Diabetes mellitus and insulin resistance in mothers, fathers, sisters, and brothers of women with polycystic ovary syndrome: a systematic review and meta-analysis

Whole Exome Sequencing Reveals Rare Variants in Genes Associated with Metabolic Disorders in Women with PCOS

Background

Polycystic ovary syndrome (PCOS) is a complex genetic trait, the pathogenesis of which is governed by an interplay of genetic and epigenetic factors. However, the aetiology of PCOS is not fully understood.

Aims

The objective of this study was to investigate the genetic causes of PCOS by identifying rare variants in genes implicated in its pathophysiology.

Settings and Design

This was a hospital-based observational study.

Materials and Methods

We used whole-exome sequencing for 52 PCOS women to identify the rare variants in genes related to PCOS pathogenesis. Subsequently, we analysed these variants using in silico prediction software to determine their functional effects. We then assessed the relationship between these variants and the clinical outcomes of the patients.

Statistical Analysis Used

Student's t-test and Fisher's exact test were used to compare clinical parameters and frequency differences amongst PCOS patients with and without variants.

Results

A total of four rare exonic variants in obesity- and hyperinsulinaemia-related genes including UCP1 (p.Thr227Ile), UCP2 (p.Arg88Cys), IRS1 (p.Ser892Gly) and GHRL (p.Leu72Met) were identified in eight patients. Significant differences were observed between the patients carrying variants and those without variants. PCOS patients with identified variants exhibited significantly higher average body mass index and fasting insulin levels of PCOS subjects with identified variants compared to those without variants (P < 0.05). Additionally, there were significant differences in the variant frequencies of four variants when compared to the population database (P < 0.05).

Conclusion

This study shows a prevalence of rare variants in obesity and hyperinsulinaemia-related genes in a cohort of PCOS women, thereby underscoring the impact of the identified rare variants on the development of obesity and associated metabolic derangements in PCOS women.

Impact of Lisinopril on Cardiometabolic Risk Factors in Sisters of Women With Polycystic Ovary Syndrome

Women with polycystic ovary syndrome (PCOS), the most common endocrinopathy in reproductive age, are characterized by increased cardiometabolic risk. Similar hormonal and metabolic changes were found in their siblings. The purpose of our study was to compare blood pressure-lowering and pleiotropic effects of lisinopril between sisters of women with PCOS and their unrelated peers. The study included two age-, body mass index-, and blood pressure-matched groups of women with grade 1 hypertension: 26 sisters of PCOS probands (Group 1) and 26 individuals without a family history of PCOS (Group 2), receiving 10-40 mg of lisinopril daily. Blood pressure, glucose homeostasis markers, plasma levels of lipids (androgens, estradiol, high-sensitivity C-reactive protein (hsCRP), homocysteine, fibrinogen, and uric acid), and urinary albumin-to-creatinine ratio (UACR) were measured before lisinopril treatment and 6 months later. At baseline, the study groups differed in insulin sensitivity, testosterone, free androgen index (FAI), hsCRP, homocysteine, and UACR. Blood pressure-lowering properties of lisinopril did not differ between the groups. The decrease in homocysteine and UACR, although observed in both groups, was stronger in Group 2 than in Group 1. Only in women without a family history of PCOS lisinopril improved insulin sensitivity and reduce hsCRP, fibrinogen, and uric acid. The remaining markers did not change throughout the study. Cardiometabolic effects of lisinopril correlated with testosterone, free androgen index, and changes in insulin sensitivity. The obtained results suggest that cardiometabolic effects of lisinopril may be slightly less pronounced in sisters of women with PCOS than in women without a family history of this disorder.

The Impact of Atorvastatin on Cardiometabolic Risk Factors in Sisters of Women with Polycystic Ovary Syndrome

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a frequent endocrinopathy in young women with significantly increased cardiometabolic risk. Siblings of women with this disorder are at increased risk of insulin resistance and androgen excess. The current study was aimed at investigating cardiometabolic effects of atorvastatin in sisters of women with PCOS.

METHODS

This prospective observational study compared two age-, body mass index-, blood pressure-, and plasma lipid-matched groups of women with hypercholesterolemia: sisters of PCOS probands (group A) and unrelated control subjects (group B), receiving atorvastatin (40 mg daily). Plasma lipids, glucose homeostasis markers, concentrations of sex hormones, high-sensitivity C-reactive protein (hsCRP), homocysteine, fibrinogen and uric acid, and the urinary albumin-to-creatinine ratio (UACR) were measured before entering the study and 6 months later.

RESULTS

Both groups differed in the degree of insulin resistance, testosterone, free androgen index (FAI), circulating levels of hsCRP and homocysteine, and UACR. There were no between-group differences in the impact of atorvastatin on plasma lipids. Despite reducing hsCRP and homocysteine in both groups of women, the effect on these biomarkers was stronger in group B than in group A. Only in group B, atorvastatin did reduce fibrinogen, uric acid, and UACR. Only in group A, atorvastatin did worsen insulin sensitivity and tended to reduce testosterone and FAI. The impact of atorvastatin on hsCRP, homocysteine, fibrinogen, uric acid, and UACR inversely correlated with testosterone and FAI.

CONCLUSION

The obtained results suggest that sisters of women with PCOS may benefit to a lesser degree from atorvastatin treatment than other women.

Effect Modification of LHCGR Gene Variant (rs2293275) on Clinico-Biochemical Profile, and Levels of Luteinizing Hormone in Polycystic Ovary Syndrome Patients

 Polycystic ovary syndrome (PCOS) is a common multifaceted endocrine disorder among reproductive-aged women. Deranged luteinizing hormone levels and associated downstream signaling cascade mediated by its receptor luteinizing hormone chorionic gonadotropin receptor (LHCGR) are pivotal in the etiopathogenesis of PCOS. Genetic variations in the LHCGR have been associated with PCOS risk. However, the results are mixed and inconclusive. We evaluated the association of the LHCGR rs2293275 polymorphic variant with PCOS risk and its association with clinico-biochemical features of PCOS. 120 confirmed PCOS cases and an equal number of age-matched controls were subjected to clinical, biochemical, and hormonal investigations. Genotyping for rs2293275 was performed using polymerase chain reaction-restriction fragment length polymorphism. Logistic regression models were used to calculate odds ratios (ORs) at 95% confidence intervals (95% CIs). In the current study, PCOS cases reported a lower number of menstrual cycles per year than respective controls. A significantly higher BMI, Ferriman Galway score, levels of serum testosterone, insulin, TSH, FSH, and fasting glucose were observed in cases than in controls (p < 0.01). Compared to GG carriers, we observed a higher risk of developing PCOS in the subjects who harbored GA (OR 10.4, p < 0.0001) or AA (OR 7.73, p = 0.02) genotype. The risk persisted in the dominant model (GA + AA) as well (OR 10.29, p = 0.01). On stratification, a higher risk of developing PCOS was observed in variant genotype carriers who had a family history of either type two diabetes mellitus (OR 117; p < 0.0001) or hirsutism (OR 79; p < 0.0001). We also found significantly elevated levels of serum LH levels in the subject harboring GA and AA genotypes when compared to GG carriers. In the present study, we report a significant association of the LHCGR rs2293275 variant with the PCOS risk.

Insulin resistance in polycystic ovary syndrome across various tissues: an updated review of pathogenesis, evaluation, and treatment

Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by chronic ovulation dysfunction and overabundance of androgens; it affects 6-20% of women of reproductive age. PCOS involves various pathophysiological factors, and affected women usually have significant insulin resistance (IR), which is a major cause of PCOS. IR and compensatory hyperinsulinaemia have differing pathogeneses in various tissues, and IR varies among different PCOS phenotypes. Genetic and epigenetic changes, hyperandrogenaemia, and obesity aggravate IR. Insulin sensitization drugs are a new treatment modality for PCOS. We searched PubMed, Google Scholar, Elsevier, and UpToDate databases in this review, and focused on the pathogenesis of IR in women with PCOS and the pathophysiology of IR in various tissues. In addition, the review provides a comprehensive overview of the current progress in the efficacy of insulin sensitization therapy in the management of PCOS, providing the latest evidence for the clinical treatment of women with PCOS and IR.

Up-regulation of miR-133a-3p promotes ovary insulin resistance on granulosa cells of obese PCOS patients via inhibiting PI3K/AKT signaling

Background

MicroRNAs are a type of non-coding single-stranded RNA, which is involved in the regulation of ovary insulin resistance (IR). This study aims to explore the underlying mechanisms of miR-133a-3p regulating ovary IR in obese polycystic ovary syndrome (PCOS).

Methods

Granulosa cells (GCs) were extracted from follicular fluids of PCOS patients (obese PCOS group and non-obese PCOS group) and healthy women (control group). The expression of miR-133a-3p in GCs was detected by qRT-PCR. The targets and pathways of miR-133a-3p were predicted by bioinformatics analyses. The protein levels of PI3K, p-AKT, GLUT4, p-GSK-3β, and p-FOXO1 were measured by Western blotting.

Results

MiR-133a-3p was highly expressed in GCs from PCOS patients, especially in obese PCOS patients. The protein levels of PI3K and p-AKT was downregulated in GCs from PCOS patients. There were 11 target genes of miR-133a-3p enriching in PI3K/AKT signaling pathway. miR-133a-3p mimic downregulated the expression of PI3K, p-AKT, and GLUT4, and upregulated the protein levels of p-GSK-3β and p-FOXO1. miR-133a-3p inhibitor presented the opposite effect of miR-133a-3p mimic.

Conclusion

MiR-133a-3p promotes ovary IR on GCs of obese PCOS patients via inhibiting PI3K/AKT signaling pathway. This study lays a foundation for further research on the mechanism of ovary IR in obese PCOS patients.

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

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

Identifying novel genetic loci associated with polycystic ovary syndrome based on its shared genetic architecture with type 2 diabetes

Genome-wide association studies (GWAS) have identified several common variants associated with polycystic ovary syndrome (PCOS). However, the etiology behind PCOS remains incomplete. Available evidence suggests a potential genetic correlation between PCOS and type 2 diabetes (T2D). The publicly available data may provide an opportunity to enhance the understanding of the PCOS etiology. Here, we quantified the polygenic overlap between PCOS and T2D using summary statistics of PCOS and T2D and then identified the novel genetic variants associated with PCOS behind this phenotypic association. A bivariate causal mixture model (MiXeR model) found a moderate genetic overlap between PCOS and T2D (Dice coefficient = 44.1% and after adjusting for body mass index, 32.1%). The conditional/conjunctional false discovery rate method identified 11 potential risk variants of PCOS conditional on associations with T2D, 9 of which were novel and 6 of which were jointly associated with two phenotypes. The functional annotation of these genetic variants supports a significant role for genes involved in lipid metabolism, immune response, and the insulin signaling pathway. An expression quantitative trait locus functionality analysis successfully repeated that 5 loci were significantly associated with the expression of candidate genes in many tissues, including the whole blood, subcutaneous adipose, adrenal gland, and cerebellum. We found that SCN2A gene is co-localized with PCOS in subcutaneous adipose using GWAS-eQTL co-localization analyses. A total of 11 candidate genes were differentially expressed in multiple tissues of the PCOS samples. These findings provide a new understanding of the shared genetic architecture between PCOS and T2D and the underlying molecular genetic mechanism of PCOS.

Mapping research trends of insulin resistance in polycystic ovary syndrome from 2017 to 2021: A bibliometric analysis

INTRODUCTION

To map publication trends and explore research hotspots of insulin resistance (IR) in polycystic ovary syndrome (PCOS) study.

METHODS

With the theme of "Polycystic ovary syndrome" AND "Insulin Resistance", the key data set of Science Core Literature Collection (WoSCC) web from 2017 to 2021 was extracted and bibliometric analysis was performed. Through VOSviewer v1.6.10 software, the research trend in this field is analyzed visually.

RESULTS

2080 literatures about IR in PCOS from 2017 to 2021 were downloaded. The following basic information was collected for each article: country, author, institution, journal, references. The key words are divided into six categories: (1) The interaction between insulin resistance and chronic inflammation; (2) The relationship between insulin resistance and metabolic syndrome and nonalcoholic fatty liver disease; (3) The interaction between insulin resistance and hyperandrogenemia; (4) The relationship between insulin resistance and dyslipidemia; (5) Metformin may regulate insulin resistance in the treatment of PCOS; (6) The study of serum biomarkers in PCOS patients with insulin resistance.

DISCUSSION

The six key words extracted can provide an in-depth perspective for the study of IR in PCOS, and provide valuable information to help researchers identify potential research directions, collaborators and cooperative institutions.

Correlation of markers of inflammation with hormonal, metabolic parameters, insulin resistance and adiposity indices in first-degree relatives of patient with polycystic ovary syndrome

Background:

Polycystic ovary syndrome (PCOS) is a state of chronic low-grade inflammation. Low-grade inflammation has been linked to the development of cardiovascular disease (CVD). There is evidence of clustering for metabolic syndrome, hypertension, dyslipidaemia in type 2 diabetes mellitus and insulin resistance (IR) in mothers, fathers, sisters and brothers of women with PCOS.

Aims:

The aim is to study the levels of inflammatory markers and IR in first-degree relatives of patients with PCOS and find any correlation with hormonal parameters, metabolic parameters and adiposity indices in them.

Settings and Design:

A total of 66 first-degree relatives of a patient with PCOS were included in this cross-sectional study.

Materials and Methods:

All participants underwent detailed clinical evaluation and biochemical investigations, including high-sensitivity C-reactive protein (hsCRP), interleukin 6 (IL-6), luteinising hormone (LH), follicle-stimulating hormone (FSH) and total testosterone (only in females). Homeostasis model assessment of IR (HOMA-IR), lipid accumulation product and visceral adiposity index were calculated using standard equations. Visceral adipose tissue thickness and subcutaneous adipose tissue thickness were assessed using ultrasonography.

Statistical Analysis Used:

Spearman's and Pearson's correlation coefficients were used to analyse the correlation between different non-parametric and parametric data, respectively. Multiple linear regression was used to correlate multiple dependent factors.

Results:

The mean hs-CRP level was 2.4 ± 1.1 mg/L, which is greater than the cut-off of 2 mg/L and hs-CRP >2 mg/L was found in 62% (n = 41) participants. The mean IL-6 (3.5 ± 1.1 pg/ml) and total white blood cell count (7244 ± 2190/mm³) were in the normal range. The mean HOMA-IR was 2.35 ± 0.76, which is elevated, considering HOMA IR >2 as a predictor of IR and metabolic syndrome. HOMA IR >2 was found in 64% (n = 42) of the participants. Inflammatory markers were significantly correlated with LH and HOMA IR, even after multiple linear regression was fitted for each marker individually.

Conclusion:

Apparently, healthy first-degree relatives of PCOS patients had evidence of chronic low-grade inflammation. The chronic inflammation in them correlated well with HOMA-IR and LH but was independent of body mass index. This low-grade inflammation may predispose the first-degree relatives of PCOS to CVD.

Reproductive Health in First-degree Relatives of Patients With Polycystic Ovary Syndrome: A Review and Meta-analysis

CONTEXT

Polycystic ovary syndrome (PCOS) is a highly heritable disease. Emerging evidence elucidated the elevated prevalence of reproductive abnormalities in first-degree relatives (FDRs) of patients with PCOS.

OBJECTIVE

To explore the reproductive health in FDRs of patients with PCOS.

METHODS

Ten databases were searched in December 2020 (PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Chinese Biological Medical Literature, Chinese National Knowledge Infrastructure, Chinese Journals Full-text Database, WanFang, and World Health Organization international clinical trials registry platform). This study included cohort, case-control, or cross-sectional studies. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement was followed. Dichotomous data from each of the eligible studies were combined by the Mantel-Haenszel model. Standard mean differences with 95% CIs were assessed. Heterogeneities were assessed using I2 statistics, and the quality of evidence was evaluated by a US Agency for Healthcare Research and Quality Evidence-based Practice Center program and Grading of Recommendations, Assessment, Development and Evaluation approach.

RESULTS

Thirty-eight studies were included. The prevalence of PCOS (0.22; 95% CI, 0.16 to 0.29), menstrual irregularities (0.28; 95% CI, 0.22 to 0.34, P < .01), and ovary morphological changes were elevated in female PCOS FDRs. Female FDRs also presented with increased levels of luteinizing hormone, total testosterone (standard mean difference, 0.53; 95% CI, 0.28 to 0.78, P < .01), unconjugated testosterone, free androgen index, dehydroepiandrosterone sulfate (DHEAS), and antimüllerian hormone levels. Subgroup analyses indicated that some of these changes begun in pubertal girls. Furthermore, fathers of PCOS patients had a higher risk of premature baldness. The DHEAS level was elevated in male FDRs.

CONCLUSION

The findings of this analysis suggested that FDRs of patients with PCOS suffered from reproductive endocrinological dysregulations. Thus, more attention should be focused on this population.

Androgen Excess Increases Food Intake in a Rat Polycystic Ovary Syndrome Model by Downregulating Hypothalamus Insulin and Leptin Signaling Pathways Preceding Weight Gain

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common reproductive and metabolic disorder characterized by high androgen levels. The aim of this study was to evaluate the effects of hyperandrogenism on the hypothalamus and subsequently on the food intake and obesity in females.

METHODS

A dihydroxy testosterone (DHT)-induced rat model was established to recapitulate the hyperandrogenism features of PCOS patients. Body weight and food intake of the rats were recorded. The food intake of DHT-induced rats was restricted by pair feeding to exclude possible effects of weight gain on the hypothalamus. The expression levels of relevant proteins and mRNAs in the hypothalamus and primary hypothalamic neurons exposed to DHT were analyzed by Western blotting and RT-PCR, respectively. The leptin levels in the serum and cerebrospinal fluid (CSF) were measured, and leptin was injected via the intracerebroventricular (ICV) route to test the leptin sensitivity of the hypothalamus.

RESULTS

The excessive prepuberty androgen levels in the DHT-induced rats markedly elevated food intake prior to weight gain. Consistent with this, the expression of neuropeptide Y and agouti-related peptide mRNAs was upregulated, which occurred prior to obesity and even with restricted food intake. In addition, the hypothalamic sensitivity to insulin and leptin was also impaired in the DHT-induced rats before obesity and with restricted food intake. DHT significantly reduced the leptin levels in the CSF, and ICV injection of leptin inhibited the DHT-induced increase in food intake.

CONCLUSIONS

Androgen excess increased food intake in rats and promoted obesity by downregulating insulin and leptin signaling in the hypothalamus, most likely by suppressing leptin levels in the CSF.

The Impact of Telmisartan on Cardiometabolic Risk Factors in Hypertensive Male Siblings of Women With Polycystic Ovary Syndrome

Brothers of women with polycystic ovary syndrome (PCOS) were found to be at increased risk for cardiometabolic disorders. This risk may be exacerbated by concurrent poorly controlled hypertension. Angiotensin II receptor blockers are the most frequently used antihypertensive drugs. The aim of the present study was to compare blood pressure-lowering and pleiotropic effects of telmisartan between male siblings of PCOS probands and unrelated men. The study included 2 age-, blood pressure-, and mass index-matched groups of men with grade 1 hypertension: 24 brothers of women with PCOS (group A) and 26 brothers of healthy women (group B). All subjects were treated with telmisartan (80 mg daily). Blood pressure, glucose homeostasis markers, and plasma lipids, as well as plasma levels of total testosterone, bioavailable testosterone, androstenedione, uric acid, high-sensitivity C-reactive protein (hsCRP), homocysteine, fibrinogen, and 25-hydroxyvitamin D were measured before and after 12 weeks of therapy. At entry, there were between-group differences in the degree of insulin resistance, plasma levels of high-density lipoprotein-cholesterol, triglycerides, calculated bioavailable testosterone, androstenedione, hsCRP, and 25-hydroxyvitamin D. Although telmisartan reduced blood pressure in both study groups, this effect was stronger in group B. Irrespective of the study group, the drug improved insulin sensitivity and reduced circulating levels of uric acid and homocysteine, but these effects were more pronounced in group B than group A. Only in group B, telmisartan decreased hsCRP and fibrinogen, as well as increased 25-hydroxyvitamin D. The obtained results suggest that hypertensive male relatives of PCOS probands may gain less benefit from telmisartan treatment than unrelated hypertensive men.

Endocrinological and metabolic characteristics in patients who are non-obese and have polycystic ovary syndrome and different types of a family history of type 2 diabetes mellitus

Objective

We aimed to investigate whether patients with polycystic ovary syndrome (PCOS) and a family history (FH) of type 2 diabetes mellitus (T2DM) are at increased risk of endocrinological and metabolic abnormalities, and whether this risk differs between first-degree and second-degree relatives, and between maternal and paternal transmission.

Methods

A total of 680 patients with PCOS were enrolled in this retrospective, single-center study. Endocrine and glycolipid metabolism parameters were compared.

Results

The free androgen index (FAI), and levels of fasting blood glucose (FBG), fasting insulin (FINS), homeostatic model assessment-insulin resistance (HOMA-IR), total cholesterol (TC), and low-density lipoprotein cholesterol were significantly higher, whereas sex hormone binding globulin (SHBG) levels were significantly lower in patients with PCOS and a FH of T2DM. In patients with PCOS with a FH of T2DM in first-degree relatives, age and levels of FBG, FINS, and HOMA-IR were significantly higher than those who had a FH of T2DM in second-degree relatives. A maternal history of T2DM was associated with a higher body mass index, FAI, and TG levels, and lower SHBG levels.

Conclusions

Patients with PCOS and a FH of T2DM have more severe hyperandrogenism and metabolic disorders, especially in those with maternal transmission.

Cardiometabolic Risk Factors in Rosuvastatin-Treated Men with Mixed Dyslipidemia and Early-Onset Androgenic Alopecia

Men with early-onset androgenetic alopecia are characterized by hormonal profiles similar to those observed in women with polycystic ovary syndrome. The purpose of this research was to investigate levels of cardiometabolic risk factors in 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA)-treated men with early-onset androgenic alopecia. We studied two matched rosuvastatin-treated groups of men with mixed dyslipidemia: subjects with early-onset androgenic alopecia (group A) and subjects with normal hair growth (group B). Plasma lipids, glucose homeostasis markers, and levels of sex hormones, uric acid, hsCRP, homocysteine, fibrinogen, and 25-hydroxyvitamin D were measured before entering the study and six months later. Both groups differed in insulin sensitivity and levels of calculated bioavailable testosterone, dehydroepiandrosterone-sulfate, uric acid, hsCRP, fibrinogen, and 25-hydroxyvitamin D. Though observed in both study groups, treatment-induced reductions in total cholesterol, LDL cholesterol, hsCRP, and fibrinogen were more pronounced in group B than group A. Moreover, only in group A did rosuvastatin deteriorate insulin sensitivity, and only in group B did the drug affect uric acid, homocysteine, and 25-hydroxyvitamin D. The impact of rosuvastatin on cardiometabolic risk factors correlated with insulin sensitivity, calculated bioavailable testosterone, and dehydroepiandrosterone-sulfate. The obtained results suggest that men with early-onset androgenic alopecia may benefit to a lesser degree from rosuvastatin treatment than their peers.

Association between melatonin receptor gene polymorphisms and polycystic ovarian syndrome: a systematic review and meta-analysis

BACKGROUND

Polycystic ovarian syndrome (PCOS) is a kind of common gynecological endocrine disorder. And the mutations of melatonin receptor (MTNR) genes are related to the occurrence of PCOS. But previous researches have shown opposite results. So, the object of our systematic review and meta-analysis is to investigate the relationship between MTNR 1A/B polymorphisms and PCOS.

METHODS

PubMed, Embase, Ovid, the Cochrane Library, Web of Science and three Chinese databases (VIP, CNKI and Wanfang) were used to retrieve eligible articles published between January 1980 and February 2020. And we used the odds ratio (OR) and its 95% confidence interval (CI) to investigate the strength of the association by six genetic models, allelic, codominant (homozygous and heterozygous), dominant, recessive and superdominant models. Review Manager 5.3, IBM SPSS statistics 25 and Stata MP 16.0 software were used to do this meta-analysis.

RESULTS

Our meta-analysis involved 2553 PCOS patients and 3152 controls, for two single nucleotide polymorphisms (rs10830963 C> G in MTNR1B and rs2119882 T> C in MTNR1A) and significant associations were found in some genetic models of these single nucleotide polymorphisms (SNPs). For rs10830963, strongly significant was found in the heterozygote model (GC vs. CC, P=0.02). Additionally, a slight trend was detected in the allelic (G vs. C), homozygote (GG vs. CC) and dominant (GG+GC vs. CC) model of rs10830963 (P=0.05). And after further sensitivity analysis, a study with high heterogeneity was removed. In the allelic (P=0.000), homozygote (P=0.001), dominant (P=0.000) and recessive (GG vs. GC+CC, P=0.001) model, strong associations between rs10830963 and PCOS were found. Moreover, for rs2119882, five genetic models, allelic (C vs. T, P=0.000), codominant (the homozygote (CC vs. TT, P=0.000) and heterozygote model (CT vs. TT, P=0.02), dominant (CC + CT vs. TT, P=0.03) and recessive model (CC vs. CT + TT, P=0.000) showed significant statistical associations with PCOS.

CONCLUSION

MTNR1B rs10830963 and MTNR1B rs2119882 polymorphisms are associated with PCOS risk. However, the above conclusions still require being confirmed by much larger multi-ethnic studies.

Insulin resistance and PCOS: chicken or egg?

PCOS is a common and heterogeneous endocrine disorder in women of reproductive age, frequently associated with metabolic abnormalities. It was estimated that about 75% of these subjects have an impairment of insulin action, as measured by gold standard methods. While the relationship between insulin resistance and PCOS is consistently shown by a number of studies, the mechanisms underlying its primary origin still remains an unsolved issue. Insulin resistance and the associated hyperinsulinemia can induce both the endocrine and reproductive traits of PCOS. However, androgen excess, in turn, can impair insulin action, directly and/or through several changes occurring in different tissues. Body fat excess, which is another common feature in these women, can contribute to worsening the whole picture. Nevertheless, insulin resistance may also be found in many normal-weight individuals. Endocrine and metabolic abnormalities can develop in different moments, and probably there is fetal programming of these alterations. However, a number of vicious circles, with bidirectional relationships between androgen excess and insulin resistance, and with the contribution of several other factors, make it extremely difficult to understand where this process really originates. This review summarizes available evidence on this topic, in order to better understand the complex relationships linking hyperandrogenism and impaired insulin action in women with PCOS.

Epigenetic Marks in Polycystic Ovary Syndrome

Polycystic Ovary Syndrome (PCOS) is a common endocrine and metabolic disorder that affects women in their reproductive age. Recent studies have shown that genes have an important role in the etiology of PCOS. However, the precise way in which these genes are transcriptionally and post-transcriptionally regulated is poorly understood. The aim of the present review is to provide updated information on miRNAs and DNA methylation as epigenetic marks of PCOS. The data presented here allow concluding that both microRNAs and DNA methylation can be considered as possible useful biomarkers when choosing the treatment for a specific PCOS phenotype and thus represent two important tools for the diagnosis and treatment of PCOS patients.

Mechanisms of intergenerational transmission of polycystic ovary syndrome

Developmental origins of adult disease (DoHAD) refers to critical gestational ages during human fetal development and beyond when the endocrine metabolic status of the mother can permanently program the physiology and/or morphology of the fetus, modifying its susceptibility to disease after birth. The aim of this review is to address how DoHAD plays an important role in the phenotypic expression of polycystic ovary syndrome (PCOS), the most common endocrinopathy of women characterized by hyperandrogenism, oligo-anovulation and polycystic ovarian morphology. Clinical studies of PCOS women are integrated with findings from relevant animal models to show how intergenerational transmission of these central components of PCOS are programmed through an altered maternal endocrine-metabolic environment that adversely affects the female fetus and long-term offspring health. Prenatal testosterone treatment in monkeys and sheep have been particularly crucial in our understanding of developmental programming of PCOS because organ system differentiation in these species, as in humans, occurs during fetal life. These animal models, along with altricial rodents, produce permanent PCOS-like phenotypes variably characterized by LH hypersecretion from reduced steroid-negative feedback, hyperandrogenism, ovulatory dysfunction, increased adiposity, impaired glucose-insulin homeostasis and other metabolic abnormalities. The review concludes that DoHAD underlies the phenotypic expression of PCOS through an altered maternal endocrine-metabolic environment that can induce epigenetic modifications of fetal genetic susceptibility to PCOS after birth. It calls for improved maternal endocrine-metabolic health of PCOS women to lower their risks of pregnancy-related complications and to potentially reduce intergenerational susceptibility to PCOS and its metabolic derangements in offspring.

Current concepts of polycystic ovary syndrome pathogenesis

PURPOSE OF REVIEW

This review provides a model for understanding polycystic ovary syndrome (PCOS) pathophysiology and updates the evidence on which it is based. Then, it highlights complimentary molecular genetic and epigenetic advances in understanding PCOS cause.

RECENT FINDINGS

Important studies into PCOS cause built on the 2014 discovery of a novel regulatory protein variant that underlies the typical PCOS steroidogenic abnormalities: DENND1A.V2 (differentially expressed in normal and neoplastic development, isoform 1A, variant 2). Over 30 DENND1A gene variants have been found, the vast majority upstream of the coding sequence and potentially regulatory. These variants are individually uncommon but collectively plausibly cause 50% of PCOS. Anti-Müllerian hormone (AMH)/AMH receptor variants with decreased function possibly cause 6.7% of PCOS. DENNND1A was recently reported to belong to a signaling network that upregulates luteinizing hormone receptor expression and insulin mitogenic signaling. Prenatal androgen administration has proven to be a potent epigenetic regulator that causes transgenerational epigenomic changes in a mouse PCOS model with similarities to those in human PCOS and PCOS daughters.

SUMMARY

In addition to finding how gene variants contribute to PCOS pathogenesis, better understanding of androgen epigenetic mechanisms of action in diverse tissues can be expected to expand our understanding of PCOS pathogenesis.

Anogenital distance in children born of mothers with polycystic ovary syndrome: the Odense Child Cohort

STUDY QUESTION

Are higher testosterone levels during pregnancy in women with polycystic ovary syndrome (PCOS) associated with longer offspring anogenital distance (AGD)?

SUMMARY ANSWER

AGD was similar in 3-month-old children born of mothers with PCOS compared to controls.

WHAT IS KNOWN ALREADY

AGD is considered a marker of prenatal androgenization.

STUDY DESIGN, SIZE, DURATION

Maternal testosterone levels were measured by mass spectrometry at Gestational Week 28 in 1127 women. Maternal diagnosis of PCOS before pregnancy was defined according to Rotterdam criteria. Offspring measures included AGD from anus to posterior fourchette (AGDaf) and clitoris (AGDac) in girls and to scrotum (AGDas) and penis (AGDap) and penile width in boys and body composition (weight and BMI SD scores) at age 3 months.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The study was part of the prospective study, Odense Child Cohort (OCC), and included mothers with PCOS (n = 139) and controls (n = 1422). The control population included women with regular menstrual cycles (<35 days) before conception and no signs of androgen excess (hirsutism and/or acne).

MAIN RESULTS AND THE ROLE OF CHANCE

AGD measures were comparable in offspring of women with PCOS compared to controls (all P > 0.2) despite significantly higher maternal levels of total testosterone (mean: 2.4 versus 2.0 nmol/l) and free testosterone (mean: 0.005 versus 0.004 nmol/l) in women with PCOS versus controls (both P < 0.001). In women with PCOS, maternal testosterone was an independent positive predictor of offspring AGDas and AGDap in boys. Maternal testosterone levels did not predict AGD in girls born of mothers with PCOS or in boys or girls born of women in the control group.

LIMITATIONS, REASONS FOR CAUTION

The diagnosis of PCOS was based on retrospective information and questionnaires during pregnancy. Women participating in OCC were more ethnically homogenous, leaner, more educated and less likely to smoke compared to the background population. Our study findings, therefore, need to be reproduced in prospective study cohorts with PCOS, in more obese study populations and in women of other ethnicities.

WIDER IMPLICATIONS OF THE FINDINGS

Our finding of the same AGD in girls born of mothers with PCOS compared to controls expands previous results of studies reporting longer AGD in adult women with PCOS. Our results suggest that longer AGD in adult women with PCOS could be the result of increased testosterone levels in puberty, perhaps in combination with weight gain.

STUDY FUNDING/COMPETING INTEREST(S)

Financial grants for the study were provided by the Danish Foundation for Scientific Innovation and Technology (09-067180), Ronald McDonald Children Foundation, Odense University Hospital, the Region of Southern Denmark, the Municipality of Odense, the Mental Health Service of the Region of Southern Denmark, The Danish Council for Strategic Research, Program Commission on Health, Food and Welfare (2101-08-0058), Odense Patient data Explorative Network, Novo Nordisk Foundation (grant no. NNF15OC00017734), the Danish Council for Independent Research and the Foundation for research collaboration between Rigshospitalet and Odense University Hospital and the Health Foundation (Helsefonden). There is no conflict of interest of any author that could be perceived as prejudicing the impartiality of the research reported.

Cardiovascular disease risk in the siblings of women with polycystic ovary syndrome

STUDY QUESTION

Do the siblings of Asian Indian women with polycystic ovary syndrome (PCOS) manifest increased cardiovascular disease (CVD) risk by carotid intima-media thickness (CIMT) and brachial artery flow-mediated dilatation (FMD)?

SUMMARY ANSWER

Siblings had functional endothelial dysfunction (FMD was reduced) when compared to age and BMI-matched controls while sisters but not brothers had structural endothelial dysfunction (CIMT was increased).

WHAT IS KNOWN ALREADY

Siblings of women with PCOS have increased metabolic risk but it varies with ethnicity. Among Asian Indians the only previous study has shown reduced FMD in brothers.

STUDY DESIGN, SIZE, DURATION

This study was a tertiary care hospital-based cross-sectional case control study in the outpatient department of the endocrine clinic over 18 months. In total, 41 brothers and 35 sisters of women with PCOS (diagnosed by 2003 Rotterdam criteria) were recruited.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Age (±2 years), sex and BMI- (±1 kg/m2) matched controls were selected. Cases and controls underwent clinical and biochemical investigations. Cardiologists performed doppler ultrasonogram to determine CIMT and FMD in a blinded fashion.

MAIN RESULTS AND THE ROLE OF CHANCE

FMD was decreased in brothers [median 12.3% interquartile range (5.1, 19) versus 18.4% (12.6, 21.5), P = 0.002] and in sisters [10.8% (5.8, 17.2) versus 14.7% (11.4, 18.2), P = 0.027] when compared to controls. CIMT was higher in sisters [median 0.4 mm (0.35, 0.5) versus 0.3 mm (0.3, 0.4), P= 0.002] when compared to controls but not in brothers. Metabolic syndrome was more common in brothers (27% versus 5% in controls, P = 0.007) even after matching for age and BMI. Insulin resistance (homeostatic model assessment for insulin resistance and acanthosis) was higher in brothers as compared to controls. Dehydroepiandrosterone sulphate was significantly elevated in brothers.

LIMITATIONS, REASONS FOR CAUTION

There may have been referral bias of patients with PCOS in a tertiary care institute, and the radiological assessment was performed by two cardiologists serially on different time frames over the study duration. Power was only 50% in CIMT for brothers.

WIDER IMPLICATIONS OF THE FINDINGS

Siblings of women with PCOS had higher CVD risk over and above the already pre-existing higher metabolic risk associated with Asian Indian ethnicity and therefore the siblings require vigilant management. Endothelial dysfunction and insulin resistance seems to be a heritable trait of PCOS independent of obesity, which if confirmed in other ethnicities would have important implications.

STUDY FUNDING/COMPETING INTEREST(S)

Funded by Intramural Research Grant (PGI/DIR/RC/943/2013) from the Sanjay Gandhi Postgraduate Institute of Medical Sciences. No competing interests.

The impact of atorvastatin on cardiometabolic risk factors in brothers of women with polycystic ovary syndrome

Background

Women with polycystic ovary syndrome (PCOS) are characterized by increased cardiometabolic risk. The aim of the current study was to compare the impact of atorvastatin on plasma levels of cardiometabolic risk factors between men whose sisters had either PCOS or were unaffected.

Methods

The study population consisted of two age-, fat-free mass index-, blood pressure- and plasma lipid-matched groups of men with elevated total and LDL cholesterol levels: 20 brothers of PCOS probands (group 1) and 20 brothers of healthy women (group 2). Both groups were then treated with atorvastatin (40 mg daily) for the following 6 months. At the beginning and at the end of the study, we assessed plasma lipid levels, glucose homeostasis markers and levels of dehydroepiandrosterone sulfate, testosterone, bioavailable testosterone, uric acid, high-sensitivity C-reactive protein (hsCRP), homocysteine, fibrinogen and 25-hydroxyvitamin D.

Results

At the beginning of the study, both treatment arms differed in the degree of insulin resistance, calculated bioavailable testosterone, as well as in plasma levels of dehydroepiandrosterone sulfate, uric acid, hsCRP and 25-hydroxyvitamin D. Although atorvastatin reduced total and LDL cholesterol levels, this effect was stronger in group 2 than group 1. In group 2, atorvastatin exerted also a more potent impact on hsCRP, fibrinogen and homocysteine. An unfavorable impact on insulin sensitivity was observed only in group 1; while, statistically significant changes in uric acid and 25-hydroxyvitamin D levels were found only in group 2.

Conclusion

The obtained results suggest that cardiometabolic effects of atorvastatin are less pronounced in male siblings of PCOS probands than in brothers of unaffected women.

PCOS-GWAS Susceptibility Variants in THADA, INSR, TOX3, and DENND1A Are Associated With Metabolic Syndrome or Insulin Resistance in Women With PCOS

Polycystic ovary syndrome is characterized by reproductive and metabolic disturbances throughout the female lifespan. Therefore, this study aimed to determine whether genome-wide association studies (GWAS)-identified risk variants for PCOS could confer risk of metabolic syndrome (MS) or insulin resistance (IR). Fifteen independent SNPs mapping to 11 GWAS loci genotyped in a total of 2,082 Han Chinese women independent of previous GWAS and phenotype-genotype correlations were assessed. The CC group for rs12478601 in THADA was associated with decreased rate of MS after adjustment for age (23.2 vs. 27%, P = 0.042, OR = 0.81). Using a dominant model, the GG+AG group for rs2059807 in INSR was associated with increased risk of MS after adjustment for age (26.8 vs. 22.5%, P = 0.023, OR = 1.27). The GG + GT group for rs4784165 in TOX3 was found to be associated with an increased rate of IR after adjustment for age and BMI(53.3 vs. 48.5%, P = 0.027, OR = 1.27). The GG+AG group for rs2479106 in DENND1A was associated with a decreased rate of IR (48.3 vs. 53.6%, adjusted P = 0.039, OR = 0.80). After exclusion of PCOS cases with a family history of diabetes, hypertension, or dyslipidemia, the phenotype-genotype correlations between the genes INSR and TOX3 and MS or IR were still significant (P < 0.05). Three SNPs (rs13429458 in THADA, rs10818854 in DENND1A, and rs2059807 in INSR) were significantly associated with IR; however, their association was not significant after adjustment for age and BMI. This genotype-phenotype study thus provides clues that THADA, INSR, TOX3, and DENND1A play a role in PCOS possibly through a metabolic disorder-related pathway.

Curtailing PCOS

Polycystic ovary syndrome (PCOS), characterized by hormonal imbalance and ovarian dysfunction, often starts during adolescence. Inconsistent diagnostic criteria, variable provider knowledge, and lack of consensus pose specific challenges for the care of women with PCOS. These factors encourage inaccurate diagnosis with both under and overdiagnosis. This unfavorable diagnostic experience exasperates affected women and limits timely opportunities for intervention to minimize associated comorbidities, especially during the transition from pediatric to adult care. Recognition of these issues in the care of adolescents and women with PCOS inspired the development of the International Evidence-Based PCOS Guidelines, which emphasize the prevention, screening, and treatment of PCOS across the reproductive lifespan. The Guidelines and accompanying meta-analyses focus on three major categories of associated comorbidities: (1) reproductive; (2) metabolic; and (3) psychological. With the exception of infertility, this article considers common manifestations and comorbidities associated with PCOS throughout the lifecycle. Healthy lifestyle interventions with prevention of excess weight gain comprise the primary intervention for all comorbidities. Hence, early identification of girls "at risk" for PCOS and those with PCOS is a priority. Extensive guidelines for provider and patient education aim to decrease the medical, psychosocial, and economic burdens attributable to PCOS and its associated comorbidities.

Follicle Stimulating Hormone Receptor (FSHR) Polymorphisms and Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the commonest endocrine abnormality in women of reproductive age typically presenting with chronic oligo- or anovulation, clinical, or biochemical hyperandrogenism and polycystic ovarian morphology (PCOM). Restoring mono-ovulation is the ultimate goal of ovulation induction and most women do respond to ovulation inducing agents causing their Follicle-stimulating hormone (FSH) levels to rise. Familial clustering and the results from twin studies strongly support an underlying genetic basis for PCOS. Recent Genome wide association studies (GWAS) have identified several genetic variants being genome wide significantly associated with PCOS. Amongst those are variants in or near the Luteinizing hormone (LH) and FSH receptor genes as well as a variant in the FSH-β gene. The aim of this review is to summarize the available evidence as to whether single nucleotide polymorphisms are able to modify the PCOS phenotype or whether they constitute a risk factor for the syndrome. Data on the role of FSHR polymorphisms in PCOS are conflicting. It seems that in large Chinese studies FSHR polymorphisms are not associated with either PCOS risk or with PCOS treatment outcome. However, in large scale studies in Caucasians these polymorphisms seem to influence the risk of having PCOS. Moreover, these studies also showed that some polymorphisms might affect some clinical features of PCOS as well as treatment outcome. Although most research has focussed on the role of FSHR polymorphisms there seems to be also some evidence showing that single nucleotide polymorphisms (SNPs) in the LHCG-Receptor as well as those in FSH-β gene might also alter the phenotype of PCOS. In conclusion most studies confirm that FSHR polymorphisms do alter the phenotype of PCOS in that they either alter the response to exogenous FSH or hat they increase the risk of having PCOS.