bluuebunny/crossref_metadata_2025 huggingface dataset:
Expression of Genes Encoding Corticotropin-Releasing Factor (CRF), Type 1 CRF Receptor, and CRF-Binding Protein and Localization of the Gene Products in the Human Ovary1
Authors: Asakura H. , Zwain I. H. , Yen S. S. C.
Published: January 2014

Recently, the presence of immunoreactive corticotropin-releasing factor (IrCRF) in the thecal-stromal cells of the human ovary and the ability of CRF to suppress estrogen production by human granulosa cells in vitro have been reported. To understand the functional role of ovarian CRF requires characterization of the human ovarian CRF system, which includes CRF, type 1 CRF receptor (CRF-R1), and the high affinity CRF-binding protein (CRF-BP). Accordingly, we have examined the ovarian CRF system and the cellular distribution of these proteins and their messenger ribonucleic acids (mRNAs) using immunohistochemistry and in situ hybridization, respectively. Normal ovaries from 10 premenopausal women undergoing hysterectomy with ovariectomy were used in the analyses.

IrCRF and its mRNA were localized in thecal cells of small antral and mature follicles. A low abundance of IrCRF and mRNA was also detected in stromal cells of both stages of follicles. Expression of the gene encoding CRF was more prominent in mature follicles than in small antral follicles. CRF-R1 mRNA signal was found exclusively in thecal cells of mature follicles and moderately in small antral follicles. Granulosa cells were devoid of CRF and CRF-R1 mRNAs and proteins. The IrCRF-BP, but not its transcript, was detected in thecal cells and lumen of capillary vessels of the thecal/stromal compartment of mature follicles. The absence of CRF-BP gene transcript in human ovarian follicles was confirmed by reverse transcription-PCR, indicating that the IrCRF-BP detected is not derived from the ovarian transcript and suggesting that the presence of IrCRF-BP and luman of capillary vessels in the thecal compartment originates from the peripheral circulation. Thecal cells of mature follicles, relative to those of small antral follicles, exhibited an intensive immunostaining and mRNA signal for 17α-hydroxylase (P450c17) indicative of androgen biosynthesis. We conclude that the thecal compartment of the human ovary contains a CRF system endowed with CRF and CRF-R1 and the blood-derived CRF-BP. Granulosa cells are devoid of the CRF system. The parallel increases in intensity of CRF, CRF-R1, and 17α-hydroxylase proteins and gene expression with follicular maturation suggest that the intraovarian CRF system may play an autocrine role in androgen biosynthesis with a downstream effect on estrogen production by the granulosa cells. The functionality of the ovarian CRF system may be conditioned by the relative presence of circulating CRF-BP by virtue of its ability to compete with CRF for the CRF receptor.
Long-Term Effect of Testosterone Therapy on Bone Mineral Density in Hypogonadal Men
Authors: Behre Hermann M. , Kliesch Sabine , Leifke Eckhard , Link Thomas M. , Nieschlag Eberhard
Published: January 2014

In both men and women, a decrease in bone mineral density (BMD) is a major symptom of hypogonadism. Although the effects of estrogens on osteoporosis in women are well documented, comparatively little is known about the effects of long term testosterone substitution on BMD in hypogonadal men. Therefore, we studied BMD in 72 hypogonadal patients (37 men with primary and 35 men with secondary hypogonadism) under testosterone substitution therapy that continued for up to 16 yr. Thirty-two of these men were also seen before initiation of therapy. At annual intervals, trabecular BMD of the lumbar spine was measured by quantitative computed tomography, a true volumetric and reproducible method for long term serial BMD measurements. Serum levels of testosterone increased to the normal range in all androgen-treated hypogonadal men. The most significant increase in BMD was seen during the first year of testosterone treatment in previously untreated patients, when BMD increased from 95.2 ± 5.9 to 120.0 ± 6.1 mg/cm3 hydroxyapatite (mean ± se). Long term testosterone treatment maintained BMD in the age-dependent reference range in all 72 hypogonadal men, independent of the type of hypogonadism. Transdermal testosterone patches applied to the scrotum were as effective in normalizing BMD as im testosterone enanthate injections. In summary, testosterone therapy increases BMD in hypogonadal men regardless of age. The greatest increase is seen during the first year of treatment in previously untreated patients with low initial BMD. In hypogonadal men, BMD can be normalized and maintained in the normal range by continuous, long term testosterone substitution.
Increased Serum Concentrations of Human Hepatocyte Growth Factor in Proliferative Diabetic Retinopathy
Authors: Nishimura Masato , Nakano Koji , Ushiyama Masaji , Nanbu Akira , Ohtsuka Ken , Takahashi Hakuo , Yoshimura Manabu
Published: January 2014

Human hepatocyte growth factor (hHGF) is a powerful inducer of angiogenesis. We investigated the relationship between serum hHGF concentrations and proliferative diabetic retinopathy, the major characteristic of which is retinal neovascularization. Serum hHGF concentrations were measured in diabetic (n = 135) and nondiabetic subjects (n = 80). The mean serum hHGF concentration in diabetic subjects without retinopathy was lower than that in nondiabetic subjects [0.041 ± 0.003 ng/mL (n = 62) vs. 0.080 ± 0.010 ng/mL (n = 80); P < 0.05], but was not different from that in diabetic subjects with background retinopathy (0.058 ± 0.007 ng/mL; n = 26) or preproliferative retinopathy (0.048 ± 0.010 ng/mL; n = 10). The mean serum hHGF concentration was increased in subjects with proliferative retinopathy who had not undergone photocoagulation (0.213 ± 0.025 ng/mL; n = 24), but not in those who had undergone photocoagulation (0.040 ± 0.008 ng/mL; n = 13). Circulating hHGF may be involved in the mechanism of neovascularization in the proliferative diabetic retinopathy, and measurement of serum hHGF may be helpful in predicting the presence of proliferative retinopathy in diabetic subjects.
A Prospective Study on Cortisol, Dehydroepiandrosterone Sulfate, and Cognitive Function in the Elderly
Authors: Kalmijn S. , Launer L. J. , Stolk R. P. , de Jong F. H. , Pols H. A. P. , Hofman A. , Breteler M. M. B. , Lamberts S. W. J.
Published: January 2014

The objective of this study was to investigate the relation between the peripheral concentrations of the adrenal steroid hormones cortisol and dehydroepiandrosterone sulfate (DHEAS) and cognitive impairment and decline. A prospective study design was used. The setting was a suburb of Rotterdam, The Netherlands. The study population consisted of a sample of 189 healthy participants from the population-based Rotterdam Study, aged 55–80 yr, who were invited for an additional examination. Follow-up examinations took place 1.9 yr after baseline, on the average. We determined fasting blood levels of DHEAS before dexamethasone administration and of cortisol and corticosteroid-binding globulin before and after the administration of 1 mg dexamethasone overnight. The 30-point Mini-Mental State Examination (MMSE) was used to assess cognition. The associations with cognitive impairment (MMSE score of <26; 6% of the sample) and cognitive decline (drop in MMSE score of >1 point/yr; 24%) were estimated using logistic regression, with adjustment for age, sex, education, and depressive symptoms. An increase of 1 sd in the estimate of free cortisol (sd = 30.3) was associated with cognitive impairment, although not significantly [odds ratio (OR) = 1.5; 95% confidence interval (CI), 0.9–2.4]. A 1 sd increase in the natural logarithm of cortisol after the administration of 1 mg dexamethasone (sd = 0.68) was associated with an OR for cognitive decline of 1.5 (95% CI, 1.0–2.3). A 1 sd increase in DHEAS (sd = 2.10 μmol/L) was inversely, but nonsignificantly, related to cognitive impairment (OR = 0.5; 95% CI, 0.2–1.1) and cognitive decline (OR = 0.6; 95% CI, 0.4–1.1). The ratio of free cortisol over DHEAS was significantly related to cognitive impairment (OR = 1.8; 95% CI, 1.0–3.2). This prospective study among healthy elderly subjects suggested that basal free cortisol levels were positively related to cognitive impairment, and cortisol levels after dexamethasone treatment were related to cognitive decline. There was an inverse, but nonsignificant, association between DHEAS and cognitive impairment and decline.
Mutational Analysis of PHEX Gene in X-Linked Hypophosphatemia1
Authors: Dixon Peter H. , Christie Paul T. , Wooding Carol , Trump Dorothy , Grieff Marvin , Holm Ingrid , Gertner Joseph M. , Schmidtke Jorg , Shah Binita , Shaw Nicholas , Smith Colin , Tau Christina , Schlessinger David , Whyte Michael P. , Thakker Rajesh V.
Published: January 2014

Hypophosphatemic rickets is commonly an X-linked dominant disorder (XLH or HYP) associated with a renal tubular defect in phosphate transport and bone deformities. The XLH gene, referred to as PHEX, or formerly as PEX (phosphate regulating gene with homologies to endopeptidases on the X-chromosome), encodes a 749-amino acid protein that putatively consists of an intracellular, transmembrane, and extracellular domain. PHEX mutations have been observed in XLH patients, and we have undertaken studies to characterize such mutations in 46 unrelated XLH kindreds and 22 unrelated patients with nonfamilial XLH by single stranded conformational polymorphism and DNA sequence analysis. We identified 31 mutations (7 nonsense, 6 deletions, 2 deletional insertions, 1 duplication, 2 insertions, 4 splice site, 8 missense, and 1 within the 5′ untranslated region), of which 30 were scattered throughout the putative extracellular domain, together with 6 polymorphisms that had heterozygosity frequencies ranging from less than 1% to 43%. Single stranded conformational polymorphism was found to detect more than 60% of these mutations. Over 20% of the mutations were observed in nonfamilial XLH patients, who represented de novo occurrences of PHEX mutations. The unique point mutation (a→g) of the 5′untranslated region together with the other mutations indicates that the dominant XLH phenotype is unlikely to be explained by haplo-insufficiency or a dominant negative effect.
Severe Deficiency of 1,25-Dihydroxyvitamin D3 in Human Immunodeficiency Virus Infection: Association with Immunological Hyperactivity and Only Minor Changes in Calcium Homeostasis
Authors: Haug Charlotte J. , Aukrust Pål , Haug Egil , Mørkrid Lars , Müller Fredrik , Frøland Stig S.
Published: January 2014

The serum level of 1,25-dihydroxyvitamin D3[ 1,25-(OH)2D], the biologically most potent metabolite of vitamin D, is tightly regulated within narrow limits in human healthy adults. 1,25-(OH)2D deficiency is rare and is associated with disturbances in calcium and bone metabolism. We have previously reported a marked decrease in serum levels of 1,25-(OH)2D in human immunodeficiency virus (HIV)-infected patients. The present study was designed to further examine the causes and consequences of severe 1,25-(OH)2D deficiency in these patients. The design was a prospective cohort study. Fifty-four HIV-infected patients clinically classified according to the revised criteria from Centers for Disease Control and Prevention and healthy controls were studied. Parameters related to vitamin D and calcium metabolism as well as immunological and nutritional status were determined. Twenty-nine of the patients (54%) had serum levels of 1,25-(OH)2D below the lower reference limit, and 18 of these had undetectable levels. In contrast, HIV-infected patients had normal serum levels of 25-hydroxyvitamin D and vitamin D-binding protein. HIV-infected patients as a group had modestly depressed serum calcium and PTH levels. There were, however, no correlations between these parameters and serum levels of 1,25-(OH)2D. There were no differences in serum calcium or PTH levels or nutritional status when patients with severe 1,25-(OH)2D deficiency were compared to other patients, but patients with undetectable 1,25-(OH)2D had significantly elevated serum phosphate levels. Furthermore, patients with undetectable 1,25-(OH)2D levels were characterized by advanced clinical HIV infection, low CD4+ lymphocyte counts, and high serum levels of tumor necrosis factor-α (TNFα).

We conclude that inadequate 1α-hydroxylation of 25-hydroxyvitamin D seems to be the most likely cause of 1,25-(OH)2D deficiency in HIV-infected patients, possibly induced by an inhibitory effect of TNFα. The low 1,25-(OH)2D and high TNFα levels observed may impair the immune response in HIV-infected patients both independently and in combination and may represent an important feature of the pathogenesis of HIV-related immunodeficiency. Markedly depressed 1,25-(OH)2D serum levels are also present in certain other disorders characterized by immunological hyperactivity. Thus, the findings in the present study may not only represent a previously unrecognized immune-mediated mechanism for induction of 1,25-(OH)2D deficiency in human disease, but may also reflect the importance of adequate serum levels of 1,25-(OH)2D for satisfactory performance of the immune system in man.
Long-Term Effect of Recombinant Human Insulin-Like Growth Factor I on Metabolic and Growth Control in a Patient with Leprechaunism
Authors: Nakae Jun , Kato Mikiko , Murashita Mari , Shinohara Nozomi , Tajima Toshihiro , Fujieda Kenji
Published: January 2014

Leprechaunism is the most severe form of insulin resistance, manifesting with abnormal glucose metabolism and retarded growth. In the present study, we investigated the biological actions of recombinant human insulin-like growth factor I (rhIGF-I) in fibroblasts derived from a patient with leprechaunism. In the same patient, we also investigated the pharmacokinetics of IGF-I and the long-term effect of rhIGF-I treatment on metabolic control and physical growth. The patient’s fibroblasts showed normal binding of IGF-I, normal phosphorylation of the β-subunit of the IGF-I receptor, and normal[ 3H]thymidine incorporation in response to IGF-I. The fibroblast studies suggested that the patient would respond to IGF-I therapy, but certainly did not exclude the possibility of IGF-I resistance in vivo. Administration of recombinant human GH at the dose of 2.0 IU/kg for 3 consecutive days induced a minimal response of serum total IGF-I and IGF-binding protein-3 (IGFBP-3), suggesting partial GH resistance. To increase the serum total IGF-I level, we administered rhIGF-I with combination therapy of intermittent and continuous sc injection. This sustained the serum total IGF-I level, but not the serum IGFBP-3 level, within the normal range. The patient was treated with combination therapy of rhIGF-I by both sc injection and continuous sc infusion for 6 yr and 10 months. Administration of rhIGF-I at total daily dose of 1.6 mg/kg maintained her growth rate and hemoglobin A1c level nearly within the normal range. These findings suggest 1) that this leprechaun patient has an IGF-Ideficient state and partial GH resistance, as reflected by impaired production of IGF-I and IGFBP-3; 2) that rhIGF-I treatment works effectively for preventing postnatal growth retardation and normalizing glucose metabolism in patients with extreme insulin resistance; 3) that this treatment requires relatively higher dose of rhIGF-I; and 4) that treatment appears to be safe and devoid of adverse effects.
Estrogen Receptor Alpha (ER-α) and Beta (ER-β) mRNAs in Normal Ovary, Ovarian Serous Cystadenocarcinoma and Ovarian Cancer Cell Lines: Down-Regulation of ER-β in Neoplastic Tissues
Authors: Brandenberger Alfred W. , Tee Meng Kian , Jaffe Roberts B.
Published: January 2014

The prognosis in ovarian carcinoma, the most lethal of the gynecologic neoplasms, is poor and has changed little in the last three decades. Only a small number respond to antiestrogen therapy, although the classic estrogen receptor, ER-α, has been identified in ovarian surface epithelium, from which approximately 90% of ovarian cancers originate. We have previously shown that ER-β mRNA is most abundant in human fetal ovaries, suggesting that it might play an important role in ovarian development. Therefore, we investigated the mRNA levels of both ERs in normal ovaries, ovarian serous cystadenocarcinomas, granulosa cells from patients undergoing in vitro fertilization (IVF), the ovarian surface epithelium cell line IOSE-Van, and the ovarian cancer cell lines SKOV3, HEY and OCC1.

Northern blots of normal and neoplastic ovaries were hybridized with an ER-β riboprobe that spans the A/B domain. We detected two major hybridizing bands at approximately 8 and 10 kb. An RNase protection assay using the same probe revealed a single band of the expected size. Hybridizing the same blot with an ER-α riboprobe showed a strong hybridizing band at approximately 6.5 kb. In ovarian cancer samples, ER-β mRNA level was decreased when compared to normal ovaries.

Using 25 cycles of RT-PCR followed by Southern blotting, we found equal amounts of ER-α and -β mRNAs in normal ovaries in all age groups from 33 to 75 years; however, in ovarian cancer tissue, the level of ER-α mRNA was similar or slightly higher, comparable to 103 to 104 copies of plasmid DNA, but ER-β mRNA levels were markedly decreased. Granulosa cells from IVF patients expressed high levels of ER-β mRNA. The OSE cell line expressed low level of ER-α, detectable after 40 cycles of RT-PCR and no ER-β mRNA. SKOV3, showed low level of ER-α and β mRNAs, whereas OCC1 showed low level of ER-β and relatively high level of ER-α. HEY did not contain detectable amounts of either ER after 40 cycles of RT-PCR. We found no evidence of differential splicing or major deletions in almost the entire coding region of ER-β in either normal ovaries or tumor samples.
Developmentally Regulated Responses of Human Granulosa Cells to Insulin-Like Growth Factors (IGFs):IGF-I and IGF-II Action Mediated Via the Type-I IGF Receptor1
Authors: Willis Debbie S. , Mason Helen D. , Watson Hazel , Franks Stephen
Published: January 2014

In experimental animal models, insulin-like growth factors (IGFs) have been found to be more potent stimulators of ovarian function than insulin. In human theca cells, however, insulin, IGF-I, and IGF-II have similar effects on androgen production. The relative effects of insulin and IGFs on human granulosa cell steroidogenesis is unknown. Furthermore, it is unclear whether effects of IGF-II on steroidogenesis are mediated by the type-I or type-II IGF receptor.

The effects of insulin, IGF-I, and IGF-II on human granulosa cell steroidogenesis were compared in vitro. As expected, insulin, IGF-I, and IGF-II enhanced steroidogenesis. Previously, IGF-II has been shown to enhance granulosa cell steroid production after insulin preincubation. In this study, an effect of IGF-II, independent of insulin priming, also was observed. In granulosa cell cultures from small antral follicles (≤13 mm), insulin and IGF-I stimulated steroid production to a similar degree, whereas IGF-II was less effective. In contrast, IGFs were more effective than insulin (IGF-I > IGF-II > insulin) in granulosa cells isolated from preovulatory follicles. IGF-I and IGF-II actions were mediated via the type-1 IGF receptor.

The increased responsiveness of mature granulosa cells to IGFs may be an important mechanism by which granulosa cells increase their steroidogenic output in the preovulatory follicle.
Molecular Characterization of the Men1 Tumor Suppressor Gene in Sporadic Pituitary Tumors
Authors: Prezant Toni R. , Levine Jonathan , Melmed Shlomo
Published: January 2014

Anterior pituitary tumors arise sporadically, and also as part of the inherited multiple endocrine neoplasia type 1 (MEN 1) syndrome. To investigate the role of the recently isolated men1 gene in sporadic pituitary tumorigenesis, the complete coding sequence was screened for mutations in 45 sporadic anterior pituitary tumors, including 14 hormone-secreting tumors and 31 nonsecreting tumors, by dideoxy fingerprinting and sequence analysis. No pathogenic sequence changes were found in the men1 coding region. The men1 gene was expressed in 43 of these tumors with sufficient RNA, including one tumor with loss of heterozygosity (LOH) for several polymorphic markers on chromosomal region 11q13. Furthermore, both alleles were expressed in 19 tumors in which the constitutional DNA was heterozygous for intragenic polymorphisms. Thus, inactivation of the men1 tumor suppressor gene, by mutation or by imprinting, does not appear to play a prominent role in sporadic pituitary adenoma pathogenesis.
Troglitazone Regulation of Glucose Metabolism in Human Skeletal Muscle Cultures from Obese Type II Diabetic Subjects1
Authors: Park Kyong Soo , Ciaraldi Theodore P. , Abrams-Carter Leslie , Mudaliar Sunder , Nikoulina Svetlana E. , Henry Robert R.
Published: January 2014

To determine the effects of troglitazone on abnormal skeletal muscle glucose metabolism, muscle cultures from type II diabetic patients were grown for 4–6 weeks and then fused for 4 days either without or with troglitazone (1–5 μg/mL; chronic studies) or had troglitazone added for 90 min (1–5 μg/mL) at completion of fusion (acute studies). Acute troglitazone treatment stimulated glucose uptake, but not glycogen synthase (GS) activity 2-fold (P < 0.05) in a dose-dependent fashion and to the same extent as the addition of maximal (33 nmol/L) insulin. Maximal chronic troglitazone (5 μg/mL for 4 days) increased both glucose uptake (from 9.0 ± 1.5 to 40.9 ± 8.1 pmol/mg protein·min; P < 0.05) and GS fractional velocity (from 5.4 ± 0.7% to 20.6 ± 6.3%; P < 0.05) by approximately 4-fold. At each concentration of chronic troglitazone, glucose uptake rates were similar in the absence and presence of maximal (33 nmol/L) insulin concentrations. In contrast, insulin-stimulated GS activity was greater (P < 0.05) when maximal chronic troglitazone and acute insulin were combined than when chronic troglitazone alone was used. After 4 days of troglitazone, GLUT1 messenger ribonucleic acid and protein increased about 2-fold (P < 0.05) without a change in GLUT4 or GS messenger ribonucleic acid and protein. We conclude that troglitazone has both acute and chronic effects to improve skeletal muscle glucose metabolism of obese type II diabetic subjects. These effects involve direct insulin mimetic stimulatory actions as well as indirect insulin-sensitizing properties.
Circulating Levels of Allopregnanolone in Humans: Gender, Age, and Endocrine Influences
Authors: Genazzani A. R. , Petraglia F. , Bernardi F. , Casarosa E. , Salvestroni C. , Tonetti A. , Nappi R. E. , Luisi S. , Palumbo M. , Purdy R. H. , Luisi M.
Published: January 2014

Allopregnanolone is a neuroactive steroid involved in modulating behavioral functions, stress, and neuroendocrine axes in rats. Changes in plasma allopregnanolone levels throughout the menstrual cycle have been reported in healthy women, but there exists no information on the possible gender or age-related changes or on the source(s) of circulating allopregnanolone. The aim of the present study was to assess serum allopregnanolone concentrations according to gender, menstrual cycle, age, and menopause in normal men and women; serum progesterone (P) and dehydroepiandrosterone (DHEA) levels were evaluated in the same specimens. In addition, the possible source of circulating allopregnanolone in fertile women was investigated by using stimulatory and inhibitory endocrine tests acting on the ovary and/or adrenal cortex.

The present study included 189 fertile women, 112 postmenopausal women, and 46 men. Serum steroid levels were determined after extraction, using specific RIAs. Allopregnanolone levels in fertile women in the follicular phase were similar to those in age-matched men; no significant difference was found between fertile women in the follicular phase and postmenopausal women. The highest levels were found in fertile women during the luteal phase (P< 0.01). An age-related decrease was observed in men (P < 0.01), but not in women. P and DHEA levels were significantly higher in women than in men and were higher in fertile women than in postmenopausal women (P < 0.01). Both P and DHEA showed an age-related decrease in men and women (P < 0.01).

Serum allopregnanolone and P, but not DHEA, significantly increased in response to a GnRH test, whereas corticotropin-releasing factor and ACTH tests elicited a significant increase in allopregnanolone, P, and DHEA levels (P < 0.01). The suppression of adrenal steroidogenesis by dexamethasone markedly reduced both allopregnanolone and DHEA serum levels (P < 0.01).

In conclusion, the present study demonstrated that although men show an age-related decrease, serum allopregnanolone levels in women do not change with age and correlate with P levels during the menstrual cycle and in response to endocrine tests. Ovary and adrenal cortex may be major sources of circulating allopregnanolone in fertile women.
Filter Paper Blood Spot Assay of Human Insulin-Like Growth Factor I (IGF-I) and IGF-Binding Protein-3 and Preliminary Application in the Evaluation of Growth Hormone Status
Authors: Diamandi Anastasia , Khosravi M. Javad , Mistry Jehangir , Martinez Victor , Guevara-Aguirre Jaime
Published: January 2014

To facilitate broader applications of insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) analysis, we developed procedures for their measurements in extracts of whole blood dried on filter paper. A single 8-mm diameter filter paper disc containing about 13 μL blood was used. IGFBP-3 was efficiently extracted in a buffer within 1 h of incubation. IGF-I extraction involved incubation in buffer followed by acidification and neutralization steps. Blood spot assays showed intra- and interassay coefficients of variation (including interspot variations) of 5.4–16.7% for IGF-I and 6.6–11.7% for IGFBP-3; recoveries were 97 ± 7.1% and 101± 8.7%, respectively. Recoveries of IGF-I and IGFBP-3 in response to 4- to 8-fold variations in extraction buffer volume were 97 ± 8.2% and 107 ± 6.1%, respectively. Dried blood spot IGF-I and IGFBP-3 showed greater than 1-month stability at −20 C, 4 C, and room temperature and retained more than 65% of the immunoreactivity after approximately 1 month at 37 C. Both IGF-I and IGFBP-3 were contained within the plasma fraction of whole blood, and variations (mean ± sd) in IGF-I (204 ± 29 μg/L) and IGFBP-3 (4.4± 0.48 mg/L) measured in extracts of dried blood spot with adjusted hematocrit of 0.2–0.62 were acceptable. IGF-I and IGFBP-3 in paired plasma and dried blood spot extracts of random samples (n = 46) showed excellent correlation (r > 0.94) with slopes of near unity. Compared to conventional methods, the filter paper procedures were equally effective in distinguishing IGF-I and IGFBP-3 levels in untreated GH receptor-deficient (n = 11) and age-matched normal controls (n = 16). We conclude that blood collected on filter paper is ideal for IGF-I and IGFBP-3 analysis and may find applications in pediatric and large scale infant screening programs.
Reduced Counterregulation during Hypoglycemia with Raised Circulating Nonglucose Lipid Substrates: Evidence for Regional Differences in Metabolic Capacity in the Human Brain?
Authors: Evans M. L. , Matyka K. , Lomas J. , Pernet A. , Cranston I. C. P. , Macdonald I. , Amiel S. A.
Published: January 2014

abstract

We have investigated the potential for the human brain to use lipid fuels during acute hypoglycemia. Nine healthy male subjects underwent hyperinsulinemic (1.5 mU/kg·min) stepped hypoglycemic clamps on two occasions, infusing Intralipid (20%) and heparin (0.1 U/kg·min) on one occasion only (ILH), with an identical study without infusion of ILH acting as a control. Five subjects also underwent euglycemic clamping with Intralipid/heparin infusion.

During hypoglycemia, ILH raised circulating levels of nonesterified fatty acids, glycerol, and β-hydroxybutyrate, although the latter did not rise until after the onset of counterregulation. With ILH, epinephrine responses [area under the curve (AUC), 127.9 ± 31.7 vs. 175.1 ± 27.4 nmol/L·180 min; P = 0.03] and GH responses (AUC, 260 ± 91 vs. 1009 ± 150, P < 0.01) were reduced and delayed (glucose thresholds, 2.8 ± 0.04 vs. 3.0 ± 0.1 mmol/L; P = 0.04), with a trend toward reduced cortisol responses. Similarly, hypoglycemic symptom scores were diminished during ILH (AUC, 647± 162 vs. 1222 ± 874; P = 0.03). However, there was no significant effect on the deterioration in four-choice reaction time, one measure of cognitive deterioration[ glucose thresholds, 2.6 ± 0.1 vs. 2.7 ± 0.1 mmol/L, ILH vs. control (P = 0.75); AUC, 1420 ± 710 vs. 2250 ± 1080 ms/min (P = 0.59)]. During euglycemic clamping with Intralipid/heparin infusion studies, there was no rise in hormones, four-choice reaction time, or symptoms other than hunger and tiredness.

Both nonesterified fatty acids and glycerol can penetrate the mammalian brain and be metabolized. Raised levels were able to reduce neurohumoral responses to hypoglycemia, but could not protect cognitive function. This suggests that regional differences exist in human brain metabolism between glucose-sensing and cognitive areas of brain, which may be important in the understanding of the mechanisms of glucose sensing and in the genesis of hypoglycemia unawareness in insulin-dependent diabetes.
Outcome of Differentiated Thyroid Cancer in Graves’ Patients1
Authors: Pellegriti Gabriella , Belfiore Antonino , Giuffrida Dario , Lupo Lorenzo , Vigneri Riccardo
Published: January 2014

abstract

The clinical behavior and outcome was evaluated in 21 nonoccult differentiated thyroid carcinomas occurring in Graves’ patients during the period 1982–94 and compared with that of matched tumors occurring in euthyroid controls (n = 70). At surgery, patients with Graves’ disease showed distant metastases more frequently than euthyroid patients (3/21 = 14.3% vs. 1/70 = 1.4%, P = 0.0556). Graves’ patients also showed a significantly higher cumulative risk of recurrent/progressive distant metastases or total adverse events (odd ratios = 3.14 and 2.07, respectively) as compared with euthyroid patients. At the last follow-up visit, persistence of distant metastases was also more frequent in the Graves’ group (P = 0.007), although the cumulative individual dose of radioiodine administered was higher than in the control group (median dose = 805 mCi vs. 350 mCi). Two patients died in the Graves’ group vs. none in the control group. Circulating thyroid stimulating antibodies were present in all patients but one and persisted as long as signs of disease were evident. These findings indicate that differentiated thyroid carcinomas in patients with Graves’ disease are more aggressive than those occurring in matched euthyroid controls and should, therefore, be managed accordingly.
Troglitazone Effects on Gene Expression in Human Skeletal Muscle of Type II Diabetes Involve Up-Regulation of Peroxisome Proliferator-Activated Receptor-γ1
Authors: Park Kyong Soo , Ciaraldi Theodore P. , Lindgren Kristin , Abrams-Carter Leslie , Mudaliar Sunder , Nikoulina Svetlana E. , Tufari Sherrie R. , Veerkamp Jacques H. , Vidal-Puig Antonio , Henry Robert R.
Published: January 2014

abstract

Troglitazone, besides improving insulin action in insulin-resistant subjects, is also a specific ligand for the nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ). To determine whether troglitazone might enhance insulin action by stimulation of PPARγ gene expression in muscle, total PPARγ messenger RNA (mRNA), and protein were determined in skeletal muscle cultures from nondiabetic control and type II diabetic subjects before and after treatment of cultures with troglitazone (4 days ± troglitazone, 11.5μ m). Troglitazone treatment increased PPARγ mRNA levels up to 3-fold in muscle cultures from type II diabetics (277 ± 63 to 630 ± 100 × 103 copies/μg total RNA, P = 0.003) and in nondiabetic control subjects (200 ± 42 to 490 ± 81, P = 0.003). PPARγ protein levels in both diabetic (4.7 ± 1.6 to 13.6± 3.0 AU/10 μg protein, P < 0.02) and nondiabetic cells (7.4 ± 1.0 to 12.7 ± 1.8, P < 0.05) were also up-regulated by troglitazone treatment. Increased PPARγ was associated with stimulation of human adipocyte lipid binding protein (ALBP) and muscle fatty acid binding protein (mFABP) mRNA, without change in the mRNA for glycerol-3-phosphate dehydrogenase, PPARδ, myogenin, uncoupling protein-2, or sarcomeric α-actin protein. In summary, we showed that troglitazone markedly induces PPARγ, ALBP, and mFABP mRNA abundance in muscle cultures from both nondiabetic and type II diabetic subjects. Increased expression of PPARγ protein and other genes involved in glucose and lipid metabolism in skeletal muscle may account, in part, for the insulin sensitizing effects of troglitazone in type II diabetes.
The Effect of a Pure Antiandrogen Receptor Blocker, Flutamide, on the Lipid Profile in the Polycystic Ovary Syndrome
Authors: Diamanti-Kandarakis Evanthia , Mitrakou Asimina , Raptis Sotos , Tolis George , Duleba Antoni J.
Published: January 2014

abstract

Polycystic ovary syndrome (PCOS) is one of the most common endocrinopathies affecting women of reproductive age; it is associated with hyperandrogenism, hyperinsulinemia, and dyslipidemia. This study was designed to assess the long term effects of a pure androgen receptor blocker, flutamide, on the lipid profile in women with PCOS and to examine the possible mechanisms by which androgens may exert their influence. Seventeen women with PCOS (10 obese and 7 lean) were studied. All subjects received a 12-week course of oral flutamide (500 mg/day). The baseline and posttreatment evaluations included lipid profile, androgen levels, insulin sensitivity, and serum catecholamine determinations. The primary outcome was the change in the ratio of low density lipoproteins (LDL) to high density lipoproteins (HDL). Treatment with flutamide was associated with a significant decrease in the LDL/HDL ratio by 23% (P = 0.005), in total cholesterol by 18% (P < 0.0001), in LDL by 13% (P = 0.002), and in triglycerides by 23% (P = 0.002). Flutamide treatment was also associated with a trend toward an increase in HDL (by 14%; P = 0.14). The effects on lipid profile were found regardless of obesity and were not associated with a change in weight. Furthermore, actions of flutamide on lipid metabolism were not associated with significant changes in circulating adrenaline or noradrenaline, glucose metabolism, or insulin sensitivity. This report has demonstrated for the first time that treatment with the pure antiandrogen, flutamide, may improve the lipid profile and that this effect may be due to direct inhibition of androgenic actions.
Polycystic Ovaries Are Inherited as an Autosomal Dominant Trait: Analysis of 29 Polycystic Ovary Syndrome and 10 Control Families
Authors: Govind A. , Obhrai M. S. , Clayton R. N.
Published: January 2014

The aim of this study was to obtain evidence for the genetic basis of polycystic ovaries (PCO) and premature male pattern baldness (PMPB) by screening first-degree relatives of women affected by polycystic ovary syndrome (PCOS). Because of the high prevalence of PCO in the general population, we also studied first-degree relatives of ten asymptomatic control volunteers of reproductive age. The probands were recruited prospectively from infertility and endocrine clinics, where they presented with various clinical symptoms of PCOS. Each had PCO, on transvaginal ultrasound scan. The families of 29 probands and 10 volunteers agreed to take part in the study. Clinical, ultrasound, and biochemical parameters were used to define PCO/PCOS. All female relatives had an ovarian ultrasound scan and hormone profile performed. History was used to assign status in postmenopausal women. All male relatives were assessed for early onset (<30 yr old) male pattern baldness, by photographs. All relatives were assigned affected (PCO/PMPB) or nonaffected status, and segregation analysis was performed.

Of the relatives of 29 PCOS probands, 15 of 29 mothers (52%), 6 of 28 fathers (21%), 35 of 53 sisters (66%), and 4 of 18 brothers (22%) were assigned affected status. First-degree female relatives of affected individuals had a 61% chance of being affected. Of the first-degree male relatives, 22% were affected.

Of a total of 71 siblings of PCOS probands, 39 were affected, giving a segregation ratio of 39/32 (55%), which is consistent with autosomal dominant inheritance for PCO/PMPB. In the control families, 1 of 10 probands (10%), 1 of 10 mothers (10%), no fathers, 2 of 13 sisters (15%), and 1 of 11 brothers (9%) were affected. Of a total of 24 siblings, 3 were affected (13%), giving a segregation ratio (observed/expected) of 3/12, which was significantly different from autosomal dominant inheritance.

The inheritance of PCO and PMPB is consistent with an autosomal dominant inheritance pattern in PCOS families, perhaps caused by the same gene. There was no such genetic influence in families of women without PCOS. Sisters of PCOS probands with polycystic ovarian morphology were more likely to have menstrual irregularity and had larger ovaries and higher serum androstenedione and dehydroepiandrosterone-sulfate levels than sisters without PCO. This suggests a spectrum of clinical phenotype in PCOS families. Men with PMPB had higher serum testosterone than those without. Collectively, these data are consistent with a role for genetic differences in androgen synthesis, metabolism, or action in the pathogenesis of PCOS.
Recovery of Hypopituitarism after Neurosurgical Treatment of Pituitary Adenomas
Authors: Webb Susan M. , Rigla Mercedes , Wägner Anna , Oliver Bartolomé , Bartumeus Frederic
Published: January 2014

Surgery is the treatment of choice for many pituitary tumors; pituitary function may suffer after operation, but relief of pressure on the normal pituitary may also favor postoperative recovery of hypo-pituitarism. The aim of this study was to investigate the frequency of new appearance and recovery of hypopituitarism after neurosurgery and try to identify features associated with it. Pre- and postoperative anterior pituitary functions were investigated in 234 patients with pituitary adenomas (56 nonfunctioning, 71 PRL-secreting, 66 GH-secreting, 39 ACTH-secreting, 1 LH/FSH-secreting, and 1 TSH-secreting tumors). Eighty-eight new postoperative pituitary hypofunctions appeared in 52 patients (12 NF, 14 PRL-secreting, 15 GH-secreting, 10 ACTH-secreting, and 1 LH/FSH-secreting adenomas). They corresponded to 27% ACTH deficiencies (in 29 of the 107 patients with normal preoperative ACTH in whom postoperative evaluation was complete), 14.5% (15 of 103) new GH deficiencies, 10.5% (15 of 143; P < 0.0005, significantly less than ACTH deficiency) new TSH deficiencies, 16.5% (20 of 121) new gonadotropin deficiencies, and 13% (9 of 71) new PRL deficiencies. Preoperatively, 93 were deficient in at least 1 pituitary hormone; after surgery, 45 (48%) recovered between 1 and 3 hormones. The 2 patients with LH/FSH- and TSH-secreting macroadenomas did not recover pituitary function. Factors associated with a higher probability of postoperative pituitary function recovery were: no tumor rests on postoperative pituitary imaging (P = 0.001) and no neurosurgical (P = 0.001) or pathological evidence (P = 0.049) of an invasive nature. Tumor size did not differ significantly between those who did and those who did not recover pituitary function after surgery.

Even if clear hypofunction is observed at initial work-up, patients should be reassessed after surgery without substitution therapy, because practically half the preoperative pituitary hormone deficiencies recover postoperatively, eliminating the need for life-long substitution therapy.
Pharmacokinetics, Efficacy, and Safety of a Permeation-Enhanced Testosterone Transdermal System in Comparison with Bi-Weekly Injections of Testosterone Enanthate for the Treatment of Hypogonadal Men*
Authors: Dobs Adrian S. , Meikle A. Wayne , Arver Stefan , Sanders Steven W. , Caramelli Kim E. , Mazer Norman A.
Published: January 2014

The pharmacokinetics, efficacy, and safety of the Androderm testosterone (T) transdermal system (TTD) and intramuscular T enanthate injections (IM) for the treatment of male hypogonadism were compared in a 24-week multicenter, randomized, parallel-group study. Sixty-six adult hypogonadal men (22–65 years of age) were withdrawn from prior IM treatment for 4–6 weeks and then randomly assigned to treatment with TTD (two 2.5-mg systems applied nightly) or IM (200 mg injected every 2 weeks); there were 33 patients per group. Twenty-six patients in the TTD group and 32 in the IM group completed the study.

TTD treatment produced circadian variations in the levels of total T, bioavailable T, dihydrotestosterone, and estradiol within the normal physiological ranges. IM treatment produced supraphysiological levels of T, bioavailable T, and estradiol (but not dihydrotestosterone) for several days after each injection. Mean morning sex hormone levels were within the normal range in greater proportions of TTD patients (range, 77–100%) than IM patients (range, 19–84%). Both treatments normalized LH levels in approximately 50% of patients with primary hypogonadism; however, LH levels were suppressed to the subnormal range in 31% of IM patients vs. 0% of TTD patients. Both treatments maintained sexual function (assessed by questionnaire and Rigiscan) and mood (Beck Depression Inventory) at the prior treatment levels.

Prostate-specific antigen levels, prostate volumes, and lipid and serum chemistry parameters were comparable in both treatment groups. Transient skin irritation from the patches was reported by 60% of the TTD patients, but caused only three patients (9%) to discontinue treatment. IM treatment produced local reactions in 33% of patients and was associated with significantly more abnormal hematocrit elevations (43.8% of patients) compared with TTD treatment (15.4% of patients). Gynecomastia resolved more frequently during TTD treatment (4 of 10 patients) than with IM treatment (1 of 9 patients).

Although both treatments seem to be efficacious for replacing T in hypogonadal men, the more physiological sex hormone levels and profiles associated with TTD may offer possible advantages over IM in minimizing excessive stimulation of erythropoiesis, preventing/ameliorating gynecomastia, and not over-suppressing gonadotropins.
A Critical Evaluation of Simple Methods for the Estimation of Free Testosterone in Serum
Authors: Vermeulen Alex , Verdonck Lieve , Kaufman Jean M.
Published: January 2014

The free and nonspecifically bound plasma hormone levels generally reflect the clinical situation more accurately than total plasma hormone levels. Hence, it is important to have reliable indexes of these fractions. The apparent free testosterone (T) concentration obtained by equilibrium dialysis (AFTC) as well as the fraction of serum T not precipitated by 50% ammonium sulfate concentration (non-SHBG-T; SHBG, sex hormone-binding globulin), often referred to as bioavailable T, appear to represent reliable indexes of biologically readily available T, but are not well suited for clinical routine, being too time consuming. Several other parameters have been used without complete validation, however: direct immunoassay of free T with a labeled T analog (aFT), calculation of free T (FT) from total T and immunoassayed SHBG concentrations (iSHBG), and the free androgen index (FAI = the ratio 100T/iSHBG). In the view of substantial discrepancies in the literature concerning the free or bioavailable T levels, we compared AFTC, FT, aFT, FAI, and non-SHBG-T levels in a large number of sera with SHBG capacities varying from low, as in hirsute women, to extremely high as in hyperthyroidism. All these indexes of bioavailable T correlated significantly with the AFTC concentration; AFTC and FT values were almost identical under all conditions studied, except during pregnancy. Values for aFT, however, were only a fraction of either AFTC or FT, the fraction varying as a function of SHBG levels. Also, the FAI/AFTC ratio varied as a function of the SHBG levels, and hence, neither aFT nor FAI is a reliable index of bioavailable T.

The FT value, obtained by calculation from T and SHBG as determined by immunoassay, appears to be a rapid, simple, and reliable index of bioavailable T, comparable to AFTC and suitable for clinical routine, except in pregnancy. During pregnancy, estradiol occupies a substantial part of SHBG-binding sites, so that SHBG as determined by immunoassay overestimates the actual binding capacity, which in pregnancy sera results in calculated FT values that are lower than AFTC. The nonspecifically bound T, calculated from FT, correlated highly significantly with and was almost identical to the values of non-SHBG-T obtained by ammonium sulfate precipitation, testifying to the clinical value of FT calculated from iSHBG.
Leptin Suppression of Insulin Secretion and Gene Expression in Human Pancreatic Islets: Implications for the Development of Adipogenic Diabetes Mellitus1
Authors: Seufert Jochen , Kieffer Timothy J. , Leech Colin A. , Holz George G. , Moritz Wolfgang , Ricordi Camillo , Habener Joel F.
Published: January 2014

Previously we demonstrated the expression of the long form of the leptin receptor in rodent pancreatic β-cells and an inhibition of insulin secretion by leptin via activation of ATP-sensitive potassium channels. Here we examine pancreatic islets isolated from pancreata of human donors for their responses to leptin. The presence of leptin receptors on islet β-cells was demonstrated by double fluorescence confocal microscopy after binding of a fluorescent derivative of human leptin (Cy3-leptin). Leptin (6.25 nm) suppressed insulin secretion of normal islets by 20% at 5.6 mm glucose. Intracellular calcium responses to 16.7 mm glucose were rapidly reduced by leptin. Proinsulin messenger ribonucleic acid expression in islets was inhibited by leptin at 11.1 mm, but not at 5.6 mm glucose. Leptin also reduced proinsulin messenger ribonucleic acid levels that were increased in islets by treatment with 10 nm glucagon-like peptide-1 in the presence of either 5.6 or 11.1 mm glucose. These findings demonstrate direct suppressive effects of leptin on insulin-producingβ -cells in human islets at the levels of both stimulus-secretion coupling and gene expression. The findings also further indicate the existence of an adipoinsular axis in humans in which insulin stimulates leptin production in adipocytes and leptin inhibits the production of insulin in β-cells. We suggest that dysregulation of the adipoinsular axis in obese individuals due to defective leptin reception byβ -cells may result in chronic hyperinsulinemia and may contribute to the pathogenesis of adipogenic diabetes.