Analysis and characteristics of multiple types of human 17beta-hydroxysteroid dehydrogenase

Psoralen prevents the inactivation of estradiol and treats osteoporosis via covalently targeting HSD17B2

ETHNOPHARMACOLOGICAL RELEVANCE

Psoralea corylifolia L. seeds (P. corylifolia), popularly known as Buguzhi in traditional Chinese medicine, are often used to treat osteoporosis in China. Psoralen (Pso) is the key anti-osteoporosis constituent in P. corylifolia, however, its targets and mechanism of action are still unclear.

AIM OF THE STUDY

The purpose of this study was to explore the interaction between Pso and 17-β hydroxysteroid dehydrogenase type 2 (HSD17B2), an estrogen synthesis-related protein that inhibits the inactivation of estradiol (E2) to treat osteoporosis.

MATERIALS AND METHODS

Tissue distribution of Pso was analyzed by in-gel imaging after oral administration of an alkynyl-modified Pso probe (aPso) in mice. The target of Pso in the liver was identified and analyzed using chemical proteomics. Co-localization and cellular thermal shift assays (CETSA) were used to verify the key action targets. To detect the key pharmacophore of Pso, the interaction of Pso and its structural analogs with HSD17B2 was investigated by CETSA, HSD17B2 activity assay, and in-gel imaging determination. Target competitive test, virtual docking, mutated HSD17B2 activity, and CETSA assay were used to identify the binding site of Pso with HSD17B2. A mouse model of osteoporosis was established by ovariectomies, and the efficacy of Pso in vivo was confirmed by micro-CT, H&E staining, HSD17B2 activity, and bone-related biochemical assays.

RESULTS

Pso regulated estrogen metabolism by targeting HSD17B2 in the liver, with the α, β-unsaturated ester in Pso being the key pharmacophore. Pso significantly suppressed HSD17B2 activity by irreversibly binding to Lys236 of HSD17B2 and preventing NAD⁺ from entering the binding pocket. In vivo studies in ovariectomized mice revealed that Pso could inhibit HSD17B2 activity, prevent the inactivation of E2, increase levels of endogenous estrogen, improve bone metabolism-related indices, and play a role in anti-osteoporosis.

CONCLUSIONS

Pso covalently binds to Lys236 of HSD17B2 in hepatocytes to prevent the inactivation of E2, thereby aiding in the treatment of osteoporosis.

Protein-protein networks analysis of differentially expressed genes unveils the key phenomenon of biological process with respect to reproduction in endangered catfish, C. Magur

Clarias magur (magur) is an important freshwater catfish with high potential in the aquaculture sector in its geographical ranges of distribution. One of the impediments to realise its full aquaculture potential is the lack of understanding key genes involved in its reproduction pathways. Nonetheless, very limited information is available on brain and gonads, with respect to reproduction related issues of magur at molecular level. The present study was aimed at understanding the interaction of the brain-gonad system by analysing differentially expressed genes (DEG) in brains and gonads of male and female magur using a protein-protein network interaction study. In brief, 641, 541, 225 and 245 DEGs, respectively, in ovary, testis and female brain and male-brain of magur were used as input in String database 11.0 and Cytoscape v 3.8.0 plug-in Network Analyzer for PPI network construction followed by network superimposition, network merging and analysis. A total of 13 key genes in female brain & ovary and 12 key genes in male brain & testis were obtained based on the network topological parameter betweenness centrality and nodes degree. Among them, cyp19a1b and amh genes in male brain-testis and Tp53 and exo1 genes in female brain-ovary were identified as hub genes having a high level of interaction and expression with other key genes in the network. Further, functional annotation study of these genes revealed their active involvement in important pathways related to reproduction. This is the first report exploring the interaction of brain and gonads in the regulation of magur reproduction through a protein-protein interaction network. The 25 key genes identified in the combined network are involved in various pathways, like neuropeptide signalling pathway, oxytocin receptor-mediated signalling pathway, corticotrophin-releasing factor receptor signalling pathway and reproduction process, which could lead to a better understanding of the magur reproductive system.

Ameliorative effects of nano Moringa on fluoride-induced testicular damage via down regulation of the StAR gene and altered steroid hormones

Fluoride is a common environmental contaminant that has harmful effects on human health when it is present in high concentrations. Fluoride enters the bloodstream after being absorbed by the gastrointestinal system when fluoride-contaminated groundwater is consumed by people. The aim of the present study was to determine whether polyphenol-rich nano Moringa oleifera (NMO) could protect rat testicles from sodium fluoride (NaF) damage by evaluating sperm quality, sex hormones, testicular oxidative status, histopathology, and StAR gene expression. Twenty-eight adult Wistar rats were divided equally and randomly into four groups: group one received distilled water; group two received NMO at a dosage of 250 mg/kg/body weight; group three received NaF at a dosage of 10 mg/kg/body weight; and group four received NaF and NMO. The rats were orally administrated daily for a duration of eight weeks. The study's findings demonstrated that, in comparison to rats exposed to NaF alone, co-administration of NMO and NaF enhanced sperm motility and viability, decreased sperm morphological changes, restored the balance between oxidant and antioxidant status, improved testosterone and dehydroepiandrosterone, improved testicular histology, raised the Johnson score, and upregulated the StAR gene in testicular tissue. These findings show that NMO is promise as a prophylactic medication against sodium fluoride-induced testicular damage because administration of NMO had no adverse effects and enhanced reproductive health.

17β-hydroxysteroid dehydrogenase type 2 activity, expression and cellular localization in abdominal adipose tissues from women

CONTEXT

17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2) may be involved in the local modulation of estradiol (E2) availability in adipose tissues.

OBJECTIVE

To assess the conversion of E2 into estrone (E1) as well as the expression of 17β-HSD2 and its localization in omental (OM) and subcutaneous (SC) adipose tissues obtained from women.

METHODS

Rates of ¹⁴ C-E1 formation from ¹⁴ C-E2 were measured in OM and SC adipose tissue homogenates from 29 women. Specific 17β-HSD2 inhibitor EM-919 was tested in OM and SC adipose tissue homogenates (n = 6). 17β-HSD2 mRNA expression was measured in whole OM and SC adipose tissues (n = 14). Cellular localization of the enzyme was examined using immunohistochemistry. Anthropometric measurements were obtained and body composition as well as body fat distribution were measured.

RESULTS

Significant ¹⁴ C-E1 formation from ¹⁴ C-E2 in OM and SC tissue homogenates was detected. The rate of ¹⁴ C-E1 formation was significantly higher in OM than SC adipose tissue (p < .0001). The conversion of ¹⁴ C-E2 to ¹⁴ C-E1 was significantly inhibited by EM-919 in OM (p < .05) and SC (p < .05) adipose tissues. Significantly higher expression of 17β-HSD2 mRNA in OM versus SC fat was found (p = .03). 17β-HSD2 was localized in the vasculature of OM and SC tissues. Significant negative associations were detected between OM 17β-HSD2 activity and body mass index, WC, lean body mass as well as SC adipose tissue areas.

CONCLUSION

17β-HSD2 converts E2 to E1 in OM and SC adipose tissues of women. The activity of this enzyme decreases with increasing adiposity.

Luteal expression of factors involved in the metabolism and sensitivity to oestrogens in the dog during pregnancy and in non-pregnant cycle

The canine corpus luteum (CL) is the main source of reproductive steroids during dioestrus in the dog and remains active even in the absence of pregnancy (non‐pregnant dioestrus, physiological pseudopregnancy). Whereas the biological effects of 17β‐oestradiol (E2) in the canine CL remain unclear, the transcriptional availability of oestrogen receptors, ESR1 and ESR2, as well as other modulators of local availability of E2, for example, HSD17B7 (converts oestrone into oestradiol), SULT1E1 (inactivates E2 binding capacity to its own receptors through sulphonation) and STS (reverts E2 sulphonation), were previously detected in the CL of non‐pregnant bitches. The aim of the present work was to evaluate the mRNA amounts of these factors involved in luteal sensitivity and metabolism of E2 in the canine CL during the course of non‐pregnant dioestrus (days 10, 20, 30, 40, 50 and 60 post‐ovulation, n = 5/group) and at different stages of pregnancy (n = 4‐6/group): pre‐implantation (days 8–12), post‐implantation (days 18–25), mid‐gestation (days 35–40) and prepartum luteolysis. During pregnancy, the availability of ESR1, HSD17B7, SULT1E1 and STS decreased from mid‐pregnancy to prepartum luteolysis. The main findings during non‐pregnant dioestrus were as follows: increased ESR2:ESR1 ratio on days 40 and 50 after ovulation, decreasing during luteal regression (day 60); increased STS at day 30 when SULT1E1 levels decreased; increased availability of SULT1E1 transcripts during luteal regression; and decreased amounts of HSD17B7 mRNA in early dioestrus, increasing towards later stages. These results suggest that E2 signalling and biologically active local concentrations could diverge in response to time and pregnancy status of the bitch.

Androstenedione (a Natural Steroid and a Drug Supplement): A Comprehensive Review of Its Consumption, Metabolism, Health Effects, and Toxicity with Sex Differences

Androstenedione is a steroidal hormone produced in male and female gonads, as well as in the adrenal glands, and it is known for its key role in the production of estrogen and testosterone. Androstenedione is also sold as an oral supplement, that is being utilized to increase testosterone levels. Simply known as "andro" by athletes, it is commonly touted as a natural alternative to anabolic steroids. By boosting testosterone levels, it is thought to be an enhancer for athletic performance, build body muscles, reduce fats, increase energy, maintain healthy RBCs, and increase sexual performance. Nevertheless, several of these effects are not yet scientifically proven. Though commonly used as a supplement for body building, it is listed among performance-enhancing drugs (PEDs) which is banned by the World Anti-Doping Agency, as well as the International Olympic Committee. This review focuses on the action mechanism behind androstenedione's health effects, and further side effects including clinical features, populations at risk, pharmacokinetics, metabolism, and toxicokinetics. A review of androstenedione regulation in drug doping is also presented.

16-Picolyl-androsterone derivative exhibits potent 17β-HSD3 inhibitory activity, improved metabolic stability and cytotoxic effect on various cancer cells: Synthesis, homology modeling and docking studies

A new androsterone derivative bearing a 16β-picolyl group (compound 5; FCO-586-119) was synthetized in four steps from the lead compound 1 (RM-532-105). We measured its inhibitory activity on 17β-HSD3 using microsomal fraction of rat testes as well as transfected LNCaP[17β-HSD3] cells. We then assessed its metabolic stability as well as its cytotoxic effect against a panel of cancer cell lines. The addition of a picolyl moiety at C-16 of RM-532-105 steroid core improves the 17β-HSD3 inhibitory activity in the microsomal fraction of rat testes, but not in whole LNCaP[17β-HSD3] cells. Interestingly, this structural modification enhances 3-fold the metabolic stability in conjunction with a significant cytotoxic effect against pancreatic, ovarian, breast, lung, and prostate cancer cells. Because the inhibitory activity data against 17β-HSD3 suggested that both steroid derivatives are non-competitive inhibitors, we performed docking and molecular dynamics simulations using a homology model of this membrane-associated enzyme. The results of these simulations revealed that both RM-532-105 (1) and FCO-586-119 (5) can compete for the cofactor-binding site displaying better binding energy than NADP+.

Japanese eel retinol dehydrogenases 11/12-like are 17-ketosteroid reductases involved in sex steroid synthesis

The synthesis of 11-ketotestosterone (11KT) and estradiol-17β (E2), which play important roles in the regulation of gametogenesis in teleost fishes, is catalyzed by several steroidogenic enzymes. In particular, 17β-hydroxysteroid dehydrogenases (Hsd17bs) with 17-ketosteroid reducing activity (17KSR activity) are essential enzymes in the formation of these sex steroid hormones in the gonads and other tissues. Retinol dehydrogenase 11 (RDH11) has been suggested to be a novel tentative HSD17B (HSD17B15) in humans for a decade, however no definitive proof has been provided yet. In this study, three cDNAs related to human RDH11 were isolated from Japanese eel testis and characterized. Sequence similarity and phylogenetic analyses revealed their close relationship to human rdh11 and rdh12 gene products and they were designated as rdh11/12-like 1, rdh11/12-like 2, and rdh11/12-like 3. Three recombinant Rdh11/12-like proteins expressed in HEK293T cells catalyzed the transformation of estrone into E2 and androstenedione into testosterone. Only Rdh11/12-like 1 catalyzed the conversion of 11-ketoandrostenedione into 11KT. Tissue-distribution analysis by quantitative real-time polymerase chain reaction revealed, in immature male Japanese eel, that rdh11/12-like 1 and rdh11/12-like 2 are predominantly expressed in testis and brain, while rdh11/12-like 3 is expressed ubiquitously. Moreover, we analyzed the effects of gonadotropins and 11KT on the expression of the three rdh11/12-like mRNAs in the immature testis. In vitro incubation of immature testes with various doses of recombinant Japanese eel follicle stimulating hormone, luteinizing hormone, and 11KT indicated that the expression of rdh11/12-like 1 mRNA, rdh11/12-like 2, and rdh11/12-like 3 did not change. These findings suggest that the three Rdh11/12-like proteins metabolize sex steroids. Rdh11/12-like 1 may be one of the enzymes with 17KSR activity involved in the production of 11KT in the testis.

Integrative Proteomic and Phosphoproteomic Analyses of Granulosa Cells During Follicular Atresia in Porcine

Ovarian follicular atresia is a natural physiological process; however, the mechanism is not fully understood. In this study, quantitative proteomic and phosphoproteomic analyses of granulosa cells (GCs) in healthy (H), slightly atretic (SA), and atretic follicles (A) of porcine were performed by TMT labeling, enrichment of phosphopeptides, and liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis. In total, 6,201 proteins were quantified, and 4,723 phosphorylation sites of 1,760 proteins were quantified. In total, 24 (11 up, 13 down) and 50 (29 up, 21 down) proteins with a fold change (FC) > 5 were identified in H/SA and H/A, respectively. In addition, there were 20 (H/SA, up) and 39 (H/A, up) phosphosites with an FC > 7 that could serve as potential biomarkers for distinguishing different quality categories of follicles. Western blotting and immunofluorescence confirmed the reliability of the proteomic analysis. Some key proteins (e.g., MIF, beta catenin, integrin β2), phosphosites (e.g., S76 of caspase6, S22 and S636 of lamin A/C), pathways (e.g., apoptosis, regulation of actin cytoskeleton pathway), transcription factors (e.g., STAT5A, FOXO1, and BCLAF1), and kinases (e.g., PBK, CDK5, CDK12, and AKT3) involved in the atresia process were revealed via further analysis of the differentially expressed proteins (DEPs) and phosphorylated proteins (DEPPs). Further study showed that mutant caspase6 Ser76 to Ala increased the ratios of cleaved caspase6/caspase6 and cleaved caspase3/caspase3 and dephosphorylation of caspase6 at Ser76 increased cell apoptotic rate, a new potential pathway of follicular atresia. Collectively, the proteomic and phosphoproteomic profiling and functional research in the current study comprehensively analyzed the dynamic changes in protein expression and phosphorylation during follicular atresia and provided some new explanations regarding the regulation of this process.

Knockdown of CYP19A1 in Buffalo Follicular Granulosa Cells Results in Increased Progesterone Secretion and Promotes Cell Proliferation

Cytochrome P450 aromatase 19A1 (CYP19A1) is a critical enzyme in estrogen synthesis. However, the effect of CYP19A1 on cell growth and hormone secretion of buffalo follicular granulosa cells (BFGCs) is poorly understood. The objective of this study was to assess the role of CYP19A1 in cell proliferation and hormone secretion of BFGCs by knocking down CYP19A1 mRNA expression. The mRNA expression level of CYP19A1 gene was knocked down in BFGCs using the siCYP19A1-296 fragment with the best interference efficiency of 72.63%, as affirmed by real-time quantitative PCR (qPCR) and cell morphology analysis. The CYP19A1 knockdown promoted the proliferation of BFGCs through upregulating the mRNA expression levels of six proliferation-related genes (CCND1, CCNE1, CCNB1, CDK2, CDKN1A, and CDKN1B). Moreover, CYP19A1 knockdown increased (P < 0.05) the concentrations of progesterone secretion (P4) in BFGCs through increasing the mRNA expression levels of three steroidogenic genes (HSD17B1, HSD17B7, and CYP17A1). Our data further found that the FSH could inhibit the mRNA expression level of CYP19A1 in BFGCs, while LH obtains the opposite effect. These findings showed that the CYP19A1 knockdown had a regulatory role in the hormone secretion and cell proliferation in BFGCs.

Transcriptome analysis of Clarias magur brain and gonads suggests neuro-endocrine inhibition of milt release from captive GnRH-induced males

Transcriptome analysis of Clarias magur brain and gonads at preparatory, mature, 6 and 16 h post-GnRH injection (hpi) stages yielded 9.5 GB data with 39,738 contigs. Sequences of 45 reproductive genes were identified for the first time in C. magur along with unique and differentially expressed genes. The expression of 20 genes was validated by qRT-PCR. Upregulation of Cyp11A1, Cyp17A1 and FTZF1 genes in the 16hpi testis accompanied by the 17β-HSD3 expression indicates testosterone (T) synthesis in response to LH surge, while reduced expression of CYP11B1 suggests a high T: 11-KT ratio. It is evident by the gene expression analysis that the inhibitory neurotransmitter GABA, altered T: 11-KT, increased testicular bile acids, and oxytocin-like neuropeptide in the male brain, appear to be involved in arresting the pulsatile motion of testicular smooth muscles. The work generates important leads for an effective induced breeding strategy for silurid catfish.

Core Binding Factors are essential for ovulation, luteinization, and female fertility in mice

Core Binding Factors (CBFs) are a small group of heterodimeric transcription factor complexes composed of DNA binding proteins, RUNXs, and a non-DNA binding protein, CBFB. The LH surge increases the expression of Runx1 and Runx2 in ovulatory follicles, while Cbfb is constitutively expressed. To investigate the physiological significance of CBFs, we generated a conditional mutant mouse model in which granulosa cell expression of Runx2 and Cbfb was deleted by the Esr2Cre. Female Cbfb^flox/flox;Esr2^cre/+;Runx2^flox/flox mice were infertile; follicles developed to the preovulatory follicle stage but failed to ovulate. RNA-seq analysis of mutant mouse ovaries collected at 11 h post-hCG unveiled numerous CBFs-downstream genes that are associated with inflammation, matrix remodeling, wnt signaling, and steroid metabolism. Mutant mice also failed to develop corpora lutea, as evident by the lack of luteal marker gene expression, marked reduction of vascularization, and excessive apoptotic staining in unruptured poorly luteinized follicles, consistent with dramatic reduction of progesterone by 24 h after hCG administration. The present study provides in vivo evidence that CBFs act as essential transcriptional regulators of both ovulation and luteinization by regulating the expression of key genes that are involved in inflammation, matrix remodeling, cell differentiation, vascularization, and steroid metabolisms in mice.

17β-Hydroxysteroid dehydrogenase type 12a responsible for testicular 11-ketotestosterone synthesis in the Japanese eel, Anguilla japonica

The production of 11-ketotestosterone (11KT), an important steroid hormone in piscine spermatogenesis, is regulated by the pituitary gonadotropins [Gths: follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh)] and it is synthesized by catalytic reactions involving several steroidogenic enzymes. Among these enzymes, the role of 17β-hydroxysteroid dehydrogenases (Hsd17bs) that exhibited 17-ketosteroid reducing activity (17KSR activity) responsible for 11KT synthesis is still poorly understood. In the present study, for the deeper understanding of testicular 11KT biosynthesis, we first investigated the steroidogenic pathway to produce 11KT in Japanese eel testis. In vitro incubation of the testis with androstenedione (A4) and the subsequent analysis of the metabolites by thin-layer chromatography indicated that 11KT was synthesized from A4 via 11β-hydroxyandrostenedione (11OHA4) and 11-ketoandrostenedione (11KA4), which indicated that the steroidogenic enzyme exhibiting the 17KSR activity responsible for converting 11KA4 to 11KT is crucial for 11KT production. Subsequently, cDNAs encoding three candidate enzymes, Hsd17b type3 (Hsd17b3), Hsd17b type12a (Hsd17b12a), and 20β-hydroxysteroid dehydrogenase type2 (Hsd20b2), potentially with the 17KSR activity were isolated and characterized in the Japanese eel. The isolated hsd17b3, hsd17b12a, and hsd20b2 cDNAs putatively encoded 308, 314, and 327 amino acid residues with high homology to those of other vertebrate counterparts, respectively. The Hsd17b3, Hsd17b12a, and Hsd20b2 expressed either in HEK293T or in Hepa-E1 converted 11KA4 to 11KT. Tissue-distribution analysis by quantitative real time PCR revealed that hsd17b12a and hsd20b2 mRNAs were detected in the testis, while hsd17b3 mRNA was not detectable. Furthermore, we examined the effects of Gths on the 17KSR activity and the expression of the candidate genes in the immature testis. The 17KSR activity was upregulated by administration of Gths. Furthermore, only expression of hsd17b12a among three candidates was upregulated by Gths as well as the 17KSR activity. These findings strongly suggested that Hsd17b12a is one of the enzymes with 17KSR activity responsible for 11KT synthesis in the testis of Japanese eel.

Role of α-tocopherol and Lactobacillus plantarum in the alleviation of mercuric chloride-induced testicular atrophy in rat's model: Implication of molecular mechanisms

The present work was aimed to evaluate the protective effects of alpha-tocopherol (α-toco) and/or Lactobacillus plantarum (LCB) against testicular atrophy induced by mercuric chloride (MCH). Rats were injected with 5 mg/kg MCH for 5 days consecutively, then treated with 100 mg/kg α-toco and 6 × 10¹⁰ CFU 1.8701/kg LCB alone or together for 3 weeks. The MCH elevated serum TNF-α, IL- 6, caspase-3, and testicular malondialdehyde. However, serum testosterone, dehydroepiandrosterone, testicular messenger RNA of a steroidogenic acute regulatory protein, 17-β-hydroxysteroid dehydrogenase, 3β-hydroxysteroid dehydrogenase, glutathione level, and superoxide dismutase activity were decreased. Protein expression of Nrf2 was downregulated whereas that of Bax and DNA fragmentation was upregulated in the testicular tissues. Treatment with α-toco and LCB ameliorated the deviated biochemical parameters and improved tissue injury. It was concluded that the combination of LCB and α-toco achieved promising results in the amelioration of MCH-induced testicular atrophy. Nrf2, Bax expressions, and DNA fragmentation are involved in the testicular atrophy induced by MCH.

Evaluating the effects on steroidogenesis of estragole and trans-anethole in a feto-placental co-culture model

In this study, we determined whether estragole and its isomer trans-anethole interfered with feto-placental steroidogenesis in a human co-culture model composed of fetal-like adrenocortical (H295R) and placental trophoblast-like (BeWo) cells. Estragole and trans-anethole are considered the biologically active compounds within basil and fennel seed essential oils, respectively. After a 24 h exposure of the co-culture to 2.5, 5.2 and 25 μM estragole or trans-anethole, hormone concentrations of estradiol, estrone, dehydroepiandrosterone, androstenedione, progesterone and estriol were significantly increased. Using RT-qPCR, estragole and trans-anethole were shown to significantly alter the expression of several key steroidogenic enzymes, such as those involved in cholesterol transport and steroid hormone biosynthesis, including StAR, CYP11A1, HSD3B1/2, SULT2A1, and HSD17B1, -4, and -5. Furthermore, we provided mechanistic insight into the ability of estragole and trans-anethole to stimulate promoter-specific expression of CYP19 through activation of the PKA pathway in H295R cells and the PKC pathway in BeWo cells, in both cases associated with increased cAMP levels. Moreover, we show new evidence suggesting a role for progesterone in regulating steroid hormone biosynthesis through regulation of the StAR gene.

Functional genomic studies reveal the androgen receptor as a master regulator of cellular energy metabolism in prostate cancer

Sex-steroid hormones have been investigated for decades for their oncogenic properties in hormone-dependent cancers. The increasing body of knowledge on the biological actions of androgens in prostate cancer has led to the development of several targeted therapies that still represent the standard of care for cancer patients to this day. In the prostate, androgens promote cellular differentiation and proper tissue development. These hormones also promote the aberrant proliferation and survival of prostate cancer cells. Over the past few years, sequencing technologies for functional genomic analyses have rapidly expanded, revealing novel functions of sex-steroid hormone receptors other than their classic roles. In this article, we will focus on transcriptomic- and genomic-based evidence that demonstrates the importance of the androgen receptor signaling in the regulation of prostate cancer cell metabolism. This is significant because the reprogramming of cell metabolism is a hallmark of cancer. In fact, it is clear now that the androgen receptor contributes to the reprogramming of specific cellular metabolic pathways that promote tumor growth and disease progression, including aerobic glycolysis, mitochondrial respiration, fatty acid ß-oxidation, and de novo lipid synthesis. Overall, beyond regulating development, differentiation, and proliferation, the androgen receptor is also a master regulator of cellular energy metabolism.

17B-hydroxysteroid dehydrogenases as acyl thioester metabolizing enzymes

17β-Hydroxysteroid dehydrogenases (HSD17B) catalyze the oxidation/reduction of 17β-hydroxy/keto group in position C17 in C18- and C19 steroids. Most HSD17Bs are also catalytically active with substrates other than steroids. A subset of these enzymes is able to process thioesters of carboxylic acids. This group of enzymes includes HSD17B4, HSD17B8, HSD17B10 and HSD17B12, which execute reactions in intermediary metabolism, participating in peroxisomal β-oxidation of fatty acids, mitochondrial oxidation of 3R-hydroxyacyl-groups, breakdown of isoleucine and fatty acid chain elongation in endoplasmic reticulum. Divergent substrate acceptance capabilities exemplify acquirement of catalytic site adaptiveness during evolution. As an additional common feature these HSD17Bs are multifunctional enzymes that arose either via gene fusions (HSD17B4) or are incorporated as subunits into multifunctional protein complexes (HSD17B8 and HSD17B10). Crystal structures of HSD17B4, HSD17B8 and HSD17B10 give insight into their structure-function relationships. Thus far, deficiencies of HSD17B4 and HSD17B10 have been assigned to inborn errors in humans, underlining their significance as enzymes of metabolism.

Molecular identification of steroidogenesis-related genes in scallops and their potential roles in gametogenesis

Sex steroids are crucial for controlling gametogenesis and germ cell maturation in vertebrates. It has been proposed that Yesso scallop (Mizuhopecten yessoensis) has the same sex steroids as those animals, but the scallop biosynthetic pathway is unclear. In this study, we characterized several steroidogenesis-related genes in M. yessoensis and proposed a putative biosynthetic pathway for sex steroids that is similar to that of vertebrates. Specifically, we identified several steroidogenesis-related gene sequences that encode steroid metabolizing enzymes: StAR-related lipid transfer (START) protein, 17α-hydroxylase, 17,20-lyase (cyp17a), 17β-hydroxysteroid dehydrogenase (hsd17b), and 3β-hydroxysteroid dehydrogenase (hsd3b). We sampled adult scallops throughout their reproductive phase to compare their degree of maturation with their intensity of mRNA expression. Semi-quantitative RT-PCR analysis revealed a ubiquitous expression of transcripts for steroid metabolizing enzymes (i.e., star, cyp17a, hsd17b, and hsd3b) in peripheral and gonadal tissues. Real-time PCR analysis revealed a high level of expression of star3 and cyp17a genes in gonadal tissues at the early stage of cell differentiation in scallops. Interestingly, mRNA expression of hsd3b and hsd17b genes showed a synchronous pattern related to degree of gonad maturity. These results indicate that both hsd3b and hsd17b genes are likely involved in steroidogenesis in scallops. We therefore believe that these steroid-metabolizing enzymes allow scallops to endogenously produce sex steroids to regulate reproductive events.

Molecular characterization and expression profiling of 17-beta-hydroxysteroid dehydrogenase 2 and spermatogenesis associated protein 2 genes in endangered catfish, Clarias magur (Hamilton, 1822)

The 17-beta-hydroxysteroid dehydrogenase 2 (17β-HSD2) enzyme regulates steroid levels by the inactivation of estrogen and androgens. Spermatogenesis associated protein 2 (SPATA2) plays a vital role in spermatogenesis in vertebrates including fish. We report cloning and characterization of full cds of 17β-HSD2 and SPATA2 genes in Clarias magur. The full-length cDNA sequences of 17β-HSD2 and SPATA2 were 1187 bp (ORF 1125 bp) and 1806 bp (ORF 1524 bp) encoding 375 and 508 amino acids, respectively. Signal peptide analysis revealed SPATA2 is nonsecretory, while 17β-HSD2 is a secretory protein. Hydropathy profiles showed both proteins are hydrophilic in nature. Tissue distribution of both the genes revealed high mRNA level of SPATA2 in all tissues examined indicating its wide range of expression. 17β-HSD2 indicated higher expression in preparatory phase compared to spawning phase in ovary while it was opposite in case of testis. SPATA2 showed significantly higher expression in preparatory phase compared to spawning phase in both ovary and testis. Administration of Ovatide^TM (GnRH analog) resulted in upregulation of SPATA2 expression at 6 and 16 h post-injection while 17β-HSD2 showed upregulation only at 6 h post-injection. To the best of our knowledge, this is a first report on characterization of 17β-HSD2 and SPATA2 full-length cDNA in catfish.

The effects and possible mechanisms of triclosan on steroidogenesis in primary rat granulosa cells

BACKGROUND

Triclosan (TCS) has been detected in human tissues. It can disrupt steroidogenesis in vivo. The study on the effects of TCS on ovarian granulosa cells was lacking.

METHODS

Primary rat granulosa cells (rGCs) were treated with TCS. Concentrations of estradiol (E₂), progesterone (P₄) in the cell culture supernatants were measured. Microarray was used to measure gene expression profiles. Pathway analysis was performed to identify signaling networks that linked differentially expressed genes (DEGs). Genes related with steroidogenesis were analyzed.

RESULTS

TCS increased E₂ and P₄ production. A total of 2006 DEGs were identified. Pathway analysis revealed that ovarian steroidogenesis pathway was upregulated. Both PCR and Western-blot demonstrated that the expressions of key genes involved in this pathway were significantly increased.

CONCLUSIONS

TCS co-administered with follicle-stimulating hormone (FSH) could increase E₂ and P₄ production in rGCs and up-regulate ovarian steroidogenesis pathway. StAR and aromatase protein were increased by TCS, while P450scc protein wasn't changed significantly.

Pattern of aromatase mRNA expression in the brain of a weakly electric fish, Apteronotus leptorhynchus

Aromatase is a steroidogenic enzyme involved in the conversion of testosterone into estradiol. Teleosts are unique among vertebrates in possessing two distinct aromatase genes that show different expression patterns within the body. Since the brain is the essential organ underlying the control of behavior, an understanding of the expression pattern of aromatase in the brain can help to identify neural circuits and behaviors that are most likely to be affected by aromatase activity. In addition, identifying species differences in aromatase expression in the brain can further our understanding of divergence in behaviors regulated by local estradiol production and estrogen signaling. Apteronotus leptorhynchus is a species of weakly electric fish in which little is known about sex steroid expression within the brain and its role in electric signaling behavior. The goal of this study was to identify the mRNA expression pattern of aromatase in the brain of A. leptorhynchus. Aromatase mRNA was detected in several parts of the forebrain and in the pituitary gland; however, no aromatase expression was detected in the midbrain or hindbrain. These findings in A. leptorhynchus support a role for aromatase activity in reproduction, but no direct role in electric signaling behavior in non-breeding fish. The findings of this study help to broaden the basis for making phylogenetic comparisons of aromatase expression across teleost lineages as well as different signaling systems, and provide information on behaviors and neural circuits that are potentially affected by local estradiol production in A. leptorhynchus.

17β-Hydroxysteroid dehydrogenase 3 deficiency: Three case reports and a systematic review

17β-Hydroxysteroid dehydrogenase 3 deficiency is a rare autosomal recessive cause of 46, XY disorders of sex development resulting from HSD17B3 gene mutations, however, no case has been reported in East Asia. The aim of this study was to report three Chinese 46, XY females with 17β-HSD3 deficiency in a single center and perform a systematic review of the literature. Clinical examination, endocrine evaluation and HSD17B3 gene sequencing were performed in the three Chinese phenotypically females (two sisters and one unrelated patient). Relevant articles were searched by using the term "HSD17B3" OR "17beta-HSD3 gene" with restrictions on language (English) and species (human) in Pubmed and Embase. All the three phenotypically female subjects showed 46, XY karyotype, inguinal masses, decreased testosterone and increased androstenedione. Two novel homozygous mutations (W284X and c.124_127delTCTT) in HSD17B3 gene were identified. A systematic review found a total of 121 pedigrees/158 patients, with 78.5% (124/158) of patients assigned as females, 15.2% (24/158) from females to males, and 5.1% (8/158) raised as males. The most common mutation was c.277+4C>T (allele frequency: 25/72) for patients from Europe, and R80Q (allele frequency: 21/54) for patients from West Asia. The testicular histology showed normal infantile testicular tissue in 100% (9/9) infantile patients, normal quantity germ cells in 44.4% (8/18) prepubertal patients and 19.0% (4/21) pubertal and adult patients. We reported the first East Asian 17β-hydroxysteroid dehydrogenase 3 deficiency cases. Additional literature reviews found founder effects among patients with different ethnic background and early orchiopexy may benefit fertility in patients assigned as males. These findings may significantly expand the clinical, ethnic and genetic spectrum of 17β-hydroxysteroid dehydrogenase 3 deficiency.

Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGFA) synergistically promote steroidogenesis and survival of cultured buffalo granulosa cells

The present study investigated the combined effect of fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor A (VEGF-A) on estradiol (E₂) secretion and relative abundance of mRNA for aromatase enzyme (CYP19A1), proliferating cell nuclear antigen (PCNA) and BCL-2 associated X protein (BAX) in cultured buffalo granulosa cells (GCs). Follicles were isolated and classified into four groups based on size and E₂ concentration in follicular fluid (FF): Small, 4-6mm diameter, E₂<0.5ng/ml; Medium, 7-9mm, E₂=0.5-5ng/ml; Large, 10-13mm, E₂=5-40ng/ml; Preovulatory (PFs), >14mm, E₂>180ng/ml. The GCs of PF were cultured in 24 well cell culture plates and allowed to become 75-80% confluent. Then cultured GCs were treated with FGF2 (200ng/ml) and VEGF-A (100ng/ml) separately and in combination for three incubation periods (24, 48 and 72h). Estradiol secretion was greater in GCs treated with FGF2+VEGF-A compared to FGF2 or VEGF-A at all incubation periods and was greatest (P<0.05) at 72h of incubation. The relative abundance of CYP19A1 and PCNA mRNA were relatively consistent with the amount E₂ secretion. In contrast, the relative abundance of Bax mRNA was less in GCs treated with the combination of FGF2 and VEGF-A as compared to either FGF2 or VEGF-A alone and the least concentration (P<0.05) was at 72h of incubation. Findings with use of immunocytochemistry of cells treated with these factors were consistent to the relative abundance of mRNA transcript for the factor. The present findings indicate that FGF2 and VEGF-A may function in a synergistic manner to promote steroidogenesis and survival of cultured buffalo GCs.

Intracrine Control of Estrogen Action in Human Gestational Tissues at Parturition

OBJECTIVE

We examined whether estrogen action in human parturition is regulated by an intracrine mechanism mediated by target tissue expression of specific 17beta-hydroxysteroid dehydrogenase (17betaHSD) isozymes that interconvert estrone (E1) and estradiol (E2), such that the onset of labor is associated with an increase in local E2 bioavailability.

METHODS

The extent of 17betaHSD-1, -2, -3, -4, -5, and -7 expression (measured by quantitative reverse transcriptase polymerase chain reaction) and the capacity to interconvert E1 and E2 were compared in amnion, chorion, placenta, decidua, and myometrium obtained from women at term before (n = 6) and after (n = 6) the onset of labor.

RESULTS

In chorion, abundance of 17betaHSD-1 (converts E1 to E2) mRNA decreased 2.7-fold (P <.05) in association with labor onset. In myometrium, 17betaHSD-1 and 17betaHSD-4 (converts E2 to E1) mRNAs increased two-fold and five-fold, respectively, with the onset of labor (P <.05 for each). No other statistically significant labor-associated change in 17betaHSD expression was observed. In chorion, 17betaHSD oxidative (E2 to E1) and reductive (E1 to E2) activities and the net E2 synthetic capacity increased with labor. In decidua, both activities decreased with the onset of labor, but there was no change in net E2 synthetic capacity. The capacity to interconvert E1 and E2 did not change in the other tissues.

CONCLUSION

The increase in E2 synthetic capacity in the chorion might contribute to an increase in local estrogen bioactivity in association with the onset of labor. However, it cannot be explained by changes in 17betaHSD isozyme expression and is unlikely to account for the increased estrogen action at parturition. These data show that intracrine mechanisms based on 17betaHSD isozyme expression play a minor role, if any, in controlling estrogen action in gestational tissues during human parturition.

Mimicking postmenopausal steroid metabolism in breast cancer cell culture: Differences in response to DHEA or other steroids as hormone sources

Following menopause virtually 100% of estrogens are synthesized in peripheral target tissues from precursor steroids of adrenal origin. These steroids are the unique source of sex steroids in these women. This positions some steroid metabolizing enzymes as primary targets for novel therapies for estrogen receptor-positive (ER+) breast cancer. However, previous research on the steroid-converting enzymes has been performed using their direct substrate as a hormone source, depending on the facility where studied and the robust signal obtained. These experiments may not always provide an accurate reflection of physiological and post-menopausal conditions. We suggest providing dehydroepiandrosterone (DHEA) as an intracrinological hormone source, and comparing the role of steroid-converting enzymes using DHEA and their direct substrates when an extensive mechanistic understanding is required. Here, we present a comparative study of these enzymes with the provision of DHEA and the direct substrates, estrone (E1) or dihydrotestosterone (DHT), or additional steroids as hormone sources, in breast cancer cells. Enzyme knockdown by respective specific siRNAs and observations on the resulting differences in biological function were carried out. Cell biology studies showed no difference in biological function for 17β-HSD1 and 17β-HSD7 when cultured with different steroid hormones: cell proliferation and estradiol levels decreased, whereas DHT accumulated; cyclinD1, PCNA, and pS2 were down-regulated after knocking down these two enzymes, although the quantitative results varied. However, culture medium supplementation was found to have a marked impact on the study of 3α-HSD3. We demonstrated that provision of different steroids as a substrate or hormone sources may promote modified biological effects: provision of DHEA is the preferred choice to mimic postmenopausal steroid metabolism in cell culture.

The effects of the standardized extracts of Ginkgo biloba on steroidogenesis pathways and aromatase activity in H295R human adrenocortical carcinoma cells

OBJECTIVES

Aromatase inhibitors that block estrogen synthesis are a proven first-line hormonal therapy for postmenopausal breast cancer. Although it is known that standardized extract of Ginkgo biloba (EGb761) induces anti-carcinogenic effects like the aromatase inhibitors, the effects of EGb761 on steroidogenesis have not been studied yet. Therefore, the effects of EGb761 on steroidogenesis and aromatase activity was studied using a H295R cell model, which was a good in vitro model to predict effects on human adrenal steroidogenesis.

METHODS

Cortisol, aldosterone, testosterone, and 17β-estradiol were evaluated in the H295R cells by competitive enzyme-linked immunospecific assay after exposure to EGb761. Real-time polymerase chain reaction were performed to evaluate effects on critical genes in steroid hormone production, specifically cytochrome P450 (CYP11/ 17/19/21) and the hydroxysteroid dehydrogenases (3β-HSD2 and 17β-HSD1/4). Finally, aromatase activities were measured with a tritiated water-release assay and by western blotting analysis.

RESULTS

H295R cells exposed to EGb761 (10 and 100 μg/mL) showed a significant decrease in 17β-estradiol and testosterone, but no change in aldosterone or cortisol. Genes (CYP19 and 17β-HSD1) related to the estrogen steroidogenesis were significantly decreased by EGb761. EGb761 treatment of H295R cells resulted in a significant decrease of aromatase activity as measured by the direct and indirect assays. The coding sequence/ Exon PII of CYP19 gene transcript and protein level of CYP19 were significantly decreased by EGb761.

CONCLUSIONS

These results suggest that EGb761 could regulate steroidogenesis-related genes such as CYP19 and 17β-HSD1, and lead to a decrease in 17β-estradiol and testosterone. The present study provides good information on potential therapeutic effects of EGb761 on estrogen dependent breast cancer.

Type 2 17-β hydroxysteroid dehydrogenase as a novel target for the treatment of osteoporosis

Low estradiol level in postmenopausal women is implicated in osteoporosis, which occurs because of the high bone resorption rate. Estrogen formation is controlled by 17-β hydroxysteroid dehydrogenase 17-β HSD enzymes, where 17-β HSD type 1 contributes in the formation of estradiol, while type 2 catalyzes its catabolism. Inhibiting 17-β HSD2 can help in increasing estradiol concentration. Several promising 17-β HSD2 inhibitors that can act at low nanomolar range have been identified. However, there are some specific challenges associated with the application of these compounds. Our review provides an up-to-date summary of the current status and recent progress in the production of 17-β HSD2 inhibitors as well as the future challenges in their clinical application.

Synthesis of a dansyl-labeled inhibitor of 17β-hydroxysteroid dehydrogenase type 3 for optical imaging

The steroidogenic enzyme 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) is a therapeutic target in the management of androgen-sensitive diseases such as prostate cancer and benign prostate hyperplasia. In this Letter, we designed and synthesized the first fluorescent inhibitor of this enzyme by combining a fluorogenic dansyl moiety to the chemical structure of a known inhibitor of 17β-HSD3. The synthesized compound 3 is a potent fluorogenic compound (λex=348 nm and λ em=498 nm). It crosses the cell membrane, keeps its fluorescent properties and is distributed inside the LNCaP cells overexpressing 17β-HSD3, where it inhibits the transformation of 4-androstene-3,17-dione into the androgen testosterone (IC50=262 nM).

Biochemical analyses and molecular modeling explain the functional loss of 17β-hydroxysteroid dehydrogenase 3 mutant G133R in three Tunisian patients with 46, XY Disorders of Sex Development

Mutations in the HSD17B3 gene resulting in 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) deficiency cause 46, XY Disorders of Sex Development (46, XY DSD). Approximately 40 different mutations in HSD17B3 have been reported; only few mutant enzymes have been mechanistically investigated. Here, we report novel compound heterozygous mutations in HSD17B3, composed of the nonsense mutation C206X and the missense mutation G133R, in three Tunisian patients from two non-consanguineous families. Mutants C206X and G133R were constructed by site-directed mutagenesis and expressed in HEK-293 cells. The truncated C206X enzyme, lacking part of the substrate binding pocket, was moderately expressed and completely lost its enzymatic activity. Wild-type 17β-HSD3 and mutant G133R showed comparable expression levels and intracellular localization. The conversion of Δ4-androstene-3,17-dione (androstenedione) to testosterone was almost completely abolished for mutant G133R compared with wild-type 17β-HSD3. To obtain further mechanistic insight, G133 was mutated to alanine, phenylalanine and glutamine. G133Q and G133F were almost completely inactive, whereas G133A displayed about 70% of wild-type activity. Sequence analysis revealed that G133 on 17β-HSD3 is located in a motif highly conserved in 17β-HSDs and other short-chain dehydrogenase/reductase (SDR) enzymes. A homology model of 17β-HSD3 predicted that arginine or any other bulky residue at position 133 causes steric hindrance of cofactor NADPH binding, whereas substrate binding seems to be unaffected. The results indicate an essential role of G133 in the arrangement of the cofactor binding pocket, thus explaining the loss-of-function of 17β-HSD3 mutant G133R in the patients investigated.

Oxidative activity of 17β-hydroxysteroid dehydrogenase on testosterone in male abdominal adipose tissues and cellular localization of 17β-HSD type 2

Testosterone can be converted into androstenedione (4-dione) by 17β-hydroxysteroid dehydrogenase (HSD) activity likely performed by 17β-HSD type 2. Our objective was to evaluate the rate of testosterone conversion to 4-dione as well as expression and localization of 17β-HSD type 2 in omental (OM) vs. subcutaneous (SC) adipose tissues of men. Formation of 4-dione from testosterone was significantly higher in homogenates (p ≤ 0.001) and explants (p ≤ 0.01) of OM than SC tissue. Microscopy analyses and biochemical assays in cell fractions localized the enzyme in the vasculature/endothelial cells of adipose tissues. Conversion of testosterone to 4-dione was weakly detected in most OM and/or SC preadipocyte cultures. Positive correlations were found between 17β-HSD type 2 activity in whole tissue and BMI or SC adipocyte diameter. We conclude that conversion of testosterone to 4-dione detected in abdominal adipose tissue is caused by 17β-HSD type 2 which is localized in the vasculature of the adipose compartment.

Updated survey of the steroid-converting enzymes in human adipose tissues

Over the past decade, adipose tissues have been increasingly known for their endocrine properties, that is, their ability to secrete a number of adipocytokines that may exert local and/or systemic effects. In addition, adipose tissues have long been recognized as significant sites for steroid hormone transformation and action. We hereby provide an updated survey of the many steroid-converting enzymes that may be detected in human adipose tissues, their activities and potential roles. In addition to the now well-established role of aromatase and 11β-hydroxysteroid dehydrogenase (HSD) type 1, many enzymes have been reported in adipocyte cell lines, isolated mature cells and/or preadipocytes. These include 11β-HSD type 2, 17β-HSDs, 3β-HSD, 5α-reductases, sulfatases and glucuronosyltransferases. Some of these enzymes are postulated to bear relevance for adipose tissue physiology and perhaps for the pathophysiology of obesity. This elaborate set of steroid-converting enzymes in the cell types of adipose tissue deserves further scientific attention. Our work on 20α-HSD (AKR1C1), 3α-HSD type 3 (AKR1C2) and 17β-HSD type 5 (AKR1C3) allowed us to clarify the relevance of these enzymes for some aspects of adipose tissue function. For example, down-regulation of AKR1C2 expression in preadipocytes seems to potentiate the inhibitory action of dihydrotestosterone on adipogenesis in this model. Many additional studies are warranted to assess the impact of intra-adipose steroid hormone conversions on adipose tissue functions and chronic conditions such as obesity, diabetes and cancer.

Expression of 17β-hydroxysteroid dehydrogenase type 2 is associated with some clinicopathological features in gastric cancer

In most populations, gastric cancer (GC) incidence is higher in men than in women, which may suggest the role of sex steroid hormones in gastric cancerogenesis. Both, androgens and estrogens can be synthetised in peripherial tissues. This process is controlled by expression of steroidogenic enzymes. Therefore, we evaluate the 17β-hydroxysteroid dehydrogenase type 2 (HSD17B2) transcript and protein levels in gastric tumoral and nontumoral tissue. We also determined the association between HSD17B2 transcript and protein levels and some clinicopathological features in GC. We found significantly decreased levels of HSD17B2 transcript (P=0.00072) and protein (P=0.00017) in primary tumoral tissues of GC patients, as compared to nontumoral tissues. In patients above 60 years of age the amounts of HSD17B2 transcript (P=0.00044) and protein (P=0.00027) were significantly lower in tumoral than nontumoral tissues. Similarly, lower HSD17B2 levels, both in terms of the transcript and protein, were observed in tumoral tissues of male (P=0.013, P=0.0014), patients stomach (P=0.0062, P=0.045) and cardia (P=0.02, P=0.02) site of tumor, T3 (P=0.018, P=0.014) depth of invasion, N0 (P=0.017, P=0.045) lymph node metastasis, G3 (P=0.0027, P=0.014) malignancy grade. We also observed significantly reduced level of HSD17B2 transcript in tumoral tissue specimens of females (P=0.014), T4 depth of invasion (P=0.02), N3 lymph node metastasis (P=0.037) and G2 malignancy grade (P=0.045). Furthermore, diffuse GC histological types were associated with lower HSD17B2 protein level (P=0.024) than nontumoral tissues. We demonstrated that HSD17B2 transcript and protein levels are linked to some clinicopathological features in GC.

Expression and localization of ghrelin and its receptor in ovarian follicles during different stages of development and the modulatory effect of ghrelin on granulosa cells function in buffalo

Ghrelin, a hormone predominantly found in the stomach, was recently described as a factor that controls female reproductive function. The aim of our study was to investigate the expression and localization of ghrelin and its active receptor, growth hormone secretagogue receptor type 1a (GHS-R1a) in buffalo ovarian follicles of different follicular size and to investigate role of ghrelin on estradiol (E2) secretion, aromatase (CYP19A1), proliferating cell nuclear antigen (PCNA) and apoptosis regulator Bax gene expression on granulosa cell culture. Using real time PCR and western blot, we measured gene and protein expression of examined factors. Localization was done with immunofluorescence method. Expression of ghrelin increased with follicle size with significantly highest in dominant or pre-ovulatory follicle (P<0.05). Expression of GHS-R1a was comparable in medium and large follicle but was higher than small follicles (P<0.05). Both the factors were localized in granulosa and theca cells. Pattern of intensity of immunofluorescence was similar with mRNA and protein expression. In the in vitro study granulosa cells (GCs) were cultured and treated with ghrelin each at 1, 10 and 100ng/ml concentrations for two days after obtaining 75-80 per cent confluence. Ghrelin treatment significantly (P<0.05) inhibited E2 secretion, CYP19A1 expression, apoptosis and promoted cell proliferation. In conclusion, this study provides novel evidence for the presence of ghrelin and receptor GHS-R1a in ovarian follilcles and modulatory role of ghrelin on granulosa cell function in buffalo.

Genetic variation in estrogen and progesterone pathway genes and breast cancer risk: an exploration of tumor subtype-specific effects

PURPOSE

To determine whether associations between estrogen pathway-related single nucleotide polymorphisms (SNPs) and breast cancer risk differ by molecular subtype, we evaluated associations between SNPs in cytochrome P450 family 19 subfamily A polypeptide 1 (CYP19A1), estrogen receptor (ESR1), 3-beta hydroxysteroid dehydrogenase type I (HSD3B1), 17-beta hydroxysteroid dehydrogenase type II (HSD17B2), progesterone receptor (PGR), and sex hormone-binding globulin (SHBG) and breast cancer risk in a case-control study in North Carolina.

METHODS

Cases (n = 1,972) were women 20-74 years old and diagnosed with breast cancer between 1993 and 2001. Population-based controls (n = 1,776) were frequency matched to cases by age and race. A total of 195 SNPs were genotyped, and linkage disequilibrium was evaluated using the r (2) statistic. Odds ratios (ORs) and 95 % confidence intervals (CIs) for associations with breast cancer overall and by molecular subtype were estimated using logistic regression. Monte Carlo methods were used to control for multiple comparisons; two-sided p values <3.3 × 10(-4) were statistically significant. Heterogeneity tests comparing the two most common subtypes, luminal A (n = 679) and basal-like (n = 200), were based on the Wald statistic.

RESULTS

ESR1 rs6914211 (AA vs. AT+TT, OR 2.24, 95 % CI 1.51-3.33), ESR1 rs985191 (CC vs. AA, OR 2.11, 95 % CI 1.43-3.13), and PGR rs1824128 (TT+GT vs. GG, OR 1.33, 95 % CI 1.14-1.55) were associated with risk after accounting for multiple comparisons. Rs6914211 and rs985191 were in strong linkage disequilibrium among controls (African-Americans r (2) = 0.70; whites r (2) = 0.95). There was no evidence of heterogeneity between luminal A and basal-like subtypes, and the three SNPs were also associated with elevated risk of the less common luminal B, HER2+/ER-, and unclassified subtypes.

CONCLUSIONS

ESR1 and PGR SNPs were associated with risk, but lack of heterogeneity between subtypes suggests variants in hormone-related genes may play similar roles in the etiology of breast cancer molecular subtypes.

Cloning, characterization and functional expression of Taenia solium 17 beta-hydroxysteroid dehydrogenase

The 17β-hydroxysteroid dehydrogenases (17β-HSD) are key enzymes involved in the formation (reduction) and inactivation (oxidation) of sex steroids. Several types have been found in vertebrates including fish, as well as in invertebrates like Caenorhabditis elegans, Ciona intestinalis and Haliotis diversicolor supertexta. To date limited information is available about this enzyme in parasites. We showed previously that Taenia solium cysticerci are able to synthesize sex steroid hormones in vitro when precursors are provided in the culture medium. Here, we identified a T. solium 17β-HSD through in silico blast searches in the T. solium genome database. This coding sequence was amplified by RT-PCR and cloned into the pcDNA 3.1(+) expression vector. The full length cDNA contains 957bp, corresponding to an open reading frame coding for 319 aa. The highest identity (84%) at the protein level was found with the Echinococcus multilocularis 17β-HSD although significant similarities were also found with other invertebrate and vertebrate 17β-HSD sequences. The T. solium Tsol-17βHSD belongs to the short-chain dehydrogenase/reductase (SDR) protein superfamily. HEK293T cells transiently transfected with Tsol17β-HSD induced expression of Tsol17β-HSD that transformed 3H-androstenedione into testosterone. In contrast, 3H-estrone was not significantly transformed into estradiol. In conclusion, T. solium cysticerci express a 17β-HSD that catalyzes the androgen reduction. The enzyme belongs to the short chain dehydrogenases/reductase family and shares motifs and activity with the type 3 enzyme of some other species.

46,XY disorder of sex development in a sudanese patient caused by a novel mutation in the HSD17B3 gene

In this study, we present a Sudanese 46,XY patient raised as a female and diagnosed at the age of 20 years with having 17β-hydroxysteroid dehydrogenase type 3 (17β-HSD3) deficiency. She presented with primary amenorrhea, undeveloped breasts and a male pattern of secondary sexual characteristics. Examination of her external genitalia showed type IV genital circumcision. Steroid measurements both in urine and serum pointed to 17β-HSD3 deficiency. A novel homozygous splice-site mutation [c.524 + 2T>A] was detected in intron 7 of the HSD17B3 gene. In this patient, steroid concentration clearly supported both the clinical diagnosis of 17β-HSD3 deficiency and the functional relevance of the mutation. Interestingly, despite of the type IV genital circumcision, the patient expressed her interest in reassigning her sex from female to male.

Characteristics of 17β-hydroxysteroid dehydrogenase 8 and its potential role in gonad of Zhikong scallop Chlamys farreri

17β-Hydroxysteroid dehydrogenases (17β-HSDs) are important enzymes catalyzing steroids biosynthesis and metabolism in vertebrates. Although studies indicate steroids play a potential role in reproduction of molluscs, little is known about the presence and function of 17β-HSDs in molluscs. In the present study, a full-length cDNA encoding 17β-HSD type 8 (17β-HSD8) was identified in the Zhikong scallop Chlamys farreri, which is 1104bp in length with an open reading frame of 759bp encoding a protein of 252 amino acids. Phylogenetic analysis revealed that the C. farreri 17β-HSD8 (Cf-17β-HSD8) belongs to the short chain dehydrogenase/reductase family (SDR) and shares high homology with other 17β-HSD8 homologues. Catalytic activity assay in vitro demonstrated that the refolded Cf-17β-HSD8 expressed in Escherichia coli could effectively convert estradiol-17β (E2) to estrone (E1), and weakly catalyze the conversion of testosterone (T) to androstenedione (A) in the presence of NAD(+). The Cf-17β-HSD8 mRNA was ubiquitously expressed in all tissues analyzed, including gonads. The expression levels of Cf-17β-HSD8 mRNA and protein increased with gametogenesis in both ovary and testis, and were significantly higher in testis than in ovary at growing stage and mature stage. Moreover, results of in situ hybridization and immunohistochemistry revealed that the mRNA and protein of Cf-17β-HSD8 were expressed in follicle cells and gametes at all stages except spermatozoa. Our findings suggest that Cf-17β-HSD8 may play an important role in regulating gametogenesis through modulating E2 levels in gonad of C. farreri.

Differential effects of yolk testosterone and androstenedione in embryo development and nestling growth in the spotless starling (Sturnus unicolor)

Yolk androgens in avian eggs play a significant role in embryo and nestling development. However, few studies have examined the differential effect of two of the main yolk androgens, testosterone (T) and androstenedione (A4). Here, we injected eggs of spotless starlings with physiological levels of either T, A4, the combination T+A4 or vehicle substance (control), to examine the differential ability of these steroids to influence nestling development. We found that the duration of the embryonic period was increased by T, and less so by A4, but not by the combination T+A4. Body condition was reduced in all experimental treatments where A4 was present, particularly so in the combination T+A4. Tarsus length was increased in males by A4, and in a lower degree by T, whereas the combination T+A4 inhibited growth. However, these differences in tarsus length between groups disappeared at the end of the nestling period. Cell-mediated immune responsiveness was marginally affected by the interaction between treatment and sex. These patterns suggest that in this species, T has a stronger influence during embryo development than A4, whereas during nestling development the capacities of both androgens to influence growth are similar. The combination T+A4 showed non-additive effects, suggesting either some kind of inhibition between the two androgens, or else an excessive effect due to a bell-shaped pattern of response. Our results suggest a complex picture of sex and age-dependent effects of T and A4, and underline the necessity of further research in the metabolism and action of egg androgens.

Current status on development of steroids as anticancer agents

Steroids are important biodynamic agents. Their affinities for various nuclear receptors have been an interesting feature to utilize them for drug development particularly for receptor mediated diseases. Steroid biochemistry and its crucial role in human physiology, has attained importance among the researchers. Recent years have seen an extensive focus on modification of steroids. The rational modifications of perhydrocyclopentanophenanthrene nucleus of steroids have yielded several important anticancer lead molecules. Exemestane, SR16157, fulvestrant and 2-methoxyestradiol are some of the successful leads emerged on steroidal pharmacophores. The present review is an update on some of the steroidal leads obtained during past 25 years. Various steroid based enzyme inhibitors, antiestrogens, cytotoxic conjugates and steroidal cytotoxic molecules of natural as well as synthetic origin have been highlighted. This article is part of a Special Issue entitled "Synthesis and biological testing of steroid derivatives as inhibitors".

Expression of 17β-hydroxysteroid dehydrogenase type 1 in gastric cancer

There are several findings suggesting the protective role of estrogens in gastric carcinogenesis. Extragonadal 17β-estradiol (E2) may be formed during estrone (E1) reduction to E2 by 17-β-hydroxysteroid dehydrogenase type 1 (HSD17B1). Therefore, we studied the HSD17B1 transcript and protein levels in primary nontumoral and tumoral gastric tissue from the same 21 patients with gastric cancer (GC). We also assessed the effect of 5-Aza-2'-deoxycytidine (5-dAzaC), on the methylation status of HSD17B1 and its expression and conversion of E1 to E2 in HGC-27 and EPG 85-257 GC cells. We identified the presence of HSD17B1 transcript and protein in HGC-27 and EPG 85-257 GC cells as well as in primary nontumoral and tumoral tissues from patients with GC. Moreover, we found that 5-dAzaC significantly up-regulated the HSD17B1 transcript and protein levels, which is associated with increased conversion of E1 to E2 in HGC-27 and EPG 85-257 GC cells. The changes in HSD17B1 expression in both HGC-27 and EPG 85-257 cells were accompanied by 5-dAzaC induced DNA demethylation in the 5' flanking region. Our results demonstrated that HSD17B1 expression and its ability to convert the weak estrogen E1 to the more potent E2 can be associated with DNA methylation in the 5' flanking region in GC cells.

Molecular cloning and expression of 17β-hydroxysteroid dehydrogenase type 2 gene in Hu sheep

17β-Hydroxysteroid dehydrogenase type 2 (17β-HSD2) catalyzes the NADP+-dependent oxidation of the most potent estrogen 17β-estradiol into the weak estrogen estrone, and the conversion of testosterone to androstenedione. It has been reported that 17β-HSD2 was expressed in many tissues in human, rats, however, the full-length sequence of 17β-HSD2 gene and its expression in ewe were still unknown. In this study, we cloned the full-length cDNA sequence and investigated mRNA differential expression in 28 tissues of 12 adult Hu-Sheep which were fed with high- and low- dietary intake. The 1,317 bp full-length cDNA sequence was first cloned. The coding region was 1,167 bp in length, and the monomer was estimated to contain 389 amino acid residues. It shares high AA sequence identity with that of bos Taurus (96.13 %), sus scrofa (77.06 %), canis lupus familiaris (70.44 %), Callithrix jacchus (65.72 %), Nomascus leucogenys (65.46 %), pan troglodytes (65.21 %), human (64.69 %), mus musculus (58.35 %), and a comparatively lower identity to danio rerio (37.85 %). 17β-HSD2 gene was high expressed in gastrointestinal (GI) tract, liver, but weakly expressed in other tissues. No detected expression was examined in lung. 17β-HSD2 gene expression was significantly difference in rumen, omasum, duodenum, cecum, hypophysis after high- and low- dietary intake. Results from the present study suggested that 17β-HSD2 plays a crucial role in almost all tissues protecting against excessive levels of active steroid hormone, and GI tract maybe an important steroid hormone metabolizing organ in Hu-Sheep. This present study is the first to provide the primary foundation for further insight into this ovine gene.

Male-dominant activation of rat renal organic anion transporter 1 (Oat1) and 3 (Oat3) expression by transcription factor BCL6

Background

Organic anion transporters 1 (Oat1) and 3 (Oat3) mediate the transport of organic anions, including frequently prescribed drugs, across cell membranes in kidney proximal tubule cells. In rats, these transporters are known to be male-dominant and testosterone-dependently expressed. The molecular mechanisms that are involved in the sex-dependent expression are unknown. Our aim was to identify genes that show a sex-dependent expression and could be involved in male-dominant regulation of Oat1 and Oat3.

Methodology/Principal Findings

Promoter activities of Oat1 and Oat3 were analyzed using luciferase assays. Expression profiling was done using a SurePrint G3 rat GE 8×60K microarray. RNA was isolated from renal cortical slices of four adult rats per sex. To filter the achieved microarray data for genes expressed in proximal tubule cells, transcription database alignment was carried out. We demonstrate that predicted androgen response elements in the promoters of Oat1 and Oat3 are not functional when the promoters were expressed in OK cells. Using microarray analyses we analyzed 17,406 different genes. Out of these genes, 56 exhibit a sex-dependent expression in rat proximal tubule cells. As genes potentially involved in the regulation of Oat1 and Oat3 expression, we identified, amongst others, the male-dominant hydroxysteroid (17-beta) dehydrogenase 1 (Hsd17b1), B-cell CLL/lymphoma 6 (BCL6), and polymerase (RNA) III (DNA directed) polypeptide G (Polr3g). Moreover, our results revealed that the transcription factor BCL6 activates promoter constructs of Oat1 and Oat3.

Conclusion

The results indicate that the male-dominant expression of both transporters, Oat1 and Oat3, is possibly not directly regulated by the classical androgen receptor mediated transcriptional pathway but appears to be regulated by the transcription factor BCL6.