Polycystic Ovary Syndrome: the Epigenetics Behind the Disease

Resistance and aerobic training increases genome-wide DNA methylation in women with polycystic ovary syndrome

Physical activity is a first-line treatment for polycystic ovary syndrome (PCOS). Resistance or aerobic exercise improves metabolic complications, reproductive outcomes, and quality of life in PCOS. DNA methylation reprogramming during exercise may be the major modifier behind these changes. We sought to evaluate genome-wide DNA methylation changes after supervised resistance and aerobic exercise in women with PCOS. Exercises were performed in 56 women with PCOS (resistance, n = 30; aerobic, n = 26), for 16 weeks (wks), three times per week, in 50-minute to one-hour sessions. Anthropometric indices and hormonal and metabolic parameters were measured before and after training. Genome-wide leukocyte DNA methylation was analysed by Infinium Human MethylationEPIC 850K BeadChip microarrays (Illumina). Both resistance and aerobic exercise improved anthropometric indices, metabolic dysfunction, and hyperandrogenism in PCOS after the training programme, but no differences were observed between the two exercises. Resistance and aerobic exercise increased genome-wide DNA methylation, although resistance changed every category in the CpG island context (islands, shores, shelve, and open sea), whereas aerobic exercise altered CpG shores and the open sea. Using a stringent FDR (>40), 6 significantly differentially methylated regions (DMRs) were observed in the resistance exercise cohort and 14 DRMs in the aerobic cohort, all of which were hypermethylated. The increase in genome-wide DNA methylation may be related to the metabolic and hormonal changes observed in PCOS after resistance and aerobic exercise. Since the mammalian genome is hypermethylated globally to prevent genomic instability and ageing, resistance and aerobic exercise may promote health and longevity through environmentally induced epigenetic changes.

The effect of ellagic acid on sex hormones and miRNA-21 expression in rats with polycystic ovary syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women of reproductive age. It is characterized by irregular menstrual cycles, hyperandrogenism, and polycystic ovaries. The syndrome's etiology is multifactorial, involving genetic, hormonal, metabolic, and environmental factors. Given its diverse effects, managing PCOS requires a comprehensive approach.

METHODS

This study employed a Sprague-Dawley rat model to investigate the effects of ellagic acid on polycystic ovary syndrome (PCOS). Forty adult female rats were randomly divided into four groups: a control group, a healthy group receiving ellagic acid (200 mg/kg), a PCOS group, and an ellagic acid + PCOS group. PCOS was induced in the relevant groups through subcutaneous injection of estradiol valerate (2 mg/kg), and ellagic acid was administered via subcutaneous injections for 14 days. Blood samples were collected for hormone analysis using the ELISA method, and ovarian tissues were processed for histological examination.

RESULT

Ellagic acid treatment showed reduced LH levels and restoration of follicular development, particularly primordial and graafian follicles, along with modulation of miRNA-21 expression. Moreover, ellagic acid exhibited positive effects on ovarian morphology, including decreased theca layer thickness, increased oocyte diameter, and improvements in antral and preovulatory follicles. This suggests ellagic acid's potential in addressing follicular development and oocyte quality in PCOS.

CONCLUSIONS

These findings suggest ellagic acid as a potential complementary approach in PCOS management. While the study is promising, further research, including clinical trials, is required to elucidate ellagic acid's mechanisms and clinical efficacy in human PCOS subjects.

Obesity contributes to telomere shortening in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a multifactorial disorder and obesity occurs in 38% to 88% of these women. Although hyperandrogenism may contribute to telomere lengthening, increased body mass index (BMI) is associated with telomere erosion. We sought to compare leukocyte telomere length (LTL) in PCOS women with normal, overweight, and obese BMI. We evaluated the relationship between LTL and clinical variables of PCOS and inflammatory biomarkers independent of BMI. A total of 348 women (243 PCOS and 105 non-PCOS) were evaluated for anthropometric measures, total testosterone, androstenedione, estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), free androgen index (FAI), fasting insulin and glycemia, lipid profile, homocysteine, C-reactive protein (CRP) and homeostatic model of insulin resistance (HOMA-IR). LTL was measured by qPCR. The PCOS group presented higher weight, waist circumference, BMI, testosterone, LH, fasting insulin, FAI, and HOMA-IR, and lower E2, SHBG, and fasting glycemia measures compared with the non-PCOS. When stratified by BMI, LTL was increased in all subgroups in PCOS compared to non-PCOS. However, in the PCOS group, LTL was lower in overweight (P = 0.0187) and obese (P = 0.0018) compared to normal-weight women. The generalized linear model showed that BMI, androstenedione, homocysteine, and CRP were associated with telomere biology. Women with PCOS had longer LTL, however, overweight or obesity progressively contributes to telomere shortening and may affect reproductive outcomes of PCOS, while androstenedione may increase LTL.

Optimizing Dietary Habits in Adolescents with Polycystic Ovary Syndrome: Personalized Mediterranean Diet Intervention via Clinical Decision Support System-A Randomized Controlled Trial

The hypothesis of this randomized controlled trial was that a clinical decision support system (CDSS) would increase adherence to the Mediterranean diet (MD) among adolescent females with polycystic ovary syndrome (PCOS). The objective was to assess the impact of personalized MD plans delivered via a CDSS on nutritional status and psychological well-being. Forty adolescent females (15-17 years) with PCOS were randomly assigned to the MD group (n = 20) or the Control group (n = 20). The MD group received personalized MD plans every 15 days via a CDSS, while the Control group received general nutritional advice. Assessments were conducted at baseline and after 3 months. Results showed significantly increased MD adherence in the MD group compared to the Control group (p < 0.001). The MD group exhibited lower intakes of energy, total fat, saturated fat, and cholesterol, and higher intakes of monounsaturated fat and fiber (p < 0.05). Serum calcium and vitamin D status (p < 0.05), as well as anxiety (p < 0.05) were improved. In conclusion, tailored dietary interventions based on MD principles, delivered via a CDSS, effectively manage PCOS in adolescent females. These findings highlight the potential benefits of using technology to promote dietary adherence and improve health outcomes in this population. ClinicalTrials.gov registry: NCT06380010.

A randomized controlled trial comparing pioglitazone and metformin prior to in vitro fertilization in polycystic ovary syndrome - associated infertile women: impact on pregnancy rates

Background

Polycystic ovarian syndrome (PCOS) is one of the significant causes of infertility. Impaired glucose metabolism and insulin resistance add chiefly to the pathogenesis of PCOS. This study aimed to evaluate the efficacy of metformin and pioglitazone (insulin sensitizers) on the quality of the ovum and pregnancy rate in the IVF cycle.

Methods

In this randomized clinical trial study, 172 infertile women with PCO were enrolled and randomly assigned to receive either 15 mg pioglitazone (case group) or 1000 mg metformin (control group) twice a day for 6 weeks before IVF, and the pregnancy rate was compared across the groups. The number of ovum and embryos were also accessed and compared between the two groups.

Results

In the study, 172 patients participated. The mean age in the control and case groups was 32.09±3.9 years and 32.12±3.9 years, respectively, with no significant age difference. In both groups, the mean number of IVF eggs retrieved was 11.76±3.7 (control) and 11.86±3.7 (case), and the number of embryos formed was 7.43±2.8 (control) and 7.87±3.5 (case), with no significant disparities (P<0.05). Regarding positive pregnancies, 28 out of 86 (32.6%) occurred in the control group, while 42 out of 86 (48.8%) happened in the case group, demonstrating a significant difference (P=0.03).

Conclusions

According to the results obtained in this study, it may be concluded that pioglitazone is superior to metformin in IVF cycles in PCOS-associated infertile women leading to a higher pregnancy rate.

Traditional Chinese medicine formulae: A complementary method for the treatment of polycystic ovary syndrome

ETHNOPHARMACOLOGICAL RELEVANCE

Polycystic ovary syndrome (PCOS) is a prevalent female endocrine condition that significantly affects women of all age groups and is characterized by metabolic dysfunction. The efficacy of existing pharmaceutical interventions for the treatment of PCOS remains inadequate. With a rich history and cultural significance spanning thousands of years, Traditional Chinese Medicine (TCM) is extensively employed for treating a variety of ailments and can serve as a supplementary therapy for managing PCOS. Multiple clinical observations and laboratory tests have unequivocally demonstrated the substantial effectiveness and safety of TCM formulae in treating PCOS, and further investigations are currently in progress.

AIM OF THE STUDY

To summarize the TCM formulae commonly employed in the clinical management of PCOS, examine their therapeutic benefits, investigate their mechanism of action, active constituents, and establish the correlation between efficacy, mechanism of action, and active constituents.

MATERIALS AND METHODS

We conducted a comprehensive search on PubMed, Web of Science, and China national knowledge infrastructure (CNKI) using the following keywords: "Polycystic Ovary Syndrome", "Traditional Chinese Medicine Decoctions", "Traditional Chinese Medicine formulae", "Traditional Chinese Medicine", "Clinical Observation", "Mechanism", "Treatment", "Pharmacology", and various combinations of these terms. From January 1, 2006 until October 7, 2023, (inclusive).

RESULTS

This paper summarized the clinical effectiveness, mechanism of action, and active components of 8 TCM formulae for the treatment of PCOS. Our research indicates that TCM formulae can potentially treat PCOS by enhancing the levels of hyperandrogenism and other endocrine hormones, decreasing insulin resistance and hyperinsulinemia, and controlling chronic low-grade inflammation, among other modes of action. In addition, we found an association between epigenetics and TCM formulae for the treatment of PCOS.

CONCLUSION

TCM formulae have specific advantages in the treatment of Polycystic Ovary Syndrome (PCOS). They achieve therapeutic benefits by targeting several pathways and connections, attracting considerable interest and playing a vital role in the treatment of PCOS. TCM formulae can be used as an adjunctive therapy for the treatment of PCOS.

The Role of Sodium-Glucose Cotransporter-2 Inhibitors in the Treatment of Polycystic Ovary Syndrome: A Review

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-age women impacting their reproductive, mental, and metabolic health. Insulin resistance is a major driver of the pathophysiology of PCOS. There are several challenges with the management of this complex disorder including insufficient treatment options. Over the past 88 years, multiple hormonal and non-hormonal medications have been tried to treat the various components of this syndrome and there is no FDA (Food and Drug Administration)-approved medication specifically for PCOS yet. Sodium-glucose cotransporter-2 (SGLT-2) inhibitors have a unique mechanism of inhibiting the coupled reabsorption of sodium and glucose in renal proximal convoluted tubules. This review aims to examine the efficacy and side-effect profile of SGLT-2 inhibitors in patients with PCOS. In a limited number of studies, SGLT-2 inhibitors appear to be effective in improving menstrual frequency, reducing body weight and total fat mass, lowering total testosterone and DHEAS levels, and improving some glycemic indices in women with PCOS. SGLT2 inhibitors are generally well tolerated. With future research, it is possible that SGLT-2 inhibitors could become a key therapeutic option for PCOS.

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

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

Administration of adipose-derived mesenchymal stem cell conditioned medium improves ovarian function in polycystic ovary syndrome rats: involvement of epigenetic modifiers system

BACKGROUND

Polycystic ovary syndrome (PCOS) is a widespread heterogeneous disease that is in association with genetic, epigenetic, endocrine and environmental factors. Adipose-derived mesenchymal stem cell (ASC) and ASC-conditioned medium (ASC-CM) have shown promising abilities in tissue regeneration. In the present study, we aimed to investigate the effects of ASC and ASC-CM on epigenetic regulators, steroidal function and folliculogenesis in the letrozole-induced PCOS rats.

RESULTS

Based on the measurement of the oral glucose tolerance test and physical parameters including body weight, estrus cycle pattern as well as ovary dimensions, PCOS-induced rats in sham and control (CTRL) groups showed signs of reproductive dysfunctions such as lack of regular estrus cyclicity, metabolic disorders such as increased ovary dimension, body weight and blood glucose level alteration which were improved especially by ASC-CM administration.

Examination of newborn DNA methylation among women with polycystic ovary syndrome/hirsutism

Research suggests that polycystic ovary syndrome (PCOS) traits (e.g., hyperandrogenism) may create a suboptimal intrauterine environment and induce epigenetic modifications. Therefore, we assessed the associations of PCOS traits with neonatal DNA methylation (DNAm) using two independent cohorts. DNAm was measured in both cohorts using the Infinium MethylationEPIC array. Multivariable robust linear regression was used to determine associations of maternal PCOS exposure or preconception testosterone with methylation β-values at each CpG probe and corrected for multiple testing by false-discovery rate (FDR). In the birth cohort, 12% (102/849) had a PCOS diagnosis (8.1% PCOS without hirsutism; 3.9% PCOS with hirsutism). Infants exposed to maternal PCOS with hirsutism compared to no PCOS had differential DNAm at cg02372539 [β(SE): -0.080 (0.010); FDR p = 0.009], cg08471713 [β(SE):0.077 (0.014); FDR p = 0.016] and cg17897916 [β(SE):0.050 (0.009); FDR p = 0.009] with adjustment for maternal characteristics including pre-pregnancy BMI. PCOS with hirsutism was also associated with 8 differentially methylated regions (DMRs). PCOS without hirsutism was not associated with individual CpGs. In an independent preconception cohort, total testosterone concentrations were associated with 3 DMRs but not with individual CpGs, though the top quartile of testosterone compared to the lowest was marginally associated with increased DNAm at cg21472377 near an uncharacterized locus (FDR p = 0.09). Examination of these probes and DMRs indicate they may be under foetal genetic control. Overall, we found several associations among newborns exposed to PCOS, specifically when hirsutism was reported, and among newborns of women with relatively higher testosterone around conception.

Progress of the application clinical prediction model in polycystic ovary syndrome

Clinical prediction models play an important role in the field of medicine. These can help predict the probability of an individual suffering from disease, complications, and treatment outcomes by applying specific methodologies. Polycystic ovary syndrome (PCOS) is a common disease with a high incidence rate, huge heterogeneity, short- and long-term complications, and complex treatments. In this systematic review study, we reviewed the progress of clinical prediction models in PCOS patients, including diagnosis and prediction models for PCOS complications and treatment outcomes. We aimed to provide ideas for medical researchers and clues for the management of PCOS. In the future, models with poor accuracy can be greatly improved by adding well-known parameters and validations, which will further expand our understanding of PCOS in terms of precision medicine. By developing a series of predictive models, we can make the definition of PCOS more accurate, which can improve the diagnosis of PCOS and reduce the likelihood of false positives and false negatives. It will also help discover complications earlier and treatment outcomes being known earlier, which can result in better outcomes for women with PCOS.

The Effect of Metformin and Carbohydrate-Controlled Diet on DNA Methylation and Gene Expression in the Endometrium of Women with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is an endocrine disease associated with infertility and metabolic disorders in reproductive-aged women. In this study, we evaluated the expression of eight genes related to endometrial function and their DNA methylation levels in the endometrium of PCOS patients and women without the disease (control group). In addition, eight of the PCOS patients underwent intervention with metformin (1500 mg/day) and a carbohydrate-controlled diet (type and quantity) for three months. Clinical and metabolic parameters were determined, and RT-qPCR and MeDIP-qPCR were used to evaluate gene expression and DNA methylation levels, respectively. Decreased expression levels of HOXA10, GAB1, and SLC2A4 genes and increased DNA methylation levels of the HOXA10 promoter were found in the endometrium of PCOS patients compared to controls. After metformin and nutritional intervention, some metabolic and clinical variables improved in PCOS patients. This intervention was associated with increased expression of HOXA10, ESR1, GAB1, and SLC2A4 genes and reduced DNA methylation levels of the HOXA10 promoter in the endometrium of PCOS women. Our preliminary findings suggest that metformin and a carbohydrate-controlled diet improve endometrial function in PCOS patients, partly by modulating DNA methylation of the HOXA10 gene promoter and the expression of genes implicated in endometrial receptivity and insulin signaling.

Epigenetic regulation in premature ovarian failure: A literature review

Premature ovarian failure (POF), or premature ovarian insufficiency (POI), is a multifactorial and heterogeneous disease characterized by amenorrhea, decreased estrogen levels and increased female gonadotropin levels. The incidence of POF is increasing annually, and POF has become one of the main causes of infertility in women of childbearing age. The etiology and pathogenesis of POF are complex and have not yet been clearly elucidated. In addition to genetic factors, an increasing number of studies have revealed that epigenetic changes play an important role in the occurrence and development of POF. However, we found that very few papers have summarized epigenetic variations in POF, and a systematic analysis of this topic is therefore necessary. In this article, by reviewing and analyzing the most relevant literature in this research field, we expound on the relationship between DNA methylation, histone modification and non-coding RNA expression and the development of POF. We also analyzed how environmental factors affect POF through epigenetic modulation. Additionally, we discuss potential epigenetic biomarkers and epigenetic treatment targets for POF. We anticipate that our paper may provide new therapeutic clues for improving ovarian function and maintaining fertility in POF patients.

Modulation of the Inflammatory Response in Polycystic Ovary Syndrome (PCOS)-Searching for Epigenetic Factors

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. Despite its incidence, the syndrome is poorly understood and remains underdiagnosed, and female patients are diagnosed with a delay. The heterogenous nature of this complex disorder results from the combined occurrence of genetic, environmental, endocrine, and behavioral factors. Primary clinical manifestations of PCOS are derived from the excess of androgens (anovulation, polycystic ovary morphology, lack of or scanty, irregular menstrual periods, acne and hirsutism), whereas the secondary manifestations include multiple metabolic, cardiovascular, and psychological disorders. Dietary and lifestyle factors play important roles in the development and course of PCOS, which suggests strong epigenetic and environmental influences. Many studies have shown a strong association between PCOS and chronic, low-grade inflammation both in the ovarian tissue and throughout the body. In the vast majority of PCOS patients, elevated values of inflammatory markers or their gene markers have been reported. Development of the vicious cycle of the chronic inflammatory state in PCOS is additionally stimulated by hyperinsulinemia and obesity. Changes in DNA methylation, histone acetylation and noncoding RNA levels are presented in this review in the context of oxidative stress, reactive oxygen species, and inflammatory signaling in PCOS. Epigenetic modulation of androgenic activity in response to inflammatory signaling is also discussed.

MIR146A and ADIPOQ genetic variants are associated with birth weight in relation to gestational age: a cohort study

PURPOSE

To evaluate the genetic variants related to polycystic ovary syndrome (PCOS) and its metabolic complications in girls born small for gestational age (SGA).

DESIGN

Retrospective birth cohort study.

MATERIALS AND METHODS

We evaluated 66 women of reproductive age born at term (37-42 weeks of gestational age) according to the birth weight in relation to gestational age: 26 SGA and 40 AGA (Adequate for gestational age). Anthropometric and biochemical characteristics were measured, as well as the PCOS prevalence. We analyzed 48 single nucleotide polymorphisms (SNPs) previously associated with PCOS and its comorbidities using TaqMan Low-Density Array (TLDA). miRNet and STRING databases were used to predict target and disease networks.

RESULTS

Anthropometric and biochemical characteristics did not differ between the SGA and AGA groups, as well as insulin resistance and PCOS prevalence. Two SNPs were not in Hardy-Weinberg equilibrium, the rs2910164 (MIR146A C > G) and rs182052 (ADIPOQ G > A). The rs2910164 minor allele frequency (MAF) was increased in SGA (OR, 2.77; 95%; CI, 1.22-6.29), while the rs182052 was increased AGA (OR, 0.34; 95%; CI, 0.13 - 0.88). The alleles related to reduced miRNA-146a (C) and ADIPOQ (A) activity showed increased frequency in SGA. The mature miR-146a targets 319 genes, been the CXCR4, TMEM167A and IF144L common targets and contributes to PCOS. The ADIPOQ main protein interactions were ERP44, PPARGCIA and CDH13.

CONCLUSIONS

The miR-146a (rs2910164) and ADIPOQ (rs182052) allelic variants are related to birth weight in SGA and may predict health-related outcomes, such as PCOS and obesity risk.

Correlation of Serum Visfatin Level in Non-obese Women with Polycystic Ovary Syndrome and Matched Control

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrinopathy affecting reproductive-age women. Visfatin, an adipocytokine, and insulin resistance (IR) marker in diabetes since PCOS and diabetes share insulin resistance as an etiological factor, this study aimed to investigate visfatin as a predictive marker for IR and hyperandrogenemia in non-obese PCOS women and test its correlation to other parameters. A cross-sectional study conducted at the University Hospital recruited 140 women, divided into two groups. Group I (70/140, study group) was PCOS patients' diagnosis based on 2003 Rotterdam criteria and Group II (70/140, healthy controls). Both were aged, and body mass index (BMI) matched. After a detailed history and general examination, the clinical, demographic, biochemical, hormonal, and metabolic parameters were taken for comparison's sake. PCOS patients were subdivided according to the clinical or hormonal evidence of hyperandrogenemia into two groups: those with hyperandrogenemia and those without. Higher serum visfatin was estimated in the PCOS group (4.4 ± 1.7) versus healthy controls (3.1 ± 0.7) ng/mL, P < 0.0001. Significantly higher visfatin was confirmed in hyperandrogenic PCOS versus non-hyperandrogenic PCOS women (5.69 ± 1.1 vs. 2.76 ± 0.51 ng/mL). A strong correlation was found between visfatin versus hemoglobin A1c and free androgen index (FAI); r = 0.784 and 0.624, respectively. BMI and free testosterone scored a modest correlation. BMI centiles' correlation with serum visfatin revealed no significant effect on serum visfatin, P = 0.62. The ROC calculated visfatin cut-off value; 4.34 ng/mL with 51.4% sensitivity and 100% specificity, and a P-value < 0.001 in discriminating PCOS cases. In conclusion, a strong positive correlation of visfatin with insulin resistance, followed by FAI in PCOS cases irrespective of BMI, suggests the intimate relation of visfatin in PCOS pathophysiology among non-obese women. Further research is warranted to explore this association's therapeutic and prognostic value.