The molecular biology, biochemistry, and physiology of human steroidogenesis and its disorders

Systemic proteome phenotypes reveal defective metabolic flexibility in Mecp2 mutants

Genes mutated in monogenic neurodevelopmental disorders are broadly expressed. This observation supports the concept that monogenic neurodevelopmental disorders are systemic diseases that profoundly impact neurodevelopment. We tested the systemic disease model focusing on Rett syndrome, which is caused by mutations in MECP2. Transcriptomes and proteomes of organs and brain regions from Mecp2-null mice as well as diverse MECP2-null male and female human cells were assessed. Widespread changes in the steady-state transcriptome and proteome were identified in brain regions and organs of presymptomatic Mecp2-null male mice as well as mutant human cell lines. The extent of these transcriptome and proteome modifications was similar in cortex, liver, kidney, and skeletal muscle and more pronounced than in the hippocampus and striatum. In particular, Mecp2- and MECP2-sensitive proteomes were enriched in synaptic and metabolic annotated gene products, the latter encompassing lipid metabolism and mitochondrial pathways. MECP2 mutations altered pyruvate-dependent mitochondrial respiration while maintaining the capacity to use glutamine as a mitochondrial carbon source. We conclude that mutations in Mecp2/MECP2 perturb lipid and mitochondrial metabolism systemically limiting cellular flexibility to utilize mitochondrial fuels.

Structural and clinical characterization of CYP11B2 inhibition by dexfadrostat phosphate

Aldosterone synthase (CYP11B2) represents a promising drug target because its genetic dysregulation is causally associated with cardiovascular disease, its autonomous activity leads to primary aldosteronism, and its deficiency leads to salt wasting syndromes. The serendipitous discovery that the dextro-rotatory stereoisomer of the racemic aromatase (CYP19A1) inhibitor CGS16949A mediates potent CYP11B2 inhibition led to the purification and clinical development of dexfadrostat phosphate. To characterize the pharmacophore of dexfadrostat phosphate, structure-based enzyme coordination with CYP11B2, CYP11B1 and CYP19A1 was combined with steroid turnover upon in vitro and clinical treatment. Dexfadrostat, but not its 5S-enantiomer (5S-fadrozole), precisely coordinates with the catalytic heme moiety in the space of the CYP11B2 substrate binding pocket forming a tight and stable complex. Conversely, neither rigid nor flexible docking led to a plausible coordination geometry for dexfadrostat in steroid 11β-hydroxylase (CYP11B1 - orthologue to CYP11B2) or in CYP19A1. The inhibitory preference of dexfadrostat was confirmed in vitro using an adrenal cortex-derived cell line. Dexfadrostat phosphate treatment of healthy subjects in the context of a clinical phase 1 study led to a dose-dependent decrease in urinary aldosterone secretion, accompanied by an increase in urinary corticosterone and deoxycorticosterone metabolites. Increased urinary corticosterone metabolites are indicative of CYP11B2 (18-oxidase) inhibition with clinical features reminiscent of patients with inborn corticosterone methyloxidase type II deficiency. An off-target effect on CYP19A1 was not observed as indicated by no clinical changes in testosterone and estradiol levels. Therefore, dexfadrostat exhibits the ideal structural features for binding and catalytic inhibition of CYP11B2 but not CYP11B1. Clinically, treatment with dexfadrostat phosphate leads to suppression of aldosterone levels by inhibiting predominantly one or both final CYP11B2-mediated reactions.

Downregulation of the Expression of Steroidogenic Acute Regulatory Protein and Aromatase in Steroidogenic KGN Human Granulosa Cells after Exposure to Bisphenol A

Although increasing evidence of cause-and-effect relationship between BPA exposure and female reproductive disorders have been suggested through many studies, the precise biochemical and molecular mechanism(s) by which BPA interferes with steroidogenesis in the ovarian cells still remain unclear. Therefore, the purpose of this study was to discover the steroidogenic biomarker(s) associated with BPA treatment in human granulosa cell line, KGN. In this study, our results obtained via the analysis of steroidogenesis-related protein expression in KGN cells using quantitative polymerase chain reaction (qPCR) and western blot analyses revealed that the expression levels of steroidogenic acute regulatory (StAR) and aromatase decreased considerably and gradually after BPA treatment in a dose-dependent manner under BPA treatment. Further, remarkable decreases in their expression levels at the cellular levels were also confirmed via immunocytochemistry, and subsequent StAR and aromatase mRNA expression levels showed profiles similar to those observed for their proteins, i.e., both StAR and aromatase mRNA expression levels were significantly decreased under BPA treatment at concentrations ≥0.1 μM. We observed that follicle stimulating hormone upregulated StAR and aromatase protein expression levels; however, this effect was suppressed in the presence of BPA. Regarding the steroidogenic effects of BPA on KGN cells, controversies remain regarding the ultimate outcomes. Nevertheless, we believe that the results here presented imply that KGN cells have a good cellular and steroidogenic machinery for evaluating endocrine disruption. Therefore, StAR and aromatase could be stable and sensitive biomarkers in KGN cells for the cellular screening of the potential risk posed by exogenous and environmental chemicals to female reproductive (endocrine) function.

Expression of cholesterol synthesis and steroidogenic markers in females of the Chinese brown frog (Rana dybowskii) during prespawning and prehibernation

The oviduct of the Chinese brown frog (Rana dybowskii) expands in prehibernation rather than in prespawning, which is one of the physiological phenomena that occur in the preparation for hibernation. Steroid hormones are known to regulate oviductal development. Cholesterol synthesis and steroidogenesis may play an important role in the expansion of the oviduct before hibernation. In this study, we investigated the expression patterns of the markers that are involved in the de novo steroid synthesis pathway in the oviduct of R. dybowskii during prespawning and prehibernation. According to histological analysis, the oviduct of R. dybowskii contains epithelial cells, glandular cells, and tubule lumens. During prehibernation, oviductal pipe diameter and weight were significantly larger than during prespawning. 3-Hydroxy-3-methylglutaryl CoA reductase (HMGCR), low-density lipoprotein receptor (LDLR), steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and steroidogenic factor 1 (SF-1) were detected in epithelial cells in prehibernation and glandular cells during prespawning. HMGCR, LDLR, StAR, and P450scc protein expression levels were higher in prehibernation than during prespawning, but the SF-1 protein expression level did not significantly differ. HMGCR, LDLR, StAR, P450scc (CYP11A1), and SF-1 (NR5A1) mRNA expression levels were significantly higher in prehibernation compared with prespawning. The transcriptome results showed that the steroid synthesis pathway was highly expressed during prehibernation. Existing results indicate that the oviduct is able to synthesize steroid hormones using cholesterol, and that steroid hormones may affect the oviductal functions of R. dybowskii.

Dietary exposure to an environmentally relevant phthalate mixture alters follicle dynamics, hormone levels, ovarian gene expression, and pituitary gene expression in female mice

Phthalates are chemicals ubiquitously used in industry. Individual phthalates have been found to adversely affect female reproduction; however, humans are exposed to a mixture of phthalates daily, primarily through ingestion. Previous studies show that exposure to an environmentally relevant mixture of phthalates (Mix) can affect female reproduction. Little research, however, has been conducted on the effects of short-term (1 month) and long-term (6 months) exposure to Mix on ovarian functions. Thus, this study tested the hypothesis that short-term and long-term exposure to Mix alters ovarian folliculogenesis, serum hormone concentrations, pituitary gene expression, and ovarian expression of genes involved in steroidogenesis, apoptosis, cell cycle regulation, and oxidative stress. Adult CD-1 female mice were exposed to vehicle control (corn oil) or Mix (0.15-1500 ppm) in the chow for 1 or 6 months. Exposure to Mix for 1 month increased the number of atretic follicles (0.15 ppm), altered ovarian gene expression (0.15 ppm, 1500 ppm), and decreased serum testosterone (1.5 ppm) compared to control. Exposure to Mix for 6 months increased serum follicle-stimulating hormone (FSH) (0.15 ppm), decreased serum luteinizing hormone (LH) (0.15 ppm, 1.5 ppm, and 1500 ppm), decreased serum estradiol (1500 ppm), altered pituitary gene expression (1500 ppm), increased the number (1500 ppm) and percentage (1.5 ppm and 1500 ppm) of primordial follicles, and decreased the percentage of preantral (1500 ppm) and antral (1.5 ppm and 1500 ppm) follicles compared to control. These data indicate that exposure to Mix can alter folliculogenesis, steroidogenesis, and gene expression in female mice.

Dietary rumen-protected L-arginine or N-carbamylglutamate enhances placental amino acid transport and suppresses angiogenesis and steroid anabolism in underfed pregnant ewes

This study aimed to investigate the effects of dietary supplementation of underfed Hu ewes from d 35 to 110 of gestation with either rumen-protected L-arginine (RP-Arg) or N-carbamylglutamate (NCG) on placental amino acid (AA) transport, angiogenic gene expression, and steroid anabolism. On d 35 of gestation, 32 Hu ewes carrying twin fetuses were randomly divided into four treatment groups, each consisting of eight ewes, and were fed the following diets: A diet providing 100% of NRC's nutrient requirements for pregnant ewes (CON); A diet providing 50% of NRC's nutrient requirements for pregnant ewes (RES); RES diet plus 5 g/d NCG (RES + NCG); or RES diet plus 20 g/d RP-Arg (RES + ARG). On the d 110 of pregnancy, blood samples were taken from the mother, and samples were collected from type A cotyledons (COT; the fetal portions of the placenta). The levels of 17β-estradiol and progesterone in the maternal serum and both the capillary area density (CAD) and capillary surface density (CSD) in type A COT were decreased in response to Arg or NCG supplementation when compared to the RES group. The concentrations of arginine, leucine, putrescine and spermidine in type A COT were higher (P < 0.05) in the RES + ARG or RES + NCG group than in the RES group. The mRNA expression levels of inducible nitric oxide synthase (iNOS) and solute carrier family 15, member 1 (SLC15A1) were increased (P < 0.05) while those of progesterone receptor (PGR) and fibroblast growth factor 2 (FGF2) were decreased in type A COT by supplementation with either NCG or RP-Arg compared to the RES group. The results suggest that providing underfed pregnant ewes from d 35 to 110 of gestation with a diet supplemented with NCG or RP-Arg improves placental AA transport, and reduces the expression of angiogenic growth factor genes and steroid anabolism, leading to better fetal development.

MicroRNA regulation of adrenal glucocorticoid and androgen biosynthesis

Steroid hormones are derived from a common precursor molecule, cholesterol, and regulate a wide range of physiologic function including reproduction, salt balance, maintenance of secondary sexual characteristics, response to stress, neuronal function, and various metabolic processes. Among the steroids synthesized by the adrenal and gonadal tissues, adrenal mineralocorticoids, and glucocorticoids are essential for life. The process of steroidogenesis is regulated at multiple levels largely by transcriptional, posttranscriptional, translational, and posttranslational regulation of the steroidogenic enzymes (i.e., cytochrome P450s and hydroxysteroid dehydrogenases), cellular compartmentalization of the steroidogenic enzymes, and cholesterol processing and transport proteins. In recent years, small noncoding RNAs, termed microRNAs (miRNAs) have been recognized as major post-transcriptional regulators of gene expression with essential roles in numerous biological processes and disease pathologies. Although their role in the regulation of steroidogenesis is still emerging, several recent studies have contributed significantly to our understanding of the role miRNAs play in the regulation of the steroidogenic process. This chapter focuses on the recent developments in miRNA regulation of adrenal glucocorticoid and androgen production in humans and rodents.

Comparison of Steroidogenic and Ovulation-Inducing Effects of Orthosteric and Allosteric Agonists of Luteinizing Hormone/Chorionic Gonadotropin Receptor in Immature Female Rats

Gonadotropins, including human chorionic gonadotropin (hCG), are used to induce ovulation, but they have a number of side effects, including ovarian hyperstimulation syndrome (OHSS). A possible alternative is allosteric luteinizing hormone (LH)/hCG receptor agonists, including the compound TP4/2 we developed, which remains active when administered orally. The aim was to study the effectiveness of TP4/2 (orally, 40 mg/kg) as an ovulation inducer in FSH-stimulated immature female rats, compared with hCG (s.c., 15 IU/rat). TP4/2 stimulated progesterone production and corpus luteum formation; time-dependently increased the ovarian expression of steroidogenic genes (Star, Cyp11a1, Cyp17a1) and genes involved in ovulation regulation (Adamts-1, Cox-2, Egr-1, Mt-1); and increased the content of metalloproteinase ADAMTS-1 in the ovaries. These effects were similar to those of hCG, although in some cases they were less pronounced. TP4/2, in contrast to hCG, maintained normal LH levels and increased the ovarian expression of the LH/hCG receptor gene, indicating preservation of ovarian sensitivity to LH, and did not cause a sustained increase in expression of vascular endothelial growth factor-A involved in OHSS. Thus, TP4/2 is an effective ovulation inducer that, unlike hCG, has a lower risk of OHSS and ovarian LH resistance due to its moderate stimulating effect on steroidogenesis.

Cardiac glycosides protect wormseed wallflower (Erysimum cheiranthoides) against some, but not all, glucosinolate-adapted herbivores

The chemical arms race between plants and insects is foundational to the generation and maintenance of biological diversity. We asked how the evolution of a novel defensive compound in an already well-defended plant lineage impacts interactions with diverse herbivores. Erysimum cheiranthoides (Brassicaceae), which produces both ancestral glucosinolates and novel cardiac glycosides, served as a model.We analyzed gene expression to identify cardiac glycoside biosynthetic enzymes in E. cheiranthoides and characterized these enzymes via heterologous expression and CRISPR/Cas9 knockout. Using E. cheiranthoides cardiac glycoside-deficient lines, we conducted insect experiments in both the laboratory and field.EcCYP87A126 initiates cardiac glycoside biosynthesis via sterol side chain cleavage, and EcCYP716A418 has a role in cardiac glycoside hydroxylation. In EcCYP87A126 knockout lines, cardiac glycoside production was eliminated. Laboratory experiments with these lines revealed that cardiac glycosides were highly effective defenses against two species of glucosinolate-tolerant specialist herbivores but did not protect against all crucifer-feeding specialist herbivores in the field. Cardiac glycosides had lesser to no effect on two broad generalist herbivores.These results begin elucidation of the E. cheiranthoides cardiac glycoside biosynthetic pathway and demonstrate in vivo that cardiac glycoside production allows Erysimum to escape from some, but not all, specialist herbivores.

Maternal hypercholesterolemia would increase the incidence of embryo aneuploidy in couples with recurrent implantation failure

BACKGROUND

The association of dyslipidemia with embryo development and pregnancy outcomes is largely unknown, especially in unexplained recurrent implantation failure (uRIF) patients. Here, this study aimed to explore the impact of abnormal blood lipid levels on embryo genetic status and pregnancy outcomes after preimplantation genetic testing for aneuploidy (PGT-A) from a clinical perspective.

METHODS

This study retrospectively analyzed 502 patients diagnosed as uRIF. They were divided into four groups according to the levels of cholesterol and triglyceride: nonhyperlipidemia group (NonH group), simple hypercholesterolemia group (SHC group), simple hypertriglyceridemia group (SHC group) and mixed hyperlipidemia group (MixH group). At the same time, patients were divided into non-low HDL-C group and low HDL-C group according to their HDL-C level. The outcomes of embryos genetic testing and pregnancy outcomes after PGT-A was analyzed between groups. Binary logistic regression and/or generalized estimating equation (GEE) model were conducted to investigate the association of different types of dyslipidemia with embryonic aneuploidy rate and cumulative live-birth rate.

RESULTS

474 women who met the inclusion criteria were divided into four groups: NonH group (N = 349), SHC group (N = 55), SHT group (N = 52) and MixH group (N = 18). Compared with the NonH group, SHC group had a significantly increased rate of embryo aneuploidy [48.3% vs. 36.7%, P = 0.006; adjusted OR (95% confidence interval) = 1.52(1.04-2.22), P = 0.029], as well as a reduced number of good-quality embryos on day 5 or 6 [3.00 ± 2.29 vs. 3.74 ± 2.77, P = 0.033]. The SHC group showed a tendency of a lower cumulative live birth rate (47.0% vs. 40.0%), a lower incidence of good birth outcome (37.2% vs. 34.5%) and a higher risk of clinical pregnancy loss (11.1% vs. 17.9%), but did not reach statistical significance (P > 0.05). The incidences of obstetric or neonatal complications and other adverse events were similar in the four groups. Whether patients have low HDL-C did not differ in pregnancy outcomes.

CONCLUSIONS

We found that uRIF women with hypercholesterolemia had an increased proportion of aneuploid embryos and a reduced proportion of high-quality embryos, while different types of hyperlipidemia had no correlation with cumulative live birth rate as well as pregnancy and neonatal outcomes.

Hypoxia activation attenuates progesterone synthesis in goat trophoblast cells via NR1D1 inhibition of StAR expression†

Trophoblast plays a crucial role in gestation maintenance and embryo implantation, partly due to the synthesis of progesterone. It has been demonstrated that hypoxia regulates invasion, proliferation, and differentiation of trophoblast cells. Additionally, human trophoblasts display rhythmic expression of circadian clock genes. However, it remains unclear if the circadian clock system is present in goat trophoblast cells (GTCs), and its involvement in hypoxia regulation of steroid hormone synthesis remains elusive. In this study, immunofluorescence staining revealed that both BMAL1 and NR1D1 (two circadian clock components) were highly expressed in GTCs. Quantitative real-time PCR analysis showed that several circadian clock genes were rhythmically expressed in forskolin-synchronized GTCs. To mimic hypoxia, GTCs were treated with hypoxia-inducing reagents (CoCl2 or DMOG). Quantitative real-time PCR results demonstrated that hypoxia perturbed the mRNA expression of circadian clock genes and StAR. Notably, the increased expression of NR1D1 and the reduction of StAR expression in hypoxic GTCs were also detected by western blotting. In addition, progesterone secretion exhibited a notable decline in hypoxic GTCs. SR9009, an NR1D1 agonist, significantly decreased StAR expression at both the mRNA and protein levels and markedly inhibited progesterone secretion in GTCs. Moreover, SR8278, an NR1D1 antagonist, partially reversed the inhibitory effect of CoCl2 on mRNA and protein expression levels of StAR and progesterone synthesis in GTCs. Our results demonstrate that hypoxia reduces StAR expression via the activation of NR1D1 signaling in GTCs, thus inhibiting progesterone synthesis. These findings provide new insights into the NR1D1 regulation of progesterone synthesis in GTCs under hypoxic conditions.

Determination of well-being-related markers in nails by liquid chromatography tandem mass spectrometry

Well-being is a multifactorial positive state that is highly influenced by some endogenous molecules that control happiness and euphoric feelings. These molecules, e.g., neurotransmitters, hormones and their derivatives, play a crucial role in metabolism and may be referred to as "well-being-related markers". The deregulation of well-being-related markers can lead to organism malfunctions and life-threatening states. In this research, we aimed to evaluate the potential of nails for the chronic production of several well-being-related markers. For this purpose, we developed an LCMS /MS-based method for the determination of 10 well-being-related markers, including melatonin, serotonin, cortisol, kynurenine and several precursors and metabolites. The method was optimized regarding different analytical steps: required sample amount, extraction time, number of required extractions, preconcentration, injection volume and MS conditions. Method validation was performed by two different approaches: (i) using surrogate nail matrix and (ii) using authentic nail samples by standard additions. The method was found to be linear in the expected endogenous range and sensitive enough to determine the low endogenous concentration levels in nails. Accuracy and precision were appropriate in both validation approaches. As proof of concept, the method was used (i) to correlate fingernail and toenail levels for all metabolites in 22 volunteers, (ii) to establish the endogenous concentration range of all metabolites in females (n = 50) and males (n = 34) and (iii) to correlate the metabolite levels with age. For some metabolites, the calculated ranges have been reported for the first time. In summary, the present strategy to evaluate well-being-related markers in nails may be a useful tool for the evaluation of the production of these important compounds with high potential for a wide range of clinical purposes.

Minipuberty in Sons of Women with Low Vitamin D Status during Pregnancy

Minipuberty is a transient phase of reproductive axis activation during the first several months of life, playing an important role in the development of reproductive organs in boys. Low 25-hydroxyvitamin D levels during pregnancy are associated with an increased risk of neonatal complications. An inadequate gestational vitamin D status is hypothesized to affect the postnatal activation of the hypothalamic-pituitary-gonadal axis. The purpose of our study was to assess whether a low vitamin D status during pregnancy determines the course of minipuberty in boys. The study included three groups of male infants born to women with different vitamin D statuses: sons of women with vitamin D deficiency (group 1), sons of women with vitamin D insufficiency (group 2), and male offspring of females with normal 25-hydroxyvitamin D levels (group 3 (the reference group)). Concentrations of testosterone, androstenedione, dehydroepiandrosterone sulfate, estradiol, progesterone, and 17-hydroxyprogesterone in saliva, as well as concentrations of gonadotropins in urine, were assayed monthly from postnatal months 1 to 6, and once every 2 months in the second half of the first year of life. Additionally, at each visit, penile length and testicular volume were assessed. Concentrations of testosterone, FSH, and LH, as well as penile length and testicular volume, were greater in group 1 than in groups 2 and 3. In turn, group 2 was characterized by higher FSH levels and a greater testicular volume than group 3. Peak concentrations of LH and testosterone were observed earlier in group 1 than in the remaining groups. The obtained results suggest that a low vitamin D status during pregnancy may have a stimulatory impact on reproductive axis activity and on the early postnatal development of male genital organs, correlating with the severity of hypovitaminosis D.

Acyl-CoA synthase ACSL4: an essential target in ferroptosis and fatty acid metabolism

ABSTRACT

Long-chain acyl-coenzyme A (CoA) synthase 4 (ACSL4) is an enzyme that esterifies CoA into specific polyunsaturated fatty acids, such as arachidonic acid and adrenic acid. Based on accumulated evidence, the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation. Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids; ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis, respectively. In addition, ACSL4 is an essential regulator of fatty acid (FA) metabolism. ACSL4 remodels the phospholipid composition of cell membranes, regulates steroidogenesis, and balances eicosanoid biosynthesis. In addition, ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology. Because it facilitates the cross-talk between ferroptosis and FA metabolism, ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries. In this review, we focus on the structure, biological function, and unique role of ASCL4 in various human diseases. Finally, we propose that ACSL4 might be a potential therapeutic target.

Unexpectedly high mutation rate of cyp11b1 compared to cyp21a2 in randomly-selected turkish women: a large screening study

PURPOSE

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders resulting from enzyme deficiencies associated with steroidogenesis. The clinical presentation of non-classic CAH (NCAH) in females is often indistinguishable from other hyperandrogenic disorders like polycystic ovary syndrome (PCOS). The data on the prevalence of NCAH in unselected women in the literature is scanty. The research aimed to evaluate the prevalence of NCAH, carrier frequencies, and the correlation between clinical symptoms and genotype in Turkish women.

METHODS

The study group comprised two hundred and seventy randomly-selected unrelated asymptomatic women of reproductive age (18-45). Subjects were recruited from female blood donors. All volunteers underwent clinical examination and hormone measurements. The protein-encoding exons and exon-intron boundaries of the CYP21A2, CYP11B1, HSD3β2 and CYP21A2 promoter were sequenced by direct DNA sequencing.

RESULTS

After genotyping, seven (2.2%) individuals were diagnosed with NCAH. The heterozygous carrier frequencies of CYP21A2, CYP21A2 promoter, CYP11B1, and HSD3β2 genes with 34, 34, 41, and 1 pathologic mutation were determined at 12.6%, 12.6%, 15.2%, and 0.37% of volunteers, respectively. Gene-conversion (GC) frequencies between CYP21A2/CYP21A1P and CYP11B1/CYP11B2 were determined as 10.4% and 14.8%, respectively.

CONCLUSION

Despite GC-derived higher mutation frequency determined in the CYP11B1 gene, the reason for the low frequency of NCAH due to 11OHD compared to 21OHD might be that gene-conversion arises with active CYP11B2 rather than an inactive pseudogene. HSD3β1 exhibits high homology with HSD3β2 located on the same chromosome; remarkably, it demonstrates low heterozygosity and no GC, most probably the outcome of a tissue-specific expression pattern.

VDR promotes testosterone synthesis in mouse Leydig cells via regulation of cholesterol side chain cleavage cytochrome P450 (Cyp11a1) expression

BACKGROUND

The vitamin D receptor (VDR) mediates the pleiotropic biological actions that include osteoporosis, immune responses and androgen synthesis.VDR is widely expressed in testis cells such as Leydig cells, Sertoli cells, and sperm. The levels of steroids are critical for sexual development. In the early stage of steroidogenesis, cholesterol is converted to pregnenolone (precursor of most steroid hormones) by cholesterol side-chain lyase (CYP11A1), which eventually synthesizes the male hormone testosterone.

OBJECTIVE

This study aims to reveal how VDR regulates CYP11A1 expression and affects testosterone synthesis in murine Leydig cells.

METHODS

The levels of VDR, CYP11A1 were determined by quantitative real-time polymerase chain reaction (RT-qPCR) or western blot. Targeted relationship between VDR and Cyp11a1 was evaluated by dual-luciferase reporter assay. The levels of testosterone concentrations in cell culture media serum by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Phylogenetic and motif analysis showed that the Cyp11a1 family had sequence loss, which may have special biological functions during evolution. The results of promoter prediction showed that vitamin D response element (VDRE) existed in the upstream promoter region of murine Cyp11a1. Dual-luciferase assay confirmed that VDR could bind candidate VDREs in upstream region of Cyp11a1, and enhance gene expression. Tissue distribution and localizatio analysis showed that Cyp11a1 was mainly expressed in testis, and dominantly existed in murine Leydig cells. Furthermore, over-expression VDR and CYP11A1 significantly increased testosterone synthesis in mice Leydig cells.

CONCLUSIONS

Active vitamin D3 (VD3) and Vdr interference treatment showed that VD3/VDR had a positive regulatory effect on Cyp11a1 expression and testosterone secretion. VDR promotes testosterone synthesis in male mice by up-regulating Cyp11a1 expression, which played an important role for male reproduction.

Protein kinase B (Akt) blockade inhibits LH/hCG-mediated 17,20-lyase, but not 17α-hydroxylase activity of Cyp17a1 in mouse Leydig cell steroidogenesis

Androgens are produced by adrenal and gonadal cells thanks to the action of specific enzymes. We investigated the role of protein kinase B (Akt) in the modulation of Δ4 steroidogenic enzymes' activity, in the mouse Leydig tumor cell line mLTC1. Cells were treated for 0-24 h with the 3 × 50% effective concentration of human luteinizing hormone (LH) and choriogonadotropin (hCG), in the presence and in the absence of the specific Akt inhibitor 3CAI. Cell signaling analysis was performed by bioluminescence resonance energy transfer (BRET) and Western blotting, while the expression of key target genes was investigated by real-time PCR. The synthesis of progesterone, 17α-hydroxy (OH)-progesterone and testosterone was measured by immunoassay. Control experiments for cell viability and caspase 3 activation were performed as well. We found that both hormones activated cAMP and downstream effectors, such as extracellularly-regulated kinase 1/2 (Erk1/2) and cAMP response element-binding protein (Creb), as well as Akt, and the transcription of Stard1, Hsd3b1, Cyp17a1 and Hsd17b3 genes, boosting the Δ4 steroidogenic pathway. Interestingly, Akt blockade decreased selectively Cyp17a1 expression levels, inhibiting its 17,20-lyase, but not the 17-hydroxylase activity. This effect is consistent with lower Cyp17a1 affinity to 17α-OH-progesterone than progesterone. As a result, cell treatment with 3CAI resulted in 17α-OH-progesterone accumulation at 16-24 h and decreased testosterone levels after 24 h. In conclusion, in the mouse Leydig cell line mLTC1, we found substantial Akt dependence of the 17,20-lyase activity and testosterone synthesis. Our results indicate that different intracellular pathways modulate selectively the dual activity of Cyp17a1.

Involvement of estrogen receptor alpha (ERα) and impairment of steroidogenesis after exposure to tris(2,3-dibromopropyl) isocyanurate (TBC) in mouse spermatogenic (GC-1 spg) cells in vitro

Good-quality reproductive cells are essential for reproduction. Endocrine disruptors are widely available in the environment and are known to have an adverse effect on spermatogenesis and steroidogenesis. One of them is tris(2,3-dibromopropyl) isocyanurate (TBC), i.e. one of the novel brominated flame retardants (NBFR). TBC is a widely distributed ingredient used in the production of flame retardants. Currently, it is known to affect the hormonal system, but the exact mechanism of its action is unknown. Therefore, the aim of the study was to determine whether TBC alone and in cotreatment with BHPI (estrogen receptor alpha antagonist) has an impact on the expression of nuclear receptors involved in the formation of steroid hormones, proteins, and enzymes responsible for steroidogenesis and the levels of steroid hormones (E2, P4, and T) in the GC-1 spg cell line as a mouse model of spermatogenic cells in vitro. Our results indicate that ERα is involved in the mechanism of TBC action, while no activation of PPARγ, AhR, and IGF-1R was observed. In addition, a decrease in the levels of most of the analyzed proteins and enzymes involved in steroid conversion was observed. Only Cyp19a1 was upregulated after TBC, BHPI, and TBC with BHPI cotreatment. In all the analyzed groups, a significant decrease in P4 and a subtle decrease in T and E2 were observed in the production and secretion of the hormones to the culture medium, compared to the control. The obtained results confirm the involvement of TBC in the dysregulation of steroid biosynthesis, which may affect male fertility.

Microwave-assisted synthesis of novel steroidal heterocyclic analogs as potent inhibitors of RANKL-induced osteoclastogenesis

Osteoporosis is a significant public health issue in our aging population. It is an excessive bone resorption condition brought on by osteoclastogenesis, which makes bones more brittle. In the present work, a series of novel heterosteroidal derivatives have been synthesized using the microwave technique and were evaluated as antiosteoclastogenic agents. The structures of the newly synthesized compounds have been confirmed using analytical and spectral data. The antiosteoclastogenic activity of the newly synthesized compounds was estimated in vitro against osteoclast-differentiated cells from the RAW 264.7 cell line. The pregnenolone dimer 10, the pyridinotestosterone derivative 2, and the phenylnicotinonitrile pregnenolone derivative 8a attained the most promising antiosteoclastogenic activity displaying IC50 (the half maximal inhibitory concentration) values of 5.45 ± 5.30, 11.88 ± 2.09, and 13.40 ± 3.00 µM, respectively, in comparison with dimethyl itaconate (IC50  = 17.76 ± 3.20 µM) and alendronate (IC50  = 4.48 ± 1.89 µM) as reference compounds. Finally, an in silico ADME (Absorption, Distribution, Metabolism, and Excretion) study was conducted to evaluate the synthesized compounds' pharmacokinetic and drug-likeness properties. The results manifested that almost all the investigated compounds' properties were compatible with the specified optimal range, which indicates their reassuring pharmacokinetic properties.

Microbial endocrinology: the mechanisms by which the microbiota influences host sex steroids

Recent progress in microbial endocrinology has propelled this field from initially providing correlational links to defining the mechanisms by which microbes influence systemic sex hormones. Importantly, the interaction between the gut-resident bacteria and host-secreted hormones has been shown to be critical for host development as well as hormone-mediated disease progression. This review investigates how microbes affect active sex hormone levels, with a focus on gut-associated bacteria hormonal modifications and the resulting host physiological status. Specifically, we focus on the ability of the microbiota to reactivate estrogens and deactivate androgens and thereby influence systemic levels of host hormones in a clinically significant manner.

Reduced urine pregnenolone concentration after clinical response in patients with depression: An open-label short-term prospective study

BACKGROUND

Identifying biological alterations in patients with depression, particularly those that differ between responders and non-responders, is of interest to clinical practice. Biomarker candidates involve neuroactive steroids, including pregnenolone (PREG) and allopregnanolone (ALLO). However, alterations in PREG and ALLO associated with treatment response are understudied. This study's main aim was to evaluate the effects of antidepressant treatment, clinical response, and treatment duration on PREG and ALLO in depression.

MATERIALS AND METHODS

In a 4-week, open-label trial, participants were allocated randomly to the venlafaxine (n = 27) or mirtazapine (n = 30) group. Urine concentrations of PREG and ALLO were assessed through gas chromatography-mass spectrometry. Participants collected night urine between 10:30 p.m. and 8:00 a.m. Two primary outcomes were analyzed. Firstly, the effect of treatment (mirtazapine or venlafaxine), clinical response (operationalized through the Hamilton Depression Rating Scale), and time (baseline compared to 28 days) on the urine concentrations of PREG or ALLO in depression. Finally, the effect of clinical response and time on the urine concentration of PREG or ALLO, independently of the antidepressant given (mirtazapine or venlafaxine). Linear mixed models were carried out.

RESULTS

There was no significant difference in PREG and ALLO concentrations between baseline and 28 days in responders and non-responders when investigating the venlafaxine or the mirtazapine group. However, we found a significant reduction of urine PREG concentration after 28 days of treatment in responders who received either venlafaxine or mirtazapine (estimate = -0.56; p = 0.016; 95CI [-1.003; -0.115]; Cohen's d = -0.61).

CONCLUSIONS

Our main results indicate that responders in depression show reduced urinary PREG concentrations after 4-weeks of therapy, independently of the antidepressant used. More studies are needed to confirm these findings.

CLICK-chemoproteomics and molecular dynamics simulation reveals pregnenolone targets and their binding conformations in Th2 cells

Pregnenolone (P5) is synthesized as the first bioactive steroid in the mitochondria from cholesterol. Clusters of differentiation 4 (CD4+) and Clusters of differentiation 8 (CD8+) immune cells synthesize P5 de novo; P5, in turn, play important role in immune homeostasis and regulation. However, P5's biochemical mode of action in immune cells is still emerging. We envisage that revealing the complete spectrum of P5 target proteins in immune cells would have multifold applications, not only in basic understanding of steroids biochemistry in immune cells but also in developing new therapeutic applications. We employed a CLICK-enabled probe to capture P5-binding proteins in live T helper cell type 2 (Th2) cells. Subsequently, using high-throughput quantitative proteomics, we identified the P5 interactome in CD4+ Th2 cells. Our study revealed P5's mode of action in CD4+ immune cells. We identified novel proteins from mitochondrial and endoplasmic reticulum membranes to be the primary mediators of P5's biochemistry in CD4+ and to concur with our earlier finding in CD8+ immune cells. Applying advanced computational algorithms and molecular simulations, we were able to generate near-native maps of P5-protein key molecular interactions. We showed bonds and interactions between key amino acids and P5, which revealed the importance of ionic bond, hydrophobic interactions, and water channels. We point out that our results can lead to designing of novel molecular therapeutics strategies.

The Sterol Transporter Npc2c Controls Intestinal Stem Cell Mitosis and Host-Microbiome Interactions in Drosophila

Cholesterol is necessary for all cells to function. The intracellular cholesterol transporters Npc1 and Npc2 control sterol trafficking and their malfunction leads to Neimann-Pick Type C disease, a rare disorder affecting the nervous system and the intestine. Unlike humans that encode single Npc1 and Npc2 transporters, flies encompass two Npc1 (Npc1a-1b) and eight Npc2 (Npc2a-2h) members, and most of the Npc2 family genes remain unexplored. Here, we focus on the intestinal function of Npc2c in the adult. We find that Npc2c is necessary for intestinal stem cell (ISC) mitosis, maintenance of the ISC lineage, survival upon pathogenic infection, as well as tumor growth. Impaired mitosis of Npc2c-silenced midguts is accompanied by reduced expression of Cyclin genes, and genes encoding ISC regulators, such as Delta, unpaired1 and Socs36E. ISC-specific Npc2c silencing induces Attacin-A expression, a phenotype reminiscent of Gram-negative bacteria overabundance. Metagenomic analysis of Npc2c-depleted midguts indicates intestinal dysbiosis, whereby decreased commensal complexity is accompanied by increased gamma-proteobacteria. ISC-specific Npc2c silencing also results in increased cholesterol aggregation. Interestingly, administration of the non-steroidal ecdysone receptor agonist, RH5849, rescues mitosis of Npc2c-silenced midguts and increases expression of the ecdysone response gene Broad, underscoring the role of Npc2c and sterols in ecdysone signaling. Assessment of additional Npc2 family members indicates potential redundant roles with Npc2c in ISC control and response to ecdysone signaling. Our results highlight a previously unidentified essential role of Npc2c in ISC mitosis, as well as an important role in ecdysone signaling and microbiome composition in the Drosophila midgut.

Polystyrene microplastics disrupt female reproductive health and fertility via sirt1 modulation in zebrafish (Danio rerio)

Microplastics (MPs) pollution poses an emerging threat to aquatic biota, which could hinder their physiological processes. Recently various evidence has demonstrated the toxic impacts of MPs on cellular and organismal levels, but still, the underlying molecular mechanism behind their toxicity remains ambiguous. The hypothalamic-pituitary-gonadal (HPG) axis regulates the synthesis and release of sex steroid hormones, and SIRT1 plays a vital role in this process. The current study aimed to elucidate the harmful effects of MPs on female reproduction via SIRT1 modulation. Healthy female zebrafish were exposed to different concentrations (50 and 500 µg/L) of polystyrene microplastics (PS-MPs). The results revealed a significant change in the gonadosomatic index (GSI) after exposure to PS-MPs. In addition, the decreased fecundity rate displayed an evident dosage effect, indicating that exposure to PS-MPs causes deleterious effects on fertilization. Furthermore, significantly enhanced levels of reactive oxygen species (ROS) and apoptotic signals through the TUNEL assay were evaluated in different treated groups. Moreover, morphological alterations in the gonads of zebrafish exposed to MPs were also observed through H&E staining. The subsequent change in plasma steroid hormone levels (E2/T ratio) showed an imbalance in hormonal homeostasis. Meanwhile, to follow PS-MPs' effects on the HPG axis via SIRT1 modulation and gene expression related to steroidogenesis, SIRT1/p53 pathway was evaluated through qPCR. The altered transcription levels of genes indicated the plausible interference of PS-MPs on the HPG axis function. Our in-silico molecular docking study proves that PS-MPs efficiently bind and inhibit endocrine receptors and SIRT1. Thus, these findings add to our understanding of the probable molecular mechanisms of reproductive impairment caused by PS-MPs in zebrafish.

Polycystic ovary syndrome: pathophysiology and therapeutic opportunities

Polycystic ovary syndrome is characterised by excessive levels of androgens and ovulatory dysfunction, and is a common endocrine disorder in women of reproductive age. Polycystic ovary syndrome arises as a result of polygenic susceptibility in combination with environmental influences that might include epigenetic alterations and in utero programming. In addition to the well recognised clinical manifestations of hyperandrogenism and ovulatory dysfunction, women with polycystic ovary syndrome have an increased risk of adverse mental health outcomes, pregnancy complications, and cardiometabolic disease. Unlicensed treatments have limited efficacy, mostly because drug development has been hampered by an incomplete understanding of the underlying pathophysiological processes. Advances in genetics, metabolomics, and adipocyte biology have improved our understanding of key changes in neuroendocrine, enteroendocrine, and steroidogenic pathways, including increased gonadotrophin releasing hormone pulsatility, androgen excess, insulin resistance, and changes in the gut microbiome. Many patients with polycystic ovary syndrome have high levels of 11-oxygenated androgens, with high androgenic potency, that might mediate metabolic risk. These advances have prompted the development of new treatments, including those that target the neurokinin-kisspeptin axis upstream of gonadotrophin releasing hormone, with the potential to lessen adverse clinical sequelae and improve patient outcomes.

The use of liquid chromatography-tandem mass spectrometry in newborn screening for congenital adrenal hyperplasia: improvements and future perspectives

Newborn screening for congenital adrenal hyperplasia using 17-hydroxyprogesterone by immunoassay remains controversial despite screening been available for almost 40 years. Screening is confounded by poor immunoassay specificity, fetal adrenal physiology, stress, and illness which can result in a large number of false positive screening tests. Screening programmes apply higher screening thresholds based on co-variates such as birthweight or gestational age but the false positive rate using immunoassay remains high. Mass spectrometry was first applied to newborn screening for congenital adrenal hyperplasia over 15 years ago. Elevated 17-hydroxprogesterone by immunoassay can be retested with a specific liquid chromatography tandem mass spectrometry assay that may include additional steroid markers. Laboratories register with quality assurance programme providers to ensure accurate steroid measurements. This has led to improvements in screening but there are additional costs and added laboratory workload. The search for novel steroid markers may inform further improvements to screening. Studies have shown that 11-oxygenated androgens are elevated in untreated patients and that the adrenal steroidogenesis backdoor pathway is more active in babies with congenital adrenal hyperplasia. There is continual interest in 21-deoxycortisol, a specific marker of 21-hydroxylase deficiency. The measurement of androgenic steroids and their precursors by liquid chromatography tandem mass spectrometry in bloodspots may inform improvements for screening, diagnosis, and treatment monitoring. In this review, we describe how liquid chromatography tandem mass spectrometry has improved newborn screening for congenital adrenal hyperplasia and explore how future developments may inform further improvements to screening and diagnosis.

α-Linolenic acid-regulated testosterone biosynthesis via activation of the JNK-SF-1 signaling pathway in primary rooster Leydig cells

As a functional fatty acid, α-linolenic acid (ALA) is essential in promoting animal testosterone biosynthesis. This study investigated the effects of ALA on testosterone biosynthesis and the possible mechanism underlying the signaling pathway in primary Leydig cells of the rooster.

METHODS

Primary rooster Leydig cells were treated with ALA (0, 20, 40, or 80 μmol/L) or pretreated with a p38 inhibitor (50 μmol/L), a c-Jun NH2-terminal kinase (JNK) inhibitor (20 μmol/L), or an extracellular signal-regulated kinase (ERK) inhibitor (20 μmol/L) before ALA treatment. Testosterone content in the conditioned culture medium was detected using an enzyme-linked immunosorbent assay (ELISA). The expression of steroidogenic enzymes and JNK-SF-1 signaling pathway factors was detected using real-time fluorescence quantitative PCR (qRT-PCR).

RESULTS

Supplementation with ALA significantly increased testosterone secretion within culture media (P < 0.05), and the optimized dose was 40 μmol/L. Compared with the control group, steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) mRNA expression significantly increased (P < 0.05) in the 40 μmol/L ALA group; 17-hydroxylase/c17-20 lyase (P450c17) and p38 mRNA expressions were not significantly different in the 40 μmol/L ALA group; ERK and JNK mRNA expressions were significantly upregulated (P < 0.05) in 40 μmol/L ALA group. In the inhibitor group, testosterone levels were significantly downregulated (P < 0.05). Compared with the 40 μmol/L ALA group, StAR, P450scc, and P450c17 mRNA expressions were significantly decreased (P < 0.05), and 3β-HSD mRNA expression in the p38 inhibitor group did not change; StAR, P450scc, and 3β-HSD mRNA expressions were significantly decreased (P < 0.05), and P450c17 mRNA expression in ERK inhibitor group did not change; StAR, P450scc, 3β-HSD, and P450c17 mRNA expressions were significantly decreased (P < 0.05) in JNK inhibitor group. Additionally, the increased steroidogenic factor 1 (SF-1) gene expression levels induced by ALA were reversed when the cells were pre-incubated with JNK and ERK inhibitors. The levels in the JNK inhibitor group were significantly lower than those in the control group (P < 0.05).

CONCLUSION

ALA may promote testosterone biosynthesis by activating the JNK-SF-1 signaling pathway to upregulate StAR, P450scc, 3β-HSD, and P450c17 expression in primary rooster Leydig cells.

Occurrence and conversion of progestogens and androgens are conserved in land plants

Progestogens and androgens have been found in many plants, but little is known about their biosynthesis and the evolution of steroidogenesis in these organisms. Here, we show that the occurrence and biosynthesis of progestogens and androgens are conserved across the viridiplantae lineage. An UHPLC-ESI-MS/MS method allowed high-throughput analysis of the occurrence and chemical conversion of progestogens and androgens in 41 species across the green plant lineage. Dehydroepiandrosterone, testosterone, and 5α-dihydrotestosterone are plants' most abundant mammalian-like steroids. Progestogens are converted into 17α-hydroxyprogesterone and 5α-pregnane-3,20-dione. Androgens are converted into testosterone and 5α-dihydrotestosterone. 17,20-Lyases, essential for converting progestogens to androgens, seem to be most effective in monocot species. Our data suggest that the occurrence of progestogens and androgens is highly conserved in plants, and their biosynthesis might favor a route using the Δ4 pathway.

The Roles of Autophagy in the Genesis and Development of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common and frequent disease and always leads endocrine and metabolic disorder among women in reproductive age. Ovary is the main organ involved in polycystic ovary syndrome, and its function impairment will lead to reproductive dysfunction. Some recent studies have demonstrated that autophagy plays an important role in the pathogenesis of PCOS, and there are many different mechanisms that affect autophagy and the occurrence of PCOS, and they provide a new direction for us to predict the mechanism of PCOS. In this review, we discuss the role of autophagy in different ovarian cells: granulosa cells, oocytes, and theca cells, and introduce the important role that they play in the progress of PCOS. The main purpose of this review is to provide the research background and some relevant suggestions for our future work in autophagy and help us better explore the pathogenesis and autophagy mechanisms of PCOS. Furthermore, it will help us gain a new insight of the pathophysiology and treatment of PCOS.

Influence of cholesterol on kinetic parameters for human aromatase (P450 19A1) in phospholipid nanodiscs

Cholesterol, a significant constituent of the endoplasmic reticulum membrane, exerts a substantial effect on the membrane's biophysical and mechanical properties. Cholesterol, however, is often neglected in model systems used to study membrane-bound proteins. For example, the influence of cholesterol on the enzymatic functions of type 2 cytochromes P450, which require a phospholipid bilayer and the redox partner P450-oxidoreductase (POR) for activity, are rarely investigated. Human aromatase (P450 19A1) catalyzes three sequential oxygenations of 19‑carbon steroids to estrogens and is widely expressed across various tissues, which are characterized by varying cholesterol compositions. Our study examined the impact of cholesterol on the functionality of the P450 19A1 complex with POR. Nanodiscs containing P450 19A1 with 20% cholesterol/80% phospholipid had similar rates and affinity of androstenedione binding as phospholipid-only P450 19A1 nanodiscs, and rates of product formation were indistinguishable among these conditions. In contrast, the rate of the first electron transfer from POR to P450 19A1 was 3-fold faster in cholesterol-containing nanodiscs than in phospholipid-only nanodiscs. These results suggest that cholesterol influences some aspects of POR interaction with P450 19A1 and might serve as an additional regulatory mechanism in this catalytic system.

Challenges and Opportunities in P450 Research on the Eye

Of the 57 cytochrome P450 enzymes found in humans, at least 30 have ocular tissues as an expression site. Yet knowledge of the roles of these P450s in the eye is limited, in part because only very few P450 laboratories expanded their research interests to studies of the eye. Hence the goal of this review is to bring attention of the P450 community to the eye and encourage more ocular studies. This review is also intended to be educational for eye researchers and encourage their collaborations with P450 experts. The review starts with a description of the eye, a fascinating sensory organ, and is followed by sections on ocular P450 localizations, specifics of drug delivery to the eye, and individual P450s, which are grouped and presented based on their substrate preferences. In sections describing individual P450s, available eye-relevant information is summarized and concluded by the suggestions on the opportunities in ocular studies of the discussed enzymes. Potential challenges are addressed as well. The conclusion section outlines several practical suggestions on how to initiate eye-related research. SIGNIFICANCE STATEMENT: This review focuses on the cytochrome P450 enzymes in the eye to encourage their ocular investigations and collaborations between P450 and eye researchers.

Neurosteroids and the mesocorticolimbic system

The mesocorticolimbic system coordinates executive functions, such as working memory and behavioral flexibility. This circuit includes dopaminergic projections from the ventral tegmental area to the nucleus accumbens and medial prefrontal cortex. In this review, we summarize evidence that cells in multiple nodes of the mesocorticolimbic system produce neurosteroids (steroids synthesized in the nervous system) and express steroid receptors. Here, we focus on neuroandrogens (androgens synthesized in the nervous system), neuroestrogens (estrogens synthesized in the nervous system), and androgen and estrogen receptors. We also summarize how (neuro)androgens and (neuro)estrogens affect dopamine signaling in the mesocorticolimbic system and regulate executive functions. Taken together, the data suggest that steroids produced in the gonads and locally in the brain modulate higher-order cognition and executive functions.

Deciphering Cellular Heterogeneity and Communication Patterns in Porcine Antral Follicles by Single-Cell RNA Sequencing

The antral follicle stage is a critical period in mammalian oocyte maturation, marked by complex interactions between oocyte development and neighboring granulosa cells. Understanding the heterogeneity and communication patterns of granulosa cells within antral follicles is crucial for deciphering their roles in follicle development and oocyte maturation. Here, we employed single-cell RNA-sequencing to explore the molecular and cellular characteristics of porcine antral follicles. Our analysis revealed distinct subpopulations within mural and cumulus granulosa cells, indicating diverse cellular states and functions within the follicles. Functional enrichment analysis unveiled the involvement of specific subpopulations in steroid biosynthesis, cumulus expansion, and cellular communication. Moreover, comparing mature and less mature follicles highlighted differences in cell distribution and functions, indicating developmental-specific variations. Our findings shed light on the intricate cellular heterogeneity and communication network within porcine antral follicles, providing valuable insights into the regulation of follicle development and oocyte maturation in pigs. These results hold promise for improving pig reproductive efficiency and advancing human reproductive medicine.

Statin treatment is not associated with an increased risk of adrenal insufficiency in real-world setting

Introduction

Statins could reduce the synthesis of steroid hormones, thereby could cause adrenal insufficiency. We investigated this risk in a large nationwide database.

Methods

We conducted a nested case-control study using a cohort of individuals affiliated to the French health insurance system in 2010, ≥18y and without adrenal insufficiency history. Each case had a first event of adrenal insufficiency between 2015 and 2017 and was matched to up to ten controls on age, sex, and prior treatment with corticosteroids. Statin exposure was measured over the five years preceding the index date, considering a six-month censoring lag-time. Association was estimated using a conditional logistic regression adjusted for confounders included in a disease risk score. Analyses were stratified on age, sex and corticosteroid history of use.

Results

4 492 cases of adrenal insufficiency were compared with 44 798 controls (median age 66y, 58% women), of which 39% vs. 33% were exposed to statins, respectively. No association between statin use and adrenal insufficiency was found when adjusting the model for confounders (adjusted odds ratio 0.98; 95% confidence interval 0.90-1.05). These results were consistent regardless of the exposure definition and stratifications considered.

Conclusion

Statin-related adrenal insufficiency risk, if any, seems to be very limited and does not compromise the benefit of statin treatment.

Nuclear Estrogen Receptors in Prostate Cancer: From Genes to Function

Estrogens are almost ubiquitous steroid hormones that are essential for development, metabolism, and reproduction. They exert both genomic and non-genomic action through two nuclear receptors (ERα and ERβ), which are transcription factors with disregulated functions and/or expression in pathological processes. In the 1990s, the discovery of an additional membrane estrogen G-protein-coupled receptor augmented the complexity of this picture. Increasing evidence elucidating the specific molecular mechanisms of action and opposing effects of ERα and Erβ was reported in the context of prostate cancer treatment, where these issues are increasingly investigated. Although new approaches improved the efficacy of clinical therapies thanks to the development of new molecules targeting specifically estrogen receptors and used in combination with immunotherapy, more efforts are needed to overcome the main drawbacks, and resistance events will be a challenge in the coming years. This review summarizes the state-of-the-art on ERα and ERβ mechanisms of action in prostate cancer and promising future therapies.

CRISPR/Cas9-mediated activation of NR5A1 steers female human embryonic stem cell-derived bipotential gonadal-like cells towards a steroidogenic cell fate

The nuclear receptor subfamily 5 group A member 1 (NR5A1), encoding steroidogenic factor 1 (SF-1), has been identified as a critical factor in gonadal development in animal studies. A previous study of ours suggested that upregulation of NR5A1 during early gonadal differentiation in male (46,XY) human pluripotent stem cells steers the cells into a more mature gonadal cell type. However, the detailed role of NR5A1 in female gonadal differentiation has yet to be determined. In this study, by combining the processes of gonadal differentiation and conditional gene activation, we show that NR5A1 induction predominantly upregulates the female gonadal marker inhibin subunit α (INHA) and steroidogenic markers steroidogenic acute regulatory protein (STAR), cytochrome P450 family 11 subfamily A member 1 (CYP11A1), cytochrome P450 family 17 subfamily A member 1 (CYP17A1), hydroxy-delta-5-steroid dehydrogenase (HSD3B2) and hydroxysteroid 17-beta dehydrogenase 1 (HSD17B1). In contrast, NR5A1 induction did not seem to affect the bipotential gonadal markers gata binding protein 4 (GATA4) and Wilms' tumour suppressor 1 (WT1) nor the female gonadal markers r-spondin 1 (RSPO1) and wnt family member 4 (WNT4). Differentially expressed genes were highly associated with adrenal and ovarian steroidogenesis pathways. Moreover, time-series analysis revealed different dynamic changes between male and female induced samples, where continuously upregulated genes in female gonadal differentiation were mostly associated with adrenal steroidogenesis. Thus, in contrast to male gonadal differentiation, NR5A1 is necessary but not sufficient to steer human embryonic stem cell (hESC)-derived bipotential gonadal-like cells towards a more mature somatic, female cell fate. Instead, it seems to direct bipotential gonadal-like cells more towards a steroidogenic-like cell population. The information obtained in this study helps in elucidating the role of NR5A1 in gonadal differentiation of a female stem cell line.

Virtual screening and biological evaluation to identify pharmaceuticals potentially causing hypertension and hypokalemia by inhibiting steroid 11β-hydroxylase

Several drugs were found after their market approval to unexpectedly inhibit adrenal 11β-hydroxylase (CYP11B1)-dependent cortisol synthesis. Known side-effects of CYP11B1 inhibition include hypertension and hypokalemia, due to a feedback activation of adrenal steroidogenesis, leading to supraphysiological concentrations of 11-deoxycortisol and 11-deoxycorticosterone that can activate the mineralocorticoid receptor. This results in potassium excretion and sodium and water retention, ultimately causing hypertension. With the risk known but usually not addressed in preclinical evaluation, this study aimed to identify drugs and drug candidates inhibiting CYP11B1. Two conceptually different virtual screening methods were combined, a pharmacophore based and an induced fit docking approach. Cell-free and cell-based CYP11B1 activity measurements revealed several inhibitors with IC50 values in the nanomolar range. Inhibitors include retinoic acid metabolism blocking agents (RAMBAs), azole antifungals, α2-adrenoceptor ligands, and a farnesyltransferase inhibitor. The active compounds share a nitrogen atom embedded in an aromatic ring system. Structure activity analysis identified the free electron pair of the nitrogen atom as a prerequisite for the drug-enzyme interaction, with its pKa value as an indicator of inhibitory potency. Another important parameter is drug lipophilicity, exemplified by etomidate. Changing its ethyl ester moiety to a more hydrophilic carboxylic acid group dramatically decreased the inhibitory potential, most likely due to less efficient cellular uptake. The presented work successfully combined different in silico and in vitro methods to identify several previously unknown CYP11B1 inhibitors. This workflow facilitates the identification of compounds that inhibit CYP11B1 and therefore pose a risk for inducing hypertension and hypokalemia.

Systemic Proteome Phenotypes Reveal Defective Metabolic Flexibility in Mecp2 Mutants

Genes mutated in monogenic neurodevelopmental disorders are broadly expressed. This observation supports the concept that monogenic neurodevelopmental disorders are systemic diseases that profoundly impact neurodevelopment. We tested the systemic disease model focusing on Rett syndrome, which is caused by mutations in MECP2. Transcriptomes and proteomes of organs and brain regions from Mecp2-null mice as well as diverse MECP2-null male and female human cells were assessed. Widespread changes in the steady-state transcriptome and proteome were identified in brain regions and organs of presymptomatic Mecp2-null male mice as well as mutant human cell lines. The extent of these transcriptome and proteome modifications was similar in cortex, liver, kidney, and skeletal muscle and more pronounced than in the hippocampus and striatum. In particular, Mecp2- and MECP2-sensitive proteomes were enriched in synaptic and metabolic annotated gene products, the latter encompassing lipid metabolism and mitochondrial pathways. MECP2 mutations altered pyruvate-dependent mitochondrial respiration while maintaining the capacity to use glutamine as a mitochondrial carbon source. We conclude that mutations in Mecp2/MECP2 perturb lipid and mitochondrial metabolism systemically limiting cellular flexibility to utilize mitochondrial fuels.

FDX1 regulates cellular protein lipoylation through direct binding to LIAS

Ferredoxins are a family of iron-sulfur (Fe-S) cluster proteins that serve as essential electron donors in numerous cellular processes that are conserved through evolution. The promiscuous nature of ferredoxins as electron donors enables them to participate in many metabolic processes including steroid, heme, vitamin D, and Fe-S cluster biosynthesis in different organisms. However, the unique natural function(s) of each of the two human ferredoxins (FDX1 and FDX2) are still poorly characterized. We recently reported that FDX1 is both a crucial regulator of copper ionophore-induced cell death and serves as an upstream regulator of cellular protein lipoylation, a mitochondrial lipid-based post-translational modification naturally occurring on four mitochondrial enzymes that are crucial for TCA cycle function. Here we show that FDX1 directly regulates protein lipoylation by binding the lipoyl synthase (LIAS) enzyme promoting its functional binding to the lipoyl carrier protein GCSH and not through indirect regulation of cellular Fe-S cluster biosynthesis. Metabolite profiling revealed that the predominant cellular metabolic outcome of FDX1 loss of function is manifested through the regulation of the four lipoylation-dependent enzymes ultimately resulting in loss of cellular respiration and sensitivity to mild glucose starvation. Transcriptional profiling established that FDX1 loss-of-function results in the induction of both compensatory metabolism-related genes and the integrated stress response, consistent with our findings that FDX1 loss-of-function is conditionally lethal. Together, our findings establish that FDX1 directly engages with LIAS, promoting its role in cellular protein lipoylation, a process essential in maintaining cell viability under low glucose conditions.

Global gene expression analysis reveals a subtle effect of DEHP in human granulosa cell line HGrC1

Di(2-ethylhexyl) phthalate (DEHP) is an endocrine disruptor that exerts anti-steroidogenic effects in human granulosa cells; however, the extent of this effect depends on the concentration of DEHP and granulosa cell models used for exposure. The objective of this study was to identify the effects of low- and high-dose DEHP exposure in human granulosa cells. We exposed human granulosa cell line HGrC1 to 3 nM and 25 μM DEHP for 48 h. The whole genome transcriptome was analyzed using the DNBSEQ sequencing platform and bioinformatics tools. The results revealed that 3 nM DEHP did not affect global gene expression, whereas 25 µM DEHP affected the expression of only nine genes in HGrC1 cells: ABCA1, SREBF1, MYLIP, TUBB3, CENPT, NUPR1, ASS1, PCK2, and CTSD. We confirmed the downregulation of ABCA1 mRNA and SREBP-1 protein (encoded by the SREBF1 gene), both involved in cholesterol homeostasis. Despite these changes, progesterone production remained unaffected in low- and high-dose DEHP-exposed HGrC1 cells. The high concentration of DEHP decreased the levels of ABC1A mRNA and SREBP-1 protein and prevented the upregulation of STAR, a protein involved in progesterone synthesis, in forskolin-stimulated HGrC1 cells; however, the observed changes were not sufficient to alter progesterone production in forskolin-stimulated HGrC1 cells. Overall, this study suggests that acute exposure to low concentration of DEHP does not compromise the function of HGrC1 cells, whereas high concentration causes only subtle effects. The identified nine novel targets of high-dose DEHP require further investigation to determine their role and importance in DEHP-exposed human granulosa cells.

Sex/gender differences in cognitive abilities

Sex/gender differences in cognitive sciences are riddled by conflicting perspectives. At the center of debates are clinical, social, and political perspectives. Front and center, evolutionary and biological perspectives have often focused on 'nature' arguments, while feminist and constructivist views have often focused on 'nurture arguments regarding cognitive sex differences. In the current narrative review, we provide a comprehensive overview regarding the origins and historical advancement of these debates while providing a summary of the results in the field of sexually polymorphic cognition. In so doing, we attempt to highlight the importance of using transdisciplinary perspectives which help bridge disciplines together to provide a refined understanding the specific factors that drive sex differences a gender diversity in cognitive abilities. To summarize, biological sex (e.g., birth-assigned sex, sex hormones), socio-cultural gender (gender identity, gender roles), and sexual orientation each uniquely shape the cognitive abilities reviewed. To date, however, few studies integrate these sex and gender factors together to better understand individual differences in cognitive functioning. This has potential benefits if a broader understanding of sex and gender factors are systematically measured when researching and treating numerous conditions where cognition is altered.

3βHSD activity saturates at physiological substrate concentrations in intact cells

BACKGROUND

Conversion of adrenally produced dehydroepiandrosterone (DHEA) to the potent androgen dihydrotestosterone (DHT) is an important mechanism by which prostate cancer reaches castration resistance. At the start of this pathway is a branch point at which DHEA can be converted to Δ4 -androstenedione by the enzyme 3β-hydroxysteroid dehydrogenase (3βHSD) or to Δ5 -androstenediol by 17βHSD. To better understand this process, we studied the kinetics of these reactions in cells.

METHODS

Prostate cancer cells (LNCaP cell line) were incubated with steroids (DHEA and Δ5 -androstenediol) over a range of concentrations and the steroid metabolism reaction products were measured by mass spectrometry or by high-performance liquid chromatography to determine reaction kinetics. To confirm the generalizability of results, experiments were also performed in JEG-3 placental choriocarcinoma cells.

RESULTS

The two reactions displayed very different saturation profiles, with only the 3βHSD-catalyzed reaction beginning to saturate within a physiological substrate concentration range. Strikingly, incubating LNCaP cells with low (in the ~10 nM range) concentrations of DHEA resulted in a large majority of the DHEA undergoing 3βHSD-catalyzed conversion to Δ4 -androstenedione, whereas high concentrations of DHEA (in the 100s of nM range) resulted in most of the DHEA undergoing 17βHSD-catalyzed conversion to Δ5 -androstenediol.

CONCLUSION

Contrary to expectations from previous studies that used purified enzyme, cellular metabolism of DHEA by 3βHSD begins to saturate in the physiological concentration range, suggesting that fluctuations in DHEA concentrations could be buffered at the downstream active androgen level.

Bacteria in cancer initiation, promotion and progression

Cancer cells originate from a series of acquired genetic mutations that can drive their uncontrolled cell proliferation and immune evasion. Environmental factors, including the microorganisms that colonize the human body, can shift the metabolism, growth pattern and function of neoplastic cells and shape the tumour microenvironment. Dysbiosis of the gut microbiome is now recognized as a hallmark of cancer by the scientific community. However, only a few microorganisms have been identified that directly initiate tumorigenesis or skew the immune system to generate a tumour-permissive milieu. Over the past two decades, research on the human microbiome and its functionalities within and across individuals has revealed microbiota-focused strategies for health and disease. Here, we review the evolving understanding of the mechanisms by which the microbiota acts in cancer initiation, promotion and progression. We explore the roles of bacteria in gastrointestinal tract malignancies and cancers of the lung, breast and prostate. Finally, we discuss the promises and limitations of targeting or harnessing bacteria in personalized cancer prevention, diagnostics and treatment.

Computational prediction and analysis of targeting 17-beta-hydroxysteroid dehydrogenase (17-beta-HSD1) with natural products for colorectal cancer treatment

Colorectal cancer (CRC) is a type of cancer that occurs in the colon or rectum and kills millions of people each year. Steroid hormones are interconverted between their potent, high-affinity forms by using 17-beta hydroxysteroid dehydrogenase for their respective receptors in these tissues, with a high probability of random genetic errors. Currently, 17-beta-HSD1 studies have revealed the role of steroid metabolism in the development and proliferation of colorectal cancer. However, there is little information on how to target this enzyme with either modern medicine or natural products. In this study, we looked at 17-beta-HSD1 as a target for treating CRC development and proliferation using selected plant metabolites from previous studies. Plants are used to produce medicinal and novel bioactive compounds that are used to treat different infection. They primarily demonstrated anti-cancer effects through the regulation of cancer-related proteins, epigenetic factors and reactive oxygenase species. The study utilized Avogadro, ADMET lab 2.0, SWISS-MODEL, AutoDock, and Gromacs. Five lead molecules were chosen from a pool of plant metabolites based on their affinity for the 17-beta-HSD1 enzyme. Furthermore, two bind with high affinity are resveratrol (DG 11.29 kcal/mol) and folate (DG 12.23 kcal/mol) with low Ki values, while the rest binds with moderate affinity. Molecular dynamic simulation results also revealed that the folate-17-beta-HSD complex and reserverol- 17-beta-HSD1 complex maintained a stable conformation until the end of 100 ns. As a result, reserverol and folate could be used as lead molecules to target 17-beta-HSD1 and provide a promising starting point for further in vivo research.Communicated by Ramaswamy H. Sarma.

Effects of exposure to the explosive and environmental pollutant 2,4,6-trinitrotoluene on ovarian follicle development in rats

Although 2,4,6-trinitrotoluene (TNT) is a dangerous carcinogen in environmental pollution, information on the reproductive effects of TNT explosive contamination is limited. To explore the possible ovarian effects, TNT explosive-exposed rat models were established, and Wistar female rats were exposed to low and high TNT (40 g and 80 g, air and internal) explosives. After a month of exposure, the estrous cycle, ovarian histopathology, and follicle counting were conducted. Serum hormones follicle-stimulating hormone (FSH), luteinizing hormone (LH), anti-Müllerian hormone (AMH), progesterone, testosterone, and estradiol were detected, and the mRNA and protein expression of steroidogenic enzymes were measured. The results showed that the diestrus phase duration was significantly (P < 0.05) increased in the high TNT-exposed groups. In addition, the proportions of preantral follicles were significantly (P < 0.05) decreased in the high TNT-exposed groups, as well as the proportions of atretic follicles. The serum estradiol levels were significantly (P < 0.05) increased, and the follicle-stimulating hormone and luteinizing hormone levels were significantly (P < 0.05) decreased in the high TNT-exposed groups. The mRNA levels of steroidogenic acute regulatory protein (Star), cytochrome P450 cholesterol side chain cleavage (Cyp11a1, Cyp17a1 and Cyp19a1), hydroxysteroid dehydrogenase 3b (Hsd3b) and steroidogenic factor-1 (SF-1) were significantly (P < 0.05) increased in the TNT-exposed groups. The protein levels of Star, Cyp11a1 and Hsd3b were increased (P < 0.05) in the TNT-exposed groups. These results indicate that the exposure of rats to TNT explosive can subsequently affect ovarian follicle development, suggesting that the mechanism may involve disrupting steroidogenesis.

Biosynthesis of estetrol in human pregnancy: Potential pathways

Estetrol (E4) has emerged as a novel and highly promising estrogen for therapeutic use. E4 is a weak natural estrogen produced only in pregnancy. Because of its novelty, there is considerable interest by clinicians in how it is produced in pregnancy. Although the fetal liver plays a key role in its production, the placenta is also involved. A current view is that estradiol (E2) formed in the placenta enters the fetal compartment and is then rapidly sulfated. E2 sulfate then undergoes 15α-/16α-hydroxylation in the fetal liver thereby forming E4 sulfate (phenolic pathway). However, another pathway involving 15α,16α-dihydroxy-DHEAS formed in the fetal liver and converted to E4 in the placenta also plays a significant role (neutral pathway). It is not known which pathway predominates, but both pathways appear to be important in E4 biosynthesis. In this commentary, we summarize the well-established pathways in the formation of estrogens in the nonpregnant and pregnant female. We then review what is known about the biosynthesis of E4 and describe the 2 proposed pathways involving the fetus and placenta.

Changes of androgen and corticosterone metabolites excretion and conversion in cystic fibrosis

Cystic fibrosis (CF) is a life-threatening inherited disease related to a mutation in the CFTR gene, that leads to serious health complications such as chronic pulmonary infections, pancreatic insufficiency, dysfunction of the sweat glands and reproductive system. For the first time, we have described the profile of corticosterone and androgen metabolites in urine, as well as the activity of enzymes involved in steroid genesis and metabolism in people with CF, using gas chromatography/mass spectrometry. A significant reduction in the excretion of most of the measured metabolites in CF was found. These differences were observed in the group of progestagen metabolites, as well as among metabolites of corticosterone and androgens. We revealed higher activities of 17β-hydroxysteroid dehydrogenase and 17,20-lyase in the Δ4 pathway compared with controls, what can promote the androgen synthesis through the backdoor androgen pathway. We have also found the increased conversion activity of 11-oxyganated steroids by 5a-reductase in backdoor pathway. Levels of the most potent and vital androgens (testosterone and dihydrotestosterone) are comparable in both groups. However, the excretion of dehydroepiandrosterone was lower in CF. Decreased cholesterol lipoprotein levels may contribute to limited intracellular cholesterol supply and reduced adrenal steroidogenesis in CF individuals. Changes in the activity of some steroidogenesis enzymes may suggest the presence of some peripheral adaptive mechanisms in CF to maintain androgen balance in the body despite the limited sufficiency of secretion by the adrenal cortex.

Aire drives steroid hormone biosynthesis by medullary thymic epithelial cells

Thymic epithelial cells (TECs) produce glucocorticoids, which antagonize negative selection of autoreactive thymocytes and promote a competent T cell antigen-specific repertoire. To characterize their source, we generated a knock-in reporter mouse in which endogenous Cyp11b1, the final enzyme in de novo production of active glucocorticoids, was fluorescently tagged with mScarlet. Here, we find that Cyp11b1 is expressed in medullary TECs (mTECs) but not cortical TECs or other cells in the thymus. A distinct characteristic of mTECs is the presence of Aire, a transcription factor that drives expression of tissue-restricted antigens (TRAs) important for establishing immune tolerance. Cyp11b1 expression was highest in Aire+ mTECs, lower in post-Aire mTECs, and absent in mTECs of Aire-deficient mice. Transcriptomic analyses found that multiple enzymatic biosynthetic pathways are expressed specifically in mTECs and are also Aire dependent. In particular, we found that the thymus expresses messenger RNA for enzymes that catalyze production of many bioactive steroids and that glucocorticoids and sex steroids were secreted by cultured thymi. Expression of the transcripts for these genes and production of their final steroid products were markedly reduced in the absence of Aire. Thus, in addition to its well-established role in inducing TRAs that promote negative selection, Aire has an additional and contrary function of inducing glucocorticoids that antagonize negative selection, which together may expand and enhance the TCR repertoire. Furthermore, because Aire drives expression of multiple enzymes responsible for production of other non-gene-encoded bioactive molecules, it might have yet other roles in thymus development and function.

Effects of Maternal Cigarette Smoking on Trace Element Levels and Steroidogenesis in the Maternal-Placental-Fetal Unit

This study evaluates the interaction of toxic elements cadmium (Cd) and lead (Pb) due to exposure from cigarette smoking, essential elements, and steroidogenesis in the maternal-placental-fetal unit. In a cohort of 155 healthy, postpartum women with vaginal term deliveries in clinical hospitals in Zagreb, Croatia, samples of maternal blood/serum and urine, placental tissue, and umbilical cord blood/serum were collected at childbirth. The biomarkers determined were concentrations of Cd, Pb, iron (Fe), zinc (Zn), copper (Cu), and selenium (Se), and steroid hormones progesterone and estradiol in maternal and umbilical cord blood and the placenta. Three study groups were designated based on self-reported data on cigarette smoking habits and confirmed by urine cotinine levels: never smokers (n = 71), former smokers (n = 48), and active smokers (n = 36). Metal(loid)s, steroid hormones, urine cotinine, and creatinine levels were analyzed by ICP-MS, ELISA, GC-MS, and spectrophotometry. Cigarette smoking during pregnancy was associated with increased Cd levels in maternal, placental, and fetal compartments, Pb in the placenta, and with decreased Fe in the placenta. In active smokers, decreased progesterone and estradiol concentrations in cord blood serum were found, while sex steroid hormones did not change in either maternal serum or placenta. This study provides further evidence regarding toxic and essential metal(loid) interactions during prenatal life, and new data on sex steroid disruption in cord serum related to cigarette smoking. The results indicate that umbilical cord sex steroid levels may be a putative early marker of developmental origins of the future burden of disease related to harmful prenatal exposure to cigarette smoke.