Naïve human pluripotent stem cells (hPSCs) provide a unique experimental platform of cell fate decisions during pre-implantation development, but their lineage potential remains incompletely characterized. As naïve hPSCs share transcriptional and epigenomic signatures with trophoblast cells, it has been proposed that the naïve state may have enhanced predisposition for differentiation along this extraembryonic lineage. Here we examined the trophoblast potential of isogenic naïve and primed hPSCs. We found that naïve hPSCs can directly give rise to human trophoblast stem cells (hTSCs) and undergo further differentiation into both extravillous and syncytiotrophoblast. In contrast, primed hPSCs do not support hTSC derivation, but give rise to non-self-renewing cytotrophoblasts in response to BMP4. Global transcriptome and chromatin accessibility analyses indicate that hTSCs derived from naïve hPSCs are similar to blastocyst-derived hTSCs and acquire features of post-implantation trophectoderm. The derivation of hTSCs from naïve hPSCs will enable elucidation of early mechanisms that govern normal human trophoblast development and associated pathologies.

Does altering gut microbiota with antibiotic treatment have any impact on endometriosis progression? Antibiotic therapy reduces endometriosis progression in mice, possibly by reducing specific gut bacteria. Endometriosis, a chronic condition causing abdominal pain and infertility, afflicts up to 10% of women between the ages of 25 and 40, ~5 million women in the USA. Current treatment strategies, including hormone therapy and surgery, have significant side effects and do not prevent recurrences. We have little understanding of why some women develop endometriosis and others do not. Mice were treated with broad-spectrum antibiotics or metronidazole, subjected to surgically-induced endometriosis and assayed after 21 days. The volumes and weights of endometriotic lesions and histological signatures were analysed. Proliferation and inflammation in lesions were assessed by counting cells that were positive for the proliferation marker Ki-67 and the macrophage marker Iba1, respectively. Differences in faecal bacterial composition were assessed in mice with and without endometriosis, and faecal microbiota transfer studies were performed. In mice treated with broad-spectrum antibiotics (vancomycin, neomycin, metronidazole and ampicillin), endometriotic lesions were significantly smaller (~ 5-fold; P < 0.01) with fewer proliferating cells (P < 0.001) than those in mice treated with vehicle. Additionally, inflammatory responses, as measured by the macrophage marker Iba1 in lesions and IL-1β, TNF-α, IL-6 and TGF-β1 in peritoneal fluid, were significantly reduced in mice treated with broad-spectrum antibiotics (P < 0.05). In mice treated with metronidazole only, but not in those treated with neomycin, ectopic lesions were significantly (P < 0.001) smaller in volume than those from vehicle-treated mice. Finally, oral gavage of faeces from mice with endometriosis restored the endometriotic lesion growth and inflammation (P < 0.05 and P < 0.01, respectively) in metronidazole-treated mice. N/A. These findings are from a mouse model of surgically-induced endometriosis. Further studies are needed to determine the mechanism by which gut bacteria promote inflammation, identify bacterial genera or species that promote disease progression and assess the translatability of these findings to humans. Our findings suggest that gut bacteria promote endometriosis progression in mice. This finding if translated to humans, could aid in the development of improved diagnostic tools and personalised treatment strategies. This work was funded, in part, by: a National Institutes of Health (NIH)/ National Institute of Child Health and Human Development (NICHD) grant (R00HD080742) to RK; Washington University School of Medicine start-up funds to RK; an Endometriosis Foundation of America Research Award to R.K.; and an NIH/NICHD grant (R01HD091218) to IUM. The authors report no conflict of interest.

Progesterone (P4) signaling through its nuclear transcription factor, the progesterone receptor (PR), is essential for normal uterine function. Although deregulation of PR-mediated signaling is known to underscore uterine dysfunction and a number of endometrial pathologies, the early molecular mechanisms of this deregulation are unclear. To address this issue, we have defined the genome-wide PR cistrome in the murine uterus using chromatin immunoprecipitation (ChIP) followed by massively parallel sequencing (ChIP-seq). In uteri of ovariectomized mice, we identified 6367 PR-binding sites in the absence of P4 ligand; however, this number increased at nearly 3-fold (18,432) after acute P4 exposure. Sequence analysis revealed that approximately 73% of these binding sites contain a progesterone response element or a half-site motif recognized by the PR. Many previously identified P4 target genes known to regulate uterine function were found to contain PR-binding sites, confirming the validity of our methodology. Interestingly, when the ChIP-seq data were coupled with our microarray expression data, we identified a novel regulatory role for uterine P4 in circadian rhythm gene expression, thereby uncovering a hitherto unexpected new circadian biology for P4 in this tissue. Further mining of the ChIP-seq data revealed Sox17 as a direct transcriptional PR target gene in the uterus. As a member of the Sox transcription factor family, Sox17 represents a potentially novel mediator of PR action in the murine uterus. Collectively, our first line of analysis of the uterine PR cistrome provides the first insights into the early molecular mechanisms that underpin normal uterine responsiveness to acute P4 exposure. Future analysis promises to reveal the PR interactome and, in turn, potential therapeutic targets for the diagnosis and/or treatment of endometrial dysfunction.

The gut microbiome is considered an endocrine organ that can influence distant organs and associated biological pathways. Recent advances suggest that gut microbial homeostasis is essential for reproductive health and that perturbations in the gut microbiota can lead to reproductive pathologies. This review provides an updated overview of the relationship between the gut microbiome and female reproductive diseases. Specifically, we highlight the most recent findings on the gut microbiome in gynecological pathologies including polycystic ovarian syndrome, endometriosis, and endometrial cancer. Most studies revealed associations between altered gut microbial compositions and these reproductive diseases, though few have suggested cause–effect relationships. Future studies should focus on determining the molecular mechanisms underlying associations between gut microbiota and reproductive diseases. Understanding this bidirectional relationship could lead to the development of novel and effective strategies to prevent, diagnose, and treat female reproductive organ-related diseases.

Decidualization is a complex process involving cellular proliferation and differentiation of the endometrial stroma that is required to establish and support pregnancy. Progesterone acting via its nuclear receptor, the progesterone receptor (PGR), is a critical regulator of decidualization and is known to interact with certain members of the activator protein-1 (AP-1) family in the regulation of transcription. In this study, we identified the cistrome and transcriptome of PGR and identified the AP-1 factors FOSL2 and JUN to be regulated by PGR and important in the decidualization process. Direct targets of PGR were identified by integrating gene expression data from RNA sequencing with the whole-genome binding profile of PGR determined by chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) in primary human endometrial stromal cells exposed to 17β-estradiol, medroxyprogesterone acetate, and cAMP to promote in vitro decidualization. Ablation of FOSL2 and JUN attenuates the induction of 2 decidual marker genes, IGFBP1 and PRL. ChIP-seq analysis of genomic binding revealed that FOSL2 is bound in proximity to 8586 distinct genes, including nearly 80% of genes bound by PGR. A comprehensive assessment of the PGR-dependent decidual transcriptome integrated with the genomic binding of PGR identified FOSL2 as a potentially important transcriptional coregulator of PGR via direct interaction with regulatory regions of genes actively regulated during decidualization.

Worldwide, ∼196 million are afflicted with endometriosis, a painful disease in which endometrial tissue implants and proliferates on abdominal peritoneal surfaces. Theories on the origin of endometriosis remained inconclusive. Whereas up to 90% of women experience retrograde menstruation, only 10% develop endometriosis, suggesting that factors that alter peritoneal environment might contribute to endometriosis. Herein, we report that whereas some gut bacteria promote endometriosis, others protect against endometriosis by fermenting fiber to produce short-chain fatty acids. Specifically, we found that altered gut microbiota drives endometriotic lesion growth and feces from mice with endometriosis contained less of short-chain fatty acid and n-butyrate than feces from mice without endometriosis. Treatment with n-butyrate reduced growth of both mouse endometriotic lesions and human endometriotic lesions in a pre-clinical mouse model. Mechanistic studies revealed that n-butyrate inhibited human endometriotic cell survival and lesion growth through G-protein–coupled receptors, histone deacetylases, and a GTPase activating protein, RAP1GAP. Our findings will enable future studies aimed at developing diagnostic tests, gut bacteria metabolites and treatment strategies, dietary supplements, n-butyrate analogs, or probiotics for endometriosis.