bluuebunny/crossref_metadata_2025 huggingface dataset:
The Thyroid Hormone Receptor-β Gene Mutation R383H Is Associated with Isolated Central Resistance to Thyroid Hormone1
Authors: Safer J. D. , O’Connor M. G. , Colan S. D. , Srinivasan S. , Tollin S. R. , Wondisford F. E.
Published: January 2014

Resistance to thyroid hormone (RTH) action is due to mutations in theβ -isoform of the thyroid hormone receptor (TR-β). RTH patients display inappropriate central secretion of TRH from the hypothalamus and of TSH from the anterior pituitary despite elevated levels of thyroid hormone (T4 and T3). RTH mutations cluster in three hot spots in the C-terminal portion of the TR-β. Most individuals with TR-β mutations have generalized resistance to thyroid hormone, where most tissues in the body are hyporesponsive to thyroid hormone. The affected individuals are clinically euthyroid or even hypothyroid depending on the severity of the mutation. Whether TR-β mutations cause a selective form of RTH that only leads to central thyroid hormone resistance is debated. Here, we describe an individual with striking peripheral sensitivity to graded T3 administration. The subject was enrolled in a protocol in which she received three escalating T3 doses over a 13-day period. Indexes of central and peripheral thyroid hormone action were measured at baseline and at each T3 dose. Although the patient’s resting pulse rose only 11% in response to T3, her serum ferritin, alanine aminotransferase, aspartate transaminase, and lactate dehydrogenase rose 320%, 117%, 121%, and 30%, respectively. In addition, her serum cholesterol, creatinine phosphokinase, and deep tendon reflex relaxation time fell (25%, 36%, and 36%, respectively). Centrally, the patient was sufficiently resistant to T3 that her serum TSH was not suppressed with 200 μg T3, orally, daily for 4 days. The patient’s C-terminal TR exons were sequenced revealing the mutation R383H in a region not otherwise known to harbor TR-β mutations. Our clinical evaluation presented here represents the most thorough documentation to date of the central thyroid hormone resistance phenotype in an individual with an identified TR-β mutation.
Responses of Markers of Bone and Collagen Turnover to Exercise, Growth Hormone (GH) Administration, and GH Withdrawal in Trained Adult Males1
Authors: Wallace Jennifer D. , Cuneo Ross C. , Lundberg Per Arne , Rosén Thord , Jørgensen Jens Otto Lunde , Longobardi Salvatore , Keay Nicola , Sacca Luigi , Christiansen Jens Sandahl , Bengtsson Bengt-Åke , Sönksen Peter H.
Published: January 2014

To examine the interactions between acute exercise and GH on markers of bone and collagen turnover and to assess the potential for detecting GH abuse in athletes using these markers, we studied 17 aerobically trained males (age, 26.9 ± 1.5 yr). Sequential studies of exercise, GH administration, and GH withdrawal were undertaken. A randomized, controlled study of rest vs. exercise showed that exercise did not change serum osteocalcin; other markers of formation increased transiently (each P < 0.001): bone-specific alkaline phosphatase (+16.1%), carboxyterminal propeptide of type I procollagen (+14.1%), and procollagen III N-terminal extension peptide (+5.0%). The carboxyterminal cross-linked telopeptide of type I collagen, a bone resorption marker, increased 9.7% (P = 0.018) in response to exercise. A randomized, double blind, placebo-controlled, parallel study of recombinant human GH treatment (0.15 IU/kg·day) for 1 week increased serum osteocalcin (net increase preexercise, +10.0%; P = 0.017), carboxyterminal propeptide of type I procollagen (+17.6%; P = 0.002), procollagen III N-terminal extension peptide (+48.4%; P = 0.001), and carboxyterminal cross-linked telopeptide of type I collagen (53.3%; P = 0.009). Disappearance half-times after cessation of recombinant human GH for pre- and postexercise markers ranged from 248–770 h. We conclude 1) endurance exercise transiently activates bone and collagen turnover; 2) brief GH administration results in similar but quantitatively greater augmentation; and 3) these data will assist in designing a GH detection strategy.
Synergistic Effect of Adrenal Steroids and Angiotensin II on Plasminogen Activator Inhibitor-1 Production1
Authors: Brown Nancy J. , Kim Kyung-Soo , Chen Yan-Qun , Blevins Lewis S. , Nadeau John H. , Meranze Steven G. , Vaughan Douglas E.
Published: January 2014

Recent data suggest an interaction between the renin-angiotensin-aldosterone system and fibrinolysis. Although previous work has focused on the effect of angiotensin II (Ang II) on plasminogen activator inhibitor (PAI-1) expression, the present study tests the hypothesis that aldosterone contributes to the regulation of PAI-1 expression. To test this hypothesis in vitro, luciferase reporter constructs containing the human PAI-1 promoter were transfected into rat aortic smooth muscle cells. Exposure of the cells to 100 nmol/L Ang II resulted in a 3-fold increase in luciferase activity. Neither 1 μmol/L dexamethasone nor 1 μmol/L aldosterone alone increased PAI-1 expression. However, both dexamethasone and aldosterone enhanced the effect of Ang II in a dose-dependent manner. This effect was abolished by mutation in the region of a putative glucocorticoid-responsive element. A similar interactive effect of Ang II and aldosterone was observed in cultured human umbilical vein endothelial cells. The time course of the effect of aldosterone on Ang II-induced PAI-1 expression was consistent with a classical mineralocorticoid receptor mechanism, and the effect of aldosterone on PAI-1 synthesis was attenuated by spironolactone. To determine whether aldosterone affected PAI-1 expression in vivo, we measured local venous PAI-1 antigen concentrations in six patients with primary hyperaldosteronism undergoing selective adrenal vein sampling. PAI-1 antigen, but not tissue plasminogen activator antigen, concentrations were significantly higher in adrenal venous blood than in peripheral venous blood. Taken together, these data support the hypothesis that aldosterone modulates the effect of Ang II on PAI-1 expression in vitro and in vivo in humans.
Direct Measurement of Pulsatile Insulin Secretion from the Portal Vein in Human Subjects1
Authors: Song Soon H. , McIntyre Susan S. , Shah Hasnain , Veldhuis Johannes D. , Hayes Peter C. , Butler Peter C.
Published: January 2014

Insulin is secreted in a high frequency pulsatile manner. These pulses are delivered directly into the portal vein and then undergo extraction and dilution before delivery into the systemic circulation. The reported frequency of these insulin pulses estimated in peripheral blood varies from an interpulse interval of 4–20 min. We postulated that this discrepancy is due to the attenuation of the pulse signal in the systemic circulation vs. the portal circulation. In the present study we measured pulsatile insulin release directly in the portal circulation of human subjects who had indwelling transjugular intrahepatic portasystemic stent shunts (TIPSS) to decompress portal hypertension. We quantitated pulsatile insulin secretion in both the overnight fasted state (fasting) and during a hyperglycemic clamp (8 mmol/L). Direct portal vein sampling established that pulsatile insulin secretion in humans has an interval (periodicity) of approximately 5 min. The amplitude (and mass) of the insulin concentration oscillations observed in the portal vein was approximately 5-fold greater than that observed in the arterialized vein and was similar to that observed in the dog. Increased insulin release during hyperglycemia was achieved through amplification of the insulin pulse mass. In conclusion, direct portal vein sampling in humans revealed that the interpulse interval of insulin pulses in humans is about 5 min, and this frequency is also observed when sampling from the systemic circulation using a highly specific insulin assay and 1-min sampling, but is about 4-fold greater than the frequency observed at this site using single site RIAs. We confirm that enhanced insulin release in response to hyperglycemia is achieved by amplification of these high frequency pulses.
Type I Hyperlipoproteinemia Due to a Novel Loss of Function Mutation of Lipoprotein Lipase, Cys239→Trp, Associated with Recurrent Severe Pancreatitis
Authors: Hoffmann Michael M. , Jacob Stephan , Luft Dieter , Schmülling Reinhold-M. , Rett Kristian , März Winfried , Häring Hans-Ulrich , Matthaei Stephan
Published: January 2014

Lipoprotein lipase (LPL) is the major enzyme responsible for the hydrolysis of triglyceride-rich lipoproteins in plasma. The purpose of this study was to examine the molecular pathogenesis of type I hyperlipoproteinemia in a patient suffering from recurrent severe pancreatitis. Apolipoprotein (apo) CII concentration was normal as well as apo CII-activated LPL in an in vitro assay. In postheparin plasma neither LPL mass nor activity was detectable, whereas hepatic lipase activity was normal. Direct sequencing of all 10 exons of the LPL gene revealed that the patient was homozygous for a hitherto unknown mutation in exon 6, Cys239→Trp. The mutation prevents the formation of the second disulfide bridge of LPL, which is an essential part of the lid covering the catalytic center. Consequently, misfolded LPL is rapidly degraded within the cells, causing the absence of LPL immunoreactive protein in the plasma of this patient. In conclusion, we have identified a novel loss of function mutation in the LPL gene (Cys239→Trp) of a patient with type I hyperlipoproteinemia suffering from severe recurrent pancreatitis. After initiation of heparin therapy (10,000 U/day sc), the patient experienced no more episodes of pancreatitis, although heparin therapy did not affect serum triglyceride levels.
Response of Leucine Metabolism to Hyperinsulinemia in Hypothyroid Patients before and after Thyroxine Replacement1
Authors: Rochon Cecile , Tauveron Igor , Dejax Catherine , Benoit Patrick , Capitan Pierre , Bayle Gerard , Prugnaud Jacques , Fabricio Andrea , Berry Christiane , Champredon Claude , Thieblot Philippe , Grizard Jean
Published: January 2014

We have investigated the effect of hypothyroidism and insulin on protein metabolism in humans. Six hypothyroid patients were studied in a postabsorptive state before and after 5 months of regular treatment for hypothyroidism (153 ± 17 μg/day of l-T4). The effect of insulin was assessed under hyperinsulinemic euglycemic and eukalemic conditions. Insulin was infused for 140 min at 0.0063 ± 0.0002 nmol/kg·min. An amino acid infusion was used to blunt insulin-induced hypoaminoacidemia. Whole body protein turnover was measured using l-[1-13C] leucine. When compared to L-T4-induced subclinical thyrotoxic state, hypothyroidism induced a significant decrease (P < 0.05) in leucine endogenous appearance rate (a reflection of proteolysis; 0.89 ± 0.09 vs. 1.33 ± 0.05 μmol/kg·min), oxidation (0.19 ± 0.02 vs. 0.25 ± 0.03 μmol/kg·min), and nonoxidative disposal (a reflection of protein synthesis; 0.87± 0.11 vs. 1.30 ± 0.05 μmol/kg·min). Insulin lowered proteolysis during both the subclinical thyrotoxic and hypothyroid states. Hypothyroidism impaired the antiproteolytic effects of insulin. Thyroid hormones are, therefore, essential for the normal antiproteolytic action of insulin.
Heritability of Prostate-Specific Antigen and Relationship with Zonal Prostate Volumes in Aging Twins*
Authors: Bansal Aruna , Murray Darrell K. , Wu James T. , Stephenson Robert A. , Middleton Richard G. , Meikle A. Wayne
Published: January 2014

Both benign prostatic hyperplasia and prostate-specific antigen (PSA) have been shown to increase with age and with prostate volume in men, but the influence of heredity on these relationships is not completely understood. This study has two aims: 1) to investigate the inter-relationships of age, PSA, and various zonal measurements in the prostate; and 2) to assess the impact of heritable influences on total PSA. Eighty-four monozygotic twin pairs and 83 dizygotic twin pairs were studied, and serum total PSA, free PSA, and PSA-∝1-antichymotrypsin were measured. Their prostate volumes [total (TV), transition zone (TZ), and peripheral zone) were quantitated using transrectal ultrasound.

Total PSA is significantly correlated with all zonal prostate measurements (TZ, peripheral zone, TV, and TZ/TV) and with age. When linear regression was applied, only age and TZ were retained in the final model. The proportion of variability in total PSA explained by these two factors, however, is below 24%. In contrast, estimates of heritability show that approximately 45% of the variability in total PSA can be explained by inherited factors. Whereas age and TZ are linearly related to total PSA, their influence is much less than that of familial and genetic factors. It is uncertain whether these factors predispose also to prostate cancer or if they are independent of those, whether they confound the accuracy of using total serum PSA level as a diagnostic tool.
Corticotropin-Releasing Hormone Gene Expression in Primary Placental Cells Is Modulated by Cyclic Adenosine 3′,5′-Monophosphate*
Authors: Cheng You-Hong , Nicholson Richard C. , King Bruce , Chan Eng-Cheng , Fitter John T. , Smith Roger
Published: January 2014

CRH, the principal neuropeptide regulator of pituitary ACTH secretion, is also expressed in placenta. Placental CRH has been linked to the process of human parturition. However, the mechanisms regulating transcription of the CRH gene in placenta remain unclear. cAMP signaling pathways play important roles in regulating the expression of a diverse range of endocrine genes in the placenta. Therefore, we have explored the effect of cAMP on CRH promoter activity in primary cultures of human placental cells. Both forskolin and 8-bromo-cAMP, activators of protein kinase A, can increase CRH promoter activity 5-fold in transiently transfected human primary placental cells, in a manner that parallels the increase in endogenous CRH peptide. Maximal stimulation of CRH promoter activity occurs at 500 μmol/L 8-bromo-cAMP and 10 μmol/L forskolin. Electrophoretic mobility shift assay and mutation analysis combined with transient transfection demonstrate that in placental cells cAMP stimulates CRH gene expression through a cAMP regulatory element in the proximal CRH promoter region and involves a placental nuclear protein interacting specifically with the cAMP regulatory element.
Serum Withdrawal-Induced Apoptosis in Thyroid Cells Is Caused by Loss of Fibronectin-Integrin Interaction*
Authors: Di Matola Tiziana , Mueller Frank , Fenzi Gianfranco , Rossi Guido , Bifulco Maurizio , Marzano Luigi Antonio , Vitale Mario
Published: January 2014

In some cell types, including a fetal thyroid cell line, denial of adhesion to extracellular matrix induces a type of apoptosis called anoikis. Serum withdrawal in dog and transformed rat thyroid cells also induces programmed cell death. Because serum can stimulate cells to produce some components of the extracellular matrix, it was of interest to determine the role of the matrix in the apoptosis induced by serum withdrawal in normal human thyroid cells in primary culture. The present report demonstrates that thyroid cells selectively produce and deposit insoluble fibronectin (FN) only when stimulated by serum. Adhesion in the presence of serum is dependent upon integrin-FN interaction. Serum withdrawal determines a degradation of the insoluble FN deposited and a detachment of the cells from the plates. In these conditions, cells undergo anoikis, demonstrated by DNA fragmentation and annexin V staining. Apoptosis was prevented by exogenous FN immobilized onto the plates. These results indicate that serum withdrawal induces apoptosis in human thyroid cells, determining FN degradation and loss of cell-matrix adhesion.
Prognostic Value of[ 18F]Fluorodeoxyglucose Positron Emission Tomographic Scanning in Patients with Thyroid Cancer*
Authors: Wang Weiping , Larson Steven M. , Fazzari Melissa , Tickoo Satish K. , Kolbert Katherine , Sgouros George , Yeung Henry , Macapinlac Homer , Rosai Juan , Robbins Richard J.
Published: January 2014

Poorly differentiated thyroid cancer lesions often lose the ability to concentrate radioactive [131I]iodine (RAI) and exhibit increased metabolic activity, as evidenced by enhanced glucose uptake. We incorporated [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) scanning into the routine follow-up of a cohort of thyroid cancer patients undergoing annual evaluations. One hundred and twenty-five patients who had previous thyroidectomies were included. They had diagnostic RAI whole body scans, serum thyroglobulin measurements, and additional imaging studies as clinically indicated. During 41 months of follow-up, 14 patients died. Univariate analysis demonstrated that survival was reduced in those with age over 45 yr, distant metastases, PET positivity, high rates of FDG uptake, and high volume of the FDG-avid disease (>125 mL). Survival did not correlate with gender, RAI uptake, initial histology, or grade. Multivariate analysis demonstrated that the single strongest predictor of survival was the volume of FDG-avid disease. The 3-yr survival probability of patients with FDG volumes of 125 mL or less was 0.96 (95% confidence interval, 0.91, 1.0) compared with 0.18 (95% confidence interval, 0.04, 0.85) in patients with FDG volume greater than 125 mL. Only 1 death (of leukemia) occurred in the PET-negative group (n = 66). Of the 10 patients with distant metastases and negative PET scans, all were alive and well. Patients over 45 yr with distant metastases that concentrate FDG are at the highest risk. Once distant metastases are discovered in patients with differentiated thyroid carcinoma, FDG-PET can identify high and low risk subsets. Subjects with a FDG volume greater than 125 mL have significantly reduced short term survival.
Five Patients with Biochemical and/or Clinical Generalized Glucocorticoid Resistance without Alterations in the Glucocorticoid Receptor Gene*
Authors: Huizenga Nannette A. T. M. , de Lange Pieter , Koper Jan W. , de Herder Wouter W. , Abs Roger , Kasteren Jan H. L. M. v. , de Jong Frank H. , Lamberts Steven W. J.
Published: January 2014

Cortisol resistance (CR) is a rare disease characterized by a generalized reduced sensitivity of end-organs to the actions of glucocorticoids (GCs). GC effects are mediated by the GC receptor (GR). The molecular alterations in CR described thus far were located in the hormone-binding domain of the GR gene. Recent reports of a considerable prevalence of abnormalities in the GR in patients attending the endocrine clinic prompted us to carry out further investigations with respect to GR protein and GR gene in patients attending the endocrine clinic for a broad spectrum of complaints and biochemical evidence suggesting a CR.

In the present study, we describe five patients with biochemical and clinical CR. All patients showed a diurnal rhythm of serum cortisol concentrations (albeit at a high level), an insufficient suppression of serum cortisol concentration in reaction to 1 mg dexamethasone (DEX), and variable degrees of androgen overproduction, in the absence of clinical signs and symptoms of Cushing’s syndrome. Three of the four female patients presented with complaints of androgen overproduction, two of them in combination with fatigue. The other female patient had severe steroid-resistant asthma. The only male patient and his son were asymptomatic.

In four patients, we investigated receptor protein characteristics on mononuclear leukocytes in a whole cell DEX binding assay and studied the ability of DEX to inhibit mitogen-induced cell proliferation in mononuclear leukocytes in vitro. In all patients investigated, we found alterations in receptor number or ligand affinity and/or the ability of DEX to inhibit mitogen-induced cell proliferation.

To investigate the molecular defects leading to the clinical and biochemical pictures in these patients, we screened the GR gene using PCR/single-strand conformational polymorphism/sequence analysis. No GR gene alterations were found in these patients.

In conclusion, the five patients described had clinical and biochemical evidence of CR, but no abnormalities were demonstrated in the GR gene.

Probably, as yet undefined alterations somewhere in the cascade of events starting with ligand binding to the GR protein, and finally resulting in the regulation of the expression of GC responsive genes, or postreceptor defects or interactions with other nuclear factors form the pathophysiologic basis of CR in these patients.
Estrogen Suppression in Males: Metabolic Effects1
Authors: Mauras Nelly , O’Brien Kimberly O. , Klein Karen Oerter , Hayes Valerie
Published: January 2014

We have shown that testosterone (T) deficiency per se is associated with marked catabolic effects on protein, calcium metabolism, and body composition in men independent of changes in GH or insulin-like growth factor I production. It is not clear, however, whether estrogens have a major role in whole body anabolism in males. We investigated the metabolic effects of selective estrogen suppression in the male using a potent aromatase inhibitor, Arimidex (Anastrozole). First, a dose-response study of 12 males (mean age, 16.1 ± 0.3 yr) was conducted, and blood withdrawn at baseline and after 10 days of oral Arimidex given as two different doses (either 0.5 or 1 mg) in random order with a 14-day washout in between. A sensitive estradiol (E2) assay showed an approximately 50% decrease in E2 concentrations with either of the two doses; hence, a 1-mg dose was selected for other studies. Subsequently, eight males (aged 15–22 yr; four adults and four late pubertal) had isotopic infusions of [13C]leucine and 42Ca/44Ca, indirect calorimetry, dual energy x-ray absorptiometry, isokinetic dynamometry, and growth factors measurements performed before and after 10 weeks of daily doses of Arimidex. Contrary to the effects of T withdrawal, there were no significant changes in body composition (body mass index, fat mass, and fat-free mass) after estrogen suppression or in rates of protein synthesis or degradation; carbohydrate, lipid, or protein oxidation; muscle strength; calcium kinetics; or bone growth factors concentrations. However, E2 concentrations decreased 48% (P = 0.006), with no significant change in mean and peak GH concentrations, but with an 18% decrease in plasma insulin-like growth factor I concentrations. There was a 58% increase in serum T (P = 0.0001), sex hormone-binding globulin did not change, whereas LH and FSH concentrations increased (P < 0.02, both). Serum bone markers, osteocalcin and bone alkaline phosphatase concentrations, and rates of bone calcium deposition and resorption did not change. In conclusion, these data suggest that in the male 1) estrogens do not contribute significantly to the changes in body composition and protein synthesis observed with changing androgen levels; 2) estrogen is a main regulator of the gonadal-pituitary feedback for the gonadotropin axis; and 3) this level of aromatase inhibition does not negatively impact either kinetically measured rates of bone calcium turnover or indirect markers of bone calcium turnover, at least in the short term. Further studies will provide valuable information on whether timed aromatase inhibition can be useful in increasing the height potential of pubertal boys with profound growth retardation without the confounding negative effects of gonadal androgen suppression.
Insulin-Like Growth Factor I Is Not a Useful Marker of Prostate Cancer in Men with Elevated Levels of Prostate-Specific Antigen1
Authors: Finne Patrik , Auvinen Anssi , Koistinen Hannu , Zhang Wan-Ming , Määttänen Liisa , Rannikko Sakari , Tammela Teuvo , Seppälä Markku , Hakama Matti , Stenman Ulf-Håkan
Published: January 2014

High serum levels of insulin-like growth factor I (IGF-I) and low levels of IGF-binding protein-3 (IGFBP-3) have been shown to correlate with increased prostate cancer risk. To evaluate this, IGF-I, IGFBP-3, and prostate-specific antigen (PSA) were measured in serum from 665 consecutive men (179 with prostate cancer), aged 55–67 yr, with elevated serum prostate-specific antigen (PSA; ≥4 μg/L) in a screening trial. Men in the highest quartile of IGF-I levels had an odds ratio (OR) for prostate cancer of 0.50 [95% confidence interval (CI) 0.26–0.97] when adjusting for serum IGFBP-3. IGFBP-3 itself was not significantly associated with prostate cancer risk (OR, 1.24; 95% CI, 0.68–2.24). Prostate volume was larger in men without than in those with prostate cancer (P < 0.001), and after adjustment for prostate volume, the negative association between serum IGF-I and prostate cancer risk was no longer significant (OR, 0.57; 95% CI, 0.28–1.16). In screen-positive men with elevated serum PSA, serum IGF-I is not a useful diagnostic test for prostate cancer, but it may be associated with benign prostatic hyperplasia and enlargement.
Progesterone Receptor Isoform A But Not B Is Expressed in Endometriosis1
Authors: Attia George R. , Zeitoun Khaled , Edwards Dean , Johns Alan , Carr Bruce R. , Bulun Serdar E.
Published: January 2014

We previously demonstrated that 17β hydroxysteroid dehydrogenase type 2, the enzyme that inactivates estradiol to estrone, is expressed in luteal eutopic endometrium in response to progesterone but not in simultaneously biopsied peritoneal endometriotic tissue. This molecular evidence of progesterone resistance, together with the clinical observation of resistance of endometriosis to treatment with progestins, led us to determine the levels of progesterone receptor (PR) isoforms PR-A and PR-B in eutopic endometrial and extra-ovarian endometriotic tissues. It was proposed that progesterone action on target genes is mediated primarily by homodimers of PR-B, whereas the truncated variant PR-A acts as a repressor of PR-B function. Immunoprecipitation, followed by Western blot analysis, was performed to detect bands specific for PR-A and PR-B in paired samples of endometriotic and eutopic endometrial tissues simultaneously biopsed from 18 women undergoing laparoscopy during various phases of the menstrual cycle. PR-B was present in 17 of 18 eutopic endometrial samples, and its level increased in the preovulatory phase, as expected, whereas PR-A was detected in all samples (n = 18) with a similar, but less prominent, cyclic variation in its levels. In endometriotic samples, however, no detectable PR-B could be demonstrated, whereas PR-A was detected in all samples (n = 18), albeit in much lower levels and without any cyclic variation in contrast with the eutopic endometrium. Levels of PR-A and PR-B in endometriotic and eutopic endometrial tissues were determined and compared after normalization to total protein and estrogen receptor-α levels. Using RNase protection assay, we also demonstrated indirectly that only PR-A transcripts were present in endometriotic tissue samples (n = 8), whereas both PR-A and PR-B transcripts were readily detectable in all eutopic endometrial samples (n = 8). This was indicative that failure to detect PR-B protein in endometriotic tissues is due to the absence of PR-B transcripts. We conclude that progesterone resistance in endometriotic tissue from laboratory and clinical observations may be accounted for by the presence of the inhibitory PR isoform PR-A and the absence of the stimulatory isoform PR-B.
A Gonadotropin-Releasing Hormone-Responsive Phosphatase Hydrolyses Lysophosphatidic Acid within the Plasma Membrane of Ovarian Cancer Cells
Authors: Imai Atsushi , Furui Tatsuro , Tamaya Teruhiko , Mills Gordon B.
Published: January 2014

Lysophosphatidic acid (LPA) mediates pleomorphic effects on multiple cell lineages, including an increased proliferative response of ovarian cancer cells both in vitro and in vivo, at least in part through the novel expression of LPA receptors. Thus, LPA hydrolysis is necessary to limit the duration of LPA’s action on multiple cell types, including ovarian cancer cells. We determined the principal mechanism of LPA hydrolysis by ovarian cancer cells and its regulation by GnRH, which is known to have antiproliferative actions on ovarian carcinomas. LPA-hydrolyzing activity in cell membranes of ovarian cancer specimens was assessed by measuring the conversion of exogenous [3H-oleoyl]LPA to [3H]oleic acid or mono[3H-oleoyl]glycerol. Approximately 98% of LPA hydrolysis could be accounted for by the dephosphorylation of LPA to yield monoglyceride, with the deacylation reaction accounting for less than 1% of LPA hydrolysis. The phosphatase activity in the plasma membrane ovarian cancer cells was approximately 2.5- and 8-fold higher than those in microsome and homogenate fractions, respectively. The membrane phosphatase was Mg2+ independent and insensitive to inhibition by N-ethylmaleimide, characteristics suggestive of phosphatidic acid phosphatase activity. Incubation of membranes from GnRH receptor-positive ovarian cancer specimens with the GnRH agonist, buserelin, induced a dose-dependent increase in LPA phosphatase activity, with a half-maximal effect occurring with 30 nmol/L buserelin. The stimulatory action of buserelin could be neutralized by displacement of GnRH from its receptor by the GnRH antagonist, antide. The plasma membranes from GnRH receptor-negative ovarian cancer specimens did not respond to GnRH stimulation. LPA phosphatase activity was also increased when the ovarian cancer cell line Caov-3 was exposed to GnRH agonist in intact cells before assay of cell membranes. These data demonstrate that LPA is hydrolyzed in the plasma membrane of ovarian cancer cells by the action of LPA phosphatase and provide initial evidence for functional coupling of LPA phosphatase to GnRH receptor occupancy.
Insulin-Like Growth Factor I and the Development of Colorectal Neoplasia in Acromegaly*
Authors: Jenkins P. J. , Frajese V. , Jones A-M. , Camacho-Hubner C. , Lowe D. G. , Fairclough P. D. , Chew S. L. , Grossman A. B. , Monson J. P. , Besser G. M.
Published: January 2014

Patients with acromegaly are at increased risk of colorectal neoplasia and, by analogy with high-risk nonacromegalic patients, may require regular colonoscopic screening. However, it is unknown whether the risk is equal in all patients or whether some should be regarded as carrying a particularly high risk. The aims of this study were: 1) to establish the natural history of colorectal neoplasia in acromegaly; 2) to establish which patients are at increased risk of developing neoplasia; and 3) to elucidate the influence of insulin-like growth factor I (IGF-I) in adenoma formation. A prospective colonoscopic evaluation of the development of new premalignant adenomas in the colon was performed in 66 patients with biochemically proven acromegaly who had previously undergone colonoscopic screening and removal of all visible polyps. Twenty-five patients (38%) had a total of 37 polyps detected at the second colonoscopy: nine (14%) had at least one adenoma, and 18 (27%) had one or more hyperplastic polyps (2 patients had both). The development of new adenomas, but not hyperplastic polyps, was associated both with elevated serum IGF-I (P < 0.005) and, to a lesser extent, with a previous adenoma at the original colonoscopy (P < 0.07). In summary, patients with acromegaly and in whom serum IGF-I remains elevated and/or who have had a previous adenoma should be regarded as having an especially high risk for the development of subsequent colorectal neoplasia. Serum IGF-I seems to be implicated in the development of colorectal neoplasia in acromegaly, although the exact mechanisms remain uncertain.
Dizygotic Twinning Is Not Linked to Variation at the α -Inhibin Locus on Human Chromosome 2*
Authors: Montgomery Grant W. , Duffy David L. , Hall Jeff , Haddon Barbara R. , Kudo Masataka , Mcgee Elizabeth A. , Palmer James S. , Hsueh Aaron J. , Boomsma Dorret I. , Martin Nicholas G.
Published: January 2014

Natural multiple pregnancy in women leading to dizygotic (DZ) twins is familial and varies across racial groups, suggesting a genetic predisposition. Mothers of DZ twins have a higher incidence of spontaneous multiple ovulation and elevated FSH concentrations. FSH release is controlled by feedback of inhibin peptides from the ovary, and immunization against inhibin α-subunit results in an increased ovulation rate in animals. The inhibin α-subunit is therefore a candidate gene for mutations that may increase the frequency of DZ twinning. Restriction digests of a PCR product from exon 1 with the enzyme SpeI detects a C/T polymorphism at bp 128 with two alleles of 447 and 323/124 bp. The polymorphism was typed in 1125 individuals from 326 pedigrees with 717 mothers of spontaneous DZ twins. The α-inhibin locus mapped within 3 centimorgans of D2S164, and linkage with DZ twinning was excluded [decimal log odds ratio (LOD) score, −2.81 at θ = 0]. There was complete exclusion of linkage (LOD, less than −2) of a gene conferring relative risk 1.8 (λs, >1.8) across the chromosome, except at the p-terminus region and a small peak (maximum LOD score, 0.6) in the region of D2S151-D2S326. Analysis using either recessive or dominant models excluded linkage with DZ twinning in this population (LOD score, less than −2.5) across chromosome 2. We conclude that dizygotic twinning is not linked to variation in the α-inhibin locus. The results also suggest that mutations in other candidates on chromosome 2, including the receptor for FSH and the βB-inhibin subunit (INHBB) cannot be major contributors to risk for DZ twinning.
Androgen Receptor Gene CAG Trinucleotide Repeats in Anovulatory Infertility and Polycystic Ovaries
Authors: Mifsud Amparo , Ramirez Sylvia , Yong E. L.
Published: January 2014

Hyperandrogenism is currently thought to be central to the pathogenesis of polycystic ovarian syndrome (PCOS), a common endocrine disorder in premenopausal women characterized by irregular menstruation and anovulatory infertility. Although hyperandrogenism is characteristic, some women with PCOS have normal serum androgen levels. All androgens act through the X-linked androgen receptor (AR), the N-terminal domain of which contains a polyglutamine tract encoded by a highly polymorphic CAG trinucleotide repeat tract. Recently, variations in this CAG microsatellite tract, while remaining within the normal polymorphic range (11–38 CAGs), have been inversely correlated with receptor activity. Thus, short tracts are associated with high intrinsic AR activity and increased severity and earlier age of onset of the androgen-regulated tumor prostate cancer, whereas longer CAG tracts are associated with low AR activity and oligospermic infertility. To investigate the role of the CAG repeat tract in PCOS, we measured its length in 91 patients with ultrasound diagnosis of polycystic ovaries, irregular menstrual cycles, and anovulatory infertility and compared them to 112 control subjects of proven fertility with regular menses. Fluorescent-labeled DNA fragments containing the CAG repeat tract were amplified from leucocytic DNA, and their lengths were compared with internal size markers on an automated DNA Sequencer. There were no differences in the mean CAG length between patients and controls when both alleles were considered together or separately. Because there is a subset of PCOS patients whose serum androgens are normal, we compared differences in CAG length between patients whose serum testosterone (T) levels were below the normal laboratory mean, to those that were higher. There was a trend for a lower mean CAG biallelic length among anovulatory patients with T less than 1.73 nmol/L compared with those whose T was more than 1.73 nmol/L (22.47 ± 0.36 vs. 23.25 ± 0.29). This difference in CAG length between patients with low and high T levels (20.38 ± 0.51 vs. 21.98 ± 0.29) was highly significant (P = 0.004) when only the shorter allele of each individual was considered. Ethnic differences were also evident in our data; Indian subjects had a significantly shorter AR-CAG length compared with Chinese, being 22.08 ± 0.50 and 23.16 ± 0.17, respectively. Our data indicate an association between short CAG repeat length and the subset of anovulatory patients with low serum androgens, suggesting that the pathogenic mechanism of polycystic ovaries in these patients could be due to the increased intrinsic androgenic activity associated with short AR alleles.
Serum Dehydroepiandrosterone Sulfate Concentration as an Indicator of Adrenocortical Suppression in Asthmatic Children Treated with Inhaled Steroids
Authors: Kannisto Senja , Korppi Matti , Remes Kyllikki , Voutilainen Raimo
Published: January 2014

ACTH regulates adrenal androgen production, which may thus be reduced during glucocorticosteroid therapy. Dehydroepiandrosterone sulfate is the most abundant androgen secreted by the adrenals. We wished to evaluate whether serum levels of dehydroepiandrosterone sulfate can be used as an indicator of adrenal suppression during inhaled steroid treatment in children. Sixty school-aged children with newly diagnosed asthma were randomly divided into budesonide (n = 30) and fluticasone propionate (n = 30) groups. Fifteen cromone-treated children served as a control group. The budesonide dose was 800 μg/d during the first 2 months and 400 μg/d thereafter. The respective fluticasone propionate doses were 500 and 200μ g/d. Serum dehydroepiandrosterone sulfate concentrations were measured before and after 2 and 4 months of treatment.

In the budesonide group, serum dehydroepiandrosterone sulfate decreased from the baseline by a mean of 21% (95% confidence interval, 13–29%; P < 0.001) after 2 months of high dose treatment and by 16% (95% confidence interval, 8–25%; P < 0.001) after 4 months of treatment. In the fluticasone propionate group, the respective figures were 10% (95% confidence interval, 4–16%; P < 0.01) and 6% (95% confidence interval, 16% decrease–3% increase; P = NS). A low dose ACTH test indicated adrenocortical suppression at 4 months in 14 (23%) steroid-treated children. In these children, dehydroepiandrosterone sulfate decreased by a mean of 21% (95% confidence interval, 14–28%), whereas in those 46 steroid-treated children with normal ACTH test results, dehydroepiandrosterone sulfate decreased by 8% (95% confidence interval, 0–16%; P < 0.05 between these groups). In the control group, dehydroepiandrosterone sulfate levels tended to increase (by a mean of 26%), reflecting the normal physiological change at this age.

In conclusion, inhaled steroid treatment suppresses dehydroepiandrosterone sulfate production in a dose-dependent manner. Monitoring of serum dehydroepiandrosterone sulfate concentrations can be used as a practical method to follow adrenocortical function and to detect its suppression during inhaled steroid treatment in children.
Body Composition, Fasting Leptin, and Sex Steroid Administration Determine GH Sensitivity in Peripubertal Short Children
Authors: Coutant Régis , Boux de Casson Florence , Rouleau Stéphanie , Douay Olivier , Mathieu Elisabeth , Audran Maurice , Limal Jean Marie
Published: January 2014

Serum IGF-I levels in GH-treated subjects demonstrate a wide range of responsiveness to GH. However, the factors influencing GH sensitivity are not well known. The aim of this work was 1) to test whether body composition (determined by dual energy x-ray absorptiometry) or factors related to body composition (fasting blood glucose, FFA, C-peptide, leptin, and insulin sensitivity determined by an insulin tolerance test) influence GH sensitivity; and 2) to study the effect of sex steroid priming on GH sensitivity. We measured serum IGF-I at baseline and 24 h after a single administration of GH (2 mg/m2) in 60 healthy prepubertal and early pubertal children (height, −2.1 ± 1.0 sd score). GH sensitivity, as estimated by the increase in serum IGF-I after GH administration (difference between stimulated and baseline serum IGF-I = δ IGF-I), was also determined after a short-term administration of oral ethinyl E2 in girls and im T in boys.

The serum IGF-I concentration was 297 ± 114 μg/liter at baseline and increased to 429 ± 160 μg/liter, corresponding to a 46 ± 29% increase over the baseline value (P < 0.0001, stimulated vs. baseline serum IGF-I). δ IGF-I was not different between gender or pubertal stage. There were positive correlations (P< 0.001) between δ IGF-I and adiposity (total body fat, r = 0.62; trunk fat, r = 0.62), fasting leptin (r = 0.64), and C-peptide (r = 0.54), and a negative correlation with fasting FFA (r = −0.33; P < 0.05) even after adjustment for age, gender, and pubertal stage. These factors remained significant independent predictors of the absolute as well as the percent increase in serum IGF-I in multiple regression analyses. Priming with T and ethinyl E2 had a similar stimulating effect on the serum GH peak in response to the insulin tolerance test. In boys, serum baseline IGF-I increased by 60%, and δ IGF-I was similar after vs. before T administration. By contrast, in girls, serum baseline IGF-I was similar, and δ IGF-I was 60% less after vs. before ethinyl E2 administration.

This study indicates that 1) GH sensitivity is determined by fat mass, serum fasting leptin, C-peptide, and FFA; and 2) oral ethinyl E2 and im T have divergent effects on the IGF-I response to a single administration of GH.
Human Types 1 and 3 3α-Hydroxysteroid Dehydrogenases: Differential Lability and Tissue Distribution1
Authors: Dufort Isabelle , Labrie Fernand , Luu-The Van
Published: January 2014

3α-Hydroxysteroid dehydrogenases (3α-HSDs) catalyze the conversion of 3-ketosteroids to 3α-hydroxy compounds. The best known 3α-HSD activity is the transformation of the most potent natural androgen, dihydrotestosterone, into 5α-androstan-3α,17β-diol (3α-diol), a compound having much lower activity. Previous reports show that 3α-HSDs are involved in the metabolism of glucocorticoids, progestins, prostaglandins, bile acid precursors, and xenobiotics. 3α-HSDs could, thus, play a crucial role in the control of a series of active steroid levels in target tissues. In the human, type 1 3α-HSD was first identified as human chlordecone reductase. Recently, we have isolated and characterized type 3 3α-HSD that shares 81.7% identity with human type 1 3α-HSD. The transfection of vectors expressing types 1 and 3 3α-HSD in transformed human embryonic kidney (HEK-293) cells indicates that both enzymes efficiently catalyze the transformation of dihydrotestosterone into 3α-diol in intact cells. However, when the cells are broken, the activity of type 3 3α-HSD is rapidly lost, whereas the type 1 3α-HSD activity remains stable. We have previously found that human type 5 17β-HSD which possesses 84% and 86% identity with types 1 and 3 3α-HSD, respectively, is also labile, whereas rodent enzymes such as mouse type 5 17β-HSD and rat 3α-HSD are stable after homogenization of the cells. The variable stability of different enzymatic activities in broken cell preparations renders the comparison of different enzymes difficult. RNA expression analysis indicates that human type 1 3α-HSD is expressed exclusively in the liver, whereas type 3 is more widely expressed and is found in the liver, adrenal, testis, brain, prostate, and HaCaT keratinocytes. Based on enzymatic characteristics and sequence homology, it is suggested that type 1 3α-HSD is an ortholog of rat 3α-HSD while type 3 3α-HSD, which must have diverged recently, seems unique to human and is probably more involved in intracrine activity.
Infiltration of Differentiated Thyroid Carcinoma by Proliferating Lymphocytes Is Associated with Improved Disease-Free Survival for Children and Young Adults1
Authors: Gupta Shalini , Patel Aneeta , Folstad Angela , Fenton Cydney , Dinauer Catherine A. , Tuttle R. Michael , Conran Richard , Francis Gary L.
Published: January 2014

An immune response directed against thyroid cancer might be important in preventing metastasis and recurrence. This idea is supported by previous observations showing that adults with autoimmune thyroiditis or lymphocytic infiltration surrounding papillary thyroid carcinoma (PTC) have improved disease-free survival. The long-term outcome for differentiated thyroid cancer is even more favorable for children and young adults. If the immune response is important, we hypothesized that tumor-associated lymphocytes with a high proliferation index would be found in thyroid cancers from children and young adults and would be associated with improved disease-free survival. Using immunohistochemistry, we examined 39 childhood PTC, 9 follicular thyroid carcinomas, 2 medullary thyroid carcinomas, 11 benign thyroid lesions, and 2 normal thyroid glands for the presence of lymphocytes (leukocyte common antigen) and lymphocyte proliferation (proliferating cell nuclear antigen, Ki-67). The majority of PTC (65%) and follicular thyroid carcinomas (75%) from children and young adults contained lymphocytes in the immediate vicinity of thyroid cancers, but only 7 (18%) patients with PTC also had a diagnosis of autoimmune thyroiditis. Disease-free survival did not correlate with the presence or number of lymphocytes per high power field. In contrast, disease-free survival was significantly improved (P= 0.01) for thyroid cancers with the greatest number of Ki-67-positive lymphocytes per high power field. The number of lymphocytes per high powered field was greater for multifocal PTC (P = 0.023), and the number of proliferating lymphocytes was greatest for PTC with regional lymph node involvement (30.5 ± 12.3 vs. 6.8 ± 5.0; P = 0.047). We conclude that proliferation of tumor-associated lymphocytes is associated with improved disease-free survival for children and young adults with thyroid cancer.
G-308A Polymorphism of the Tumor Necrosis Factorα Gene Promoter and Salivary Cortisol Secretion1
Authors: Rosmond Roland , Chagnon Monique , Bouchard Claude , Björntorp Per
Published: January 2014

The objective of the current study was to examine the potential impact of the G→A substitution at position −308 of the tumor necrosis factor α (TNF-α) gene promoter on obesity and estimates of insulin, glucose, and lipid metabolism as well as circulating hormones including salivary cortisol in 284 unrelated Swedish men born in 1944. The subjects were genotyped by using PCR amplification of the 5′ untranslated region of the TNF-α gene followed by digestion with the restriction enzyme NcoI. The frequencies were 0.77 for allele G and 0.23 for allele A. Tests for differences in salivary cortisol levels between the TNF-α genotypes revealed that there were significantly higher cortisol levels in the morning, before as well as 30 and 60 min after stimulation by a standardized lunch in homozygotes for the rare allele in comparison with the other genotypes. In addition, homozygotes for the rare allele had a tendency toward higher mean values of body mass index, waist to hip ratio, and abdominal sagittal diameter compared with the other genotype groups. The results also indicated a weak trend toward elevated insulin and glucose levels among men with the A/A genotype. In conclusion, a G→A polymorphism in the 5′ untranslated region of the TNF-α gene is associated with elevated morning cortisol levels as well as elevated postprandial cortisol secretion. This increase in cortisol secretion might be the endocrine mechanism underlying the previously observed associations between the NcoI TNF-α polymorphism and obesity as well as insulin resistance. However, to what extent this polymorphism is associated with these conditions is uncertain from the present data.