bluuebunny/crossref_metadata_2025 huggingface dataset:
Progesterone Prevents Sleep Disturbances and Modulates GH, TSH, and Melatonin Secretion in Postmenopausal Women
Authors: Caufriez Anne , Leproult Rachel , L'Hermite-Balériaux Mireille , Kerkhofs Myriam , Copinschi Georges
Published: January 2014

Context:

A number of neuroactive progesterone metabolites produce sedative-like effects. However, the effects of progesterone administration on sleep are not well characterized.

Objective:

To investigate the effects of a 3-wk progesterone administration on sleep architecture and multiple hormonal profiles.

Subjects:

Eight healthy postmenopausal women, 48–74 yr old, without sleep complaints or vasomotor symptoms. None was on hormone replacement therapy. They did not take any medication for ≥2 months.

Design:

Randomized, double-blind, placebo-controlled study. For 3 wk, subjects took daily at 2300 h a capsule of either 300 mg of progesterone or placebo. Sleep was polygraphically recorded during the last two nights, and blood samples were obtained at 15-min intervals for 24 h.

Results:

During the first night (no blood sampling), sleep was similar in both conditions. Under placebo, blood sampling procedure was associated with marked sleep disturbances, which were considerably reduced under progesterone treatment: mean duration of wake after sleep onset was 53% lower, slow-wave sleep duration almost 50% higher, and total slow-wave activity (reflecting duration and intensity of deep sleep) almost 45% higher under progesterone than under placebo (P ≤ 0.05). Nocturnal GH secretion was increased, and evening and nocturnal TSH levels were decreased under progesterone (P ≤ 0.05).

Conclusions:

Progesterone had no effect on undisturbed sleep but restored normal sleep when sleep was disturbed (while currently available hypnotics tend to inhibit deep sleep), acting as a “physiologic” regulator rather than as a hypnotic drug. Use of progesterone might provide novel therapeutic strategies for the treatment of sleep disturbances, in particular in aging where sleep is fragmented and of lower quality.
A Resveratrol and Polyphenol Preparation Suppresses Oxidative and Inflammatory Stress Response to a High-Fat, High-Carbohydrate Meal
Authors: Ghanim Husam , Sia Chang Ling , Korzeniewski Kelly , Lohano Teekam , Abuaysheh Sanaa , Marumganti Anuritha , Chaudhuri Ajay , Dandona Paresh
Published: January 2014

Background:

High-fat, high-carbohydrate (HFHC) meals are known to induce oxidative and inflammatory stress, an increase in plasma endotoxin concentrations, and an increase in the expression of suppressor of cytokine signaling-3 (SOCS-3).

Hypothesis:

The intake of a nutritional supplement containing resveratrol and muscadine grape polyphenols reduces HFHC meal-induced oxidative and inflammatory stress and stimulates the activity of the antioxidant transcription factor, Nrf-2, and its downstream targets.

Methods:

Ten normal, healthy subjects were given a 930-kcal HFHC meal either with placebo or with the supplement. Indices of oxidative stress, inflammation, Nrf-2 binding activity, the concentrations of endotoxin (lipopolysaccharide) and lipoprotein binding protein (LBP), and the expression of TLR-4, CD14, IL-1β, TNFα, SOCS-3, Keap-1, NQO-1, and GST-P1 were measured.

Results:

The intake of the supplement suppressed the meal-induced elevations of plasma endotoxin and LBP concentrations, the expression of p47phox, TLR-4, CD14, SOCS-3, IL-1β, and Keap-1, while enhancing Nrf-2 binding activity and the expression of NQO-1 and GST-P1 genes.

Conclusion:

A supplement containing resveratrol and muscadine polyphenols reduces the magnitude of oxidative stress, increase in lipopolysaccharide and LBP and TLR-4, CD14, IL-1β and SOCS-3 expression after an HFHC meal. It also stimulates specific Nrf-2 activity and induces the expression of the related antioxidant genes, NQO-1 and GST-P1. These results demonstrate the acute antioxidant and antiinflammatory effects of resveratrol and polyphenolic compounds in humans in the postprandial state.
Premature Ovarian Failure in Patients with Autoimmune Addison's Disease: Clinical, Genetic, and Immunological Evaluation
Authors: Reato G. , Morlin L. , Chen S. , Furmaniak J. , Rees Smith B. , Masiero S. , Masiero S. , Albergoni M. P. , Zanchetta R. , Betterle C.
Published: January 2014

Design

The design of the study was to investigate the prevalence of the following: 1) premature ovarian failure (POF) in patients with autoimmune Addison's disease (AD); 2) steroidproducing cells (StCA) and steroidogenic enzymes (17α-hydroxylase autoantibodies and P450 side-chain cleavage enzyme autoantibodies) in patients with or without POF; and 3) the value of these autoantibodies to predict POF.

Patients

The study included 258 women: 163 with autoimmune polyendocrine syndrome type 2 (APS-2), 49 with APS-1, 18 with APS-4, and 28 with isolated AD.

Methods

StCA were measured by an immunofluorescence technique and 17α-hydroxylase autoantibodies and P450 sidechain cleavage enzyme autoantibodies by immunoprecipitation assays.

Results

Fifty-two of 258 women with AD (20.2%) had POF. POF was diagnosed in 20 of 49 (40.8%) with APS-1, six of 18 (33.3%) with APS-4, 26 of 163 (16%) with APS-2, and none of 28 with isolated AD. In patients with APS-1 and APS-4, POF developed after AD, whereas it preceded AD in patients with APS-2. StCA were detected in 31 of 43 with POF (72%) and 51 of 198 without POF (25.7%). StCA were present in 22 of 38 with APS-1 (57.9%) (11 of 13 with POF); in five of 13 with APS-4 (38.5%) (three of four with POF); in 53 of 162 with APS-2 (32.7%) (17 of 26 with POF), and in one of 28 isolated AD patients (3.6%). Twelve of 13 patients with POF with a duration less than 5 yr (92.3%) and 18 of 25 with duration longer than 5 yr (72%) were StCA positive. Twenty-eight of 31 with POF (90.3%) were positive for at least one steroidogenic antibody. Forty-one women with AD less than 40 yr were followed up for a mean period of 9 yr. Eight of 21 women (38%) positive or seroconverted for steroidogenic autoantibodies developed POF at a mean age of 23 yr (six with APS-1, one with APS-2, and one with APS-4), and none of the 20 patients negative for steroidogenic autoantibodies developed POF.

Conclusions

This study indicates that AD is frequently associated with POF and that steroidogenic antibodies are markers of patients with POF. Steroidogenic autoantibodies are predictive markers of POF in patients with AD.
Thyroid Function in Rubinstein-Taybi Syndrome*
Authors: Olson David P. , Koenig Ronald J.
Published: January 2014

Rubinstein-Taybi syndrome (RTS) is a genetic syndrome characterized by broad thumbs and halluces, growth retardation, mental retardation, and craniofacial abnormalities. This condition recently was found to be caused by mutations in the gene encoding cAMP response element-binding protein (CREB)-binding protein. As CREB-binding protein has been shown to be a critical coactivator for thyroid hormone receptors, it is plausible that RTS would be characterized by thyroid hormone resistance. In fact, features of RTS, such as mental retardation and short stature, are consistent with thyroid hormone deficiency or resistance. To assess the function of the thyroid axis in RTS, free T4 and TSH were measured in 12 subjects with this syndrome. The free T4 level was normal in all 12 (mean ± sd, 0.97 ± 0.20 ng/dL; normal range, 0.73–1.79), as was the TSH level (2.24 ± 0.87 μU/mL; normal range, 0.3–6.5). Thus, overt thyroid hormone resistance does not appear to be a typical feature of RTS.
Thyrotropin Levels during Hydrocortisone Infusions That Mimic Fasting-Induced Cortisol Elevations: A Clinical Research Center Study1
Authors: Samuels M. H. , McDaniel P. A.
Published: January 2014

Both short term fasting and administration of high doses of glucocorticoids lead to marked suppression of serum TSH levels in healthy subjects. However, it is not known whether the more mild serum cortisol elevations seen during fasting can account for fasting-induced TSH suppression. To study this question, eight healthy subjects each underwent three 2-day studies: 1) baseline (ad libitum diet), 2) fasting (56 h of total caloric deprivation), 3) hydrocortisone (HC) infusions at a dose and pulsatile pattern that reproduced cortisol levels measured during each subject’s fasting study. Subjects required 34–46 mg HC/24 h to achieve these cortisol levels. During each study, blood samples were drawn every 15 min during the final 24 h for serum cortisol and TSH levels. A TRH stimulation test was performed at the end of each study. By design, fasting and HC infusions induced similar mild increases in 24-h serum cortisol levels (32% over baseline), with the most significant increases seen between 1400–0200 h. Fasting decreased 24-h mean and pulsatile TSH levels 65% from baseline, whereas HC infusions decreased mean and pulsatile TSH levels 51% from baseline. Daytime (0800–0200 h) TSH levels were identical in the two studies, whereas nocturnal (0200–0800 h) TSH levels during HC infusions fell midway between baseline and fasting studies. Serum total T3 and TSH responses to TRH were decreased to a similar degree by fasting or HC infusions. These results suggest that mild elevations in endogenous cortisol levels may mediate at least in part fasting-induced changes in TSH secretion and thyroid hormone levels. In addition, these data show that near-physiological doses of HC and resulting changes in serum cortisol levels within the normal range can cause significant decreases in serum TSH levels.
Hereditary Defect in Biosynthesis of Aldosterone: Aldosterone Synthase Deficiency 1964–19971
Authors: Peter Michael , Fawaz Lubna , Drop Stenvert L. S. , Visser Hendrik K. A. , Sippell Wolfgang G.
Published: January 2014

We studied two of the three patients with a hereditary defect in the biosynthesis of aldosterone originally described by Visser and Cost in 1964. All three presented as newborns with salt-losing syndrome and failure to thrive. The original biochemical studies showed a defect in the 18-hydroxylation of corticosterone. According to the nomenclature proposed by Ulick, this defect would be termed corticosterone methyl oxidase deficiency type I. We measured plasma steroids in the untreated adult patients and performed molecular genetic studies. Aldosterone and 18-OH-corticosterone were decreased, whereas corticosterone and 11-deoxycorticosterone were elevated, thus confirming the diagnosis of corticosterone methyl oxidase deficiency type I. Cortisol and its precursors were in the normal range. Genetic defects in the gene CYP11B2 encoding aldosterone synthase (P450c11Aldo) have been described in a few cases. We identified a homozygous single base exchange (G to T) in codon 255 (GAG) causing a premature stop codon E255X (TAG). This mutation destroys a Aoc II restriction site. Digestion of a PCR fragment containing exon 4 of CYP11B2 (261 bp) with this restriction enzyme revealed in the two patients homozygous for the E255X mutation only a 261-bp fragment, whereas the heterozygous parents had three fragments (261 bp from the mutant allele and 194 and 67 bp from the wild-type allele). The mutant enzyme had lost the five terminal exons containing the heme binding site, and thus there was a loss of function enzyme. We conclude that the biochemical phenotype of these prismatic cases of congenital hypoaldosteronism can be explained by the patients genotype.
Dose-Dependent Effects of Recombinant Human Interleukin-6 on Glucose Regulation
Authors: Tsigos Constantine , Papanicolaou Dimitris A. , Kyrou Ioannis , Defensor Ruby , Mitsiadis Constantine S. , Chrousos George P.
Published: January 2014

Inflammatory cytokines have metabolic actions that probably contribute to the general adaptation of the organism during infectious or inflammatory stress. To examine the effects of interleukin 6 (IL-6), the main circulating cytokine, on glucose metabolism in man, we performed dose-response studies of recombinant human IL-6 in normal volunteers. Increasing single doses of IL-6 (0.1, 0.3, 1.0, 3.0, and 10.0 mg/Kg BW) were injected sc in 15 healthy male volunteers (3 in each dose) after a 12-h fast. All IL-6 doses were tolerated well and produced no significant adverse effects. We measured the circulating levels of glucose, insulin, C-peptide, and glucagon at baseline and half-hourly over 4 h after the IL-6 injection. Mean peak plasma levels of IL-6 were achieved between 120 and 240 min and were 8, 22, 65, 290, and 4050 pg/mL, respectively, for the 5 doses. After administration of the 2 smaller IL-6 doses, we observed no significant changes in plasma glucose levels, which, because of continued fasting, decreased slightly over time. By 60 min after the 3 higher IL-6 doses, however, the decline in fasting blood glucose was arrested, and glucose levels increased in a dose-dependent fashion. The concurrent levels of plasma insulin and C-peptide were not affected by any IL-6 dose. In contrast, IL-6 caused significant increases in plasma glucagon levels, which peaked between 120 and 150 min after the IL-6 injection. In conclusion, sc IL-6 administration induced dose-dependent increases in fasting blood glucose, probably by stimulating glucagon release and other counteregulatory hormones and/or by inducing peripheral resistance to insulin action.
G Protein and Thyrotropin Receptor Mutations in Thyroid Neoplasia*
Authors: Esapa Christopher , Foster Sally , Johnson Sarah , Jameson J. Larry , Kendall-Taylor Patricia , Harris Philip E.
Published: January 2014

The cAMP pathway plays a central role in thyroid follicular cell growth and function. Mutations of the TSH receptor (TSHR) or G proteins (gsp) that activate adenylyl cyclase have been identified in autonomously functioning thyroid nodules. Gsp mutations have been identified also in other forms of thyroid neoplasia, but their reported prevalence has been extremely variable. We have studied the prevalence of gsp mutations and activating mutations of Gi2α (gip) in a series of 66 benign and 34 malignant thyroid tumors. Thirty-six tumors were from Boston and 64 from the UK. In addition, we examined the 64 UK tumors for mutations of the TSHR gene. DNA extracted from fresh-frozen or paraffin-embedded tissue was amplified by PCR and examined for mutations using oligonucleotide-specific hybridization and single-strand conformation polymorphism analysis. No G protein gene mutations were identified in the Boston tumors. One gsp mutation, R201C, in a Hürthle cell adenoma and 1 gip mutation, R179C, in a follicular adenoma were demonstrated in tumors from the UK. Oligonucleotide-specific hybridization and single-strand conformation polymorphism analysis of the UK tumors did not demonstrate any mutations of the TSHR gene. Eleven normal thyroid tissue samples were wild-type for Gsα, Gi2α, and the TSHR gene.
Parathyroid Hormone-Related Protein-(1–36) Is Biologically Active When Administered Subcutaneously to Humans1
Authors: Henry Jean G. , Mitnick Maryann , Dann Pamela R. , Stewart Andrew F.
Published: January 2014

PTH-related protein (PTHrP) is responsible for most cases of humoral hypercalcemia of malignancy (HHM). It mimics the actions of PTH as a result of its structural homology with PTH and its ability to bind to and signal via the PTH/PTHrP receptor in bone and kidney. PTHrP-(1–36) appears to be one of several secretory forms of PTHrP. This peptide has been administered iv to normal volunteers previously and has been shown to produce effects that are qualitatively and quantitatively the same as those produced by PTH-(1–34). To determine whether PTHrP-(1–36) could be used sc in humans as a diagnostic reagent for elucidating the differences between HHM and hyperparathyroidism, we performed a 12-h dose-finding study examining whether sc PTHrP-(1–36) could elicit effects on mineral homeostasis.

PTHrP-(1–36) administered sc in three doses (0.82, 1.64, and 3.28μ g/kg) to 21 normal women produced increases in circulating PTHrP-(1–36), reductions in serum phosphorus and the renal phosphorus threshold, increments in fractional calcium excretion and nephrogenous cAMP excretion, and increases in plasma 1,25-dihydroxyvitamin D. These changes were highly significant in statistical terms and were observed at doses that had no effect on serum calcium or endogenous PTH.

These studies demonstrate the feasibility of using PTHrP-(1–36) as a diagnostic probe for future studies aimed at elucidating the differing pathophysiologies of HHM and hyperparathyroidism.
Generation and Characterization of an IGFBP-7 Antibody: Identification of 31kD IGFBP-7 in Human Biological Fluids and Hs578T Human Breast Cancer Conditioned Media
Authors: Wilson Elizabeth M. , Oh Youngman , Rosenfeld Ron G.
Published: January 2014

The cDNA encoding mac25 (IGFBP-7) was first derived from mRNA isolated from leptomeningial and senescent human mammary epithelial cells (1, 2). The open reading frame was shown to predict a protein with homology to the amino terminus of the IGF binding proteins, (IGFBP)1-6. Studies in our laboratory have shown that baculovirus generated mac25 binds IGF-I and-II in a specific manner, leading to the renaming of mac25 as IGFBP-7 (3). Further studies at the cellular level, to identify the involvement of IGFBP-7 in IGF regulation and cell growth, require a specific antibody against the protein, which has yet to be identified in either culture cells or in vivo. We have now generated three polyclonal antibodies against the purified baculovirus peptide, and, by western immunoblots and immunoprecipitation, demonstrated the existence of a specific 31,000 dalton protein. It is a secreted protein and can be identified in the conditioned media of Hs578T breast cancer cells, as well as in normal human urine, cerebrospinal fluid, and amniotic fluid. Subsequent studies with these antibodies should help elucidate the physiological role(s) of this protein.
Heterogeneity of the Human Corticotropin-Releasing Factor-Binding Protein
Authors: Woods R. J. , Kemp C. F. , David J. , Lowry P. J.
Published: January 2014

Human corticotropin-releasing factor (hCRF), secreted by the placenta, principally in the third trimester, is specifically bound in the peripheral circulation to a 37-kDa binding protein (CRF-BP). This complex is cleared from the circulation. We postulate that the protein may be returned to the blood in a form that is immunologically altered and not well recognized by the reported RIAs. We report that a stable isoform can result from temporary denaturation of recombinant CRF-BP by 8 mol/L urea. This isoform, urea-treated binding protein, which can bind CRF, has been found to bind to an antibody raised against a synthetic peptide comprising the first 24 amino acid residues of CRF-BP, but not to a second similar N-terminal antibody, although it was closely matched in titer. Urea-treated binding protein also cross-reacts poorly in the RIA with CRF-BP. It is proposed that as a result of in vivo post-ligand binding events, isoforms may be susceptible to cleavage. After affinity purification, which involves denaturation, recombinant CRF-BP was often found to be cleaved after storage in the presence of protease inhibitors.

Here we present evidence for a C-terminally truncated form of the native binding protein in the plasma of subjects suffering from rheumatoid arthritis, which may parallel the in vitro truncation.
Intraoperative Adrenocorticotropin Levels During Transsphenoidal Surgery for Cushing’s Disease Do Not Predict Cure
Authors: Graham Kathryn E. , Samuels Mary H. , Raff Hershel , Barnwell Stanley L. , Cook David M.
Published: January 2014

Recently, intraoperative rapid immunochemiluminometric assay (ICMA) ACTH measurements have been used to evaluate the completeness of resection of ectopic ACTH-secreting tumors. This study evaluates whether this method can be applied to patients undergoing transsphenoidal surgery (TSS) for Cushing’s disease to predict complete pituitary tumor resection.

Eighteen patients with Cushing’s disease undergoing TSS had plasma ACTH concentrations measured by a standard ICMA every 10 min for 1 h immediately after pituitary tumor removal. Patients were evaluated postoperatively for cure by standard criteria. ACTH levels were evaluated for percentage decrease from baseline at each time point.

Patients who were cured (n = 11) had statistically greater decreases in ACTH levels (mean decrease 54%) than patients who were not (n = 7; 26% mean decrease, P < 0.04). By Receiver-Operator Characteristic (ROC) analysis, a reduction of at least 40% best predicted which patients were cured and which were not cured. This level of reduction was observed in 82% of cured patients, and a reduction of less than 40% was observed in 71% of those not cured. The analysis misclassified 4 of the 18 patients, resulting in a diagnostic accuracy of 78%.

Although the mean maximal decrease in ACTH concentrations after tumor removal was significantly different between cured and not cured patients with Cushing’s disease, it was less dramatic than results in the previous ectopic ACTH study. This may relate to incomplete suppression and/or surgical manipulation of normal pituitary corticotrophs in patients with pituitary disease. In summary, in contrast to the ectopic ACTH syndrome, decline of plasma ACTH during TSS does not accurately predict complete tumor resection.
Antiresorptive Therapy in Hyperthyroid Patients: Longitudinal Changes in Bone and Mineral Metabolism
Authors: Jódar Esteban , Muñoz-Torres Manuel , Escobar-Jiménez Fernando , Quesada Miguel , Luna Juan D. , Olea Nicolás
Published: January 2014

The effect of antiresorptive therapy with nasal calcitonin (CT) in recently diagnosed hyperthyroid patients on conventional medical therapy as well as the evolution of bone metabolism were assessed. Forty-five patients with recent-onset hyperthyroidism (<12 weeks) were sex and menopause stratified and randomly allocated to treatment with carbimazole (Neotomizol), carbimazole plus low dose CT (Calsynar; 100 IU/day, 2 days/week), or carbimazole plus high dose CT (Calsynar; 100 IU/day, 14 days/month). Bone mineral density was measured by dual x-ray absorptiometry in lumbar spine, femoral neck, and Ward’s triangle at 0, 9, and 18 months of treatment. We also determined free T4, free T3, TSH, osteocalcin, total and bone alkaline phosphatases, tartrate-resistant acid phosphatase, type I collagen C telopeptide, and urinary hydroxyproline every 3 months of follow-up. No significant difference was observed among treatments. A euthyroid state was attained at 3 months. Bone mass increased significantly at the 9 month evaluation (P < 0.05), with a 5–10% net gain during follow-up. Nevertheless, final bone mass was 4–8% smaller than expected. Bone formation markers were increased at 0 and 3 months, with reductions at 6–9 months; resorption bone markers showed a significant reduction at the 3 month evaluation.

These results indicate that the euthyroid state partially reduces hyperthyroidism-associated osteopenia, with a bone mass recovery period during the 6–9 early months of effective treatment. This recovery phase is characterized by raised bone formation markers and reduced bone resorption markers. The treatment with nasal CT at the doses assayed has no additional effect over that of attainment of the euthyroid state.
Interleukin-6 and the Interleukin-6 Receptor in the Human Adrenal Gland: Expression and Effects on Steroidogenesis1
Authors: Päth Günter , Bornstein Stefan R. , Ehrhart-Bornstein Monika , Scherbaum Werner A.
Published: January 2014

Interleukin (IL)-6 is a potent activator of the human hypothalamic-pituitary-adrenal axis. After chronic administration of IL-6 in humans, there is a substantial elevation of cortisol, whereas ACTH levels are blunted. Thus, we investigated whether IL-6 and/or the IL-6 receptor (IL-6R) are expressed in the human adrenal gland and whether IL-6 could cause the release of steroid hormones by a direct action on adrenal cells in primary culture. The expression of IL-6 and IL-6R was investigated with RT-PCR and immunohistochemistry, and the effects on human adrenal steroidogenesis were tested with IL-6 in vitro. To avoid effects mediated by macrophages, we depleted adrenal primary cultures from macrophages using specific mouse antihuman CD68 and sheep antimouse IgG conjugated magnetic beads. The results showed that: 1) IL-6 and IL-6R are expressed in adrenal cell cultures, including all cell types and those depleted of macrophages; 2) IL-6R is mainly expressed in the zona reticularis and the inner zona fasciculata; positive signals from the zona glomerulosa and the medulla occurred in single cells; and 3) IL-6 regulates adrenal synthesis of mineralocorticoids, glucocorticoids, and androgens in vitro, dependent on time and dose, in the absence of macrophages. After 24 h, aldosterone secretion increased to 172 ± 28% sem, cortisol to 177 ± 27% sem, and dehydroepiandrosterone to 153 ± 20% sem of basal secretion. These findings, in combination with previous investigations, suggest that IL-6 exerts its acute action via the hypothalamus and the pituitary. In the adrenal gland, however, IL-6 seems to be a long-term regulator of stress response, integrating the responses of all cortical zones to stimuli from the immune and endocrine system.
Suppression of Tyrosine Kinase Activity Inhibits[ 3H]Thymidine Uptake in Cultured Human Pituitary Tumor Cells1
Authors: Jones T. H. , Justice S. K. , Price A.
Published: January 2014

Tyrosine kinases are involved in the phosphorylation of proteins that regulate cell growth and proliferation. The mitogenic effect of several growth factors requires tyrosine kinase activity of their receptors. The effect of inhibition of tyrosine kinase activity on thymidine uptake into cultured human pituitary adenoma cells was studied using two inhibitors, genestein and methyl-2,3-dihydroxycinnamate (MDHC).

Of 33 pituitary adenomas, 7 incorporated sufficient[ 3H]thymidine to be investigated in the experiments. Genestein and MDHC both potently inhibited thymidine uptake into these tumors, with a mean inhibition by 74 μmol/L genestein of 61.96± 18.96% (±sd inhibition of basal), by 740 μmol/L genestein of 92.65 ± 8.59%, and by 100 μmol/L MDHC of 93.84 ± 3.85%. The 7 pituitary adenomas were all large with suprasellar extension and secreted interleukin-6 in vitro. They included 2 prolactinomas, 1 somatotropinoma, 1 mammosomatropinoma, and 3 clinically nonfunctioning adenomas. Epidermal growth factor stimulated thymidine uptake in 2 of the 3 clinically nonfunctioning adenomas studied, and this stimulation was inhibited by genestein. Both of these tumors released FSH in cell culture and are probably silent gonadotropinomas. The growth stimulatory effect of conditioned medium from human pituitary cell culture on GH3 cells was inhibited by both genestein and MDHC. We conclude that tyrosine kinase activity is crucial for the integrity and growth of pituitary adenomas in culture. Growth factors released by pituitary adenomas potentially may maintain and promote tumor growth by stimulating tyrosine kinase activity.
Influence of Circulating Epinephrine and Norepinephrine on Insulin-Like Growth Factor Binding Protein-1 in Humans
Authors: Fernqvist-Forbes Eva , Hilding Agneta , Ekberg Karin , Brismar Kerstin
Published: January 2014

The aim of the present study was to investigate the influence of circulating epinephrine (Epi) and norepinephrine (Norepi) on serum insulin-like growth factor binding protein-1 (IGFBP-1) concentrations. Healthy men received 0.3 nmol·kg·min Epi iv (n = 6), 0.5 nmol·kg·min Norepi iv (n = 7), or saline (n= 5) during 30 min. Arterial blood samples were obtained before, during, and 120 min after infusion. During the catecholamine infusion arterial Epi and Norepi plasma concentrations reached 6.35 ± 0.53 and 15.65 ± 2.71 nmol/L, respectively, which resulted in significant increases in glucose concentrations. When Epi was infused, IGFBP-1 increased from 45 ± 6 μg/L to 76 ± 10 μg/L (P < 0.05) 60 min after the infusion. Epi was also followed by increases in insulin, C-peptide, and glucagon. Norepi resulted in a slight increase in circulating IGFBP-1 (43 ± 6 to 54 ± 8 nmol/L, NS). The findings suggest that Epi, at plasma concentrations similar to those reached during physical stress, stimulates the production of IGFBP-1 in humans.
The Effect of a Desogestrel-Containing Oral Contraceptive on Glucose Tolerance and Leptin Concentrations in Hyperandrogenic Women*
Authors: Nader Shahla , Riad-Gabriel Maggy G. , Saad Mohammed F.
Published: January 2014

Ovarian hyperandrogenism can be associated with insulin resistance, hyperinsulinemia, glucose intolerance, and obesity. High levels of the lipostatic hormone, leptin, have also been reported in this condition. The purpose of the present study was to examine the effect of an oral contraceptive (OC) of low androgenicity containing desogestrel on glucose tolerance in hyperandrogenic women and the impact of changes in androgenic/estrogenic status on leptin concentrations. Sixteen nondiabetic hyperandrogenic women, aged 29 ± 1 yr with a body mass index (BMI) of 36.8 ± 1.8 kg/m2, underwent an oral glucose tolerance test before and after 6 months of therapy with the OC. Free testosterone decreased and sex hormone-binding globulin increased after therapy (P < 0.001). Glucose tolerance deteriorated significantly, and two women developed diabetes. Body weight, BMI, and leptin did not change significantly. Leptin correlated with BMI before (r = 0.56; P = 0.02) and after (r = 0.51; P = 0.04) treatment, but not with glucose, insulin, total and free testosterone, or sex hormone-binding globulin before or after treatment. In conclusion, 1) glucose tolerance should be monitored in hyperandrogenic women using OC, even those of low androgenicity; and 2) changes in androgenic/estrogenic status had no effect on the leptin concentration, suggesting that its sexual dimorphism is not related to sex steroids.
Mutation Analysis of Glial Cell Line-Derived Neurotrophic Factor, a Ligand for an RET/Coreceptor Complex, in Multiple Endocrine Neoplasia Type 2 and Sporadic Neuroendocrine Tumors
Authors: Marsh Debbie J. , Zheng Zimu , Arnold Andrew , Andrew Scott D. , Learoyd Diana , Frilling Andrea , Komminoth Paul , Neumann Hartmut P.H. , Ponder Bruce A.J. , Rollins Barrett J. , Shapiro Geoffrey I. , Robinson Bruce G. , Mulligan Lois M. , Eng Charis
Published: January 2014

Causative germline missense mutations in the RET proto-oncogene have been associated with over 92% of families with the inherited cancer syndrome multiple endocrine neoplasia type 2 (MEN 2). MEN 2A is characterized primarily by medullary thyroid carcinoma (MTC) and pheochromocytoma, both tumors of neural crest origin. Parathyroid hyperplasia or adenoma is also seen in MEN 2A, but rarely in MEN 2B, which has additional stigmata, including a marfanoid habitus, mucosal neuromas, and ganglioneuromatosis of the gastrointestinal tract. In familial MTC, MTC is the only lesion present. Somatic RET mutations have also been identified in a subset of sporadic MTCs, pheochromocytomas, and rarely, small cell lung cancer, but not in sporadic parathyroid hyperplasias/adenomas or other neuroendocrine tumors. Glial cell line-derived neurotrophic factor (GDNF) and its receptor molecule GDNFR-α, have recently been identified as members of the RET ligand binding complex. Therefore, the genes encoding both GDNF and GDNFR-α are excellent candidates for a role in the pathogenesis of those MEN 2 families and sporadic neuroendocrine tumors without RET mutations. No mutations were found in the coding region of GDNF in DNA samples from 9 RET mutation negative MEN 2 individuals (comprising 6 distinct families), 12 sporadic MTCs, 17 sporadic cases of parathyroid adenoma, and 10 small cell lung cancer cell lines. Therefore, we find no evidence that mutation within the coding regions of GDNF plays a role in the genesis of MEN 2 and sporadic neuroendocrine tumors.
Expression of 5α-Reductase in the Human Temporal Lobe of Children and Adults1
Authors: Stoffel-Wagner Birgit , Watzka Matthias , Steckelbroeck Stephan , Wickert Lucia , Schramm Johannes , Romalo Gabriela , Klingmüller Dietrich , Schweikert Hans-Udo
Published: January 2014

Androgens exert important biological effects on the brain, and 5α-reductase plays a crucial role in androgen metabolism. Therefore, we investigated the expression of the two isozymes of 5α-reductase in the human temporal lobe to determine the predominant isoform and to elucidate the existence of possible sex differences and differences between children and adults. We studied biopsy materials from the temporal lobe of 34 women, 32 men, and 12 children. Quantification of 5α-reductase 1 and 2 messenger ribonucleic acid (mRNA) was achieved by competitive RT-PCR. 5α-Reductase activity was determined in tissue homogenates using [1,2-3H]androstenedione as the substrate. Only 5α-reductase 1 mRNA was expressed in human temporal lobe tissue; 5α-reductase 2 mRNA was not expressed. 5α-Reductase 1 mRNA concentrations did not differ significantly in the cerebral cortex of women [25.9 ± 7.9 arbitrary units (aU); mean ± sem] and men (20.4 ± 2.8 aU) or in the cerebral cortex (23.3 ± 4.4 aU) and the subcortical white matter of adults (32.6 ± 5.6 aU), but they were significantly higher in the cerebral cortex of adults than in that of children (6.4 ± 2.3 aU; P < 0.005). The apparent Km of 5α-reduction did not show significant differences between the two sexes. In conclusion, 5α-reductase 1 mRNA is expressed in the temporal lobe of children and adults, but 5α-reductase 2 mRNA is not. 5α-Reductase 1 mRNA concentrations did not differ significantly in the sexes, but they were significantly higher in specimens of adults than in those of children.
Unchanged Testosterone Production Rates in Growth Hormone-Treated Healthy Men1
Authors: Vierhapper H. , Nowotny P. , Waldhäusl W.
Published: January 2014

The effect of biosynthetic human GH on the production rates of testosterone was determined in healthy men (n = 7) using the stable isotope dilution technique and mass spectrometry. 1α,2α-d-Testosterone (20 μg/h) was infused for 10 h (0800–1800 h). Blood samples obtained at 20-min intervals from 1400–1800 h were pooled during two 2-h periods. Subsequently, each volunteer received a daily dose of biosynthetic human GH (4 IU/day sc) for 7 days. This resulted in a rise in plasma concentrations of somatomedin-C from, basal, 0.67 ± 0.13 U/mL to 1.20± 0.2 U/mL on day 7 (P < 0.0001). Testosterone production rates (basal: 209.9 ± 31.0 μg/h) were unchanged by treatment with GH (day 7: 192.2 ± 30.1 μg/h). In healthy men, short-term treatment with sc GH does not influence endogenous testosterone production rates.
Changes in Thyroid Hormone Levels during Growth Hormone Therapy in Initially Euthyroid Patients: Lack of Need for Thyroxine Supplementation1
Authors: Wyatt David T. , Gesundheit Neil , Sherman Barry
Published: January 2014

The occurrence of central hypothyroidism in previously euthyroid children during GH therapy has been reported with widely varying incidence. We monitored the acute effects on the hypothalamic-pituitary-thyroid axis in 15 euthyroid children with classic GH deficiency during the first year of GH therapy. All were initially euthyroid, as assessed by normal baseline TSH, T4, free T4, and T3 levels and negative antithyroid antibodies. A thyroid profile (T4, free T4 index, T3, rT3, and TSH) was performed at baseline and 1, 3, 6, 9, and 12–15 months after GH therapy began; a TRH stimulation test was performed at baseline and after 1, 3, and 9 months of therapy. By 1 month, there were significant decreases in T4, free T4 index, and rT3, and significant increases in T3 and the T3/T4 ratio. The changes from baseline values were greatest at 1 month, were almost universal for all thyroid values, and showed a gradual return to baseline from 3–12 months. There were no clinical signs of hypothyroidism and no change in baseline or TRH-stimulated TSH levels or in cholesterol levels, and all patients grew at velocities expected for the treatment schedule. There is little evidence for the development of clinically significant hypothyroidism in the great majority of initially euthyroid patients after GH therapy is begun. T4 supplementation is seldom needed in such patients.
The Growth Hormone Response to Hexarelin in Patients with Different Hypothalamic-Pituitary Abnormalities
Authors: Maghnie Mohamed , Spica-Russotto Valeria , Cappa Marco , Autelli Michele , Tinelli Carmine , Civolani Patrizia , Deghenghi Romano , Severi Francesca , Loche Sandro
Published: January 2014

We evaluated the GH-releasing effect of hexarelin (Hex; 2 μg/kg, iv) and GHRH (1 μg/kg, iv) in 18 patients (11 males and 7 females, aged 2.5–20.4 yr) with GH deficiency (GHD) whose hypothalamic pituitary abnormalities had been previously characterized by dynamic magnetic resonance imaging (MRI). Ten patients had isolated GHD, and 8 had multiple pituitary hormone deficiency. All patients were receiving appropriate hormone replacement therapy. Twenty-four prepubertal short normal children (11 boys and 13 girls, aged 5.9–13 yr, body weight within ±10% of ideal weight) served as controls. MRI studies revealed an ectopic posterior pituitary at the infundibular recess in all patients. A residual vascular component of the pituitary stalk was visualized in 8 patients with isolated GHD (group 1), whereas MRI showed the absence of the pituitary stalk (vascular and neural components) in the remaining 10 patients (group 2), of whom 8 had multiple pituitary hormone deficiency and 2 had isolated GHD. In the short normal children, the mean peak GH response to GHRH (24.8 ± 4.4 μg/L) was significantly lower than that observed after Hex treatment (48.1 ± 4.9 μg/L; P < 0.0001). In the GHD patients of group 2, the mean peak GH responses to GHRH (1.4 ± 0.3 μg/L) and Hex (0.9 ± 0.3 μg/L) were similar and markedly low. In the patients of group 1, the GH responses to GHRH (8.7 ± 1.3 μg/L) and Hex (7.0 ± 1.3 μg/L) were also similar, but were significantly higher that those observed in group 2 (P < 0.0001). In the whole group of patients, a significant correlation was found between the GH peaks after Hex and those after GHRH (r = 0.746; P < 0.0001). In this study we have confirmed that the integrity of the hypothalamic pituitary connections is essential for Hex to express its full GH-releasing activity and that Hex is able to stimulate GH secretion in patients with GHD but with a residual vascular component of the pituitary stalk.
Collagen N-Telopeptide Excretion in Men: The Effects of Age and Intrasubject Variability1
Authors: Orwoll Eric S. , Bell Norman H. , Nanes Mark S. , Flessland Karen A. , Pettinger Mary B. , Mallinak Nancy J. S. , Cain Daniel F.
Published: January 2014

Biochemical markers of bone resorption are useful for evaluating metabolic bone diseases. A three-center study was performed in 253 men, 21–86 yr of age, to determine the normal range of urinary N-telopeptide of type I collagen (NTX/creatinine) in a nonfasting, second void, morning specimen, to define the biological variability and to examine the relationship between NTX/creatinine and age. Men with disorders or taking medications known to alter bone turnover, or with a serum creatinine level greater than 2 mg/dL were excluded. Results are expressed as nanomoles of bone collagen equivalents (BCE) per mmol creatinine. In a subset of individuals over age 30 yr, additional second void morning urine specimens were obtained at 2, 3, and 4 days (short term study) and at 2, 3, and 4 months (long term study) after the first specimen. After collection, samples were shipped to one laboratory for analysis. Multiple samples from the same subject were analyzed in separate assays. It was found that urinary NTX/creatinine was significantly higher in 45 men, aged 21–30 yr, than in 206 men, aged 31–86 yr (48 ± 22 vs. 33 ± 15 nmol/L BCE/mmol/L creatinine; P < 0.00001). Values did not otherwise change with age. The range of values in men aged 21–30 yr was 4–92 nmol/L BCE/mmol/L creatinine. The range for men over age 30 yr was 3–63 nmol/L BCE/mmol/L creatinine, essentially the same as that previously reported for premenopausal women. The coefficient of variation was determined in each individual for the short term (n= 36) and long term studies (n = 35) and averaged 18% and 19%, respectively. There was no correlation between short term and long term coefficient of variations. In summary, urinary NTX/creatinine is higher in men aged 21–30 yr than in men over age 30 yr and may reflect continued skeletal maturation. Intrasubject variability of urinary NTX/creatinine in short term and long term studies has been defined for clinical purposes.
Absence of Activating Mutations of the Genes Encoding theα -Subunits of G11 and Gq in Thyroid Neoplasia1
Authors: Ringel Matthew D. , Saji Motoyasu , Schwindinger William F. , Segev Dorry , Zeiger Martha A. , Levine Michael A.
Published: January 2014

Activating mutations of the TSH receptor and α-subunit of Gs (Gαs) that increase adenylyl cyclase activity have been identified in a subset of hyperfunctioning benign thyroid follicular adenomas and, less commonly, in hypofunctioning adenomas and carcinomas. In addition, some thyroid tumors exhibit inappropriate activation of phospholipase C (PLC), a signaling pathway that has been implicated in the growth and dedifferentiation of thyroid cells. We therefore hypothesized that some thyroid tumors might be caused by somatic mutations in the genes encoding the α-chain of Gq or G11 that result in constitutive activation of the PLC pathway. We amplified regions of theα q and α11 genes that encode amino acids, Q209 and R183, and we screened the DNA for mutations by sequence analysis and denaturing gradient gel electrophoresis. No mutations were identified after analysis of DNA from 38 thyroid tumors and 2 poorly differentiated thyroid carcinoma cell lines, including: 13 follicular adenomas, 10 follicular carcinomas, 5 papillary carcinomas, and 10 hyperplastic nodules from multinodular goiters. We conclude that activating mutations of αq and α11 are absent or rare in hypofunctioning thyroid neoplasms and that other mechanisms must explain the elevated PLC activity reported in thyroid carcinoma.
Leptin Levels, β-Cell Function, and Insulin Sensitivity in Families with Congenital and Acquired Generalized Lipoatropic Diabetes1
Authors: Pardini Victor C. , Victória Ivana M. N. , Rocha Selma M. V. , Andrade Danielle G. , Rocha Aline M. , Pieroni Flávia B. , Milagres Gisele , Purisch Saulo , Velho Gilberto
Published: January 2014

Lipoatropic diabetes (LD) designates a group of syndromes characterized by diabetes mellitus with marked insulin resistance and either a localized or generalized absence of adipose tissue. In this study, we evaluated plasma leptin levels in subjects with congenital generalized lipoatropic diabetes (CGLD, n = 11) or acquired generalized lipoatropic diabetes (AGLD, n = 11), and assessed correlations between leptin levels and estimations of insulin secretion and insulin sensitivity using homeostasis model assessment (HOMA). Leptin levels were 0.86 ± 0.32, 1.76 ± 0.78, and 6.9 ± 4.4 ng/mL in subjects with CGLD, AGLD, and controls (n = 19), respectively (ANOVA P < 0.0001). Specific insulin levels were 154 ± 172, 177 ± 137 and 43 ± 22 pmol/L, respectively (P < 0.0001). Insulin sensitivity was significantly decreased in both groups with LD (P< 0.0001), whereas HOMA β-cell function was not significantly different when compared with controls. Leptin levels were significantly correlated with body mass index, insulin levels, and HOMA β-cell function, and inversely correlated with insulin sensitivity in control subjects but not in subjects with generalized LD. In conclusion, decreased leptin levels were observed in subjects with generalized LD, with a trend towards lower levels in the acquired than in the congenital form (P = 0.06). The temporal relationship between the decrease in leptin levels and the development of lipoatrophy should be investigated in at-risk young relatives of subjects with the acquired forms to assess the usefulness of leptin levels as a marker of lipoatrophy.
Cytokines and Thyroid Epithelial Integrity: Interleukin-1α Induces Dissociation of the Junctional Complex and Paracellular Leakage in Filter-Cultured Human Thyrocytes1
Authors: Nilsson Mikael , Husmark Johanna , Björkman Ulla , Ericson Lars E.
Published: January 2014

Locally produced proinflammatory cytokines are likely to play a pathophysiological role in autoimmune thyroid disease. An important feature of the thyroid, not previously considered in cytokine actions, is the barrier created by the follicular epithelium, which secludes two lumenal autoantigens [thyroglobulin (Tg) and thyroperoxidase] from the extrafollicular space. We examined the influence of recombinant cytokines on the barrier function of human thyrocytes cultured as a tight and polarized monolayer in bicameral chambers. Whereas interleukin (IL)-6 (100 U/mL), interferon-γ (100 U/mL), tumor necrosis factor-α (10 ng/mL), and transforming growth factor-β1 (10 ng/mL) had no effects, exposure to IL-1α for 24–48 h reduced the transepithelial resistance from >1000 to <50 Ω × cm2 and increased the paracellular flux of [3H]inulin and exogeneous 125I-Tg. This response to IL-1α, which was dose dependent (1–1000 U/mL) and reversible, was accompanied by dramatic morphological changes of the epithelial junction complex, including aberrant localization of the tight junction protein zonula occludens-1. At the same time, IL-1α decreased the apical secretion of endogeneous Tg and stimulated the basolateral release of a novel high-molecular-mass protein. We conclude that IL-1α reduces the thyroid epithelial barrier without signs of general cytotoxicity. The observation suggests a mechanism by which IL-1α may promote the exposure of hidden autoantigens to the immune system in thyroid autoimmunity.
Mutation/Polymorphism Scanning of Glucose-6-Phosphatase Gene Promoter in Noninsulin-Dependent Diabetes Mellitus Patients1
Authors: Yoshiuchi Issei , Shingu Ryosuke , Nakajima Hiromu , Hamaguchi Tomoya , Horikawa Yukio , Yamasaki Tomoyuki , Oue Takanori , Ono Akira , Miyagawa Jun-ichiro , Namba Mitsuyoshi , Hanafusa Toshiaki , Matsuzawa Yuji
Published: January 2014

Glucose-6-phosphatase (G6Pase) catalyzes the rate-limiting step of gluconeogenesis, and hepatic G6Pase activity is increased in diabetes. We have cloned and analyzed the human G6Pase gene promoter region and identified putative regulatory sequences for insulin, cAMP, glucocorticoid, and hepatocyte nuclear factors. The promoter region of the G6Pase gene was analyzed in 154 noninsulin-dependent diabetes mellitus patients and 90 control subjects by PCR-single strand conformation polymorphism and direct sequencing methods. Polymorphisms were not found in any subjects. The results suggested that in noninsulin-dependent diabetic patients, the major cause of the hepatic glucose overproduction was not attributed to dysregulation of the G6Pase gene due to mutation/polymorphism of its promoter region.