Inhibitory effects of parabens on human and rat 17ß-hydroxysteroid dehydrogenase 1: Mechanisms of action and impact on hormone synthesis.

Parabens are commonly used preservatives in cosmetics, food, and pharmaceutical products. The objective of this study was to examine the effect of nine parabens on human and rat 17ß-hydroxysteroid dehydrogenase 1 (17ß-HSD1) in human placental and rat ovarian cytosols, as well as on estradiol synthesis in BeWo cells. The results showed that the IC50 values for these compounds varied from methylparaben with the weakest inhibition (106.42 µM) to hexylparaben with the strongest inhibition (2.05 µM) on human 17ß-HSD1. Mode action analysis revealed that these compounds acted as mixed inhibitors. For rats, the IC50 values ranged from the weakest inhibition for methylparaben (no inhibition at 100 µM) to the most potent inhibition for hexylparaben (0.87 µM), and they functioned as mixed inhibitors. Docking analysis indicated that parabens bind to the region bridging the NADPH and steroid binding sites of human 17ß-HSD1 and the NADPH binding site of rat 17ß-HSD1. Bivariate correlation analysis demonstrated negative correlations between LogP, molecular weight, heavy atoms, and apolar desolvation energy, and the IC50 values of these compounds. In conclusion, this study identified the inhibitory effects of parabens and their binding mechanisms on human and rat 17ß-HSD1, as well as their impact on hormone synthesis.

Identification of Hydroxysteroid Dehydrogenase Type 1 As a Potential Bladder Tumor Marker.

Background: The 17beta-hydroxysteroid dehydrogenase type 1 (HSD17B) family has been implicated in the prognosis and treatment prediction of various malignancies; however, its association with bladder cancer (BLCA) remains unclear. This study aimed to evaluate the potential of HSD17B1, as a prognostic biomarker, for the survival of patients with BLCA and to determine its effectiveness as a supplemental biomarker for BLCA. Methods: A series of bioinformatics techniques were applied to investigate the expression of HSD17B1 in different types of cancer and its potential association with the prognosis of BLCA patients using diverse databases. The UALCAN, Human Protein Atlas, cBioPortal, Metascape, GEPIA, MethSurv, and TIMER were employed to analyze expression differences, mutation status, enrichment analysis, overall survival, methylation, and immune-infiltrating cells. The real-time reverse transcription-PCR (qRT-PCR) was implemented to detect the messenger ribonucleic acid (mRNA) expression levels of HSD17B1 in vitro. Results: Elevated mRNA and protein levels of HSD17B1, surpassing normal levels, were observed in BLCA samples. In addition, the BLCA patients with higher mRNA expression level of HSD17B1 significantly reduced the overall survival. Also, several immune infiltrating cells, including mast cell resting CIBERSORT-ABS, have been identified as tumor-associated biomarker genes, with the potential to significantly influence the immunological environment. Finally, qRT-PCR analysis revealed a significant upregulation of HSD17B1 mRNA expression level in the cancer cells compared to the human 293T cells, which was consistent with the bioinformatics data. Conclusion: There is a strong correlation between the elevated HSD17B1 expression and positive prognosis in patients with BLCA. Therefore, HSD17B1 can be used as a prognostic biomarker in these patients.

HSD17B1 Compensates for HSD17B3 Deficiency in Fetal Mouse Testis but Not in Adults.

Hydroxysteroid (17ß) dehydrogenase (HSD17B) enzymes convert 17-ketosteroids to 17beta-hydroxysteroids, an essential step in testosterone biosynthesis. Human XY individuals with inactivating HSD17B3 mutations are born with female-appearing external genitalia due to testosterone deficiency. However, at puberty their testosterone production reactivates, indicating HSD17B3-independent testosterone synthesis. We have recently shown that Hsd17b3 knockout (3-KO) male mice display a similar endocrine imbalance, with high serum androstenedione and testosterone in adulthood, but milder undermasculinization than humans. Here, we studied whether HSD17B1 is responsible for the remaining HSD17B activity in the 3-KO male mice by generating a Ser134Ala point mutation that disrupted the enzymatic activity of HSD17B1 (1-KO) followed by breeding Hsd17b1/Hsd17b3 double-KO (DKO) mice. In contrast to 3-KO, inactivation of both HSD17B3 and HSD17B1 in mice results in a dramatic drop in testosterone synthesis during the fetal period. This resulted in a female-like anogenital distance at birth, and adult DKO males displayed more severe undermasculinization than 3-KO, including more strongly reduced weight of seminal vesicles, levator ani, epididymis, and testis. However, qualitatively normal spermatogenesis was detected in adult DKO males. Furthermore, similar to 3-KO mice, high serum testosterone was still detected in adult DKO mice, accompanied by upregulation of various steroidogenic enzymes. The data show that HSD17B1 compensates for HSD17B3 deficiency in fetal mouse testis but is not the enzyme responsible for testosterone synthesis in adult mice with inactivated HSD17B3. Therefore, other enzymes are able to convert androstenedione to testosterone in the adult mouse testis and presumably also in the human testis.

Evolution of a novel adrenal cell type that promotes parental care.

Cell types with specialized functions fundamentally regulate animal behaviour, and yet the genetic mechanisms that underlie the emergence of novel cell types and their consequences for behaviour are not well understood1. Here we show that the monogamous oldfield mouse (Peromyscus polionotus) has recently evolved a novel cell type in the adrenal gland that expresses the enzyme AKR1C18, which converts progesterone into 20α-hydroxyprogesterone. We then demonstrate that 20α-hydroxyprogesterone is more abundant in oldfield mice, where it induces monogamous-typical parental behaviours, than in the closely related promiscuous deer mice (Peromyscus maniculatus). Using quantitative trait locus mapping in a cross between these species, we ultimately find interspecific genetic variation that drives expression of the nuclear protein GADD45A and the glycoprotein tenascin N, which contribute to the emergence and function of this cell type in oldfield mice. Our results provide an example by which the recent evolution of a new cell type in a gland outside the brain contributes to the evolution of social behaviour.

An integrated approach of network pharmacology, molecular docking, and experimental verification uncovers kaempferol as the effective modulator of HSD17B1 for treatment of endometrial cancer.

BACKGROUND: Endometrial cancer (EC) is one of the most common gynecological malignancies globally, and the development of innovative, effective drugs against EC remains a key issue. Phytoestrogen kaempferol exhibits anti-cancer effects, but the action mechanisms are still unclear. METHOD: MTT assays, colony-forming assays, flow cytometry, scratch healing, and transwell assays were used to evaluate the proliferation, apoptosis, cell cycle, migration, and invasion of both ER-subtype EC cells. Xenograft experiments were used to assess the effects of kaempferol inhibition on tumor growth. Next-generation RNA sequencing was used to compare the gene expression levels in vehicle-treated versus kaempferol-treated Ishikawa and HEC-1-A cells. A network pharmacology and molecular docking technique were applied to identify the anti-cancer mechanism of kaempferol, including the building of target-pathway network. GO analysis and KEGG pathway enrichment analysis were used to identify cancer-related targets. Finally, the study validated the mRNA and protein expression using real-time quantitative PCR, western blotting, and immunohistochemical analysis. RESULTS: Kaempferol was found to suppress the proliferation, promote apoptosis, and limit the tumor-forming, scratch healing, invasion, and migration capacities of EC cells. Kaempferol inhibited tumor growth and promotes apoptosis in a human endometrial cancer xenograft mouse model. No significant toxicity of kaempferol was found in human monocytes and normal cell lines at non-cytotoxic concentrations. No adverse effects or significant changes in body weight or organ coefficients were observed in 3-7 weeks' kaempferol-treated animals. The RNA sequencing, network pharmacology, and molecular docking approaches identified the overall survival-related differentially expressed gene HSD17B1. Interestingly, kaempferol upregulated HSD17B1 expression and sensitivity in ER-negative EC cells. Kaempferol differentially regulated PPARG expression in EC cells of different ER subtypes, independent of its effect on ESR1. HSD17B1 and HSD17B1-associated genes, such as ESR1, ESRRA, PPARG, AKT1, and AKR1C1\2\3, were involved in several estrogen metabolism pathways, such as steroid binding, 17-beta-hydroxysteroid dehydrogenase (NADP+) activity, steroid hormone biosynthesis, and regulation of hormone levels. The molecular basis of the effects of kaempferol treatment was evaluated. CONCLUSIONS: Kaempferol is a novel therapeutic candidate for EC via HSD17B1-related estrogen metabolism pathways. These results provide new insights into the efficiency of the medical translation of phytoestrogens.

Overexpression of Human Estrogen Biosynthetic Enzyme Hydroxysteroid (17beta) Dehydrogenase Type 1 Induces Adenomyosis-like Phenotype in Transgenic Mice.

Hydroxysteroid (17beta) dehydrogenase type 1 (HSD17B1) is an enzyme that converts estrone to estradiol, while adenomyosis is an estrogen-dependent disease with poorly understood pathophysiology. In the present study, we show that mice universally over-expressing human estrogen biosynthetic enzyme HSD17B1 (HSD17B1TG mice) present with adenomyosis phenotype, characterized by histological and molecular evaluation. The first adenomyotic changes with endometrial glands partially or fully infiltrated into the myometrium appeared at the age of 5.5 months in HSD17B1TG females and became more prominent with increasing age. Preceding the phenotype, increased myometrial smooth muscle actin positivity and increased amount of glandular myofibroblast cells were observed in HSD17B1TG uteri. This was accompanied by transcriptomic upregulation of inflammatory and estrogen signaling pathways. Further, the genes upregulated in the HSD17B1TG uterus were enriched with genes previously observed to be induced in the human adenomyotic uterus, including several genes of the NFKB pathway. A 6-week-long HSD17B1 inhibitor treatment reduced the occurrence of the adenomyotic changes by 5-fold, whereas no effect was observed in the vehicle-treated HSD17B1TG mice, suggesting that estrogen is the main upstream regulator of adenomyosis-induced uterine signaling pathways. HSD17B1 is considered as a promising drug target to inhibit estrogen-dependent growth of endometrial disorders. The present data indicate that HSD17B1 over-expression in TG mice results in adenomyotic changes reversed by HSD17B1 inhibitor treatment and HSD17B1 is, thus, a potential novel drug target for adenomyosis.

Maternal 11-Ketoandrostenedione Rises Through Normal Pregnancy and Is the Dominant 11-Oxygenated Androgen in Cord Blood.

CONTEXT: Adrenal-derived 11-oxygenated androgens (11oAs) are known important contributors to human physiology and disease but have not been studied in pregnancy. OBJECTIVE: We characterize 11oAs in normal human pregnancy and neonatal period and assess the ratios between 11oAs and compare with ratios of other steroids that undergo placental metabolism. DESIGN: Prospective cohort study, 2010-2018. SETTING: Academic institution. PATIENTS: Pairs of pregnant women and newborns (n = 120) were studied. Inclusion criteria were maternal age between 18 and 42 years old, spontaneous singleton pregnancies, and intention to deliver at University of Michigan. INTERVENTION: Maternal venous blood was collected during first trimester and at term. Neonatal cord blood was collected following delivery. Steroids were measured via liquid chromatography-tandem mass spectrometry. MAIN OUTCOME MEASURES: Levels of 11ß-hydroxyandrostenedione (11OHA4), 11-ketoandrostenedione (11KA4), 11ß-hydroxytestosterone, and 11-ketotestoterone (11KT) in maternal first trimester, maternal term, and neonatal cord blood were compared. 11OHA4-to-11KA4 ratios were correlated with cortisol-to-cortisone ratios. RESULTS: Dominant 11oAs in pregnancy and the cord blood are 11OHA4 and 11KA4, compared to 11OHA4 and 11KT in adult men and nonpregnant women. We found a rise in 11oA concentrations, particularly 11KA4, from first to third trimester. In cord blood, the concentration of 11KA4 exceeded those of both 11OHA4 and 11KT, reflecting placental 11ß-hydroxysteroid dehydrogenase type 2 (11ßHSD2) and 17ß-hydroxysteroid dehydrogenase (17ßHSD2) activities, respectively. 11OHA4-to-11KA4 ratios are concordant with cortisol-to-cortisone ratios across all maternal and fetal compartments, reflecting placental 11ßHSD2 activity. CONCLUSIONS: Placental 17ßHSD2 activity defends the fetus against the androgen 11KT. Our normative values may be used in future studies of 11oAs in complicated pregnancies.

Steroid-converting enzymes in human adipose tissues and fat deposition with a focus on AKR1C enzymes.

Adipocytes express various enzymes, such as aldo-keto reductases (AKR1C), 11ß-hydroxysteroid dehydrogenase (11ß-HSD), aromatase, 5α-reductases, 3ß-HSD, and 17ß-HSDs involved in steroid hormone metabolism in adipose tissues. Increased activity of AKR1C enzymes and their expression in mature adipocytes might indicate the association of these enzymes with subcutaneous adipose tissue deposition. The inactivation of androgens by AKR1C enzymes increases adipogenesis and fat mass, particularly subcutaneous fat. AKR1C also causes reduction of estrone, a weak estrogen, to produce 17ß-estradiol, a potent estrogen and, in addition, it plays a role in progesterone metabolism. Functional impairments of adipose tissue and imbalance of steroid biosynthesis could lead to metabolic disturbances. In this review, we will focus on the enzymes involved in steroid metabolism and fat tissue deposition.

Differential expression of genes involved in steroidogenesis pathway in human oocytes obtained from patients with polycystic ovaries.

OBJECTIVE: Follicular development can be disturbed due to many factors, including having polycystic ovaries. Aberrant expression of genes involved in steroidogenesis pathway could lead to aberrant oocyte development. In this study, the gene expression levels of a number of genes that is functioning in steroidogenesis pathway were investigated. MATERIALS AND METHODS: The spare oocytes were collected from NEU Hospital IVF Center following controlled ovarian stimulation cycle. RNA was extracted using RNA/DNA Purification Kit (Norgen, Canada) and reverse transcription was performed using TruScript First Strand cDNA Synthesis Kit (Norgen, Canada). Real time PCR was conducted using LightCycler® 480 SYBR Green I Master (Roche, UK). RESULTS AND CONCLUSION: The expression levels of CYP11, CYP17, CYP19, HSD17B1, HSD3B2 and ACTB were detected in human MII stage oocytes obtained from oocyte donors aged between 18-30 years. The number of follicles and oocytes collected from the patients with polycystic ovaries were slightly higher compared to the control group. The expression level of CYP11A1 was shown to be statistically different in the oocytes obtained from the patients who do not have polycystic ovaries (p < 0.05), whereas statistically significant expression levels were observed for CYP17 in the oocytes obtained from patients with polycystic ovaries (p < 0.05). The expression level of HSD17B1 was also shown to be statistically different in the oocytes (p < 0.05). The extrapolation of the results indicates that the genes involved in steroidogenesis pathway are altered in cases of polycystic ovaries. Thus, it may have a role in the development of polycystic ovaries.

Estrogen Formation and Inactivation Following TBI: What we Know and Where we Could go.

Traumatic brain injury (TBI) is responsible for various neuronal and cognitive deficits as well as psychosocial dysfunction. Characterized by damage inducing neuroinflammation, this response can cause an acute secondary injury that leads to widespread neurodegeneration and loss of neurological function. Estrogens decrease injury induced neuroinflammation and increase cell survival and neuroprotection and thus are a potential target for use following TBI. While much is known about the role of estrogens as a neuroprotective agent following TBI, less is known regarding their formation and inactivation following damage to the brain. Specifically, very little is known surrounding the majority of enzymes responsible for the production of estrogens. These estrogen metabolizing enzymes (EME) include aromatase, steroid sulfatase (STS), estrogen sulfotransferase (EST/SULT1E1), and some forms of 17ß-hydroxysteroid dehydrogenase (HSD17B) and are involved in both the initial conversion and interconversion of estrogens from precursors. This article will review and offer new prospective and ideas on the expression of EMEs following TBI.

Lepidiline A Improves the Balance of Endogenous Sex Hormones and Increases Fecundity by Targeting HSD17B1.

SCOPE: Maca (Lepidium meyenii), a well-known plant from the Andean highlands of Peru, has been used widely as a nutritional supplement to increase sexual function and fecundity. However, the identity of its active ingredients and how they function remain unknown. METHODS AND RESULTS: Chemical substances in maca are identified by UPLC-Q-TOF, and the active ingredients are screened through HotMap coupled with an artificial neural network. Lepidiline A (LA), an imidazole alkaloid, is identified as the key active compound. LA affects the balance of endogenous sex hormones in mice and improves fecundity in Drosophila. Using a molecular LA probe, 17ß-hydroxysteroid dehydrogenase type 1 (HSD17B1) is revealed to be the potential target of LA using a fishing-rod strategy. It is demonstrated with experimental data that LA targets HSD17B1 to enhance the enzyme's activity and increases its bioconversion efficiency of actively formed sex hormones including estrogen to 17ß-estradiol and 4-androsten-3,7-dione to testosterone, which ultimately improves reproductive activity. CONCLUSION: LA improves the balance of endogenous sex hormones and increases fecundity by targeting HSD17B1. This underlying mechanism of action provides a useful insight into the application of maca in the regulation of dietary nutrition and healthy fertility.

Altered expression of 17­ß­hydroxysteroid dehydrogenase type 2 and its prognostic significance in non­small cell lung cancer.

Numerous studies have reported that oestrogens may contribute to the development of non­small cell lung cancer (NSCLC). Although different steroidogenic enzymes have been detected in the lung, the precise mechanism leading to an exaggerated accumulation of active oestrogens in NSCLC remains unexplained. 17­ß­Hydroxysteroid dehydrogenase type 2 (HSD17B2) is an enzyme involved in oestrogen and androgen inactivation by converting 17­ß­oestradiol into oestrone, and testosterone into 4­androstenedione. Therefore, the enzyme serves an important role in regulation of the intracellular availability of active sex steroids. This study aimed to determine the expression levels of HSD17B2 in lung cancer (LC) and adjacent histopathologically unchanged tissues obtained from 161 patients with NSCLC, and to analyse the association of HSD17B2 with clinicopathological features. For that purpose, reverse transcription­quantitative PCR, western blotting and immunohistochemistry were conducted. The results revealed that the mRNA and protein expression levels of HSD17B2 were significantly decreased in LC tissues compared with matched controls (P<10­6). Conversely, strong cytoplasmic staining of HSD17B2 was detected in the unchanged respiratory epithelium and in glandular cells. Notably, a strong association was detected between reduced HSD17B2 expression and advanced tumour stage, grade and size. Furthermore, it was revealed that HSD17B2 may have potential prognostic significance in NSCLC. A log­rank test revealed the benefit of high HSD17B2 protein expression for the overall survival (OS) of patients (P=0.0017), and multivariate analysis confirmed this finding (hazard ratio=0.21; 95% confidence interval=0.07­0.63; P=0.0043). Stratified analysis in the Kaplan­Meier Plotter database indicated that patients with higher HSD17B2 expression presented better OS and post­progression survival. This beneficial effect was particularly evident in patients with adenocarcinoma and during the early stages of NSCLC. Decreased expression of HSD17B2 appears to be a frequent feature in NSCLC. Retrospective analysis suggests that the HSD17B2 mRNA and protein status might be independent prognostic factors in NSCLC and should be further investigated.

Local Epidermal Endocrine Estrogen Protects Human Melanocytes against Oxidative Stress, a Novel Insight into Vitiligo Pathology.

As the outermost barrier of the body, skin is a major target of oxidative stress. In the brain, estrogen has been reported synthesized locally and protects neurons from oxidative stress. Here, we explored whether estrogen is also locally synthesized in the skin to protect from oxidative stress and whether aberrant local estrogen synthesis is involved in skin disorders. Enzymes and estrogen receptor expression in skin cells were examined first by quantitative real-time PCR and Western blot analyses. Interestingly, the estrogen synthesis enzyme was mainly localized in epidermal keratinocytes and estrogen receptors were mainly expressed in melanocytes among 13 kinds of cultured human skin cells. The most abundant estrogen synthesis enzyme expressed in the epidermis was 17ß-hydroxysteroid dehydrogenase 1 (HSD17ß1) localized in keratinocytes, and the most dominant estrogen receptor expressed in the epidermis was G protein-coupled estrogen receptor 1 (GPER1) in melanocytes. To investigate whether keratinocyte-derived estradiol could protect melanocytes from oxidative stress, cultured human primary epidermal melanocytes (HEMn-MPs) were treated with H2O2 in the presence or absence of 17ß estradiol or co-cultured with HSD17ß1 siRNA-transfected keratinocytes. Keratinocyte-derived estradiol exhibited protective effects against H2O2-induced cell death. Further, reduced expression of HSD17ß1 in the epidermis of skin from vitiligo patients was observed compared to the skin from healthy donors or in the normal portions of the skin in vitiligo patients. Our results suggest a possible new target for interventions that may be used in combination with current therapies for patients with vitiligo.

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.

Potential role of microRNA-424 in regulating ERRγ to suppress trophoblast proliferation and invasion in fetal growth restriction.

BACKGROUND: Abnormal expression of estrogen-related receptor γ (ERRγ) protein is associated with fetal growth restriction (FGR). The upstream regulators of ERRγ are still unknown. OBJECTIVE: To evaluate the placental expression level of microRNA-424 (miR-424) and to demonstrate the relationship between miR-424 and FGR. METHODS: The expression levels of miR-424 were detected in FGR and control placentas. HTR-8/SVneo cells were transfected with mimics or inhibitors to increase or decrease the miR-424 expression level, respectively. The transwell and CCK-8 assays were used to determine trophoblast-derived cell line invasion and proliferation. The expression levels of miR-424, ERRγ, and 17 beta-hydroxysteroid dehydrogenase type 1 (HSD17B1) were detected by qRT-PCR and Western blotting. The relationship between miR-424, ERRγ, and HSD17B1 was determined by luciferase reporter assay. RESULTS: Compared to the normal pregnancy group, FGR placental tissues showed a significantly higher expression level of miR-424. The up-regulation of miR-424 decreased trophoblast-derived cell line invasion and proliferation. Down-regulation of miR-424 enhanced invasive and proliferative abilities of the cell lines. Over-expression of miR-424 reduced ERRγ protein levels and decreased both mRNA and protein levels of HSD17B1. Thus down-regulation of miR-424 induced protein expression of ERRγ and enhanced the mRNA and protein expressions of HSD17B1. MiR-424 probably mediated the expression of ERRγ via binding to sites other than mRNA 3'UTR. CONCLUSION: MiR-424 may be associated with the pathogenesis of FGR by modulating trophoblast-derived cell line proliferation and invasion. MiR-424 may play a role in mediating the protein expressions of ERRγ and HSD17B1.

Design, Synthesis, and Biological Characterization of Orally Active 17ß-Hydroxysteroid Dehydrogenase Type 2 Inhibitors Targeting the Prevention of Osteoporosis.

Osteoporosis is predominantly treated with drugs that inhibit further bone resorption due to estrogen deficiency. Yet, osteoporosis drugs that not only inhibit bone resorption but also stimulate bone formation, such as potentially inhibitors of 17ß-hydroxysteroid dehydrogenase type 2 (17ß-HSD2), may be more efficacious in the treatment of osteoporosis. Blockade of 17ß-HSD2 is thought to increase intracellular estradiol and testosterone in bone, thereby inhibiting bone resorption by osteoclasts and stimulating bone formation by osteoblasts, respectively. We here describe the design, synthesis, and biological characterization of a novel bicyclic-substituted hydroxyphenylmethanone 17ß-HSD2 inhibitor (compound 24). Compound 24 is a nanomolar potent inhibitor of human 17ß-HSD2 (IC50 of 6.1 nM) and rodent 17ß-HSD2 with low in vitro cellular toxicity, devoid of detectable estrogen receptor α affinity, displays high aqueous solubility and in vitro metabolic stability, and has an excellent oral pharmacokinetic profile for testing in a rat osteoporosis model. Administration of 24 in a rat osteoporosis model demonstrates its bone-sparing efficacy.

Development of potential preclinical candidates with promising in vitro ADME profile for the inhibition of type 1 and type 2 17ß-Hydroxysteroid dehydrogenases: Design, synthesis, and biological evaluation.

Estrogens are the major female sex steroid hormones, estradiol (E2) being the most potent form in humans. Disturbing the balance between E2 and its weakly active oxidized form estrone (E1) leads to diverse types of estrogen-dependent diseases such as endometriosis or osteoporosis. 17ß-Hydroxysteroid dehydrogenase type 1 (17ß-HSD1) catalyzes the biosynthesis of E2 by reduction of E1 while the type 2 enzyme catalyzes the reverse reaction. Thus, 17ß-HSD1 and 17ß-HSD2 are attractive targets for treatment of estrogen-dependent diseases. Recently, we reported the first proof-of-principle study of a 17ß-HSD2 inhibitor in a bone fracture mouse model, using subcutaneous administration. In the present study, our aim was to improve the in vitro ADME profile of the most potent 17ß-HSD1 and 17ß-HSD2 inhibitors described so far. The optimized compounds show strong and selective inhibition of both the human enzymes and their murine orthologs. In addition, they display good metabolic stability in human liver microsomes (S9 fraction), low in vitro cytotoxicity as well as better aqueous solubility and physicochemical properties compared to the lead compounds. These achievements make the compounds eligible for testing in preclinical in vivo animal model studies on the effects of inhibition of 17ß-HSD1 and 17ß-HSD2.

siRNA-based breast cancer therapy by suppressing 17ß-hydroxysteroid dehydrogenase type 1 in an optimized xenograft cell and molecular biology model in vivo.

PURPOSE: Hormone-dependent breast cancer is the most common form of breast cancer, and inhibiting 17ß-HSD1 can play an attractive role in decreasing estrogen and cancer cell proliferation. However, the majority of existing inhibitors have been developed from estrogens and inevitably possess residual estrogenicity. siRNA knockdown provides a highly specific way to block a targeted enzyme, being especially useful to avoid estrogenicity. Application of 17ß-HSD1-siRNA in vivo is limited by the establishment of an animal model, as well as the potential nuclease activity in vivo. We tried to reveal the in vivo potential of 17ß-HSD1-siRNA-based breast cancer therapy. MATERIALS AND METHODS: To establish a competent animal model, daily subcutaneous injection of an estrone micellar aqueous solution was adopted to provide the substrate for estradiol biosynthesis. The effects of three different doses of estrone (0.1, 0.5, and 2.5 µg/kg/day) on tumor growth in T47D-17ß-HSD1-inoculated group were investigated and compared with the animals inoculated with wild type T47D cells. To solve in vivo delivery problem of siRNA, "17ß-HSD1-siRNA/LPD", a PEGylated and modified liposome-polycation-DNA nanoparticle containing 17ß-HSD1-siRNA was prepared by the thin film hydration method and postinsertion technology. Finally, "17ß-HSD1-siRNA/LPD" was tested in the optimized model. Tumor growth and 17ß-HSD1 expression were assessed. RESULTS: Comparison with the untreated group revealed significant suppression of tumor growth in "17ß-HSD1-siRNA/LPD"-treated group when HSD17B1 gene expression was knocked down. CONCLUSION: These findings showed promising in vivo assessments of 17ß-HSD1-siRNA candidates. This is the first report of an in vivo application of siRNA for steroid-converting enzymes in a nude mouse model.

The Impact of Variants in Genes Associated with Estradiol Synthesis on Hormone Levels and Oocyte Retrieval in Patients Who Underwent Controlled Ovarian Hyperstimulation.

AIMS: To correlate differences in estradiol levels in serum and follicular fluid with genetic variants and to determine if they play a role in the results following assisted reproductive technology (ART). PATIENTS AND METHODS: A cross-sectional study was developed at the Ideia Fértil Institute of Reproductive Health. Two hundred two female patients were selected and underwent controlled ovarian hyperstimulation cycles. Patients for this study were chosen based on their male partners' infertility. Genotypes of selected variants of CYP19A1, CYP17A1, HSD17, and COMT were compared to the estradiol measurements from follicular fluid and serum, as well as to the number and maturation status of the oocytes retrieved. RESULTS: Patients with the variant homozygous genotype AA of CYP19A1 (rs10046) showed increased serum concentrations of estradiol when compared to patients with other genotypes (p = 0.005). The same polymorphism effect was not observed in follicular fluid. This CYP19A1 variant did not affect the number of oocytes recovered nor their maturation level. CONCLUSION: The CYP19A1 variant is associated with an estradiol imbalance in serum. Other pathways, however, may contribute to the formation of the final estradiol metabolite in follicular fluid as well as its impact on the oocyte maturation.