Estrogen signaling in the regulation of female reproductive functions

Arginine vasopressin injection rescues delayed oviposition in cyp19a1b-/- mutant female zebrafish

In zebrafish, estrogens produced in the ovaries via Cyp19a1a activity are required for both sexual differentiation of the ovary during early development as well as maintenance of the ovarian state during adulthood. The importance of Cyp19a1b that is highly expressed in the brain for female reproduction is still under study. We previously reported that female cyp19a1b -/- mutant zebrafish have significantly lower brain estradiol levels and impaired spawning behavior characterized by an increased latency to oviposition during dyadic sexual behavior encounters. In the current study, we provide evidence that the delayed oviposition in female cyp19a1b -/- mutants is linked to impaired arginine vasopressin (Avp) signaling. Droplet digital PCR experiments revealed that levels of the estrogen receptors, avp, and oxytocin (oxt) are lower in the hypothalamus of mutant females compared to wildtype fish. We then used acute intraperitoneal injections of Avp and Oxt, along with mixtures of their respective receptor antagonists, to determine that Avp can uniquely rescue the delayed oviposition in female cyp19a1b -/- mutants. Using immunohistochemistry, we demonstrated that Cyp19a1b-expressing radial glial cell (RGC) fibers surround and are in contact with Avp-immunopositive neurons in the preoptic areas of the brain. This could provide the neuroanatomical proximity for RGC-derived estrogens to diffuse to and activate estrogen receptors and regulate avp expression levels. Together these findings identify a positive link between Cyp19a1b and Avp for female zebrafish sexual behavior. They also suggest that the female cyp19a1b -/- mutant behavioral phenotype is likely a consequence of impaired processing of Avp-dependent social cues important for mate identification and assessment.

Hazardous radical-coupled transformation products of benzophenone-3 formed during manganese dioxide treatment

Radical-coupled transformation products (TPs) have been identified as the byproducts of various transformation processes, including both natural attenuation and artificial treatments, of phenolic micropollutants. Benzophenone-3 (BP-3), an organic UV filter of emerging concern, has been previously reported with ubiquitous occurrence in the natural environment and water bodies. Current research has demonstrated how TPs are formed from BP-3 when it is treated with manganese oxide (MnO2). The ecological and toxicological risks of these TPs have also been assessed. Polymerization of BP-3 through radical coupling was observed as the major pathway by which BP-3 is transformed when treated with MnO2. These radical-coupled TPs haven't shown further degradation after formation, suggesting their potential persistence once occurred in the environment. In silico experiments predict the radical-coupled TPs will increase in mobility, persistence and ecotoxicity. If true, they also represent an ever-increasing threat to the environment, ecosystems and, most immediately, aquatic living organisms. In addition, radical-coupled TPs produced by MnO2 transformation of BP-3 have shown escalated estrogenic activity compared to the parent compound. This suggests that radical coupling amplifies the toxicological impacts of parent compound. These results provide strong evidence that radical-coupled TPs with larger molecular sizes are having potential adverse impacts on the ecosystem and biota.

Embryonic signals mediate extracellular vesicle biogenesis and trafficking at the embryo-maternal interface

BACKGROUND

Extracellular vesicles (EVs) are membrane-coated nanoparticles secreted by almost all cell types in living organisms. EVs, as paracrine mediators, are involved in intercellular communication, immune response, and several reproductive events, including the maintenance of pregnancy. Using a domestic animal model (Sus scrofa) with an epitheliochorial, superficial type of placentation, we focused on EV biogenesis pathway at the embryo-maternal interface, when the embryonic signaling occurs for maternal recognition and the maintenance of pregnancy.

RESULTS

Transmission electron microscopy was used during early pregnancy to visualize EVs and apocrine and/or merocrine pathways of secretion. Immunofluorescent staining localized proteins responsible for EV biogenesis and cell polarization at the embryo-maternal interface. The expression profiles of genes involved in biogenesis and the secretion of EVs pointed to the possible modulation of endometrial expression by embryonic signals. Further in vitro studies showed that factors of embryonic origin can regulate the expression of the ESCRT-II complex and EV trafficking within endometrial luminal epithelial cells. Moreover, miRNA-mediated rapid negative regulation of gene expression was abolished by delivered embryonic signals.

CONCLUSIONS

Our findings demonstrated that embryonic signals are potent modulators of ESCRT-dependent EV-mediated secretory activity of the endometrium during the critical stages of early pregnancy. Video Abstract.

Mutation of brain aromatase disrupts spawning behavior and reproductive health in female zebrafish

Aromatase (Cyp19a1) is the steroidogenic enzyme that converts androgens into bioactive estrogens, and hence is in a pivotal position to mediate reproduction and sexual behavior. In teleosts, there are two aromatase paralogs: cyp19a1a that is highly expressed in granulosa and Leydig cells in the gonads with critical function in sexual differentiation of the ovary, and cyp19a1b that is highly expressed in radial glial cells in the brain with unknown roles in reproduction. Cyp19a1 ^-/- mutant zebrafish lines were used to investigate the importance of the cyp19a1 paralogs for spawning behavior and offspring survival and early development. Mutation of cyp19a1b was found to increase the latency to the first oviposition in females. Mutation of cyp19a1b in females also increased the number of eggs spawned; however, significantly more progeny died during early development resulting in no net increase in female fecundity. This finding suggests a higher metabolic cost of reproduction in cyp19a1b ^-/- mutant females. In males, the combined mutation of both cyp19a1 paralogs resulted in significantly lower progeny survival rates, indicating a critical function of cyp19a1 during early larval development. These data establish the specific importance of cyp19a1b for female spawning behavior and the importance of the cyp19a1 paralogs for early larval survival.

Oestrogen-induced epithelial-mesenchymal transition (EMT) in endometriosis: Aetiology of vaginal agenesis in Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome

Endometriosis occurs when endometrial-like tissue forms and grows outside the uterus due to oestrogen-induced epithelial-mesenchymal transition in the female reproductive tract. Factors that suppress this event could become potential therapeutic agents against disease occurrence and progression. However, an overview of these studies is still lacking. This review assessed the impact of a number factors on oestrogen-mediated epithelial-mesenchymal transition in the emergence of several diseases in the female reproductive tract, primarily endometriosis. The association between epithelial-mesenchymal transition and Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome was also investigated. Oestrogen, Wnt4 and epithelial-mesenchymal transition were chosen as keywords in Scopus, PubMed, and Web of Science searches performed on 28th June 2021. Study selection was refined to cancer-irrelevant, English, original articles published between years 2011-2021. The full-text assessment was carried out for topic-related articles after title and abstract screening. Included studies were summarised and assessed for their risk of bias using the Office of Health Assessment and Translation tool. In this review, 10 articles investigating oestrogen and epithelial-mesenchymal transition in the female reproductive tract were summarised and classified into two groups: seven studies under 'factor'-modulated epithelial-mesenchymal transition and three studies under 'factor'-manipulated oestrogen-induced epithelial-mesenchymal transition. The current evidence proposes that epithelial-mesenchymal transition is one of the prime causes of reproductive-related disease. This event could be mediated by distinct stimuli, specifically oestrogen and Wnt4 aberration. The results of this review suggest that oestrogen and Wnt4 participate in epithelial-mesenchymal transition in vaginal epithelial cells in MRKH syndrome, adopting from the theories of endometriosis development, which could therefore serve as a foundation for novel target treatment, specifically related to vaginal epithelialisation, to ensure better surgical outcomes.

Identification of Candidate Salivary, Urinary and Serum Metabolic Biomarkers for High Litter Size Potential in Sows (Sus scrofa)

The selection of sows that are reproductively fit and produce large litters of piglets is imperative for success in the pork industry. Currently, low heritability of reproductive and litter-related traits and unfavourable genetic correlations are slowing the improvement of pig selection efficiency. The integration of biomarkers as a supplement or alternative to the use of genetic markers may permit the optimization and increase of selection protocol efficiency. Metabolite biomarkers are an advantageous class of biomarkers that can facilitate the identification of cellular processes implicated in reproductive condition. Metabolism and metabolic biomarkers have been previously implicated in studies of female mammalian fertility, however a systematic analysis across multiple biofluids in infertile and high reproductive potential phenotypes has not been explored. In the current study, the serum, urinary and salivary metabolomes of infertile (INF) sows and high reproductive potential (HRP) sows with a live litter size ≥ 13 piglets were examined using LC-MS/MS techniques, and a data pipeline was used to highlight possible metabolite reproductive biomarkers discriminating the reproductive groups. The metabolomes of HRP and INF sows were distinct, including significant alterations in amino acid, fatty acid, membrane lipid and steroid hormone metabolism. Carnitines and fatty acid related metabolites were most discriminatory in separating and classifying the HRP and INF sows based on their biofluid metabolome. It appears that urine is a superior biofluid than saliva and serum for potentially predicting the reproductive potential level of a given female pig based on the performance of the resultant biomarker models. This study lays the groundwork for improving gilt and sow selection protocols using metabolomics as a tool for the prediction of reproductive potential.

COVID-19, Vaccination, and Female Fertility in the Czech Republic

The fast-track process to approve vaccines against COVID-19 has raised questions about their safety, especially in relation to fertility. Over the last 2 years, studies have appeared monitoring female fertility, especially from assisted reproduction centers or in animal experiments. However, studies monitoring healthy populations are still limited. The aim of our study was to monitor the relevant parameters of female fertility (sex and other steroids, LH, FSH, SHBG, Antimüllerian hormone and antral follicle count) before and then 2-4 months after the third dose of vaccination against COVID-19 in a group of 25 healthy fertile woman. In addition, anti-SARS-CoV-2 and anti-SARS-CoV-2S antibodies were determined. We did not observe significant changes in the measured parameters before and after the third dose of vaccination. By comparing levels of the analytes with antibodies indicating a prior COVID-19 infection, we found that women who had experienced the disease had statistically lower levels of estrone, estradiol, SHBG and 5α-dihydroprogesterone, and conversely, higher levels of androgen active dehydroepiandrosterone and dihydrotestosterone. Our results confirm that vaccination does not affect female fertility, and that what fertile women should be worried about is not vaccination, but rather COVID-19 infection itself.

Biomolecular Effects of Dance and Dance/Movement Therapy: A Review

The positive health impacts of dance and dance/movement therapy can be seen all the way down to the molecular level. This narrative-style review illustrates this connection by presenting a collection of clinical and preclinical studies that evaluate the effects of dance activities on hormones and other small-molecule metabolites within the human body. The results of these studies show that dance activities can increase levels of nitric oxide, serotonin, estrogen hormones, and HDL cholesterol, while they can decrease levels of dopamine, serum glucose, serum triglycerides, and LDL cholesterol. Levels of cortisol can either be increased or decreased, depending on the type of dance. Many of these results parallel the biomolecular effects of traditional (non-dance) exercise activities, although some contrasting results can also be seen. The concentrations of these molecules and their distributions throughout the body impact health and a wide variety of disease states. This connection to the molecular level provides a perspective for understanding how it is that dance activities are able to affect larger-scale physiological and psychological responses and lead to the positive health outcomes that are observed in many situations.

Assessment of Ferula hermonis Boiss fertility effects in immature female rats supported by quantification of ferutinin via HPLC and molecular docking

ETHNOPHARMACOLOGICAL RELEVANCE

Ferula hermonis is a small shrub renowned for its aphrodisiac abilities. Middle East herbalists have utilized Ferula hermonis seed and root as an aphrodisiac folk medicine to treat women's frigidity and male erectile and sexual dysfunction.

AIM OF THE STUDY

Assessment of follicle-stimulating hormone-like (FSH), luteinizing hormone-like (LH), and estrogenic activities of the methanolic extract (ME) of the roots of Ferula hermonis on female reproductive function.

MATERIALS AND METHODS

The methanolic extract was prepared from the root of F. hermonis and studied at dose level 6 mg/kg in immature female rats for FSH-like, LH-like, and estrogenic activities. These activities were determined by analyzing gross anatomical features, relative organ weight, and serum level of FSH, LH, progesterone and estrogen hormones, and histopathological characteristics. Quantification of the main phytoestrogenic component ferutinin carried out by HPLC. In addition, molecular docking for the binding affinity of ferutinin inside active sites of both estrogen receptor alpha (ERα) and FSH receptor (FSHR) was performed to predict the potential role of ferutinin in regulating the female reproductive process.

RESULTS

Ferula hermonis (ME) showed potent FSH-like, LH-like activities and moderate estrogenic effect at the dose of 6 mg/kg. The content of ferutinin in F. hermonis was estimated to be 92 ± 1.33 mg/g of the methanolic extract. Molecular docking of ferutinin with ERα and FSHR displayed strong interaction with target proteins.

CONCLUSIONS

Based on results, it can be concluded that Ferula hermonis can be considered as a suitable female fertility improving agent.

Endocrine disorders and fertility and pregnancy: An update

It is estimated that more and more couples suffer from fertility and pregnancy maintenance disorders. It is associated with impaired androgen secretion, which is influenced by many factors, ranging from genetic to environmental. It is also important to remember that fertility disorders can also result from abnormal anatomy of the reproductive male and female organ (congenital uterine anomalies - septate, unicornuate, bicornuate uterus; acquired defects of the uterus structure - fibroids, polyps, hypertrophy), disturbed hormonal cycle and obstruction of the fallopian tubes resulting from the presence of adhesions due to inflammation, endometriosis, and surgery, abnormal rhythm of menstrual bleeding, the abnormal concentration of hormones. There are many relationships between the endocrine organs, leading to a chain reaction when one of them fails to function properly. Conditions in which the immune system is involved, including infections and autoimmune diseases, also affect fertility. The form of treatment depends on infertility duration and the patient's age. It includes ovulation stimulation with clomiphene citrate or gonadotropins, metformin use, and weight loss interventions. Since so many different factors affect fertility, it is important to correctly diagnose what is causing the problem and to modify the treatment regimen if necessary. This review describes disturbances in the hormone secretion of individual endocrine organs in the context of fertility and the maintenance of pregnancy.

Facile fabrication of 17β-estradiol electrochemical sensor using polyaniline/carbon dot-coated glassy carbon electrode with synergistically enhanced electrochemical stability

Previous 17β-estradiol sensors required expensive reagents or complicated fabrication of sensing probes. In this work, a cheap, simple, and reusable electrochemical sensor based on commercially available polyaniline (PANI) and carbon dots (CDs) synthesized from iota-carrageenan was developed for the sensitive detection of 17β-estradiol. The sensor was simply prepared by drop-casting CDs/PANI composite on a glassy carbon electrode (GCE) using poly(vinylidene fluoride) as a binder. With synergistic contributions from both CDs and PANI, the CDs-PANI/GCE was much more electrochemically stable than the CDs/GCE or PANI/GCE. The CDs-PANI/GCE was sensitive to 17β-estradiol across a linear range from 0.001 to 100 μmol L^-1 with a detection limit of 43 nmol L^-1. The electrochemical measurement can be performed in 2 min and the probe can be reused for several hundred times. The CDs-PANI/GCE was selective towards 17β-estradiol against several interferences and gave excellent recovery between 94.4 and 103.7 % from real sample analysis. From intensive investigation on electron transfer process and energy levels, the oxidation reaction of 17β-estradiol occurred on the surface of CDs-PANI/GCE via favorable energy levels and dominantly surface adsorption process through π-π stacking and hydrogen bonding between 17β-estradiol and CDs/PANI. Such unique interfacial interactions also resulted in the synergistically enhanced electrochemical stability of the modified electrode.

Reproductive History and Age of Onset for Women Diagnosed with Amyotrophic Lateral Sclerosis: Data from the National ALS Registry: 2010-2018

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a neurological disease of largely unknown etiology with no cure. The National ALS Registry is a voluntary online system that collects demographic and reproductive history (females only) data from patients with ALS. We will examine the association between demographic and reproductive history among female patients aged >18 years and various ages of onset for ALS.

METHODS

Data from a cross-sectional study were collected and examined for 1,018 female ALS patients. Patient characteristics examined were demographics including race, BMI, and familial history of ALS. Among patients, information on reproductive history, including age at menopause, ever pregnant, and age at first pregnancy was collected. Unadjusted and adjusted logistic regression models were used to estimate OR and 95% CI in this study.

RESULTS

Women were more likely to be diagnosed with ALS before age 60 if they were nonwhite (p = 0.015), had attended college (p = 0.0012), had a normal BMI at age 40 (p < 0.0001), completed menopause before age 50 (p < 0.0001), and had never been pregnant (p = 0.046) in the univariate analysis. Women diagnosed with ALS before age 60 were also more likely to have limb site of onset (p < 0.0001). In the multivariate analysis, those who completed menopause before age 50 were more likely to be diagnosed with ALS before age 60 (OR = 1.8, 95% CI: 1.4-2.3) compared with women who completed menopause at or after age 50, after controlling for race, ever pregnant, age at first pregnancy, family history of ALS, education status, smoking history, and BMI at age 40. For women who were diagnosed with ALS before age 50, the odds of them entering menopause before age 50 climb to 48.7 (95% CI: 11.8, 200.9). The mean age of ALS diagnosis for women who completed menopause before age 50 was 58 years and 64 years for women who entered menopause after age 50 (p < 0.0001).

CONCLUSION

Women who reported completing menopause before age 50 were significantly more likely to be diagnosed with ALS before age 60 compared with those who reported entering menopause after age 50. More research is needed to determine the relationship between female reproductive history, especially regarding endogenous estrogen exposure and early-onset ALS.

Epigenetic Changes Associated With Exposure to Glyphosate-Based Herbicides in Mammals

Glyphosate is a phosphonomethyl amino acid derivative present in a number of non-selective and systemic herbicides. During the last years the use of glyphosate-based herbicide (GBH) has been increasing exponentially around the world, including Argentina. This fact added to the detection of glyphosate, and its main metabolite, amino methylphosphonic acid (AMPA), in environmental matrices such as soil, sediments, and food, has generated great concern about its risks for humans, animals, and environment. During the last years, there were controversy and intense debate regarding the toxicological effects of these compounds associated with the endocrine system, cancer, reproduction, and development. The mechanisms of action of GBH and their metabolites are still under investigation, although recent findings have shown that they could comprise epigenetic modifications. These are reversible mechanisms linked to tissue-specific silencing of gene expression, genomic imprinting, and tumor growth. Particularly, glyphosate, GBH, and AMPA have been reported to produce changes in global DNA methylation, methylation of specific genes, histone modification, and differential expression of non-coding RNAs in human cells and rodents. Importantly, the epigenome could be heritable and could lead to disease long after the exposure has ended. This mini-review summarizes the epigenetic changes produced by glyphosate, GBHs, and AMPA in humans and rodents and proposes it as a potential mechanism of action through which these chemical compounds could alter body functions.

Melatonin: Multi-Target Mechanism Against Diminished Ovarian Reserve Based on Network Pharmacology

BACKGROUND

Diminished ovarian reserve (DOR) significantly increases the risk of female infertility and contributes to reproductive technology failure. Recently, the role of melatonin in improving ovarian reserve (OR) has attracted widespread attention. However, details on the pharmacological targets and mechanisms of melatonin-improved OR remain unclear.

OBJECTIVE

A systems pharmacology strategy was proposed to elucidate the potential therapeutic mechanism of melatonin on DOR at the molecular, pathway, and network levels.

METHODS

The systems pharmacological approach consisted of target identification, data integration, network construction, bioinformatics analysis, and molecular docking.

RESULTS

From the molecular perspective, 26 potential therapeutic targets were identified. They participate in biological processes related to DOR development, such as reproductive structure development, epithelial cell proliferation, extrinsic apoptotic signaling pathway, PI3K signaling, among others. Eight hub targets (MAPK1, AKT1, EGFR, HRAS, SRC, ESR1, AR, and ALB) were identified. From the pathway level, 17 significant pathways, including the PI3K-Akt signaling pathway and the estrogen signaling pathway, were identified. In addition, the 17 signaling pathways interacted with the 26 potential therapeutic targets to form 4 functional modules. From the network point of view, by regulating five target subnetworks (aging, cell growth and death, development and regeneration, endocrine and immune systems), melatonin could exhibit anti-aging, anti-apoptosis, endocrine, and immune system regulation effects. The molecular docking results showed that melatonin bound well to all hub targets.

CONCLUSION

This study systematically and intuitively illustrated the possible pharmacological mechanisms of OR improvement by melatonin through anti-aging, anti-apoptosis, endocrine, and immune system regulation effects.

The Role of Estrogen Receptors and Their Signaling across Psychiatric Disorders

Increasing evidence suggests estrogen and estrogen signaling pathway disturbances across psychiatric disorders. Estrogens are not only crucial in sexual maturation and reproduction but are also highly involved in a wide range of brain functions, such as cognition, memory, neurodevelopment, and neuroplasticity. To add more, the recent findings of its neuroprotective and anti-inflammatory effects have grown interested in investigating its potential therapeutic use to psychiatric disorders. In this review, we analyze the emerging literature on estrogen receptors and psychiatric disorders in cellular, preclinical, and clinical studies. Specifically, we discuss the contribution of estrogen receptor and estrogen signaling to cognition and neuroprotection via mediating multiple neural systems, such as dopaminergic, serotonergic, and glutamatergic systems. Then, we assess their disruptions and their potential implications for pathophysiologies in psychiatric disorders. Further, in this review, current treatment strategies involving estrogen and estrogen signaling are evaluated to suggest a future direction in identifying novel treatment strategies in psychiatric disorders.

In Vitro Maturation of Fully Grown Mouse Antral Follicles in the Presence of 1 nM 2-Hydroxyestradiol Improves Oocytes' Developmental Competence

Cathecolestrogens are estradiol metabolites produced during folliculogenesis in the mammalian ovary. 2-Hydroxyestradiol (2-OHE₂) is one of the most abundant although its role remains unknown. The aim of this study is to investigate whether the presence of 2-OHE₂ during the germinal vesicle-to-metaphase II transition affects oocyte meiotic and preimplantation developmental competence. Mouse cumulus-oocyte complexes (COCs), isolated from fully grown antral follicles, were in vitro–matured (IVM) in the presence of 2-OHE₂ (0.1, 1, 10 or 100 nM) for 6 or 15 h; then, their meiotic and developmental competence was evaluated using a number of cytological quality markers. With the exception of the highest dose (100 nM), the addition of 2-OHE₂ to the IVM medium, did not alter, compared with untreated control, the frequency of oocytes that reached the MII stage. Instead, IVM in the presence of 1 nM 2-OHE₂ highly increased the rate of preimplantation development and blastocyst quality. To understand whether this positive effect could be attributed to the events occurring during meiosis resumption, we analysed a number of specific cytological quality markers of the asymmetric division, such as PB-I volume and position, presence and extension of the cortical F-actin cap, meiotic spindle shape and area, and microtubule organisation centre localisation. The results highlighted how the presence of 1 nM 2-OHE₂ significantly improved the overall cytological organisation required for a correct asymmetric division. Our results contribute a first step to acknowledge a potential role of this estradiol metabolite during the GV-to-MII transition, contributing to the acquisition of oocytes developmental competence.

Identification and characterization of putative ovarian lincRNAs in dairy goats treated for repeated estrous synchronization

The goal of this study was to identify and characterize effects of repeated estrous synchronization (ES) treatments on the regulation of ovarian intergenic long non-coding RNAs (lincRNAs) in dairy goats. Six does were randomly assigned to a group administered three ES treatment regimens separated by 2 weeks or to a group administered only one ES treatment regimen (control) at the same time as the third ES treatment in the does administered the three hormonal regimens for ES. The paired-end RNA Sequencing procedures were used to evaluate lincRNAs of ovarian tissues. A total of 134 lincRNAs were differentially abundant between the two treatment groups. Several target genes were annotated and were related to hormone activity, cellular response to hormone stimulus, response to hormone, female pregnancy, as well as regulation of hormone secretion. These genes were noticeably enriched in MAPK, Hippo, estrogen signaling pathways, oocyte meiosis, progesterone-mediated oocyte maturation, ovarian steroidogenesis as well as GnRH signaling pathways. According to the enriched GO terms and KEGG pathways of regulated genes, 13 differentially abundant lincRNAs could be promising candidates for regulating reproductive functions of female goats. Current results indicate that repeated treatments with gonadotropins affected hormone sensitivity, estrogen synthesis, and ovarian function. The results also indicated that when there was imposing of the three hormonal treatment regimens for ES, there were several lincRNAs that could contribute to dysregulation of several genes that are important for reproduction in dairy goats. Findings provide novel insights for further investigation of lncRNAs biological functions in goats.

Gene X environment: the cellular environment governs the transcriptional response to environmental chemicals

Background

An individual’s response to environmental exposures varies depending on their genotype, which has been termed the gene-environment interaction. The phenotype of cell exposed can also be a key determinant in the response to physiological cues, indicating that a cell-gene-environment interaction may exist. We investigated whether the cellular environment could alter the transcriptional response to environmental chemicals. Publicly available gene expression array data permitted a targeted comparison of the transcriptional response to a unique subclass of environmental chemicals that alter the activity of the estrogen receptor, xenoestrogens.

Results

Thirty xenoestrogens were included in the analysis, for which 426 human gene expression studies were identified. Comparisons were made for studies that met the predefined criteria for exposure length, concentration, and experimental replicates. The cellular response to the phytoestrogen genistein resulted in remarkably unique transcriptional profiles in breast, liver, and uterine cell-types. Analysis of gene regulatory networks and molecular pathways revealed that the cellular context mediated the activation or repression of functions important to cellular organization and survival, including opposing effects by genistein in breast vs. liver and uterine cell-types. When controlling for cell-type, xenoestrogens regulate unique gene networks and biological functions, despite belonging to the same class of environmental chemicals. Interestingly, the genetic sex of the cell-type also strongly influenced the transcriptional response to xenoestrogens in the liver, with only 22% of the genes significantly regulated by genistein common between male and female cells.

Conclusions

Our results demonstrate that the transcriptional response to environmental chemicals depends on a variety of factors, including the cellular context, the genetic sex of a cell, and the individual chemical. These findings highlight the importance of evaluating the impact of exposure across cell-types, as the effect is responsive to the cellular environment. These comparative genetic results support the concept of a cell-gene-environment interaction.

Genome-wide analysis and functional prediction of the estrogen-regulated transcriptional response in the mouse uterus†

The ovarian hormones estrogen and progesterone orchestrate the transcriptional programs required to direct functions of the uterus for initiation and maintenance of pregnancy. Estrogen, acting via estrogen receptor alpha, regulates gene expression by activating and repressing distinct genes involved in signaling pathways that regulate cellular and physiological responses including cell division, water influx, and immune cell recruitment. Historically, these transcriptional responses have been postulated to reflect a biphasic physiological response. In this study, we explored the transcriptional responses of the ovariectomized mouse uterus to 17β-estradiol (E2) by RNA-seq to obtain global expression profiles of protein-coding transcripts (mRNAs) and long noncoding RNAs (lncRNAs) following 0.5, 1, 2, and 6 hours of treatment. The E2-regulated mRNA and lncRNA expression profiles in the mouse uterus indicate an association between lncRNAs and mRNAs that regulate E2-driven pathways and reproductive phenotypes in the mouse. The transient E2-regulated transcriptome is reflected in the time-dependent shifting of biological processes regulated in the uterus in response to E2. Moreover, high expression of some conserved lncRNAs that are E2 regulated in the mouse uterus are predictive of low overall survival in endometrial carcinoma patients (e.g., H19, KCNQ1OT1, MIR17HG, and FTX). Collectively, this study (1) describes a genomic approach for identifying E2-regulated lncRNAs that may serve critical function in the uterus and (2) provides new insights into our understanding of the regulation of hormone-regulated transcriptional responses with implications in pregnancy and endometrial pathologies.

Estradiol/GPER affects the integrity of mammary duct-like structures in vitro

High estrogen concentration leads to an inflammatory reaction in the mammary gland tissue in vivo; however, the detailed mechanism underlying its specific effects on the breast duct has not been fully clarified. We used 3D-cultured MCF-10A acini as a breast duct model and demonstrated various deleterious effects of 17-β estradiol (E2), including the destruction of the basement membrane surrounding the acini, abnormal adhesion between cells, and cell death via apoptosis and pyroptosis. Moreover, we clarified the mechanism underlying these phenomena: E2 binds to GPER in MCF-10A cells and stimulates matrix metalloproteinase 3 (MMP-3) and interleukin-1β (IL-1β) secretion via JNK and p38 MAPK signaling pathways. IL-1β activates the IL-1R1 signaling pathway and induces continuous MMP-3 and IL-1β secretion. Collectively, our novel findings reveal an important molecular mechanism underlying the effects of E2 on the integrity of duct-like structures in vitro. Thus, E2 may act as a trigger for ductal carcinoma transition in situ.

The nuclear receptor seven up functions in adipocytes and oenocytes to control distinct steps of Drosophila oogenesis

Reproduction is intimately linked to the physiology of an organism. Nuclear receptors are widely expressed transcription factors that mediate the effects of many circulating molecules on physiology and reproduction. While multiple studies have focused on the roles of nuclear receptors intrinsically in the ovary, it remains largely unknown how the actions of nuclear receptors in peripheral tissues influence oogenesis. We identified the nuclear receptor encoded by svp as a novel regulator of oogenesis in adult Drosophila. Global somatic knockdown of svp reduces egg production by increasing GSC loss, death of early germline cysts, and degeneration of vitellogenic follicles. Tissue-specific knockdown experiments revealed that svp remotely controls these different steps of oogenesis through separate mechanisms involving distinct tissues. Specifically, adipocyte-specific svp knockdown impairs GSC maintenance and early germline cyst survival, whereas oenocyte-specific svp knockdown increases the death of vitellogenic follicles without any effects on GSCs or early cysts. These results illustrate that nuclear receptors can control reproduction through a variety of mechanisms involving peripheral tissues.

Inflammation, depression and cardiovascular disease in women: the role of the immune system across critical reproductive events

Women are at increased risk for developing depression and cardiovascular disease (CVD) across the lifespan and their comorbidity is associated with adverse outcomes that contribute significantly to rates of morbidity and mortality in women worldwide. Immune-system activity has been implicated in the etiology of both depression and CVD, but it is unclear how inflammation contributes to sex differences in this comorbidity. This narrative review provides an updated synthesis of research examining the association of inflammation with depression and CVD, and their comorbidity in women. Recent research provides evidence of pro-inflammatory states and sex differences associated with alterations in the hypothalamic–pituitary–adrenal axis, the renin–angiotensin–aldosterone system and the serotonin/kynurenine pathway, that likely contribute to the development of depression and CVD. Changes to inflammatory cytokines in relation to reproductive periods of hormonal fluctuation (i.e. the menstrual cycle, perinatal period and menopause) are highlighted and provide a greater understanding of the unique vulnerability women experience in developing both depressed mood and adverse cardiovascular events. Inflammatory biomarkers hold substantial promise when combined with a patient’s reproductive and mental health history to aid in the prediction, identification and treatment of the women most at risk for CVD and depression. However, more research is needed to improve our understanding of the mechanisms underlying inflammation in relation to their comorbidity, and how these findings can be translated to improve women’s health.

Estrogen-dependent downregulation of hypoxia-inducible factor (HIF)-2α in invasive breast cancer cells

The involvement of estrogen (E2) and hypoxia in tumor progression is well established. Hypoxia has been reported to activate and degrade estrogen receptor alpha (ERα) in breast cancer cells. Furthermore, E2 has been shown to regulate hypoxia-inducible factor (HIF)-1α protein, but its role in HIF-2α regulation remains largely unexplored. In this study, we found that both HIF-2α mRNA and protein were down-regulated in ER positive but not ER negative breast cancer cells upon treatment with E2. The analysis of 690 samples derived from 608 mixed and 82 triple-negative breast cancer patients revealed that high nuclear HIF-2α tumor levels are associated with a worse prognosis specifically in human epidermal growth factor receptor 2 (HER2) and hormone receptor positive patients. Consistently, ERα/HER2 positive breast cancer cells displayed less pronounced downregulation of HIF-2α by E2. Experiments using a histone deacetylase inhibitor indicate that the E2 mediated decrease in HIF-2α mRNA is due to transcriptional repression. A functional estrogen response element (ERE) was identified in the first intron of the gene encoding HIF-2α (EPAS1), suggesting transcriptional co-repressor recruitment by ERα. Our results demonstrate a novel modulation of HIF-2α in breast cancer cells, explaining the opposing regulation between HIF-1α and HIF-2α in hormone-responsive breast cancer.

The impact of combined oral contraceptives on ocular tissues: a review of ocular effects

The aim of this manuscript is to review the action and adverse effects of combined oral contraceptives (COCs) on ocular tissues. The percentage of unwanted pregnancies and the subsequent abortions make contraception crucial worldwide. Over 100 million women around the world use common contraceptive methods, including intrauterine devices, combined estrogen and progestin oral contraceptives, as well as progestin only preparations (oral contraceptives, implants or injections). COCs are widely used for contraception, but they are also indicated in menorrhagia, endometriosis, acne and hirsutism, fibroid uterus and premenstrual syndrome. However, they have been associated with high rates of cardiovascular events, venous thromboembolic disease, ischemic strokes and breast cancer. The incidence of COCs-related ocular complications is estimated to be 1 in 230 000, including dry eye symptoms, corneal edema, lens opacities and retinal neuro-ophthalmologic or vascular complications. We may infer that the serious ocular complications of COCs can be prevented by eliminating the estrogen dosage and choosing third-generation progestins. In any case, doctors should take into consideration the systemic and ocular history of the patients before selecting any method of contraception.

Characteristics, tissue-specific expression, and hormonal regulation of expression of tyrosine aminotransferase in the avian female reproductive tract

Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine to p-hydroxyphenylpyruvate. Accumulation of tyrosine in the body due to a genetic mutation in the TAT gene causes tyrosomia type II in humans. The TAT gene is regarded as a model for studying steroid-inducible factors regulating a variety of biological functions of TAT. However, little is known of the effects of estrogen on the expression of the TAT gene in chickens. Therefore, in the present study, we identified expression of the avian TAT gene in various organs. The results showed the TAT was detected predominantly in the liver and reproductive organs including testis, oviduct, and ovary. Specifically, TAT mRNA was expressed abundantly in the glandular and luminal epithelia of the oviducts in response to endogenous and exogenous estrogens which also induce dramatic morphological changes in the oviduct of chickens. In addition, target microRNAs of TAT (miR-1460, miR-1626-3p, miR-1690-5p, and miR-7442-3p) were found to modulate expression of the TAT gene. Especially, miR-1690-5p influenced TAT gene transcription by binding directly to its 3'-UTR region. Moreover, the expression of TAT was abundant in glandular epithelia of cancerous but not normal ovaries from laying hens. Taken together, our findings suggest that TAT plays an important role in the cytodifferentiation of oviducts in response to estrogen and in the progression of ovarian cancer in chickens.

Improved hematopoietic differentiation of human pluripotent stem cells via estrogen receptor signaling pathway

Background

Aside from its importance in reproduction, estrogen (E2) is known to regulate the proliferation and differentiation of hematopoietic stem cells in rodents. However, the regulatory role of E2 in human hematopoietic system has not been investigated. The purpose of this study is to investigate the effect of E2 on hematopoietic differentiation using human pluripotent stem cells (hPSCs).

Results

E2 improved hematopoietic differentiation of hPSCs via estrogen receptor alpha (ER-α)-dependent pathway. During hematopoietic differentiation of hPSCs, ER-α is persistently maintained and hematopoietic phenotypes (CD34 and CD45) were exclusively detected in ER-α positive cells. Interestingly, continuous E2 signaling is required to promote hematopoietic output from hPSCs. Supplementation of E2 or an ER-α selective agonist significantly increased the number of hemangioblasts and hematopoietic progenitors, and subsequent erythropoiesis, whereas ER-β selective agonist did not. Furthermore, ICI 182,780 (ER antagonist) completely abrogated the E2-induced hematopoietic augmentation. Not only from hPSCs but also from human umbilical cord bloods, does E2 signaling potentiate hematopoietic development, suggesting universal function of E2 on hematopoiesis.

Conclusions

Our study identifies E2 as positive regulator of human hematopoiesis and suggests that endocrine factors such as E2 influence the behavior of hematopoietic stem cells in various physiological conditions.

Electronic supplementary material

The online version of this article (doi:10.1186/s13578-016-0111-9) contains supplementary material, which is available to authorized users.

Multigenerational exposure to dietary zearalenone (ZEA), an estrogenic mycotoxin, affects puberty and reproduction in female mice

This study investigated potential cumulative effects of multiple pregnancy and multigenerational exposure to dietary ZEA (0, 0.8, 4, or 20ppm) on female puberty and reproduction in C57BL/6J mice. Multiple pregnancies did not significantly affect litter size or offspring puberty. Significant effects were observed in 20ppm ZEA-treated females: advanced puberty onset in F0, F1, and F2 generations; decreased implantation rate, pregnancy rate, and litter size, and increased pregnancy gap and gestation period in F1 and F2 generations; and reduced fertility index in F2 generation. F3 females from 0 and 20ppm groups were split into 0 or 20ppm ZEA diets at weaning, with advanced puberty onset seen in 0-20 and 20-20 groups and decreased implantation rate observed in 20-20 group. In summary, 20ppm dietary ZEA advanced puberty onset without obvious cumulative effect and impaired fertility with multigenerational cumulative effect, which could be partially alleviated upon exposure cessation.

Regeneration of spermatogenesis in a mouse model of azoospermia by follicle-stimulating hormone and oestradiol

Busulfan is a chemotherapeutic drug that induces sterility, azoospermia and testicular atrophy. To induce degeneration of spermatogenesis, we used different amounts of busulfan. Adult male C57Bl/6 mice were treated with 15, 30 and 45 mg kg(-1) of busulfan. After 5 weeks, animals had daily injections of 7.5 IU human follicle-stimulating hormone (hFSH) and 12.5 μg kg(-1) oestradiol benzoate (EB), separately or simultaneously. After this time, the animals were killed and blood samples were taken through cardiac puncture. Testes were used for histopathology experiments, DNA flow cytometry and RNA extraction for expression of c-kit and cyclin B1 genes. EB unlike FSH has induced stimulatory effects on spermatogenesis, increased the level of serum testosterone 2-fold and caused a 2-fold increase in the number of haploid cells. The result showed that hFSH with EB multiplied EB stimulatory effects on spermatogenesis up to four times. Expression of c-kit and cyclin B1 genes increased in EB and hFSH+EB groups. These findings suggest that EB regulates spermatogonial stem cells via hFSH. hFSH with EB had synergistic effect on regeneration of spermatogenesis.

Estrogen regulates JNK1 genomic localization to control gene expression and cell growth in breast cancer cells

Steroid hormone and MAPK signaling pathways functionally intersect, but the molecular mechanisms of this cross talk are unclear. Here, we demonstrate a functional convergence of the estrogen and c-Jun N-terminal kinase 1 (JNK1) signaling pathways at the genomic level in breast cancer cells. We find that JNK1 binds to many promoters across the genome. Although most of the JNK1-binding sites are constitutive, a subset is estrogen regulated (either induced on inhibited). At the estrogen-induced sites, estrogen receptor (ER)α is required for the binding of JNK1 by promoting its recruitment to estrogen response elements or other classes of DNA elements through a tethering mechanism, which in some cases involves activating protein-1. At estrogen-regulated promoters, JNK1 functions as a transcriptional coregulator of ERα in a manner that is dependent on its kinase activity. The convergence of ERα and JNK1 at target gene promoters regulates estrogen-dependent gene expression outcomes, as well as downstream estrogen-dependent cell growth responses. Analysis of existing gene expression profiles from breast cancer biopsies suggests a role for functional interplay between ERα and JNK1 in the progression and clinical outcome of breast cancers.

Pharmacology and clinical use of sex steroid hormone receptor modulators

Sex steroid receptors are ligand-triggered transcription factors. Oestrogen, progesterone and androgen receptors form, together with the glucocorticoid and mineralocorticoid receptors, a subgroup of the superfamily of nuclear receptors. They share a common mode of action, namely translating a hormone-i.e. a small-molecule signal-from outside to changes in gene expression and cell fate, and thereby represent "natural" pharmacological targets.For pharmacological therapy, these receptors have originally been addressed by hormones and synthetic hormone analogues in order to overcome pathologies related to deficiencies in the natural ligands. Another major use for female sex hormone receptor modulators is oral contraception, i.e. birth control.On the other side, blocking the activity of sex steroid receptors has become an established way to treat hormone-dependent malignancies, such as breast and prostate cancer.In this review, we will discuss how the experience gained from the classical pharmacology of these receptors and their molecular similarities led to new options for the treatment of gender-specific diseases and highlight recent progress in medicinal chemistry of sex hormone-modulating drugs.