Hypocretin/orexin increases the expression of steroidogenic enzymes in human adrenocortical NCI H295R cells

2009 ◽  
Vol 297 (5) ◽  
pp. R1601-R1609 ◽  
Author(s):  
Jan Wenzel ◽  
Nicole Grabinski ◽  
Cordula A. Knopp ◽  
Andreas Dendorfer ◽  
Manjunath Ramanjaneya ◽  
...  

Hypocretins/orexins act through two receptor subtypes: OX1 and OX2. Outside the brain, orexin receptors are expressed in adrenal glands, where orexins stimulate the release of glucocorticoids. To further address the regulation of steroidogenesis, we analyzed the effect of orexins on the expression of steroidogenic enzymes in human adrenocortical National Cancer Institute (NCI) H295R cells by qPCR. In NCI H295R cells, OX2 receptors were highly expressed, as they were in human adrenal glands. After treatment of NCI H295R cells with orexin A for 12–24 h, the cortisol synthesis rate was significantly increased, whereas 30 min of treatment showed no effect. While CYP11B1 and CYP11B2 mRNA levels were increased already at earlier time points, the expression of HSD3B2 and CYP21 mRNA was significantly up-regulated after treatment with orexin A for 12 h. Likewise, orexin B increased CYP21 and HSD3B2 mRNA levels showing, however, a lower potency compared with orexin A. The mRNA levels of CYP11A and CYP17 were unaffected by orexin A. OX2 receptor mRNA levels were down-regulated after 12 and 24 h of orexin A treatment. Orexin A increased intracellular Ca2+ but not cAMP concentrations in NCI H295R cells. Furthermore, inhibition of PKC and MAPK kinase/ERK kinase (MEK1/2) prevented the increase of HSD3B2 expression by orexin A. Accordingly, orexin A treatment of NCI H295R cells markedly enhanced ERK1/2 phosphorylation that was prevented by PKC and, in part, PKA inhibition. In conclusion, orexins may influence adrenal steroidogenesis by differential regulation of the expression of steroidogenic enzymes involving Ca2+, as well as PKC-ERK1/2 signaling.

2011 ◽  
Vol 209 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Karine Bibeau ◽  
Mélissa Otis ◽  
Jean St-Louis ◽  
Nicole Gallo-Payet ◽  
Michèle Brochu

In low sodium-induced intrauterine growth restricted (IUGR) rat, foetal adrenal steroidogenesis as well as the adult renin–angiotensin–aldosterone system (RAAS) is altered. The aim of the present study was to determine the expression of cytochrome P450 aldosterone synthase (P450aldo) and of angiotensin II receptor subtypes 1 (AT1R) and 2 (AT2R) in adult adrenal glands and whether this expression could be influenced by IUGR and by high-salt intake in a sex-specific manner. After 6 weeks of 0.9% NaCl supplementation, plasma renin activity, P450aldo expression and serum aldosterone levels were decreased in all groups. In males, IUGR induced an increase in AT1R, AT2R, and P450aldo levels, without changes in morphological appearance of the zona glomerulosa (ZG). By contrast, in females, IUGR had no effect on the expression of AT1R, but increased AT2R mRNA while decreasing protein expression of AT2R and P450aldo. In males, salt intake in IUGR rats reduced both AT1R mRNA and protein, while for AT2R, mRNA levels decreased whereas protein expression increased. In females, salt intake reduced ZG size in IUGR but had no affect on AT1R or AT2R expression in either group. These results indicate that, in response to IUGR and subsequently to salt intake, P450aldo, AT1R, and AT2R levels are differentially expressed in males and females. However, despite these adrenal changes, adult IUGR rats display adequate physiological and adrenal responses to high-salt intake, via RAAS inhibition, thus suggesting that extra-adrenal factors likely compensate for ZG alterations induced by IUGR.


2005 ◽  
Vol 90 (6) ◽  
pp. 3544-3549 ◽  
Author(s):  
R. Spinazzi ◽  
M. Rucinski ◽  
G. Neri ◽  
L. K. Malendowicz ◽  
G. G. Nussdorfer

Orexins A and B are hypothalamic peptides that originate from the proteolytic cleavage of preproorexin and act through two subtypes of receptors, named OX1-R and OX2-R. OX1-R almost exclusively binds orexin-A, whereas OX2-R is nonselective for both orexins. We previously found that orexin-A, via the OX1-R, stimulates cortisol secretion from dispersed human adrenocortical cells. In this study, we demonstrate that six of eight cortisol-secreting adenomas expressed preproorexin mRNA, and seven of 10 adenomas contained measurable amounts of orexin-A but not orexin-B. Normal adrenal cortexes neither expressed preproorexin nor contained orexins. All adenomas expressed OX1-R and OX2-R mRNAs, and real-time PCR showed that the expression of both receptors was up-regulated in adenomas, compared with normal adrenal cortex. Orexin-A concentration-dependently raised basal cortisol secretion from freshly dispersed normal and adenomatous cells, minimal and maximal effective concentrations being 10−10 and 10−8m, and the peptide efficacy (percent increase elicited by 10−8m orexin-A) was significantly higher in adenomas than in the normal adrenal cortex. Orexin-B was ineffective, thereby indicating that orexin secretagogue action is mediated by the OX1-R. In contrast, both orexins (10−8m) raised the proliferative activity of cultured normal and adenomatous cells, suggesting that this effect is mediated by OX2-R or both receptor subtypes. Collectively, our findings allow us to conclude that the orexin system is overexpressed in cortisol-secreting adenomas and suggest that orexin-A may act as an autocrine-paracrine regulator of the secretory activity and growth of some of these adrenal tumors.


2012 ◽  
Vol 215 (3) ◽  
pp. 403-412 ◽  
Author(s):  
R van der Pas ◽  
L J Hofland ◽  
J Hofland ◽  
A E Taylor ◽  
W Arlt ◽  
...  

The antifungal agent ketoconazole is often used to suppress cortisol production in patients with Cushing's syndrome (CS). However, ketoconazole has serious side effects and is hepatotoxic. Here, the in vitro effects of ketoconazole and fluconazole, which might be less toxic, on human adrenocortical steroidogenesis were compared. The effects on steroidogenesis were examined in primary cultures of nine human adrenocortical tissues and two human adrenocortical carcinoma cell lines. Moreover, the effects on mRNA expression levels of steroidogenic enzymes and cell growth were assessed. Ketoconazole significantly inhibited 11-deoxycortisol (H295R cells; maximum inhibition 99%; EC50 0.73 μM) and cortisol production (HAC15 cells; 81%; EC50 0.26 μM and primary cultures (mean EC50 0.75 μM)). In cultures of normal adrenal cells, ketoconazole increased pregnenolone, progesterone, and deoxycorticosterone levels, while concentrations of 17-hydroxypregnenolone, 17-hydroxyprogesterone, 11-deoxycortisol, DHEA, and androstenedione decreased. Fluconazole also inhibited 11-deoxycortisol production in H295R cells (47%; only at 1 mM) and cortisol production in HAC15 cells (maximum inhibition 55%; EC50 35 μM) and primary cultures (mean EC50 67.7 μM). In the cultures of normal adrenals, fluconazole suppressed corticosterone, 17-hydroxypregnenolone, and androstenedione levels, whereas concentrations of progesterone, deoxycorticosterone, and 11-deoxycortisol increased. Fluconazole (1 mM) slightly increased STAR mRNA expression in both cell lines. Neither compound affected mRNA levels of other steroidogenic enzymes or cell number. In conclusion, by inhibiting 11β-hydroxylase and 17-hydroxylase activity, pharmacological concentrations of fluconazole dose dependently inhibit cortisol production in human adrenocortical cells in vitro. Although fluconazole seems less potent than ketoconazole, it might become an alternative for ketoconazole to control hypercortisolism in CS. Furthermore, patients receiving fluconazole because of mycosis might be at risk for developing adrenocortical insufficiency.


2013 ◽  
Vol 305 (9) ◽  
pp. E1049-E1058 ◽  
Author(s):  
Manjunath Ramanjaneya ◽  
Emmanouil Karteris ◽  
Jing Chen ◽  
Marcin Rucinski ◽  
Agnieszka Ziolkowska ◽  
...  

Hormonal regulation of adrenal function occurs primarily through activation of GPCRs. GPCRs are central to many of the body's endocrine and neurotransmitter pathways. Recently, it was shown that activation of GPR103 by its ligand QRFP induced feeding, locomotor activity, and metabolic rate, and QRFP is bioactive in adipose tissue of obese individuals. Given that the adrenal gland is a pivotal organ for energy balance and homeostasis, we hypothesized that GPR103 and QRFP are involved in steroidogenic responses. Using qRT-PCR and immunohistochemistry, we mapped both GPR103 and QRFP in human fetal and adult adrenal gland as well as rat adrenals. Both were primarily localized in the adrenal cortex but not in the medulla. Activation of GPR103 in human adrenocortical H295R cells led to a decrease in forskolin-increased cAMP and an increase of intracellular Ca2+ levels. In addition, treatment of H295R cells with QRFP induced aldosterone and cortisol secretion as measured by ELISA. These increases were accompanied by increased expression and activity of StAR, CYB11B1, and CYP11B2 as assessed by qRT-PCR and luciferase reporter assay, respectively. Using specific inhibitors, we also demonstrated that aldosterone induction involves MAPK, PKC, and/or T-type Ca2+ channel-dependent pathways. These novel data demonstrate that QRFP induces adrenal steroidogenesis in vitro by regulating key steroidogenic enzymes involving MAPK/PKC and Ca2+ signaling pathways.


SLEEP ◽  
2020 ◽  
Vol 43 (Supplement_1) ◽  
pp. A2-A2
Author(s):  
D Kambe ◽  
H Hikichi ◽  
Y Tokumaru ◽  
M Ohmichi ◽  
Y Konno ◽  
...  

Abstract Introduction The orexin system plays a pivotal role in regulating sleep and wakefulness, thus, orexin receptors (OX1 and OX2 receptors) have gained much attention as promising therapeutic targets for the treatment of insomnia. We synthesized a novel and potent dual orexin receptor antagonist (DORA), ORN0829 (investigation code name as TS-142), which was designed to have short-acting effects. Here we report pharmacological and pharmacokinetic profiles of ORN0829 in rats. Methods The antagonistic activities of ORN0829 were assessed using calcium mobilization assays. Ala-orexin A-induced [Ca2+]i response was measured with CHO-K1 cells stably expressing human/rat orexin receptor. Rats implanted the EEG/EMG electrodes were orally administrated ORN0829 at doses of 1, 3 or 10 mg/kg at the dark onset and sleep-wake stages were inspected visually. In addition, pharmacokinetic profiles of ORN0829 were investigated in rats. Results ORN0829 inhibited Ala-orexin A-increased [Ca2+]i response with a Kb of 0.67/0.44 nmol/L (for human/rat OX1 receptor), and with a Kb of 0.84/0.80 nmol/L (for human/rat OX2 receptor), respectively, indicating that ORN0829 is a potent DORA with no species differences. ORN0829 dose-dependently increased total sleep time and reduced sleep onset latency at doses of 1, 3 and 10 mg/kg. Importantly, the ORN0829 levels in plasma and cerebrospinal fluid rapidly reached a maximum concentration, and decreased with an elimination half-life of less than 1 h. Conclusion The present study indicates that ORN0829 is a novel and potent DORA with sleep-promoting effects, and that it exhibits ideal pharmacokinetic profiles (rapid absorption and short half-life) in rats. A phase 2a study of TS-142 using patients with insomnia has been completed, which is presented in a separate poster. Support Taisho Pharmaceutical. Co., Ltd.


2019 ◽  
Vol 22 (11) ◽  
pp. 710-723 ◽  
Author(s):  
Atul P Daiwile ◽  
Subramaniam Jayanthi ◽  
Bruce Ladenheim ◽  
Michael T McCoy ◽  
Christie Brannock ◽  
...  

Abstract Background Methamphetamine (METH) use disorder is prevalent worldwide. There are reports of sex differences in quantities of drug used and relapses to drug use among individuals with METH use disorder. However, the molecular neurobiology of these potential sex differences remains unknown. Methods We trained rats to self-administer METH (0. 1 mg/kg/infusion, i.v.) on an fixed-ratio-1 schedule for 20 days using two 3-hour daily METH sessions separated by 30-minute breaks. At the end of self-administration training, rats underwent tests of cue-induced METH seeking on withdrawal days 3 and 30. Twenty-four hours later, nucleus accumbens was dissected and then used to measure neuropeptide mRNA levels. Results Behavioral results show that male rats increased the number of METH infusions earlier during self-administration training and took more METH than females. Both male and female rats could be further divided into 2 phenotypes labeled high and low takers based on the degree of escalation that they exhibited during the course of the METH self-administration experiment. Both males and females exhibited incubation of METH seeking after 30 days of forced withdrawal. Females had higher basal mRNA levels of dynorphin and hypocretin/orexin receptors than males, whereas males expressed higher vasopressin mRNA levels than females under saline and METH conditions. Unexpectedly, only males showed increased expression of nucleus accumbens dynorphin after METH self-administration. Moreover, there were significant correlations between nucleus accumbens Hcrtr1, Hcrtr2, Crhr2, and Avpr1b mRNA levels and cue-induced METH seeking only in female rats. Conclusion Our results identify some behavioral and molecular differences between male and female rats that had self-administered METH. Sexual dimorphism in responses to METH exposure should be considered when developing potential therapeutic agents against METH use disorder.


2015 ◽  
Vol 45 (4) ◽  
pp. 704-710 ◽  
Author(s):  
Melânia Lazzari Rigo ◽  
Andressa Minussi Pereira Dau ◽  
Werner Giehl Glanzner ◽  
Manoel Martins ◽  
Renato Zanella ◽  
...  

The main objective of this study was to detect the steroidogenic effects of Ang II in bovine theca cells in vitro. Bovine theca cells were obtained from follicles (larger than 10mm of diameter) collected from a local abattoir and submitted to different treatments in a sequence of experiments. In experiment 1, CYP17A1 mRNA profile was evaluated in LH- (10ng ml-1) and Ang II-treated (0.1µM) theca cells. In experiment 2, a dose-response effect of Ang II (0.001; 0.1 e 10µM) plus insulin (100ng ml-1) and LH (100ng ml-1) was evaluated on steroidogenesis of bovine theca cells. Experiment 3 explored the effects of saralasin (an antagonist of Ang II receptors) on steroid production and steroidogenic enzymes regulation in theca cells. After 24 hours, culture media from experiments 2 and 3 was collected to evaluate testosterone and androstenedione levels by High-Performance Liquid Chromatography. In parallel, mRNA levels of key steroidogenic enzymes (HSD3B2, CYP11A1, CYP17A1) and STAR were assessed by RT-PCR. There was no difference in testosterone and androstenedione production between treated and controls groups, as well as in mRNA levels of the evaluated genes. In conclusion, the results suggest that Ang II does not regulate steroidogenesis in bovine theca cells


2000 ◽  
Vol 279 (2) ◽  
pp. E244-E251 ◽  
Author(s):  
Benoît Ruot ◽  
Denis Breuillé ◽  
Fabienne Rambourdin ◽  
Gerard Bayle ◽  
Pierre Capitan ◽  
...  

Plasma albumin is well known to decrease in response to inflammation. The rate of albumin synthesis from both liver and plasma was measured in vivo by use of a large dose ofl-[2H3-14C]valine in rats injected intravenously with live Escherichia coli and in pair-fed control rats during the acute-phase period (2 days postinfection). The plasma albumin concentration was reduced by 50% in infected rats compared with pair-fed animals. Infection induced a fall in both liver albumin mRNA levels and albumin synthesis relative to total liver protein synthesis. However, absolute liver albumin synthesis rate (ASR) was not affected by infection. In plasma, albumin fractional synthesis rate was increased by 50% in infected animals compared with pair-fed animals. The albumin ASR estimated in the plasma was similar in the two groups. These results suggest that hypoalbuminemia is not due to reduced albumin synthesis during sepsis. Moreover, liver and plasma albumin ASR were similar. Therefore, albumin synthesis measured in the plasma is a good indicator of liver albumin synthesis.


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