Showing papers on "Pregnenolone published in 2017"
TL;DR: Results indicate that pregnenolone sulfate together with progesterone are the main steroids that activate CatSper and pristimerin and lupeol can act as contraceptive compounds by averting sperm hyperactivation, thus preventing fertilization.
Abstract: The calcium channel of sperm (CatSper) is essential for sperm hyperactivated motility and fertility The steroid hormone progesterone activates CatSper of human sperm via binding to the serine hydrolase ABHD2 However, steroid specificity of ABHD2 has not been evaluated Here, we explored whether steroid hormones to which human spermatozoa are exposed in the male and female genital tract influence CatSper activation via modulation of ABHD2 The results show that testosterone, estrogen, and hydrocortisone did not alter basal CatSper currents, whereas the neurosteroid pregnenolone sulfate exerted similar effects as progesterone, likely binding to the same site However, physiological concentrations of testosterone and hydrocortisone inhibited CatSper activation by progesterone Additionally, testosterone antagonized the effect of pregnenolone sulfate We have also explored whether steroid-like molecules, such as the plant triterpenoids pristimerin and lupeol, affect sperm fertility Interestingly, both compounds competed with progesterone and pregnenolone sulfate and significantly reduced CatSper activation by either steroid Furthermore, pristimerin and lupeol considerably diminished hyperactivation of capacitated spermatozoa These results indicate that (i) pregnenolone sulfate together with progesterone are the main steroids that activate CatSper and (ii) pristimerin and lupeol can act as contraceptive compounds by averting sperm hyperactivation, thus preventing fertilization
89 citations
TL;DR: Serum steroid paneling by LC-MS/MS is useful for diagnosing ACC by combining the measurement of steroid hormones and their precursors in a single analysis.
Abstract: BACKGROUND: Adrenocortical carcinoma (ACC) is a rare malignancy, with an annual incidence of 1 or 2 cases per million. Biochemical diagnosis is challenging because up to two-thirds of the carcinomas are biochemically silent, resulting from de facto enzyme deficiencies in steroid hormone biosynthesis. Urine steroid profiling by GC-MS is an effective diagnostic test for ACC because of its capacity to detect and quantify the increased metabolites of steroid pathway synthetic intermediates. Corresponding serum assays for most steroid pathway intermediates are usually unavailable because of low demand or lack of immunoassay specificity. Serum steroid analysis by LC-MS/MS is increasingly replacing immunoassay, in particular for steroids most subject to cross-reaction. METHODS: We developed an LC-MS/MS method for the measurement of serum androstenedione, corticosterone, cortisol, cortisone, 11-deoxycorticosterone, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone sulfate, pregnenolone, 17-hydroxypregnenolone, progesterone, 17-hydroxyprogesterone, and testosterone. Assay value in discriminating ACC from other adrenal lesions (phaeochromocytoma/paraganglioma, cortisol-producing adenoma, and lesions demonstrating no hormonal excess) was then investigated. RESULTS: In ACC cases, between 4 and 7 steroids were increased (median = 6), and in the non-ACC groups, up to 2 steroids were increased. 11-Deoxycortisol was markedly increased in all cases of ACC. All steroids except testosterone in males and corticosterone and cortisone in both sexes were of use in discriminating ACC from non-ACC adrenal lesions. CONCLUSIONS: Serum steroid paneling by LC-MS/MS is useful for diagnosing ACC by combining the measurement of steroid hormones and their precursors in a single analysis.
72 citations
TL;DR: Overall, when all time points and FSH doses were analyzed collectively, FSH significantly up-regulated the mRNA expression of its own receptor and the protein level of 3β-HSD from the samples stimulated with FSH.
Abstract: STUDY QUESTION Can granulosa cells produce progesterone (P) in response to FSH stimulation? SUMMARY ANSWER FSH actively promotes P synthesis and output from granulosa cells without luteinization by up-regulating the expression and increasing enzymatic activity of 3β-hydroxysteriod dehydrogenoase (3β-HSD), which converts pregnenolone to P. WHAT IS KNOWN ALREADY Serum P level may rise prematurely prior to ovulation trigger in stimulated IVF cycles and adversely affect implantation and clinical pregnancy rates by impairing endometrial receptivity. STUDY DESIGN, SIZE, DURATION A translational research study. PARTICIPANTS/MATERIALS, SETTING, METHODS Human ovarian cortical samples (n = 15) and non-luteinizing FSH-responsive human mitotic granulosa cell line (HGrC1) were stimulated with rec-FSH at 12.5, 25 and 50 mIU/ml concentrations for 24 and 48 h. FSH receptor expression was knocked-down and up-regulated in the granulosa cells using short hairpin RNA (shRNA) technology and activin-A administration, respectively. The expressions of the steroidogenic enzymes were analyzed at mRNA level by real-time quantitative RT-PCR, and protein level by western blot and immunoprecipitation assay. The enzymatic activity of 3β-HSD was measured using a spectrophotometric method. In vitro estradiol (E2) and P productions of the cells before and after FSH stimulation were measured by electro-chemiluminescence immunoassay method. MAIN RESULTS AND THE ROLE OF CHANCE Stimulation of the HGrC1 cells with FSH resulted in a dose-dependent increase in the mRNA and protein level of 3β-HSD. Overall, when all time points and FSH doses were analyzed collectively, FSH significantly up-regulated the mRNA expression of its own receptor (3.73 ± 0.06-fold, P 0.05) did not significantly change. Similar changes were observed in the protein expression analysis of these enzymes on western blotting after FSH stimulation. FSH significantly increased 3β-HSD, 17β-HSD and aromatase in a dose-dependent manner but did not affect 17α-OH. Protein expression of P was increased along with 3β-HSD after FSH stimulation, which was further evidenced by immunoprecipitation assay. Enzymatic activity of 3β-HSD was significantly enhanced by FSH administration in the HGrC1 cells in a dose-dependent manner. In line with these findings P output (1.05 ± 0.3 vs. 0.2 ± 0.1 ng/ml, respectively, P < 0.001) from the samples stimulated with FSH were significantly increased along with E2 (1918 ± 203 vs. 932 ± 102 pg/ml, respectively, P < 0.001) compared to unstimulated controls. FSH-induced increase in 3β-HSD expression was amplified and reversed in the HGrC1 cells when FSH receptor expression was up-regulated by activin-A and down-regulated with shRNA, respectively. LIMITATIONS AND REASONS FOR CAUTION As only the effect of FSH was studied we cannot extrapolate our findings to the potential effects of HMG and recombinant LH. WIDER IMPLICATIONS OF THE FINDINGS This data provides a molecular explanation for the largely unexplained phenomenon of P rise during the follicular phase of gonadotropin stimulated IVF cycles. Our findings may progress the research to uncover potential mechanisms for preventing premature P rise that appears to be associated with inferior outcomes in women undergoing IVF. STUDY FUNDING/COMPETING INTEREST(S) Funded by the School of Medicine and the Graduate School of Health Sciences of Koc University. All authors declare no conflict of interest. TRIAL REGISTRATION NUMBER None.
71 citations
TL;DR: Test in mice the potential therapeutic use of pregnenolone against acute psychotic-like effects of Δ9-tetrahydrocannabinol, the main psychoactive component of cannabis found that it blocks a wide spectrum of THC-induced endophenotypes typically associated with psychotic- like states, including impairments in cognitive functions, somatosensory gating and social interaction.
Abstract: Cannabis-induced acute psychotic-like states (CIAPS) represent a growing health issue, but their underlying neurobiological mechanisms are poorly understood. The use of antipsychotics and benzodiazepines against CIAPS is limited by side effects and/or by their ability to tackle only certain aspects of psychosis. Thus, safer wide-spectrum treatments are currently needed. Although the blockade of cannabinoid type-1 receptor (CB1) had been suggested as a therapeutical means against CIAPS, the use of orthosteric CB1 receptor full antagonists is strongly limited by undesired side effects and low efficacy. The neurosteroid pregnenolone has been recently shown to act as a potent endogenous allosteric signal-specific inhibitor of CB1 receptors. Thus, we tested in mice the potential therapeutic use of pregnenolone against acute psychotic-like effects of Δ9-tetrahydrocannabinol (THC), the main psychoactive component of cannabis. We found that pregnenolone blocks a wide spectrum of THC-induced endophenotypes typically associated with psychotic-like states, including impairments in cognitive functions, somatosensory gating and social interaction. In order to capture THC-induced positive psychotic-like symptoms (e.g. perceptual delusions), we adapted a behavioral paradigm based on associations between different sensory modalities and selective devaluation, allowing the measurement of mental sensory representations in mice. Acting at hippocampal CB1 receptors, THC impaired the correct processing of mental sensory representations (reality testing) in an antipsychotic- and pregnenolone-sensitive manner. Overall, this work reveals that signal-specific inhibitors mimicking pregnenolone effects can be considered as promising new therapeutic tools to treat CIAPS.
50 citations
TL;DR: The data suggest that miR-132 attenuates steroidogenesis by repressing StAR expression and inducing 20 α-HSD via inhibition of MeCP2 to generate a biologically inactive 20α-OHP.
Abstract: miR-132 is hormonally regulated in steroidogenic cells of the adrenal gland, ovary and testis. Here, we examined the potential role of miR-132 in the control of steroidogenesis. Transfection of Y1 adrenal cells with miR-132 increased mRNAs of 3β-HSD and 20α-HSD enzymes, which catalyze the sequential conversion of pregnenolone to progesterone to biologically inactive 20α-hydroxyprogesterone (20α-OHP). Overexpression of miR-132 reduced MeCP2 and StAR protein expression, basal progestin (progesterone and 20α-OHP) production, but enhanced their production in response to cAMP stimulation. Use of [3H] pregnenolone and free-diffusible 22(R)-hydroxycholesterol further confirmed that miR-132 promotes the production of 20α-OHP by upregulating 3β-HSD and 20α-HSD. Evidence is also presented that StAR is a direct target of miR-132. Transient transfection of Y1 cells with miR-132 demonstrated that miR-132 induction of 3β-HSD and 20α-HSD was accompanied by significant suppression of one of its target gene products, MeCP2. In contrast, co-expression of miR-132 plus MeCP2 protein partially blocked the ability of miR-132 to upregulate the expression and function of 3β-HSD and 20α-HSD. Moreover, suppression of MeCP2 protein with siRNA resulted in increased expression of 3β-HSD and 20α-HSD, further demonstrating that miR-132 induces the expression of these two enzymes via inhibition of MeCP2. Likewise, overexpression of miR-132 increased 20α-OHP production with and without HDL loading, while knockdown of miR-132 resulted in a significant decrease of 20α-OHP production by granulosa cells. In conclusion, our data suggest that miR-132 attenuates steroidogenesis by repressing StAR expression and inducing 20α-HSD via inhibition of MeCP2 to generate a biologically inactive 20α-OHP.
38 citations
TL;DR: The results suggest multiple conformations of P450 17A1, as previously proposed on the basis of NMR spectroscopy and X-ray crystallography, and Global kinetic modeling helped assign sets of rate constants for individual or groups of reactions, indicating that human P45017A1 is an inherently distributive enzyme but that some processivity is present.
36 citations
TL;DR: A method for the quantitation of 22 urinary steroids by means of gas chromatography tandem mass spectrometry using a triple quadrupole analyzer has been developed and was shown to be linear in the range of endogenous concentrations for all studied steroids with extraction recoveries higher than 80%.
36 citations
TL;DR: It is found that D4G inhibits steroidogenesis and suppresses AR protein stability, AR target gene expression, and xenograft growth comparably with galeterone, and further conversion by SRD5A leads to loss of several activities that inhibit the androgen axis that may compromise clinical efficacy.
36 citations
TL;DR: Findings point to multiple defects in peripheral steroidogenesis associated with and potentially relevant to PCDH19‐FE, and some of these defects could be addressed by stimulating adrenocortical activity.
Abstract: Patients affected by protocadherin 19 (PCDH19)-female limited epilepsy (PCDH19-FE) present a remarkable reduction in allopregnanolone blood levels. However, no information is available on other neuroactive steroids and the steroidogenic response to hormonal stimulation. For this reason, we evaluated allopregnanolone, pregnanolone, and pregnenolone sulfate by liquid chromatographic procedures coupled with electrospray tandem mass spectrometry in 12 unrelated patients and 15 age-matched controls. We also tested cortisol, estradiol, progesterone, and 17OH-progesterone using standard immunoassays. Apart from estradiol and progesterone, all the considered hormones were evaluated in basal condition and after stimulation with adrenocorticotropic hormone (ACTH). A generalized decrease in blood levels of almost all measured neuroactive steroids was found. When considering sexual development, cortisol and pregnenolone sulfate basal levels were significantly reduced in postpubertal girls affected by PCDH19-FE. Of interest, ACTH administration did not recover pregnenolone sulfate serum levels but restored cortisol to control levels. In prepubertal girls with PCDH19-FE, by challenging adrenal function with ACTH we disclosed defects in the production of cortisol, pregnenolone sulfate, and 17OH-progesterone, which were not apparent in basal condition. These findings point to multiple defects in peripheral steroidogenesis associated with and potentially relevant to PCDH19-FE. Some of these defects could be addressed by stimulating adrenocortical activity.
35 citations
TL;DR: It is demonstrated that CDKL5 is required for IQGAP1 to form a functional complex with its effectors, Rac1 and the microtubule plus end tracking protein CLIP170, so as to pave the way for target-specific therapeutic strategies for individuals affected with CDkL5-disorder.
Abstract: CDKL5 is a protein kinase that plays a key role for neuronal functions as testified by the onset of complex neuronal dysfunctions in patients with genetic lesions in CDKL5. Here we identify a novel interactor of CDKL5, IQGAP1, a fundamental regulator of cell migration and polarity. In accordance with a functional role of this interaction, depletion of CDKL5 impairs cell migration and impedes the localization of IQGAP1 at the leading edge. Moreover, we demonstrate that CDKL5 is required for IQGAP1 to form a functional complex with its effectors, Rac1 and the microtubule plus end tracking protein CLIP170. These defects eventually impact on the microtubule association of CLIP170, thus deranging their dynamics. CLIP170 is a cellular target of the neurosteroid pregnenolone; by blocking CLIP170 in its active conformation, pregnenolone is capable of restoring the microtubule association of CLIP170 in CDKL5 deficient cells and rescuing morphological defects in neurons devoid of CDKL5. These findings provide novel insights into CDKL5 functions and pave the way for target-specific therapeutic strategies for individuals affected with CDKL5-disorder.
32 citations
22 May 2017
TL;DR: It is found that as gliomas became more malignant, both CYP17A1 and DHEA were significantly upregulated in temozolomide-resistant cells and highly invasive cells, and components of the Sp1-mediated DNA demethylation axis, which promotes the development of TMZ resistance, may serve as potential biomarkers and therapeutic targets in recurrent glioma.
Abstract: Steroidogenesis-mediated production of neurosteroids is important for brain homeostasis. Cytochrome P450 17A1 (CYP17A1), which converts pregnenolone to dehydroepiandrosterone (DHEA) in endocrine organs and the brain, is required for prostate cancer progression and acquired chemotherapeutic resistance. However, whether CYP17A1-mediated DHEA synthesis is involved in brain tumor malignancy, especially in glioma, the most prevalent brain tumor, is unknown. To investigate the role of CYP17A1 in glioma, we determined that CYP17A1 expression is significantly increased in gliomas, which secrete more DHEA than normal astrocytes. We found that as gliomas became more malignant, both CYP17A1 and DHEA were significantly upregulated in temozolomide (TMZ)-resistant cells and highly invasive cells. In particular, the increase of CYP17A1 was caused by Sp1-mediated DNA demethylation, whereby Sp1 competed with DNMT3a for binding to the CYP17A1 promoter in TMZ-resistant glioma cells. CYP17A1 was required for the development of glioma cell invasiveness and resistance to TMZ-induced cytotoxicity. In addition, DHEA markedly attenuated TMZ-induced DNA damage and apoptosis. Together, our results suggest that components of the Sp1-CYP17A1-DHEA axis, which promotes the development of TMZ resistance, may serve as potential biomarkers and therapeutic targets in recurrent glioma.
TL;DR: The results indicate a gain of free steroid from circulating steroid sulphates as hormone precursors at the blood–brain barrier, with implications for ageing, neurogenesis, neuronal survival, learning and memory.
Abstract: Little is known about the origin of the neuroactive steroids dehydroepiandrosterone sulphate (DHEAS) and pregnenolone sulphate (PregS) in the brain or of their subsequent metabolism. Using rat brain perfusion in situ, we have found (3) H-PregS to enter more rapidly than (3) H-DHEAS and both to undergo extensive (>50%) desulphation within 0.5 min of uptake. Enzyme activity for the steroid sulphatase catalysing this deconjugation was enriched in the capillary fraction of the blood-brain barrier and its mRNA expressed in cultures of rat brain endothelial cells and astrocytes. Although permeability measurements suggested a net efflux, addition of the efflux inhibitors GF120918 and/or MK571 to the perfusate reduced rather than enhanced the uptake of (3) H-DHEAS and (3) H-PregS; a further reduction was seen upon the addition of unlabelled steroid sulphate, suggesting a saturable uptake transporter. Analysis of brain fractions after 0.5 min perfusion with the (3) H-steroid sulphates showed no further metabolism of PregS beyond the liberation of free steroid pregnenolone. By contrast, DHEAS underwent 17-hydroxylation to form androstenediol in both the steroid sulphate and the free steroid fractions, with some additional formation of androstenedione in the latter. Our results indicate a gain of free steroid from circulating steroid sulphates as hormone precursors at the blood-brain barrier, with implications for ageing, neurogenesis, neuronal survival, learning and memory. This article is protected by copyright. All rights reserved.
TL;DR: Of all fungicides tested at 100 µmol/L, only TBT inhibited pregnenolone-mediated progesterone production in JEG-3 cells by over 50%.
Abstract: Placenta secretes a large amount of progesterone and estradiol, which are critical for maintaining pregnancy. In human placenta, 3β-hydroxysteroid dehydrogenase 1 (HSD3B1) catalyzes pregnenolone to form progesterone, and aromatase (CYP19A1) catalyzes testosterone into estradiol. Fungicides display antifungal activities and are widely used to prevent fungal infections in agricultural plants. These chemicals include azoles, such as tebuconazole (TEB), triadimefon (TRI), and vinclozolin (VCZ) or organotins, such as tributyltin (TBT) and tetrabutyltin (TTBT). Fungicides may disrupt the activities of these 2 enzymes. In the present study, we investigated the effects of these fungicides on steroid production in a human placental cell line JEG-3 and on HSD3B1 and CYP19A1 activities. Of all fungicides tested at 100 µmol/L, only TBT inhibited pregnenolone-mediated progesterone production in JEG-3 cells by over 50%. Except TTBT, all other 4 fungicides inhibited testosterone-mediated estradiol production by over 50%. TBT was a moderate HSD3B1 inhibitor with a half maximal inhibitory concentration (IC50) of 45.60 ± 0.12 µmol/L. When pregnenolone was used to determine the mode of inhibition, TBT was a competitive inhibitor of HSD3B1. The IC50 values of TEB, TRI, VCZ, and TBT for CYP19A1 were 56.84 ± 0.13, 58.73 ± 0.14, 57.42 ± 0.171, and 4.58 ± 0.048 µmol/L, respectively. TEB, TRI, and VCZ were noncompetitive inhibitors of CYP19A1, while TBT was a competitive inhibitor of this enzyme. Therefore, they are endocrine disruptors.
TL;DR: It is suggested that adrenal steroids upregulated by etifoxine make an important contribution to the steroids present in brain, and this work provides a precise and complete view of steroids regulated by et ifoxine that could be useful in therapeutic research.
TL;DR: The high sensitivity and the quantitative aspect of the method permitted to detect most of the steroids in equine serum and was used to quantify 17 steroid hormones in mare, stallion and gelding serum samples.
Abstract: A new, fast and simple analytical method that is able to identify and quantify simultaneously 17 steroid hormones and metabolites (pregnenolone, 17-OH-pregnenolone, progesterone, 17-OH-progesterone, androsterone, androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, testosterone, cortisol, corticosterone, aldosterone, 11-deoxycortisol, 11-deoxycorticosterone, dihydrotestosterone, estrone and estradiol) has been developed in equine serum using the ultra-high-performance liquid chromatography-tandem mass spectrometry technique A total of 400 µl of sample was deproteinized with 1000 µl of acetonitrile, evaporated, restored with 50 µl of a solution of 25% methanol and injected in ultra-high-performance liquid chromatography-tandem mass spectrometry triple quadrupole The recovery percentage obtained by spiking the matrix at two different concentrations with a standard mixture of steroid hormones was in all cases higher than 8560% and with the percentage of coefficient of variation lower than 837% The range of the correlation coefficients of the calibration curves of the analyzed compounds was 09922-09986, and the limits of detection and limits of quantification were in the range of 0002-2 and 00055-55 ng ml-1 , respectively The detected limit of quantification for testosterone (ie 50 pg ml-1 ) is twofold lower with respect to its threshold admitted in geldings plasma (100 pg ml-1 free testosterone) The high sensitivity and the quantitative aspect of the method permitted to detect most of the steroids in equine serum Once validated, the method was used to quantify 17 steroid hormones in mare, stallion and gelding serum samples The main steroids detected were corticosterone (range 3725-5126 ng ml-1 ) and cortisol (range 3257-5224 ng ml-1 ), followed by 17-OH-pregnenolone, dihydrotestosterone and pregnenolone Copyright © 2016 John Wiley & Sons, Ltd
TL;DR: The adrenal steroid and steroid precursor response to disease and their association with the HPAA response to illness, disease severity, and mortality in hospitalised foals were characterised.
Abstract: Hypothalamic–pituitary–adrenal axis (HPAA) dysfunction has been associated with sepsis and mortality in foals Most studies have focused on cortisol, while other steroids have not been investigated The objectives of this study were to characterise the adrenal steroid and steroid precursor response to disease and to determine their association with the HPAA response to illness, disease severity, and mortality in hospitalised foals All foals (n = 326) were classified by two scoring systems into three categories: based on the sepsis score (septic, sick non-septic [SNS] and healthy) and the foal survival score (Group 1: 3–18%; Group 2: 38–62%; Group 3: 82–97% likelihood of survival) Blood concentrations of adrenocorticotropic hormone (ACTH) and steroids were determined by immunoassays ACTH–cortisol imbalance (ACI) was defined as a high ACTH/cortisol ratio Septic foals had higher ACTH, cortisol, progesterone, 17α-OH-progesterone, pregnenolone, and androstenedione concentrations as well as higher ACTH/cortisol, ACTH/progesterone, ACTH/aldosterone, and ACTH/DHEAS ratios than SNS and healthy foals (P In addition to cortisol, the response to the stress of illness in foals is characterised by the release of multiple adrenal steroids DHEAS and progesterone were good predictors of HPAA dysfunction and outcome in hospitalised foals
TL;DR: The investigated the pharmacological effects of PSNCBAM-1 and two structural analogs, RTICBM-15 and -28, as well as pregnenolone, in both signaling and behavioral assays including [35S]GTPγS binding, the cannabinoid tetrad and drug discrimination, and confirmed the established pharmacology ofPSNCB AM and analogs in molecular assays of CB1 receptor function.
TL;DR: Data obtained indicate that short-term diabetes alters hippocampal steroidogenic machinery and that these changes are associated with impaired cholesterol homeostasis and mitochondrial dysfunction in the hippocampus, suggesting them as relevant factors for the development of diabetic encephalopathy.
TL;DR: Dietary supplementation of pentaacetylquercetin could be potentially effective to maintain testosterone production within aging males using supplementation with flavonoids, a group of the polyphenolic compounds widely distributed in fruits and vegetables.
TL;DR: Induction of a ROS/p38 MAPK -mediated feedback inhibitory pathway by oxy-cholesterol and steroid intermediates and products attenuates steroidogenesis via inhibition of CREB transcriptional activity.
Abstract: Steroidogenesis is a complex, multi-steps biological process in which, cholesterol precursor is converted to steroids in a tissue specific and tropic hormone dependent manner. Given that steroidogenesis is achieved by coordinated functioning of multiple tissue specific enzymes, many steroids intermediates/metabolites are generated during this process. Both the steroid products as well as major lipoprotein cholesterol donor, high-density lipoprotein 3 (hHDL3) have the potential to negatively regulate steroidogenesis via increased oxidative stress/reactive oxygen species (ROS) generation. In the current study, we examined the effects of treatment of a mouse model of steroidogenesis, Y1-BS1 adrenocortical tumor cells with pregnenolone, 22(R)-Hydroxycholesterol [22(R)-diol] or hHDL3 on ROS production, phosphorylation status of p38 MAPK and cAMP response element-binding protein (CREB), CREB transcriptional activity and mRNA expression of StAR, CPY11A1/P450scc and antioxidant enzymes, superoxide dismutases [Cu,ZnSOD (SOD1), MnSOD (SOD2)], catalase (CAT) and glutathione peroxidase 1 (GPX1). We also detected the steroid product in p38 MAPK inhibitor treated Y1 cells by HPLC-MS / MS. Treatment of Y1 cells with H2O2 greatly enhanced the phosphorylation of both p38 MAPK and CREB protein. Likewise, treatment of cells with pregnenolone, 22(R) diol or hHDL3 increased ROS production measured with the oxidation-sensitive fluorescent probe 2′,7′-Dichlorofluorescin diacetate (DCFH-DA). Under identical experimental conditions, treatment of cells with these agents also increased the phosphorylation of p38 MAPK and CREB. This increased CREB phosphorylation however, was associated with its decreased transcriptional activity. The stimulatory effects of pregnenolone, 22(R)-diol and hHDL3 on CREB phosphorylation was abolished by a specific p38 MAPK inhibitor, SB203580. Pregnenolone, and 22(R) diol but not hHDL3 upregulated the mRNA expression of SOD1, SOD2 and GPX1, while down-regulated the mRNA levels of StAR and CYP11A1. The p38 inhibitor SB203580 could increase the steroid production in HDL3, 22(R)-diol or pregnenolone treated cells. Our data demonstrate induction of a ROS/p38 MAPK -mediated feedback inhibitory pathway by oxy-cholesterol and steroid intermediates and products attenuates steroidogenesis via inhibition of CREB transcriptional activity.
TL;DR: In both naïve and neuropathic rats, in vivo stereotaxic microinjection of PK 11195, the translocator protein inhibitor, into the ventral hippocampus exacerbated anxiety‐like behaviors, indicating anxiolytic effects of hippocampal neurosteroids in both normal and neuropathy rats.
Abstract: Neurosteroids are synthesized in the nervous system from cholesterol or steroidal precursors imported from peripheral sources. These compounds are important allosteric modulators of GABAA receptors, which play a vital role in modulating hippocampal functions. Chronic pain is accompanied by increased neurosteroid production in the spinal cord and thalamus. We hypothesize that hippocampal neurosteroids participate in pain or pain-associated emotions, which we tested with high-performance liquid chromatography/tandem mass spectrometry and pharmacological behavioral tests. We observed increased levels of hippocampal neurosteroids (pregnenolone, progesterone, deoxycorticosterone, and allopregnanolone) in rats with chronic neuropathic pain (28 days after spared nerve injury). Meanwhile, the expression of the translocator protein, the upstream steroidogenesis rate-limiting enzyme, increased in the ventral but not dorsal hippocampus of neuropathic rats. In both naive and neuropathic rats, in vivo stereotaxic microinjection of PK 11195, the translocator protein inhibitor, into the ventral hippocampus exacerbated anxiety-like behaviors. These results indicate anxiolytic effects of hippocampal neurosteroids in both normal and neuropathic rats. Neurosteroids could be considered as agents for treatment of general and pain-related anxiety disorders.
TL;DR: It is demonstrated that stress leads to the alteration of the GABAergic neurosteroid profile in rats, and this results will be helpful for furthering an understanding of the role of neurosteroids in stressed conditions.
TL;DR: Among all four active compounds, the novel compound 3a has shown significant bone matrix mineralization and mRNA expressions of osteogenic marker genes, BMP2, RUNX-2 and OCN at 1pM concentration.
TL;DR: The present study suggests that sustentacular cells and acinar cells of the Bowman's glands in the rat OM express at least three of the steroid‐metabolizing enzymes, that is, P450scc 17β‐HSD‐1, and 17 β‐ HSD‐2, and de novo synthesis of estradiol takes place in the OM.
Abstract: Although several lines of evidence have suggested that sex steroids influence olfaction, little is known about the cellular basis of steroid-metabolizing enzymes in the olfactory system. Thus, we aimed to examine gene expression and immunolocalization of four sex steroid-metabolizing enzymes in the olfactory mucosa (OM) of albino rats; steroid side chain-cleaving enzyme (P450scc), 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD-1), 17β-HSD type 2 (17β-HSD-2), and aromatase. P450scc is known to catalyze conversion from cholesterol to pregnenolone. 17β-HSD-1 catalyzes conversion from estrone to estradiol, and 17β-HSD-2 does the reverse. Aromatase catalyzes the conversion from testosterone to estradiol-17β. Messenger (m) RNAs of all four enzymes mentioned above were detected in the OM. Western blot analysis demonstrated that P450scc, 17β-HSD-1, and 17β-HSD-2 were detected in the OM. Immunoreactivity for these three enzymes was observed in sustentacular cells of the olfactory epithelium and acinar cells of Bowman's glands. Immunoelectron microscopy analysis demonstrated immunoreactivity for P450scc in mitochondria, and for 17β-HSD-1 and 17β-HSD-2 in the well-developed smooth endoplasmic reticulum and myeloid bodies of the sustentacular cells. The present study suggests that sustentacular cells and acinar cells of the Bowman's glands in the rat OM express at least three of the steroid-metabolizing enzymes, that is, P450scc 17β-HSD-1, and 17β-HSD-2, and de novo synthesis of estradiol takes place in the OM. Anat Rec, 300:402-414, 2017. © 2016 Wiley Periodicals, Inc.
TL;DR: The present study indicated that pregnenolone/2-cyanoacryloyl conjugate I can server as a novel scaffold for developing NF-κB inhibitors and anti-proliferative agents in cancer chemotherapy.
TL;DR: It is indicated that PCN has unexpected immunosuppressive activity independent of PXR activation to protect mice from immune-mediated liver injury induced by concanavalin A (Con A), a model of immune- mediated liver injury, using wild-type and Pxr-/- mice.
TL;DR: The findings suggest that neurosteroids may be associated with gender differences in susceptibility to schizophrenia.
TL;DR: It is suggested that CYP2D6 polymorphism would affect drug interaction through dopamine formation in the brain through inhibition constants or 50% inhibitory concentrations of six steroid hormones.
TL;DR: The results suggest that IH in rats increases the secretion of corticosterone via a mechanism at least in part associated with the activation of cAMP pathway and steroidogenic enzymes.
Abstract: Hypoxia or intermittent hypoxia (IH) have known to alter both synthesis and secretion of hormones. However, the effect of IH on the production of adrenal cortical steroid hormones is still unclear. The aim of present study was to explore the mechanism involved in the effect of IH on the production of corticosterone by rat ZFR cells. Male rats were exposed at 12% O2 and 88% N2 (8 hours per day) for 1, 2, or 4 days. The ZFR cells were incubated at 37 °C for 1 hour with or without ACTH, 8-Br-cAMP, calcium ion channel blockers, or steroidogenic precursors. The concentration of plasma corticosterone was increased time-dependently by administration of IH hypoxia. The basal levels of corticosterone production in cells were higher in the IH groups than in normoxic group. IH resulted in a time-dependent increase of corticosterone production in response to ACTH, 8-Br-cAMP, progesterone and deoxycorticosterone. The production of pregnenolone in response to 25-OH-C and that of progesterone in response to pregnenolone in ZFR cells were enhanced by 4-day IH. These results suggest that IH in rats increases the secretion of corticosterone via a mechanism at least in part associated with the activation of cAMP pathway and steroidogenic enzymes.
TL;DR: Findings suggest possible differences in serum MAP2 levels between bipolar depressed persons and controls and a relationship between changes in depressive symptoms and MAP-2 levels during pregnenolone therapy and additional research is needed onMAP-2 in mood disorders.