bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prepro-Orexin and Orexin Receptor mRNAs Are Differentially Expressed in Peripheral Tissues of Male and Female Rats
Authors: Jöhren Olaf , Neidert Steffi J. , Kummer Marco , Dendorfer Andreas , Dominiak Peter 
Published: January 2014

Abstract
Orexins are produced specifically by neurons located in the lateral hypothalamus. Recent results suggested peripheral actions of orexins. Therefore, we analyzed the mRNA expression of prepro-orexin and the orexin receptor subtypes OX1 and OX2 in peripheral rat tissues. Using real-time quantitative RT-PCR we detected significant amounts of prepro-orexin mRNA in testis, but not in ovaries. OX1 receptor mRNA was highly expressed in the brain and at lower levels in the pituitary gland. Only small amounts of OX1 receptor mRNA were found in other tissues such as kidney, adrenal, thyroid, testis, ovaries, and jejunum. Very high levels of OX2 receptor mRNA, 4-fold higher than in brain, were found in adrenal glands of male rats. Low amounts of OX2 receptor mRNA were present in lung and pituitary. In adrenal glands, OX2 receptor mRNA was localized in the zona glomerulosa and reticularis by in situ hybridization, indicating a role in adrenal steroid synthesis and/or release. OX1 receptor mRNA in the pituitary and OX2 receptor mRNA in the adrenal gland were much higher in male than in female rats. In the hypothalamus, OX1 receptor mRNA was slightly elevated in female rats. The differential mRNA expression of orexin receptor subtypes in peripheral organs indicates discrete peripheral effects of orexins and the existence of a peripheral orexin system. This is supported by the detection of orexin A in rat plasma. Moreover, the sexually dimorphic expression of OX1 and OX2 receptors in the hypothalamus, pituitary, and adrenal glands suggests gender-specific roles of orexins in the control of endocrine functions.
Glucose Relays Information Regarding Nutritional Status to the Neural Circuits That Control the Somatotropic, Corticotropic, and Gonadotropic Axes in Adult Male Rhesus Macaques
Authors: Lado-Abeal Joaquin , Veldhuis Johannes D. , Norman Reid L. 
Published: January 2014

Abstract
In male mammals, the neuroendocrine responses to fasting include increased GH and cortisol secretion and suppressed LH and T levels. Because blood glucose levels fall during fasting, we hypothesized that this modest, but consistent, change in blood glucose was a metabolic signal for the neuroendocrine adjustments of reproductive and metabolic hormones. Glucose (d-dextrose, 480 kcal/d) was infused into fasted (48 h) adult male rhesus macaques; and LH, cortisol, and GH were measured in plasma from samples collected at 15-min intervals for the last 15 h of the fast. We analyzed hormone secretion by deconvolution analysis, and the orderliness of release patterns by the approximate entropy statistic. Circulating blood glucose was 76 ± 7 mg/dl in the fed control group, significantly higher (P &lt; 0.01) than the level of 56 ± 3 mg/dl in the fasted group. The increase in GH pulsatility and the 2-fold elevation in cortisol levels observed in the fasted male macaques were prevented by parenteral glucose delivery. The suppression of LH in fasted animals was not relieved by glucose infusions but seemed to be partially prevented in three of the animals. These findings are consistent with the hypothesis that glucose serves as a signal of nutritional status controlling adaptive neuroendocrine responses to fasting in the primate.
Dietary Phosphorus Transcriptionally Regulates 25-Hydroxyvitamin D-1α-Hydroxylase Gene Expression in the Proximal Renal Tubule
Authors: Zhang Martin Y. H. , Wang Xuemei , Wang Jonathan T. , Compagnone Nathalie A. , Mellon Synthia H. , Olson Jean L. , Tenenhouse Harriet S. , Miller Walter L. , Portale Anthony A. 
Published: January 2014

AbstractSynthesis of the hormone 1,25-dihydroxyvitamin D, the biologically active form of vitamin D, occurs in the kidney and is catalyzed by the mitochondrial cytochrome P450 enzyme, 25-hydroxyvitamin D-1α-hydroxylase (1α-hydroxylase). We sought to characterize the effects of changes in dietary phosphorus on the kinetics of renal mitochondrial 1α-hydroxylase activity and the renal expression of P450c1α and P450c24 mRNA, to localize the nephron segments involved in such regulation, and to determine whether transcriptional mechanisms are involved. In intact mice, restriction of dietary phosphorus induced rapid, sustained, approximately 6- to 8-fold increases in renal mitochondrial 1α-hydroxylase activity and renal P450c1α mRNA abundance. Immunohistochemical analysis of renal sections from mice fed the control diet revealed the expression of 1α-hydroxylase protein in the proximal convoluted and straight tubules, epithelial cells of Bowman’s capsule, thick ascending limb of Henle’s loop, distal tubule, and collecting duct. In mice fed a phosphorusrestricted diet, immunoreactivity was significantly increased in the proximal convoluted and proximal straight tubules and epithelial cells of Bowman’s capsule, but not in the distal nephron. Dietary phosphorus restriction induced a 2-fold increase in P450c1α gene transcription, as shown by nuclear run-on assays. Thus, the increase in renal synthesis of 1,25-dihydroxyvitamin D induced in normal mice by restricting dietary phosphorus can be attributed to an increase in the renal abundance of P450c1α mRNA and protein. The increase in P450c1α gene expression, which occurs exclusively in the proximal renal tubule, is due at least in part to increased transcription of the P450c1α gene.
Identification of a Potential Receptor for Both Peptide Histidine Isoleucine and Peptide Histidine Valine
Authors: Tse Dicky Lai-Yin , Pang Ronald Ting-Kai , Wong Anderson On-Lam , Chan Siu-Ming , Vaudry Hubert , Chow Billy Kwok-Chong 
Published: January 2014

AbstractPeptide histidine isoleucine (PHI), peptide histidine valine (PHV), and vasoactive intestinal polypeptide (VIP) are cosynthesized from the same precursor and share high levels of structural similarities with overlapping biological functions. In this study, the first PHI/PHV receptor was isolated and characterized in goldfish. To study this receptor using homologous peptides, we have also characterized the goldfish prepro-PHI/VIP, and, surprisingly, a shorter transcript lacking the VIP coding region was isolated. A PHI/VIP precursor without the VIP coding sequence has never before been reported. Initial functional expression of the PHI/PHV receptor in Chinese hamster ovary cells revealed that it could be activated by human PHV [50% effective concentration (EC50): 43 nm] and to a lesser extent human PHI (EC50: 133 nm) and helodermin (EC50: 166 nm) but not fish and mammalian pituitary adenylate cyclase-activating polypeptides and VIPs. Subsequent studies indicated that, similar to the pituitary adenylate cyclase-activating polypeptide receptors (PAC1-R, VPAC1-R, and VPAC2-R), the receptor isolated in this study is able to interact with goldfish PHI and its C-terminally extended form, PHV with EC50 values 93 and 43 nm, respectively. Northern blot and RT-PCR/Southern blot analyses revealed that the PHI/VIP gene is expressed in the intestine, brain, and gall bladder and the PHI/PHV receptor gene is primarily expressed in the pituitary and to a lesser extend in the intestine and gall bladder, suggesting that PHI/PHV may play a role, notably in the regulation of pituitary function. In conclusion, our results demonstrate for the first time the existence of a PHI/PHV receptor, indicating that the functions of PHI and PHV could be mediated by their own receptor in addition to VIP receptors.
Evidence that Brain-Derived Neurotrophic Factor Acts as an Autocrine Factor on Pituitary Melanotrope Cells of Xenopus laevis
Authors: Kramer Bianca M. R. , Cruijsen Peter M. J. M. , Ouwens Debbie T. W. M. , Coolen Marcel W. , Martens Gerard J. M. , Roubos Eric W. , Jenks Bruce G. 
Published: January 2014

AbstractWe have investigated the physiological regulation and functional significance of brain-derived neurotrophic factor (BDNF) in the endocrine melanotrope cells of the pituitary pars intermedia of the amphibian Xenopus laevis, which can adapt its skin color to the light intensity of its environment. In black-adapted animals, melanotrope cells produce and release α-melanophore-stimulating hormone (α-MSH). In white-adapted animals, the activity of melanotrope cells is inhibited by neuronal input. Using Western blotting and immunocytochemistry at the light and electron microscopical level, we have detected both the BDNF precursor and the mature BDNF protein in Xenopus melanotrope cells. In situ hybridization and RT-PCR revealed the presence of BDNF mRNA in the pituitary pars intermedia, indicating that BDNF is synthesized in the melanotropes. Real-time quantitative RT-PCR showed that levels of BDNF mRNA in melanotrope cells are about 25 times higher in black- than in white-adapted animals. Although there is no difference in the amount of stored mature BDNF, the amount of BDNF precursor protein is 3.5 times higher in melanotropes of black-adapted animals than in those of white-adapted animals. These data indicate that BDNF mRNA expression and BDNF biosynthesis are up-regulated in active melanotrope cells. Because immunoelectron microscopy showed that BDNF is located in melanotrope secretory granules, BDNF is probably coreleased with α-MSH via the regulated secretory pathway. Superfusion and 3H-amino acid incorporation studies demonstrated that BDNF stimulates the release of α-MSH and the biosynthesis of its precursor protein, POMC. Our results provide evidence that BDNF regulates the activity of Xenopus melanotrope cells in an autocrine fashion.
Cellular and Molecular Events Associated with the Bone-Protecting Activity of the Noncalcemic Vitamin D Analog Ro-26-9228 in Osteopenic Rats
Authors: Peleg Sara , Uskokovic Milan , Ahene Ago , Vickery Brian , Avnur Zafrira 
Published: January 2014

Abstract
We have examined several analogs of 1α,25-dihydroxyvitamin D3 [1,25-(OH)2D3] in an animal model of osteoporosis (ovariectomized rats) to identify a compound with a greater therapeutic range than 1,25-(OH)2D3 for treatment of this bone disease. Here, we report that one analog, Ro-26-9228, had a bone-protecting effect but did not induce hypercalcemia at a wide concentration range. Analysis of biochemical markers and the bone histomorphometry of analog-treated rats suggested that Ro-26-9228 acted by inhibiting bone resorption and increasing the number of differentiated osteoblasts. To determine the basis for the segregation between hypercalcemia and bone-protecting action, we examined gene expression in tissues that regulate calcium homeostasis. We found that 1,25-(OH)2D3 induced 24-hydroxylase mRNA expression in the duodena of ovariectomized rats, but Ro-26-9228 did not. Furthermore, in the duodena of intact animals, 1,25-(OH)2D3 induced a significant increase in calbindin D 9K and plasma membrane calcium pump 1 mRNAs, but Ro-26-9228 had no effect on these mRNAs. On the other hand, the osteoblast-specific gene products osteocalcin and osteopontin were significantly up-regulated in trabecular bone by both the natural hormone and Ro-26-9228. Further investigation of gene-regulatory events in trabecular bone revealed that both 1,25-(OH)2D3 and Ro-26-9228 up-regulated TGF β1 and β2 mRNAs. We concluded that the unique properties of Ro-26-9228 include preferential gene regulation in osteoblasts over duodenum and effective induction of growth factors in bone.
Stress Activation of Cortex and Hippocampus Is Modulated by Sex and Stage of Estrus
Authors: Figueiredo Helmer F. , Dolgas Charles M. , Herman James P. 
Published: January 2014

Abstract
Sex plays a major role in stress integration and stress-related affective disease states. Notably, neurocircuits regulating organismic responses to stress are prime targets for central gonadal steroid action. To assess the roles of sex and estrous cycle in central stress integration, we analyzed c-fos mRNA expression in hypothalamic-pituitary-adrenocortical-related regions of stressed male and cycling female (proestrous, estrous, and diestrous) rats. At 60 min after the onset of acute restraint stress, all animal groups showed induction of c-fos mRNA in the frontal cortex, cingulate cortex, piriform cortex, hippocampus, hypothalamic paraventricular nucleus (PVN), medial amygdala, and lateral septum. However, the magnitude of c-fos induction in cortical and hippocampal regions was substantially lower in proestrous and estrous females compared with males and diestrous females. Sex- and estrus cycle-related changes are region specific, as no difference in c-fos induction occurred in the hypothalamic PVN, medial amygdala, or ventrolateral septum in any group. Furthermore, induction of c-fos mRNA in limbic cortexes (but not hippocampus) was positively correlated with progesterone and negatively correlated with ACTH levels. Taken together, this study indicates that cortical structures are differentially stress activated in females depending on the phase of the estrous cycle, perhaps in a progesterone-dependent fashion.
Identification and Characterization of Novel Estrogen Receptor-β-Sparing Antiprogestins
Authors: Sathya Ganesan , Jansen Michelle S. , Nagel Susan C. , Cook C. Edgar , McDonnell Donald P. 
Published: January 2014

AbstractThe steroid hormones estrogen and progesterone together regulate the development and maintenance of the female reproductive system. The actions of these two hormones are mediated by their respective nuclear receptors located within overlapping cell populations in target organs. The molecular mechanism of action of these two hormones has been defined to a large extent using estrogen receptor (ER) and progesterone receptor (PR) antagonists. In the case of ER, the available antagonists are highly receptor selective. With respect to PR, however, the available antiprogestins also interact with the receptors for glucocorticoids, mineralocorticoids, and androgens. Whereas these cross-reactivities can usually be managed in studies of female reproductive function, it is the recent demonstration that RU486 is an effective antagonist of the β-isoform of ER that suggested the need for more selective antiprogestins. In this study, we used cell-based transcriptional assays combined with screens using coactivator peptide analogs to identify two novel classes of antiprogestins that distinguish themselves from the antiprogestin RU486 in the manner they interact with PR. One class exhibits the characteristics of a pure antiprogestin in that its members bind to the receptor and induce a conformational change that prevents the presentation of two potential coactivator binding surfaces on the protein. The second class of compounds distinguish themselves from RU486 in that they are ERβ sparing. When tested in vivo the ER-sparing antiprogestins were as effective as RU486 in suppressing superovulation. It is anticipated that the availability of these new antiprogestins will advance the studies of PR pharmacology in a manner similar to how the availability of selective ER modulators has helped the study of ER action.
Polymorphism in Vitamin D-Binding Protein as a Genetic Risk Factor in the Pathogenesis of Endometriosis
Authors: Faserl Klaus , Golderer Georg , Kremser Leopold , Lindner Herbert , Sarg Bettina , Wildt Ludwig , Seeber Beata 
Published: January 2014

Context: Previous studies have implicated a deficiency in the inflammatory response in women who develop endometriosis. The specific immunological deficits have not been completely elucidated.
Objective: Our objective was to identify differences in protein expression in serum that might shed light on the pathophysiology of endometriosis.
Design and Setting: This cross-sectional study of women undergoing laparoscopy between 2003 and 2005 took place at a university medical center.
Patients: Patients included consenting women age 18-49 yr undergoing surgery for pain and/or infertility or elective tubal ligation. Women with acute or chronic medical conditions were excluded.
Intervention: Blood was collected preoperatively.
Main Outcome Measure: Proteomic analysis of serum was done using two-dimensional difference gel electrophoresis.
Results: We found 25 protein spots with a significant difference in abundance between women with endometriosis and controls, including acute-phase proteins and complement components. The abundance of vitamin D-binding protein was higher in all endometriosis pools by a factor of approximately 3 compared with the control pool (P &lt; 0.02). Analysis of specific allele products using nano-LC-ESI-MS indicated that it was the GC*2 allele product that was in greater concentration in serum pools, as well as in single validation samples, in women with endometriosis (P = 0.006). In contrast to the GC*1 allele product, which is readily converted to a potent macrophage factor (Gc protein-derived macrophage-activating factor), the GC*2 allele product undergoes practically no such conversion.
Conclusions: We speculate that the inability to sufficiently activate macrophages’ phagocytotic function in those carrying the GC*2 polymorphism (more prevalent in endometriosis) may allow endometriotic tissues to implant in the peritoneal cavity. Future studies evaluating specific vitamin D-binding protein polymorphisms as a risk factor for endometriosis in larger populations of women are warranted.
Clinical, Biochemical, and Molecular Characterization of Macronodular Adrenocortical Hyperplasia of the Zona Reticularis: A New Syndrome
Authors: Ghayee Hans K. , Rege Juilee , Watumull Lori M. , Nwariaku Fiemu E. , Carrick Kelley S. , Rainey William E. , Miller Walter L. , Auchus Richard J. 
Published: January 2014

Context: Macronodular adrenocortical hyperplasia classically presents with progressive hypercortisolemia and Cushing syndrome. We describe a 29-year-old man with massive macronodular adrenocortical hyperplasia without hypercortisolemia but rather markedly elevated and nonsuppressible production of dehydroepiandrosterone (DHEA) and its sulfate (DHEAS).
Objective: To characterize the clinical and molecular features of this case and to determine whether the tissue biochemically resembles the zona reticularis or fetal adrenal.
Setting: University clinic, hospital, and laboratories.
Design: Static and dynamic blood and urine testing were performed preoperatively. Tissue was studied by light microscopy, immunoblot, RNA microarray, and enzyme assay.
Participant: A 29-year-old man with incidentally discovered bilateral adrenal enlargement.
Intervention: Bilateral adrenalectomy.
Main Outcome Measures: Molecular studies compared with control samples.
Results: Hypercortisolism and 21-hydroxylase deficiency were excluded. DHEA, DHEAS, and 17-hydroxypregnenolone were markedly elevated and did not suppress with dexamethasone 2 mg/d for 4 days. Homogenates of the adrenals demonstrated high 17-hydroxylase, good 17,20-lyase, and low or absent 21-hydroxylase and 3β-hydroxysteroid dehydrogenase activities. Immunoblots confirmed robust expression of cytochrome P450c17 and AKR1C3 but not P450c21. Microarray analysis demonstrated high CYP11A1 and CYP17A1 expression but low or absent HSD3B1, HSD3B2, and CYP21A2 expression. Expression of mRNA for cytochrome b5 (CYB5A) and AKR1C3, markers of the zona reticularis, were markedly elevated.
Conclusion: This is the first case of macronodular hyperplasia of the adrenal zona reticularis confirmed with studies of enzyme activity, mRNA expression, and protein identification. We speculate that this condition can be clinically silent in men but might cause severe hyperandrogenemia in women.
Sustained Endoplasmic Reticulum Stress as a Cofactor of Oxidative Stress in Decidual Cells from Patients with Early Pregnancy Loss
Authors: Liu Ai-Xia , He Wei-Hua , Yin Li-Jun , Lv Ping-Ping , Zhang Yu , Sheng Jian-Zhong , Leung Peter C. K. , Huang He-Feng 
Published: January 2014

Background: Oxidative stress (OS) is a common pathological background for different etiologies of early pregnancy loss (EPL). It has been suggested that elevated reactive oxygen species trigger endoplasmic reticulum (ER) stress by influencing ER function. However, it is unclear whether ER stress is associated with EPL.
Objectives: The aim of the study was to determine whether and how ER stress occurs during the development of EPL.
Approaches: Proteomic analysis was performed on decidua from women with EPL, and then ER stress markers, redox status, apoptotic features, and cell viability were analyzed in EPL decidual cells (DCs).
Results: EPL decidua were characterized by decreased levels of glucose-regulated protein 78 (GPR78) and valosin-containing protein and burdened with ubiquitinated proteins. Evidence of ER stress-induced apoptosis in EPL DCs was demonstrated by extensive dilation of ER, morphological features of apoptosis, and activation of caspase-4 and caspase-12. Furthermore, H2O2 reduced the viabilities in both EPL and control DCs, whereas EPL DCs were more vulnerable to additional OS challenge than the controls as a result of failed induction of GRP78 expression. The cell survival percentages of DCs were dose-dependently reduced by H2O2 and could be reversed in the presence of vitamin E. This effect was partly mediated by reducing the amount of misfolded proteins rather than regulating GRP78 expression.
Conclusions: The sum of these observations demonstrate for the first time that sustained ER stress occurs in EPL DCs and the potentially vicious relationship between ER stress and OS is likely to play an important role in the development of EPL.
Robust Leptin Secretory Responses to Dexamethasone in Obese Subjects*
Authors: Dagogo-Jack Samuel , Selke Gregg , Melson Angela K. , Newcomer John W. 
Published: January 2014

Abstract
Although leptin reverses obesity in rodents, its function and regulation in humans are unknown. Glucocorticoids have been reported to stimulate leptin production in both rodents and humans, but data assessing the effect of obesity on dynamic leptin secretory responses are unavailable. We, therefore, studied 52 lean and obese subjects [20 men and 32 women; aged 19–84 yr; body mass index (BMI) range, 16–47 kg/m2] randomized to treatment with dexamethasone (total dose, 10 mg/4 days) or placebo. Compared with placebo, dexamethasone increased (P = 0.0001) plasma leptin levels by 64–111% above baseline values within 2–4 days. The increases occurred in all ages, showed no sexual dimorphism, and were particularly robust in obese subjects. After dexamethasone treatment, significant interactions were observed between the change in plasma leptin and BMI (P = 0.0001), baseline plasma leptin (P = 0.0006) and plasma dexamethasone levels (P = 0.04), but not age (P = 0.28); an apparent interaction with plasma insulin no longer was significant after controlling for BMI. These results confirm dexamethasone-induced hyperleptinemia in humans and further demonstrate that the response is not defective in obesity.