Novel role for anti-Müllerian hormone in the regulation of GnRH neuron excitability and hormone secretion

Anti-Müllerian Hormone: A Molecular Key to Unlocking Polycystic Ovary Syndrome?

Anti-Müllerian hormone (AMH) is an important component within androgen receptor (AR)-regulated pathways governing the hyperandrogenic origin of polycystic ovary syndrome (PCOS). In women with PCOS, granulosa cell AMH overexpression in developing ovarian follicles contributes to elevated circulating AMH levels beginning at birth and continuing in adolescent daughters of PCOS women. A 6 to 7% incidence among PCOS women of gene variants coding for AMH or its receptor, AMHR2, suggests genetic contributions to AMH-related pathogenesis. Discrete gestational AMH administration to pregnant mice induces hypergonadotropic hyperandrogenic, PCOS-like female offspring with high circulating AMH levels that persist over three generations, suggesting epigenetic contributions to PCOS through developmental programming. Moreover, adult-onset, selective hyperactivation of hypothalamic neurons expressing gonadotropin-releasing hormone (GnRH) induces hypergonadotropic hyperandrogenism and PCOS-like traits in female mice. Both gestational and adult AMH inductions of PCOS-like traits are prevented by GnRH antagonist coadministration, implicating luteinizing hormone-dependent ovarian theca cell testosterone (T) action, mediated through the AR in AMH-induced pathogenesis. Interestingly, gestational or peripubertal exogenous T or dihydrotestosterone induction of PCOS-like traits in female mice, rats, sheep, and monkeys fails to elicit ovarian AMH hypersecretion; thus, AMH excess per se may lead to a distinct pathogenic contribution to hyperandrogenic PCOS origins.

Investigating GABA Neuron-Specific Androgen Receptor Knockout in two Hyperandrogenic Models of PCOS

Androgen excess is a hallmark feature of polycystic ovary syndrome (PCOS), the most common form of anovulatory infertility. Clinical and preclinical evidence links developmental or chronic exposure to hyperandrogenism with programming and evoking the reproductive and metabolic traits of PCOS. While critical androgen targets remain to be determined, central GABAergic neurons are postulated to be involved. Here, we tested the hypothesis that androgen signaling in GABAergic neurons is critical in PCOS pathogenesis in 2 well-characterized hyperandrogenic mouse models of PCOS. Using cre-lox transgenics, GABA-specific androgen receptor knockout (GABARKO) mice were generated and exposed to either acute prenatal androgen excess (PNA) or chronic peripubertal androgen excess (PPA). Females were phenotyped for reproductive and metabolic features associated with each model and brains of PNA mice were assessed for elevated GABAergic input to gonadotropin-releasing hormone (GnRH) neurons. Reproductive and metabolic dysfunction induced by PPA, including acyclicity, absence of corpora lutea, obesity, adipocyte hypertrophy, and impaired glucose homeostasis, was not different between GABARKO and wild-type (WT) mice. In PNA mice, acyclicity remained in GABARKO mice while ovarian morphology and luteinizing hormone secretion was not significantly impacted by PNA or genotype. However, PNA predictably increased the density of putative GABAergic synapses to GnRH neurons in adult WT mice, and this PNA-induced plasticity was absent in GABARKO mice. Together, these findings suggest that while direct androgen signaling in GABA neurons is largely not required for the development of PCOS-like traits in androgenized models of PCOS, developmental programming of GnRH neuron innervation is dependent upon androgen signaling in GABA neurons.

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.

Utility of Serum Anti-Müllerian Hormone Measurement as Part of Polycystic Ovary Syndrome Diagnosis

The 2023 international evidence-based guideline update for the assessment and management of polycystic ovary syndrome (PCOS) recommends using the Rotterdam criteria for the diagnosis of PCOS. The updated guideline has evidence-based recommendation for the diagnosis, and it now also includes serum anti-Müllerian hormone (AMH) measurement as an alternative tool for gynecological ultrasound to diagnose polycystic ovary morphology (PCOM). The aim of this new recommendation was to facilitate PCOS diagnostic workup in primary care and other disciplines, as currently most diagnosing is done in gynecology and infertility clinics. Here, we review factors affecting AMH levels as well as the utility of AMH in PCOS diagnosis. We identified relevant studies that report different cut-offs for AMH to diagnose PCOM as part of PCOS diagnosis. There are, however, some limitations when using AMH that should be acknowledged. These include physiological aspects like age, ethnicity, and obesity and iatrogenic causes like hormonal medication and ovarian surgery. Also reference ranges are different depending on AMH assay used. As a summary, we conclude that AMH is a usable tool in PCOM diagnostics, but it does not have a single cut-off. Therefore, further studies are needed to establish age and assay-based reference ranges.

Polycystic ovary syndrome (PCOS): progress towards a better understanding and treatment of the syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of reproductive age. It has a strong hereditary component estimated at 60 to 70% in daughters. It has been suggested that environmental factors during the fetal period may be involved in the development of the syndrome in adulthood. However, the underlying mechanisms of its transmission remain unknown, thus limiting the development of effective therapeutic strategies.This article highlights how an altered fetal environment (prenatal exposure to high levels of anti-Müllerian hormone) can contribute to the onset of PCOS in adulthood and lead to the transgenerational transmission of neuroendocrine and metabolic traits through alterations in the DNA methylation process.The originality of the translational findings summarized here involves the identification of potential biomarkers for early diagnosis of the syndrome, in addition to the validation of a promising therapeutic avenue in a preclinical model of PCOS, which can improve the management of patients suffering from the syndrome.

Role of Anti-Müllerian Hormone in the Central Regulation of Fertility

In recent years, the expanding roles of anti-Müllerian hormone (AMH) in various aspects of reproductive health have attracted significant attention. Initially recognized for its classical role in male sexual differentiation, AMH is produced postnatally by the Sertoli cells in the male testes and by the granulosa cells in the female ovaries. Traditionally, it was believed to primarily influence gonadal development and function. However, research over the last decade has unveiled novel actions of AMH beyond the gonads, specifically all along the hypothalamic-pituitary-gonadal axis. This review will focus on the emerging roles of AMH within the hypothalamus and discusses its potential implications in reproductive physiology. Additionally, recent preclinical and clinical studies have suggested that elevated levels of AMH may disrupt the hypothalamic network regulating reproduction, which could contribute to the central pathophysiology of polycystic ovary syndrome. These findings underscore the intricate interplay between AMH and the neuroendocrine system, offering new avenues for understanding the mechanisms underlying fertility and reproductive disorders.

Mechanism of elevated LH/FSH ratio in lean PCOS revisited: a path analysis

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting 5-20% of reproductive-age women. However, the treatment of PCOS is mainly based on symptoms and not on its pathophysiology. Neuroendocrine disturbance, as shown by an elevated LH/FSH ratio in PCOS patients, was thought to be the central mechanism of the syndrome, especially in lean PCOS. LH and FSH secretion are influenced by GnRH pulsatility of GnRH neurons in the hypothalamus. Kisspeptin is the main regulator of GnRH secretion, whereas neurokinin B (NKB) and dynorphin regulate kisspeptin secretion in KNDy neurons. This study aims to deepen the understanding of the neuroendocrine disorder in lean PCOS patients and its potential pathophysiology-based therapy. A cross-sectional study was performed at Dr. Cipto Mangunkusumo Kencana Hospital and the IMERI UI HRIFP cluster with 110 lean PCOS patients as subjects. LH, FSH, LH/FSH ratio, kisspeptin, NKB, dynorphin, leptin, adiponectin, AMH, fasting blood glucose, fasting insulin, HOMA-IR, testosterone, and SHBG were measured. Bivariate and path analyses were performed to determine the relationship between variables. There was a negative association between dynorphin and kisspeptin, while NKB levels were not associated with kisspeptin. There was no direct association between kisspeptin and the LH/FSH ratio; interestingly, dynorphin was positively associated with the LH/FSH ratio in both bivariate and pathway analyses. AMH was positively correlated with the LH/FSH ratio in both analyses. Path analysis showed an association between dynorphin and kisspeptin levels in lean PCOS, while NKB was not correlated with kisspeptin. Furthermore, there was a correlation between AMH and the LH/FSH ratio, but kisspeptin levels did not show a direct significant relationship with the LH/FSH ratio. HOMA-IR was negatively associated with adiponectin levels and positively associated with leptin and FAI levels. In conclusion, AMH positively correlates with FAI levels and is directly associated with the LH/FSH ratio, showing its important role in neuroendocrinology in lean PCOS. From the path analysis, AMH was also an intermediary variable between HOMA-IR and FAI with the LH/FSH ratio. Interestingly, this study found a direct positive correlation between dynorphin and the LH/FSH ratio, while no association between kisspeptin and the LH/FSH ratio was found. Further research is needed to investigate AMH and dynorphin as potential therapeutic targets in the management of lean PCOS patients.

The kisspeptin system in and beyond reproduction: exploring intricate pathways and potential links between endometriosis and polycystic ovary syndrome

Endometriosis and polycystic ovary syndrome (PCOS) are two common female reproductive disorders with a significant impact on the health and quality of life of women affected. A novel hypothesis by evolutionary biologists suggested that these two diseases are inversely related to one another, representing a pair of diametrical diseases in terms of opposite alterations in reproductive physiological processes but also contrasting phenotypic traits. However, to fully explain the phenotypic features observed in women with these conditions, we need to establish a potential nexus system between the reproductive system and general biological functions. The recent discovery of kisspeptin as pivotal mediator of internal and external inputs on the hypothalamic-pituitary-gonadal axis has led to a new understanding of the neuroendocrine upstream regulation of the human reproductive system. In this review, we summarize the current knowledge on the physiological roles of kisspeptin in human reproduction, as well as its involvement in complex biological functions such as metabolism, inflammation and pain sensitivity. Importantly, these functions are known to be dysregulated in both PCOS and endometriosis. Within the evolving scientific field of "kisspeptinology", we critically discuss the clinical relevance of these discoveries and their potential translational applications in endometriosis and PCOS. By exploring the possibilities of manipulating this complex signaling system, we aim to pave the way for novel targeted therapies in these reproductive diseases.

Obesity-Related Hypogonadism in Women

Obesity-related hypogonadotropic hypogonadism is a well-characterized condition in men (termed male obesity-related secondary hypogonadism; MOSH); however, an equivalent condition has not been as clearly described in women. The prevalence of polycystic ovary syndrome (PCOS) is known to increase with obesity, but PCOS is more typically characterized by increased gonadotropin-releasing hormone (GnRH) (and by proxy luteinizing hormone; LH) pulsatility, rather than by the reduced gonadotropin levels observed in MOSH. Notably, LH levels and LH pulse amplitude are reduced with obesity, both in women with and without PCOS, suggesting that an obesity-related secondary hypogonadism may also exist in women akin to MOSH in men. Herein, we examine the evidence for the existence of a putative non-PCOS "female obesity-related secondary hypogonadism" (FOSH). We précis possible underlying mechanisms for the occurrence of hypogonadism in this context and consider how such mechanisms differ from MOSH in men, and from PCOS in women without obesity. In this review, we consider relevant etiological factors that are altered in obesity and that could impact on GnRH pulsatility to ascertain whether they could contribute to obesity-related secondary hypogonadism including: anti-Müllerian hormone, androgen, insulin, fatty acid, adiponectin, and leptin. More precise phenotyping of hypogonadism in women with obesity could provide further validation for non-PCOS FOSH and preface the ability to define/investigate such a condition.

Correlation of AMH with Cardiometabolic Markers in Polycystic Ovarian Syndrome: Systematic Review and Meta-Analysis

Objective

The purpose of this systematic review and meta-analysis was to determine whether there is a connection between polycystic ovarian syndrome (PCOS)-affected women's levels of the anti-Mullerian hormone (AMH) and certain cardiometabolic indicators.

Materials and Methods

To find pertinent recent research published between 2017 and 2023, a thorough search was done in PubMed. Studies were included if they looked into the relationship between PCOS-related women's AMH levels and cardiometabolic markers. To determine pooled effect estimates, data from the included studies were examined using random-effects models.

Results

Five papers were included in the meta-analysis since they satisfied the inclusion requirements. The meta-analysis found substantial positive relationships between AMH levels and markers of insulin resistance, fasting blood sugar levels, and dyslipidemia measures such as total cholesterol (SMD: 0.68, 95% confidence interval: 0.34-1.00, P < 0.001).

Conclusion

This systematic review and meta-analysis show that AMH levels in PCOS-affected women significantly positively correlate with markers of insulin resistance, fasting glucose levels, and dyslipidemia parameters. These findings imply that the pathogenesis of the cardiometabolic abnormalities seen in PCOS may include AMH. AMH may be used as a biomarker to estimate the cardiometabolic risk in PCOS-affected women, but more studies are required to determine its clinical applicability.

Diagnostic value of anti-Müllerian hormone combined with androgen-levels in Chinese patients with polycystic ovary syndrome

OBJECTIVE

To establish a cutoff level of AMH which could help for the diagnosis of PCOS, to investigate the predictive value of AMH combined with androgens in Chinese women to diagnose PCOS.

MATERIALS AND METHODS

This is a prospective case control study, 550 women recruited (aged 20-40 years), in which 450 PCOS women recruited according to the Rotterdam criteria and 100 non-PCOS women in the control group were from the women for the pregnancy preparation examination. AMH were measured by the Elecsys AMH Plus immunoassay. Androgens and other sex hormone were measured. The validity of AMH toward the diagnosis of PCOS, or AMH combined with total testosterone, free testosterone, bioavailable testosterone and androstenedione was estimated by receiver operating characteristic (ROC)curves, and correlations between paired variables was estimated by Spearman's rank correlation coefficient.

RESULTS

The cutoff value of AMH in Chinese reproductive-age women with PCOS is 4.64 ng/mL, AUC under the curve is 0.938, with 81.6% sensitivity, and 92.0% specificity. Total testosterone, free testosterone, bioactive testosterone, and androstenedione are significantly higher in women with PCOS of reproductive age than in controls. The combination of AMH and free testosterone resulted in a higher AUC of 94.8%, with higher sensitivity (86.1%) and excellent specificity (90.3%) for the prediction of PCOS.

CONCLUSION

The Elecsys AMH Plus immunoassay, with a cutoff of 4.64 ng/mL, is a robust method for identifying PCOM to aid in PCOS diagnosis. The combination of AMH and free testosterone resulted in a higher AUC of 94.8% for the diagnose of PCOS.

Paxillin knockout in mouse granulosa cells increases fecundity†

Paxillin is an intracellular adaptor protein involved in focal adhesions, cell response to stress, steroid signaling, and apoptosis in reproductive tissues. To investigate the role of paxillin in granulosa cells, we created a granulosa-specific paxillin knockout mouse model using Cre recombinase driven by the Anti-Müllerian hormone receptor 2 gene promoter. Female granulosa-specific paxillin knockout mice demonstrated increased fertility in later reproductive age, resulting in higher number of offspring when bred continuously up to 26 weeks of age. This was not due to increased numbers of estrous cycles, ovulated oocytes per cycle, or pups per litter, but this was due to shorter time to pregnancy and increased number of litters in the granulosa-specific paxillin knockout mice. The number of ovarian follicles was not significantly affected by the knockout at 30 weeks of age. Granulosa-specific paxillin knockout mice had slightly altered estrous cycles but no difference in circulating reproductive hormone levels. Knockout of paxillin using clustered regularly interspaced short palindromic repeat-associated protein 9 (CRISPR-Cas9) in human granulosa-derived immortalized KGN cells did not affect cell proliferation or migration. However, in cultured primary mouse granulosa cells, paxillin knockout reduced cell death under basal culture conditions. We conclude that paxillin knockout in granulosa cells increases female fecundity in older reproductive age mice, possibly by reducing granulosa cell death. This study implicates paxillin and its signaling network as potential granulosa cell targets in the management of age-related subfertility.

[Neuroendocrine features of the pathogenesis of polycystic ovary syndrome (literature review)]

Polycystic ovary syndrome (PCOS) is one of the most pressing problems in endocrine gynecology. The main signs of the disease are hyperandrogenism, menstrual and/or ovulatory dysfunction, and polycystic ovarian structure according to ultrasound. Women with PCOS are at risk for developing metabolic syndrome, type 2 diabetes, cardiovascular disease, and endometrial cancer. In this connection, the pathogenetic mechanisms of the occurrence of this syndrome are continuously studied and new methods of treatment are being sought. PCOS is characterized by a wide range of various disorders of the neuroendocrine regulation of the reproductive system. The main focus of the review is aimed at summarizing information about the etiological role of neuropeptides and neurotransmitters, such as phoenixin, galanins, orexins, GABA, in the pathophysiology of PCOS and about the possibility of their use for diagnostic and therapeutic purposes. In recent decades, the interest of scientists has been focused on the study of KNDy neurons, because it is the kisspeptin synthesized by them that is one of the main regulators of the hypothalamic-pituitary-ovarian axis. This article discusses data on the significance of KNDy neurons in the pathogenesis of the syndrome. Information is provided on the effect of elevated levels of androgens and anti-Müllerian hormone on GnRH neurons. Also analyzed are studies on functional and structural disorders in the hypothalamus in PCOS. Literature search was carried out in national (eLibrary, CyberLeninka.ru) and international (PubMed, Cochrane Library) databases in Russian and English. The priority was free access to the full text of articles. The choice of sources was prioritized for the period from 2018 to 2023.However, taking into account the insufficient knowledge of the chosen topic, the choice of sources dates back to 1998.

Prevalence and characteristics of polycystic ovarian syndrome in patients with bipolar disorder

BACKGROUND

Bipolar disorder (BD) is frequently accompanied by endocrine disturbances. We compared the prevalence of polycystic ovary syndrome (PCOS) and related reproductive disorders between drug-naïve BD patients and matched healthy controls (HCs) and between drug-naïve BD patients and BD patients with long-term medication, as well as the clinical metabolic correlates among BD patients.

METHODS

72 drug-naïve BD patients, 98 HCs, and 72 BD patients with long-term medication were recruited in the study. Menstruation was recorded, reproductive hormone levels and metabolic indicators were measured, and a pelvic ultrasound examination was performed via transvaginal sensor for each participant. PCOS was defined using the Rotterdam criteria.

RESULTS

After controlling for demographic variables, drug-naïve BD patients presented higher rates of PCOS than the HCs (OR: 3.02, 95 % CI: 1.09-8.36). Regression analysis showed that long-term treatment with valproate (OR: 3.89, 95 % CI: 1.13-13.37), age (OR: 0.37, 95 % CI: 0.14-0.95), and insulin resistance index (OR: 1.73, 95 % CI: 1.10-12.71) were correlated with PCOS in BD patients.

CONCLUSIONS

Drug-naïve BD patients are susceptible to developing PCOS, and valproate is correlated with increased occurrence and development of PCOS. Therefore, PCOS in BD patients, especially those who use valproate, needs to be investigated and monitored closely by medical personnel.

Overactivation of GnRH neurons is sufficient to trigger polycystic ovary syndrome-like traits in female mice

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder leading to anovulatory infertility. Abnormalities in the central neuroendocrine system governed by gonadotropin-releasing hormone (GnRH) neurons might be related to ovarian dysfunction in PCOS, although the link in this disordered brain-to-ovary communication remains unclear. Here, we manipulated GnRH neurons using chemogenetics in adult female mice to unveil whether chronic overaction of these neurons would trigger PCOS-like hormonal and reproductive impairments.

METHODS

We used adult Gnrh1cre female mice to selectively target and express the designer receptors exclusively activated by designer drugs (DREADD)-based chemogenetic tool hM3D(Gq) in hypophysiotropic GnRH neurons. Chronic chemogenetic activation protocol was carried out with clozapine N-oxide (CNO) i.p. injections every 48 h over a month. We evaluated the reproductive and hormonal profile before, during, and two months after chemogenetic manipulations.

FINDINGS

We discovered that the overactivation of GnRH neurons was sufficient to disrupt reproductive cycles, promote hyperandrogenism, and induce ovarian dysfunction. These PCOS features were detected with a long-lasting neuroendocrine dysfunction through abnormally high luteinizing hormone (LH) pulse secretion. Additionally, the GnRH-R blockade prevented the establishment of long-term neuroendocrine dysfunction and androgen excess in these animals.

INTERPRETATION

Taken together, our results show that hyperactivity of hypothalamic GnRH neurons is a major driver of reproductive and hormonal impairments in PCOS and suggest that antagonizing the aberrant GnRH signaling could be an efficient therapeutic venue for the treatment of PCOS.

FUNDING

European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement n◦ 725149).

Polycystic ovary syndrome: pathophysiology and therapeutic opportunities

Polycystic ovary syndrome is characterised by excessive levels of androgens and ovulatory dysfunction, and is a common endocrine disorder in women of reproductive age. Polycystic ovary syndrome arises as a result of polygenic susceptibility in combination with environmental influences that might include epigenetic alterations and in utero programming. In addition to the well recognised clinical manifestations of hyperandrogenism and ovulatory dysfunction, women with polycystic ovary syndrome have an increased risk of adverse mental health outcomes, pregnancy complications, and cardiometabolic disease. Unlicensed treatments have limited efficacy, mostly because drug development has been hampered by an incomplete understanding of the underlying pathophysiological processes. Advances in genetics, metabolomics, and adipocyte biology have improved our understanding of key changes in neuroendocrine, enteroendocrine, and steroidogenic pathways, including increased gonadotrophin releasing hormone pulsatility, androgen excess, insulin resistance, and changes in the gut microbiome. Many patients with polycystic ovary syndrome have high levels of 11-oxygenated androgens, with high androgenic potency, that might mediate metabolic risk. These advances have prompted the development of new treatments, including those that target the neurokinin-kisspeptin axis upstream of gonadotrophin releasing hormone, with the potential to lessen adverse clinical sequelae and improve patient outcomes.

The roles of anti-Müllerian hormone in breast cancer

Anti-Müllerian hormone (AMH) is produced and secreted by granulosa cells of growing follicles, and its main role is to inhibit the recruitment of primordial follicles, reduce the sensitivity of follicles to follicle-stimulating hormone (FSH), and regulate FSH-dependent preantral follicle growth. It has become an effective indicator of ovarian reserve in clinical practice. Research on AMH and its receptors in recent years has led to a better understanding of its role in breast cancer. AMH specifically binds to anti-Müllerian hormone receptor II (AMHRII) to activate downstream pathways and regulate gene transcription. Since AMHRII is expressed in breast cancer cells and triggers apoptosis, AMH/AMHRII may play an important role in the occurrence, treatment, and prognosis of breast cancer, which needs further research. The AMH level is a potent predictor of ovarian function after chemotherapy in premenopausal breast cancer patients older than 35 years, either for ovarian function injury or ovarian function recovery. Moreover, AMHRII has the potential to be a new marker for the molecular typing of breast cancer and a new target for breast cancer treatment, which may be a link in the downstream pathway after TP53 mutation.

Polycystic Ovary Syndrome: A Literature Review With a Focus on Diagnosis, Pathophysiology, and Management

In females with polycystic ovarian syndrome (PCOS), the most prevalent endocrine condition is chronic anovulation and hyperandrogenism. This illness influences females from conception to death, posing several risks to the health of a female, thus reducing the quality of life. It also increases the rates of mortality and morbidity. The first years of puberty are when PCOS symptoms first show. Menstrual irregularities, anovulation, and acne are features of both PCOS and typical puberty in females. There are many various phenotypes that fall under the same illness, so it is necessary to examine each one independently because they may need different treatments and result in different outcomes. Depending on the diagnostic criteria, approximately 6%-20% of females in the reproductive age group are believed to be affected by PCOS. As long as PCOS is still a syndrome, no single diagnostic indicator, such as hyperandrogenism or polycystic ovary (PCO), can be used to make a clinical diagnosis. The management of females with PCOS depends on the symptoms. These could include menstruation problems, androgen-related symptoms, or infertility caused by ovulatory disruption. In females with PCOS, anovulation is linked to low follicle-stimulating hormone (FSH) levels and a halt in antral follicle growth during the last stages of maturation. The condition may be treated surgically with laparoscopic ovarian drilling or medically with medications such as aromatase inhibitors, metformin, glucocorticoids, clomiphene citrate (CC), tamoxifen, or gonadotropins. Patients will experience different androgenic symptoms, such as hirsutism, acne, and/or baldness. Patients who appear with these troubling symptoms need to receive appropriate care. The review emphasizes the role it plays in the management of various conditions.

Insulin-like Growth Factor 1, Growth Hormone, and Anti-Müllerian Hormone Receptors Are Differentially Expressed during GnRH Neuron Development

Gonadotropin-releasing hormone (GnRH) neurons are key neuroendocrine cells in the brain as they control reproduction by regulating hypothalamic-pituitary-gonadal axis function. In this context, anti-Müllerian hormone (AMH), growth hormone (GH), and insulin-like growth factor 1 (IGF1) were shown to improve GnRH neuron migration and function in vitro. Whether AMH, GH, and IGF1 signaling pathways participate in the development and function of GnRH neurons in vivo is, however, currently still unknown. To assess the role of AMH, GH, and IGF1 systems in the development of GnRH neuron, we evaluated the expression of AMH receptors (AMHR2), GH (GHR), and IGF1 (IGF1R) on sections of ex vivo mice at different development stages. The expression of AMHR2, GHR, and IGF1R was assessed by immunofluorescence using established protocols and commercial antibodies. The head sections of mice were analyzed at E12.5, E14.5, and E18.5. In particular, at E12.5, we focused on the neurogenic epithelium of the vomeronasal organ (VNO), where GnRH neurons, migratory mass cells, and the pioneering vomeronasal axon give rise. At E14.5, we focused on the VNO and nasal forebrain junction (NFJ), the two regions where GnRH neurons originate and migrate to the hypothalamus, respectively. At E18.5, the median eminence, which is the hypothalamic area where GnRH is released, was analyzed. At E12.5, double staining for the neuronal marker ß-tubulin III and AMHR2, GHR, or IGF1R revealed a signal in the neurogenic niches of the olfactory and VNO during early embryo development. Furthermore, IGF1R and GHR were expressed by VNO-emerging GnRH neurons. At E14.5, a similar expression pattern was found for the neuronal marker ß-tubulin III, while the expression of IGF1R and GHR began to decline, as also observed at E18.5. Of note, hypothalamic GnRH neurons labeled for PLXND1 tested positive for AMHR2 expression. Ex vivo experiments on mouse sections revealed differential protein expression patterns for AMHR2, GHR, and IGF1R at any time point in development between neurogenic areas and hypothalamic compartments. These findings suggest a differential functional role of related systems in the development of GnRH neurons.

Subacute high-refined carbohydrate diet leads to abnormal reproductive control of the hypothalamic-pituitary axis in female rats

We previously reported that female rats placed on a diet containing refined carbohydrates (HCD) resulted in obesity and reproductive abnormalities, such as high serum LH concentration and abnormal ovarian function. However, the impacts at the hypothalamic-pituitary (HP) function, specifically regarding pathways linked to reproductive axis modulation are unknown. In this study, we assessed whether subacute feeding with HCD results in abnormal reproductive control in the HP axis. Female rats were fed with HCD for 15 days and reproductive HP axis morphophysiology was assessed. HCD reduced hypothalamic mRNA expression (Kiss1, Lepr, and Amhr2) and increased pituitary LHβ+ cells. These changes likely contribute to the increase in serum LH concentration observed in HCD. Blunted estrogen negative feedback was observed in HCD, with increased kisspeptin protein expression in the arcuate nucleus of the hypothalamus (ARH), lower LHβ+ cells and LH concentration in ovariectomized (OVX)+HCD rats. Thus, these data suggest that HCD feeding led to female abnormal reproductive control of HP axis.

Serum LH levels are associated to serum insulin and Anti-Müllerian hormone levels in women with both functional hypothalamic amenorrhoea and polycystic ovarian morphology

OBJECTIVE

The aim of the study was to investigate whether serum Luteinizing Hormone (LH) levels in women with Functional Hypothalamic Amenorrhoea (FHA) and Polycystic Ovarian Morphology (PCOM) are still associated to Body Mass Index (BMI) and/or serum insulin and/or Anti-Müllerian Hormone (AMH) levels using a larger population of FHA.

DESIGN

Retrospective observational study (2006-2020).

PARTICIPANTS

Data from 62 FHA patients were used for this study using strict criteria to define them.

MEASUREMENTS

Serum LH, FSH, 17-hydroxyprogesterone (17-OHP), dehydroepiandrosterone sulphate (DHEA-S), androstenedione, total testosterone, prolactin, Sex Hormone Binding Globulin (SHBG) and AMH levels were measured by immunoassay. To homogenize the AMH values, we converted those obtained after 2015. We defined PCOM with strict criteria: a follicle number per ovary (FNPO) ≥12 or ≥20 per ovary, depending on the date on which the assessment was carried out and the ultrasound device.

RESULTS

Forty-two percentage of our FHA population had PCOM. The PCOM+ group had significantly higher ranks of BMI (p = .024) and serum AMH levels (p = .0001) and significantly lower ranks of serum FSH levels (p = .002). LH was positively correlated with fasting insulin (p = .011) and with AMH (p = .035) in the PCOM+ group only but not with BMI. There was a positive correlation between LH and FSH in both groups.

CONCLUSION

Our study suggests that GnRH insufficiency in women with PCOM unravels some mechanisms of LH regulation that are poorly documented in the literature and may involve a direct pituitary effect, as suggested by our results with serum insulin and AMH levels.

AMH and other markers of ovarian function in patients with Turner syndrome - a single center experience of transition from pediatric to gynecological follow up

Turner syndrome (TS) is a chromosomal disorder that affects about 1 in 2500 female births and is characterized by the partial or complete absence of the second X chromosome. Depending on karyotype, TS is associated with primary ovarian insufficiency (POI). Approximately 50% of girls with a mosaic 45, X/46, XX karyotype may enter puberty spontaneously, but only 5-10% of women with TS achieve pregnancy without egg donation. In this review, we will evaluate the clinical use of markers of ovarian function in TS patients. Based on longitudinal studies of serum concentrations of reproductive hormones as well as ovarian morphology in healthy females and patients with TS, we will evaluate how they can be applied in a clinical setting. This is important when counseling patients and their families about future ovarian function essential for pubertal development and fertility. Furthermore, we will report on 20 years of experience of transition from pediatric to gynecological and adult endocrinological care in our center at Rigshospitalet, Copenhagen, Denmark.

AMH as part of the diagnostic PCOS workup in large epidemiological studies

OBJECTIVES

Previous studies have shown good correlation between polycystic ovarian morphology (PCOM) and serum anti-Müllerian hormone (AMH) levels. We evaluated the utility of AMH as a surrogate for PCOM as a part of the polycystic ovary syndrome (PCOS) diagnosis by describing how the use of different AMH cut-off values would change the prevalence of PCOS.

METHODS

A general population-based birth cohort study. Anti-Müllerian hormone concentrations were measured from serum samples taken at age 31 years (n = 2917) using the electrochemiluminescence immunoassay (Elecsys). Anti-Müllerian hormone data were combined with data on oligo/amenorrhoea and hyperandrogenism to identify women with PCOS.

RESULTS

The addition of AMH as a surrogate marker for PCOM increased the number of women fulfilling at least two PCOS features in accordance with the Rotterdam criteria. The prevalence of PCOS was 5.9% when using the AMH cut-off based on the 97.5% quartile (10.35 ng/mL) and 13.6% when using the recently proposed cut-off of 3.2 ng/mL. When using the latter cut-off value, the distribution of PCOS phenotypes A, B, C, and D was 23.9%, 4.7%, 36.6%, and 34.8%, respectively. Compared with the controls, all PCOS groups with different AMH concentration cut-offs showed significantly elevated testosterone (T), free androgen index (FAI), luteinizing hormone (LH), LH/follicle-stimulating hormone (FSH) ratio, body mass index (BMI), waist circumference, and homoeostatic model assessment of insulin resistance (HOMA-IR) values, as well as significantly decreased sex hormone-binding globulin (SHBG) values.

CONCLUSIONS

Anti-Müllerian hormone could be useful surrogate for PCOM in large data sets, where transvaginal ultrasound is not feasible, to aid the capturing of women with typical PCOS characteristics. Anti-Müllerian hormone measurement from archived samples enables retrospective PCOS diagnosis when combined with oligo/amenorrhoea or hyperandrogenism.

Durable contraception in the female domestic cat using viral-vectored delivery of a feline anti-Müllerian hormone transgene

Eighty percent of the estimated 600 million domestic cats in the world are free-roaming. These cats typically experience suboptimal welfare and inflict high levels of predation on wildlife. Additionally, euthanasia of healthy animals in overpopulated shelters raises ethical considerations. While surgical sterilization is the mainstay of pet population control, there is a need for efficient, safe, and cost-effective permanent contraception alternatives. Herein, we report evidence that a single intramuscular treatment with an adeno-associated viral vector delivering an anti-Müllerian hormone transgene produces long-term contraception in the domestic cat. Treated females are followed for over two years, during which transgene expression, anti-transgene antibodies, and reproductive hormones are monitored. Mating behavior and reproductive success are measured during two mating studies. Here we show that ectopic expression of anti-Müllerian hormone does not impair sex steroids nor estrous cycling, but prevents breeding-induced ovulation, resulting in safe and durable contraception in the female domestic cat.

A Review and Meta-Analysis of the Prevalence and Health Impact of Polycystic Ovary Syndrome Among Medical and Dental Students

Women currently comprise the majority of students graduating from medical school and face unique stressors not seen with their male counterparts. In particular, during their medical education, women with polycystic ovary syndrome (PCOS) experience symptoms of the disorder, which strongly impact both their academic and social lives. This in turn influences their academic and professional future. Although women as medical professionals, in general, are happy with their careers, awareness, and understanding on the part of medical educators will definitely be helpful to women medical students in their path to being successful medical professionals. The first objective of our current study is to find the prevalence of PCOS in medical and dental students. The second objective is to find the academic and health impacts of PCOS and what type of interventions are being adopted to relieve the symptoms. Using the keywords such as "PCOS," "medical students," and "dental students", the search engines PubMed, Embase, and Scopus were used to retrieve relevant articles published from 2020 to 2022. After removing the duplicates, 11 prospective cross-sectional studies were utilized for qualitative and quantitative analysis. The pooled prevalence of 2,206 female medical students diagnosed with PCOS was 24.7%. The students in the various studies were aware of their PCOS diagnosis and were taking therapeutic medications. The most common associated complications reported were BMI abnormalities, abnormal hair growth, and acne, along with other complications such as stress and poor academic and social life. The majority also had significant family histories of concurrent clinical conditions such as diabetes, hypertension, and other menstrual abnormalities. Considering the huge impact of PCOS, medical educators, policymakers, and all stakeholders should take proactive measures to accommodate students' needs and bridge the social gap. Special awareness of needed lifestyle changes should be a part of the medical education curriculum for an inclusive educational environment, as it will minimize the gender discrepancy in academic satisfaction and professional life.

Digenic Congenital Hypogonadotropic Hypogonadism Due to Heterozygous GNRH1 p.R31C and AMHR2 p.G445_L453del Variants

A 28-year-old man with congenital hypogonadotropic hypogonadism (CHH) was found to be heterozygous for the GNRH1 p.R31C mutation, reported in the literature as pathogenic and dominant. The same mutation was found in his son at birth, but the testing of the infant at 64 days confirmed the hormonal changes associated with minipuberty. This led to further genetic sequencing of the patient and his son, which found a second variant, AMHR2 p.G445_L453del, in the heterozygous form, reported as pathogenic in the patient but not in his son. This suggests a digenic cause of the patient's CHH. Together, these mutations are postulated to contribute to CHH by the lack of anti-Müllerian hormone (AMH) signalling, leading to the impaired migration of gonadotrophin releasing hormone (GnRH) neurons, the lack of the AMH effect on GnRH secretion, and altered GnRH decapeptide with reduced binding to GnRH receptors. This led us to the conclusion that the observed GNRH1 mutation in the heterozygous state is not certain to be dominant or, at least, exhibits incomplete penetrance and variable expressivity. This report also emphasises the opportunity afforded by the time window of minipuberty in assessing the inherited genetic disorders of hypothalamic function.

Metformin promotes female germline stem cell proliferation by upregulating Gata-binding protein 2 with histone β-hydroxybutyrylation

BACKGROUND

Metformin as a first-line clinical anti-diabetic agent prolongs the lifespan of model animals and promotes cell proliferation. However, the molecular mechanisms underlying the proliferative phenotype, especially in epigenetics, have rarely been reported. The aim of this study was to investigate the physiological effects of metformin on female germline stem cells (FGSCs) in vivo and in vitro, uncover β-hydroxybutyrylation epigenetic modification roles of metformin and identify the mechanism of histone H2B Lys5 β-hydroxybutyrylation (H2BK5bhb) in Gata-binding protein 2 (Gata2)-mediated proliferation promotion of FGSCs.

METHODS

The physiological effects of metformin were evaluated by intraperitoneal injection and histomorphology. The phenotype and mechanism studies were explored by cell counting, cell viability, cell proliferation assay and protein modification omics, transcriptomics, chromatin immunoprecipitation sequencing in FGSCs in vitro.

RESULTS

We found that metformin treatment increased the number of FGSCs, promoted follicular development in mouse ovaries and enhanced the proliferative activity of FGSCs in vitro. Quantitative omics analysis of protein modifications revealed that H2BK5bhb was increased after metformin treatment of FGSCs. In combination with H2BK5bhb chromatin immunoprecipitation and transcriptome sequencing, we found that Gata2 might be a target gene for metformin to regulate FGSC development. Subsequent experiments showed that Gata2 promoted FGSC proliferation.

CONCLUSION

Our results provide novel mechanistic understanding of metformin in FGSCs by combining histone epigenetics and phenotypic analyses, which highlight the role of the metformin-H2BK5bhb-Gata2 pathway in cell fate determination and regulation.

Hypothalamic neuroglial plasticity is regulated by anti-Müllerian hormone and disrupted in polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common reproductive-endocrine disorder affecting between 5 and 18% of women worldwide. An elevated frequency of pulsatile luteinizing hormone (LH) secretion and higher serum levels of anti-Müllerian hormone (AMH) are frequently observed in women with PCOS. The origin of these abnormalities is, however, not well understood.

METHODS

We studied brain structure and function in women with and without PCOS using proton magnetic resonance spectroscopy (MRS) and diffusion tensor imaging combined with fiber tractography. Then, using a mouse model of PCOS, we investigated by electron microscopy whether AMH played a role on the regulation of hypothalamic structural plasticity.

FINDINGS

Increased AMH serum levels are associated with increased hypothalamic activity/axonal-glial signalling in PCOS patients. Furthermore, we demonstrate that AMH promotes profound micro-structural changes in the murine hypothalamic median eminence (ME), creating a permissive environment for GnRH secretion. These include the retraction of the processes of specialized AMH-sensitive ependymo-glial cells called tanycytes, allowing more GnRH neuron terminals to approach ME blood capillaries both during the run-up to ovulation and in a mouse model of PCOS.

INTERPRETATION

We uncovered a central function for AMH in the regulation of fertility by remodeling GnRH terminals and their tanycytic sheaths, and provided insights into the pivotal role of the brain in the establishment and maintenance of neuroendocrine dysfunction in PCOS.

FUNDING

INSERM (U1172), European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement n° 725149), CHU de Lille, France (Bonus H).

Potential Role of Anti-Müllerian Hormone in Regulating Seasonal Reproduction in Animals: The Example of Males

Seasonal reproduction is a survival strategy by which animals adapt to environmental changes to improve their fitness. Males are often characterized by a significantly reduced testicular volume, indicating that they are in an immature state. Although many hormones, including gonadotropins, have played a role in testicular development and spermatogenesis, research on other hormones is insufficient. The anti-Müllerian hormone (AMH), which is a hormone responsible for inducing the regression of Müllerian ducts involved in male sex differentiation, was discovered in 1953. Disorders in AMH secretion are the main biomarkers of gonadal dysplasia, indicating that it may play a crucial role in reproduction regulation. A recent study has found that the AMH protein is expressed at a high level during the non-breeding period of seasonal reproduction in animals, implying that it may play a role in restricting breeding activities. In this review, we summarize the research progress on the AMH gene expression, regulatory factors of the gene's expression, and its role in reproductive regulation. Using males as an example, we combined testicular regression and the regulatory pathway of seasonal reproduction and attempted to identify the potential relationship between AMH and seasonal reproduction, to broaden the physiological function of AMH in reproductive suppression, and to provide new ideas for understanding the regulatory pathway of seasonal reproduction.

AMH producing purely cystic virilizing adult granulosa cell tumor in 17 years old girl: a case report and review of literatures

BACKGROUND

Androgen-producing granulosa cell tumor in adolescent girl is rare condition and clinical characteristics are not fully elucidated.

CASE PRESENTATION

Seventeen years old girl complained of secondary amenorrhea was referred to our out-patient consultation. Markedly elevated serum testosterone, LH, and AMH levels were noted. Mild hirsutism and clitoromegaly were presented. Transabdominal ultrasonography and MRI revealed cystic mass occupied pelvic cavity probably originated from left ovary. Right ovary showed polycystic appearance. Laparoscopic left ovarian cystectomy was performed. After the surgery, her menstruation resumed along with normalized hormonal parameters, and clinical hyperandrogenism were improved. Since the scarcity of cellular lining of inner cyst wall, definitive pathological diagnosis was difficult. After the consultation with gynecological pathologist, the tumor was diagnosed as sex cord stromal tumor, highly suspicious for adult granulosa cell tumor. Residual left salpingo-oophorectomy was performed by additional laparoscopic surgery. Her serum testosterone and AMH levels were remained low with regular menstrual cycles and no evidence of recurrence.

CONCLUSIONS

Androgen-producing cystic granulosa cell tumor is rare gynecological disorders, which need both gynecologic oncological and endocrinological approach. Its clinical manifestations may bring some clues to the pathogenesis of ovulatory dysfunctions, such as polycystic ovary syndrome.

The Role of Serum Anti-Mullerian Hormone Measurement in the Diagnosis of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrinological disorder in women with significant reproductive, metabolic, and psychological health implications. The lack of a specific diagnostic test poses challenges in making the diagnosis of PCOS, resulting in underdiagnosis and undertreatment. Anti-Mullerian hormone (AMH) synthesized by the pre-antral and small antral ovarian follicles appears to play an important role in the pathophysiology of PCOS, and serum AMH levels are often elevated in women with PCOS. The aim of this review is to inform the possibility of utilizing anti-Mullerian hormone either as a diagnostic test for PCOS or as an alternative diagnostic criterion in place of polycystic ovarian morphology, hyperandrogenism, and oligo-anovulation. Increased levels of serum AMH correlate highly with PCOS, polycystic ovarian morphology, hyperandrogenism, and oligo/amenorrhea. Additionally, serum AMH has high diagnostic accuracy as an isolated marker for PCOS or as a replacement for polycystic ovarian morphology.

AMH inhibits androgen production in human theca cells

Both excessive ovarian production of AMH and androgen are important features of polycystic ovary syndrome (PCOS). Present study aimed to explore the direct effect of AMH on androgen production in human theca cells. Primary cultured human theca cells were treated with AMH, an ALK2 (the BMP type 1 receptor) inhibitor and an ALK5 (the TGFβ type 1 receptor) inhibitor. AMH significantly suppresses the expression of the androgen synthesis-related enzyme CYP17A1 and reduces the production of androstenedione and testosterone in normal human theca cells and PCOS theca cells. Inhibitors of ALK2/3 and ALK5 antagonize the effect of AMH on the expression of CYP17A1. Although both ALK5 and ALK2 interact with AMHR2 in the presence of AMH, AMH activated neither TGFβR-Smads (Smad 2/3) nor BMPR-Smads (Smad 1/5/8). Our data suggested that AMH suppresses androgen synthesis-related enzyme CYP17A1 expression and inhibits androgen production in human theca cells, which process may be mediated by ALK2 and ALK5.

Anti-Mullerian Hormone-Based Phenotyping Identifies Subgroups of Women with Polycystic Ovary Syndrome with Differing Clinical and Biochemical Characteristics

Even though polycystic ovary syndrome (PCOS) was originally defined as "amenorrhea associated with bilateral polycystic ovaries", women without PCO morphology can be included in this diagnosis. This may contribute to the clinical heterogeneity seen in PCOS. Serum anti-Mullerian hormone (AMH) correlates with the number of ovarian cysts. We investigated whether phenotyping based on serum AMH can distinguish subgroups of PCOS with different clinical and biochemical characteristics. The electronic medical records of 108 women with PCOS (Rotterdam criteria) were reviewed. The serum AMH value correlated inversely (0.03 < p < 0.0001) with age, weight, and BMI values and directly with serum total testosterone (T), free T, and bioavailable T values. When divided into quartiles based on serum AMH values, the women in the highest quartile (AMH: 18.5 ± 9.9 ng/mL; n = 27) had lower BMI (29.4 ± 6.9 vs. 34.0 ± 10.6-36.7 ± 7.2 kg/m²) but higher total T (51.3 ± 27.2 vs. 26.5 ± 10.4-35.1 ± 16.3 ng/dL), free T (7.7 ± 6.0 vs. 4.4 ± 2.3-5.7 ± 3.2 ng/dL), and bioavailable T (22.1 ± 17.0 vs. 12.2 ± 6.6-16.5 ± 8.7 ng/dL) values. The combination of high AMH and high testosterone values may point to the ovaries and reproductive etiology for PCOS in this subgroup. Thus, AMH-based phenotyping may provide a practical and cost-effective tool to explore the heterogeneity in PCOS.

Magnetic Resonance Imaging, a New Tool for Neuroendocrine Research in Sheep

Magnetic resonance imaging (MRI) brain analysis is used in rodents and for clinical investigation in humans, and it becomes also possible now for large animal models studies. Specific facilities are available with clinical scanners and benefit to neuroendocrine investigations in sheep. Sheep has a large gyrencephalic brain and its organization is very similar to primates and human, and among physiological regulations, oestrous cycle of the ewes is similar to women. Therefore, this animal is a good model for preclinical researches using MRI, as illustrated with steroids impact on the brain. New data were obtained concerning the effect of sexual steroids on neuronal networks involved in the control of reproduction and in the influence of sexual steroids on cognition. In addition to the importance of such data for understanding the role of these hormones on brain functions, they give new insights to consider the sheep as a powerful model for preclinical studies in the field of neuroendocrinology. These points are discussed in this short review.

AMH concentrations in infancy and mid-childhood predict ovarian activity in adolescence: A long-term longitudinal study of healthy girls

BACKGROUND

Anti-Müllerian hormone (AMH) is produced by granulosa cells in small growing ovarian follicles. In adult women, serum concentrations of AMH reflect the ovarian reserve of resting primordial follicles, and low AMH is associated with risk of early menopause. In contrast, patients with polycystic ovary syndrome (PCOS) have elevated AMH. The primary aim of this study was to evaluate the individual tracking of serum AMH concentrations, as well as whether AMH in early childhood reflects ovarian activity in adolescence.

METHODS

In this large longitudinal study of healthy girls were examined from infancy to adolescence (1997-2019) including physical examination, assessment of serum concentrations of reproductive hormones (in infancy, median age 0.3 yrs; mid-childhood, 7.2 yrs; puberty, 11.3 yrs; and adolescence, 15.9 yrs), transabdominal ultrasound (TAUS, puberty and adolescence) and magnetic resonance imaging (MRI, puberty) of the ovaries.

FINDINGS

Each girl maintained her relative AMH concentration (expressed as standard deviation (SD) scores) over time; mean variation of individual age adjusted AMH concentrations was 0.56 ± 0.31 SD.Serum concentrations of AMH in adolescence correlated with AMH in infancy and childhood; infancy: r = 0.347; mid-childhood: r = 0.637; puberty: r = 0.675, all p < 0.001.AMH correlated negatively with FSH concentrations in all age groups (infancy: r = -0.645, p < 0.001; mid-childhood: r = -0.222, p < 0.001; puberty: r = -0.354, p < 0.001; adolescence: n = 275, r = -0.175, p = 0.004).Serum AMH concentrations in mid-childhood correlated with the number of follicles in puberty (TAUS and MRI) as well as in adolescence (TAUS); e.g. total number of follicles: TAUS puberty (r = 0.607), MRI puberty (r = 0.379), TAUS adolescence (r = 0.414), all p < 0.001.AMH concentration in infancy as well as in mid-childhood predicted low AMH (<10 pmol/L) in adolescence; AMH infancy <7.5 pmol/L as predictor of low AMH in adolescence: sensitivity 0.71, specificity 0.70, AUC 0.759; AMH mid-childhood < 8.4 pmol/L as predictor of low AMH in adolescence: sensitivity 0.88, specificity 0.87, AUC 0.949.Girls with high serum AMH concentration in mid-childhood (AMH >30.0 pmol/L vs. other girls) had higher adolescent LH (median 4.53 vs. 3.29 U/L p = 0.041), LH/FSH ratio (1.00 vs 0.67, p = 0.019), testosterone (1.05 vs 0.81 nmol/L, p = 0.005), total number of follicles (23 vs. 19, p = 0.004), and higher prevalence of irregular cycles (10/15 = 67% vs. 28/113 = 25%, p = 0.002).

INTERPRETATION

The present findings suggest remarkably stable ovarian activity from small growing follicles in healthy girls, supporting AMH in early life as a useful clinical tool to predict future ovarian activity.

FUNDING

The work was supported by The Center on Endocrine Disruptors (CeHoS) under The Danish Environmental Protection Agency and The Ministry of Environment and Food (grant number: MST-621-00 065), the EU (QLK4-CT1999-01422; QLK4-2001-00269), the Novo Nordisk Foundation and The Danish Ministry of Science Technology and Innovation (2107-05-0006). A.S.B. is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - 464240267. KM receives honoraria from Novo Nordisk A/S for teaching at the Danish annual postgraduate course of pituitary diseases.

Clinical Utilities of Anti-Müllerian Hormone

The anti-Müllerian hormone (AMH) plays an essential role in sex determination in early embryonic development. Through a series of sequential steps that follows inheriting an XY chromosome, Sertoli cell differentiation upregulates the expression of AMH-suppressing Müllerian duct development and maintains the AMH at a high level until puberty. In females, the AMH is produced by granulosa cells of follicles beginning in the second half of fetal life and continues through adulthood, with a steady decline through the reproductive years and severe decline at menopause, until levels eventually become undetectable. The AMH is essential for the regulation of follicular maturation via the recruitment of primordial follicles throughout folliculogenesis. AMH serum concentration in women strongly correlates with ovarian reserve quantity and reflects ovulation potential. Because the AMH is expressed almost exclusively by growing follicles before FSH-dependent selection, it commonly serves as a marker for ovarian function in various clinical situations, including in the diagnosis and pathogenesis of polycystic ovarian syndrome, artificial reproductive technology, and predictions of menopause or premature ovarian failure.

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.

Deconstructing a Syndrome: Genomic Insights Into PCOS Causal Mechanisms and Classification

Polycystic ovary syndrome (PCOS) is among the most common disorders in women of reproductive age, affecting up to 15% worldwide, depending on the diagnostic criteria. PCOS is characterized by a constellation of interrelated reproductive abnormalities, including disordered gonadotropin secretion, increased androgen production, chronic anovulation, and polycystic ovarian morphology. It is frequently associated with insulin resistance and obesity. These reproductive and metabolic derangements cause major morbidities across the lifespan, including anovulatory infertility and type 2 diabetes (T2D). Despite decades of investigative effort, the etiology of PCOS remains unknown. Familial clustering of PCOS cases has indicated a genetic contribution to PCOS. There are rare Mendelian forms of PCOS associated with extreme phenotypes, but PCOS typically follows a non-Mendelian pattern of inheritance consistent with a complex genetic architecture, analogous to T2D and obesity, that reflects the interaction of susceptibility genes and environmental factors. Genomic studies of PCOS have provided important insights into disease pathways and have indicated that current diagnostic criteria do not capture underlying differences in biology associated with different forms of PCOS. We provide a state-of-the-science review of genetic analyses of PCOS, including an overview of genomic methodologies aimed at a general audience of non-geneticists and clinicians. Applications in PCOS will be discussed, including strengths and limitations of each study. The contributions of environmental factors, including developmental origins, will be reviewed. Insights into the pathogenesis and genetic architecture of PCOS will be summarized. Future directions for PCOS genetic studies will be outlined.

Deciphering the Roles & Regulation of Estradiol Signaling during Female Mini-Puberty: Insights from Mouse Models

Mini-puberty of infancy is a short developmental phase occurring in humans and other mammals after birth. In females, it corresponds to transient and robust activation of the hypothalamo-pituitary-ovarian (HPO) axis revealed by high levels of gonadotropin hormones, follicular growth, and increased estradiol production by the ovary. The roles of estradiol signaling during this intriguing developmental phase are not yet well known, but accumulating data support the idea that it aids in the implementation of reproductive function. This review aims to provide in-depth information on HPO activity during this particular developmental phase in several mammal species, including humans, and to propose emerging hypotheses on the putative effect of estradiol signaling on the development and function of organs involved in female reproduction.

Circulating Anti-Müllerian hormone in a cohort-study of women with severe obesity with and without polycystic ovary syndrome and the effect of a one-year weight loss intervention

BACKGROUND

Women with polycystic ovary syndrome (PCOS) have high circulating anti-Müllerian hormone (AMH) levels which is correlated with antral follicle count and polycystic ovarian morphology and negatively correlated with body mass index (BMI). Moreover, diet-induced weight loss in women with PCOS and overweight or obesity, reduce or normalize AMH-levels. There is, however, no previous study investigating the circulating AMH levels in women with severe obesity and how a structured diet-induced weight loss program affects circulating AMH levels in these women. Therefore, this study aims to investigate circulating AMH levels in a population of women with severe obesity (BMI ≥ 35 kg/m²) with and without PCOS, as diagnosed by the NIH-criteria, and to investigate the effect of a one-year weight loss program with a very low-energy diet (VLED) on circulating levels of AMH.

METHODS

In a prospective cohort-study, were 246 women with severe obesity were screened for PCOS diagnosis with the NIH-criteria, circulating AMH and anthropometry were measured at baseline and after a 12-month weight loss intervention with very low-energy diet (VLED).

RESULTS

Mean BMI was 39.9 ± 4.7 (PCOS), 39.6 ± 4.3 (non-PCOS) P = 0.960. Circulating AMH was higher in women with PCOS (5.47 ± 4.89 µg/L) compared with non-PCOS (2.66 ± 3.71 µg/L) P < 0.001 and was positively correlated with circulating total testosterone in both groups. Next, we performed ROC-analyses, and show that circulating AMH could not discriminate women with PCOS and severe obesity from non-PCOS women with severe obesity. Finally, a one-year weight reduction program does not affect circulating AMH levels despite significant weight loss neither in women with PCOS, nor without PCOS and severe obesity.

CONCLUSION

Women with severe obesity and PCOS have elevated levels of circulating AMH compared to women without the syndrome. AMH-levels could not discriminate women with PCOS from non-PCOS because of low sensitivity and specificity. Significant weight loss was not associated with changes in circulating AMH levels, neither in women with, nor without PCOS and severe obesity. These results imply that in women with severe obesity, a greater weight loss may be needed to improve reproductive features, independent of PCOS diagnosis.

TRIAL REGISTRATION NUMBER

Clinical trial.gov: NCT01319162.

Role of anti-Mullerian hormone in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common gynecological endocrine disorders affecting up to 10% of all females in their reproductive age, and its cause of onset is still elusive. A spectrum of recent research reflected diverse associations between increased plasma level of anti-Mullerian hormone (AMH) and different clinical features of PCOS. Since AMH levels reflect the pool of growing follicles that potentially can ovulate, it can be stated that serum AMH levels can be used to assess the “functional ovarian reserve,” rather mentioning it as the “ovarian reserve.” AMH also appears to be a premier endocrine parameter for the assessment of atrophied ovarian follicular pool in response to age of individuals. AMH hinders the follicular development as well as the follicular recruitment and ultimately resulting in follicular arrest which is the key pathophysiologic condition for the onset of PCOS. Furthermore, FSH-induced aromatase activity remains inhibited by AMH that aids emergence of other associated clinical signs of PCOS, such as excess androgen, followed by insulin resistance among the PCOS individuals. Given the versatile association of AMH with PCOS and scarcity in literature explaining the underling mechanisms how AMH relates with PCOS, this review article will discuss the roles of AMH in the pathogenesis of PCOS which may introduce a new era in treatment approach of PCOS.

Update on Animal Models of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a complex disease affecting up to 15% of women of reproductive age. Women with PCOS suffer from reproductive dysfunctions with excessive androgen secretion and irregular ovulation, leading to reduced fertility and pregnancy complications. The syndrome is associated with a wide range of comorbidities including type 2 diabetes, obesity, and psychiatric disorders. Despite the high prevalence of PCOS, its etiology remains unclear. To understand the pathophysiology of PCOS, how it is inherited, and how to predict PCOS, and prevent and treat women with the syndrome, animal models provide an important approach to answering these fundamental questions. This minireview summarizes recent investigative efforts on PCOS-like rodent models aiming to define underlying mechanisms of the disease and provide guidance in model selection. The focus is on new genetic rodent models, on a naturally occurring rodent model, and provides an update on prenatal and peripubertal exposure models.

Loss of Anti-Müllerian Hormone Signaling in Mice Affects Trabecular Bone Mass in a Sex- and Age-Dependent Manner

Ovariectomy-induced osteoporosis in mice results from an abrupt loss of ovarian sex steroids. Anti-Müllerian hormone knockout (AMHKO) mice show a gradual but accelerated ovarian aging, and therefore may better resemble osteoporosis following natural menopause. To study the impact of AMH signaling deficiency on bone, we compared trabecular and cortical bone parameters in 2-, 4-, 10-, and 16-month-old male and female wild-type (WT), AMHKO, and AMH type II receptor knockout (MRKI) mice using micro computed tomography (microCT). Goldner's staining was performed to confirm the observed bone phenotype. Both male and female AMHKO and MRKI mice showed age-dependent loss of trabecular bone (P < 0.001). However, reproductive-aged female AMHKO and MRKI mice had higher BV/TV compared with WT (P < 0.001), coinciding with increased growing follicle numbers (P < 0.05) and increased estrus inhibin B levels (AMHKO: P < 0.001; MRKI: P < 0.05) but normal inhibin A, estrogen, and progesterone levels. In aged female AMHKO and MRKI mice BV/TV did not differ from WT mice due to greater trabecular bone loss between 10 and 16 months compared with WT mice. At these ages, AMHKO and MRKI mice had reduced growing follicle numbers (P < 0.05) and reduced inhibin B levels (P < 0.001). At age 10 months, female MRKI mice had increased cortical bone parameters compared with WT mice (P < 0.01). Bone parameters of male AMHKO and MRKI mice did not differ from male WT mice. In conclusion, AMH signaling deficiency results in a sex- and age-dependent effect on predominantly trabecular bone. Our results further suggest that reproductive hormones beyond estrogen may contribute to bone homeostasis.

An update of polycystic ovary syndrome: causes and therapeutics options

Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by menstrual irregularities, chronic anovulation, hirsutism, androgenic alopecia, and acne. At diagnosis, patients can with different manifestations according to the disease phenotype, patient’s age, and lifestyle. However, most patients pursue medical care because of the clinical symptoms of PCOS, such as hyperandrogenism, menstrual irregularities and infertility. Recent studies have shown that PCOS is associated with 80% of anovulatory infertility; however, the precise mechanism of PCOS-induced anovulation is still undetermined. The treatment strategies of PCOS are symptomatic depending mainly on the desired goals and clinical benefits. Life style intervention is still the first line treatment option for overweight females seeking pregnancy. In addition, there are many pharmacological agents that could be added to induce ovulation such as metformin, and clomiphene citrate. Nowadays, many patients preferred to use some herbal medicine that was proved to have potential therapeutic benefits in many studies in the management of PCOS. The purpose of this review was to discuss PCOS-induced infertility and the available therapeutic options as well as the impact of COVID-19 infection on the success of fertility attempts. To address this purpose, Pubmed, Scopus, EMBASE and Google databases were searched for studies discussing PCOS-induced infertility. The literature search revealed the proper therapeutic plans to treat PCOS-induced infertility, and that treatment should be modified according to patient’s complaints, reproductive desires, and disease phenotypes. In conclusion, the use of specific therapeutic agents and patients’ adherence to lifestyle interventions could help patients recover their reproductive and metabolic health.

Anti-Müllerian Hormone and Polycystic Ovary Syndrome in Women and Its Male Equivalent

This article reviews the main findings on anti-Müllerian hormone (AMH) and its involvement in the pathogenesis of polycystic ovary syndrome (PCOS) and its male equivalent. In women, AMH is produced by granulosa cells from the mid-fetal life to menopause and is a reliable indirect marker of ovarian reserve. AMH protects follicles from atresia, inhibits their differentiation in the ovary, and stimulates gonadotrophin-releasing hormone neurons pulsatility. AMH overexpression in women with PCOS likely contributes to the increase of the follicle cohort and of androgen levels, leading to follicular arrest and anovulation. In the male, AMH is synthesized at high levels by Sertoli cells from fetal life to puberty when serum AMH falls to levels similar to those observed in women. AMH is involved in the differentiation of the genital tract during fetal life and plays a role in Sertoli and Leydig cells differentiation and function. Serum AMH is used to assess Sertoli cell function in children with disorders of sex development and various conditions affecting the hypothalamic–pituitary–testicular axis. Although the reproductive function of male relative of women with PCOS has been poorly investigated, adolescents have elevated levels of AMH which could play a detrimental role on their fertility.

Impaired steroid hormone feedback in polycystic ovary syndrome: Evidence from preclinical models for abnormalities within central circuits controlling fertility

Polycystic ovary syndrome (PCOS) is the most common endocrinopathy and cause of infertility in women of reproductive age worldwide. Despite diagnostic features of anovulation, polycystic ovarian morphology, and high androgen secretion indicating the syndrome are the result of ovarian dysfunction, alterations to central neuroendocrine circuits that control reproductive capacity may drive PCOS symptoms. Resistance of gonadotrophin-releasing hormone (GnRH) neurons in the hypothalamus to inhibition by sex steroid hormone-negative feedback leads to a rapid frequency of pulsatile gonadotrophin secretion, which, in turn, drives the ovarian features of the disease. As GnRH neurons do not express steroid hormone receptors, impaired negative feedback is hypothesized to occur within an upstream network that controls GnRH pulse generation. This review will discuss the latest work from preclinical animal models of PCOS used to dissect the specific central mechanisms involved in impaired steroid hormone feedback. In particular, this review will focus on research that indicates neurons in the arcuate nucleus of the hypothalamus that express Kisspeptin, Neurokinin B and Dynorphin (KNDy cells) or γ-aminobutyric acid are targets of androgen-mediated impairment of steroid hormone feedback. Finally, this review will explore the development of therapeutic agents targeting neurons that control LH pulse frequency to resolve PCOS symptoms in the clinic.

Basal and dynamic relationships between serum anti-Müllerian hormone and gonadotropins in patients with functional hypothalamic amenorrhea, with or without polycystic ovarian morphology

BACKGROUND

To evaluate in women with functional hypothalamic amenorrhea (FHA), whether there is a difference between patients with and without polycystic ovarian morphology (PCOM) concerning the response to a gonadotropin releasing hormone (GnRH) stimulation test and to pulsatile GnRH treatment.

METHODS

In a retrospective observational study, 64 women with FHA who underwent a GnRH stimulation test and 32 age-matched controls without PCOM were included. Pulsatile GnRH treatment was provided to 31 FHA patients and three-month follow-up data were available for 19 of these.

RESULTS

Serum levels of gonadotropins and estradiol were lower in FHA women than in controls (p < 0.05). FHA patients revealed PCOM in 27/64 cases (42.2%). FHA patients without PCOM revealed lower anti-Müllerian hormone (AMH) levels than controls (median 2.03 ng/mL, IQR 1.40-2.50, versus 3.08 ng/mL, IQR 2.24-4.10, respectively, p < 0.001). Comparing FHA patients with and without PCOM, the latter revealed lower AMH levels, a lower median LH increase after the GnRH stimulation test (240.0%, IQR 186.4-370.0, versus 604.9%, IQR 360.0-1122.0; p < 0.001) as well as, contrary to patients with PCOM, a significant increase in AMH after three months of successful pulsatile GnRH treatment (median 1.69 ng/mL at baseline versus 2.02 ng/mL after three months of treatment; p = 0.002).

CONCLUSIONS

In women with FHA without PCOM, the phenomenon of low AMH levels seems to be based on relative gonadotropin deficiency rather than diminished ovarian reserve. AMH tended to rise after three months of pulsatile GnRH treatment. The differences found between patients with and without PCOM suggest the former the existence of some PCOS-specific systemic and/or intra-ovarian abnormalities.

Defining Reference Ranges for Serum Anti-Müllerian Hormone on a Large Cohort of Normozoospermic Adult Men Highlights New Potential Physiological Functions of AMH on FSH Secretion and Sperm Motility

BACKGROUND

Few studies to date have attempted to measure serum anti-Müllerian hormone (AMH) levels in adult men, and solid references ranges have not yet been defined in a large cohort.

OBJECTIVE

In this study, we aimed, first, to establish the reference ranges for serum AMH and AMH-to-total testosterone ratio (AMH/tT) in adult males. Second, we investigated the relationship between serum AMH and both reproductive hormones and semen parameters.

METHODS

This single-center retrospective study included 578 normozoospermic adult men. Serum AMH concentrations were determined with an automated sandwich chemiluminescent immunoassay.

RESULTS

The median serum AMH was 43.5 pmol/L. The 2.5th and 97.5th percentile values for serum AMH and AMH/tT were 16.4 and 90.3 pmol/L and 0.45 and 3.43, respectively. AMH was positively correlated with inhibin B and sperm concentration and negatively correlated with age, follicle-stimulating hormone (FSH), and progressive sperm motility. Interestingly, using immunofluorescence, we documented for the first time that AMH type II receptor (AMH-R2) is expressed in ejaculated human spermatozoa and gonadotrophic cells in the postmortem pituitary gland.

CONCLUSIONS

We establish a new age-specific reference range for serum AMH and AMH/tT. Moreover, AMH-R2 expression in human spermatozoa and gonadotrophic cells, together with the relationship between serum AMH levels and sperm motility or mean FSH levels, highlight new potential functions of AMH in regulating sperm motility or FSH secretion in adult men.

High androgen concentrations in follicular fluid of polycystic ovary syndrome women

BACKGROUND

According to current definitions of Polycystic Ovary Syndrome (PCOS), hyperandrogenism is considered as a key element in the pathogenesis of this common endocrinopathy. However, until now, studies about ovarian androgen profile in women are very rare. Our aim was then to characterise the expression profile of the androgens in follicular fluid of 30 PCOS patients, and compare it to those of 47 Control women and 29 women with only polycystic ovary morphology on ultrasounds (ECHO group).

METHODS

A retrospective, single-centre cohort study was performed. The intrafollicular concentrations of the key androgens were assessed and correlated with the intrafollicular levels of some adipokines of interest. Androgens were quantified by mass spectrophotometry combined with ultra-high-performance liquid chromatography, while adipokine concentrations were measured by ELISA assays.

RESULTS

In PCOS patients, the intrafollicular concentrations of the androgens synthesised by ovarian theca cells, i.e., 17OH-pregnenolone, dehydroepiandrosterone, Δ4-androstenedione and testosterone, were significantly higher than those of the androgens of adrenal origin, and positively correlated with the main PCOS clinical and biological features, as well as with the adipokines mostly expressed in the follicular fluid of PCOS patients, i.e. resistin, omentin, chemerin and apelin. Conversely, Control women showed the highest levels of 17OH-progesterone, deoxycorticosterone and 11-deoxycortisol. Confirming these results, apelin levels were negatively associated with pregnenolone and deoxycorticosterone concentrations, while visfatin levels, which were higher in the Control group, negatively correlated with the Δ4-androstenedione and testosterone ones.

CONCLUSIONS

PCOS is characterised by a selective increase in the intrafollicular levels of the androgens synthesised by theca cells, strengthening the hypothesis that ovarian hyperandrogenism plays a central role in its pathogenesis. Further, the significant correlation between the intrafollicular concentrations of the androgens and most of the adipokines of interest, including apelin, chemerin, resistin and omentin, confirms the existence of a close relationship between these two hormonal systems, which appear deeply involved in ovarian physiology and PCOS physiopathology.

The role of gonadotropin-releasing hormone neurons in polycystic ovary syndrome

Given the critical central role of gonadotropin-releasing hormone (GnRH) neurons in fertility, it is not surprising that the GnRH neural network is implicated in the pathology of polycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility. Although many symptoms of PCOS relate most proximately to ovarian dysfunction, the central reproductive neuroendocrine system ultimately drives ovarian function through its regulation of anterior pituitary gonadotropin release. The typical cyclical changes in frequency of GnRH release are often absent in women with PCOS, resulting in a persistent high-frequency drive promoting gonadotropin changes (i.e., relatively high luteinizing hormone and relatively low follicle-stimulating hormone concentrations) that contribute to ovarian hyperandrogenemia and ovulatory dysfunction. However, the specific mechanisms underpinning GnRH neuron dysfunction in PCOS remain unclear. Here, we summarize several preclinical and clinical studies that explore the causes of aberrant GnRH secretion in PCOS and the role of disordered GnRH secretion in PCOS pathophysiology.