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

Altered GnRH neuron-glia networks close to interface of polycystic ovary syndrome: Molecular mechanism and clinical perspectives

Polycystic ovary syndrome (PCOS) has been noticed as a neuroendocrine syndrome manifested by reproductive hormone dysregulation involving increased luteinizing hormone (LH) pulse frequency and an increased LH to follicle-stimulating hormone ratio, yet theory is just beginning to be established. Neuroglia located in the arcuate nucleus and median eminence (ARC-ME) that are close to gonadotropin-releasing hormone (GnRH) axon terminals, comprise the blood-brain barrier and fenestrated vessels implying their putative roles in the modulation of the abnormal GnRH pulse in PCOS. This review outlines the disturbances of neuron-glia networks that underlie hypothetically the deregulation of GnRH-LH release and impaired sex hormone negative feedback in PCOS. We then discuss chronic and low-grade inflammatory status together with gut dysbiosis and how the detriments may intrude the hypothalamus by virtue of violating interfaces between the brain and periphery, which might contribute to the etiology of the impaired neural circuits in the ARC-ME to induce PCOS.

Sexual response in women with polycystic ovary syndrome: a case-control study

OBJECTIVE

To study genital response and sexual arousal in women with and without polycystic ovary syndrome (PCOS) and assess associations with sex steroid levels.

DESIGN

This observational prospective case-control study was conducted from March 2017 until March 2020.

SETTING

University Hospital.

PATIENT(S)

Heterosexual women with (n = 68) and without (n = 67) PCOS, aged 18-40 years, in a steady relationship and without any comorbidities.

INTERVENTION(S)

All participants underwent an extensive medical and endocrine screening as well as assessment of genital blood flow (vaginal pulse amplitude), assessed with photoplethysmography), and sexual arousal and affect (Likert scale questionnaire) in response to erotic and vibrotactile stimulation.

MAIN OUTCOME MEASURE(S)

Vaginal pulse amplitude, lubrication, subjective sexual arousal, and affect.

RESULT(S)

There were no significant differences in genital blood flow response and self-reported lubrication between women with and without PCOS. After adjusting for confounders, women with PCOS did report significantly lower positive affect in the fantasy and vibrotactile condition than those without PCOS. Regression analyses adjusted for confounders showed only few and weak associations of sexual responses with androgen levels explaining only a maximum of 6% of variance in all models in women with and those without PCOS. The PCOS group showed only weak associations between subjective sexual arousal and dehydroepiandrosterone (fantasy, β = 1.719, adjusted R2 = 0.020) and sex hormone binding globulin (fantasy, β = -1.728, adjusted R2 = 0.044).

CONCLUSION(S)

Women with PCOS show similar genital sexual response and lubrication but lower positive affect than those without PCOS; however, only few and weak associations with the androgen levels were found. The androgen levels are not indicative of genital response and subjective arousal. Sexual function should be discussed in clinical care and psychosexual counseling should be offered.

CLINICAL TRIAL REGISTRATION NUMBER

CCMO register, NL55484.078.16.

A repeated gonadotropin-releasing hormone agonist trigger improves pregnancy outcomes of frozen-thawed embryo transfer in GnRH antagonist cycles: a retrospective propensity-matched score analysis

PURPOSE

To evaluate whether co-treatment of repeated GnRHa triggers with GnRH antagonist protocols can improve the clinical outcomes in in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET) procedures.

METHODS

In this retrospective study, 712 Chinese Han women aged 20-42 undergoing autologous IVF/ICSI-ET with a flexible GnRH antagonist protocol were analyzed. The 735 cycles were split into the single (n = 238) and the repeated (n = 497) GnRHa groups. In the single GnRHa group, 0.2 mg of triptorelin was given for oocyte maturation, whereas in the repeated GnRHa group, two doses of 0.2 mg were administered 12 h apart. PSM design was used for a fair comparison. The main study outcomes included the clinical pregnancy rate (CPR), live birth rate (LBR), good-quality embryo rate, and fertilization rate. Multivariate logistic regression analyses were used to identify all potential factors affecting clinical outcomes.

RESULTS

Post-PSM, analysis of 159 cycles per group showed the repeated GnRHa group outperforming the single GnRHa group in IVF fertilization rates (71.5% vs. 67.7%, P < 0.05) and good-quality embryo rate (47.1% vs. 43.7%, P < 0.05). Furthermore, the repeated GnRHa group achieved higher CPR (72.6% vs. 53.4%, P < 0.05) and LBR (59.7% vs. 43.8%, P < 0.05) in FET cycles. Multivariate logistic regression indicated a significant negative correlation between the use of a single GnRHa trigger and both clinical pregnancy (OR = 0.382, P < 0.05) and live birth (OR = 0.518, P < 0.05).

CONCLUSION

Our study reported that individuals who received a repeated GnRHa trigger exhibited higher CPR and LBR during FET cycles compared to those who received a single dose GnRHa trigger.

New insights into the relationship of antimüllerian hormone with polycystic ovary syndrome and its diagnostic accuracy: an updated and extended meta-analysis using a marginal beta-binomial model

OBJECTIVE

This study aimed to investigate the diagnostic role of antimüllerian hormone in polycystic ovary syndrome using an advanced marginal beta-binomial statistical model, and present the optimal cutoff by different age groups, geographical locations, body mass indexes, and other relevant factors.

DATA SOURCES

A comprehensive and systematic literature search was conducted in Web of Science, PubMed/Medline, Scopus, Cochrane Library, Embase, and ProQuest until August 2024.

STUDY ELIGIBILITY CRITERIA

Epidemiologic studies that used the Androgen Excess and Polycystic Ovary Syndrome Society, National Institutes of Health, or Rotterdam diagnostic criteria for polycystic ovary syndrome were included in this meta-analysis. Studies were eligible for inclusion if they provided information on the sensitivity and specificity of antimüllerian hormone or related data that allowed for the calculation of these parameters, and/or data on odds ratios and means.

METHODS

The diagnostic efficacy of antimüllerian hormone was assessed using the marginal beta-binomial statistical model and the summary receiver operating characteristic method in terms of pooled sensitivity, specificity, and diagnostic odds ratio with 95% confidence interval. Pooled weighted mean difference and pooled odds ratios with 95% confidence interval were estimated using a random effects model.

RESULTS

A total of 202 observational studies were included in the pooled analysis, of which 106 studies (including 19,465 cases and 29,318 controls) were used for meta-analysis of sensitivity/specificity and 186 studies (including 30,656 cases and 34,360 controls) for meta-analysis of mean difference. The pooled sensitivity, specificity, and diagnostic odds ratio for antimüllerian hormone were 0.79 (95% confidence interval, 0.52-0.97), 0.82 (95% confidence interval, 0.64-0.99), and 17.12 (95% confidence interval, 14.37-20.32), respectively. The area under the curve based on the summary receiver operating characteristic model was 0.90 (95% confidence interval, 0.87-0.93). Antimüllerian hormone levels were significantly higher in women with polycystic ovary syndrome than in control women (weighted mean difference, 4.91; 95% confidence interval, 4.57-5.27). In addition, individuals with higher antimüllerian hormone levels were more likely to be affected by polycystic ovary syndrome (odds ratio, 23.17; 95% confidence interval, 18.74-28.66; I2=94%; P<.001). A serum antimüllerian hormone concentration of >5.39 ng/mL was associated with polycystic ovary syndrome (sensitivity, 88.6%; specificity, 92.75%; likelihood ratio for a positive test result, 12.21; likelihood ratio for a negative test result, 0.12).

CONCLUSION

According to the results of this meta-analysis, serum antimüllerian hormone concentration is a valuable biomarker for the diagnosis of polycystic ovary syndrome. The cutoff points suggested by the current meta-analysis need to be evaluated and validated by future studies before their implementation into clinical practice.

Targeted inhibition of kisspeptin neurons reverses hyperandrogenemia and abnormal hyperactive LH secretion in a preclinical mouse model of polycystic ovary syndrome

STUDY QUESTION

Do hyperactive kisspeptin neurons contribute to abnormally high LH secretion and downstream hyperandrogenemia in polycystic ovary syndrome (PCOS)-like conditions and can inhibition of kisspeptin neurons rescue such endocrine impairments?

SUMMARY ANSWER

Targeted inhibition of endogenous kisspeptin neuron activity in a mouse model of PCOS reduced the abnormally hyperactive LH pulse secretion and hyperandrogenemia to healthy control levels.

WHAT IS KNOWN ALREADY

PCOS is a reproductive disorder characterized by hyperandrogenemia, anovulation, and/or polycystic ovaries, along with a hallmark feature of abnormal LH hyper-pulsatility, but the mechanisms underlying the endocrine impairments remain unclear. A chronic letrozole (LET; aromatase inhibitor) mouse model recapitulates PCOS phenotypes, including polycystic ovaries, anovulation, high testosterone, and hyperactive LH pulses. LET PCOS-like females also have increased hypothalamic kisspeptin neuronal activation which may drive their hyperactive LH secretion and hyperandrogenemia, but this has not been tested.

STUDY DESIGN, SIZE, DURATION

Transgenic KissCRE+/hM4Di female mice or littermates Cre- controls were treated with placebo, or chronic LET (50 µg/day) to induce a PCOS-like phenotype, followed by acute (once) or chronic (2 weeks) clozapine-N-oxide (CNO) exposure to chemogenetically inhibit kisspeptin cells (n = 6 to 10 mice/group).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Key endocrine measures, including in vivo LH pulse secretion patterns and circulating testosterone levels, were assessed before and after selective kisspeptin neuron inhibition and compared between PCOS groups and healthy controls. Alterations in body weights were measured and pituitary and ovarian gene expression was determined by qRT-PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

Acute targeted inhibition of kisspeptin neurons in PCOS mice successfully lowered the abnormally hyperactive LH pulse secretion (P < 0.05). Likewise, chronic selective suppression of kisspeptin neuron activity reversed the previously high LH and testosterone levels (P < 0.05) down to healthy control levels and rescued reproductive gene expression (P < 0. 05).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Ovarian morphology was not assessed in this study. Additionally, mouse models can offer mechanistic insights into neuroendocrine processes in PCOS-like conditions but may not perfectly mirror PCOS in women.

WIDER IMPLICATIONS OF THE FINDINGS

These data support the hypothesis that overactive kisspeptin neurons can drive neuroendocrine PCOS-like impairments, and this may occur in PCOS women. Our findings complement recent clinical investigations using NKB receptor antagonists to lower LH in PCOS women and suggest that pharmacological dose-dependent modulation of kisspeptin neuron activity may be a valuable future therapeutic target to clinically treat hyperandrogenism and lower elevated LH in PCOS women.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by NIH grants R01 HD111650, R01 HD090161, R01 HD100580, P50 HD012303, R01 AG078185, and NIH R24 HD102061, and a pilot project award from the British Society for Neuroendocrinology. There are no competing interests.

Are Women with Polycystic Ovary Syndrome at Increased Risk of Alzheimer Disease? Lessons from Insulin Resistance, Tryptophan and Gonadotropin Disturbances and Their Link with Amyloid-Beta Aggregation

Alzheimer disease, the leading cause of dementia, and polycystic ovary syndrome, one of the most prevalent female endocrine disorders, appear to be unrelated conditions. However, studies show that both disease entities have common risk factors, and the amount of certain protein marker of neurodegeneration is increased in PCOS. Reports on the pathomechanism of both diseases point to the possibility of common denominators linking them. Dysregulation of the kynurenine pathway, insulin resistance, and impairment of the hypothalamic-pituitary-gonadal axis, which are correlated with amyloid-beta aggregation are these common areas. This article discusses the relationship between Alzheimer disease and polycystic ovary syndrome, with a particular focus on the role of disorders of tryptophan metabolism in both conditions. Based on a review of the available literature, we concluded that systemic changes occurring in PCOS influence the increased risk of neurodegeneration.

Psychological symptoms and brain activity alterations in women with PCOS and their relation to the reduced quality of life: a narrative review

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common feminine endocrine disorder, characterized by androgen excess, ovulatory dysfunction, and polycystic ovarian morphology. The negative impact of symptoms on the quality of life (QoL) of patients is still not clear.

PURPOSE

The present review aimed at studying the impact of the symptoms, the psychological symptoms, and brain alterations in women with PCOS.

METHODS

A systematic search was undertaken for studies that assessed the impact of PCOS symptoms on QoL, psychological symptoms, and brain alterations in PCOS patients.

RESULTS

Most of the information about QoL came from psychometric studies, which used culture-based questionnaires. Alterations of sleep quality, body image, and mood disorders can negatively affect the QoL of the patients. Sexual satisfaction and desire were affected by PCOS. Brain imaging studies showed functional alterations that are associated with impairments of visuospatial working memory, episodic and verbal memory, attention, and executive function.

CONCLUSIONS

Several factors can negatively influence the quality of life of the patients, and they are directly related to hyperandrogenism and the risk of infertility. In particular, obesity, hirsutism, acne, and the fear of infertility can have a direct impact on self-esteem and sexual function. Metabolic and psychiatric comorbidities, such as mood, anxiety, and eating disorders, can affect the well-being of the patients. Moreover, specific cognitive alterations, such as impairments in attention and memory, can limit PCOS patients in a series of aspects of daily life.

Therapeutic potential of endometrial stem cells encapsulated in alginate/gelatin hydrogel to treat of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder in women, often leading to infertility due to anovulation. Recent advances suggest that endometrial stem cells (EnSCs) hold considerable promise for tissue regeneration, which could be pivotal in treating PCOS. To enhance the survival and stabilization of EnSCs within the ovary, the EnSCs were encapsulated in an injectable alginate/gelatin hydrogel (SC-H), which has excellent biocompatibility to support the survival of EnSCs. Polycystic ovary syndrome was induced in female Wistar rats using intraperitoneal injection of letrozole over 21 days. Then the rats were treated with SC, SC-H and clomiphene citrate for one-month post-PCOS induction. The effects of these treatments were evaluated based on changes in body and ovarian weights, inflammatory markers, endocrine profiles, and ovarian histology. The Induction of PCOS led to a significant increase in body and ovarian cyst weight, elevated serum levels of testosterone, luteinizing hormone (LH), and anti-Müllerian hormone (AMH), alongside reduced follicle-stimulating hormone (FSH) and progesterone levels. Histologically, there was a decrease in granulosa cells, immature follicles, and corpus luteum numbers. Treatment with SC and SC-H significantly mitigated these alterations, indicating improved PCOS conditions. Our findings demonstrate that SC and SC-H treatments can effectively ameliorate the symptoms of letrozole-induced PCOS in rats, primarily through their anti-inflammatory effects. This study lays the groundwork for potential clinical applications of EnSCs encapsulated in alginate/gelatin hydrogel as a novel therapeutic strategy for PCOS, highlighting the importance of biomaterials in stem cell-based therapies.

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.

Polycystic ovary syndrome

Despite affecting ~11-13% of women globally, polycystic ovary syndrome (PCOS) is a substantially understudied condition. PCOS, possibly extending to men's health, imposes a considerable health and economic burden worldwide. Diagnosis in adults follows the International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome, requiring two out of three criteria - clinical or biochemical hyperandrogenism, ovulatory dysfunction, and/or specific ovarian morphological characteristics or elevated anti-Müllerian hormone. However, diagnosing adolescents omits ovarian morphology and anti-Müllerian hormone considerations. PCOS, marked by insulin resistance and hyperandrogenism, strongly contributes to early-onset type 2 diabetes, with increased odds for cardiovascular diseases. Reproduction-related implications include irregular menstrual cycles, anovulatory infertility, heightened risks of pregnancy complications and endometrial cancer. Beyond physiological manifestations, PCOS is associated with anxiety, depression, eating disorders, psychosexual dysfunction and negative body image, collectively contributing to diminished health-related quality of life in patients. Despite its high prevalence persisting into menopause, diagnosing PCOS often involves extended timelines and multiple health-care visits. Treatment remains ad hoc owing to limited understanding of underlying mechanisms, highlighting the need for research delineating the aetiology and pathophysiology of the syndrome. Identifying factors contributing to PCOS will pave the way for personalized medicine approaches. Additionally, exploring novel biomarkers, refining diagnostic criteria and advancing treatment modalities will be crucial in enhancing the precision and efficacy of interventions that will positively impact the lives of patients.

Assessing the clinical diagnostic value of anti-Müllerian hormone in polycystic ovarian syndrome and its correlation with clinical and metabolism indicators

BACKGROUND

This study investigated the association between Anti-Müllerian Hormone (AMH) and relevant metabolic parameters and assessed its predictive value in the clinical diagnosis of polycystic ovarian syndrome (PCOS).

METHODS

A total of 421 women aged 20-37 years were allocated to the PCOS (n = 168) and control (n = 253) groups, and their metabolic and hormonal parameters were compared. Spearman correlation analysis was conducted to investigate associations, binary logistic regression was used to determine PCOS risk factors, and receiver operating characteristic (ROC) curves were generated to evaluate the predictive value of AMH in diagnosing PCOS.

RESULTS

The PCOS group demonstrated significantly higher blood lipid, luteinizing hormone (LH), and AMH levels than the control group. Glucose and lipid metabolism and hormonal disorders in the PCOS group were more significant than in the control group among individuals with and without obesity. LH, TSTO, and AMH were identified as independent risk factors for PCOS. AMH along with LH, and antral follicle count demonstrated a high predictive value for diagnosing PCOS.

CONCLUSION

AMH exhibited robust diagnostic use for identifying PCOS and could be considered a marker for screening PCOS to improve PCOS diagnostic accuracy. Attention should be paid to the effect of glucose and lipid metabolism on the hormonal and related parameters of PCOS populations.

Association of Serum Anti-Mullerian Hormone and Free Testosterone with Different Phenotypes of Polycystic Ovary Syndrome

Background

Anti-Müllerian hormone (AMH) has lately been connected to polycystic ovary syndrome (PCOS) in a growing body of research, even though hyperandrogenism is one of the primary symptoms of PCOS.Evaluate the association of serum anti-Müllerian hormone and free testosterone with different phenotypes of polycystic ovary syndrome.

Methods

This is cross-sectional study was carried out at Department of Biochemistry, College of Medicine, University of Baghdad, during the period from November 2023 to March 2024. It included 111 women, 91 of these women, age range (18-40 year) were diagnosed with polycystic ovary syndrome according to 2003 Rotterdam Consensus criteria, and 20 women were apparently healthy women. The PCOS women were sub-grouped into four phenotype groups (A, B, C and D). Investigations included serum measurements of free testosterone and anti-müllerian hormone by using enzyme linked immunosorbent assay (ELISA) technique in all included women.

Results

The results revealed that phenotype A is the predominant one of PCOS, while the B phenotype is the rare one. The mean (±SEM) values of free testosterone levels of phenotypes A, B, and C were significantly higher those of phenotype D and controls (p=0.001). The mean (±SEM) value of serum anti-Mullerian hormone levels was significantly increased in phenotypes A (p=0.04) and D (p=0.01) than C phenotype.

Conclusions

Phenotype A is the predominant one of PCOS phenotypes and is associated with highest serum AMH, free testosterone and obesity. Both free testosterone and AMH are helpful in differentiation of different phenotypes of PCOS.

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.

Androgen excess: a hallmark of polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a metabolic, reproductive, and psychological disorder affecting 6-20% of reproductive women worldwide. However, there is still no cure for PCOS, and current treatments primarily alleviate its symptoms due to a poor understanding of its etiology. Compelling evidence suggests that hyperandrogenism is not just a primary feature of PCOS. Instead, it may be a causative factor for this condition. Thus, figuring out the mechanisms of androgen synthesis, conversion, and metabolism is relatively important. Traditionally, studies of androgen excess have largely focused on classical androgen, but in recent years, adrenal-derived 11-oxygenated androgen has also garnered interest. Herein, this Review aims to investigate the origins of androgen excess, androgen synthesis, how androgen receptor (AR) signaling mediates adverse PCOS traits, and the role of 11-oxygenated androgen in the pathophysiology of PCOS. In addition, it provides therapeutic strategies targeting hyperandrogenism in PCOS.

[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.

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).