Reproductive biology
Abstract
Successful implantation requires precise coordination of uterine epithelial receptivity, stromal decidualization, and immune homeostasis during a narrow peri-implantation window. Although retinoic acid (RA) signaling has been implicated in female reproduction, the endogenous and isoform-specific roles of retinoic acid receptors (RARs) remain poorly defined. Here, we combined isoform-specific genetic mouse models, transcriptomic profiling, and functional studies in mouse and human stromal cells to determine how RAR signaling regulates early pregnancy. We found that RARG is the dominant RAR isoform required for female fertility in mice, as its deletion severely impaired implantation, whereas combined loss of all RAR isoforms caused complete reproductive failure. RAR deficiency disrupted multiple sequential reproductive processes, including sperm transport and fertilization, suppression of uterine estrogen receptor activity, acquisition of stromal decidualization competence, and maintenance of uterine immune homeostasis. Transcriptomic analyses identified conserved epithelial and mesenchymal programs altered across independent RAR-deficient mouse models and revealed significant overlap with endometrial gene signatures from women with recurrent implantation failure. In human endometrial stromal cells, suppression of the RARA isoform consistently disrupted decidualization across three independent primary cell lines and an immortalized cell model. Together, these findings identify RAR signaling as a critical regulator of early pregnancy and reveal conserved, isoform-specific functions required for early pregnancy.
Authors
Yan Yin, Emily Y. So, Eliana Wolf, Vivian Robles Pinos, Meade Haller, Renjie Shang, Sylvia C. Hewitt, Alex Tak, Brent M. Bany, David Y. Chen, Mengcheng Shen, Francesco J. DeMayo, Liang Ma
Abstract
Insulin resistance (IR) has emerged as a risk factor for lactation insufficiency and delays the onset of milk secretion after childbirth, termed secretory activation (SA). This may cause inadequate infant weight gain and early breastfeeding cessation. However, the mechanisms underlying delayed SA in insulin resistant women are unknown. To investigate this, we characterized the mammary transcriptomes and IR-related hormones of 75 breastfeeding women with healthy term infants during postpartum days 1-5. Participants were divided into IR tertiles based on plasma leptin-to-adiponectin ratio measurements. Those in the highest tertile had later SA onset with greater neonatal weight loss during postpartum days 1-5. Transcriptomic analysis on postpartum day 2 (n=4 high IR vs. n=8 low IR participants) showed transient suppression of mammary insulin and prolactin signaling genes, increased pro-inflammatory gene expression and altered expression of >200 mammary mitochondrial genes. These alterations were absent on postpartum days 3-5. Cultured mammary epithelial cells (MECs) treated with insulin showed upregulation of prolactin signaling and oxidative phosphorylation (OXPHOS) genes, with imaging and bioenergetic studies demonstrating that insulin promotes mitochondrial biogenesis and OXPHOS. Thus, our findings delineate roles for insulin in mammary bioenergetics and highlight mitochondrial dysfunction as a mechanism for delayed SA in insulin resistant women.
Authors
Xin Meng, Taha Elajnaf, Hussam Rostom, Michelle Ma, Annalee Furst, Bryony R. Davies, Isabella R. Honess, Gaurav Pandey, Isadora C. Furigo, Craig L. Doig, Jayne F. Martin Carli, Rajesh V. Thakker, Lars Bode, Kelsey E. Johnson, Fadil M. Hannan
Abstract
Polyendocrine metabolic ovarian syndrome (PMOS), formerly known as polycystic ovary syndrome (PCOS), is the most common endocrine disorder in women and is closely associated with complex diseases such as cardiovascular disease and type 2 diabetes. However, the mechanistic links between PMOS and its comorbidities remain poorly understood. Here, we present an integrative systems genetics platform that leverages genetic diversity in both mice and humans to dissect the drivers of PMOS and its associated complications. This framework uncovers conserved genetic and environmental factors underlying PMOS, identifies susceptible cell types and organs, and elucidates mechanisms linking PMOS to subsequent pathologies. For instance, we show that increased ovarian area contributes to both PMOS susceptibility and ovarian cancer progression, while specific ovary–heart signaling circuits modulate cardiac function with aging. We further identify ovarian SF3B1-mediated alternative splicing as a key mechanistic link between PMOS and metabolic traits. Pharmacologic inhibition of SF3B1 in mice reduced circulating testosterone, insulin and glucose levels, as well as fat mass expansion. Transcriptomics analysis of ovaries from mice and experiments using human cell lines localized these effects to exon skipping events in granulosa cells. Together, this study offers a mechanistic framework for modeling the diversity of PMOS pathologies and uncovers SF3B1-mediated splicing as a link between ovary function and systemic metabolism.
Authors
Christy M. Nguyen, Leandro M. Velez, Youngseo Cheon, Cimone L. Jackson, Casey D. Johnson, Ian Tamburini, Mingqi Zhou, Erik Alvstad, Isoo Yoon, Farheen Dustagheer, Marie Li, Tvisha Gujjarlapudi, Kaitlene Ofilan, Neha Mishra, Evan G. Williams, Danica Kwan, Carlos H. Viesi, Naveena Ujagar, David G. Ashbrook, Alistair Senior, Marin E. Nelson, Nicholas R. Pannunzio, Selma Masri, Evgeny Kvon, Grant MacGregor, Cholsoon Jang, Vittorio Sebastiano, Minji Byun, Changrui Xiao, Alexander S. Kauffman, Robert W. Williams, David E. James, Ivan Marazzi, Dequina Nicholas, Marcus Seldin
Abstract
During early pregnancy, maternal blood surrounds the embryo before the placenta is fully developed, requiring tight regulation of maternal blood flow into the placental vasculature. We identify placental microthrombi (PMTs) as essential structures guiding this process. PMTs contain platelets, coagulation factors, and complement proteins, and their formation depends on maternal platelet activation by thrombin through the protease-activated receptor PAR4 (F2rl3). Deficiency of PAR4 abolished PMTs and caused excessive bleeding at the implantation site. C3 deficiency also led to increased bleeding events, indicating that complement activation contributes to thrombosis in the placental circulation. Conversely, dysregulated complement activation in CMP-sialic acid synthase-deficient (Cmas-/-) mice led to widespread thrombosis and failed placental development. Strikingly, platelet activation via PAR4 was necessary to localize complement activation to trophoblast surfaces, thereby coupling coagulation and complement in PMT formation. Depletion of maternal platelets mitigated complement-driven thromboinflammation in Cmas-/- pregnancies, restoring placental growth. These findings uncover a critical cooperation between platelets, coagulation, and complement in establishing maternal blood flow to the placenta. Successful pregnancy therefore requires not only activation but also tight regulation of these systems to balance necessary PMT formation with the prevention of pathological thrombosis.
Authors
Arno Smid, Lisa Schumann, Olga Oleshko, Ulrike Peters-Bernard, Kerstin Flächsig-Schulz, Melissa Whitehead, Emma Arndt, Korbinian Brand, Sonja Werwitzke, Andreas Klos, Bryan Paul Morgan, Wioleta M. Zelek, Andreas Tiede, Markus Abeln
Abstract
Defective endometrial decidualization is one major cause of female infertility, yet the underlying mechanisms remain elusive. Here, we identified that protein arginine methyltransferase 5 (PRMT5) which was upregulated during decidualization and by progesterone stimulation, is markedly down-regulated in the endometria of patients with recurrent implantation failure (RIF), along with a global reduction of symmetric dimethylarginine (sDMA). Uterine stromal-specific ablation of Prmt5 in mouse severely impaired decidualization leading to infertility. A multi‑omics analysis in human endometrial stromal cells (EnSCs) revealed that PRMT5 promoted decidualization primarily by catalyzing sDMA at arginine 346 (R346) of the orphan nuclear receptor Nur77, which directs its proper chromatin occupancy. Targeting the PRMT5-Nur77 methylation axis, we designed a peptide, Pep‑Nur77-R346K, which rescued the decidualization of multiple preclinical models: PRMT5 deficient human EnSCs, both genetic knockout (Prmt5d/d) and pharmacologically inhibited mouse models, an estrogen deficient mouse model, and, more importantly, the primary RIF EnSCs. In a retrospective cohort of 114 participants, the correlated reductions of endometrial PRMT5/Nur77-R346me2s was confirmed, which demonstrated robust predictive value for pregnancy outcome. Our work establishes the PRMT5‑Nur77 methylation axis as a key regulator of endometrial receptivity, and highlights both a novel diagnostic biomarker and a peptide‑based therapeutic potential for fertility.
Authors
Zhiwen Cao, Xinyu Cai, Jie Mei, Na Kong, Yang Liu, Xiaoyue Shen, Min Wu, Xin Zhen, Jianxin Sun, Rong Li, Ruiwei Jiang, Haixiang Sun, Guijun Yan
Abstract
BACKGROUND. In female murine models, one source of inflammation is a menopause-related increase in gut permeability. We examined whether the menopause transition (MT) in women is associated with an increase in markers of gut epithelial dysfunction and gut microbial product translocation, signals of compromised gut epithelial barrier integrity. METHODS. In 964 women, we measured markers of gut epithelial dysfunction (fatty acid binding protein 2, FABP2) and gut microbial antigen translocation (soluble CD14, sCD14) using sera collected before, during and after the MT. Multivariable mixed effects regressions fit piece-wise linear models to repeated FABP2 or sCD14 measures relative to time from final menstrual period (FMP). Covariates were age at FMP, race/ethnicity, and BMI. RESULTS. FABP2 and sCD14 did not change significantly until 2.5 years pre-FMP. At that point, FABP2 began rising; sCD14 began increasing 6 months later. FABP2 and sCD14 peaked 6 and 6.5 years post-FMP, respectively; subsequent levels remained stable. During the ~9-year interval of MT-related gain in gut barrier compromise markers, annual FABP2 and sCD14 increases were 2.6% (95% CI: 1.7 to 3.4%) and 0.8% (95% CI: 0.6 to 1.1%), respectively, among white women with sample-average BMI and age at FMP. FABP2 and sCD14 change rates did not differ significantly by race/ethnicity, BMI, or age at FMP. CONCLUSIONS. The MT is associated with a rise in markers of compromised gut barrier integrity, suggesting that this pathway of inflammation, previously described in animal models, occurs in humans. FUNDING. NIH U01NR004061, U01AG012505, U01AG012535, U01AG012531, U01AG012539, U01AG012546, U01AG012553, U01AG012554, U01AG012495, 5R01AR081794.
Authors
Albert Shieh, Marta Epeldegui, Arun S. Karlamangla, Rheinallt Jones, Roberto Pacifici, Gail A. Greendale
Abstract
Reproductive aging is characterized by a progressive decline of reproductive function, with broad implications for overall health and longevity. Environmental factors, including assisted reproductive technologies (ART), can accelerate reproductive aging by promoting premature ovarian failure in females. In vitro fertilization (IVF) though widely used and generally considered safe, has been associated with lasting effects on offspring health. Using a mouse model that closely approximates human IVF, we demonstrated that IVF accelerates reproductive aging in female offspring by inducing premature ovarian failure. IVF-conceived females exhibited altered ovarian function, reduced follicle reserve, disrupted endocrine profiles, and transcriptomic and epigenetic changes consistent with premature reproductive decline. These findings reveal long-term consequences of IVF on female reproductive health and highlight the need to understand how early-life interventions influence reproductive longevity.
Authors
Eric A. Rhon-Calderon, Cassidy N. Hemphill, Alexandra J. Savage, Ana Domingo-Muelas, Zhengfeng Liu, Christopher J. Krapp, Laren Riesche, Nicolas Plachta, Richard M. Schultz, Marisa S. Bartolomei
Abstract
Klinefelter syndrome (KS), the most common sex chromosome aneuploidy (affecting approximately 1 in 650 live male births), causes severe infertility. The extra X chromosome can impair the development of fetal germ cells, but its effects on somatic cells, especially the Leydig cells, are still not well known. We performed single-cell transcriptome analysis of fetal KS and control testicular cells, and found that two clusters of KS Sertoli cells with the XIST-negative cluster showing distinct gene expression pattern and abnormally increased G2/M ratio. Fetal KS Leydig cells showed increased proliferation and immature differentiation with high level of MAPK signaling pathway and X-linked EIF1AX. Inhibition of MAPK signaling partially rescued overproliferation and defective differentiation and androgen secretion in KS Leydig cells, while overexpression of EIF1AX recapitulated the phenotype of increased proliferation and decline in testosterone synthesis capacity in the Leydig cell line. These findings revealed the early pathological mechanisms of KS somatic cells, and lay the groundwork for developing novel early intervention strategies.
Authors
Tong Yan, Guancheng Chen, Jie Zhang, Wenjing Jia, Nan Lu, Shuping Jin, Haotian Zhang, Yichen Zhao, Lu Jiang, Jing Wu, Qing Liu, Chenghao Situ, Hui Zhu, Yan Li, Quan Wang, Xiaoyu Yang, Chao Qin, Xiaofeng Song, Qing Cheng, Xuejiang Guo
Abstract
This study investigated how chronic pelvic pain (CPP) develops using rhesus macaques with naturally occurring endometriosis and a multiple-lesion induction mouse model (MIM), as repeated retrograde menstruation is considered an underlying mechanism of endometriosis pathogenesis. MIM increased lesion numbers and elevated hypersensitivity. Elevated persistent glial cell activation was observed across multiple brain regions and/or spinal cords in MIM and rhesus macaques. Elevated TRPV1, SP, and CGRP expressions in the dorsal root ganglia (DRG) were persistent in MIM. MIM induced the severe disappearance of TIM4hi MHCIIlo residential macrophages and an influx of increased pro-inflammatory TIM4lo MHCIIhi macrophages in the peritoneal cavity. Cytokine levels were persistently elevated in MIM. Furthermore, dienogest (a synthetic progestin) and fingolimod (a selective immunosuppressor) reduced hyperalgesia and neuroinflammation. Our results indicate that recurrent retrograde menstruation can be a peripheral stimulus that induces nociceptive pain and creates a composite chronic inflammatory stimulus, leading to neuroinflammation and sensitization of the central nervous system. The circuits of neuroplasticity and stimulation of peripheral organs via a feedback loop of neuroinflammation may mediate widespread endometriosis-associated CPP. These findings in mice were further supported by results from the spontaneously developed advanced endometriosis in rhesus macaques via recurrent retrograde menstruation.
Authors
Madeleine E. Harvey, Mingxin Shi, Yeongseok Oh, Taylor M. Page, Debra A. Mitchell, Addie Luo, Ov D. Slayden, James A. MacLean, Anjali Sharma, Kanako Hayashi
Abstract
Estrogen is a critical regulator of endometrial health. Aberrant estrogen stimulation can result in infertility, endometrial cancer, and endometriosis. Here, we identified Zinc Finger MIZ-Type Containing 1 (Zmiz1) as a coregulator of uterine estrogen signaling. ZMIZ1 is colocalized with an estrogen receptor α–binding (ESR1-binding) super enhancer. ZMIZ1 mutations are found in endometrial cancer and its RNA levels trend toward reduction in endometrium of patients with endometriosis. ZMIZ1 is dynamically expressed in human endometrial tissues during the menstrual cycle. Disrupting ZMIZ1 in cultured human endometrial stromal cells resulted in impaired cell proliferation and decidual differentiation. Ablation of Zmiz1 using the PgrCre mouse (Zmiz1d/d) resulted in infertility and accelerated age-dependent uterine fibrosis. Zmiz1d/d mice showed reduced ovulation and progesterone levels while maintaining normal serum prolactin during pregnancy. Uteri of Zmiz1d/d mice were unable to undergo a hormonally induced decidual response, had decreased expression of stromal progesterone receptor (PGR) and decreased stromal and epithelial cell proliferation. Analysis of the transcriptome of Zmiz1d/d mouse uteri showed decreased E2F, CCNA2, and FOXM1 signaling. Challenging ovariectomized Zmiz1d/d mice with estrogen resulted in a decreased amplitude of some estrogen-regulated gene responses. Our findings demonstrate the importance of ZMIZ1 as an ESR1 coregulator in uterine biology and pathology.
Authors
Sylvia C. Hewitt, Frank Orellana, Ryan M. Marquardt, MyeongJin Yi, Cynthia J. Willson, Mark Y. Chiang, Yong Song, Goutham Venkata Naga Davuluri, Christopher Day, Ramakrishna Kommagani, Joseph Rodriguez, Asgerally T. Fazleabas, John P. Lydon, Francesco J. DeMayo
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ISSN: 0021-9738 (print), 1558-8238 (online)