Dysregulation of the Anti-Müllerian Hormone System by Steroids in Women With Polycystic Ovary Syndrome

Elevated IGFBP7 expression in follicular granulosa cells promotes PCOS pathogenesis

Polycystic ovary syndrome (PCOS) can result in female infertility, menstrual irregularities, metabolic disturbances, hormonal imbalances, and significantly impact the reproductive health of women of childbearing age. Hyperandrogenism and insulin resistance are typical primary endocrine features of PCOS, which are also regarded as its core pathogenesis. In this study, IGFBP7 expression in granulosa cells (GCs) from women with and without PCOS was analyzed using bulk RNA-seq. A PCOS-like mouse model was constructed using dehydroepiandrosterone in IGFBP7 knockout and wild-type mice to explore the role of IGFBP7 in PCOS. Primary GCs from mice were cultured and transfected with IGFBP7 overexpression plasmid and siRNA fragments. Proliferation, apoptosis, and steroid hormone levels were measured to investigate the effects of IGFBP7 on granulosa cells. IGFBP7 expression was found to be elevated in patients with PCOS. Following IGFBP7 knockdown in mouse GC, there was a significant increase in GC proliferation, a decrease in GC apoptosis, and a notable decrease in testosterone secretion by GC. Conversely, overexpression of IGFBP7 in mouse granulosa cells significantly inhibited GC proliferation, significantly increased GC apoptosis, and led to a marked increase in testosterone secretion by GCs. With mouse model, a reduction in PCOS symptoms in mice after IGFBP7 deletion was observed. Elevated IGFBP7 expression in PCOS granulosa cells may induce apoptosis, hinder insulin signaling, and enhance androgen synthesis. These insights offer novel avenues for understanding and treating PCOS.

Downregulation of FASN in granulosa cells and its impact on ovulatory dysfunction in PCOS

BACKGROUND

Polycystic ovary syndrome (PCOS) is a complicated endocrinological and anovulatory disorder in women. Mice exposed to dihydrotestosterone (DHT) exhibit a PCOS-like phenotype characterized by abnormal steroid hormone production and ovulation dysfunction. The present investigation aims to identify overlapping genes expressed in PCOS patients and a PCOS mouse model induced by DHT and to examine the function of key genes fatty acid synthase (FASN) in hormone production and ovulation dysfunction.

RESULTS

We examined 5 datasets of high-throughput mRNA transcription from the Gene Expression Omnibus (GEO) database, including 4 datasets from individuals with PCOS and 1 dataset from a DHT-induced mouse model. GO and KEGG enrichment analyses revealed these differentially expressed genes (DEGs) are primarily involved in ovarian steroidogenesis and fatty acid metabolism. The PPI network identified 12 hub genes. qRT-PCR verification in human granulosa cells showed differential expression of FASN, SCARB1, FABP5, RIMS2, and RAPGEF4 in PCOS patients (p < 0.05). FASN was downregulated in the granulosa cells (GCs) of PCOS patients (p < 0.05). FASN depletion reduced KGN cell proliferation (p < 0.001), decreased progesterone secretion (p < 0.05), and increased estradiol secretion (p < 0.05). Downregulation of FASN inhibited ovulation by suppressing ERK1/2 phosphorylation and the expression of C/EBPα and C/EBPβ. Lentivirus-mediated FASN downregulation in rat ovaries for one and four weeks impaired the super ovulatory response, reducing oocyte retrieval, estrous cycle, secretion of estrogen and progesterone, and luteinization.

CONCLUSIONS

Our results provide new insights into PCOS pathogenesis and suggest that FASN could be a promising target for treating abnormal steroid hormone production and impaired ovulation in PCOS.

A diagnostic model for polycystic ovary syndrome based on machine learning

Diagnosis of polycystic ovary syndrome remains a challenge. In this study, we propose constructing a diagnostic model of polycystic ovary syndrome by combining anti-Müllerian hormone with steroid hormones and oestrogens, with the aim of providing more bases and auxiliary means for the diagnosis of this disease. 1. Eighty-four samples from patients who were diagnosed with polycystic ovary syndrome at the First Affiliated Hospital of Zhejiang Chinese Medical University from May 2023 to November 2023 were collected as the case group, and 75 samples from the healthy population of the Health Screening Centre of the First Affiliated Hospital of Zhejiang Chinese Medical University during the same period were collected as the control group. 2. General information (including age, BMI, family history, medication history, etc.) and sex hormone data (including luteinising hormone, follicle stimulating hormone, prolactin, estradiol, testosterone, etc.) were collected from all study subjects. AMH and steroid hormone tests were performed on serum collected from all study subjects. 3. The data of 10 case groups and 10 control groups were randomly selected as validation set data, and the rest of the data were included in the model construction. The acquired data were screened for variables, a classification model based on a machine learning algorithm was constructed, and the constructed model was evaluated and validated for diagnostic efficacy. Ultimately, a total of 8 variables were screened and included in the subsequent model construction, namely LH, LH/FSH, E2, PRL, T, AMH, AD, and COR, with AMH having the highest diagnostic potential among all the variables included in the model. A total of five machine learning models were constructed, the logistic classification model has the best overall performance, and the support vector machine has the weakest overall performance. The validation set has an AUC of 0.86 for the model. In this study, five classification models based on machine learning algorithms were successfully constructed. Combining the evaluation metrics of each model performance, we concluded that the logistic classification model had the best performance capability in our study. However, since this study is a single-center small sample size study, some metabolic features of PCOS may be overlooked, and, as the validation set data in this study come from the same center as the modelling data, the validation results may have several limitations, so it is still necessary to expand the sample size and collect multicenter data to establish an external validation dataset to further improve the study.

Loureirin B Reduces Insulin Resistance and Chronic Inflammation in a Rat Model of Polycystic Ovary Syndrome by Upregulating GPR120 and Activating the LKB1/AMPK Signaling Pathway

Polycystic ovary yndrome (PCOS) is a common metabolic disorder in women, which is usually associated with insulin resistance (IR) and chronic inflammation. Loureirin B (LrB) can effectively improve insulin resistance and alleviate chronic inflammation, and in order to investigate the therapeutic effect of LrB on polycystic ovary syndrome with insulin resistance (PCOS-IR), we conducted animal experiments. A PCOS-IR rat model was established by feeding a high-fat diet combined with letrozole (1 mg/kg·d for 21 days). The rats were treated with the GPR120 agonists TUG-891 and LrB for 4 weeks. Biochemical parameters (fasting blood glucose, total cholesterol, triglycerides, high- and low-density lipoprotein), hormone levels (serum insulin, E2, T, LH, and FSH), and inflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-18) were analyzed. Histopathological analyses of ovaries were performed using hematoxylin/eosin (H&E) staining. Real-time PCR and western blotting were used to assess GPR120, NLRP3, and caspase-1 expression in ovaries, and immunohistochemistry was used to evaluate LKB1 and AMPK protein expression. LrB reduced body weight, Lee's index, ovarian index, ovarian area, and volume in PCOS-IR rats. It lowered fasting blood glucose, serum insulin, and HOMA-IR. LrB decreased total serum cholesterol, triglyceride, and LDL levels and increased HDL levels. It reduced serum T, LH, and LH/FSH and raised serum E2 and FSH levels. LrB downregulated the mRNA and protein expression levels of NLRP3 and Caspase-1, increased the protein and mRNA expression levels of GPR120 in rat ovaries, and increased LKB1 and AMPK protein expression in ovaries, ameliorating ovarian histopathological changes in PCOS-IR rats. Taken together, LrB upregulated GPR120, LKB1, and AMPK protein expression, downregulated NLRP3 and Caspase-1 protein expression, reduced insulin resistance and chronic inflammation, and ameliorated histopathological changes in ovarian tissues in PCOS rats, suggesting its potential as a treatment for PCOS.

The Cardiometabolic Risk in Women with Polycystic Ovarian Syndrome (PCOS): From Pathophysiology to Diagnosis and Treatment

Polycystic Ovarian Syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive age, with significant variations in presentation characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphology. Beyond reproductive health, it may also pose crucial long-term cardiometabolic risks, especially for women with specific types of PCOS, contributing to early subclinical cardiovascular atherosclerotic alterations such as endothelial dysfunction, increased arterial stiffness, and coronary artery calcium levels, respectively. Moreover, the precise relationship between clinical cardiovascular disease (CVD) and PCOS remains debated, with studies demonstrating an elevated risk while others report no significant association. This review investigates the pathophysiology of PCOS, focusing on insulin resistance and its link to subclinical and clinical cardiovascular disease. Diagnostic challenges and novel management strategies, including lifestyle interventions, medications like metformin and glucagon-like peptide-1 receptor agonists (GLP-1RAs), hormonal contraceptives, and bariatric surgery, are further discussed. Recognizing the cardiometabolic risks associated with PCOS, a comprehensive approach and early intervention should address both the reproductive and cardiometabolic dimensions of the syndrome.

Role of the AMP-Activated Protein Kinase in the Pathogenesis of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a complex disorder characterized by elevated androgen levels, menstrual irregularities, and polycystic morphology of the ovaries. Affecting 6-10% of women in childbearing age, PCOS is a leading cause of infertility worldwide. In recent years, there has been a growing acknowledgment of the involvement of adenosine monophosphate-activated protein kinase (AMPK) in the development of polycystic ovary syndrome (PCOS). The expression of AMPK is diminished in polycystic ovaries, and when AMPK is silenced in human granulosa cells, there is a rise in the expression of steroidogenic enzymes, resulting in increased production of estradiol and progesterone. Additionally, in mouse models, the inhibiting AMPK intensifies the polycystic appearance of ovaries and impairs the process of ovulation. Moreover, it has been shown that AMPK activators like metformin and resveratrol ameliorate PCOS associated signs and symptoms in experimental and clinical studies. These findings, collectively, indicate the key role of AMPK in the pathogenesis of PCOS. Understanding the role of AMPK in PCOS will offer rewarding information on details of PCOS pathogenesis and will provide novel more specific therapeutic approaches. The present review summarizes the latest findings regarding the role of AMPK in PCOS obtained in experimental and clinical studies.

Endoplasmic reticulum stress-mediated ferroptosis in granulosa cells contributes to follicular dysfunction of polycystic ovary syndrome driven by hyperandrogenism

RESEARCH QUESTION

Does hyperandrogenaemia affect the function of ovarian granulosa cells by activating ferroptosis, and could this process be regulated by endoplasmic reticulum stress?

DESIGN

Levels of ferroptosis and endoplasmic reticulum stress in granulosa cells were detected in women with and without polycystic ovary syndrome (PCOS) undergoing IVF. Ferroptosis and endoplasmic reticulum stress levels of ovarian tissue and follicle development were detected in control mice and PCOS-like mice models, induced by dehydroepiandrosterone. An in-vitro PCOS model of KGN cells was constructed with testosterone and ferroptosis inhibitor Fer-1. Endoplasmic reticulum stress inhibitor, tauroursodeoxycholate (TUDCA), determined the potential mechanism associated with excessive induction of ferroptosis in granulosa cells related to PCOS, and levels of ferroptosis and endoplasmic reticulum stress were detected.

RESULTS

Activation of ferroptosis and endoplasmic reticulum stress occurred in granulosa cells of women with PCOS and the varies of PCOS-like mice. The findings in KGN cells demonstrated that testosterone treatment results in elevation of oxidative stress levels, particularly lipid peroxidation, and intracellular iron accumulation in granulosa cells. The expression of genes and proteins associated with factors related to ferroptosis, mitochondrial membrane potential and ultrastructure showed that testosterone activated ferroptosis, whereas Fer-1 reversed these alterations. During in-vitro experiments, activation of endoplasmic reticulum stress induced by testosterone treatment was detected in granulosa cells. In granulosa cells, TUDCA, an inhibitor of endoplasmic reticulum stress, significantly mitigated testosterone-induced ferroptosis.

CONCLUSIONS

Ferroptosis plays a part in reproductive injury mediated by hyperandrogens associated with PCOS, and may be regulated by endoplasmic reticulum stress.

Hyperandrogenic environment regulates the function of ovarian granulosa cells by modulating macrophage polarization in PCOS

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder characterized by oligo-anovulation, hyperandrogenism, and polycystic ovaries, with hyperandrogenism being the most prominent feature of PCOS patients. However, whether excessive androgens also exist in the ovarian microenvironment of patients with PCOS, and their modulatory role on ovarian immune homeostasis and ovarian function, is not clear.

METHODS

Follicular fluid samples from patients participating in their first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment were collected. Androgen concentration of follicular fluid was assayed by chemiluminescence, and the macrophage M1:M2 ratio was detected by flow cytometry. In an in vitro model, we examined the regulatory effects of different concentrations of androgen on macrophage differentiation and glucose metabolism levels using qRT-PCR, Simple Western and multi-factor flow cytometry assay. In a co-culture model, we assessed the effect of a hyperandrogenic environment in the presence or absence of macrophages on the function of granulosa cells using qRT-PCR, Simple Western, EdU assay, cell cycle assay, and multi-factor flow cytometry assay.

RESULTS

The results showed that a significantly higher androgen level and M1:M2 ratio in the follicular fluid of PCOS patients with hyperandrogenism. The hyperandrogenic environment promoted the expression of pro-inflammatory and glycolysis-related molecules and inhibited the expression of anti-inflammatory and oxidative phosphorylation-related molecules in macrophages. In the presence of macrophages, a hyperandrogenic environment significantly downregulated the function of granulosa cells.

CONCLUSION

There is a hyperandrogenic microenvironment in the ovary of PCOS patients with hyperandrogenism. Hyperandrogenic microenvironment can promote the activation of ovarian macrophages to M1, which may be associated with the reprogramming of macrophage glucose metabolism. The increased secretion of pro-inflammatory cytokines by macrophages in the hyperandrogenic microenvironment would impair the normal function of granulosa cells and interfere with normal ovarian follicle growth and development.

The Role of Anti-Müllerian Hormone in Ovarian Function

Anti-Müllerian hormone (AMH) is a member of the transforming growth factor β (TGFβ) superfamily, whose actions are restricted to the endocrine-reproductive system. Initially known for its role in male sex differentiation, AMH plays a role in the ovary, acting as a gatekeeper in folliculogenesis by regulating the rate of recruitment and growth of follicles. In the ovary, AMH is predominantly expressed by granulosa cells of preantral and antral follicles (i.e., post primordial follicle recruitment and prior to follicle-stimulating hormone (FSH) selection). AMH signals through a BMP-like signaling pathway in a manner distinct from other TGFβ family members. In this review, the latest insights in AMH processing, signaling, its regulation of spatial and temporal expression pattern, and functioning in folliculogenesis are summarized. In addition, effects of AMH variants on ovarian function are reviewed.

Reproductive Profile of Neuronal Androgen Receptor Knockout Female Mice With a Low Dose of DHT

Hyperandrogenism and polycystic ovarian syndrome result from the imbalance or increase of androgen levels in females. Androgen receptor (AR) mediates the effects of androgens, and this study examines whether neuronal AR plays a role in reproduction under normal and increased androgen conditions in female mice. The neuron-specific AR knockout (KO) mouse (SynARKO) was generated from a female mouse (synapsin promoter driven Cre) and a male mouse (Ar fl/y). Puberty onset and the levels of reproductive hormones such as LH, FSH, testosterone, and estradiol were comparable between the control and the SynARKO mice. There were no differences in cyclicity and fertility between the control and SynARKO mice, with similar impairment in both groups on DHT treatment. Neuronal AR KO, as in this SynARKO mouse model, did not alleviate the infertility associated with DHT treatment. These studies suggest that neuronal AR KO neither altered reproductive function under physiological androgen levels, nor restored fertility under hyperandrogenic conditions.

Induced Pluripotent Stem Cells as a Possible Approach for Exploring the Pathophysiology of Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the most prevalent endocrine condition among women with pleiotropic sequelae possessing reproductive, metabolic, and psychological characteristics. Although the exact origin of PCOS is elusive, it is known to be a complex multigenic disorder with a genetic, epigenetic, and environmental background. However, the pathogenesis of PCOS, and the role of genetic variants in increasing the risk of the condition, are still unknown due to the lack of an appropriate study model. Since the debut of induced pluripotent stem cell (iPSC) technology, the ability of reprogrammed somatic cells to self-renew and their potential for multidirectional differentiation have made them excellent tools to study different disease mechanisms. Recently, researchers have succeeded in establishing human in vitro PCOS disease models utilizing iPSC lines from heterogeneous PCOS patient groups (iPSCPCOS). The current review sets out to summarize, for the first time, our current knowledge of the implications and challenges of iPSC technology in comprehending PCOS pathogenesis and tissue-specific disease mechanisms. Additionally, we suggest that the analysis of polygenic risk prediction based on genome-wide association studies (GWAS) could, theoretically, be utilized when creating iPSC lines as an additional research tool to identify women who are genetically susceptible to PCOS. Taken together, iPSCPCOS may provide a new paradigm for the exploration of PCOS tissue-specific disease mechanisms.

Dysfunction of Human Estrogen Signaling as a Novel Molecular Signature of Polycystic Ovary Syndrome

Estradiol (E2) is a major hormone-controlling folliculogenesis whose dysfunction may participate in polycystic ovary syndrome (PCOS) infertility. To determine whether both the concentration and action of E2 could be impaired in non-hyperandrogenic overweight PCOS women, we isolated granulosa cells (GCs) and follicular fluid (FF) from follicles of women undergoing ovarian stimulation (27 with PCOS, and 54 without PCOS). An analysis of the transcript abundance of 16 genes in GCs showed that androgen and progesterone receptor expressions were significantly increased in GCs of PCOS (by 2.7-fold and 1.5-fold, respectively), while those of the steroidogenic enzymes CYP11A1 and HSD3B2 were down-regulated (by 56% and 38%, respectively). Remarkably, treatment of GC cultures with E2 revealed its ineffectiveness in regulating the expression of several key endocrine genes (e.g., GREB1 or BCL2) in PCOS. Additionally, a comparison of the steroid concentrations (measured by GC/MS) in GCs with those in FF of matched follicles demonstrated that the significant decline in the E2 concentration (by 23%) in PCOS FF was not the result of the E2 biosynthesis reduction. Overall, our study provides novel hallmarks of PCOS by highlighting the ineffective E2 signaling in GCs as well as the dysregulation in the expression of genes involved in follicular growth, which may contribute to aberrant folliculogenesis in non-hyperandrogenic women with PCOS.

Body Fat Distribution and Female Infertility: a Cross-Sectional Analysis Among US Women

At present, the effect of body fat distribution on female reproductive health is still inconclusive. The purpose of our study was to analyze the correlation between female infertility rates and the fat mass portion of the android region to the gynoid region (the A/G ratio) among US women of reproductive age. Female infertility is defined as a failure to get pregnant after 12 months of unprotected sexual activity. A total of 3434 women of reproductive age were included in this study as part of the 2013-2018 National Health and Nutrition Examination Survey (NHANES). The A/G ratio was used to assess the body fat distribution of participants. Based on the comprehensive study design and sample weights, it was determined that the A/G ratio was associated with female infertility primarily through logistic regression analyses. After adjusting for potential confounders, the multivariate regression analysis indicated an increase in the A/G ratio was correlated with an increase in the prevalence of female infertility (OR = 4.374, 95% CI:1.809-10.575). Subgroup analyses showed an increased prevalence of infertility in non-Hispanic Whites (P = 0.012), non-diabetic individuals (P = 0.008), individuals under 35 years old (P = 0.002), and individuals with secondary infertility (P = 0.01). The trend tests and smooth curve fitting illustrate a linear trend between the A/G ratio and female infertility. Future researches are warranted to confirm the causal relationship between body fat distribution and female infertility, which may provide an insight into future prevention and treatment of female infertility.

Polycystic Ovary Syndrome: Pathophysiology and Controversies in Diagnosis

Polycystic ovary syndrome (PCOS) is a complex and heterogeneous disorder that commonly affects women in the reproductive age group. The disorder has features that propose a blend of functional reproductive disorders, such as anovulation and hyperandrogenism, and metabolic disorders, such as hyperglycemia, hypertension, and obesity in women. Until today, the three implemented groups of criteria for the diagnosis of PCOS are from the National Institutes of Health (NIH) in the 1990s, Rotterdam 2003, and the Androgen Excess Polycystic Ovary Syndrome 2009 criteria. Currently, the most widely utilized criteria are the 2003 Rotterdam criteria, which validate the diagnosis of PCOS with the incidence of two out of the three criteria: hyperandrogenism (clinical and/or biochemical), irregular cycles, and polycystic ovary morphology. Currently, the anti-Müllerian hormone in serum is introduced as a substitute for the follicular count and is controversially emerging as an official polycystic ovarian morphology/PCOS marker. In adolescents, the two crucial factors for PCOS diagnosis are hyperandrogenism and irregular cycles. Recently, artificial intelligence, specifically machine learning, is being introduced as a promising diagnostic and predictive tool for PCOS with minimal to zero error that would help in clinical decisions regarding early management and treatment. Throughout this review, we focused on the pathophysiology, clinical features, and diagnostic challenges in females with PCOS.

Androgen increases klotho expression via the androgen receptor-mediated pathway to induce GCs apoptosis

BACKGROUND

Many epidemiological studies have shown that anovulatory polycystic ovary syndrome (PCOS) is accompanied by hyperandrogenism. However, the exact mechanism of hyperandrogen-induced anovulation remains to be elucidated. In this study, we aimed to investigate the potential mechanism of anovulation in PCOS. To investigate the role of klotho as a key factor in the androgen receptor (AR)-mediated development of PCOS, we investigated the effects of testosterone on ovarian klotho expression in vivo and in vitro.

RESULTS

Testosterone propionate (TP)-induced rats showed cycle irregularity, hyperandrogenism, polycystic ovarian changes, dyslipidemia. However, inhibition of AR expression could relieve PCOS traits. We also found that AR and klotho showed relatively high expression in PCOS rat ovarian tissue and in TP-induced granulosa cells (GCs), which was inhibited by the addition of flutamide. TP-induced GCs apoptosis was suppressed by AR antagonist, as well as silencing klotho expression in human GCs. Chromatin immunoprecipitation assay demonstrated that AR indirectly binds to the klotho promoter.

CONCLUSIONS

Our results demonstrated TP mediates the expression of klotho via androgen receptor and klotho alterations could be a reason for ovarian dysfunction in PCOS.

Polycystic ovary syndrome and obesity: a modern paradigm

Polycystic ovary syndrome is a heterogeneous endocrine disease that affects women of childbearing age. The pathogenesis of polycystic ovary syndrome has not been fully studied to date, its paradigm considers the genetic determinism of the manifestation of hormonal and metabolic disorders, which are considered to be criteria for the verification of the disease (hyperandrogenism, oligo/anovulation and/or polycystic ovarian transformation during ultrasound examination (ultrasound). This review discusses the main ways of interaction between hyperandrogenism, insulin resistance and obesity and their role in the pathogenesis of polycystic ovary syndrome, as well as possible methods of treatment for this category of patients. The review analyzes the role of hyperandrogenism and insulin resistance in the implementation of the genetic scenario of polycystic ovary syndrome and finds out the reasons why women with polycystic ovary syndrome often demonstrate the presence of a «metabolic trio» - hyperinsulinemia, insulin resistance and type 2 diabetes mellitus. It is noted that obesity is not included in the criteria for the diagnosis of polycystic ovary syndrome, but epidemiological data confirm the existence of a relationship between these diseases. Obesity, especially visceral, which is often found in women with polycystic ovary syndrome, enhances and worsens metabolic and reproductive outcomes with polycystic ovary syndrome, as well as increases insulin resistance and compensatory hyperinsulinemia, which, in turn, stimulates adipogenesis and suppresses lipolysis. Obesity increases the sensitivity of tech cells to luteinizing hormone stimulation and enhances functional hyperandrogenism of the ovaries, increasing the production of androgens by the ovaries. Excess body weight is associated with a large number of inflammatory adipokines, which, in turn, contribute to the growth of insulin resistance and adipogenesis. Obesity and insulin resistance exacerbate the symptoms of hyperandrogenism, forming a vicious circle that contributes to the development of polycystic ovary syndrome. These data allow us to conclude that bariatric surgery can become an alternative to drugs (metformin, thiazolidinedione analogs of glucagon-like peptide-1), which has shown positive results in the treatment of patients with polycystic ovary syndrome and obesity.

Use of anti-Müllerian hormone for understanding ovulatory dysfunction in polycystic ovarian syndrome

PURPOSE OF REVIEW

The aim of this review is to understand how anti-Müllerian hormone (AMH) contributes to ovulatory dysfunction in polycystic ovarian syndrome (PCOS).

RECENT FINDINGS

In the last few years, new findings have emerged on AMH and its role on the central nervous system causing ovulatory dysfunction.

SUMMARY

Anovulation is a prominent feature of PCOS. Women with anovulatory PCOS have higher AMH levels than in ovulatory PCOS. Higher levels of AMH may contribute to the pathophysiology of PCOS through central and peripheral actions. Once universal standardization is achieved to measure serum AMH, the benefits would be significant in diagnosing women with PCOS.

Age-related changes in Folliculogenesis and potential modifiers to improve fertility outcomes - A narrative review

Reproductive aging is characterized by a decline in oocyte quantity and quality, which is directly associated with a decline in reproductive potential, as well as poorer reproductive success and obstetrical outcomes. As women delay childbearing, understanding the mechanisms of ovarian aging and follicular depletion have become increasingly more relevant. Age-related meiotic errors in oocytes are well established. In addition, it is also important to understand how intraovarian regulators change with aging and how certain treatments can mitigate the impact of aging. Individual studies have demonstrated that reproductive pathways involving antimullerian hormone (AMH), vascular endothelial growth factor (VEGF), neurotropins, insulin-like growth factor 1 (IGF1), and mitochondrial function are pivotal for healthy oocyte and cumulus cell development and are altered with increasing age. We provide a comprehensive review of these individual studies and explain how these factors change in oocytes, cumulus cells, and follicular fluid. We also summarize how modifiers of folliculogenesis, such as vitamin D, coenzyme Q, and dehydroepiandrosterone (DHEA) may be used to potentially overcome age-related changes and enhance fertility outcomes of aged follicles, as evidenced by human and rodent studies.

Key signalling pathways underlying the aetiology of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine condition characterised by a range of reproductive, endocrine, metabolic and psychological abnormalities. Reports estimate that around 10% of women of reproductive age are affected by PCOS, representing a significant prevalence worldwide, which poses a high economic health burden. As the origin of PCOS remains largely unknown, there is neither a cure nor mechanism-based treatments leaving patient management suboptimal and focused solely on symptomatic treatment. However, if the underlying mechanisms underpinning the development of PCOS were uncovered then this would pave the way for the development of new interventions for PCOS. Recently, there have been significant advances in our understanding of the underlying pathways likely involved in PCOS pathogenesis. Key insights include the potential involvement of androgens, insulin, anti-Müllerian hormone and transforming growth factor beta in the development of PCOS. This review will summarise the significant scientific discoveries on these factors that have enhanced our knowledge of the mechanisms involved in the development of PCOS and discuss the impact these insights may have in shaping the future development of effective strategies for women with PCOS.

Association of Insulin Resistance and Elevated Androgen Levels with Polycystic Ovarian Syndrome (PCOS): A Review of Literature

The polycystic ovary syndrome (PCOS) is the disease featured by elevated levels of androgens, ovulatory dysfunction, and morphological abnormalities. At reproductive stage of women, the rate of PCOS occurrence is measured as 6–10% and the prevalence rate may be double. There are different pathophysiological factors involved in PCOS, and they play a major role in various abnormalities in individual patient. It is clear that there is noteworthy elevation of androgen in PCOS, causing substantial misery and infertility problems. The overexposure of androgen is directly linked with insulin resistance and hyperinsulinaemia. It has been reported previously that PCOS is related to cardiac metabolic miseries and potently increases the risk of heart diseases. Endometrial cancer is also a serious concern which is reported with exceedingly high incidence in women with PCOS. However, the overexposure of androgen has direct and specific influence on the development of insulin resistance. Although many factors are involved, resistance to the insulin and enhanced level of androgen are considered the major causes of PCOS. In the present review, we have focused on the pathophysiology and major revolutions of insulin resistance and excessive levels of androgen in females with PCOS.

Estradiol Signaling at the Heart of Folliculogenesis: Its Potential Deregulation in Human Ovarian Pathologies

Estradiol (E2) is a major hormone controlling women fertility, in particular folliculogenesis. This steroid, which is locally produced by granulosa cells (GC) within ovarian follicles, controls the development and selection of dominant preovulatory follicles. E2 effects rely on a complex set of nuclear and extra-nuclear signal transduction pathways principally triggered by its nuclear receptors, ERα and ERβ. These transcription factors are differentially expressed within follicles, with ERβ being the predominant ER in GC. Several ERβ splice isoforms have been identified and display specific structural features, which greatly complicates the nature of ERβ-mediated E2 signaling. This review aims at providing a concise overview of the main actions of E2 during follicular growth, maturation, and selection in human. It also describes the current understanding of the various roles of ERβ splice isoforms, especially their influence on cell fate. We finally discuss how E2 signaling deregulation could participate in two ovarian pathogeneses characterized by either a follicular arrest, as in polycystic ovary syndrome, or an excess of GC survival and proliferation, leading to granulosa cell tumors. This review emphasizes the need for further research to better understand the molecular basis of E2 signaling throughout folliculogenesis and to improve the efficiency of ovarian-related disease therapies.

OUP accepted manuscript

STUDY QUESTION

Do polymorphisms in the anti-Müllerian hormone (AMH) promoter have an effect on AMH levels in patients with polycystic ovary syndrome (PCOS)?

SUMMARY ANSWER

We have identified a novel AMH promoter polymorphism rs10406324 that is associated with lower serum AMH levels and is suggested to play a role in the mechanism of regulation of AMH gene expression in women.

WHAT IS KNOWN ALREADY

Follicle number is positively correlated with serum AMH levels, reflected by elevated AMH levels in women with PCOS. In addition, it is suggested that AMH production per follicle is higher in women with PCOS than in normo-ovulatory women, implying an altered regulation of AMH in PCOS.

STUDY DESIGN, SIZE, DURATION

A discovery cohort of 655 PCOS women of Northern European ancestry and both an internal and external validation PCOS cohort (n = 458 and n = 321, respectively) were included in this study. Summary-level data of an AMH genome-wide association study meta-analysis including 7049 normo-ovulatory women was included as a control cohort. A genetic approach was taken through association analysis and in silico analysis of the associated variants in the AMH promoter. In vitro analysis was performed to investigate the functional mechanisms.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All common two-allelic single-nucleotide polymorphisms (SNPs) in the region Chr19:2 245 353–2 250 827 bp (Build 37) were selected for the analysis. Linear regression analyses were performed to determine the association between SNPs in the AMH promoter region and serum AMH levels. For the in silico analysis, the webtools ‘HaploReg’ v4.1 for ENCODE prediction weight matrices and ‘atSNP’ were used. In vitro analysis was performed using KK1 cells, a mouse granulosa cell line and COV434 cells, a human granulosa tumor cell line. Cells were transfected with the reference or the variant human AMH promoter reporter construct together with several transcription factors (TFs). Dual-Glo^® Luciferase Assay was performed to measure the luciferase activity.

MAIN RESULTS AND THE ROLE OF CHANCE

Polymorphism rs10406324 was significantly associated with serum AMH levels in all three PCOS cohorts. Carriers of the minor allele G had significantly lower log-transformed serum AMH levels compared to non-carriers (P = 8.58 × 10⁻⁸, P = 1.35 × 10⁻³ and P = 1.24 × 10⁻³, respectively). This result was validated in a subsequent meta-analysis (P = 3.24 × 10⁻¹²). Interestingly, rs10406324 was not associated with follicle count, nor with other clinical traits. Also, in normo-ovulatory women, the minor allele of this variant was associated with lower serum AMH levels (P = 1.04 × 10⁻⁵). These findings suggest that polymorphism rs10406324 plays a role in the regulation of AMH expression, irrespective of clinical background. In silico analysis suggested a decreased binding affinity of the TFs steroidogenenic factor 1, estrogen-related receptor alpha and glucocorticoid receptor to the minor allele G variant, however in vitro analysis did not show a difference in promoter activity between the A and G allele.

LIMITATIONS, REASONS FOR CAUTION

Functional analyses were performed in a mouse and a human granulosa cell line using an AMH promoter reporter construct. This may have limited assessment of the impact of the polymorphism on higher order chromatin structures. Human granulosa cells generated from induced pluripotent stem cells, combined with gene editing, may provide a method to elucidate the exact mechanism behind the decrease in serum AMH levels in carriers of the −210 G allele. We acknowledge that the lack of follicle number in the external validation and the control cohort is a limitation of the paper. Although we observed that the association between rs10406324 and AMH levels was independent of follicle number in our discovery and internal validation PCOS cohorts, we cannot fully rule out that the observed effects on serum AMH levels are, in part, caused by differences in follicle number.

WIDER IMPLICATIONS OF THE FINDINGS

These results suggest that variations in serum AMH levels are not only caused by differences in follicle number but also by genetic factors. Therefore, the genetic context should be taken into consideration when assessing serum AMH levels in women. This may have clinical consequences when serum AMH levels are used as a marker for the polycystic ovarian morphology phenotype.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was used. J.S.E.L. has received consultancy fees from the following companies: Ferring, Roche Diagnostics and Ansh Labs and has received travel reimbursement from Ferring. J.A.V. has received royalties from AMH assays, paid to the institute/lab with no personal financial gain. The other authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Metabolic Syndrome and PCOS: Pathogenesis and the Role of Metabolites

Polycystic ovary syndrome (PCOS) is one of the most common endocrine diseases among women of reproductive age and is associated with many metabolic manifestations, such as obesity, insulin resistance (IR) and hyperandrogenism. The underlying pathogenesis of these metabolic symptoms has not yet been fully elucidated. With the application of metabolomics techniques, a variety of metabolite changes have been observed in the serum and follicular fluid (FF) of PCOS patients and animal models. Changes in metabolites result from the daily diet and occur during uncommon physiological routines. However, some of these metabolite changes may provide evidence to explain possible mechanisms and new approaches for prevention and therapy. This article reviews the pathogenesis of PCOS metabolic symptoms and the relationship between metabolites and the pathophysiology of PCOS. Furthermore, the potential clinical application of some specific metabolites will be discussed.

Estradiol promotes cell survival and induces Greb1 expression in granulosa cell tumors of the ovary through an ERα-dependent mechanism

Granulosa cell tumor (GCT) is a form of ovarian tumor characterized by its tendency to recur years after surgical ablation. Little is known on the mechanisms involved in GCT development and progression. GCTs can produce estradiol (E2), but whether this hormone could play a role in this cancer through its nuclear receptors, i.e., ERα and ERβ, remains unknown. Here, we addressed this issue by cell-based and molecular studies on human GCTs and GCT cell lines. Importantly, we observed that E2 significantly increased the growth of GCT cells by promoting cell survival. The use of selective agonists of each type of receptor, together with Esr1 (ERα) or Esr2 (ERβ)-deleted GCT cells revealed that E2 mediated its effects through ERα-dependent genomic mechanisms and ERβ/ERα-dependent extra-nuclear mechanisms. Notably, the expression of Greb1, a prototypical ER target gene, was dose-dependently up-regulated by E2 specifically through ERα in GCT cells. Accordingly, using GCTs from patients, we found that GREB1 mRNA abundance was positively correlated to intra-tumoral E2 concentrations. Tissue microarrays analyses showed that there were various combinations of ER expression in primary and recurrent GCTs, and that ERα expression persisted only in combination with ERβ in ~40% of recurrent tumors. Altogether, this study demonstrates that E2 can promote the progression of GCTs, with a clear dependence on ERα. In addition to demonstrating that GCTs can be classified as a hormone-related cancer, our results also highlight that the nature of ER forms present in recurrent GCTs could underlie the variable efficiency of endocrine therapies. This article is protected by copyright. All rights reserved.

Anti-Müllerian Hormone in Pathogenesis, Diagnostic and Treatment of PCOS

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among reproductive-aged women. It is characterized by chronic anovulation, hyperandrogenism, and the presence of polycystic ovary in ultrasound examination. PCOS is specified by an increased number of follicles at all growing stages, mainly seen in the preantral and small antral follicles and an increased serum level of Anti-Müllerian Hormone (AMH). Because of the strong correlation between circulating AMH levels and antral follicle count on ultrasound, Anti-Müllerian Hormone has been proposed as an alternative marker of ovulatory dysfunction in PCOS. However, the results from the current literature are not homogeneous, and the specific threshold of AMH in PCOS and PCOM is, therefore, very challenging. This review aims to update the current knowledge about AMH, the pathophysiology of AMH in the pathogenesis of PCOS, and the role of Anti-Müllerian Hormone in the treatment of this syndrome.

Anti-Müllerian Hormone in Female Reproduction

Anti-Müllerian hormone (AMH), also called Müllerian inhibiting substance, was shown to be synthesized by the ovary in the 1980s. This article reviews the main findings of the past 20 years on the regulation of the expression of AMH and its specific receptor AMHR2 by granulosa cells, the mechanism of action of AMH, the different roles it plays in the reproductive organs, its clinical utility, and its involvement in the principal pathological conditions affecting women. The findings in respect of regulation tell us that AMH and AMHR2 expression is mainly regulated by bone morphogenetic proteins, gonadotropins, and estrogens. It has now been established that AMH regulates the different steps of folliculogenesis and that it has neuroendocrine effects. On the other hand, the importance of serum AMH as a reliable marker of ovarian reserve and as a useful tool in the prediction of the polycystic ovary syndrome (PCOS) and primary ovarian failure has also been acknowledged. Last but not least, a large body of evidence points to the involvement of AMH in the pathogenesis of PCOS.

Dulaglutide, a long-acting GLP-1 receptor agonist, can improve hyperandrogenemia and ovarian function in DHEA-induced PCOS rats

OBJECTIVE

The purpose of this study was to explore the effect of dulaglutide on DHEA induced PCOS rats and its mechanism, to provide new drugs and research directions for clinical treatment of PCOS.

METHODS

In this study, the PCOS model was established by giving female SD rats subcutaneous injection of DHEA for 21 consecutive days. After modeling, the treatment group was injected subcutaneously with three doses of dulaglutide for 3 weeks. The model group was injected with sterile ultrapure water, and the normal group did not get any intervention. The body weight changes of rats in each group were recorded from the first day when rats received the administration of dulaglutide. Three weeks later, the rats were fasted the night after the last treatment, determined fasting insulin and fasting glucose the next day. After the rats were anesthetized by chloral hydrate, more blood was collected from the heart of the rat. The serum insulin, testosterone and sex hormone binding globulin (SHBG) levels were detected by the enzyme-linked immunoassay method. After removing the adipose tissue, the obtained rat ovary tissue was used for subsequent experimental detection, using HE staining for morphology and follicular development analysis; qRT-PCR for the detection of 3βHSD, CYP17α1, CYP19α1, and StAR gene expression in ovarian tissue; and western blotting analysis of CYP17α1, CYP19α1, StAR protein expression and insulin level to verify whether dulaglutide has a therapeutic effect on PCOS in rats.

RESULTS

After treated with different concentrations of dulaglutide, we found that the body weight of rats in the treatment groups were reduced. Compared with the rats in PCOS group, the serum androgen level of rats in the treatment groups was significantly decreased, and the serum sex hormone binding protein content was significantly increased, and there was statistically significant difference between these groups and PCOS group. In terms of protein expression and gene regulation, the expression of 3βHSD, CYP19α1 and StAR in the ovarian tissue of rats in treatment groups were decreased significantly after received the treatment of dulaglutide, and there was statistically significant difference between these groups and PCOS group. In addition, dulaglutide reduced the insulin content in the ovarian tissue of PCOS rats.

CONCLUSION

Dulaglutide may reduce the hyperandrogenemia of PCOS rats by regulating the content of serum SHBG and the expression of 3βHSD, CYP19α1, and StAR related genes and proteins, thereby inhibiting the excessive development of small follicles and the formation of cystic follicles in the ovaries of PCOS rats, thereby improving polycystic ovary in PCOS rats. In addition, dulaglutide may reduce the weight of PCOS rats, further reducing the level of high androgen in PCOS rats, and improving the morphology of their polycystic ovaries.

Estradiol Regulates mRNA Levels of Estrogen Receptor Beta 4 and Beta 5 Isoforms and Modulates Human Granulosa Cell Apoptosis

Estrogen receptor beta (ERβ) plays a critical role in granulosa cell (GC) functions. The existence of four human ERβ splice isoforms in the ovary suggests their differential implication in 17β-estradiol (E2) actions on GC apoptosis causing follicular atresia. In this study, we investigated whether E2 can regulate ERβ isoforms expression to fine tune its apoptotic activities in human GC. For this purpose, we measured by RT-qPCR the expression of ERβ isoforms in primary culture of human granulosa cells (hGCs) collected from patients undergoing in vitro fertilization, before and after E2 exposure. Besides, we assessed the potential role of ERβ isoforms on cell growth and apoptosis after their overexpression in a human GC line (HGrC1 cells). We confirmed that ERβ1, ERβ2, ERβ4, and ERβ5 isoform mRNAs were predominant over that of ERα in hGCs, and found that E2 selectively regulates mRNA levels of ERβ4 and ERβ5 isoforms in these cells. In addition, we demonstrated that overexpression of ERβ1 and ERβ4 in HGrC1 cells increased cell apoptosis by 225% while ERβ5 or ERβ2 had no effect. Altogether, our study revealed that E2 may influence GC fate by specifically regulating the relative abundance of ERβ isoforms mRNA to modulate the balance between pro-apoptotic and non-apoptotic ERβ isoforms.

Obesity and the Risk of Infertility, Gestational Diabetes, and Type 2 Diabetes in Polycystic Ovary Syndrome

This review describes the relationship between obesity and the most common reproductive (infertility) and metabolic (gestational diabetes mellitus [GDM] and type 2 diabetes mellitus [T2DM]) consequences in polycystic ovary syndrome (PCOS). It also describes the vital role of lifestyle management for PCOS. PCOS is a heterogeneous endocrine disorder common in reproductive-age women. Consensus on the exact etiological mechanisms of PCOS is unreached. Overweight or obesity is present in at least 60% of the PCOS population, but the condition occurs irrespective of BMI, with excess BMI increasing both the prevalence and severity of clinical features. Use of lifestyle therapies (nutrition, physical activity, and/or behavioral) for the prevention and management of excess weight gain, infertility, GDM, and T2DM is a vital component of best-practice PCOS care. Lifestyle management is recommended for all women with PCOS as the first-line treatment with or without medications. Due to a lack of high-quality trials demonstrating the efficacy of specific lifestyle approaches, PCOS lifestyle recommendations are as those for the general population. This review summarizes current knowledge relating to obesity and its impact on fertility, GDM, and T2DM. It also summarizes the lifestyle recommendations to best manage these conditions in women with PCOS and obesity.

The Goto-Kakizaki rat is a spontaneous prototypical rodent model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is characterized by an oligo-anovulation, hyperandrogenism and polycystic ovarian morphology combined with major metabolic disturbances. However, despite the high prevalence and the human and economic consequences of this syndrome, its etiology remains unknown. In this study, we show that female Goto-Kakizaki (GK) rats, a type 2 diabetes mellitus model, encapsulate naturally all the reproductive and metabolic hallmarks of lean women with PCOS at puberty and in adulthood. The analysis of their gestation and of their fetuses demonstrates that this PCOS-like phenotype is developmentally programmed. GK rats also develop features of ovarian hyperstimulation syndrome. Lastly, a comparison between GK rats and a cohort of women with PCOS reveals a similar reproductive signature. Thus, this spontaneous rodent model of PCOS represents an original tool for the identification of the mechanisms involved in its pathogenesis and for the development of novel strategies for its treatment.

The Relationship of Anti-Mullerian Hormone in Polycystic Ovary Syndrome Patients with Different Subgroups

PURPOSE

To explore the value of anti-Mullerian hormone (AMH) in patients with polycystic ovary syndrome (PCOS) with different phenotypes and ages, and to identify the relationship between hyperandrogenism (HA) and polycystic ovary morphology (PCOM), in a Chinese cohort.

METHODS

A total of 2262 women (1631 with PCOS and 631 controls) were enrolled. The serum AMH and total testosterone (TT) were analyzed, the AMH levels of each subgroup were compared, and the value of each phenotype and age group of patients with PCOS was evaluated.

RESULTS

The level of AMH in women with PCOS (mean±SD, 8.63±4.73 ng/mL) was higher than that in controls (5.57±3.31 ng/mL) (P<0.01). The level of AMH in the PCOM subgroup (11.19±6.4 ng/mL) was significantly higher than that in the HA subgroup (8.58±4.74 ng/mL) (P<0.01), and both were higher than that in controls (P<0.01). AMH was higher in PCOS patients than in controls, but the same values were found in subgroups of PCOS patients under 30 years old.

CONCLUSION

AMH changed in different subgroups of PCOS, which was the possible reason why AMH was not a diagnostic indicator. However, AMH could help to differentiate between clinical subgroups, as it was strongly related with PCOM but not with HA. AMH changed substantially with age, but was stable in PCOS patients under 30 years old.

The regulation and signalling of anti-Müllerian hormone in human granulosa cells: relevance to polycystic ovary syndrome

STUDY QUESTION

What prevents the fall in anti-Müllerian hormone (AMH) levels in polycystic ovary syndrome (PCOS) and what are the consequences of this for follicle progression in these ovaries?

SUMMARY ANSWER

Exposure of granulosa cells (GCs) to high levels of androgens, equivalent to that found in PCOS, prevented the fall in AMH and was associated with dysregulated AMH-SMAD signalling leading to stalled follicle progression in PCOS.

WHAT IS KNOWN ALREADY

In normal ovaries, AMH exerts an inhibitory role on antral follicle development and a fall in AMH levels is a prerequisite for ovulation. Levels of AMH are high in PCOS, contributing to the dysregulated follicle growth that is a common cause of anovulatory infertility in these women.

STUDY DESIGN, SIZE, DURATION

Human KGN-GC (the cell line that corresponds to immature GC from smaller antral follicles (AF)) were cultured with a range of doses of various androgens to determine the effects on AMH production. KGN-GC were also treated with PHTPP (an oestrogen receptor β (ERβ) antagonist) to examine the relationship between AMH expression and the ratio of ERα:ERβ. The differential dose-related effect of AMH on gene expression and SMAD signalling was investigated in human granulosa-luteal cells (hGLC) from women with normal ovaries, with polycystic ovarian morphology (PCOM) and with PCOS. KGN-GC were also cultured for a prolonged period with AMH at different doses to assess the effect on cell proliferation and viability.

PARTICIPANTS/MATERIALS, SETTING, METHODS

AMH protein production by cells exposed to androgens was measured by ELISA. The effect of PHTPP on the mRNA expression levels of AMH, ERα and ERβ was assessed by real-time quantitative PCR (qPCR). The influence of AMH on the relative mRNA expression levels of aromatase, AMH and its receptor AMHRII, and the FSH and LH receptor (FSHR and LHR) in control, PCOM and PCOS hGLCs was quantified by qPCR. Western blotting was used to assess changes in levels of SMAD proteins (pSMAD-1/5/8; SMAD-4; SMAD-6 and SMAD-7) after exposure of hGLCs from healthy women and women with PCOS to AMH. The ApoTox-Glo Triplex assay was used to evaluate the effect of AMH on cell viability, cytotoxicity and apoptosis.

MAIN RESULTS AND THE ROLE OF CHANCE

Testosterone reduced AMH protein secreted from KGN-GC at 10-9-10-7 M (P < 0.05; P < 0.005, multiple uncorrected comparisons Fishers least squares difference), but at equivalent hyperandrogenemic levels no change was seen in AMH levels. 5α-DHT produced a significant dose-related increase in AMH protein secreted into the media (P = 0.022, ANOVA). Increasing the mRNA ratio of ERα:ERβ produced a corresponding increase in AMH mRNA expression (P = 0.015, two-way ANOVA). AMH increased mRNA levels of aromatase (P < 0.05, one-way ANOVA) and FSHR (P < 0.0001, one-way ANOVA) in hGLCs from women with PCOM, but not from normal cells or PCOS (normal n = 7, PCOM n = 5, PCOS n = 4). In contrast to hGLCs from ovulatory ovaries, in PCOS AMH reduced protein levels (cell content) of stimulatory pSMAD-1/5/8 and SMAD-4 but increased inhibitory SMAD-6 and -7 (P < 0.05, normal n = 6, PCOS n = 3). AMH at 20 and 50 ng/ml decreased KGN-GC cell proliferation but not viability after 8 days of treatment (P < 0.005, two-way ANOVA).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Luteinised GC from women undergoing IVF have a relatively low expression of AMH/AMHRII but advantageously continue to display responses inherent to the ovarian morphology from which they are collected. To compensate, we also utilised the KGN cell line which has been characterised to be at a developmental stage close to that of immature GC. The lack of flutamide influence on testosterone effects is not in itself sufficient evidence to conclude that the effect on AMH is mediated via conversion to oestrogen, and the effect of aromatase inhibitors or oestrogen-specific inhibitors should be tested. The effect of flutamide was tested on testosterone but not DHT.

WIDER IMPLICATIONS OF THE FINDINGS

Normal folliculogenesis and ovulation are dependent on the timely reduction in AMH production from GC at the time of follicle selection. Our findings reveal for the first time that theca-derived androgens may play a role in this model but that this inhibitory action is lost at levels of androgens equivalent to those seen in PCOS. The AMH decline may either be a direct effect of androgens or an indirect one via conversion to oestradiol and acting through the upregulation of ERα, which is known to stimulate the AMH promoter. Interestingly, the ability of GCs to respond to this continually elevated AMH level appears to be reduced in cells from women with PCOS due to an adaptive alteration in the SMAD signalling pathway and lower expression of AMHRII, indicating a form of 'AMH resistance'.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Thomas Addison Scholarship, St Georges Hospital Trust. The authors report no conflict of interest in this work and have nothing to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Anti-Müllerian hormone production in the ovary: a comparative study in bovine and porcine granulosa cells†

In this study, we aimed to determine the origin of the difference, in terms of anti-Müllerian hormone production, existing between the bovine and porcine ovaries. We first confirmed by quantitative real-time-Polymerase-Chain Reaction, ELISA assay and immunohistochemistry that anti-Müllerian hormone mRNA and protein production are very low in porcine ovarian growing follicles compared to bovine ones. We then have transfected porcine and bovine granulosa cells with vectors containing the luciferase gene driven by the porcine or the bovine anti-Müllerian hormone promoter. These transfection experiments showed that the porcine anti-Müllerian hormone promoter is less active and less responsive to bone morphogenetic protein stimulations than the bovine promoter in both porcine and bovine cells. Moreover, bovine but not porcine granulosa cells were responsive to bone morphogenetic protein stimulation after transfection of a plasmidic construction including a strong response element to the bone morphogenetic proteins (12 repetitions of the GCCG sequence) upstream of the luciferase reporter gene. We also showed that SMAD6, an inhibitor of the SMAD1-5-8 pathway, is strongly expressed in porcine compared to the bovine granulosa cells. Overall, these results suggest that the low expression of anti-Müllerian hormone in porcine growing follicles is due to both a lack of activity/sensitivity of the porcine anti-Müllerian hormone promoter, and to the lack of responsiveness of porcine granulosa cells to bone morphogenetic protein signaling, potentially due to an overexpression of SMAD6 compared to bovine granulosa cells. We propose that the low levels of anti-Müllerian hormone in the pig would explain the poly-ovulatory phenotype in this species.

Diagnosis and Management of Polycystic Ovary Syndrome in Adolescents

Polycystic ovary syndrome (PCOS) is a common female reproductive disorder that often manifests during adolescence and is associated with disruptions in health-related quality of life. Prompt evaluation and clinical support after diagnosis may prevent associated complications and optimize overall health management. This article incorporates the most recent evidence and consensus guidelines to provide an updated review of the pathogenesis, clinical presentation, diagnostic evaluation, and management strategies for adolescents with this complex condition. We will review the recent international guidelines on PCOS; because the diagnosis of PCOS remains controversial, management of this condition is inconsistent. In 2019, PCOS remains a common, yet neglected, condition, in part, because of the lack of agreement around both diagnosis and management.

Role of Anti-Müllerian Hormone in the Pathogenesis of Polycystic Ovary Syndrome

Besides its interest for diagnosis, the finding of an elevated serum AMH level in PCOS has open major pathophysiological issues. This review addresses the three most important issues: 1- the role of AMH in the disturbed folliculogenesis of PCOS; 2- the role of AMH in the gonadotropin dysregulation of PCOS and 3- the role of AMH in the trans-generational transmission of PCOS. For each of those issues, the clinical and experimental evidences currently available are discussed and pathophysiological hypothesis are proposed.

Investigation of soluble anti-Müllerian hormone receptor type 2 as a biomarker for diagnosis of female fertility disorders

RESEARCH QUESTION

The ectodomain of the anti-Müllerian hormone (AMH) type 2 receptor is shed by proteases under certain conditions, which makes it measurable in the blood. The aim of this study was to identify correlations of soluble anti-Müllerian hormone receptor type 2 (sAMHR2) with other sex hormone concentrations and to assess whether sAMHR2 may serve as a new biomarker in fertility disorders.

DESIGN

In a retrospective cross-sectional study of women (n = 186) with different gynaecological-endocrinological disorders, mixed-effect models were used to analyse the correlation with established diagnostic hormone tests. Receiver operating characteristic curve analysis was performed to assess the diagnostic performance.

RESULTS

There was a strong correlation of sAMHR2 with LH (r = 0.898) and FSH (r = 0.846) and a moderate correlation of AMH with testosterone (r = 0.666) and androstenedione (r = 0.696) (all P < 0.001). In diagnoses of polycystic ovary syndrome (PCOS), AMH showed the best performance (area under the curve [AUC] 0.981, cut-off 4 ng/ml) with 96% sensitivity and 94% specificity. sAMHR2 concentrations and sAMHR2/AMH ratios were elevated in women with ovarian insufficiency, compared with all other study groups, including post-menopausal women on hormone replacement therapy. Highest sensitivity and specificity (100% and 98.2%, respectively) were achieved with sAMHR2/AMH ratio for the diagnosis of post-menopausal status (cut-off 68.85). The sAMHR2/AMH ratio (AUC 0.997) had a better performance than sAMHR2 (AUC 0.947), FSH (AUC 0.989) and LH (AUC 0.967).

CONCLUSIONS

The sAMHR2/AMH ratio may serve as a useful biomarker for infertility diagnostics to identify post-menopausal women.

Polycystic ovarian syndrome: Correlation between hyperandrogenism, insulin resistance and obesity

Polycystic ovary syndrome (PCOS) is a complex and heterogeneous endocrine disease characterized by clinical or laboratorial hyperandrogenism, oligo-anovulation and metabolic abnormalities, including insulin resistance, excessive weight or obesity, type II diabetes, dyslipidemia and an increased risk of cardiovascular disease. The most significant clinical manifestation of PCOS is hyperandrogenism. Excess androgen profoundly affects granulosa cell function and follicular development via complex mechanisms that lead to obesity and insulin resistance. Most PCOS patients with hyperandrogenism have steroid secretion defects that result in abnormal folliculogenesis and failed dominant follicle selection. Hyperandrogenism induces obesity, hairy, acne, and androgenetic alopecia. These symptoms can bring great psychological stress to women. Drugs such as combined oral contraceptive pills, metformin, pioglitazone and low-dose spironolactone help improve pregnancy rates by decreasing androgen levels in vivo. Notably, PCOS is heterogeneous, and hyperandrogenism is not the only pathogenic factor. Obesity and insulin resistance aggravate the symptoms of hyperandrogenism, forming a vicious cycle that promotes PCOS development. Although numerous studies have been conducted, the definitive pathogenic mechanisms of PCOS remain uncertain. This review summarizes and discusses previous and recent findings regarding the relationship between hyperandrogenism, insulin resistance, obesity and PCOS.

Anti-Müllerian hormone inhibits luteinizing hormone-induced androstenedione synthesis in porcine theca cells

AMH (Anti-Müllerian Hormone) is involved in the regulation of follicle growth initiation and inhibits FSH-induced aromatase expression and estrogen production in granulosa cells. However, the function of AMH in steroidogenesis by theca cells remains unclear. The aim of this study is to investigate the role of AMH as a regulator of the basal and stimulated steroid production by pig granulosa cells (pGCs) and theca cells (pTCs). PGCs and pTCs were incubated with hormones AMH, LH (luteinizing hormone), FSH (follicle stimulating hormone), individually or in combination. The expression of CYP19A1, HSD3B1, CYP11A1, LHCGR, and CYP17A1 mRNA were evaluated by quantitative reverse transcriptase PCR. In pGCs, 10 ng/mL AMH significantly decreased the FSH-stimulated effect on FSHR and CYP19A1 expression and estradiol production. In pTCs, LH treatment significantly increased the expression of HSD3B1, CYP11A1, LHCGR, and androstenedione or progesterone production (P < 0.05). Additionally, 10 ng/mL AMH also significantly decreased the LH-stimulated effects on the expression of HSD3B1, CYP11A1, CYP17A1, LHCGR and androstenedione production. Transfection with siAMHR2-I abolished the suppressive effects of AMH on LH-induced HSD3B1 expression and androstenedione production. Taken together, these results demonstrate that AMH is involved in FSH induced estradiol production in pGCs and LH induced androstenedione production in pTCs by regulating the steroidogenesis pathway.

Hyperactive CREB signaling pathway involved in the pathogenesis of polycystic ovarian syndrome revealed by patient-specific induced pluripotent stem cell modeling

OBJECTIVE

To study whether and how the pathogenesis of polycystic ovarian syndrome (PCOS) is related to epigenetic aberrations.

DESIGN

A case-control experimental study.

SETTING

Tertiary university hospital.

PATIENT(S)

Eighteen patients with PCOS and ten non-PCOS control subjects.

INTERVENTIONS(S)

Patient-specific induced pluripotent stem cells (iPSCs) were obtained from skin fibroblasts through the application of nonviral episomal reprogramming and were differentiated into ovarian granulosa cells (GCs) with the use of a cocktail of growth factors. Primary ovarian GCs were collected during transvaginal oocyte retrieval surgery.

MAIN OUTCOME MEASURE(S)

Characterization and functional validation of iPSC-derived GCs were conducted. Whole-genomic DNA methylation profiles in women with and without PCOS in both iPSC-derived GCs and primary adult GCs were analyzed with the use of the Illumina 850K MethylationEPIC Beadchip.

RESULT(S)

The iPSC-derived GCs successfully expressed GC-associated genes and aromatase activity after differentiation. Whole-genomic DNA methylation analysis of the iPSC-derived GCs and adult GCs both revealed a hyperactive CREB signaling pathway in the PCOS group compared with the control group. The expression of CREB-binding protein (CBP) mRNA was significantly higher in the iPSC-derived GCs in the PCOS group, and the expression of CBP protein was also significantly higher in the primary GCs from women with PCOS.

CONCLUSION(S)

The combination of DNA methylomic analysis in primary adult GCs and iPSC-derived GCs showed that a preserved persistent hyperactivation of the CREB signaling pathway might be involved in the pathogenesis of PCOS. These results could have implications on the early developmental origin, inheritance nature, and environmental interaction effects of this disease.

Multi-system reproductive metabolic disorder: significance for the pathogenesis and therapy of polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome (PCOS), a multisystem disease, is a major reason for female infertility around the world. It is no longer considered simply as a disease of ovary. Now researchers growing awareness of the multisystem features of this disease. PCOS has a higher relationship with metabolic disturbance and hypothalamic-pituitary-ovarian axis (HPOA) function disorders. This syndrome results in hyperandrogenemia (HA), hyperinsulinemia/insulin resistance (IR), increased estrone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) ratio imbalance, infertility, cardiovascular diseases, endometrial dysfunction, obesity, and including a litany of other health issues. Furthermore, PCOS has been garnered in recent times. Interventions like metformin, orlistat, hormonal contraceptives, GLP1 agonists, and VitD have been applied to ameliorate or reverse the pathological characterization of PCOS. Moreover, drug-combined therapy of PCOS is superior to single drug administration. This review will focus on the recent progress in pathogenesis and therapy of PCOS.

Anti-Müllerian Hormone in Girls with Premature Adrenarche: The Impact of Polycystic Ovary Syndrome History in their Mothers

OBJECTIVES

To assess whether the serum levels of anti-Müllerian hormone (AMH) are increased in girls with premature adrenarche because they are at a higher risk of developing polycystic ovary syndrome (PCOS) later in life.

STUDY DESIGN

We measured serum levels of AMH, dehydroepiandrosterone sulfate (DHEAS), testosterone, sex hormone binding globulin, androstenedione, and 17-hyroxyprogesterone in 89 girls with premature adrenarche aged 6.98 ± 1.60 years, and in 55 prepubertal normal girls aged 6.78 ± 1.60 years.

RESULTS

AMH was significantly higher in girls with premature adrenarche (2.95 ± 1.20 ng/mL) compared with normal prepubertal girls (2.00 ± 0.95 ng/mL; P < .001), whereas their body mass index SD score was similar (P > .05). DHEAS, testosterone, and androstenedione were increased in premature adrenarche, whereas sex hormone binding globulin was decreased in girls with premature adrenarche. Among the 89 girls with premature adrenarche, 33 were daughters of mothers with a positive history of PCOS, whereas the mothers of the remaining 56 girls with premature adrenarche had a negative history of PCOS. The girls with a mother with a positive history of PCOS had significantly higher AMH serum levels compared with girls with a mother with a negative history of PCOS (3.37 ± 1.72  ng/mL vs 2.70 ± 1.25 ng/mL; P < .05) with no differences in testosterone, DHEAS, androstenedione, and sex hormone binding globulin. The serum concentration of AMH was only positively related to androstenedione (r = 0.538; P < .0001).

CONCLUSIONS

Girls with premature adrenarche, especially those from mothers with a history of PCOS, could have a higher risk of developing PCOS later in life because they have increased serum AMH.

Circulating antimüllerian hormone and steroid hormone levels remain high in pregnant women with polycystic ovary syndrome at term

OBJECTIVE

To investigate plasma antimüllerian hormone (AMH) concentration and its relation to steroid hormone levels in pregnant women with polycystic ovary syndrome (PCOS) and controls at term.

DESIGN

Case-control study.

SETTING

University-affiliated hospital.

PATIENT(S)

A total of 74 pregnant women at term: 25 women with PCOS (aged 31.6 ± 3.9 years [mean ± standard deviation], body mass index 24.0 ± 3.9 kg/m2, mean gestational length 279 ± 9 days) and 49 controls (aged 31.7 ± 3.3 years, body mass index 24.0 ± 3.3 kg/m2, mean gestational length 281 ± 9 days).

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Plasma AMH and steroid hormone levels.

RESULT(S)

Antimüllerian hormone, T, and androstenedione levels were higher in women with PCOS at term compared with controls, whereas estrogen and P levels were similar. The differences were pronounced in women carrying a female fetus. Testosterone and AMH levels correlated positively in both groups, but E₂ levels only in women with PCOS.

CONCLUSION(S)

Pregnant women with PCOS present with elevated AMH and androgen levels even at term, suggesting a hormonal imbalance during PCOS pregnancy. Differences were detected especially in pregnancies with a female fetus, raising the question of whether female pregnancies are more susceptible to AMH and steroid hormone actions.

Anti-müllerian hormone in the pathophysiology and diagnosis of polycystic ovarian syndrome

PURPOSE OF REVIEW

Polycystic ovarian syndrome (PCOS) is the most common cause of chronic anovulation and hyperandrogenism in young women and represents a true public health concern and an economic burden.

RECENT FINDINGS

The pathophysiology of PCOS is still not fully understood, but progresses have been made and the relationships between anti mullerian hormone (AMH), follicle stimulating hormone, luteinizing hormone, E2 and androgens have been explored. The follicle excess plays a central role in the syndrome and AMH is definitively a major component of this phenomena.

SUMMARY

The aim of this chapter is to present the recent work studying the role of AMH in the pathophysiology of PCOS and to discuss the improvement that serum AMH assay brings in the diagnosis of PCOS.

GnRH Transactivates Human AMH Receptor Gene via Egr1 and FOXO1 in Gonadotrope Cells

BACKGROUND/OBJECTIVES

Anti-Müllerian hormone (AMH) signaling is critical for sexual differentiation and gonadal function. AMH receptor type 2 (AMHR2) is expressed in extragonadal sites such as brain, and pituitary and emerging evidence indicates that AMH biological action is much broader than initially thought. We recently reported that AMH signaling enhances follicle-stimulating hormone synthesis in pituitary gonadotrope cells. However, mechanisms regulating AMHR2 expression in these extragonadal sites remain to be explored.

METHOD/RESULTS

Here, we demonstrated in perifused murine LβT2 gonadotrope cells that Amhr2 expression is differentially regulated by GnRH pulse frequency with an induction under high GnRH pulsatility. Furthermore, we showed that GnRH transactivates the human AMHR2 promoter in LβT2 cells. Successive deletions of the promoter revealed the importance of a short proximal region (-53/-37 bp) containing an Egr1 binding site. Using site-directed mutagenesis of Egr1 motif and siRNA mediated-knockdown of Egr1, we demonstrated that Egr1 mediates basal and GnRH-dependent activity of the promoter, identifying Egr1 as a new transcription factor controlling hAMHR2 expression. We also showed that SF1 and β-catenin are required for basal promoter activity and demonstrated that both factors contribute to the GnRH stimulatory effect, independently of their respective binding sites. Furthermore, using a constitutively active mutant of FOXO1, we identified FOXO1 as a negative regulator of basal and GnRH-dependent AMHR2 expression in gonadotrope cells.

CONCLUSIONS

This study identifies GnRH as a regulator of human AMHR2 expression, further highlighting the importance of AMH signaling in the regulation of gonadotrope function.

A Hyperandrogenic Mouse Model to Study Polycystic Ovary Syndrome

Hyperandrogenemia plays a critical role in reproductive and metabolic function in females and is the hallmark of polycystic ovary syndrome. Developing a lean PCOS-like mouse model that mimics women with PCOS is clinically meaningful. In this protocol, we describe such a model. By inserting a 4 mm length of DHT (dihydrotestosterone) crystal powder pellet (total length of pellet is 8 mm), and replacing it monthly, we are able to produce a PCOS-like mouse model with serum DHT levels 2 fold higher than mice not implanted with DHT (no-DHT). We observed reproductive and metabolic dysfunction without changing body weight and body composition. While exhibiting a high degree of infertility, a small subset of these PCOS-like female mice can get pregnant and their offspring show delayed puberty and increased testosterone as adults. This PCOS-like lean mouse model is a useful tool to study the pathophysiology of PCOS and the offspring from these PCOS-like dams.