Major Steroid Research Articles

A Narrative Role of Vitamin D and Its Receptor: With Current Evidence on the Gastric Tissues.

Vitamin D is a major steroid hormone that is gaining attention as a therapeutic molecule. Due to the general awareness of its importance for the overall well-being, vitamin D deficiency (VDD) is now recognized as a major health issue. The main reason for VDD is minimal exposure to sunlight. The vitamin D receptor (VDR) is a member of the steroid hormone receptors that induces a cascade of cell signaling to maintain healthy Ca2+ levels that serve to regulate several biological functions. However, the roles of vitamin D and its metabolism in maintaining gastric homeostasis have not yet been completely elucidated. Currently, there is a need to increase the vitamin D status in individuals worldwide as it has been shown to improve musculoskeletal health and reduce the risk of chronic illnesses, including some cancers, autoimmune and infectious diseases, type 2 diabetes mellitus, neurocognitive disorders, and general mortality. The role of vitamin D in gastric homeostasis is crucial and unexplored. This review attempts to elucidate the central role of vitamin D in preserving and maintaining the overall health and homeostasis of the stomach tissue.

Age and Sex-Related Changes to Gene Expression in the Mouse Spinal Cord.

The spinal cord is essential for neuronal communication between the brain and rest of the body. To gain further insight into the molecular changes underpinning maturation of the mouse spinal cord, we analysed gene expression differences between 4weeks of age (prior to puberty onset) and adulthood (8weeks). We found 800 genes were significantly differentially expressed between juvenile and adult spinal cords. Gene ontology analysis revealed an overrepresentation of genes with roles in myelination and signal transduction among others. The expression of a further 19 genes was sexually dimorphic; these included both autosomal and sex-linked genes. Given the presence of steroid hormone receptors in the spinal cord, we also looked at the impact of two major steroid hormones, oestradiol and dihydrotestosterone (DHT) on spinal cord gene expression for selected genes. In gonadectomised male animals, implants with oestradiol and DHT produced significant changes to spinal cord gene expression. This study provides an overview of the global gene expression changes that occur as the spinal cord matures, over a key period of maturation. This confirms that both age and sex are important considerations in studies involving the spinal cord.

Progesterone induced Warburg effect in HEK293 cells is associated with post-translational modifications and proteasomal degradation of progesterone receptor membrane component 1

Progesterone (P4) is a major steroid hormone that has important effects on metabolism. The progesterone receptor membrane component 1 (PGRMC1) is a non-canonical P4 binding protein. The biological functions affected by PGRMC1 include cholesterol/steroid biosynthesis and metabolism, iron homeostasis and heme trafficking, autophagy, regulation of cell cycle and proliferation, cell migration and invasion. PGRMC1 has been an attractive target for therapeutic intervention in cancer and neurodegenerative disorders due to its biological role in promoting cell survival. P4 has been used in a number of clinical applications and is considered neuroprotective. The involvement of PGRMC1 in P4-mediated regulation of cellular glucose metabolism is not well studied. PGRMC1 is a 21 kDa protein but complex post-translational modifications (PTMs) lead to the existence of several high molecular mass proteins whose molecular function, intracellular distribution, and physiological relevancies are not fully known. Therefore, in this study, P4-PGRMC1-mediated cellular glucose metabolism and PTMs of PGRMC1 were studied using wild-type and CRISPR/Cas9 mediated PGRMC1 knockout (KO) human embryonic kidney-derived (HEK293) cell lines. A 70 kDa (p70) and 100 kDa (p100) PGRMC1 proteins were identified that are predominantly associated with endoplasmic reticulum/mitochondria and nuclear fractions in the cells, respectively. Phosphorylation, acetylation, ubiquitination, and sumoylation of native PGRMC1 under serum starvation were identified which provided an explanation for the higher molecular masses. This study indicates that P4-PGRMC1 signaling caused a rapid increase in glycolysis in the presence of oxygen (aerobic glycolysis) and a corresponding decrease in cellular respiration, known as the Warburg effect. Further, it was demonstrated that the P4-induced increase in glycolysis is associated with rapid proteasomal degradation of the p70 and reduction of the nuclear p100 protein level. P4 treatment also caused significant alteration in the dynamics of PGRMC1 PTMs and its association with potential interacting proteins. Overall, this study provides a hitherto unknown aspect of P4-PGRMC1 mediated signaling that changes basic cellular metabolism in HEK293 cells.

Measuring the structural impact of mutations on cytochrome P450 21A2, the major steroid 21-hydroxylase related to congenital adrenal hyperplasia

Congenital adrenal hyperplasia is an inherited autosomal recessive disorder related to deficient cortisol synthesis. The deficiency of steroid 21-hydroxylase (cytochrome P450 21A2), an enzyme involved in cortisol synthesis, is responsible for ∼95% of cases of congenital adrenal hyperplasia. This metabolic disease exhibits three clinical forms: salt-wasting, simple virilizing, and non-classical form, which are divided according to the degree of severity. In the present study, structural and mutational analyses were performed in order to identify the structural impact of mutations on cytochrome P450 21A2 and correlate them with patient clinical severity. The following mutations were selected: arginine-356 to tryptophan (R356W), proline-30 to leucine (P30L), isoleucine-172 to asparagine (I172N), valine-281 to leucine (V281L), and the null mutation glutamine-318 (Q318X). Our computational approach mapped the location of residues on P450 and identified their implications on enzyme electrostatic potential mapping to progesterone and heme binding pockets. Using molecular dynamics simulations, we analyzed the structural stability of ligand binding and protein structure, as well as possible conformational changes at the catalytic pocket that leads to impairment of enzymatic activity. Our study sheds light on the impact structural mutations have over steroid 21-hydroxylase structure-function in the cell.Communicated by Ramaswamy H. Sarma

Modulation of NHE3 Activity in Rat Renal Proximal Tubules during the Estrous Cycle Phases and Direct Impact of Estradiol and Progesterone

Estradiol (E2) and progesterone (P4) are two of the major steroid hormones involved in the control of reproductive functions in females. Among other effects, E2 and P4 can modulate sodium reabsorption along the nephron, altering the hydroelectrolytic balance, leading to hydrosaline retention. Na/H exchanger, isoform 3, is the main route for sodium bicarbonate reabsorption in renal proximal tubules (PT). The aims of the present study are to evaluate the activity of NHE3 in the different estrous cycle phases and to investigate the direct effects of E2 and P4 on NHE3 activity in kidneys of control (sham) or ovariectomized rats (OVX). All the protocols were approved by the Committee on Animal Research and Ethics from the Ceara State University (protocol #2722214/2016). The estrous cycle of female Wistar rats were evaluated during 15 days and animals randomly assigned to OVX or sham group. Thereafter, two weeks after surgery, the activity of NHE3 was evaluated in vivo by using the stationary microperfusion (SM) technique and after this procedure, the kidneys were stored for evaluation of NHE3 protein abundance by Western Blot (WB). In a first set of experiments, PT were punctured to perfuse control solution (PCS) in order to compare the different phases of the estrous cycle against OVX‐group. In a second set, PTs were perfused with E2 or P4 to compare with OVX animals. SM allows the measurement of H+ secretion in proximal tubules, representing an indirect measure of NHE3 function. It was observed that OVX presented lower H+ secretory activity than all cyclic groups and the estrous group presented higher secretion rates: [JHCO3‐ nmol.cm‐2.s‐1 OVX 1.74 ± 0.07 (10); Proestrus 1.90 ± 0.12 (12)a; Estrus 2.35 ± 0.08 (13)ab; Metaestrus 1.97 ± 0.12 (15)ac and Diestrus 1.89 ± 0.08 (14)ac, where a p <0.05 vs OVX, b p <0.05 vs Proestrus and c p <0.05 vs Estrus]. In addition, an increase in proximal H+ secretion/bicarbonate reabsorption was observed in all E2 and P4 concentrations when administered intratubularly and compared to the OVX group: [JHCO3‐, nmol.cm‐2s‐ OVX+Vehicle 1.84 ± 0.06 (11); E2 (0.1 nM) 2.18 ± 0.07 (15)a; E2 (1 nM) 2.24 ± 0.08 (11)a; E2 (10 nM) 2.20 ± 0.09 (12)a; P4 (0.1 nM), 2.18 ± 0.11 (13)a, P4 (10 nM), 2.10 ± 0.07 (10)a, where a p <0.05 vs OVX + Vehicle]. NHE3 total/villin expression in brush border membranes of PT is lower in the Diestrus group when compared to all other groups: OVX 0.79 ± 0.26 (n=5); Proestrus 0.64 ± 0.08 (n=6); Estrus 0.76 ± 0.30 (n=6); Metaestrus 0.69 ± 0.12 (n=6); Diestrus 0.22 ± 0.12 (n=6)*, p <0.05 vs OVX, Proestrus, Estrus and Metaestrus. Significative changes in NHE3 activity occurs in the different phases of estrous cycles with higher activity in the estrus and lower in diestrus. In addition, it was observed a positive regulation of NHE3 by E2 and P4 in PT which may contribute to sodium retention if this stimulus is maintained for a long‐term.Support or Funding InformationCNPq/FUNCAPThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Pregnancy level of estradiol attenuated virus-specific humoral immune response in H5N1-infected female mice despite inducing anti-inflammatory protection

ABSTRACT Estradiol, a major female steroid produced during pregnancy, has been reported to protect ovariectomized animals against H1N1 influenza infections via its anti-inflammatory effects. However, it remains unclear why pregnant women with high gestational estradiol levels are highly susceptible to influenza infections. This study was aimed to investigate the effects of pregnancy level of estradiol on female immunity against H5N1 infection in Balb/c mice. A sex-dependent susceptibility to H5N1 infection (higher morbidity and higher mortality) was observed in both pregnant and non-pregnant female mice as compared to male mice. Subcutaneous implantation of estradiol pellets increased serum estradiol concentrations of non-pregnant female mice to the pregnancy level. These mice were protected from H5N1 infection through downregulation of pulmonary pro-inflammatory cytokines. However, the production of virus-specific antibodies after infection was significantly delayed in estradiol-implanted mice when compared to placebos. Virus-specific IgG-secreting and IL-4-secreting cells were also reduced in estradiol-implanted mice. Similarly, lower antibody titers to seasonal vaccine antigens were found in pregnant women as compared to non-pregnant females without hormone usage. Our results indicate that estradiol levels equivalent to those found during pregnancy have divergent effects on female immunity against influenza, highlighting the importance of vaccination during pregnancy to prevent severe influenza infections.

Ontogenesis of human fetal testicular steroidogenesis at early gestational age

The onset of steroidogenesis in human fetal testes (HFT) during the first trimester is poorly investigated. One important unresolved question is the ontogeny of steroidogenic enzymes and formation of steroidogenic pathways in the HFT at early pregnancy.Our aim was to explore steroidogenesis, the expression of steroidogenic enzymes and their maturation in the HFT at gestational weeks (GW) 8-12. Steroids in the HFT were analyzed by gas chromatography/coupled to tandem mass spectrometry. The expression of steroidogenic enzymes in the HFT at GW8-12 was investigated by qPCR, automated Western blotting and immunohistochemistry. We demonstrated that the HFT at GW8-9 produced low level of testosterone via the Δ4 pathway and progesterone was the major steroid found in the testicular tissue. In contrast, more mature Leydig cells from the HFT at GW11-12 synthesized high levels of androgens via the Δ5 pathway. We also observed a significant upregulation of the expression of StAR, CYP11A1, CYP17A1 and its accessory proteins, P450 oxidoreductase (POR) and cytochrome b5 in the HFT at GW11-12 compared to GW8-9.Altogether, our data suggest that that human fetal Leydig cells differentiate rapidly at the end of the first trimester by acquiring capacity to express high levels of steroidogenic enzymes and switch from the Δ4 to the Δ5 pathways to synthesize high levels of androgens due to maturation of the CYP17-POR-b5 complex.

Cuprizone-induced demyelination in the mouse hippocampus is alleviated by phytoestrogen genistein

One of the major female sex hormones, estrogen, can influence a variety of mental states. Individuals with multiple sclerosis (MS) often suffer from mental health issues, which are correlated with the pathology of gray matter. In this study, we aimed to elucidate the validity of phytoestrogen genistein (GEN) for treating the gray matter lesions in MS using the mouse model of cuprizone (CPZ)-induced demyelination. First, we confirmed that 5-week 0.2% CPZ intoxication induced demyelination in the hippocampus, and that myelination was successfully recovered by GEN. Loss of mature oligodendrocytes following CPZ intoxication was counteracted by GEN. Neither CPZ nor GEN affected the densities of oligodendrocyte precursor cells and astrocytes. CPZ-induced activation and proliferation of microglia were not inhibited by GEN. Upregulation of gene expression of the pro-inflammatory cytokine, interleukin-1β, in sorted microglia by CPZ was not inhibited by GEN either. However, the expression levels of genes related to phagocytosis, such as cluster of differentiation 68 and lysosomal-associated membrane protein 1, in sorted microglia were elevated by CPZ but lowered by GEN. Notably, physical contact of microglia with myelin was increased by CPZ but decreased by GEN. The expression levels of myelin-related genes, such as myelin basic protein and myelin oligodendrocyte glycoprotein, in the whole hippocampal tissue were decreased by CPZ but recovered by GEN. These results show that GEN may act on mature oligodendrocytes in the hippocampus by promoting their survival and myelin formation, and suggest the therapeutic potential of phytoestrogens for treating MS patients suffering from mental health issues.

Prolactin-Induced Protein is a novel biomarker for Keratoconus

PurposeThe purpose of the study was to investigate the role of Prolactin-Induced Protein (PIP) as a predictive biomarker for Keratoconus (KC). ParticipantsThis study included one hundred and forty-seven patients with KC (105 male, 42 female), and sixty healthy controls (27 male, 33 female). MethodsTears, plasma and saliva samples were collected from all participants. In both KC and healthy groups all collected samples were divided into four age subgroups (15-24y), (25-34y), (35-44y) and (45y and up). Samples were analyzed using western blot (WB) and enzyme-linked immunosorbent assay (ELISA). Areas under the receiver operating characteristic curves (AUROCs) were used to evaluate diagnostic accuracy for distinguishing between KC and healthy eyes. Main outcome measuresDifference in PIP protein levels between patients with KC and healthy controls. ResultsResults showed significant downregulation of PIP expression in all three biological fluids on KC patients when compared to healthy controls, independent of age, sex and severity. Since PIP is a hormonal-regulated protein, we also investigated the expression of major sex hormones. We detected significant upregulation in salivary and plasma Dehydroepiandrosterone sulfate (DHEA-S) levels and significant downregulation of estrone and estriol levels, in KC patients compared to healthy controls, independent of sex, age, and KC severity stage. ROC was used to determine the overall predictive accuracy of this protein in KC. Data showed an area under the curve (AUC) for PIP in tears of 0.937 (95%CI: 0.902–0.971), in plasma of 0.928 (95%CI: 0.890–0.968) and in saliva of 0.929 (95%CI: 0.890–0.968). ConclusionsConclusively, our results show that PIP levels are reduced in all three human biological fluids tested, and may independently or in combination with current imaging techniques aid in screening and diagnosis of KC. Our data revealed that PIP levels can potentially differentiate between disease and healthy cases, and PIP levels are stable in relation to KC severity, sex and age. Moreover, alterations in sex hormone levels in correlation with reduced PIP levels in KC provide an intriguing insight in the underlying KC pathophysiology and highlights the role of PIP as a KC biomarker.

Insulin-like peptide 3 (INSL3) is a major regulator of female reproductive physiology.

Insulin-like peptide 3 (INSL3) is a member of the relaxin family of neohormones which has evolved to address specifically mammalian aspects of reproduction related to viviparity and internal fertilization. It was originally identified as a major product of testicular Leydig cells and has proved to be an important biomarker of Leydig cell functional capacity. However, INSL3 is also produced by theca interna cells of growing antral follicles and is secreted into the bloodstream in phases corresponding to the number and health of the follicles. Moreover, gene silencing experiments have shown that INSL3 is essentially required for androstenedione synthesis, which is the major steroid precursor for the granulosa cells of antral follicles to produce oestrogens. Knockout studies in mice confirm that loss of INSL3 or its receptor in females leads to partial infertility, with reduced follicle numbers, ovulations and litter size. Circulating INSL3 concentration corresponds to the reproductive lifespan, beginning with puberty and declining at the menopause, and thus may contribute to the physiology of other organ systems, particularly those relevant for hormone replacement strategies. A literature review was carried out by exhaustive searching of literature databases (PubMed and Google Scholar) with the search terms INSL3, RLF, Ley-IL and RXFP2. We present the first comprehensive review of INSL3 and its specific receptor RXFP2, and their roles in the context of female reproductive physiology. Moreover, we highlight the potential involvement of INSL3 in female reproductive pathology, such as PCOS, its clinical application as a valuable biomarker of reproductive processes, and its potential for therapeutic interventions. In the female mammal, INSL3 is largely produced by the theca interna cells of growing antral follicles during the follicular phase of the menstrual (oestrous) cycle. Within the follicle, INSL3 acts via its G-protein-coupled receptor, RXFP2, in an autocrine/paracrine manner to orchestrate and drive the production of the major steroid precursor androstenedione and its conversion by granulosa cells into oestrogens. These in turn create a positive feedback loop promoting the expression of more theca cell INSL3. This is countered by the follicular production of bone morphogenetic proteins and by the LH surge. Thus, the activity of the theca cell INSL3-RXFP2 system effectively determines the production of estradiol within an antral follicle through the follicular phase. INSL3 is also secreted into the circulation where it acts as a valuable biomarker to monitor the growth of antral follicles; it is consequently increased in PCOS and decreased in women with premature ovarian failure (POF). As an endocrine factor, INSL3 may also influence bone metabolism and kidney function. Additionally, INSL3 or its analogues may prove valuable as an adjunct in hormone replacement therapy or to monitor or influence IVF protocols. The INSL3-RXFP2 system represents a new regulatory pathway essential for the proper functioning of growing antral follicles. We still know very little about its involvement in pathologies such as PCOS or POF, and its role as a new biomarker of female function needs to be explored more widely to improve diagnosis and treatment of ovarian dysfunction. We need to examine how INSL3 might be used to improve IVF protocols and outcomes. Opportunities should also be investigated in regard to the systemic application of INSL3 as a rejuvenant therapy, with positive effects on bone or kidney function, and possibly also for fertility regulation. Most research to date has involved animal models; this now needs to be extended to include more human studies.

Identification of 9-oxo-1,2,3,4,5,6,10,19-octanor-13,17-secoandrost-8(14)-ene-7,17-dioic acid as a metabolite of steroid degradation in Comamonas testosteroni TA441 and the genes involved in the conversion

Comamonas testosteroni TA441 degrades steroid compounds via aromatization of the A-ring to produce 9,17-dioxo-1,2,3,4,10,19-hexanorandrostan-5-oic acid (a metabolite with C- and D-rings), which is presumed to be further degraded via β-oxidation. In elucidating the complete steroid degradation process in C. testosteroni, we isolated 9-oxo-1,2,3,4,5,6,10,19-octanor-13,17-secoandrost-8(14)-ene-7,17-dioic acid and several other metabolites containing only C-ring. For conversion of the CoA-ester of this compound, a two-subunit β -ketoacyl-CoA-transferase encoded by ORF1 and ORF2 was shown to be indispensable. ORF1 and ORF2 are located just after tesB, the meta-cleavage enzyme gene in one of the two major steroid degradation gene clusters of strain TA441. Conversion by the CoA-transferase leads to cleavage of the remaining C-ring, and the product was suggested to be further degraded by β-oxidation involving other genes in the cluster. ORF1 and ORF2 are considered orthologues of ipdAB gene in Mycobacterium tuberculosis H37Rv, which is recently reported as the CoA-transferase of 9-oxo-1,2,3,4,5,6,10,19-octanor-13,17-secoandrost-8(14)-ene-7,17-dioic acid (Crowe AM, Casabon I, Brown KL, Liu J, Lian J, Rogalski JC, Hurst TE, Snieckus V, Foster LJ, Eltis LD. 2017. MBio 8).

The protective effect of estrogen on cisplatin‐induced cytotoxicity of HK‐2 cells

Introduction and hypothesisCisplatin is a widely used chemotherapeutic agent and has significant renal toxicity. Estrogen is a major sex hormone in females, and previous studies have shown that estrogen has many physiological protective effects. HK‐2 cell line is an immortalized proximal tubule epithelial cell line from healthy men. In this study, we investigated the protective roles of estrogen on cisplatin‐induced nephrotoxicity by the in vitro HK‐2 cell model.MethodsHK‐2 Cells were pretreated with 17β‐estradiol (0~20 nM), estrogen receptor agonists, and estrogen receptor antagonists for 24 hours respectively. All groups of cells were followed treated with cisplatin (0–15 mg/ml) for 24 hours. The cell survival rate, proliferation, morphology were analyzed by ELISA. The apoptosis/necrosis were analyzed by Annexin‐V/PI staining using flow cytometry. Estrogen receptors and apoptosis related proteins expressions were confirmed by Western blotting.ResultsAll three types of estrogen receptors could be expressed by the HK‐2 cells. In cisplatin‐induced nephrotoxicity cell model, 17β‐estradiol pretreatment have higher cell survival rate than vehicle when dose larger than 10 nM. The Annexin‐V positive apoptotic cells and caspase‐3 expressions in 17β‐estradiol pretreated group is significant lower than vehicle control. The three types of estrogen agonists exert the protective effects in cisplatin‐induced cytotoxicity, and acted on the G protein‐coupled estrogen receptor (GPER) is the most effective. In addition, blocked GPER also significantly accentuated cytotoxicity of cisplatin treated HK‐2 cells.ConclusionsOur data suggested that estrogen pretreatment could protect HK‐2 cells from cisplatin induced cytotoxicity, and this protective effect occurs mainly through the GPER pathway. It may offer a novel therapeutic strategy for cisplatin‐induced nephrotoxicity. Further investigation into the molecular mechanisms and clinical applications are needed.Support or Funding InformationKMU‐TP105E37This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Testosterone in the Bedroom ‐ Not All Good

There are no effective therapeutics to prevent the progression of neurodegenerative diseases, such as Alzheimer's disease (AD) or Parkinson's disease (PD). This deficit highlights the need to identify early contributors to neurodegenerative pathophysiology, such as examining common comorbidities. One such comorbidity is sleep apnea. To examine the relationship between sleep apnea and neurodegeneration, we used a rodent model of chronic intermittent hypoxia (CIH) to simulate the hypoxic events experienced by patients with sleep apnea. Interestingly, in male rats CIH causes an increase in oxidative stress and inflammation, along with a decrease in circulating testosterone (T). These findings are consistent with key characteristics of neurodegeneration. Since sex differences can be observed in both sleep apnea and neurodegeneration, it has been hypothesized sex hormones may underlie this sex difference. Currently, studies have been equivocal about the role of the major male sex hormone, T, in neuroprotection and neurodegeneration. It has been proposed that an oxidative stress environment may predispose T to be neurotoxic via androgen receptor activation. To address if oxidative stress is the switch for testosterone's neuroprotective or neurotoxic actions, we used male Long‐Evans rats assigned to different hormone treatment groups: gonadally intact, gonadectomized (GDX – hormone deficient), gonadectomized + T, gonadally intact + T, or gonadectomized + dihydotestosterone (DHT). Two weeks after hormone replacement, rats were exposed to CIH (used as an oxidative stressor) or room air (AHI = 8) for 12 days. During the last 5 days of CIH, cognitive and motor behavioral assessments were conducted. As expected, we observed increased oxidative stress and spatial memory impairments in response to CIH in gonadally intact rats, which is consistent with patients with sleep apnea. In addition to memory impairments, gonadally intact male rats exposed to CIH exhibited fine motor impairments. Although fine motor skills have not been assessed in clinical sleep apnea populations, delayed motor reaction times have been reported. This suggests CIH‐induced oxidative stress results in behavioral deficits associated with early‐stages of neurodegenerative diseases. Since CIH decreases T, we examined the effects of CIH on hormone deficient rats (GDX) and exogenous hormone replacement rats (GDX + T & intact + T). GDX rats exhibited only cognitive impairments, regardless of CIH exposure, indicating sex hormones play a role in memory. Irrespective of CIH exposure, maintaining physiological levels of T prevented oxidative stress generation as well as motor and cognitive impairments. Since T can activate both estrogen and androgen receptors, we wanted to isolate the effects of androgen receptor activation. Therefore, we used DHT, a T metabolite and an androgen receptor specific agonist. CIH induced oxidative stress and cognitive impairments were exacerbated in GDX + DHT male rats, compared to gonadally intact rats. These results indicate that the androgen receptor is involved in T's negative effects in an oxidative stress environment. Since sleep apnea is a common comorbidity of neurodegeneration, the observed sex differences may be due to a negative interaction between oxidative stress and androgen receptor activation. Therefore, men with sleep apnea who have elevated oxidative stress may be susceptible to neurodegenerative pathophysiology.Support or Funding InformationNational Institutes of Health (NIH) R01 NS088514 to RLCNIH training grant T32 AG 020494 to BDSThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Atorvastatin decreases steroid production in H295R cells and in major endocrine tissues of male rats.

Obesity is increasing worldwide, and since obesity is associated with dyslipidemia, the consumption of cholesterol-lowering pharmaceuticals has increased. The aim of this study was therefore to study potential endocrine disrupting effects of one of the world's most frequently prescribed drugs, the cholesterol-lowering drug, atorvastatin (ATO) in vitro using the H295R steroidogenesis assay and in vivo using male Sprague-Dawley rats. We analyzed all major steroids in the mammalian steroidogenesis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). In vitro, ATO significantly decreased all steroids in the H295R steroidogenesis at concentrations close to human plasma Cmax values, with an IC50 value for testosterone of 0.093 ± 0.033µM. Additionally, we determined steroid hormone levels in testis, adrenals, brain and plasma from rats after 14days of exposure to three therapeutically relevant doses of ATO and observed pronounced decreasing steroid levels in particular in testis and adrenals but also in brain and plasma. In testis, all major steroidogenic enzymes were up-regulated, indicating autocrine and/or paracrine compensation for the decrease in steroid production by this tissue. In adrenals, StAR and CYP11A1 gene expression were decreased, whereas little effects were observed in the brain. Furthermore, we analyzed plasma LH and ACTH levels to investigate feedback via the PT and HPA axes. No effects were observed on LH levels, indicating little compensation via the PT axis. In contrast, ACTH levels increased during ATO exposure, indicating that the HPA axis to some extend compensated for the decrease in adrenal steroid production. Overall, ATO exerted pronounced effects on steroid production both in vitro and in vivo at therapeutically relevant doses. This clearly demonstrates the high potency of ATO to affect steroid homeostasis during therapeutic treatment. Further clinical and epidemiological studies should be conducted to investigate the relevance of these observations in patients treated with cholesterol-lowering pharmaceuticals.

Sertraline Suppresses Testis and Adrenal Steroid Production and Steroidogenic Gene Expression While Increasing LH in Plasma of Male Rats Resulting in Compensatory Hypogonadism.

Selective serotonin reuptake inhibitors are used as first line treatment in major depressive disorder. However, selective serotonin reuptake inhibitors have also been associated with sexual disorders, abnormalities, and sexual dysfunction, although mechanisms are unclear. The aim of this project was to investigate the possible endocrine disrupting effect of sertraline (SER) on sex steroid production in male rats exposed to 3 therapeutically realistic doses of SER 1.25, 5, and 20 mg/kg/day. To achieve this, we analyzed all the major steroids in testis, adrenals, brain, and plasma using Liquid chromatography tandem mass spectrometry. Furthermore, we investigated the potential effects on gene expression on the major genes involved in testicular, adrenal and brain steroidogenesis using quantitative PCR. Moreover, plasma luteinizing hormone (LH) levels were analyzed. We observed significant reduction in steroid production, in particular on the testicular Δ-4 axis and on the adrenal CYP17-hydroxylase axis. Effects in brain and plasma were less pronounced. Testicular gene transcription was also significantly down-regulated except for the CYP19 (aromatase) gene. In contrast, no effects on the adrenal gene expression were observed, except for an up-regulation of the CYP17. Plasma LH and LH/TS were increased, in particular in the lowest exposure group, indicating some degree of compensatory hypogonadism. In conclusion, this study demonstrates extensive endocrine disruption during SER exposure in male rats, both directly on steroid production in major endocrine tissues, but also indirectly by affecting gene expression. Furthermore, increased LH levels may augment decreased sex steroid production, in particular testosterone production, inducing a state of compensatory hypogonadism.

Estradiol level of male rat is correlated with depression and anxiety after traumatic stress

Post-traumatic stress disorder (PTSD) is a complex syndrome that is defined by individual exposed to intense, life-threatening trauma thereby leading to physical and psychological abnormalities. They further develop additional symptoms including persistent anxiety, exaggerated startle, cognitive impairments, and diminished extinction of fear. Most of the previous studies focused on brain and neurophysiology, but PTSD affects the whole body. Therefore, we wanted to concentrate more on the effects on sex hormones using rats. Testosterone and estradiol are major sex hormones in male and female which are well known to participate in not only reproduction but also brain function and behaviors. Two behavioral tests, open field test and tail suspension test, were used to determine whether animals have PTSD-like symptoms. At the same time, serum samples were collected for sex hormone analysis. We investigated the influences of traumatic stress and then tried to find out the correlations of behaviors and hormones. In results, 22% of rats were affected by stress based on the behavioral tests and grouped as PTSD-like. These rats showed enhanced anxiety and depression behaviors. In serum samples from the PTSD-like group, only estradiol levels in male after stress are significant higher than the control or stressed but no symptom groups. Testosterone level showed no difference after stress both in male and female. We also observed that only estradiol level in male correlates with PTSD-like behaviors. It indicates that estradiol levels in male just after traumatic stress might be an indicator for PTSD-like symptoms.

Comparative Evaluation of Salivary Cortisol Levels in Bruxism Patients Before and After Using Soft Occlusal Splint: An in vivo Study.

Introduction:Bruxism is defined as a nonfunctional activity or a parafunctional habit characterized by the unconscious repetitive motion of clenching and/or grinding of the teeth. Soft occlusal splints have been considered as the first-line strategy for treating nocturnal bruxism. Cortisol is a major steroid hormone secreted by fascicular zone of the adrenal cortex, belonging to the glucocorticosteroidal group of hormones. Clinical studies have shown that when humans are placed under stress, the hypothalamic–pituitary–adrenocortical axis is activated, leading to an increase in cortical secretion. However, the effect of splint is questionable by some researchers, and best way to perceive the effect of soft splints in patients with bruxism is by evaluating the stress levels.Materials and Methods:A total of 20 individuals suffering from bruxism were selected from the Outpatient Department of Prosthodontics and Crown and Bridge, JSS Dental College and Hospital, Mysore. Saliva samples were collected before and after using the occlusal soft splints and subjected to enzyme-linked immunosorbent assay for determining the salivary cortisol levels.Results:The collected data were subjected to appropriate descriptive statistics, paired sample t-test, and one sample t-test. The paired sample t-test shows that intragroup comparison of the mean cortisol level in the study group shows near significant values, which means there is a decrease in the salivary cortisol levels in patients after using soft occlusal splint, but statistically nonsignificant.Conclusion:In the present study, it has been found that 70% of individuals after using the soft occlusal splint showed decreased cortisol levels.

Effect of puberty on multiple sclerosis risk and course

Puberty occurs over several years and is a time of major sex hormone changes. These changes impact many physiological functions including immune system maturation. This review details the current understanding of the impact of puberty on the risk to develop multiple sclerosis (MS) and the age at which it occurs, as well as its effect on the risk of relapses.

Theca Cell INSL3 and Steroids Together Orchestrate the Growing Bovine Antral Follicle.

Insulin-like peptide 3 (INSL3) and its specific receptor RXFP2 are both expressed by theca interna cells of the growing antral follicle where they form an essential regulatory element in the production of the steroid precursor androstenedione. Using primary cultures of bovine theca cells from the mid follicular phase together with steroid agonists and antagonists we have examined how ovarian steroids modulate INSL3 expression. Transcript analysis shows that these cells express estrogen receptors α and β, androgen and progesterone receptors, besides the orphan nuclear receptors SF1 and nur77. Whereas, exogenous androgens have little or no effect, the androgen antagonist bicalutamide stimulates INSL3 production. In contrast, estrogen receptor agonists, as also progesterone, are stimulatory. Importantly, estrogen receptor signaling is convergent with the protein kinase A signaling pathway activated by LH, such that the estrogen receptor antagonist can inhibit the mild stimulatory effect of LH, and vice versa the PKA antagonist H89 blocks stimulation by estradiol. A significant finding is that the major steroid metabolite androstenedione appears to act predominantly as an estrogen and not an androgen in this system. Transfection of INSL3 gene promoter-reporter constructs together with various steroid receptor expression plasmids supports these findings and shows that steroid action uses non-classical pathways not requiring canonical steroid-responsive elements in the proximal promoter region. Together, the results indicate that increasing estrogens in the follicular phase stimulate a feedforward loop driving INSL3 signaling and thereby promoting steroidogenesis in the growing antral follicle until the LH surge which effectively switches off INSL3 expression.

Genome-wide analysis of health-related biomarkers in the UK Household Longitudinal Study reveals novel associations

Serum biomarker levels are associated with the risk of complex diseases. Here, we aimed to gain insights into the genetic architecture of biomarker traits which can reflect health status. We performed genome-wide association analyses for twenty serum biomarkers involved in organ function and reproductive health. 9,961 individuals from the UK Household Longitudinal Study were genotyped using the Illumina HumanCoreExome array and variants imputed to the 1000 Genomes Project and UK10K haplotypes. We establish a polygenic heritability for all biomarkers, confirm associations of fifty-four established loci, and identify five novel, replicating associations at genome-wide significance. A low-frequency variant, rs28929474, (beta = 0.04, P = 2 × 10−10) was associated with levels of alanine transaminase, an indicator of liver damage. The variant is located in the gene encoding serine protease inhibitor, low levels of which are associated with alpha-1 antitrypsin deficiency which leads to liver disease. We identified novel associations (rs78900934, beta = 0.05, P = 6 × 10−12; rs2911280, beta = 0.09, P = 6 × 10−10) for dihydroepiandrosterone sulphate, a precursor to major sex-hormones, and for glycated haemoglobin (rs12819124, beta = −0.03, P = 4 × 10−9; rs761772, beta = 0.05, P = 5 × 10−9). rs12819124 is nominally associated with risk of type 2 diabetes. Our study offers insights into the genetic architecture of well-known and less well-studied biomarkers.