a 24 h urine collection was completed for analysis of cortisol metabolites by gas chromatography/mass spectrometry. RESULTS: Data are mean+/-S.E.M. BMI fell (kg/m3) from 34.8+/-0.8 at baseline to 31.8+/-1.4 on VLCD and 32.7+/-1.1 on starvation. Starvation caused a rise in plasma cortisol (at 0930 h from 143+/-17 to 216+/-11 nM, P<0.001) but no change in total urinary cortisol metabolites. VLCD did not alter plasma cortisol and markedly reduced cortisol metabolite excretion (from 15.8+/-1.1 mg/day at baseline to 7.0+/-1.1 mg/day, P<0.001). Relative excretion of 5alpha-reduced cortisol metabolites fell on both diets, but there were no changes in cortisol/cortisone metabolite ratios reflecting 11HSD activities. CONCLUSIONS: Weight loss with VLCD in obesity reverses up-regulation of hepatic A-ring reductases and normalises cortisol production rate; in contrast, starvation produces acute stress and further activation of cortisol secretion. We suggest that activation of cortisol secretion is not an irreversible intrinsic abnormality in obese patients, and speculate that dietary content has an important influence on the neuroendocrine response to weight loss.
Body weight and glucose metabolism have a different effect on circulating levels of ICAM-1, E-selectin, and endothelin-1 in humans
Authors: Pontiroli AE , Pizzocri P , Koprivec D , Vedani P , Marchi M , Arcelloni C , Paroni R , Esposito K , Giugliano D
Published: January 2005

BACKGROUND: Endothelial dysfunction and inflammation are present in both type 2 diabetes mellitus (T2DM) and obesity. In this paper we compared the role of weight loss and of glycaemic control in determining circulating levels of ICAM-1, endothelin-1 (ET-1), and E-selectin in patients with morbid (grade 3) obesity. METHODS AND RESULTS: ICAM-1, E-selectin, and ET-1 were higher in obese patients (n=96) than in lean controls (n=30); among obese patients, the three molecules were higher in T2DM patients (n=26) than in patients with normal (NGT, n=43) or impaired (IGT, n=27) glucose tolerance. Sixty-eight obese patients had a significant weight loss induced by bariatric surgery, and showed a significant decrease in blood glucose, HbA1c and all molecules, so that ICAM-1, E-selectin, and ET-1 were not different in NGT, IGT and T2DM patients, and in lean controls; in 13 patients with a small weight loss induced by diet, changes were not significant, in spite of a significant reduction in blood glucose and HbA1c. At stepwise regression, changes in ICAM-1, ET-1, and E-selectin significantly correlated only with change in body mass index. CONCLUSIONS: These data indicate that weight loss is more important than glycaemic control in regulating circulating levels of ICAM-1, ET-1, E-selectin in morbidly obese subjects.
Adiponectin is independently associated with glycosylated haemoglobin
Authors: Fernandez-Real JM , Botas-Cervero P , Lopez-Bermano A , Casamitjana R , Funahashi T , Delgado E , Kihara S , Ricart W
Published: January 2005

BACKGROUND: In humans, adiponectin has been demonstrated to circulate in inverse proportion to the degree of insulin resistance. OBJECTIVE: To investigate the association between adiponectin and glycosylated haemoglobin (HbA1c) in a population-based study. DESIGN AND METHODS: Two hundred and ninety-seven individuals aged 30-75 years were enrolled in a cross-sectional study. They included patients with type 2 (non-insulin-dependent) diabetes mellitus and stable, good metabolic control (n=32) and individuals with glucose intolerance (n=54). Adiponectin was measured using a sandwich enzyme-linked immunosorbent assay (intra-assay and interassay coefficients of variation 3.3 and 7.4% respectively). RESULTS: Adiponectin correlated with age (r=0.161; P=0.006), body mass index (r=-0.197; P=0.001), diastolic blood pressure (r=-0.181; P=0.005), fasting glucose and HbA1c (r=-0.251 and r=-0.22 respectively; P<0.0001), high-density lipoprotein cholesterol (r=0.442; P<0.001) and serum triglycerides (r=-362; P<0.001). In multiple regression analysis, sex, age, fasting and post-load glucose, and adiponectin independently contributed to 40% of the variance in HbA1c. Among individuals with normal glucose tolerance, fasting glucose (P=0.0033), post-load glucose (P=0.0015), age (P=0.001) and adiponectin (P=0.0083) independently contributed to 21% of the variance in HbA1c. CONCLUSION: Adiponectin is significantly associated with altered glucose metabolism and independently contributes to the variance of HbA1c in a population-based manner.
Evidence of increased visceral obesity and reduced physical fitness in healthy insulin-resistant first-degree relatives of type 2 diabetic patients
Authors: Nyholm B , Nielsen MF , Kristensen K , Nielsen S , Ostergard T , Pedersen SB , Christiansen T , Richelsen B , Jensen MD , Schmitz O
Published: January 2005

OBJECTIVE: First-degree relatives (FDR) of type 2 diabetic patients are often insulin resistant. Visceral obesity is closely linked to both insulin resistance and type 2 diabetes. We therefore hypothesized that the inheritance of an increased tendency to store fat in visceral fat depots may be a characteristic phenotypic feature in FDR contributing to their insulin resistance. DESIGN AND METHODS: We measured fat distribution in 20 FDR and 14 age-, gender- and body mass index (BMI)-matched controls employing dual energy X-ray absorbtiometry (DEXA)- and computed tomography (CT)-scanning. Insulin-stimulated glucose uptake (ISGU) was determined by a hyperinsulinemic clamp and maximal aerobic work capacity (VO2 max) by a bicycle ergometer test. Baseline lipolysis was measured using [3H]palmitate. The activity level of the hypothalamic-pituitary-adrenal axis was assessed as the 24 h urinary (u)-cortisol/creatinine ratio. RESULTS: All subjects had a normal oral glucose tolerance test (OGTT), but FDR were insulin resistant (ISGU: 6.64+/-0.48 vs 9.12+/-0.98 mg/kg ffm/min, P=0.01). Despite similar BMI (25.2+/-0.5 vs 24.8+/-0.7 kg/m2, P=0.61) and overall fat mass (26.4+/-1.6 vs 24.2+/-2.1%, P=0.41) in FDR vs controls, the amount of visceral adipose tissue was substantially increased (65.9+/-10.0 vs 40.1+/-11.3 cm2, P<0.05) and VO2 max was reduced (52.2+/-3.1 vs 63.3+/-3.9 ml/kg ffm/min, P<0.05) in FDR. Visceral adiposity was inversely correlated with ISGU (FDR: r=-0.52, P<0.05; controls: r=-0.65, P<0.01) and in multiple regression analysis visceral adiposity (P<0.01), VO2 max (P<0.001) and a family history of type 2 diabetes (P<0.05) (r2=0.64) all significantly and independently contributed to the level of ISGU. Baseline palmitate appearance (145+/-10 vs 139+/-15 micromol/min, P=0.74) and the 24 h u-cortisol/creatinine ratio ((24.9+/-1.3 vs 27.4+/-2.0).10(-6), P=0.28) were both comparable in the two groups. CONCLUSION: Healthy but insulin-resistant FDR have enhanced visceral obesity and reduced VO2 max compared with people without a family history of diabetes, despite similar BMI and overall fat mass. Both the visceral adiposity and reduced aerobic fitness are strongly associated with and may contribute to their insulin resistance.
Metabolic and endocrine effects of treatment with peroral or transdermal oestrogens in conjunction with peroral cyproterone acetate in women with polycystic ovary syndrome
Authors: Vrbikova J , Stanicka S , Dvorakova K , Hill M , Vondra K , Bendlova B , Starka L
Published: January 2005

OBJECTIVE: To compare the influence of transdermal and peroral oestrogen treatments in conjunction with cyproterone acetate (CPA) on metabolic and hormonal parameters in women with polycystic ovary syndrome (PCOS). PATIENTS AND METHODS: Twenty-four women with PCOS, aged 25.4+/-4.3 (mean+/-s.d.) years, body mass index 24.5+/-3.9 kg/m2 were randomly assigned to receive either transdermal oestradiol plus CPA (n=12) or a peroral oestradiol-CPA combination (n=12). Before and after 3 months of treatment, basal blood samples, euglycaemic hyperinsulinaemic clamp combined with indirect calorimetry and arginine tests were performed. ANOVA and Student's t-test or Wilcoxon's test were used for statistical analyses. RESULTS: After peroral oestradiol-CPA, insulin sensitivity (P<0.004) and the disposition index as the function of insulin sensitivity and secretion (P<0.0001) decreased significantly. Fasting insulin (P<0.05), cholesterol (P<0.05), high-density lipoprotein cholesterol (P<0.05) and sex-hormone binding globulin (P<0.0001) increased significantly. Dehydroepiandrosterone (P<0.05) and 17-OH progesterone (P<0.01) decreased significantly. After transdermal oestradiol+CPA, no significant changes were observed in sex-hormone binding globulin and androgen concentrations, insulin sensitivity or disposition index. CONCLUSIONS: In women with PCOS, peroral oestrogens (at doses common in combined oral contraceptives) led to a significant impairment in insulin secretion and action. In contrast, the transdermal application of oestrogens did not significantly influence insulin sensitivity.
The role of CXCR5 and its ligand CXCL13 in the compartmentalization of lymphocytes in thyroids affected by autoimmune thyroid diseases
Authors: Aust G , Sittig D , Becherer L , Anderegg U , Schutz A , Lamesch P , Schmucking E
Published: January 2005

OBJECTIVE: Graves' disease (GD) and Hashimoto's thyroiditis (HT) are characterized by lymphocytic infiltrates partly resembling secondary lymphoid follicles in the thyroid. CXCR5 and its ligand CXCL13 regulate compartmentalization of B- and T-cells in secondary lymphoid organs. The aim of the study was to elucidate the role of this chemokine receptor-ligand pair in thyroid autoimmunity. METHODS: Peripheral blood and thyroid-derived lymphocyte subpopulations were examined by flow cytometry for CXCR5. CXCR5 and CXCL13 cDNA were quantified in thyroid tissues by real-time RT-PCR. RESULTS: We found no differences between the percentages of peripheral blood CXCR5+ T- and B-cells in GD patients (n=10) and healthy controls (n=10). In GD patients, the number of memory CD4+ cells expressing CXCR5 which are functionally characterized as follicular B helper T-cells is higher in thyroid-derived (18+/-3%) compared with peripheral blood T-lymphocytes (8+/-2%). The highest CXCL13 mRNA levels were found in HT (n=2, 86.1+/-1.2 zmol (10(-21) mol) cDNA/PCR) followed by GD tissues (n=16, 9.6+/-3.5). Only low amounts were determined in thyroid autonomy (TA) (n=11) thyroid tissues, irrespective of whether the autonomous nodule (0.5+/-0.1) or the surrounding normal tissue (1.8+/-0.7) had been analyzed. The same differences were found for CXCR5 (HT: 179.1+/-6.8; GD: 17.4+/-10.6; TA(nodule): 0.8+/-0.5; TA(normal): 4.4+/-3.6). In GD, there is a correlation between CXCL13 and CXCR5 mRNA levels and the number of focal lymphocytic infiltrates and germinal centers as well as anti-thyroperoxidase but not anti-TSH receptor autoantibodies. CONCLUSIONS: CXCR5 and CXCL13 play an essential role in maintaining B- and T-cells in lymphocytic infiltrates and ectopic follicles in thyroid tissue from patients affected by autoimmunity.
Effect of GHRH and GHRP-2 treatment in vitro on GH secretion and levels of GH, pituitary transcription factor-1, GHRH-receptor, GH-secretagogue-receptor and somatostatin receptor mRNAs in ovine pituitary cells
Authors: Yan M , Hernandez M , Xu R , Chen C
Published: January 2005

OBJECTIVE: Growth hormone (GH)-releasing hormone (GHRH) and GH-releasing peptides (GHRPs) stimulate the release of GH through their specific receptors on somatotropes. Combined GHRH and GHRP administration causes a synergistic GH release in vivo by an unknown mechanism. The current study focuses on the direct action of GHRH and GHRP on several molecular targets in somatotropes. DESIGN AND METHODS: To clarify the mechanism of action, ovine somatotropes were used to measure the expression of mRNAs encoding for GH, pituitary transcription factor-1 (Pit-1), GH-secretagogue receptor (GHS-R), GHRH-R, somatostatin receptor subtypes (sst-1 and sst-2) and GH release after GHRH and GHRP-2 treatment for 0.5, 1, 1.5 and 2 h. RESULTS: GHRH (10 nM), GHRP-2 (100 nM) and combined GHRH-GHRP-2 increased the levels of GH mRNA and GH release from 0.5 to 2 h in a time-dependent manner. The levels of Pit-1, GHRH-R and GHS-R mRNA were increased after 0.5 h treatment of cells with GHRH and GHRP-2. The levels of sst-1 but not sst-2 mRNA were significantly increased after 0.5 and 1 h of GHRH treatment. In contrast, both sst-1 and sst-2 mRNA expression was inhibited after 0.5-2 h of GHRP treatment. CONCLUSIONS: These data demonstrate a direct in vitro modification of ovine somatotropes by GHRH and GHRP-2 resulting in altered GHRH-R, GHS-R, Pit-1, sst-1, sst-2 and GH gene expression; this may underlie the regulatory action of GHRH and GHRP-2 on GH secretion.
Insights into the molecular biology of the estrogen receptor define novel therapeutic targets for breast cancer
Authors: Hanstein B , Djahansouzi S , Dall P , Beckmann MW , Bender HG
Published: January 2005

Evidence for a role of ovarian factors in the growth of metastatic breast cancer was first recognized over 100 years ago. Today, anti-estrogens are central to the treatment of breast cancer of all stages. We now understand that the action of estrogen is mediated by the estrogen receptors (ER) which are members of the nuclear receptor family of ligand-regulated transcription factors. In this article we review the molecular mechanisms through which ER activates transcription of target genes and through which available anti-estrogens mediate their therapeutic effects. We discuss possible mechanisms of failure of treatment with current anti-estrogens and how newer anti-estrogens under development attempt to address these problems. In addition an expanded view of the molecular mechanisms of estrogen action is leading to the development of novel selective ER modulators or SERMs.
Prolonged jaundice and hypothyroidism as the presenting symptoms in a neonate with a novel Prop1 gene mutation (Q83X)
Authors: Voutetakis A , Maniati-Christidi M , Kanaka-Gantenbein C , Dracopoulou M , Argyropoulou M , Livadas S , Dacou-Voutetakis C , Sertedaki A
Published: January 2005

OBJECTIVE: To identify the genetic defect in a neonate presented with prolonged jaundice and central hypothyroidism. DESIGN: Central hypothyroidism was detected in a neonate initially examined for prolonged jaundice, and levothyroxine therapy was initiated. Direct sequencing of the Prop1 gene was carried out and pituitary function and morphology were evaluated using hormonal testing and magnetic resonance imaging (MRI) respectively. METHODS: Dynamic hormonal testing was carried out using established methodologies. Hormones were determined by RIA or chemiluminescence immunoassays. Genomic analysis of the Prop1 gene was performed by direct sequencing. MRI protocol: sagittal spin echo T2-weighted scans 2500/90 (TR/TE), plain and contrast-enhanced sagittal and coronal spin echo T1-weighted scans 500/20 (TR/TE). RESULTS: Low thyroid hormones (coupled with lack of TSH rise), low GH, normal cortisol and normal prolactin values were detected. Direct sequencing revealed the presence of two mutations in the Prop1 gene: GA296del and Q83X. The Q83X was further confirmed by PvuII restriction digestion and represented a novel Prop1 gene mutation, which was not detected in 100 controls tested. Pituitary enlargement was detected, with respect to normal-for-age controls. CONCLUSIONS: (i) The Q83X mutation extends the spectrum of Prop1 gene mutations; (ii) central hypothyroidism in a neonate might constitute the initial sign of Prop1 gene defect; (iii) the patient is the youngest individual with Prop1 gene defect and pituitary enlargement presented to date; and (iv) early detection of Prop1 gene mutations facilitates genetic counseling and ensures prompt management of the anticipated hormonal insufficiencies.
Potent thyrotrophin receptor-blocking antibodies: a cause of transient congenital hypothyroidism and delayed thyroid development
Authors: Evans C , Jordan NJ , Owens G , Bradley D , Ludgate M , John R
Published: January 2005

OBJECTIVE: We describe an infant with surprisingly severe neonatal hypothyroidism due to transplacental passage of thyrotrophin receptor (TSH-R)-blocking antibodies (TBAb). DESIGN AND METHODS: TBAb were detected using a cell line which stably expresses the human TSH-R and a cAMP-responsive luciferase reporter by their ability to inhibit TSH-stimulated luciferase expression. Potent TBAb were detected in maternal serum and initially in the infant's serum but, in the latter, TBAb decreased over time to within the reference range by 3-4 months of age, illustrating the transient nature of this condition. RESULTS: The thyroid function of this child did not return to normal on withdrawal of thyroxine therapy at 16 months of age when he developed transient compensated hypothyroidism. CONCLUSIONS: We propose that the presence of potent TBAb in utero and in the first weeks of life may have implications for the development of a normally sized thyroid gland. We have demonstrated the presence of TBAb in the mother's milk and, as far as we are aware, this is the first such report. However, the TBAb in the milk probably did not contribute significantly to hypothyroidism in the child, given the reducing antibody titre in his circulation.
Decreased expression of thyrotropin receptor gene suggests a high-risk subgroup for oncocytic adenoma
Authors: Mirebeau-Prunier D , Guyetant S , Rodien P , Franc B , Baris O , Rohmer V , Reynier P , Tourmen Y , Malthiery Y , Savagner F
Published: January 2005

OBJECTIVE: The malignancy of thyroid oncocytic tumours, or oncocytomas, is higher than that of follicular tumours. The aim of this study was to investigate the role of thyroid-specific genes in oncocytic tumours and papillary carcinomas. DESIGN AND METHODS: We compared 29 oncocytic tumours with 12 papillary carcinomas. Real-time quantitative PCR was used to measure the expression of thyroid-specific differentiation markers (thyrotrophin-stimulation hormone receptor (TSHR), thyroglobulin (TG) and Na(+)/I(-) symporter (NIS)), transcription factors (thyroid transcription factor-1 (TTF-1) and paired box gene-8 (PAX8)) and nuclear receptors (peroxisome proliferator-activated receptor (PPARgamma1) and thyroid hormone receptor (TRbeta1)) involved in thyroid carcinogenesis. RESULTS: TSHR, TTF-1 and TRbeta1 levels were significantly lower in oncocytic tumours than in papillary carcinomas, as a result of specific biological changes in oncocytic tumours. However, PAX8 and PPARgamma1 did not seem to be involved in the process. Applying the criterion of the underexpression of the thyroid-specific differentiation markers, TSHR, TG and NIS, we classified the oncocytic tumours and papillary carcinomas into three groups. In the first, all three markers were underexpressed; in the second, TSHR was normal while TG and NIS were underexpressed; and in the third, only NIS was underexpressed. The expression patterns revealed that 13 of the 24 oncocytic adenomas underexpressing TSHR in our study, as did four of the five oncocytic carcinomas. CONCLUSION: Cases of oncocytic adenoma associated with low levels of TSHR could be putative oncocytic carcinomas and should therefore receive adequate follow-up [corrected].
Diagnostic management of suspected metastatic thyroid carcinoma: clinical value of octreotide scintigraphy in patients with negative high-dose radioiodine scans
Authors: Giammarile F , Houzard C , Bournaud C , Hafdi Z , Sassolas G , Borson-Chazot F
Published: January 2005

OBJECTIVES: Somatostatin receptor scintigraphy (SRS) with (111)In-octreotide has been suggested as a potential tool for the detection of recurrent or metastatic differentiated thyroid cancer when no radioiodine uptake can be demonstrated in tumour sites. However, there is no consensus concerning the performance and clinical impact of this examination in such instances. DESIGN AND METHODS: A prospective study was undertaken to evaluate SRS in 43 patients (18 men, 25 women) with papillary (n=20), follicular (n=9), insular (n=6) and oncocytic (n=8) thyroid carcinomas with elevated serum thyroglobulin (Tg) levels and no detected radioiodine uptake. RESULTS: Evaluation criteria were interpreted in terms of an assumed presence of tumoural tissue. Sensitivity of SRS was 51%, clearly lower than that of conventional imaging procedures, and of positron emission tomography using [(18)F]-2-fluoro-2-deoxy-d-glucose, performed in a subset of 27 patients. In addition, we observed two false-positive foci of uptake of octreotide that corresponded to inflammatory pulmonary sites. The sensitivity was higher in patients with Tg levels greater than 50 microg/l (76%) for detecting mediastinal lesions (93%), and in patients with oncocytic cancer (88%). Finally, SRS changed treatment strategy in four patients. CONCLUSION: In differentiated thyroid cancer, SRS is a moderately sensitive method for the detection of lesions unable to concentrate iodine and appears useful only in patients with very high Tg levels or in oncocytic cancer.
Compliance with follow-up and the informative value of diagnostic whole-body scan in patients with differentiated thyroid carcinoma given recombinant human TSH
Authors: Cohen O , Dabhi S , Karasik A , Zila Zwas S
Published: January 2005

OBJECTIVE: Protocols for monitoring patients with differentiated thyroid cancer (DTC) include measurement of serum Tg and, for most patients, whole-body scan (WBS) with low radioiodine activities ('diagnostic' WBS). Recently, recombinant human thyroid-stimulating hormone (rhTSH) has become available to provide the TSH stimulation necessary for these procedures, whilst avoiding thyroid hormone withdrawal and hypothyroid complications. In addition, the inclusion of diagnostic WBS in DTC follow-up has recently become controversial. We have assessed the compliance with withdrawal-aided monitoring and the informative value of diagnostic WBS in consecutive tertiary referral center patients. DESIGN: Forty-eight patients received rhTSH (0.9 mg) in two consecutive daily injections, with radioiodine administration 24 h, diagnostic WBS 48 h, and serum Tg testing prior to and 72 h later. METHODS: Compliance with withdrawal-aided monitoring was assessed with a questionnaire provided by the referring physician, patient record analysis, and patient interview. The informative value of diagnostic WBS was assessed by comparing findings against serum Tg measurements in light of physical and other radiological examinations. RESULTS: Forty of the forty-eight patients were female, the mean age was 43.9 years and the median follow-up from diagnosis was 4.5 years (range 1-19 years). Twenty-seven (56%) patients were compliant and 12 (25%) were non-compliant; compliance was not known in nine. Of 17 patients with clinically suspicious or significant findings on any available modality, four had uptake outside the thyroid bed on WBS but stimulated Tg <2.5 ng/ml on immunometric assay, while five had a negative WBS with serum Tg >2.5 ng/ml. CONCLUSIONS: Thyroid hormone withdrawal substantially impairs, and rhTSH administration substantially promotes, compliance with DTC monitoring. rhTSH-aided WBS is informative and should be included in the follow-up of unselected patients with DTC.
Effect of short-term treatment with low dosages of the proton-pump inhibitor omeprazole on serum chromogranin A levels in man
Authors: Giusti M , Sidoti M , Augeri C , Rabitti C , Minuto F
Published: January 2005

BACKGROUND: Measurement of chromogranin A (CgA) levels in blood can be used to monitor neuroendocrine tumors (NETs). CgA levels may also be elevated in several other endocrine and non-endocrine diseases. It is well known that drugs affecting acid gastric secretion can increase gastrin. Proton-pump inhibitors are extensively used but only a few data have been reported on their effects on CgA secretion. DESIGN: The aim of the study was to evaluate the short-term effect of low dosages of omeprazole (OM) on CgA levels and to sensitize endocrinologists to possible false positive values of CgA in order to prevent expensive diagnostic work-up in searching for NETs. SUBJECTS AND METHODS: Thirty-five female and nine male in-patients (18-81 years) were studied. Mild or severe hypertension in 20 patients needed therapy. Endocrine and metabolic diseases were diagnosed in the majority of patients. CgA levels were evaluated before and during OM therapy (10 mg/day, orally). RESULTS: Without OM therapy, CgA levels were 64+/-6 microg/l. Elevated baseline CgA levels were found in nine subjects. CgA levels were significantly related to age (P<0.001), creatinine levels (P=0.03) and the severity of hypertension (P=0.002). On short-term OM therapy (n=42; 18.8+/-2.4 days; range 5-90 days) a significant (P<0.001) increase in CgA (145+/-22 microg/l) from baseline (63+/-7 microg/l) levels was found. The average net CgA increase on short-term OM therapy was 93+/-20 microg/l. There was a significant correlation between baseline CgA levels and CgA increase on short-term OM therapy (P=0.004) but not between the increase in CgA and the duration of the therapy. CONCLUSIONS: An increase in CgA levels quickly follows the start of low dosages of OM. This release is more pronounced when the baseline CgA levels are already increased by slight renal insufficiency or severe hypertension. In this common clinical situation an intensive work-up for NETs is not justified before reassessment of CgA after the withdrawal of OM.
Circulating levels of receptor activator of nuclear factor-kappaB ligand/osteoprotegerin/macrophage-colony stimulating factor in a presumably healthy human population
Authors: Trofimov S , Pantsulaia Ia , Kobyliansky E , Livshits G
Published: January 2005

OBJECTIVES: To determine the ranges of variation of circulating receptor activator of nuclear factor-kappaB ligand (RANKL)/osteoprotegerin (OPG)/macrophage-colony stimulating factor(M-CSF) and to ascertain their potential relationships with age, sex and menopausal status in women, and with sex hormones in a population-based healthy cohort. SUBJECTS AND METHODS: Blood samples were collected with EDTA after an overnight fast. The plasma levels of each of the above biochemical indices were measured by ELISA in a total of 566 apparently healthy individuals aged 18-75 years. RESULTS: The plasma concentrations of cytokine molecules in the entire sample ranged from 674 to 4929 pg/ml for OPG, from 105 to 4468 pg/ml for soluble RANKL (sRANKL), and from 187 to 7604 pg/ml for M-CSF. The OPG levels demonstrated a clear positive correlation with age in both sexes (r=0.42 and 0.43, P<0.001, for men and women respectively). Application of the two-interval mathematical model revealed that in females OPG levels were age-independent until age 42, but then showed clear and significant correlation with age (r=0.48, P<0.001). As a result, young females (before 42 years) had a substantially lower average OPG level, 1377.8+/-327.68 pg/ml, in comparison with older women, 1666.02+/-397.14 pg/ml. The M-CSF correlation with age was significantly greater in women (r=0.29, P<0.001) compared with men (r=0.17, P<0.01). Significant negative correlations between plasma levels of both OPG and M-CSF with estradiol concentrations were observed in women (r=-0.39, P<0.01; r=-0.25, P<0.001 respectively). sRANKL did not correlate with either age or sex hormones in either women or men. CONCLUSION: Age and sex affect differently the interindividual variation of OPG, RANKL and M-CSF. Our observations could form the basis for further research to establish provisional reference limits for OPG and RANKL, which are potential markers for benign and malignant processes in bone.
Autoantibodies to human tryptophan hydroxylase and aromatic L-amino acid decarboxylase
Authors: Dal Pra C , Chen S , Betterle C , Zanchetta R , McGrath V , Furmaniak J , Rees Smith B
Published: January 2005

OBJECTIVE: To assess the prevalence of autoantibodies (Abs) to tryptophan hydroxylase (TPH) and aromatic l-amino acid decarboxylase (AADC) in patients with different autoimmune diseases and to analyse their respective epitopes. DESIGN: TPH and AADC Abs were measured in an immunoprecipitation assay using (35)S-labelled full-length and fragments of TPH and AADC. METHODS: Patients with different autoimmune adrenal diseases (n=84), non-adrenal autoimmune diseases (n=37), idiopathic vitiligo (n=8) and 56 healthy blood donors were studied. RESULTS: Fourteen of twenty-three (61%) of patients with autoimmune polyglandular syndrome (APS) type I and 1/34 (3%) of patients with isolated Addison's disease (AD) were positive for TPH Abs. None of the patients with APS type II (n=27), coeliac disease (n=10), autoimmune thyroid disease (AITD) (n=11), type 1 diabetes mellitus (DM) (n=16) or idiopathic vitiligo (n=8) was positive for TPH Abs. AADC Abs were detected in 12/23 (52%) patients with APS type I, in 1/29 (3%) patients with APS type II and 1/34 (3%) patients with isolated AD. None of the patients with coeliac disease, type 1 DM, AITD or idiopathic vitiligo was positive for AADC Abs. TPH Abs were found to interact with the C-terminal amino acids (aa) 308-423, central aa 164-205 and N-terminal aa 1-105 of the TPH molecule. AADC Ab binding epitopes were within the C-terminal aa 382-483, the central aa 243-381 and the N-terminal aa 1-167. CONCLUSIONS: Our study suggests that TPH Abs and AADC Abs react with several different epitopes and that different epitopes are recognized by different sera. The prevalence of TPH Abs and AADC Abs in patients with APS type I in our study is in agreement with previous reports. TPH Abs and AADC Abs were found very rarely in patients with other forms of autoimmune adrenal disease and were not detected in patients with non-adrenal autoimmune diseases.
Diagnosis of primary aldosteronism: value of different screening parameters and influence of antihypertensive medication
Authors: Seiler L , Rump LC , Schulte-Monting J , Slawik M , Borm K , Pavenstadt H , Beuschlein F , Reincke M
Published: January 2005

OBJECTIVE: The aim of this study was to investigate the utility of different screening techniques for primary aldosteronism (PA), including serum aldosterone (SA), plasma renin activity (PRA) and the SA/PRA ratio in hypertensive patients of a tertiary-care centre. Furthermore, the influence of antihypertensive medication on SA and the SA/PRA ratio were studied. DESIGN: Clinical records of 425 hypertensive patients who had SA and PRA measurements over a 27-month period were analysed retrospectively. Eighty patients were excluded from further analysis because of incomplete data. The remaining 345 patients were classified into the following groups: patients with essential hypertension (EH) (n=260, 75.4%), patients with PA (n=49, 14.2%) and patients with secondary hypertension other than PA (n=36, 10.4%). Diagnosis of PA was made in accordance with established laboratory criteria (including measurements of SA, PRA, urinary excretion of aldosterone and metabolites, imaging techniques and response to treatment). RESULTS: Although mean serum potassium values were significantly lower (P<0.001) in the PA group compared with the EH group, 61% of PA subjects were normokalaemic (3.4-5.2 mmol/l). The SA/PRA ratio alone identified 94% of the patients with PA, but was false positive in 30% of the patients with EH. The SA/PRA ratio together with SA>150 g/ml increased the diagnostic accuracy, led to the correct identification of 84% of the patients with PA, and decreased the false-positive rate to 3%. A multivariate binary logistic regression analysis based on SA and PRA was performed, which identified PA with 90% sensitivity and 91% accuracy. The SA(2)/PRA or the SA(3)/PRA ratio was found useful for simplification of the regression analysis. Antihypertensive medication influenced SA, PRA and the SA/PRA ratio only in EH patients. In EH patients taking beta-adrenoceptor antagonists PRA tended to be lower, leading to a significantly higher SA/PRA ratio and therefore increasing the false-negative rate. CONCLUSION: To reduce false-positive results in screening for PA, and thereby avoid unnecessary and cost-intensive diagnostic procedures, SA should be taken into account in addition to the SA/PRA ratio as a second screening criterion. Alternatively, the SA(2)/PRA or the SA(3)/PRA ratio is more accurate screening tests than the SA/PRA ratio. Beta-blockers should be avoided whilst screening for PA.
Effect of glucocorticoids on adiponectin: a study in healthy subjects and in Cushing's syndrome
Authors: Fallo F , Scarda A , Sonino N , Paoletta A , Boscaro M , Pagano C , Federspil G , Vettor R
Published: January 2005

OBJECTIVE: Glucocorticoids were found to inhibit adiponectin gene expression and secretion both in vitro and in animal models. We evaluated first the acute effect of i.v. glucocorticoids on adiponectin in normal subjects and secondly plasma adiponectin levels in a series of patients with Cushing's syndrome compared with controls. DESIGN AND METHODS: Hydrocortisone (25 mg) was administered i.v. to five healthy volunteers, with blood samples taken at -15, 0, 30, 60, 120 and 180 min. Twenty-one patients with Cushing's syndrome were divided in two groups: one with 11 obese and the other with 10 non-obese Cushing's patients. Each group was compared with controls that were matched for sex, age, body mass index, waist circumference, glucose, insulin, lipid levels and blood pressure. RESULTS: In normal subjects, hydrocortisone produced a decrease in adiponectin at 30 and 60 min, compared with placebo (P<0.05). Adiponectin was lower in non-obese Cushing's patients than in non-obese controls (P<0.004). In contrast, there was no difference in adiponectin levels in obese Cushing's patients and in obese controls. Adiponectin was inversely correlated (P<0.05) with homeostasis model assessment index in both obese and non-obese Cushing's patients; in non-obese Cushing's patients only, adiponectin was inversely correlated with urinary cortisol (P<0.05). CONCLUSIONS: Glucocorticoids inhibit adiponectin in man, as shown by both exogenous administration to healthy subjects and endogenous cortisol hyperproduction. Similar levels of adiponectin in obese Cushing's patients and their obese controls indicate that obesity per se may act as a predominant factor in masking the relationship between adiponectin and cortisol.
Circulating vascular endothelial growth factor and active renin concentrations and prostaglandin E2 urinary excretion in patients with adrenal tumours
Authors: Zacharieva S , Atanassova I , Orbetzova M , Nachev E , Kalinov K , Kirilov G , Shigarminova R , Ivanova R , Dashev G
Published: January 2005

OBJECTIVES: The aim of the present study was to determine vascular endothelial growth factor (VEGF), prostaglandin E(2) (PGE(2)) and active renin levels in patients with hormonally active adrenal tumours. DESIGN: The study was comprised of 16 patients with primary aldosteronism, 13 patients with active Cushing's syndrome due to adrenal adenomas, 8 patients with adrenal carcinomas, 19 patients with phaeochromocytoma and 19 healthy volunteers. METHODS: Active renin in plasma was determined by a two-site immunoradiometric assay. VEGF in sera samples and PGE(2) in 24-h urine were measured by ELISA. RESULTS: VEGF was significantly elevated in all the four groups of patients as compared with the controls. VEGF levels in patients with Cushing's syndrome were higher than those in patients with primary aldosteronism. Patients with adrenal carcinomas had the highest VEGF levels and the differences reached significance as compared with patients with primary aldosteronism and phaeochromocytoma. PGE(2) levels were not significantly different among groups. Active renin was significantly the lowest in patients with primary aldosteronism and significantly the highest in patients with phaeochromocytoma compared with the controls. Active renin in patients with primary aldosteronism was significantly lower than in those with Cushing's syndrome, phaeochromocytoma and adrenal carcinoma. CONCLUSIONS: Our data indicated that the mean level of VEGF in patients with all investigated adrenal tumours was significantly higher than in healthy controls. The cortisol-producing tumours appear to have increased angiogenic potential. Angiogenesis is probably associated not only with malignancy but also with functional activity of the adrenal tumors.
High prevalence of autoimmune thyroiditis in patients with polycystic ovary syndrome
Authors: Janssen OE , Mehlmauer N , Hahn S , Offner AH , Gartner R
Published: January 2005

OBJECTIVE: To investigate the prevalence of autoimmune thyroiditis (AIT) in patients with polycystic ovary syndrome (PCOS). DESIGN: Over a period of 30 months, 175 patients with PCOS were recruited to a prospective multicenter study to evaluate thyroid function and morphology; 168 age-matched women without PCOS were studied as a control group. METHODS: PCOS was defined as a- or oligomenorrhea, hyperandrogenism and exclusion of other disturbances of estrogen or androgen synthesis. All laboratory parameters were determined with automated immunoassays. Thyroid morphology was assessed by ultrasound. RESULTS: PCOS patients were characterized by an increased LH/FSH ratio, low progesterone, elevated testosterone and a high prevalence of hirsutism (PCOS 83%, control 3%; mean hirsutism score 12+/-5 and 3+/-2 respectively), but no differences in estrogen levels were found. Thyroid function and thyroid-specific antibody tests revealed elevated thyroperoxidase (TPO) or thyroglobulin (TG) antibodies in 14 of 168 controls (8.3%), and in 47 of 175 patients with PCOS (26.9%; P<0.001). On thyroid ultrasound, 42.3% of PCOS patients, but only 6.5% of the controls (P<0.001) had a hypoechoic tissue typical of AIT; while thyroid hormone levels were normal in all subjects, PCOS patients had a higher mean TSH level (P<0.001) and a higher incidence of TSH levels above the upper limit of normal (PCOS 10.9%, controls 1.8%; P<0.001). CONCLUSION: This prospective study demonstrates a threefold higher prevalence of AIT in patients with PCOS, correlated in part with an increased estrogen-to-progesterone ratio and characterized by early manifestation of the disease.
Genomic organization of mouse ZAKI-4 gene that encodes ZAKI-4 alpha and beta isoforms, endogenous calcineurin inhibitors, and changes in the expression of these isoforms by thyroid hormone in adult mouse brain and heart
Authors: Mizuno Y , Kanou Y , Rogatcheva M , Imai T , Refetoff S , Seo H , Murata Y
Published: January 2005

OBJECTIVE: ZAKI-4 was identified as a thyroid hormone-responsive gene in cultured human fibroblasts. A single ZAKI-4 gene encodes two isoforms, ZAKI-4 alpha and beta, both inhibiting calcineurin activity. ZAKI-4 alpha and beta differ at their N termini, and show distinct distribution profiles in human tissues. The aim of this study was to elucidate the organization of the mouse ZAKI-4 gene and to determine the effect of thyroid hormone on the expression of ZAKI-4 isoforms in vivo. DESIGN: We cloned mouse homologues of human ZAKI-4 alpha and beta cDNA. Fluorescence in situ hybridization and bioinformatics analysis were employed to determine the gene organization. The effect of thyroid hormone on the expression of ZAKI-4 isoforms in mouse brain and heart was also studied. METHODS: Total RNA extracted from mouse cerebellum was used to clone ZAKI-4 alpha and beta cDNAs by RT-PCR followed by rapid amplification of cDNA ends. Mice were rendered hypothyroid by feeding a low iodine diet supplemented with propylthiouracil for 2 weeks. In one group (hyperthyroid) L-T(3) was injected i.p. for the last 4 days whereas another group (hypothyroid) received vehicle only. Non-treated mice were controls. RESULTS AND CONCLUSION: Mouse ZAKI-4 alpha and beta cDNAs were highly homologous to the human isoforms. The gene was mapped on chromosome 17qC, syntenic to human chromosome 6 where the human ZAKI-4 gene is located. As observed in human, ZAKI-4 alpha mRNA was expressed only in brain whereas beta mRNA was distributed in other tissues as well, such as heart and skeletal muscle. ZAKI-4 alpha mRNA was lower in the cerebral cortex of hypothyroid mice. Injection of L-T(3) caused an increase in ZAKI-4 beta mRNA in heart; however, expression of neither ZAKI-4 alpha nor beta mRNA was influenced by thyroid status in other tissues. These results indicate that expression of ZAKI-4 alpha and beta isoforms is regulated by thyroid hormone in vivo, and the regulation is isoform- and tissue-specific.
TSH receptor antibodies do not alter the function of gonadotropin receptors stably expressed in eukaryotic cells
Authors: Tonacchera M , Ferrarini E , Dimida A , Agretti P , De Marco G , De Servi M , Chiovato L , Cetani F , Vitti P , Pinchera A
Published: January 2005

OBJECTIVE: TSH receptor (TSHr) mediates the activating action of TSH on the thyroid gland resulting in the growth and proliferation of thyrocytes and thyroid hormone production. TSHr is a major autoantigen in Graves' disease (GD) and is the target for TSHr antibodies. In GD, thyroid-stimulating antibodies (TSAb) are competitive agonists of TSH. In atrophic thyroiditis (AT), thyroid-stimulating blocking antibodies (TSHBAb) are TSH antagonists. The TSHr together with the LH receptor (LHr) and FSH receptor (FSHr) are G-protein-coupled receptors with considerable amino acid homologies in the extracellular domain. We studied the cross-reactivity of the antibodies measured in sera from patients with GD or AT on the LHr and FSHr function. METHODS: We tested the activity of TSAb and TSHBAb in cell lines expressing the LHr and the FSHr. To this purpose a pSVL-FSHr construct was transfected in CHO cells and one clone was used. RESULTS: Twenty-eight sera from patients with GD and four from patients with AT, known to contain TSHr antibodies measured with a radioreceptor assay, were selected. TSAb and TSHBAb activities were measured in CHO cells expressing the TSHr (CHO-TSHr). TSAb and TSHBAb were then tested with the cell lines expressing the LHr and the FSHr for their ability to elicit cAMP accumulation or inhibit FSH/LH-induced cAMP production. None of the TSAb identified was able to stimulate cAMP increase in CHO-LHr or CHO-FSHr. Similarly, none of the TSHBAb was able to block the cAMP response induced by FSH or LH in the respective cell lines. CONCLUSIONS: Our results confirm the notion of the organ-specific nature of the TSHr antibodies.
Pax2 mutant mice display increased number and size of islets of Langerhans but no change in insulin and glucagon content
Authors: Zaiko M , Estreicher A , Ritz-Laser B , Herrera P , Favor J , Meda P , Philippe J
Published: January 2005

Pax2 is a paired box transcription factor expressed in a spatially and temporally restricted manner and its absence results in major developmental defects of the central nervous system, eyes, ears and urogenital system. We recently reported that Pax2 is expressed in pancreatic endocrine cell lines and adult islets of Langerhans and activates glucagon gene expression. We have shown here that the Pax2 gene is expressed during pancreas development as early as embryonic day 10.5. Its absence, as assessed in Pax2(1Neu) mutant mice, results in a two- to threefold increase in the average pancreas volume occupied by the islets in both heterozygous and homozygous mutant mice with a gene-dependent dosage effect. This increase, which is due to a change in the number of islets per unit pancreas volume and in the size of individual islets, is not accompanied by significant modification in the insulin or glucagon content of the pancreas, indicating that the content of these hormones per cell is decreased. We have concluded that Pax2 may be implicated in the prenatal determination of the relative proportion of the endocrine and exocrine tissues of the pancreas.
Mechanisms for altered reproductive function in female rats following neonatal administration of raloxifene
Authors: Tena-Sempere M , Barreiro ML , Aguilar E , Pinilla L
Published: January 2005

OBJECTIVE: Raloxifene is a non-steroidal selective estrogen receptor modulator (SERM) that mimics estrogenic activity on bone density and blood lipid concentration without uterotropic actions. Previous data from our laboratory indicated that, as is the case for estrogen, neonatal administration of raloxifene disturbed normal differentiation of the hypothalamic circuitries governing the gonadotropic axis. In contrast, raloxifene did not act in the same way as estrogen does on the neuronal systems controlling sexual receptivity in the female rat. At present, however, the mechanisms for these organizing effects of raloxifene are not completely elucidated. DESIGN AND METHODS: To analyze this phenomenon, female rats were injected daily with raloxifene (50, 100, 250 or 500 microg/rat per day) between days 1 and 5 of age. On day 23, hypothalamic gonadotropin-releasing hormone (LHRH) mRNA expression was assessed, and pituitary and plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels were measured in basal and LHRH-stimulated conditions. In addition, LH and FSH responses to ovariectomy were evaluated in raloxifene-treated females. Finally, we monitored the ability of neonatal administration of a potent LHRH agonist ([d-Ala(6),d-Gly(10)]-LHRH ethylamide; 0.01 microg/kg per 12 h on days 1-5) to counteract the effects of raloxifene. RESULTS: Our analyses demonstrated that prepubertal rats (23-day-old females) treated neonatally with raloxifene showed decreased hypothalamic LHRH mRNA expression levels, reduced pituitary content of LH and FSH, reduced basal and LHRH-stimulated LH secretion in vivo and in vitro, and decreased response to ovariectomy. In addition, adult females treated neonatally with raloxifene showed anovulation and reduced serum LH levels; these effects were not prevented by the simultaneous administration of a LHRH agonist. CONCLUSION: In conclusion, our data demonstrate that neonatal administration of raloxifene can disrupt the programming of hypothalamic-pituitary-ovarian axis function. Reduced LH secretion, under basal and LHRH-stimulated conditions and after ovariectomy, is probably related to decreased LHRH expression, reduced pituitary LH content and/or decreased pituitary responsiveness to hypothalamic LHRH.