Kisspeptin and LH pulsatile temporal coupling in PCOS patients

Jiawei Buzhong Yiqi Decoction attenuates polycystic ovary syndrome through regulating kisspeptin-GPR54-AKT-SHBG system

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine disorders. Accumulated evidence has suggested the indispensable role of kisspeptin-G protein-coupled receptor (GPR54) system and SHBG in development of PCOS. However, potential mechanisms and their relationship are unclear. Jiawei Buzhong Yiqi Decoction (JWBZYQ) has been reported to ameliorate obese PCOS. Whereas, potential mechanisms remain elusive.

PURPOSE

To determine whether JWBZYQ attenuates PCOS by regulating the kisspeptin-GPR54 system and SHBG production. And to explore potential mechanisms.

METHODS

An overweight PCOS rat model was developed with testosterone propionate (TP) and high-fat diet (HFD). The efficacy of JWBZYQ was assessed by tracking changes in weight, estrous cycle, ovarian morphology, and serum sex hormone levels. Additionally, kisspeptin-GPR54 system expression in multiple organs and PI3K-AKT pathway activity in liver of different rats were detected. Modifications in SHBG production were also measured. Kisspeptin54 was administered to establish a cellular model. The levels of AKT phosphorylation and SHBG protein within HepG2 cells were analyzed. Finally, confirmatory studies were performed using AKT phosphorylation activator and inhibitor.

RESULTS

JWBZYQ effectively attenuated the overweight, disrupted estrous cycle, altered sex hormone levels, and aberrant ovarian morphology in PCOS rats. Meanwhile, PCOS rats exhibited elevated levels of kisspeptin and GPR54, along with reduced SHBG levels, which could be reversed by JWBZYQ. These alterations might be connected with the activation of AKT phosphorylation. In vitro experiment identified that JWBZYQ could rectify the hyperactivated AKT phosphorylation and deficient production of SHBG caused by kisspeptin54.

CONCLUSIONS

Overexpressed kisspeptin-GPR54 system inhibited SHBG synthesis in PCOS. JWBZYQ curtailed the exorbitant expression of kisspeptin and GPR54, which moderated the rise in AKT phosphorylation and subsequently promoted the production of SHBG.

Kisspeptin expression during menstruation in PCOS patients undergoing ovulation induction and the correlation with early pregnancy

PURPOSE

To examine the pattern of kisspeptin expression throughout the menstrual cycle in polycystic ovary syndrome (PCOS) patients under the ovulation induction and identify any possible associations with early pregnancy.

MATERIALS AND METHODS

A prospective cohort of 80 PCOS women who expressed the desire for fertility was enrolled in this study. All of them received the ovulation induction by using letrozole. Levels of kisspeptin, luteinizing hormone (LH), and estradiol (E2) were measured at three different time points during menstruation. The early pregnancy rate was recorded for the study participants after three ovulation cycles.

RESULTS

Kisspeptin levels varied regularly during the menstrual cycle, reaching a peak on the day of hCG injection and decreasing after ovulation. There was no significant correlation between kisspeptin and LH levels. Basal kisspeptin levels decreased after letrozole treatment without a significant difference while LH and E2 levels decreased significantly. PCOS participants who became pregnant early had higher basal kisspeptin levels compared to non-pregnant PCOS patients, which had a significant difference (P = 0.006). And the average basal kisspeptin level in pregnant patients was 2293.0 ± 398.7 pg/ml, with a 95% confidence interval of 1511.5-3074.5 pg/ml.

CONCLUSION

Kisspeptin levels in PCOS women undergoing ovulation induction showed a regular variation, which was similar with the healthy women reported in previous studies. The use of LE may result in PCOS endocrine improvement and fertility achievement. In a certain range, kisspeptin might be a potential predictor for early pregnancy in PCOS patients as people with slightly higher basal kisspeptin levels seemed more likely to be pregnant.

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 role of the autonomic nervous system in polycystic ovary syndrome

This article reviewed the relationship between the autonomic nervous system and the development of polycystic ovary syndrome (PCOS). PCOS is the most common reproductive endocrine disorder among women of reproductive age. Its primary characteristics include persistent anovulation, hyperandrogenism, and polycystic ovarian morphology, often accompanied by disturbances in glucose and lipid metabolism. The body's functions are regulated by the autonomic nervous system, which consists mainly of the sympathetic and parasympathetic nervous systems. The autonomic nervous system helps maintain homeostasis in the body. Research indicates that ovarian function in mammals is under autonomic neural control. The ovaries receive central nervous system information through the ovarian plexus nerves and the superior ovarian nerves. Neurotransmitters mediate neural function, with acetylcholine and norepinephrine being the predominant autonomic neurotransmitters. They influence the secretion of ovarian steroids and follicular development. In animal experiments, estrogen, androgens, and stress-induced rat models have been used to explore the relationship between PCOS and the autonomic nervous system. Results have shown that the activation of the autonomic nervous system contributes to the development of PCOS in rat. In clinical practice, assessments of autonomic nervous system function in PCOS patients have been gradually employed. These assessments include heart rate variability testing, measurement of muscle sympathetic nerve activity, skin sympathetic response testing, and post-exercise heart rate recovery evaluation. PCOS patients exhibit autonomic nervous system dysfunction, characterized by increased sympathetic nervous system activity and decreased vagal nerve activity. Abnormal metabolic indicators in PCOS women can also impact autonomic nervous system activity. Clinical studies have shown that various effective methods for managing PCOS regulate patients' autonomic nervous system activity during the treatment process. This suggests that improving autonomic nervous system activity may be an effective approach in treating PCOS.

The Emerging Therapeutic Potential of Kisspeptin and Neurokinin B

Kisspeptin (KP) and neurokinin B (NKB) are neuropeptides that govern the reproductive endocrine axis through regulating hypothalamic gonadotropin-releasing hormone (GnRH) neuronal activity and pulsatile GnRH secretion. Their critical role in reproductive health was first identified after inactivating variants in genes encoding for KP or NKB signaling were shown to result in congenital hypogonadotropic hypogonadism and a failure of pubertal development. Over the past 2 decades since their discovery, a wealth of evidence from both basic and translational research has laid the foundation for potential therapeutic applications. Beyond KP's function in the hypothalamus, it is also expressed in the placenta, liver, pancreas, adipose tissue, bone, and limbic regions, giving rise to several avenues of research for use in the diagnosis and treatment of pregnancy, metabolic, liver, bone, and behavioral disorders. The role played by NKB in stimulating the hypothalamic thermoregulatory center to mediate menopausal hot flashes has led to the development of medications that antagonize its action as a novel nonsteroidal therapeutic agent for this indication. Furthermore, the ability of NKB antagonism to partially suppress (but not abolish) the reproductive endocrine axis has supported its potential use for the treatment of various reproductive disorders including polycystic ovary syndrome, uterine fibroids, and endometriosis. This review will provide a comprehensive up-to-date overview of the preclinical and clinical data that have paved the way for the development of diagnostic and therapeutic applications of KP and NKB.

Clinical management of androgen excess and defect in women

INTRODUCTION

Hyperandrogenism and hypoandrogenism are complex disorders involving multiple-organ systems. While androgen excess is a well-characterized condition, androgen deficiency still needs diagnostic criteria, as there are no specific cutoffs.

AREAS COVERED

We highlight the most recent findings on the role of androgens in female pathophysiology, investigating clinically relevant conditions of androgen insufficiency or excess throughout a woman's life, and their possible therapeutic management.

EXPERT OPINION

Combined oral contraceptives (COCs) should be considered as first-line therapy for the management of menstrual irregularity and/or clinical hyperandrogenism in adolescents with a clear diagnosis of polycystic ovary syndrome (PCOS). There are limited evidence-based data regarding specific types or doses of COCs for management of PCOS in women; however, the lowest effective estrogen dose should be considered for treatment. Despite evidence regarding safety, efficacy, and clinical use, testosterone therapy has not been approved for women by most regulatory agencies for treatment of hypoactive sexual desire disorder (HSDD). The long-term safety for treatments with testosterone is still to be evaluated, and this review highlights the need for more research in this area.

The efficacy of Linum usitatissimum seeds to inhibit estrogen receptor as a natural therapy for PCOS: An in silico and in vitro analysis

Polycystic ovarian syndrome (PCOS) is an endocrinological disorder aroused due to hormonal disturbances. It is characterized by anovulation due to an excess of androgen and estrogen hormones, thus leading to the formation of multiple cysts, imposing life-threatening conditions. This manuscript aimed to introduce a natural estrogen receptor (ESR) inhibitors that can provide protection against PCOS. The computational analysis of Linum usitatissimum seeds  compounds against ESR alpha receptor was performed, and the binding affinities of the ligand compounds and receptor proteins were scrutinized. Nine lignin compounds were docked, and the results were compared with that of reference estrogen receptor inhibitors, clomiphene, and tamoxifen. The binding affinity scores for pinoresinol, lariciresinol, secoisolariciresinol, and matairesinol were -10.67, -10.66, -10.91, and -10.60 kcal mol-1 , respectively. These were comparable to the binding affinity score of reference compounds -11.406 kcal mol-1 for clomiphene and -10.666 kcal mol-1 for tamoxifen. Prime MM-GBSA studies showcased that Linum usitatissimum seeds compounds exhibit significant efficacy and efficiency towards receptor protein. Moreover, MD-simulation studies were performed and the results depict that the lignin compounds form stable complexes at 300 K throughout the simulation time. For further clarity, in-vitro experiments were carried out. The results exhibit the decline in cell proliferation in a concentration-dependent manner by extract 1 (ethyl acetate) EX1 and extract 2 (petroleum ether) EX2. Hence, providing evidence regarding the anti-estrogenic activity of the sample extracts. Collectively, these results showed that flax seed can reduce the levels of estrogen, which can induce ovulation and prevent cyst formation, and ultimately can provide protection against PCOS.

Neuroendocrine, neurotransmitter, and gut microbiota imbalance contributing to potential psychiatric disorder prevalence in polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women, affecting up to 15% of reproductive-aged women. Polycystic ovarian syndrome is a heterogeneous disorder, both in the sense that many different factors may play a role in its manifestation and that multiple systems throughout the body can be affected. Polycystic ovarian syndrome has been linked to an increased prevalence of various psychiatric disorders, including depression and anxiety. Despite the socioeconomic effect that these disorders may have on patients with PCOS and society as a whole, this association is largely lacking in research. There are currently several theories regarding the link between PCOS and mental health. Some suggest that the overactive hypothalamic-pituitary-ovarian and hypothalamic-pituitary-adrenal axes in PCOS patients may alter the hormonal profile and contribute to the development of psychiatric disorders. Other studies speculate that abnormal levels of neurotransmitters and neuronal signaling may play a role. Recently, more research has begun to focus on the gut-brain axis, addressing the nutritional needs of PCOS patients. Studies show that dietary factors such as probiotics and micronutrient supplementation may significantly improve psychiatric symptoms in PCOS patients while helping regulate neurotransmitter levels in the body. In this review, we examine different theories regarding the association between PCOS and psychiatric disorders and point out different areas of research that are needed to broaden our understanding of this association.

Regulatory Effects of the Kiss1 Gene in the Testis on Puberty and Reproduction in Hezuo and Landrance Boars

Kisspeptin, a neuropeptide encoded by the Kiss1 gene, combines with its receptor Kiss1R to regulate the onset of puberty and male fertility by the hypothalamic-pituitary-gonadal axis. However, little is known regarding the expression signatures and molecular functions of Kiss1 in the testis. H&E staining revealed that well-arranged spermatogonia, spermatocytes, round and elongated spermatids, and spermatozoa, were observed in 4-, 6-, and 8-month-old testes compared to 1- and 3-month-old testes of Hezuo pigs; however, these were not observed in Landrance until 6 months. The diameter, perimeter, and cross-sectional area of seminiferous tubules and the perimeter and area of the tubular lumen increased gradually with age in both pigs. Still, Hezuo pigs grew faster than Landrance. The cloning results suggested that the Hezuo pigs' Kiss1 CDS region is 417 bp in length, encodes 138 amino acids, and is highly conserved in the kisspeptin-10 region. qRT-PCR and Western blot indicated that the expression trends of Kiss1 mRNA and protein were essentially identical, with higher expression levels at post-pubertal stages. Immunohistochemistry demonstrated that the Kiss1 protein was mainly located in Leydig cells and post-pubertal spermatogenic cells, ranging from round spermatids to spermatozoa. These studies suggest that Kiss1 is an essential regulator in the onset of puberty and spermatogenesis of boars.

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.

Neural substrates underlying rhythmic coupling of female reproductive and thermoregulatory circuits

Coordinated fluctuations in female reproductive physiology and thermoregulatory output have been reported for over a century. These changes occur rhythmically at the hourly (ultradian), daily (circadian), and multi-day (ovulatory) timescales, are critical for reproductive function, and have led to the use of temperature patterns as a proxy for female reproductive state. The mechanisms underlying coupling between reproductive and thermoregulatory systems are not fully established, hindering the expansion of inferences that body temperature can provide about female reproductive status. At present, numerous digital tools rely on temperature to infer the timing of ovulation and additional applications (e.g., monitoring ovulatory irregularities and progression of puberty, pregnancy, and menopause are developed based on the assumption that reproductive-thermoregulatory coupling occurs across timescales and life stages. However, without clear understanding of the mechanisms and degree of coupling among the neural substrates regulating temperature and the reproductive axis, whether such approaches will bear fruit in particular domains is uncertain. In this overview, we present evidence supporting broad coupling among the central circuits governing reproduction, thermoregulation, and broader systemic physiology, focusing on timing at ultradian frequencies. Future work characterizing the dynamics of reproductive-thermoregulatory coupling across the lifespan, and of conditions that may decouple these circuits (e.g., circadian disruption, metabolic disease) and compromise female reproductive health, will aid in the development of strategies for early detection of reproductive irregularities and monitoring the efficacy of fertility treatments.

Polycystic Ovary Syndrome as Metabolic Disease: New Insights on Insulin Resistance

Polycystic ovary syndrome (PCOS) is a very frequent disease that affects reproductive ability and menstrual regularity. Other than the criteria established at the Rotterdam consensus, in these last few years a new issue, insulin resistance, has been found frequently, and at a very high grade, in patients with PCOS. Insulin resistance occurs for several factors, such as overweight and obesity, but it is now clear that it occurs in patients with PCOS with normal weight, thus supporting the hypothesis that insulin resistance is independent of body weight. Evidence shows that a complex pathophysiological situation occurs that impairs post-receptor insulin signalling, especially in patients with PCOS and familial diabetes. In addition, patients with PCOS have a high incidence of non-alcoholic fatty liver disease related to the hyperinsulinaemia. This narrative review focuses on the recent new insights about insulin resistance in patients with PCOS, to better understand the metabolic impairment accounting for most of the clinical signs/symptoms of PCOS.

Gonadotropins as pharmacological agents in assisted reproductive technology and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex endocrinopathy associated with subfertility/infertility and pregnancy complications. Most PCOS women opt for assisted reproductive technologies (ART) for successful conception; however, optimization of the relative doses of the gonadotropins [follicle-stimulating hormone (FSH), luteinizing hormone (LH)/human chorionic gonadotropin (hCG)] for appropriate steroidogenesis, without causing ovarian hyperstimulatory syndrome (OHSS), is challenging. Embryonic factors probably do not contribute to pregnancy loss in PCOS women, albeit hormonal imbalance impairs the metabolic microenvironment critical for oocyte maturation and endometrial receptivity. Certain clinical studies have confirmed the role of metabolic corrections in increasing the rate of pregnancy in PCOS women. This review focuses on the impact of untimely high LHCGR and/or LH levels on oocyte/embryo quality, pregnancy outcomes in ART, and exploring LHCGR as a potential drug target in PCOS women.

Effects of electroacupuncture on the kisspeptin-gonadotropin-releasing hormone (GnRH) /luteinizing hormone (LH) neural circuit abnormalities and androgen receptor expression of kisspeptin/neurokinin B/dynorphin neurons in PCOS rats

BACKGROUND

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, anovulation, and polycystic ovaries. Electroacupuncture (EA) can effectively improve hyperandrogenism and increase ovulation frequency in patients with PCOS. Pieces of suggest that androgen activity in the brain is associated with impaired steroid negative feedback in such patients. Studies have shown that EA regulated androgen receptor (AR) expression and local factor levels (such as anti-Müllerian hormone and inhibin B) in the ovary of PCOS rats. However, few studies have explored the effect of EA on androgen activity in the brain.

OBJECTIVE

This study investigated the effect of EA on the kisspeptin-gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) neural circuit and sex hormone receptor expression in the hypothalamus of PCOS rats.

METHODS

PCOS signs were induced by letrozole administration, and the induced rats were treated with low-frequency EA at Guan Yuan acupoint (CV4). The effect of EA on PCOS-like signs was evaluated by observing changes in the body weight, ovarian quality, ovarian morphology, and serum sex hormone levels in rats. To explore the mechanism of the effect of EA on PCOS-like signs, the neuropeptide content of the kisspeptin-GnRH/LH neural circuit was assessed using enzyme-linked immunosorbent assay(ELISA); AR and estrogen receptor α (ERα) coexpression on kisspeptin/neurokinin B/dynorphin (KNDy) neurons was determined via triple-label immunofluorescence; and protein and mRNA expression of Kiss1, Ar, Esr1, and kisspeptin receptor (Kiss1r) was evaluated via western blotting and Reverse Transcription-Polymerase Chain Reaction (RT-PCR).

RESULTS

The results revealed that the estrous cycle of rats in the EA treatment group recovered, and their body and ovary weight reduced; ovarian morphology improved; serum testosterone and LH levels significantly decreased; and kisspeptin, GnRH, and dynorphin levels in hypothalamic arcuate nucleus significantly decreased. Compared with controls, the number of AR/Kiss1-positive cells increased, number of ERα/Kiss1-positive cells decreased, and protein and mRNA expression of Kiss1, Ar, and Kiss1r significantly increased in PCOS rats. However, EA treatment reversed these changes and reduced the expression of Kiss1, Ar, and Kiss1r significantly.

CONCLUSION

Improvement in the reproductive hallmarks of PCOS rats via EA may be achieved by regulating the kisspeptin-GnRH/LH circuit via androgen activity attenuation. Thus, the results provide an experimental basis for acupuncture as an adjuvant medical therapy on PCOS.

Virgin coconut oil reverses behavioral phenotypes of letrozole-model of PCOS in Wistar rats via modulation of NRF2 upregulation

Objectives

Polycystic ovarian syndrome (PCOS) is an endocrine disorder associated with insulin resistance, hyperandrogenism, and sub-infertility. Virgin coconut oil (VCO) has been reported to have health benefits, such as anti-inflammatory, anti-oxidant, and antiviral properties. This study investigated the effects of dietary VCO supplementation on memory and cognitive impairment in female rats with letrozole induced PCOS.

Methods

Thirty female rats were randomly divided into five groups. All rats except controls were treated with letrozole for 21 days to induce PCOS and were subsequently treated for 14 days with 10% VCO, clomiphene (CLO), or VCO + CLO. Three neurobehavioral tests were conducted: elevated plus maze, Y maze, and novel object recognition tests.

Results

Our results indicated statistically elevated serum concentrations of sex hormones in rats with PCOS, compared with the control and treated groups. In addition, all treated groups showed significant reversal of the low serum concentrations of catalase and down-regulated gene expression of Nrf2 in the hippocampus seen in the PCOS rats. In addition, gene expression of acetylcholine esterase was up-regulated in PCOS rats, and was statistically reverted in the VCO treated groups.

Conclusion

Anxiety-like behavior and impaired short-term memory were observed in PCOS rats; however, VCO supplementation reversed these effects by modulating the gene expression of Nrf2 and AchE.

A brief insight into the etiology, genetics, and immunology of polycystic ovarian syndrome (PCOS)

Polycystic ovarian syndrome (PCOS) is a prevailing endocrine and metabolic disorder occurring in about 6-20% of females in reproductive age. Most symptoms of PCOS arise early during puberty. Since PCOS involves a combination of signs and symptoms, thus it is considered as a heterogeneous disorderliness. The most accepted diagnostic criteria is Rotterdam criteria which involves two of the latter three features: (a) hyperandrogenism, (b) oligo- or an-ovulation, and (c) polycystic ovaries. The persistent hormonal imbalance leads to multiple small antral follicles formation and irregular menstrual cycle, ultimately causing infertility among females. Insulin resistance, cardiovascular diseases, abdominal obesity, psychological disorders, infertility, and cancer are also related to PCOS. These pathophysiologies associated with PCOS are interrelated with each other. Hyperandrogenism causes insulin resistance and hyperglycemia, leading to ROS formation, oxidative stress, and abdominal adiposity. In consequence, inflammation, ROS production, insulin resistance, and hyperandrogenemia also increase. Elevation of AGEs in the body either produced endogenously or consumed from diet exaggerates PCOS symptoms and is also related to ovarian dysfunction. This review summarizes how AGE formation, inflammation, and oxidative stress are significantly essential in PCOS progression. Alterations during prenatal development like exposure to excess AMH, androgens, or toxins (bisphenol-A, endocrine disruptors, etc.) may also be the etiologic mechanism behind PCOS. Although the etiology of this disorder is unclear, environmental and genetic factors are primarily involved. Physical inactivity, as well as unhealthy eating habits, has a vital role in the progression of PCOS. This review outlines a collection of specific genes phenotypically linked with PCOS. Furthermore, beneficial effect of metformin in maintaining endocrine abnormalities and ovarian function is also mentioned. Kisspeptin is a protein which helps in onset of puberty and increases GnRH pulsatile release during ovulation as well as role of KNDy neurons in GnRH pulsatile signal required for reproduction are also elaborated. This review also focuses on the immunology related to PCOS involving chronic low-grade inflammation, and how the alterations within the follicular microenvironment are intricated in the development of infertility in PCOS patients. How PCOS develops following antiepileptic and psychiatric medication is also expanded in this review. Initiation of antiandrogen treatment in early age (≤ 25 years) might be helpful in spontaneous conception in PCOS women. The role of BMP (bone morphogenetic proteins) in folliculogenesis and their expression in oocytes and granulosa cells are also explained. GDF8 and SERPINE1 expression in PCOS is given in detail.

Key signalling pathways underlying the aetiology of polycystic ovary syndrome

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

Associations of the KiSS-1 and GPR54 genetic polymorphism with polycystic ovary syndrome in Yunnan, China

BSCKGROUND

Polycystic ovary syndrome (PCOS) is a heterogeneous condition that increases the risk for serious health complications among women. Thus, in this study, we aimed to identify polymorphisms in the KiSS-1 and GPR54 genes and investigate the associations between KiSS-1, BMI, FSH, LH, and estradiol in Chinese women with PCOS.

METHODS

This study recruited women with PCOS (n = 60) and controls (n = 60). We collected blood samples and measured endocrine indicators (kisspeptin, FSH, LH-FSH ratio, estradiol, prolactin, and testosterone). PCR and Snapshots were performed to screen single nucleotide polymorphisms (SNPs) of the KiSS-1 and GPR54 genes.

RESULTS

Compared with the controls, endocrine and metabolic disturbances in women with PCOS were reflected in significantly higher levels of BMI, LH, LH-FSH ratio, prolactin, and testosterone. Serum kisspeptin levels were significantly higher and positively correlated with LH and T levels (p < 0.05). No identified SNPs of KiSS-1 and GPR54 showed significant differences in frequency between patients and controls. The mutant G allele was highly predisposed to polymorphism in the PCOS GPR54 gene r10407968. We observed a significant difference in estradiol (p = 0.023, p = 0.012) after comparing the values of LH, FSH, estradiol, progesterone, and testosterone among the three genotypes of rs4889 and rs5780218. The KiSS-1 rs4889 CC genotype and rs5780218 AA genotype showed significantly higher estradiol levels compared with the other two genotypes.

CONCLUSIONS

These results suggest that kisspeptin plays a potential role in the etiology of PCOS.

Does Serum LH Level Influence IVF Outcomes in Women with PCOS Undergoing GnRH-Antagonist Stimulation: A Novel Indicator

Objective: To explore the influence of LH levels on the IVF/ICSI outcomes in women with PCOSundergoing GnRH-antagonist stimulation protocol. Methods: A total of 142 IVF/ICSI patients in which the females were diagnosed with PCOS and underwent GnRH-antagonist protocol for ovarian stimulation were enrolled. Patients were divided into three groups based on basal LH (bLH) level, LH level on trigger day (hLH), and the ratio of hLH/bLH. The LH levels detected on different days in the stimulation cycle as well as their relationships with the IVF/ICSI outcomes were investigated. The main outcomes we observed were the number of oocytes retrieved, the cumulative chemical pregnancy rate, clinical pregnancy rate, and live birth rate. Other factors included the number of normally fertilized oocytes (2PN), top-quality embryo rate, and total Gn dose. Results: There was no significant difference in the included outcomes and baseline characteristics among different groups based on bLH levels. When patients were grouped according to hLH levels (≤2 mIU/mL, 2–5 mIU/mL and ≥5 mIU/mL), we found decreased levels of basal FSH and LH in the group of hLH ≤ 2 mIU/mL than the other two groups. Then the ratio of hLH/bLH was calculated for each patient. Patients with hLH/bLH ≥ 1 had a higher top-quality embryo rate than those with hLH/bLH between 0.5 and 1.0. Nevertheless, the cumulative clinical pregnancy rate was significantly higher in the hLH/bLH ≤ 0.5 group than in the other two groups. Conclusions: The study proposed the hLH/bLH ratio as a potential in predicting the influence of LH level on the embryo development potential as well as pregnancy outcomes in women with PCOS undergoing GnRH-antagonist stimulation cycles.

Treatments targeting neuroendocrine dysfunction in polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age and is the leading cause of anovulatory subfertility. Increased gonadotrophin releasing hormone (GnRH) pulsatility in the hypothalamus results in preferential luteinizing hormone (LH) secretion from the pituitary gland, leading to ovarian hyperandrogenism and oligo/anovulation. The resultant hyperandrogenism reduces negative feedback from sex steroids such as oestradiol and progesterone to the hypothalamus, and thus perpetuates the increase in GnRH pulsatility. GnRH neurons do not have receptors for oestrogen, progesterone, or androgens, and thus the disrupted feedback is hypothesized to occur via upstream neurons. Likely candidates for these upstream regulators of GnRH neuronal pulsatility are Kisspeptin, Neurokinin B (NKB), and Dynorphin neurons (termed KNDy neurons). Growing insight into the neuroendocrine dysfunction underpinning the heightened GnRH pulsatility seen in PCOS has led to research on the use of pharmaceutical agents that specifically target the activity of these KNDy neurons to attenuate symptoms of PCOS. This review aims to highlight the neuroendocrine abnormalities that lead to increased GnRH pulsatility in PCOS, and outline data on recent therapeutic advancements that could potentially be used to treat PCOS. Emerging evidence has investigated the use of neurokinin 3 receptor (NK3R) antagonists as a method of reducing GnRH pulsatility and alleviating features of PCOS such as hyperandrogenism. We also consider other potential mechanisms by which increased GnRH pulsatility is controlled, which could form the basis of future avenues of research.

Serum kisspeptin, leptin, neuropeptide Y, and neurokinin B levels in adolescents with polycystic ovary syndrome

OBJECTIVES

Polycystic ovary syndrome (PCOS) is characterized by ovarian dysfunction, clinical and/or biochemical hyperandrogenism, and polycystic ovaries. Its pathogenesis is still unclear. This study aimed to investigate the relationship between kisspeptin, leptin, neuropeptide Y (NPY), and neurokinin B (NKB) levels for evaluating the pathogenesis of PCOS.

METHODS

Levels of these parameters were analyzed in 20 patients with PCOS, and 16 healthy adolescents.

RESULTS

Serum NPY levels were significantly higher in the obese and non-obese PCOS group (p<0.01). There was a negative correlation between the kisspeptin and the NKB levels (p<0.01) in the PCOS group but not in the control group. This negative correlation was also found in both PCOS groups (p<0.01). In the obese PCOS group, serum kisspeptin levels were significantly lower than the control and non-obese PCOS groups (p<0.05) although serum leptin and NPY levels were significantly higher in the obese PCOS group (p<0.01).

CONCLUSIONS

The high NPY levels in both obese and non-obese patients with PCOS indicate that NPY plays a role in the pathogenesis independently from obesity. Significantly high leptin and low kisspeptin levels in the obese PCOS group suggested that they may be associated with obesity rather than PCOS.

Neuroendocrine Determinants of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women and a major cause of anovulatory infertility. A diagnosis of PCOS is established based the presence of two out of three clinical symptoms, which are criteria accepted by the ESHRE/ASRM (European Society of Human Reproduction and Embryology/American Society for Reproductive Medicine). Gonadotropin-releasing hormone (GnRH) is responsible for the release of luteinizing hormone, and follicle stimulating hormone from the pituitary and contributes a leading role in controlling reproductive function in humans. The goal of this review is to present the current knowledge on neuroendocrine determinations of PCOS. The role of such neurohormones as GnRH, and neuropeptides kisspeptin, neurokinin B, phoenixin-14, and galanin is discussed in this aspect. Additionally, different neurotransmitters (gamma-aminobutyric acid (GABA), glutamate, serotonin, dopamine, and acetylcholine) can also be involved in neuroendocrine etiopathogenesis of PCOS. Studies have shown a persistent rapid GnRH pulse frequency in women with PCOS present during the whole ovulatory cycle. Other studies have proved that patients with PCOS are characterized by higher serum kisspeptin levels. The observations of elevated serum kisspeptin levels in PCOS correspond with the hypothesis that overactivity in the kisspeptin system is responsible for hypothalamic-pituitary-gonadal axis overactivity. In turn, this causes menstrual disorders, hyperandrogenemia and hyperandrogenism. Moreover, abnormal regulation of Neurokinin B (NKB) is also suspected of contributing to PCOS development, while NKB antagonists are used in the treatment of PCOS leading to reduction in Luteinizing hormone (LH) concentration and total testosterone concentration. GnRH secretion is regulated not only by kisspeptin and neurokinin B, but also by other neurohormones, such as phoenixin-14, galanin, and Glucagon-like peptide-1 (GLP-1), that have favorable effects in counteracting the progress of PCOS. A similar process is associated with the neurotransmitters such as GABA, glutamate, serotonin, dopamine, and acetylcholine, as well as the opioid system, which may interfere with secretion of GnRH, and therefore, influence the development and severity of symptoms in PCOS patients. Additional studies are required to explain entire, real mechanisms responsible for PCOS neuroendocrine background.

Neuropeptides as regulators of the hypothalamus-pituitary-gonadal (HPG) axis activity and their putative roles in stress-induced fertility disorders

Neuropeptides being regulators of the hypothalamus-pituitary-adrenal (HPA) axis activity, also affect the function of the hypothalamus-pituitary-gonadal (HPG) axis by regulating gonadotrophin-releasing hormone (GnRH) secretion from hypothalamic neurons. Here, we review the available data on how neuropeptides affect HPG axis activity directly or indirectly via their influence on the HPA axis. The putative role of neuropeptides in stress-induced infertility, such as polycystic ovary syndrome, is also described. This review discusses both well-known neuropeptides (i.e., kisspeptin, Kp; oxytocin, OT; arginine-vasopressin, AVP) and more recently discovered peptides (i.e., relaxin-3, RLN-3; nesfatin-1, NEFA; phoenixin, PNX; spexin, SPX). For the first time, we present an up-to-date review of all published data regarding interactions between the aforementioned neuropeptide systems. The reviewed literature suggest new pathophysiological mechanisms leading to fertility disturbances that are induced by stress.

Kisspeptin-neuron control of LH pulsatility and ovulation

Feedback from oestradiol (E2) plays a critical role in the regulation of major events in the physiological menstrual cycle including the release of gonadotrophins to stimulate follicular growth, and the mid-cycle luteinising hormone (LH) surge that leads to ovulation. E2 predominantly exerts its action via oestrogen receptor-alpha (ERα), however, as gonadotrophin releasing hormone (GnRH) neurons lack ERα, E2-feedback is posited to be indirectly mediated via upstream neurons. Kisspeptin (KP) is a neuropeptide expressed in hypothalamic KP-neurons that control GnRH secretion and plays a key role in the central mechanism regulating the hypothalamic-pituitary-gonadal (HPG) axis. In the rodent arcuate (ARC) nucleus, KP is co-expressed with Neurokinin B and Dynorphin; and thus, these neurons are termed 'Kisspeptin-Neurokinin B-Dynorphin' (KNDy) neurons. ARC KP-neurons function as the 'GnRH pulse generator' to regulate GnRH pulsatility, as well as mediating negative feedback from E2. A second KP neuronal population is present in the rostral periventricular area of the third ventricle (RP3V), which includes anteroventral periventricular (AVPV) nucleus and preoptic area neurons. These RP3V KP-neurons mediate positive feedback to induce the mid-cycle luteinising hormone (LH) surge and subsequent ovulation. Here, we describe the role of KP-neurons in these two regions in mediating this differential feedback from oestrogens. We conclude by considering reproductive diseases for which exploitation of these mechanisms could yield future therapies.

Prenatal Androgen Exposure Alters KNDy Neurons and Their Afferent Network in a Model of Polycystic Ovarian Syndrome

Polycystic ovarian syndrome (PCOS), the most common endocrinopathy affecting women worldwide, is characterized by elevated luteinizing hormone (LH) pulse frequency due to the impaired suppression of gonadotrophin-releasing hormone (GnRH) release by steroid hormone negative feedback. Although neurons that co-express kisspeptin, neurokinin B, and dynorphin (KNDy cells) were recently defined as the GnRH/LH pulse generator, little is understood about their role in the pathogenesis of PCOS. We used a prenatal androgen-treated (PNA) mouse model of PCOS to determine whether changes in KNDy neurons or their afferent network underlie altered negative feedback. First, we identified elevated androgen receptor gene expression in KNDy cells of PNA mice, whereas progesterone receptor and dynorphin gene expression was significantly reduced, suggesting elevated androgens in PCOS disrupt progesterone negative feedback via direct actions upon KNDy cells. Second, we discovered GABAergic and glutamatergic synaptic input to KNDy neurons was reduced in PNA mice. Retrograde monosynaptic tract-tracing revealed a dramatic reduction in input originates from sexually dimorphic afferents in the preoptic area, anteroventral periventricular nucleus, anterior hypothalamic area and lateral hypothalamus. These results reveal 2 sites of neuronal alterations potentially responsible for defects in negative feedback in PCOS: changes in gene expression within KNDy neurons, and changes in synaptic inputs from steroid hormone-responsive hypothalamic regions. How each of these changes contribute to the neuroendocrine phenotype seen in in PCOS, and the role of specific sets of upstream KNDy afferents in the process, remains to be determined.

The role of polymorphism in various potential genes on polycystic ovary syndrome susceptibility and pathogenesis

Polycystic ovary syndrome (PCOS) is the most common endocrinopathies affecting the early reproductive age in women, whose pathophysiology perplexes many researchers till today. This syndrome is classically categorized by hyperandrogenism and/or hyperandrogenemia, menstrual and ovulatory dysfunction, bulky multi follicular ovaries on Ultrasonography (USG), and metabolic abnormalities such as hyperinsulinemia, dyslipidemia, obesity. The etiopathogenesis of PCOS is not fully elucidated, but it seems that the hypothalamus-pituitary-ovarian axis, ovarian, and/or adrenal androgen secretion may contribute to developing the syndrome. Infertility and poor reproductive health in women's lives are highly associated with elevated levels of androgens. Studies with ovarian theca cells taken from PCOS women have demonstrated increased androgen production due to augmented ovarian steroidogenesis attributed to mainly altered expression of critical enzymes (Cytochrome P450 enzymes: CYP17, CYP21, CYP19, CYP11A) in the steroid hormone biosynthesis pathway. Despite the heterogeneity of PCOS, candidate gene studies are the widely used technique to delineate the genetic variants and analyze for the correlation of androgen biosynthesis pathway and those affecting the secretion or action of insulin with PCOS etiology. Linkage and association studies have predicted the relationship between genetic variants and PCOS risk among families or populations. Several genes have been proposed as playing a role in the etiopathogenesis of PCOS, and the presence of mutations and/or polymorphisms has been discovered, which suggests that PCOS has a vital heritable component. The following review summarizes the influence of polymorphisms in crucial genes of the steroidogenesis pathway leading to intraovarian hyperandrogenism which can result in PCOS.

Randomized Controlled Trial of Neurokinin 3 Receptor Antagonist Fezolinetant for Treatment of Polycystic Ovary Syndrome

CONTEXT

Polycystic ovary syndrome (PCOS), a highly prevalent endocrine disorder characterized by hyperandrogenism, is the leading cause of anovulatory infertility.

OBJECTIVE

This proof-of-concept study evaluated clinical efficacy and safety of the neurokinin 3 (NK3) receptor antagonist fezolinetant in PCOS.

METHODS

This was a phase 2a, randomized, double-blind, placebo-controlled, multicenter study (EudraCT 2014-004409-34). The study was conducted at 5 European clinical centers. Women with PCOS participated in the study. Interventions included fezolinetant 60 or 180 mg/day or placebo for 12 weeks. The primary efficacy end point was change in total testosterone. Gonadotropins, ovarian hormones, safety and tolerability were also assessed.

RESULTS

Seventy-three women were randomly assigned, and 64 participants completed the study. Adjusted mean (SE) changes in total testosterone from baseline to week 12 for fezolinetant 180 and 60 mg/day were -0.80 (0.13) and -0.39 (0.12) nmol/L vs -0.05 (0.10) nmol/L with placebo (P < .001 and P < .05, respectively). Adjusted mean (SE) changes from baseline in luteinizing hormone (LH) for fezolinetant 180 and 60 mg/d were -10.17 (1.28) and -8.21 (1.18) vs -3.16 (1.04) IU/L with placebo (P < .001 and P = .002); corresponding changes in follicle-stimulating hormone (FSH) were -1.46 (0.32) and -0.92 (0.30) vs -0.57 (0.26) IU/L (P = .03 and P = .38), underpinning a dose-dependent decrease in the LH-to-FSH ratio vs placebo (P < .001). Circulating levels of progesterone and estradiol did not change significantly vs placebo (P > .10). Fezolinetant was well tolerated.

CONCLUSION

Fezolinetant had a sustained effect to suppress hyperandrogenism and reduce the LH-to-FSH ratio in women with PCOS.

Kisspeptin levels in relation to sex hormone profile among PCOS patients

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common endocrine disease among women in the reproductive age that is associated with consequences such as insulin resistance and hyperandrogenemia. This study was aimed to assess the association of sex hormone profile and kisspeptin levels in PCOS women in Gorgan, Iran.

METHODS

In this case-control study, 43 women with diagnosed PCOS between the ages of 15 and 37 years and 40 healthy demographically matched controls were recruited. Sex hormone profile and kisspeptin levels were measured in these subjects using ELISA assay kits.

RESULTS

Follicle stimulating hormone (FSH), sex hormone binding globulin (SHBG), and kisspeptin levels were significantly lower in cases than in controls. Luteinizing hormone (LH), free-testosterone (FT), 17-OH-progesterone (17-OH-P), dehydroepiandrosterone sulfate (DHEA-S), estradiol (E2), and free androgen index (FAI) were higher in PCOS significantly. There was a significant positive correlation between kisspeptin levels and LH and E2 in cases (p = 0.037 and p = 0.024, respectively). The results of the regression analysis have shown a significant association between the LH and kisspeptin concentrations in PCOS group (r = 0.275, p = 0.037).

CONCLUSION

PCOS patients had lower plasma kisspeptin level that was positively correlated with LH and estradiol levels. Also, higher levels of free androgens were demonstrated in these patients. It is suggested that kisspeptin may be involved in complex interactions of the sex hormone endocrine system of PCOS.

Clinical and biochemical discriminants between functional hypothalamic amenorrhoea (FHA) and polycystic ovary syndrome (PCOS)

BACKGROUND

Secondary oligo/amenorrhoea occurs in 3%-5% of women of reproductive age. The two most common causes are polycystic ovary syndrome (PCOS) (2%-13%) and functional hypothalamic amenorrhoea (FHA) (1%-2%). Whilst both conditions have distinct pathophysiology and their diagnosis is supported by guidelines, in practice, differentiating these two common causes of menstrual disturbance is challenging. Moreover, both diagnoses are qualified by the need to first exclude other causes of menstrual disturbance.

AIM

To review clinical, biochemical and radiological parameters that could aid the clinician in distinguishing PCOS and FHA as a cause of menstrual disturbance.

RESULTS

FHA is uncommon in women with BMI > 24 kg/m² , whereas both PCOS and FHA can occur in women with lower BMIs. AMH levels are markedly elevated in PCOS; however, milder increases may also be observed in FHA. Likewise, polycystic ovarian morphology (PCOM) is more frequently observed in FHA than in healthy women. Features that are differentially altered between PCOS and FHA include LH, androgen, insulin, AMH and SHBG levels, endometrial thickness and cortisol response to CRH. Other promising diagnostic tests with the potential to distinguish these two conditions pending further study include assessment of 5-alpha-reductase activity, leptin, INSL3, kisspeptin and inhibin B levels.

CONCLUSION

Further data directly comparing the discriminatory potential of these markers to differentiate PCOS and FHA in women with secondary amenorrhoea would be of value in defining an objective probability for PCOS or FHA diagnosis.

Thyroid, Adrenal, PRL Impairments and Ovarian Function

Endocrine axes (prolactin, thyroid and adrenal axes) directly and indirectly modulate and drive human female central functions, mainly behavior and reproduction. Though having distinct abilities, they greatly act both at peripheral as well as at neuroendocrine levels, so as to participate in the control of reproduction. Any event that changes these balanced activities produces specific peripheral signals that induce abnormal functions centrally, thus triggering menstrual disorders such as oligomenorrhea or amenorrhea. It is clear that the knowledge of the relationships that exist between the different endocrine axes becomes essential for the choice of therapeutical approach. This review aims to focus on the main aspects of the physiopathology of the endocrine diseases that might be at the basis of that interference with female reproductive capacity.

Serum kisspeptin levels correlated with anti-mullerian hormone levels in women with and without polycystic ovarian syndrome

MATERIALS AND METHODS

This was a prospective, cross-sectional, comparative study that included 70 women with PCOS and 58 non PCOS controls. PCOS patients were diagnosed according to the Rotterdam criteria. Age, body mass index (BMI), number of menstrual cycles per year, and the Ferriman-Gallwey Score were determined for each woman. Serum levels of kisspeptin, follicle stimulating hormone (FSH), luteinizing hormone (LH), thyroid stimulating hormone (TSH), estradiol, total testosterone, dehydroepiandrosterone sulfate (DHEA-S), AMH, fasting glucose and insulin were determined.

RESULTS

Women with PCOS were younger (p < .001), with higher BMI (p = .027) and glucose values (p < .001); while displaying less number of menstrual cycles per year (p < .001). Although serum kisspeptin levels were similar in both groups, age was negatively (r= -0.33, p = .00018) and serum AMH levels were positively correlated (r = 0.25, p = .0039) with the serum kisspeptin levels in women with the PCOS. After adjusting for age, serum kisspeptin levels were comparable in both groups (p > .05). Serum LH, AMH, DHEA-S and total testosterone glucose, insulin levels and HOMA-IR values were significantly higher in women with PCOS as compared to controls (all p < .05).

CONCLUSIONS

Serum kisspeptin levels were similar in women with and without PCOS but positively correlated with AMH serum levels in PCOS women.

Clinical Applications of Serum Anti-Müllerian Hormone Measurements in Both Males and Females: An Update

Infertility is one of the most common non-communicable diseases, affecting both men and women equally. Ovarian reserve, the number of primordial follicles in the ovaries is believed to be the most important determinants for female fertility. Anti-Müllerian hormone (AMH) secreted from granulosa cells of growing follicles is recognized as the most important biomarker for ovarian reserve. Ovarian reserve models have been developed using AMH and other hormonal indicators, thus childbearing plans and reproductive choices could be arranged by women. In assisted reproductive technology cycles, measurement of AMH helps to predict ovarian response and guide recombinant follicle-stimulating hormone dosing in women. Serum AMH level is increasingly being recognized as a potential surrogate marker for polycystic ovarian morphology, one of the criteria for diagnosis of polycystic ovarian syndrome. AMH is also secreted by Sertoli cells of testes in men, and AMH measurements in the prediction of surgical sperm recovery rate in men have also been investigated. AMH levels are significantly higher in boys than in girls before puberty. Therefore, serum levels of AMH in combination with testosterone is used for the differential diagnosis of disorders of sex development, anorchia, non-obstructive azoospermia, and persistent Müllerian duct syndrome. Recently, serum AMH measurements have also been used in fertility preservation programs in oncofertility, screening for granulosa cell tumors, and prediction of menopause applications. In this review, we will focus on clinical application of AMH in fertility assessments for healthy men and women, as well as for cancer patients.

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Anti-Müllerian hormone (AMH) plays a key role in models assessing ovarian reserve

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AMH is used for the differential diagnosis of disorders of sex development

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AMH provides a molecular marker for related fertility and infertility disorders

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An international standard will aid in the development of various AMH assays

AMH Is a Good Predictor of Metabolic Risk in Women with PCOS: A Cross-Sectional Study

OBJECTIVE

The relationship between metabolic risk and ovarian function is ambiguous. This retrospective study analyzed the medical records of 461 PCOS patients collected between January 2019 and June 2020 to investigate the relationship between serum anti-Müllerian hormone (AMH) and parameters of metabolic risk in the population with polycystic ovary syndrome (PCOS).

METHODS

A total of 461 PCOS patients aged 20-40 years were included and stratified into four groups according to the AMH level. The association between AMH and the parameters related to metabolic risk in these groups was compared, and the discrepancies were further explored. Binary logistic regression was performed to examine the risk factors of HOMA-IR. The values of AMH that best predicted the risk of HOMA-IR were also analyzed by ROC curves.

RESULTS

AMH was negatively associated with HOMA-IR (odds ratio (OR) -0.279, 95% confidence interval (CI) -0.36 to -0.20), fasting insulin (OR -0.282, 95% CI -0.36 to -0.20), 1-hour postprandial insulin (OR -0.184, 95% CI -0.28 to -0.11), 2-hour postprandial insulin (-0.180, 95%CI -0.28 to -0.11), 3-hour postprandial insulin (OR -0.198, 95% CI -0.30 to -0.13), waist-hip ratio (OR -0.235, 95% CI -0.31 to -0.14), and body mass index (OR -0.350, 95% CI -0.43 to -0.27). There was no statistically significant relationship between blood pressure, serum glucose profile, or lipid levels and AMH. Binary logistic regression showed that AMH protected against the occurrence of PCOS patients (OR: 0.835, 0.776, and 0.898). For the prediction of HOMA-IR, AMH had an AUC-ROC of 0.704 (95% CI 0.652-0.755) with a cutoff value of 7.81 mmol/L, a sensitivity of 70.3%, and a specificity of 70.1%.

CONCLUSIONS

Higher AMH levels were significantly associated with a lower insulin profile and might be a useful predictor for HOMA-IR in PCOS patients.

Effect of Vitex agnus-castus ethanolic extract on hypothalamic KISS-1 gene expression in a rat model of polycystic ovary syndrome

OBJECTIVE

Polycystic ovary syndrome (PCOS) is an endocrine system disruption that affects 6-10% of women. Some studies have reported the effect of Vitex agnus-castus (Vitagnus) on the hypothalamic-pituitary-gonad axis (HPG). This study was conducted to investigate Vitagnus effect on the expression of kisspeptin gene in a rat model of PCOS.

MATERIALS AND METHODS

Thirty-two female rats were distributed into: control, Vitagnus-treatment (365 mg/kg for 30 days), PCOS (Letrozole for 28 days) and PCOS animals treated with Vitagnus (30 days of Vitagnus after PCOS induction). At the end of the treatments, serum and ovaries were collected for analysis. Expression level of KISS-1 gene in the hypothalamus was investigated, using Real-Time-PCR.

RESULTS

In the PCOS group compared to control, FSH, progesterone and estradiol levels were decreased, whereas testosterone and LH levels were significantly increased. No significant changes were observed in the Vitagnus-treated animals in compare to control. However, Vitagnus treatment in the PCOS group, resulted in a raise in progesterone, estrogen and FSH levels and a reduction in the levels of testosterone and LH. Quantitative gene expression analysis showed that PCOS induction resulted in over-expression of KISS-1 gene, however, Vitagnus treatment reduced this up-regulated expression to normal level.

CONCLUSION

In conclusion, our results indicated that Vitagnus extract inhibited downregulation of KISS-1 gene in the hypothalamus of PCOS rats. Because of the master role of kisspeptin in adjusting the HPG axis, Vitagnus is likely to show beneficial effects in the treatment of PCOS via regulation of kisspeptin expression. This finding indicates a new aspect of Vitagnus effect and may be considered in its clinical applications.

Kisspeptin and LH pulsatility in patients with functional hypothalamic amenorrhea

PURPOSE

Functional hypothalamic amenorrhea (FHA) occurs in response to exaggerated stressors with or without body weight loss. Various hormones, neurotransmitters, and neuromodulators are involved in the control of GnRH and kisspeptin is one of them. Our study aimed to evaluate the putative temporal coupling between kisspeptin and GnRH-induced LH pulsatile secretion.

METHODS

In total, 71 patients with FHA were selected for this study. All patients undergo to a pulsatility study for LH and kisspeptin evaluation (120 min, sampling every 10 min), and to an endocrine evaluation for prolactin (PRL), estradiol (E2), androstenedione (A), 17-hydroxy-progesterone (17OHP), TSH, fT3, fT4, insulin, cortisol and testosterone (T), glucose, total cholesterol, triglycerides.

RESULTS

Our data demonstrated kisspeptin and LH pulsatile secretions and that both hormones are co-secreted and temporally coupled at time 0 (p < 0.05). When patients were subdivided in hypo-LH (≤3 mIU/ml, n = 58) and normo-LH (>3 mIU/ml, n = 13), more insights were observed on the specific correlations of metabolic and hormone profiles with pulsatility indexes of LH and kisspeptin.

CONCLUSIONS

Our study demonstrated the presence of a distinct kisspeptin episodic secretion in patients with FHA, and showed the temporally coupling of kisspeptin with LH secretory episodes thus supporting that though in amenorrhea, the reproductive axis is still relying on kisspeptin to drive GnRH discharge. In addition, correlations among hormonal data sustain the hypothesis that stress-induced compensatory events are the main direct and indirect promoters of the reproductive blockade in patients affected by FHA.

In Search of New Therapeutics-Molecular Aspects of the PCOS Pathophysiology: Genetics, Hormones, Metabolism and Beyond

In a healthy female reproductive system, a subtle hormonal and metabolic dance leads to repetitive cyclic changes in the ovaries and uterus, which make an effective ovulation and potential implantation of an embryo possible. However, that is not so in the case of polycystic ovary syndrome (PCOS), in which case the central mechanism responsible for entraining hormonal and metabolic rhythms during the menstrual cycle is notably disrupted. In this review we provide a detailed description of the possible scenario of PCOS pathogenesis. We begin from the analysis of how a set of genetic disorders related to PCOS leads to particular malfunctions at a molecular level (e.g., increased enzyme activities of cytochrome P450 (CYP) type 17A1 (17α-hydroxylase), 3β-HSD type II and CYP type 11A1 (side-chain cleavage enzyme) in theca cells, or changes in the expression of aquaporins in granulosa cells) and discuss further cellular- and tissue-level consequences (e.g., anovulation, elevated levels of the advanced glycation end products in ovaries), which in turn lead to the observed subsequent systemic symptoms. Since gene-editing therapy is currently out of reach, herein special emphasis is placed on discussing what kinds of drug targets and which potentially active substances seem promising for an effective medication, acting on the primary causes of PCOS on a molecular level.

Animal Models to Understand the Etiology and Pathophysiology of Polycystic Ovary Syndrome

More than 1 out of 10 women worldwide are diagnosed with polycystic ovary syndrome (PCOS), the leading cause of female reproductive and metabolic dysfunction. Despite its high prevalence, PCOS and its accompanying morbidities are likely underdiagnosed, averaging > 2 years and 3 physicians before women are diagnosed. Although it has been intensively researched, the underlying cause(s) of PCOS have yet to be defined. In order to understand PCOS pathophysiology, its developmental origins, and how to predict and prevent PCOS onset, there is an urgent need for safe and effective markers and treatments. In this review, we detail which animal models are more suitable for contributing to our understanding of the etiology and pathophysiology of PCOS. We summarize and highlight advantages and limitations of hormonal or genetic manipulation of animal models, as well as of naturally occurring PCOS-like females.

Kisspeptin and neurokinin B analogs use in gynecological endocrinology: where do we stand?

BACKGROUND

Recent studies have found that kisspeptin/neurokinin B/dynorphin neurons (KNDy neurons) in the infundibular nucleus play a crucial role in the reproductive axis. Analogs, both agonists and antagonists, of kisspeptin and neurokinin B (NKB) are particularly important in explaining the physiological role of KNDy in the reproductive axis in animals. The use of kisspeptin and NKB analogs has helped elucidate the regulators of the hypothalamic reproductive axis.

PURPOSE

This review describes therapeutic uses of Kiss-1 and NKB agonists, most obviously the use of kisspeptin agonists in the treatment for infertility and the induction of ovulation. Kisspeptin antagonists may have potential clinical applications in patients suffering from diseases associated with enhanced LH pulse frequency, such as polycystic ovary syndrome or menopause. The inhibition of pubertal development using Kiss antagonists may be used as a therapeutic option in precocious puberty. Kisspeptin antagonists have been found capable of inhibiting ovulation and have been proposed as novel contraceptives. Hypothalamic amenorrhea and delayed puberty are conditions in which normalization of LH secretion may potentially be achieved by treatment with both kisspeptin and NKB agonists. NKB antagonists are used to treat vasomotor symptoms in postmenopausal women, providing rapid relief of symptoms while supplanting the need for exogenous estrogen exposure.

CONCLUSIONS

There is a wide spectrum of therapeutic uses of Kiss-1 and NKB agonists, including the management of infertility, treatment for PCOS, functional hypothalamic amenorrhea or postmenopausal vasomotor symptoms, as well as contraceptive issues. Nevertheless, further research is needed before kisspeptin and NKB analogs are fully incorporated in clinical practice.

Abnormal GnRH Pulsatility in Polycystic Ovary Syndrome: Recent Insights

Although the fundamental symptoms of polycystic ovary syndrome (PCOS) relate most directly to ovarian dysfunction, central neuroendocrine systems play a prominent role in its pathophysiology. Gonadotropin-releasing hormone (GnRH) pulse generator resistance to negative feedback contributes to rapid GnRH pulse secretion, which promotes gonadotropin abnormalities that foster ovarian hyperandrogenemia and ovulatory dysfunction. The causes of GnRH neuron dysfunction, however, have remained enigmatic. In this review, we highlight a number of recent preclinical and clinical studies pertinent to the neuroendocrine abnormalities of PCOS, including those that have provided important insights into the relevance of animal models with PCOS-like features, the potential roles of kisspeptin and γ-aminobutyric acid (GABA)-ergic neurons, and the potential role of anti-Müllerian hormone.

Long-term treatment with α-lipoic acid and myo-inositol positively affects clinical and metabolic features of polycystic ovary syndrome

The aim of this retrospective study was to evaluate the effects of a long-term treatment with α-lipoic acid (ALA) combined with myo-inositol (MI) on clinical and metabolic features of women with polycystic ovary syndrome (PCOS). Fifty-seven women with PCOS and a history of oligoamenorrhea were treated with MI and ALA (800 mg + 2000 mg per day). Forty-four of them had complete clinical charts and were considered eligible for the study. Information about cycle length and body mass index (BMI) was checked after 6, 12, and 24 months. After 12 months ovarian volume, total testosterone plasma levels and changes in hirsutism were also evaluated. The metabolic parameters were evaluated in 16 women after 6 and 18 months of the treatment. Cycle length was significantly reduced at 6 (p < .001), 12, and 24 months of treatment (p < .01). BMI showed a reduction only at 6 months (p < .05), thereafter returning similar to the basal values. No changes of testosterone and ovarian volume were observed. HOMA-IR and fasting insulin were unchanged, but the insulin response to a 3 h OGTT was improved after 6 (p < .01) and 18 months (p < .05) of treatment. No individual suffered from any adverse event. In conclusion, the combination of ALA and MI showed to be useful as long-term therapy in PCOS women, providing a normalization of the menstrual cycle and an amelioration of insulin levels with a high tolerability.

The Correlation between Hormonal Disturbance in PCOS Women and Serum Level of Kisspeptin

BACKGROUND

Kisspeptin is a neuropeptide that upregulates gonadotropin-releasing hormone (GnRH) secretion. It is an essential element for the luteinizing hormone (LH) surge and ovulation. Women with polycystic ovary syndrome (PCOS) expose alteration in both GnRH and LH secretion levels.

OBJECTIVE

This paper aims to evaluate serum kisspeptin levels in healthy and polycystic ovarian syndrome women. Furthermore, it investigates the effect of obesity and age on circulating kisspeptin levels in both normal and PCOS women. Moreover, it points out the correlation between kisspeptin and other hormonal parameters. Methods and Patients. One hundred women (60 are with PCOS and 40 are normal) were enrolled in the study. Five milliliter samples of blood from all the patients and control women were obtained twice during the menstrual cycle. All the study samples were classified depending on the age factor for several subgroups.

RESULTS

Kisspeptin levels were higher in PCOS patients than those in the normal group. Kisspeptin correlated with serum free testosterone level (r=0.26). In healthy women, preovulatory kisspeptin levels were higher than follicular kisspeptin levels (P < 0.05), while this difference was insignificant in PCOS patients. The variation in serum kisspeptin levels between overweight/obese and normal-weight women was insignificant. In normal women, serum kisspeptin levels were higher in women >35 years than those <24 years at (P=0.03).

CONCLUSION

The serum kisspeptin level is higher in PCOS women. Its levels fluctuate during the menstrual cycle, but these fluctuations are disturbed in PCOS women. The effect of BMI on serum kisspeptin levels is insignificant, and kisspeptin serum levels increase with age.

Neuroendocrine Impairments of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a prevalent and distressing disorder of largely unknown etiology. Although PCOS defined by ovarian dysfunction, accumulating evidence supports a critical role for the brain in the ontogeny and pathophysiology of PCOS. A critical pathological feature of PCOS is impaired gonadal steroid hormone negative feedback to the GnRH neuronal network in the brain that regulates fertility. This impairment is associated with androgen excess, a cardinal feature of PCOS. Impaired steroid hormone feedback to GnRH neurons is thought to drive hyperactivity of the neuroendocrine axis controlling fertility, leading to a vicious cycle of androgen excess and reproductive dysfunction. Decades of clinical research have been unable to uncover the mechanisms underlying this impairment, because of the extreme difficulty in studying the brain in humans. It is only recently, with the development of preclinical models of PCOS, that we have begun to unravel the role of the brain in the development and progression of PCOS. Here, we provide a succinct overview of what is known about alterations in the steroid hormone-sensitive GnRH neuronal network that may underlie the neuroendocrine defects in clinical PCOS, with a particular focus on those that may contribute to impaired progesterone negative feedback, and the likely role of androgens in driving this impairment.

The Mechanism of Androgen Actions in PCOS Etiology

Polycystic ovary syndrome (PCOS) is the most common endocrine condition in reproductive-age women. By comprising reproductive, endocrine, metabolic and psychological features—the cause of PCOS is still unknown. Consequently, there is no cure, and management is persistently suboptimal as it depends on the ad hoc management of symptoms only. Recently it has been revealed that androgens have an important role in regulating female fertility. Androgen actions are facilitated via the androgen receptor (AR) and transgenic Ar knockout mouse models have established that AR-mediated androgen actions have a part in regulating female fertility and ovarian function. Considerable evidence from human and animal studies currently reinforces the hypothesis that androgens in excess, working via the AR, play a key role in the origins of polycystic ovary syndrome (PCOS). Identifying and confirming the locations of AR-mediated actions and the molecular mechanisms involved in the development of PCOS is critical to provide the knowledge required for the future development of innovative, mechanism-based interventions for the treatment of PCOS. This review summarises fundamental scientific discoveries that have improved our knowledge of androgen actions in PCOS etiology and how this may form the future development of effective methods to reduce symptoms in patients with PCOS.

The Role of the Brain in the Pathogenesis and Physiology of Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder, affecting at least 10% of women of reproductive age. PCOS is typically characterized by the presence of at least two of the three cardinal features of hyperandrogenemia (high circulating androgen levels), oligo- or anovulation, and cystic ovaries. Hyperandrogenemia increases the severity of the condition and is driven by increased luteinizing hormone (LH) pulse secretion from the pituitary. Indeed, PCOS women display both elevated mean LH levels, as well as an elevated frequency of LH pulsatile secretion. The abnormally high LH pulse frequency, reflective of a hyperactive gonadotropin-releasing hormone (GnRH) neural circuit, suggests a neuroendocrine basis to either the etiology or phenotype of PCOS. Several studies in preclinical animal models of PCOS have demonstrated alterations in GnRH neurons and their upstream afferent neuronal circuits. Some rodent PCOS models have demonstrated an increase in GnRH neuron activity that correlates with an increase in stimulatory GABAergic innervation and postsynaptic currents onto GnRH neurons. Additional studies have identified robust increases in hypothalamic levels of kisspeptin, another potent stimulator of GnRH neurons. This review outlines the different brain and neuroendocrine changes in the reproductive axis observed in PCOS animal models, discusses how they might contribute to either the etiology or adult phenotype of PCOS, and considers parallel findings in PCOS women.

Polycystic Ovary Syndrome: Pathophysiology, Presentation, and Treatment With Emphasis on Adolescent Girls

Polycystic ovary syndrome (PCOS) is a heterogeneous disorder characterized by hyperandrogenism and chronic anovulation. Depending on diagnostic criteria, 6% to 20% of reproductive aged women are affected. Symptoms of PCOS arise during the early pubertal years. Both normal female pubertal development and PCOS are characterized by irregular menstrual cycles, anovulation, and acne. Owing to the complicated interwoven pathophysiology, discerning the inciting causes is challenging. Most available clinical data communicate findings and outcomes in adult women. Whereas the Rotterdam criteria are accepted for adult women, different diagnostic criteria for PCOS in adolescent girls have been delineated. Diagnostic features for adolescent girls are menstrual irregularity, clinical hyperandrogenism, and/or hyperandrogenemia. Pelvic ultrasound findings are not needed for the diagnosis of PCOS in adolescent girls. Even before definitive diagnosis of PCOS, adolescents with clinical signs of androgen excess and oligomenorrhea/amenorrhea, features of PCOS, can be regarded as being "at risk for PCOS." Management of both those at risk for PCOS and those with a confirmed PCOS diagnosis includes education, healthy lifestyle interventions, and therapeutic interventions targeting their symptoms. Interventions can include metformin, combined oral contraceptive pills, spironolactone, and local treatments for hirsutism and acne. In addition to ascertaining for associated comorbidities, management should also include regular follow-up visits and planned transition to adult care providers. Comprehensive knowledge regarding the pathogenesis of PCOS will enable earlier identification of girls with high propensity to develop PCOS. Timely implementation of individualized therapeutic interventions will improve overall management of PCOS during adolescence, prevent associated comorbidities, and improve quality of life.

Inferior fertility and higher concentrations of anti-Müllerian hormone in dairy cows with longer anogenital distance

Anogenital distance (AGD), which is an indicator of prenatal androgen exposure, has been reported to have high variability and negative association with fertility in dairy cows. Prenatal exposure to androgens could influence the development of primordial follicles and size of ovarian reserve, which is related to reproduction. However, the relationship between AGD and size of ovarian reserve has not been studied. Therefore, the present study was conducted to determine the association between AGD and circulating anti-Müllerian hormone (AMH), as an indirect marker of ovarian reserve, and to evaluate serum AMH concentration and reproductive performance in dairy cows with short and long AGD. Anogenital distance was measured 28 to 32 d postpartum, and based on the median of AGD, cows were divided into 2 subsets including short (n = 43) and long (n = 43) AGD groups. Afterward, serum AMH was evaluated on the day of estrus in cows that were estrus-synchronized. Furthermore, reproductive data of dairy cows during the previous lactation period were collected from the herd database. Concentrations of serum AMH tended to be positively associated with length of AGD, and there was a tendency for higher serum AMH concentrations in the long (634.89 ± 74.52 pg/mL) than short (451.39 ± 45.92 pg/mL) AGD group (0.05 <P ≤ 0.10). There was a tendency for more days to first service, lower first service conception rate, and higher proportion of repeat breeders in long (99.95 ± 5.34 d, 30.23% and 32.56%, respectively) than short (89.07 ± 4.97 d, 48.84% and 16.28%, respectively) AGD cows (0.05 <P ≤ 0.10). Services per conception did not differ between short (2.30 ± 0.27) and long (2.93 ± 0.29) AGD cows (P > 0.05). Calving to conception interval was prolonged in long (194.30 ± 17.12 d) than short (147.14 ± 13.11 d) AGD cows (P ≤ 0.05). In conclusion, the present study revealed elevated serum AMH concentrations and poor reproductive performance in cows with longer AGD compared with cows with shorter AGD.

Kisspeptin and Polycystic Ovary Syndrome

Although the pathogenesis of Polycystic Ovary Syndrome (PCOS) is still unclear, the disturbance of hypothalamic-pituitary-gonadal (HPG) axis is suspected to be the main culprit in the development of PCOS. Kisspeptin, a hypothalamic peptide encoded by the KISS1 gene, is widely reported as a key factor in the regulation of luteinizing hormone (LH)/ follicular-stimulating hormone (FSH) secretion, which may be potentially involved with the development of PCOS. Objective: The objective of this study is to summarize the existing knowledge in the literature in terms of the circulating kisspeptin concentration in PCOS women, kisspeptin and metabolic profiles in PCOS women and kisspeptin expression in PCOS animal models. Method: A systematic literature search was conducted using "Pubmed," "Embase," "Web of Science" for all English language articles published up to July 2018 with the terms "PCOS," "Stein-Leventhal Syndrome," "Polycystic ovary syndrome," "metastins" and "kisspeptin". Conclusion: Overall, kisspeptin levels are higher in the PCOS population, which supports the hypothesis that an over-active KISS1 system leads to enhanced HPG-axis activity, thereby causing irregular menstrual cycles and excessive androgen release in PCOS women.