Aberrant expression and DNA methylation of lipid metabolism genes in PCOS: a new insight into its pathogenesis

CTBP1 links metabolic syndrome to polycystic ovary syndrome through interruption of aromatase and SREBP1

Some patients with polycystic ovarian syndrome (PCOS) suffered from metabolic syndrome (MetS) including dyslipidemia, hyperinsulinism, but the underlying mechanism is unclear. Although C-terminal Binding Protein 1 (CTBP1) is a transcriptional co-repressor frequently involved in hormone secretion disorders and MetS-associated diseases, the role of CTBP1 in PCOS is rarely reported. In the present study, we found that CTBP1 expression was significantly elevated in primary granulosa cells (pGCs) derived from the PCOS with MetS patients and was positively associated with serum triglyceride, but negatively correlated with serum estradiol (E2) or high-density lipoprotein. Mechanistic study suggested that CTBP1 physically bound to the promoter II of cytochrome P450 family 19 subfamily A member 1 (CYP19A1) to inhibit the aromatase gene transcription and expression, resulting in the reduced E2 synthesis. Moreover, CTBP1 interacted with the phosphorylated SREBP1a at S396 in nuclei, leading to the FBXW7-dependent protein degradation, resulting in the reduced lipid droplets formation in pGCs. Therefore, we conclude that CTBP1 in GCs dysregulates the synthesis of steroid hormones and lipids through suppression of aromatase expression and promotion of SREBP1a protein degradation in PCOS patients, which may offer some fresh insights into the potential pathological mechanism for this tough disease.

The prevalence and odds of bipolar disorder in women with polycystic ovary syndrome (PCO) disease: a systematic review and meta-analysis

BACKGROUND

Women with polycystic ovary syndrome (PCO) suffer from psychological difficulties like bipolar disorder. Various studies in the literature report several prevalence rates of bipolar disorder in women with PCO, while there is no systematic review in this field. So, we designed this systematic review and meta-analysis to estimate the pooled prevalence and odds of bipolar disorder in women with PCO disease.

METHOD

PubMed, Scopus, EMBASE, Web of Science, Google Scholar, and references of the references, conference abstracts were comprehensively searched by two independent researchers. The search was done on May 1st, 2023.

RESULTS

A literature search revealed 438 records, 35 full texts were evaluated, and finally, 11 studies remained for systematic review. Totally, 73,102 women with PCO and 340,724 controls were evaluated. Among cases, 1471 had bipolar diagnosis vs. 4321 controls. The prevalence of bipolar disorder in women with PCO ranged between 0 and 27%, and the pooled prevalence was estimated as 4% (95% CI, 2-5%; I2, 99.3%, p < 0.001). The odds of bipolar disorder in women with PCO ranged between 0.98 and 8.78, and the pooled estimate was 2.06 (95% CI, 1.61-2.63) (I2, 85.6%; p < 0.001).

CONCLUSIONS

This systematic review and meta-analysis show that the pooled prevalence of bipolar disorder in women with PCO is 4%, and women with PCO are at a 2-fold higher risk of bipolar disorder.

Role of the mitophagy-apoptosis axis in the pathogenesis of polycystic ovarian syndrome

AIM

Polycystic ovary syndrome (PCOS) is a common endocrine disorder characterized by menstrual irregularities, androgen excess, and polycystic ovarian morphology, but its pathogenesis remains largely unknown. This review focuses on how androgen excess influences the molecular basis of energy metabolism, mitochondrial function, and mitophagy in granulosa cells and oocytes, summarizes our current understanding of the pathogenesis of PCOS, and discuss perspectives on future research directions.

METHODS

A search of PubMed and Google Scholar databases were used to identify relevant studies for this narrative literature review.

RESULTS

Female offspring born of pregnant animals exposed to androgens recapitulates the PCOS phenotype. Abnormal mitochondrial morphology, altered expression of genes related to glycolysis, mitochondrial biogenesis, fission/fusion dynamics, and mitophagy have been identified in PCOS patients and androgenic animal models. Androgen excess causes uncoupling of the electron transport chain and depletion of the cellular adenosine 5'-triphosphate pool, indicating further impairment of mitochondrial function. A shift toward mitochondrial fission restores mitochondrial quality control mechanisms. However, prolonged mitochondrial fission disrupts autophagy/mitophagy induction due to loss of compensatory reserve for mitochondrial biogenesis. Disruption of compensatory mechanisms that mediate the quality control switch from mitophagy to apoptosis may cause a disease phenotype. Furthermore, genetic predisposition, altered expression of genes related to glycolysis and oxidative phosphorylation, or a combination of these factors may also contribute to the development of PCOS.

CONCLUSION

In conclusion, fetuses exposed to a hyperandrogenemic intrauterine environment may cause the PCOS phenotype possibly through disruption of the compensatory regulation of the mitophagy-apoptosis axis.

Metabolome implies increased fatty acid utilization and histone methylation in the follicles from hyperandrogenic PCOS women

Well-balanced metabolism is essential for the high-quality of oocytes, and metabolic fluctuations of follicular microenvironment potentially encourage functional changes in follicle cells, ultimately impacting the developmental potential of oocytes. Here, the global metabolomic profiles of follicular fluid from PCOS women with ovarian hyperandrogenism and nonhyperandrogenism were depicted by untargeted metabolome and transcriptome. In parallel, functional methods were employed to evaluate the possible impact of dysregulated metabolites on oocyte and embryo development. Our findings demonstrated that PCOS women exhibited distinct metabolic features in follicles, such as the increase in fatty acid utilization and the downregulation in amino acid metabolism. And intrafollicular androgen levels were positively correlated with contents of multiple fatty acids, suggesting androgen as one of the contributing factors to the metabolic abnormalities in PCOS follicles. Moreover, we further demonstrated that elevated levels of α-linolenic acid and H3K27me3 could hinder oocyte maturation, fertilization, and early embryo development. Hopefully, our data serve as a broad resource on the metabolic abnormalities of PCOS follicles, and advances in the relevant knowledge will allow the identification of biomarkers that predict the progression of PCOS and its poor pregnancy outcomes.

DNA Hypomethylation-Mediated Transcription Dysregulation Participates in Pathogenesis of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a highly heterogeneous and genetically complex endocrine disorder. Although the etiology remains mostly elusive, growing evidence suggested abnormal changes of DNA methylation correlate well with systemic and tissue-specific dysfunctions in PCOS. A dehydroepiandrosterone-induced PCOS-like mouse model was generated, which has a similar metabolic and reproductive phenotype as human patients with PCOS, and was used to experimentally validate the potential role of aberrant DNA methylation in PCOS in this study. Integrated DNA methylation and transcriptome analysis revealed the potential role of genomic DNA hypomethylation in transcription regulation of PCOS and identified several key candidate genes, including BMP4, Adcy7, Tnfaip3, and Fas, which were regulated by aberrant DNA hypomethylation. Moreover, i.p. injection of S-adenosylmethionine increased the overall DNA methylation level of PCOS-like mice and restored expression of the candidate genes to similar levels as the control, alleviating reproductive and metabolic abnormalities in PCOS-like mice. These findings provided direct evidence showing the importance of normal DNA methylation in epigenetic regulation of PCOS and potential targets for diagnosis and treatment of the disease.

LncRNA SNHG5 adversely governs follicular growth in PCOS via miR-92a-3p/CDKN1C axis

Small nucleolar RNA host genes (SNHGs) have been implicated in various biological processes, yet their involvement in polycystic ovary syndrome (PCOS) remains elusive. Specifically, SNHG5, a long non-coding RNA implicated in several human cancers, shows elevated expression in granulosa cells (GCs) of PCOS women and induces PCOS-like features when overexpressed in mice. In vitro, SNHG5 inhibits GC proliferation and induces apoptosis and cell-cycle arrest at G0/G1 phase, with RNA-seq indicating its impact on DNA replication and repair pathways. Mechanistically, SNHG5 acts as a competing endogenous RNA by binding to miR-92a-3p, leading to increased expression of target gene CDKN1C, which further suppresses GC proliferation and promotes apoptosis. These findings elucidate the crucial role of SNHG5 in the pathogenesis of PCOS and suggest a potential therapeutic target for this condition. Additional investigations such as large-scale clinical studies and functional assays are warranted to validate and expand upon these findings.

DNA methylation associated with polycystic ovary syndrome: a systematic review

PURPOSE

Polycystic ovary syndrome (PCOS) is an endocrine metabolic disease that affects women of reproductive age and is one of the main causes of anovulatory infertility. However, the cause of PCOS is yet fully understood, and genetic factors play an important role in its etiology. In this study, we reviewed the main genes involved in the etiology of PCOS and the influence of DNA methylation, aiming to answer the study´s guiding question: 'What is the influence of DNA methylation on the main genes involved in PCOS?'.

METHODS

We used the MEDLINE database, and inclusion criteria (primary and original articles, written in English, found through our entry terms) and exclusion criteria (literature reviews and articles that used animals to perform the experiments and that focused in other epigenetics mechanism without being DNA methylation) were applied.

RESULTS

Twenty-three scientific articles, from a total of 43 articles read in full, were chosen for this study. Eighteen studies confirmed DNA methylation associated with PCOS.

CONCLUSION

The most relevant genes related to PCOS were INSR, LHCGR, and RAB5B, which may be epigenetically altered in DNA, with the first two genes hypomethylated and the last hypermethylated. The epigenetic changes presented in the genes related to PCOS or their promoters were only at the CpG sites.

Long pentraxin 3 and vitamin D receptor mRNA expression pattern of cumulus granulosa cells isolated from PCOS oocytes at different stages of nuclear maturation

BACKGROUND

A fine-tuned pro-inflammatory and anti-inflammatory balance in the follicular unit is essential for cumulus expansion and successful ovulation. While the long pentraxin 3 (PTX3) gene is required for the expansion of cumulus cells (CCs), ovulation, resumption of meiosis and fertilization, the vitamin D receptor gene (VDR-X2) is required for intra-follicle redox balance. This study was planned to determine the expression pattern of VDR-X2 and PTX3 mRNA in CCs isolated from germinal vesicle (GV), metaphase I (MI), and metaphase II (MII) oocytes of PCOS patients with ovulatory dysfunction.

METHODS

The relative expression of CC-PTX3 and CC-VDR-X2 mRNA were evaluated using qRT-PCR in a total of 79 CC samples collected from individual cumulus-oocyte complex of 40 infertile patients (20 PCOS and 20 non-PCOS normal responders) who underwent ovarian stimulation with the GnRH antagonist protocol.

RESULTS

Relative PTX3 mRNA expressions of CCMI-control and CCMII-control showed 3- and 9-fold significant upregulation compared to CCGV-control, respectively. The relative PTX3 mRNA expression of CCMII-control increased approximately three fold compared to CCMI-control. Compared to CCGV-pcos, a 3-fold increase was noted in the relative PTX3 mRNA expression of CCMI-pcos and an approximately 4-fold increase in the PTX3 mRNA expression of CCMII-pcos. Relative PTX3 mRNA expression values of CCMII-pcos and CCMI-pcos were similar. A 6-fold upregulation of relative PTX3 mRNA and a 4-fold upregulation of VDR-X2 mRNA were detected in CCMII-control compared to CCMII-pcos. CC-VDR-X2 expression patterns of the PCOS and control groups overlapped with the CC-PTX3 pattern. Fertilization rates of the PCOS group exhibiting failed transcript expression were similar to normal responders.

CONCLUSION

The fact that relative CC-PTX3 and CC-VDR mRNA expression does not increase during the transition from MI to MII stage in PCOS as in normal responders suggests that PTX3 and VDR expression may be defective in cumulus cells of PCOS patients with ovulatory dysfunction.

Ampelopsis japonica aqueous extract improves ovulatory dysfunction in PCOS by modulating lipid metabolism

Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine and metabolic disorder that is closely associated with the proliferation and apoptosis of ovarian granulosa cells (GCs). Ampelopsis japonica (AJ) is the dried tuberous root of Ampelopsis japonica (Thunb.) Makino (A. japonica), with anti-inflammatory, antioxidant, antibacterial, antiviral, wound-healing, and antitumor properties; however, it is unclear whether this herb has a therapeutic effect on PCOS. Therefore, this study aimed to investigate the pharmacological effect of AJ on PCOS and reveal its potential mechanism of action. A PCOS rat model was established using letrozole. After establishing the PCOS model, the rats received oral treatment of AJ and Diane-35 (Positive drug: ethinylestradiol + cyproterone tablets) for 2 weeks. Lipidomics was conducted using liquid-phase mass spectrometry and chromatography. AJ significantly regulated serum hormone levels and attenuated pathological variants in the ovaries of rats with PCOS. Furthermore, AJ significantly reduced the apoptotic rate of ovarian GCs. Lipidomic analysis revealed that AJ modulated glycerolipid and glycerophospholipid metabolic pathways mediated by lipoprotein lipase (Lpl), diacylglycerol choline phosphotransferase (Chpt1), and choline/ethanolamine phosphotransferase (Cept1). Therefore, we established that AJ may reduce ovarian GC apoptosis by modulating lipid metabolism, ultimately improving ovulatory dysfunction in PCOS. Therefore, AJ is a novel candidate for PCOS treatment.

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.

Promising drug candidates for the treatment of polycystic ovary syndrome (PCOS) as alternatives to the classical medication metformin

Polycystic ovary syndrome (PCOS) is a prevalent hormonal disorder that affects women of reproductive age. It is characterized by abnormal production of androgens, typically present in small quantities in females. This study aimed to investigate the therapeutic potential of Irosustat (STX64), STX140, and compound 1G as new drug candidates for the treatment of letrozole-induced PCOS in female Wistar rats. 36 rats were divided into six groups of equal size. PCOS was induced in all groups, except the normal control group, by administering letrozole orally (1 mg/kg/day for 35 days). The onset of abnormal estrous cycle was confirmed by examining daily vaginal smears under a microscope. Subsequently, each rat group was assigned to a different treatment regimen, including one control group, one letrozole group, one metformin group (500 mg/kg/day) as a reference drug, and the other groups received a different drug candidate orally for 30 days. After treatment, blood collection was performed for biochemical measurements and determination of oxidative stress markers. The rats were dissected to separate ovaries and uterus for morphological, histological, and western blotting studies. Treatment with the drug candidates improved the ovaries and uterus weight measurements compared to the untreated PCOS group. The three tested drug candidates demonstrated promising improvements in lipid profile, blood glucose level, testosterone, progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol levels. In addition, western blotting confirmed their promising effects on Akt, mTOR, and AMPK-α pathways. This study led to the discovery of three promising drug candidates for the management of PCOS as alternatives to metformin.

Selenium intake and multiple health-related outcomes: an umbrella review of meta-analyses

Selenium is an essential trace metalloid element that is associated with fundamental importance to human health. Our umbrella review aimed to evaluate the quality of evidence, validity, and biases in the relationship between selenium intake and health-related outcomes according to published systematic reviews with pooled data and meta-analyses. Selenium intake is associated with a decreased risk of digestive system cancers, all-cause mortality, depression, and Keshan disease, when in children reduce the risk of Kashin-Beck disease. Additionally, selenium supplementation can improve sperm quality, polycystic ovary syndrome, autoimmune thyroid disease, cardiovascular disease, and infective outcomes. Selenium supplementation also has relationship with a decreased concentration of serum lipids including total cholesterol and very low-density lipoprotein cholesterol. However, no evidence has shown that selenium is associated with better outcomes among patients in intensive care units. Furthermore, selenium intake may be related with a higher risk of type 2 diabetes and non-melanoma skin cancers. Moreover, most of included studies are evaluated as low quality according to our evidence assessment. Based on our study findings and the limited advantages of selenium intake, it is not recommended to receive extra supplementary selenium for general populations, and selenium supplementation should not be continued in patients whose selenium-deficient status has been corrected.

Analysis of Methylome, Transcriptome, and Lipid Metabolites to Understand the Molecular Abnormalities in Polycystic Ovary Syndrome

Purpose

This study aimed to identify differentially methylated genes (DMGs) and differentially expressed genes (DEGs) to investigate new biomarkers for the diagnosis and treatment of polycystic ovary syndrome (PCOS).

Methods

To explore the potential biomarkers of PCOS diagnosis and treatment, we performed methyl-binding domain sequencing (MBD-seq) and RNA sequencing (RNA-seq) on ovarian granulosa cells (GCs) from PCOS patients and healthy controls. MBD-seq was also performed on the ovarian tissue of constructed prenatally androgenized (PNA) mice. Differential methylation and expression analysis were implemented to identify DMGs and DEGs, respectively. The identified gene was further verified by real-time quantitative PCR (RT-qPCR) and methylation-specific PCR (MSP) in clinical samples. Furthermore, ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) was carried out on PCOS patients and healthy controls to identify differential lipid metabolites.

Results

Compared to the control group, 13,526 DMGs related to the promoter region and 2429 DEGs were found. The function analysis of DMGs and DEGs showed that they were mainly enriched in glycerophospholipid, ovarian steroidogenesis, and other lipid metabolic pathways. Moreover, 5753 genes in DMGs related to the promoter region were screened in the constructed PNA mice. Integrating the DMGs data from PCOS patients and PNA mice, we identified the following 8 genes: CDC42EP4, ERMN, EZR, PIK3R1, ARHGEF18, NECTIN2, TSC2, and TACSTD2. RT-qPCR and MSP verification results showed that the methylation and expression of TACSTD2 were consistent with sequencing data. Additionally, 15 differential lipid metabolites were shown in the serum of PCOS patients. The differential lipids were involved in glycerophospholipid and glycerolipid metabolism.

Conclusion

Using integration of methylome and lipid metabolites profiling we identified 8 potential epigenetic markers and 15 potential lipid metabolite markers for PCOS. Our results suggest that aberrant DNA methylation and lipid metabolite disorders may provide novel insights into the diagnosis and etiology of PCOS.

Obesity and Dyslipidemia: A Review of Current Evidence

PURPOSE OF REVIEW

Obesity is accompanied by atherogenic dyslipidemia, a specific lipid disorder characterized by both quantitative and qualitative changes of plasma lipoproteins. The main alterations in the lipid profile include hypertriglyceridemia, reduced high-density lipoprotein (HDL) cholesterol level, and elevated small dense low-density lipoprotein (LDL) particles. Epidemiological data show that obesity is more common in women and is a frequent risk factor for reproductive disorders, metabolic complications in pregnancy, and cardiometabolic disease later in life. The aim of this narrative review is to discuss recent advances in the research of dyslipidemia in obesity, with an emphasis on female-specific disorders and cardiometabolic risk.

RECENT FINDINGS

The focus of current research on dyslipidemia in obesity is moving toward structurally and functionally modified plasma lipoproteins. Special attention is paid to the pro-atherogenic role of triglyceride-rich lipoproteins and their remnants. Introduction of advanced analytical techniques enabled identification of novel lipid biomarkers with potential clinical applications. In particular, proteomic and lipidomic studies have provided significant progress in the comprehensive research of HDL's alterations in obesity. Obesity-related dyslipidemia is a widespread metabolic disturbance in polycystic ovary syndrome patients and high-risk pregnancies, but is seldom evaluated with respect to its impact on future cardiometabolic health. Obesity and associated cardiometabolic diseases require a more depth insight into the quality of lipoprotein particles. Further application of omics-based techniques would enable a more comprehensive evaluation of dyslipidemia in order to reduce an excessive cardiovascular risk attributable to increased body weight. However, more studies on obesity-related female reproductive disorders are needed for this approach to be adopted in daily clinical practice.

A New Approach to Polycystic Ovary Syndrome and Related Cardio-metabolic Risk Factors: Dietary Polyphenols

PURPOSE OF REVIEW

Polycystic ovarian syndrome (PCOS) is a common endocrine disease characterized by ovulatory dysfunction, hyperandrogenism, and polycystic ovarian morphology and causing various reproductive, metabolic, cardiovascular, oncological, and psychological complications. Recent meta-analyses and systemic reviews showed that PCOS increases the risk factor for various cardio-metabolic complications like insulin resistance, type II diabetes mellitus, dyslipidemia, metabolic syndrome, hypertension, and endothelial dysfunction. In addition to these, it was suggested that chronic low-grade inflammation and oxidative stress are the underlying mechanisms of PCOS-mediated metabolic consequences and might trigger cardio-metabolic risk in women with PCOS. At this point, there is substantial evidence to suggest that various non-nutrient food components modulate cardio-metabolic health together with inflammation and oxidative stress.

RECENT FINDINGS

Increasing the intake of dietary polyphenols might reduce oxidative stress and inflammation and thus alleviate the risk of metabolic, endothelial, and cardiovascular disorders. Nowadays, there are an increasing number of studies related to the effects of dietary polyphenols on PCOS and its accompanying cardio-metabolic disturbances. Currently, there is a cumulative number of studies connected to the effects of dietary polyphenols on PCOS and accompanying cardio-metabolic disturbances. However, there is a lack of knowledge in combining the probable mechanisms of dietary polyphenols on PCOS and related cardio-metabolic consequences. Thus, the effects of dietary polyphenols on PCOS and accompanying cardio-metabolic disturbances need to be discussed and evaluated with underlying mechanisms. Consequently, this review was written to reveal the potential effects of dietary polyphenols on PCOS and related metabolic and cardiovascular risk factors in all their aspects.

Evaluation of the efficacy of an antioxidant combination for the modulation of metabolic, endocrine, and clinical parameters in patients with polycystic ovary syndrome

OBJECTIVE

To evaluate the efficacy of dietary supplementation with a combination of antioxidants (lipoic acid, N-acetylcysteine, vitamin B₆, and S-adenosyl-L-methionine) for the modulation of metabolic, endocrine, and clinical parameters in comparison with oral contraception in non-diabetic women newly diagnosed with polycystic ovary syndrome (PCOS).

METHODS

This was a prospective, partially randomized, multicenter study in which non-diabetic women with PCOS were recruited under routine clinical practice conditions and distributed in three groups to receive the following regimen for 6 months: 1) antioxidant combination (MN group); 2) oral contraception (OC group); or 3) oral contraception and the antioxidant combination (MN + OC group). General recommendation of healthy diet and regular exercise was given to all patients. Metabolic, endocrine, clinical, and quality of life parameters were recorded at baseline and after 6 months of therapy.

RESULTS

A total of 96 women with PCOS were included in the study. After 6 months of treatment, the homeostasis model assessment-estimated insulin resistance (HOMA-IR) level was reduced only in the MN group, with a significant mean reduction of -0.92 points. Androstenedione was significantly reduced in all groups. Clinical parameters that significantly improved in all groups were hirsutism, acne, irregular menstruation, and quality of life, with no statistical differences between the groups.

CONCLUSIONS

This study showed that the antioxidant combination might be a suitable therapy for patients with PCOS when oral contraceptive is not indicated, because in all groups clinical parameters, irregular menstruation as well as androstenedione and quality of life were significantly improved with no statistical difference between groups.

Depression, sexual function and sexual quality of life in women with polycystic ovary syndrome (PCOS) and healthy subjects

BACKGROUND

Women with polycystic ovary syndrome (PCOS) suffer from a wide range of psychological problems. The goal of this study is to assess depression, sexual dysfunction and sexual quality of life in women with PCO compared with healthy subjects.

METHODS

One hundred and six PCO cases and 106 healthy subjects enrolled. They were asked to fill out valid and reliable Persian versions of BDI (Beck depression inventory), FSFIS (Female Sexual Function Index), and sexual quality of life-Female (SQOL-F) questionnaires.

RESULTS

One hundred and six PCO cases and 106 healthy subjects enrolled. Mean BDI was significantly higher while FSFI and its subscales as well as SQOL-F were significantly lower in PCO group than controls. There were significant negative correlation between FSFO and BDI (r=-0.43, p < 0.001) and also positive correlation between FSFI and SQOL-F (r = 0.438, p < 0.001) in whole population of the study. In PCO group, 77 (72.6%) had FSFI less than 26.55 and 29 (27.4%) had score more than 26.55. mean BDI was significantly higher in the group with FSFI < = 26.55 than the other group (33 ± 14.4 vs. 12 ± 11.6, p < 0.001) while SLQL-F was significantly lower in the first group (57 ± 16 vs. 74.9 ± 17.6, p < 0.001). Linear regression analysis by considering SQOL-F as dependent and FSFI, age and BDI as independent variables showed that BDI and FSFI are independent predictors.

CONCLUSION

Women with PCO, suffer more from depression and sexual dysfunction than healthy subjects.

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.

Updates on Molecular Targets and Epigenetic-Based Therapies for PCOS

Polycystic ovarian syndrome (PCOS) can cause infertility in females due to hyperandrogenism and neuroendocrine abnormalities. The aim of this study is to decipher the impact of endocrine variables, hyperandogenism, insulin resistance, oxidative stress, and dietary conditions in PCOS conditions, subsequently to depict the role of epigenetic factors relative to phenotypic manifestations in PCOS conditions. We have reviewed several metabolic milieus pertinent to PCOS conditions. Comparative efficacies of various PCOS therapies, and recent clinical recommendations for the effective management of PCOS and role of metabolic/endocrine variables in PCOS conditions were described. Comparative therapeutic effects were vividly delineated according to the variable pathophysiology and internal variables during PCOS syndrome on the female body through the formation of cascade of endocrine pathology, which affects working capacity and fosters redox stress-induced cardiovascular, neural, and liver abnormalities. GLP-1 agonists, insulin sensitizers (metformin), and diet and exercise regimens efficacy were explained in enhancing the fertility outcomes among the overweight or obese females with PCOS. Comprehensive appraisal of DNA methylation as epigenetic changes and the manifestations of methylated genes in PCOS conditions were discussed particularly to screen novel molecular targets for developing efficient diagnostic indicators for predicting PCOS risk or its progression. Due to the reversible nature of epigenetic modifications, it is possible to screen the "druggable" regions to target or to correct abnormalities in the gene expression subsequently to develop chromatin-modifying therapies against PCOS.

Effects of selenium supplementation on Polycystic Ovarian Syndrome: a systematic review and meta-analysis on randomized clinical trials

BACKGROUND

This study provides a systematic review and meta-analysis of randomized controlled trials, which examined the effect of the selenium supplementation on polycystic ovary syndrome (PCOS).

METHODS

Confirmed studies related to selenium supplementation and PCOS were searched from the databases of EMBASE, PubMed and Web of Science. Data were reported as weighted mean difference (WMD) or standard mean difference (SMD) and associated 95% confidence intervals (CIs). Analysis was performed with Stata version 12.0.

RESULTS

A total of 389 cases (selenium group n = 195, control group n = 194) were included in this studies. This meta-analysis showed that selenium supplementation has a positive effect on TAC, and supplementation of selenium does not significantly improve the level of BMI, Weight, LDL, HDL, Triglycerides, Total Testosterone, HOMA-IR, NO, GSH, MDA and FPG.

CONCLUSION

Although selenium can improve TAC in PCOS patients, it has no significant effect on BMI, Total Testosterone, et al. In terms of the results of this meta-analysis, it is not recommended for patients with PCOS to use selenium as a regular trace element supplement. Based on the improving effect of selenium on TAC, supplementation of selenium may have a positive effect on improving follicle quality for some PCOS patients who have poor follicle quality caused by oxidative stress or who want to undergo IVF.

Biomechanical forces and signals operating in the ovary during folliculogenesis and their dysregulation: implications for fertility

BACKGROUND

Folliculogenesis occurs in the highly dynamic environment of the ovary. Follicle cyclic recruitment, neo-angiogenesis, spatial displacement, follicle atresia and ovulation stand out as major events resulting from the interplay between mechanical forces and molecular signals. Morphological and functional changes to the growing follicle and to the surrounding tissue are required to produce oocytes capable of supporting preimplantation development to the blastocyst stage.

OBJECTIVE AND RATIONALE

This review will summarize the ovarian morphological and functional context that contributes to follicle recruitment, growth and ovulation, as well as to the acquisition of oocyte developmental competence. We will describe the changes occurring during folliculogenesis to the ovarian extracellular matrix (ECM) and to the vasculature, their influence on the mechanical properties of the ovarian tissue, and, in turn, their influence on the regulation of signal transduction. Also, we will outline how their dysregulation might be associated with pathologies such as polycystic ovary syndrome (PCOS), endometriosis or premature ovarian insufficiency (POI). Finally, for each of these three pathologies, we will highlight therapeutic strategies attempting to correct the altered biomechanical context in order to restore fertility.

SEARCH METHODS

For each area discussed, a systematic bibliographical search was performed, without temporal limits, using PubMed Central, Web of Science and Scopus search engines employing the keywords extracellular matrix, mechanobiology, biomechanics, vasculature, angiogenesis or signalling pathway in combination with: ovary, oogenesis, oocyte, folliculogenesis, ovarian follicle, theca, granulosa, cumulus, follicular fluid, corpus luteum, meiosis, oocyte developmental competence, preimplantation, polycystic ovary syndrome, premature ovarian insufficiency or endometriosis.

OUTCOMES

Through search engines queries, we yielded a total of 37 368 papers that were further selected based on our focus on mammals and, specifically, on rodents, bovine, equine, ovine, primates and human, and also were trimmed around each specific topic of the review. After the elimination of duplicates, this selection process resulted in 628 papers, of which 287 were cited in the manuscript. Among these, 89.2% were published in the past 22 years, while the remaining 8.0%, 2.4% or 0.3% were published during the 1990s, 1980s or before, respectively. During folliculogenesis, changes occur to the ovarian ECM composition and organization that, together with vasculature modelling around the growing follicle, are aimed to sustain its recruitment and growth, and the maturation of the enclosed oocyte. These events define the scenario in which mechanical forces are key to the regulation of cascades of molecular signals. Alterations to this context determine impaired folliculogenesis and decreased oocyte developmental potential, as observed in pathological conditions which are causes of infertility, such as PCOS, endometriosis or POI.

WIDER IMPLICATIONS

The knowledge of these mechanisms and the rules that govern them lay a sound basis to explain how follicles recruitment and growth are modulated, and stimulate insights to develop, in clinical practice, strategies to improve follicular recruitment and oocyte competence, particularly for pathologies like PCOS, endometriosis and POI.

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

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

Mechanism of Mitochondrial Homeostasis Controlling Ovarian Physiology

Ovarian cells, including oocytes, granulosa/cumulus cells, theca cells, and stromal cells, contain abundant mitochondria, which play indispensable roles in the processes of ovarian follicle development. Ovarian function is closely controlled by mitochondrial proteostasis and mitostasis. While mitochondrial proteostasis and mitostasis are disturbed by several factors, leading to dysfunction of ovarian function and initiating the mitochondrial unfolded protein response (UPRmt) and mitophagy to maintain or recover ovarian function and mitochondrial function, clear interactions between the 2 pathways in the ovary have not been fully elucidated. Here, we comprehensively summarize the molecular networks or regulatory mechanisms behind further mitochondrial research in the ovary. This review provides novel insights into the interactions between the UPRmt and mitophagy in ovarian functions.

Hypermethylation of tumor suppressor lncRNA MEF2C-AS1 frequently happened in patients at all stages of colorectal carcinogenesis

Background

The novel long noncoding RNA MEF2C-AS1 has been identified to play suppressor roles during tumorigenesis. DNA methylation has a regulatory effect on gene expression in cancer initiation and progression. However, the methylation status of MEF2C-AS1 and its role in colorectal cancer (CRC) development remain unclear.

Methods

The expression and methylation levels of MEF2C-AS1 were systematically analyzed among 31 cancers with available qualified data in GEPIA and UCSC Xena databases. Then, the MEF2C-AS1 methylation status was firstly examined among 12 CRCs by Illumina Infinium MethylationEPIC BeadChip in in-house step 1 and further quantified among 48 CRCs by the MassARRAY method in in-house step 2. Subsequently, its methylation and expression levels were quantified among 81 non-advanced adenomas (NAAs), 81 advanced adenomas (AAs), and 286 CRCs using the MassARRAY method, and among 34 NAAs, 45 AAs, and 75 CRCs by qRT-PCR, in in-house step 3, respectively. The effect of MEF2C-AS1 methylation on CRC survival was analyzed by the Kaplan–Meier method. Additionally, in vitro cell proliferation, migration and invasion assays, and bioinformatics analysis were performed to explore the role of MEF2C-AS1 in colorectal carcinogenesis.

Results

Lower expression and higher methylation of MEF2C-AS1 were found in CRC by online databases. In the comparisons of lesion tissues with adjacent normal tissues, MEF2C-AS1 hypermethylation of each individual site and mean level was found among CRC patients in in-house step 1 and step 2, more meaningfully, among NAA patients, AA patients, and CRC patients at all stages during colorectal carcinogenesis in in-house step 3 (all p < 0.05). Further comparisons demonstrated significant differences between CRC and NAA (p = 0.025), AA and NAA (p = 0.020). Moreover, MEF2C-AS1 hypermethylation was associated with poorer disease-specific survival of CRC patients (p = 0.044). In addition, hypermethylation and lower expression of MEF2C-AS1 were verified in RKO cells, and the MEF2C-AS1 overexpression significantly suppressed RKO cell proliferation, migration, and invasion.

Conclusions

The findings reveal that MEF2C-AS1 hypermethylation might be an early driven event during colorectal carcinogenesis. It might serve as a promising prognostic biomarker for CRC survival. Our study also indicates the potential tumor-suppressing role of MEF2C-AS1 in CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-022-01328-1.

Role of genomic DNA methylation in PCOS pathogenesis: a systematic review and meta-analysis involving case controlled clinical studies

PCOS is often associated with aberrant DNA methylation. Despite the advances in diagnostics and treatment of PCOS, the pathophysiological mechanism remain unknown. Several genes are epigenetically dysregulated in PCOS and associated with pathological consequences of PCOS and metabolic comorbidities, however the methylation status of specific genes and to what extent the genes are deregulated in terms of methylation pattern are unknown. This review aimed to analyse the existing data for specific genes and find conclusive evidence of their involvement in PCOS and associated risks. A comprehensive literature search was conducted in five electronic databases. The case-controlled clinical studies using both PCOS and healthy women and evaluating the methylation pattern without any treatment or intervention were included in the study. A random-effect model was used to extract the data for meta-analysis, and outcomes were expressed as standardized mean difference with a 95% CI. From 541 screened records, 41 studies were included in the review and 21 of them were used for meta-analysis of 20 genes. Meta-analysis revealed a significant global DNA hypomethylation in different tissues and peripheral blood of patients with PCOS compared to healthy controls. Specific gene methylation assessment revealed that genes associated with several functions were significantly hypomethylated and hypermethylated in patients with PCOS. This review provides conclusive evidence of epigenetic deregulation of specific genes in PCOS. These genes can potentially be used to develop diagnostic biomarkers or as targets for personalised therapy.

Metabolism-Associated DNA Methylation Signature Stratifies Lower-Grade Glioma Patients and Predicts Response to Immunotherapy

Metabolism and DNA methylation (DNAm) are closely linked. The value of the metabolism-DNAm interplay in stratifying glioma patients has not been explored. In the present study, we aimed to stratify lower-grade glioma (LGG) patients based on the DNAm associated with metabolic reprogramming. Four data sets of LGGs from three databases (TCGA/CGGA/GEO) were used in this study. By screening the Kendall’s correlation of DNAm with 87 metabolic processes from KEGG, we identified 391 CpGs with a strong correlation with metabolism. Based on these metabolism-associated CpGs, we performed consensus clustering and identified three distinct subgroups of LGGs. These three subgroups were characterized by distinct molecular features and clinical outcomes. We also constructed a subgroup-related, quantifiable CpG signature with strong prognostic power to stratify LGGs. It also serves as a potential biomarker to predict the response to immunotherapy. Overall, our findings provide new perspectives for the stratification of LGGs and for understanding the mechanisms driving malignancy.

Metabolic and Molecular Mechanisms of Diet and Physical Exercise in the Management of Polycystic Ovarian Syndrome

Polycystic ovary syndrome (PCOS) is an endocrine systemic disorder mainly characterized by a hormonal and metabolic disbalance that leads to oligo/anovulation, hyperandrogenism and the formation of ovarian cysts. Despite the progress that has been reached in its diagnosis and management, little is known about the molecular mechanisms and signaling pathways underlying the pathogenic mechanisms. In this sense, recent research has suggested that the influence of multiple factors, including age, environment, lifestyle and the disease state environment can change the clinical presentation of PCOS via epigenetic modifications. Variants in the genes encoding for proteins involved in steroidogenesis and glucose homeostasis play a crucial role in the development of the disease. Other genes involved in inflammation and cell proliferation seem to undergo an epigenetic control. Moreover, lifestyle factors influence the PCOS course and prognosis, including diet and physical activity, which are fundamental in reducing oxidative stress, inflammation and in improving metabolic and hormonal parameters. In the present review, literature evidence on molecular and epigenetic mechanisms related to PCOS etiology will be discussed, with a particular attention on the positive influence of diet and physical activity as nonpharmacological ways of intervention in the management of the disease.

Evidence for TET-mediated DNA demethylation as an epigenetic alteration in cumulus granulosa cells of women with polycystic ovary syndrome

Peripheral and tissue-specific alterations in global DNA methylation (5mC) and hydroxymethylation (5hmC) profiles have been charted as biomarkers for disease prediction and as hallmarks of dysregulated localized gene networks. Global and gene-specific epigenetic alterations in the 5mC profiles have shown widespread implications in etiology of polycystic ovary syndrome (PCOS). However, there has been no study in PCOS that integrates the quantification of 5mC and 5hmC signatures alongside the expression levels of DNA methylating and demethylating enzymes as respective indicators of methylation and demethylation pathways. Having previously shown that the 5mC signatures are not greatly altered in PCOS, we assessed the global 5hmC levels in peripheral blood leukocytes (PBLs) and cumulus granulosa cells (CGCs) of 40 controls and 40 women with PCOS. This analysis revealed higher 5hmC levels in CGCs of PCOS women, indicating a more dominant demethylation pathway. Further, we assessed the transcript and protein expression levels of DNA demethylating and methylating enzymes, i.e. ten-eleven translocation methylcytosine dioxygenases (TET1, TET2, TET3) and DNA methyltransferases (DNMT1, DNMT3A and DNMT3B), respectively, in CGCs. The relative transcript and protein expression levels of all three TETs were found to be higher in women with PCOS; and the TET mRNA expression profiles were positively correlated with 5hmC levels in CGCs. Also, all three DNMT genes showed altered transcript expression in PCOS, although only the downregulated DNMT3A transcript was correlated with decreasing 5mC levels. At the protein level, the expression of DNMT1 (maintenance methylation enzyme) was higher, while that of DNMT3A (denovo methylation enzyme) was found to be lower in PCOS compared to controls. Overall, these results indicate that DNA methylation changes in CGCs of PCOS women may arise partly due to intrinsic alterations in the transcriptional regulation of TETs and DNMT3A.

DNA Methylation in Polycystic Ovary Syndrome：Emerging Evidence and Challenges

Polycystic ovary syndrome (PCOS) is a disease related to reproductive endocrine abnormalities in women of reproductive age, often accompanied by metabolic diseases such as hyperandrogenemia, insulin resistance and dyslipidemia. However, the etiology and mechanism of PCOS are still unclear. In recent years, more and more studies have found that epigenetic factors play an important role in PCOS. DNA methylation is the most widely studied epigenetic modification. At present, changes of DNA methylation have been found in serum, ovarian, hypothalamus, skeletal muscle, adipose tissue of PCOS patients, and these changes are closely related to insulin resistance, lipid metabolism and follicular development of PCOS. Although the current research on DNA methylation in PCOS is not in-depth, it indicated up a good direction for future research on the etiology and mechanism of PCOS. This review discussed the relationship between DNA methylation and PCOS. It is expected to help accelerate the application of DNA methylation in the diagnosis and treatment of PCOS.

Transcriptional and DNA Methylation Signatures of Subcutaneous Adipose Tissue and Adipose-Derived Stem Cells in PCOS Women

Polycystic ovary syndrome (PCOS) is often associated with metabolic syndrome features, including central obesity, suggesting that adipose tissue (AT) is a key organ in PCOS pathobiology. In this study, we compared both abdominal (ABD) and gluteofemoral (GF) subcutaneous AT in women with and without PCOS. ABD and GF subcutaneous ATs from PCOS and BMI/WHR-matched control women were analyzed by RT-qPCR, FACS and histology. ABD and GF adipose-derived stem cell (ASC) transcriptome and methylome were analyzed by RNA-seq and DNA methylation array. Similar to the control group with abdominal obesity, the GF AT of PCOS women showed lower expression of genes involved in lipid accumulation and angiogenesis compared to ABD depot. FACS analysis revealed an increase in preadipocytes number in both AT depots from PCOS. Further pathway analysis of RNA-seq comparisons demonstrated that the ASCs derived from PCOS are pro-inflammatory and exhibit a hypoxic signature in the ABD depot and have lower expression of adipogenic genes in GF depot. We also found a higher CpG methylation level in PCOS compared to control exclusively in GF-ASCs. Our data suggest that ASCs play an important role in the etiology of PCOS, potentially by limiting expansion of the healthy lower-body AT.

Mersal E, Razik H. Farrag A, M. Abdelmoneim A, M. Abdelmenem A, S. Salim M. Histomorphological Changes in a Rat Model of Polycystic Ovary Syndrome and the Contribution of Stevia Leaf Extract in Modulating the Ovarian Fibrosis, VEGF, and TGF-β Immunoexpressions: Comparison with Metformin

Polycystic ovary syndrome (PCOS) is a common endocrine disorder of fertile females. It has been reported that stevia leaf extract (SLE) has antidiabetic and antihyperlipidemic properties. Therefore, the current study hypothesized and investigated the role and mechanistic aspects of a natural sweetener; SLE in treating a rat model of letrozole-induced PCOS and to compare it with metformin. Thirty-five female Wistar albino rats were divided into 5 groups: control, PCOS-induced group (letrozole, 1 mg/kg/d, for 21 days), SLE, metformin, and combination-treated groups (300 mg/kg/d, for the next 28 days in SLE and metformin-treated groups). Vaginal smears were done. The levels of glucose, lipid, and hormonal profiles were measured in the serum meanwhile, malonyl dialdehyde (MDA), superoxide dismutase (SOD), and tumour necrosis factor (TNF-α) were measured in the ovary. Ovarian sections were subjected to hematoxylin and eosin, Masson, and immunohistochemical identification of VEGF and TGF-β followed by morphometric analysis. PCOS rats showed altered hormonal and lipid profiles, in addition to hyperglycemia. Also, the ovarian tissue levels of MDA and TNF-α were elevated, and SOD was decreased. Numerous cystic follicles, decrease/absence of corpora lutea, interstitial fibrosis with positive VEGF and TGF-β immunoreactivity were evident. SLE improved all altered parameters. SLE showed potential therapeutic merits in letrozole-induced PCOS via anti-inflammatory, antioxidant, anti-fibrotic, and angiogenesis regulating mechanisms. Its effects were almost comparable to metformin, and the combination of both has no further synergistic effect.

Ferroptosis inhibitor ferrostatin‑1 alleviates homocysteine‑induced ovarian granulosa cell injury by regulating TET activity and DNA methylation

Polycystic ovary syndrome is one of the most common endocrine and metabolic gynecological disorders, of which dysfunction of ovarian granulosa cells is a key contributing factor. The aim of the present study was to explore the role of ferrostatin-1 (Fer-1), a ferroptosis inhibitor, in a cell injury model established by homocysteine (Hcy)-induced ovarian granulosa KGN cell line and the potential underlying mechanism. Cell viability was measured using Cell Counting Kit-8 assay in the presence or absence of Hcy and Fer-1. Cell apoptosis was assessed using TUNEL staining and the expression levels of apoptosis-related proteins were measured using western blotting. To explore the effects of Fer-1 on oxidative stress in Hcy-treated ovarian granulosa cells, the levels of reactive oxygen species (ROS), malondialdehyde (MDA), lactate dehydrogenase (LDH) and glutathione (GSH) were measured using their corresponding kits. Furthermore, Fe²⁺ levels were assessed using Phen Green^™ SK labeling and western blotting was performed to measure the protein expression levels of ferroptosis-associated proteins GPX4, SLC7A11, ASCL4 and DMT1. Subsequently, DNA methylation and ten-eleven translocation (TET) 1/2 demethylase levels were also detected to evaluate the extent of overall DNA methylation in ovarian granulosa cells after Hcy treatment. The TET1/2 inhibitor Bobcat339 hydrochloride was applied to treat ovarian granulosa cells before evaluating the possible effects of Fer-1 on TET1/2 and DNA methylation. Fer-1 was found to markedly elevate ovarian granulosa cell viability following Hcy treatment. The apoptosis rate in Fer-1-treated groups was also markedly decreased, which was accompanied by downregulated Bax and cleaved caspase-3 expression and upregulated Bcl-2 protein expression. In addition, Fer-1 treatment reduced the levels of ROS, MDA and LDH whilst enhancing the levels of GSH. Fe²⁺ levels were significantly decreased following Fer-1 treatment, which also elevated glutathione peroxidase 4 expression whilst reducing solute carrier family 7 member 11, achaete-scute family BHLH transcription factor 4 and divalent metal transporter 1 protein expression. Fer-1 significantly inhibited DNA methylation and enhanced TET1/2 levels, which were reversed by treatment with Bobcat339 hydrochloride. Subsequent experiments on cell viability, oxidative stress, Fe²⁺ content, ferroptosis- and apoptosis-related proteins levels revealed that Bobcat339 hydrochloride reversed the effects of Fer-1 on ovarian granulosa Hcy-induced cell injury. These results suggest that Fer-1 may potentially protect ovarian granulosa cells against Hcy-induced injury by increasing TET levels and reducing DNA methylation.

Elevated RIF1 participates in the epigenetic abnormalities of zygotes by regulating histone modifications on MuERV-L in obese mice

BACKGROUND

Maternal obesity impairs embryonic developmental potential and significantly increases the risks of metabolic disorders in offspring. However, the epigenetic transmission mechanism of maternal metabolic abnormalities is still poorly understood.

METHODS

We established an obesity model in female mice by high-fat diet (HFD) feeding. The effects of the HFD on the developmental potential of oocytes and embryos, the metabolic phenotype, and epigenetic modifications were investigated. The efficacy of metformin administration was assessed. Finally, the regulatory pathway of epigenetic remodeling during zygotic genome activation (ZGA) was explored.

RESULTS

Maternal HFD consumption significantly impaired glucose tolerance and increased the risk of metabolic disorders in F0 and F1 mice. Maternal HFD consumption also decreased embryonic developmental potential, increased reactive oxygen species (ROS) and γH2AX levels, and reduced the mitochondrial membrane potential (MMP) within oocytes, causing high levels of oxidative stress damage and DNA damage. Starting with this clue, we observed significantly increased RIF1 levels and shortened telomeres in obese mice. Moreover, significant abnormal DNA methylation and histone modification remodeling were observed during ZGA in obese mice, which may be coregulated by RIF1 and the ZGA marker gene MuERV-L. Metformin treatment reduced RIF1 levels, and partially improved ZGA activation status by rescuing epigenetic modification remodeling in oocytes and preimplantation embryos of obese mice. RIF1 knockdown experiments employing Trim-Away methods showed that RIF1 degradation altered the H3K4me3 and H3K9me3 enrichment and then triggered the MuERV-L transcriptional activation. Moreover, ChIP-seq data analysis of RIF1 knockouts also showed that RIF1 mediates the transcriptional regulation of MuERV-L by changing the enrichment of H3K4me3 and H3K9me3 rather than by altered DNA methylation.

CONCLUSION

Elevated RIF1 in oocytes caused by maternal obesity may mediate abnormal embryonic epigenetic remodeling and increase metabolic risk in offspring by regulating histone modifications on MuERV-L, which can be partially rescued by metformin treatment.

Effects of Androgen Excess-Related Metabolic Disturbances on Granulosa Cell Function and Follicular Development

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disease in women of reproductive age. Ovarian dysfunction including abnormal steroid hormone synthesis and follicular arrest play a vital role in PCOS pathogenesis. Hyperandrogenemia is one of the important characteristics of PCOS. However, the mechanism of regulation and interaction between hyperandrogenism and ovulation abnormalities are not clear. To investigate androgen-related metabolic state in granulosa cells of PCOS patients, we identified the transcriptome characteristics of PCOS granulosa cells by RNA-seq. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of differentially expressed genes (DEGs) revealed that genes enriched in lipid metabolism pathway, fatty acid biosynthetic process and ovarian steroidogenesis pathway were abnormally expressed in PCOS granulosa cells in comparison with that in control. There are close interactions among these three pathways as identified by analysis of the protein-protein interaction (PPI) network of DEGs. Furthermore, in vitro mouse follicle culture system was established to explore the effect of high androgen and its related metabolic dysfunction on follicular growth and ovulation. RT-qPCR results showed that follicles cultured with dehydroepiandrosterone (DHEA) exhibited decreased expression levels of cumulus expansion-related genes (Has2, Ptx3, Tnfaip6 and Adamts1) and oocyte maturation-related genes (Gdf9 and Bmp15), which may be caused by impaired steroid hormone synthesis and lipid metabolism, thus inhibited follicular development and ovulation. Furthermore, the inhibition effect of DHEA on follicle development and ovulation was ameliorated by flutamide, an androgen receptor (AR) antagonist, suggesting the involvement of AR signaling. In summary, our study offers new insights into understanding the role of androgen excess induced granulosa cell metabolic disorder in ovarian dysfunction of PCOS patients.

Elevated plasma pentraxin-3 in polycystic ovary syndrome is associated with hyperandrogenism: a case-control study

BACKGROUND

Pentraxin 3 (PTX3) - a crucial humoral innate immunity component - is related to obesity and cardiovascular complications in women who suffer from polycystic ovary syndrome (PCOS). However, the circulating PTX3 level in PCOS is still debated. In this study, we aimed to evaluate PTX3 plasma levels in PCOS women of childbearing age, and find possible endocrine/metabolic factors that could affect this level.

METHODS

A total of 360 women were enrolled: 120 PCOS women and 240 body mass index (BMI) matched normally ovulating women. Blood samples were collected on the third day of natural menstrual cycle or from the bleeding after progesterone withdrawal. The PTX3 concentration was measured by immunoassay.

RESULTS

The PTX3 plasma level was significantly higher in PCOS women compared to controls. There was a positive correlation between PTX3 plasma level and PCOS diagnosis, overweight, cycle length, serum LH to FSH ratio, estradiol, total testosterone (TT) on the third day of menstrual cycle, antral follicle count (AFC), as well as uric acid. Multivariant linear regression analysis indicated that participants' serum PTX3 levels were proportional to the circulating TT level, existence of PCOS, basal estradiol level and AFC.

CONCLUSIONS

Overall, the circulating PTX3 level was elevated in PCOS women and significantly associated with the presence of hyperandrogenism. This study provided the basis for further in-depth researches regarding PTX3 role in PCOS pathophysiology.

Molecular Features of Polycystic Ovary Syndrome Revealed by Transcriptome Analysis of Oocytes and Cumulus Cells

Polycystic ovary syndrome (PCOS) is typically characterized by a polycystic ovarian morphology, hyperandrogenism, ovulatory dysfunction, and infertility. Furthermore, PCOS patients undergoing ovarian stimulation have more oocytes; however, the poor quality of oocytes leads to lower fertilization and implantation rates, decreased pregnancy rates, and increased miscarriage rates. The complex molecular mechanisms underlying PCOS and the poor quality of oocytes remain to be elucidated. We obtained matched oocytes and cumulus cells (CCs) from PCOS patients, compared them with age-matched controls, and performed RNA sequencing analysis to explore the transcriptional characteristics of their oocytes and CCs. Moreover, we validated our newly confirmed candidate genes for PCOS by immunofluorescence. Unsupervised clustering analysis showed that the overall global gene expression patterns and transposable element (TE) expression profiles of PCOS patients tightly clustered together, clearly distinct from those of controls. Abnormalities in functionally important pathways are found in PCOS oocytes. Notably, genes involved in microtubule processes, TUBB8 and TUBA1C, are overexpressed in PCOS oocytes. The metabolic and oxidative phosphorylation pathways are also dysregulated in both oocytes and CCs from PCOS patients. Moreover, in oocytes, differentially expressed TEs are not uniformly dispersed in human chromosomes. Endogenous retrovirus 1 (ERV1) elements located on chromosomes 2, 3, 4, and 5 are rather highly upregulated. Interestingly, these correlate with the most highly expressed protein-coding genes, including tubulin-associated genes TUBA1C, TUBB8P8, and TUBB8, linking the ERV1 elements to the occurrence of PCOS. Our comprehensive analysis of gene expression in oocytes and CCs, including TE expression, revealed the specific molecular features of PCOS. The aberrantly elevated expression of TUBB8 and TUBA1C and ERV1 provides additional markers for PCOS and may contribute to the compromised oocyte developmental competence in PCOS patients. Our findings may also have implications for treatment strategies to improve oocyte maturation and the pregnancy outcomes for women with PCOS.

Prediction of Gut Microbial Community Structure and Function in Polycystic Ovary Syndrome With High Low-Density Lipoprotein Cholesterol

Gut microbiota has been proved to be involved in the occurrence and development of many diseases, such as type 2 diabetes, obesity, coronary heart disease, etcetera. It provides a new idea for the pathogenesis of polycystic ovary syndrome (PCOS). Our study showed that the gut microbial community of PCOS with high low-density lipoprotein cholesterol (LDLC) has a noticeable imbalance. Gut microbiota of PCOS patients was significantly changed compared with CON, and these changes were closely related to LDLC. Gut microbiota may affect the metabolic level of PCOS patients through multiple metabolic pathways, and lipid metabolism disorder may further aggravate the imbalance of gut microbiota. Actinomycetaceae, Enterobacteriaceae and Streptococcaceae had high accuracy in the diagnosis of PCOS and the differentiation of subgroups, suggesting that they may play an important role in the diagnosis and treatment of PCOS in the future. Also, the model we built showed good specificity and sensitivity for distinguishing PCOS from CON (including L_CON and L_PCOS, H_CON and H_PCOS). In conclusion, this is the first report on the gut microbiota of PCOS with high LDLC, suggesting that in the drug development or treatment of PCOS patients, the difference of gut microbiota in PCOS patients with different LDLC levels should be fully considered.

Potential environmental toxicant exposure, metabolizing gene variants and risk of PCOS-A systematic review

Exposure of environmental toxicants such as potentially toxic metals and pesticides have largely been attributed to produce adverse effects on general women's health and to be more precise on the reproductive system. In order to explore exposure of toxicants and metabolizing gene variants as risk factor for polycystic ovarian syndrome (PCOS), literature search was carried out using the databases PubMed, Central Cochrane Library, Google Scholar, Science Direct with appropriate keywords upto 6 December 2020. While most of the studies indicate higher serum Cu concentration and lower concentration of Mn as risk factor, studies also report presence of higher pesticide concentration in PCOS women. Genes such as MTHFR, CYPs participate in the metabolism of toxicants and may show different response due to underlying genetic variants. Thus, toxicant exposure are to some extent responsible for the pathogenesis of syndrome through oxidative stress and endocrine disruption, but the susceptibility may vary due to the underlying genetic polymorphism of the exposed population.

Androgen-induced epigenetic modulations in the ovary

In recent years, androgens have emerged as critical regulators of female reproduction and women's health in general. While high levels of androgens in women are associated with polycystic ovary syndrome (PCOS), recent evidence suggests that a certain amount of direct androgen action through androgen receptor is also essential for normal ovarian function. Moreover, prenatal androgen exposure has been reported to cause developmental reprogramming of the fetus that manifests into adult pathologies, supporting the Developmental Origins of Health and Disease (DOHaD) hypothesis. Therefore, it has become imperative to understand the underlying mechanism of androgen actions and its downstream effects under normal and pathophysiological conditions. Over the years, there has been a lot of studies on androgen receptor function as a transcriptional regulator in the nucleus as well as androgen-induced rapid extra-nuclear signaling. Conversely, new evidence suggests that androgen actions may also be mediated through epigenetic modulation involving both the nuclear and extra-nuclear androgen signaling. This review focuses on androgen-induced epigenetic modifications in female reproduction, specifically in the ovary, and discusses emerging concepts, latest perceptions, and highlight the areas that need further investigation.

Multiomics Analysis Reveals Molecular Abnormalities in Granulosa Cells of Women With Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the most common complex endocrine and metabolic disease in women of reproductive age. It is characterized by anovulatory infertility, hormone disorders, and polycystic ovarian morphology. Regarding the importance of granulosa cells (GCs) in the pathogenesis of PCOS, few studies have investigated the etiology at a single “omics” level, such as with an mRNA expression array or methylation profiling assay, but this can provide only limited insights into the biological mechanisms. Here, genome-wide DNA methylation together with lncRNA-miRNA-mRNA profiles were simultaneously detected in GCs of PCOS cases and controls. A total of 3579 lncRNAs, 49 miRNAs, 669 mRNAs, and 890 differentially methylated regions (DMR)-associated genes were differentially expressed between PCOS cases and controls. Pathway analysis indicated that these differentially expressed genes were commonly associated with steroid biosynthesis and metabolism-related signaling, such as glycolysis/gluconeogenesis. In addition, we constructed ceRNA networks and identified some known ceRNA axes, such as lncRNAs-miR-628-5p-CYP11A1/HSD17B7. We also identified many new ceRNA axes, such as lncRNAs-miR-483-5p-GOT2. Interestingly, most ceRNA axes were also closely related to steroid biosynthesis and metabolic pathways. These findings suggest that it is important to systematically consider the role of reproductive and metabolic genes in the pathogenesis of PCOS.

Elevated ovarian pentraxin 3 in polycystic ovary syndrome

PURPOSE

Pentraxin 3 (PTX3) plays a crucial role in cumulus expansion and fertilization. The ovarian PTX3 level in polycystic ovary syndrome (PCOS) remains uncertain. In the present study, we investigated the follicular PTX3 levels and found the influence of reproductive hormones on ovarian PTX3 concentration.

METHODS

This study was based on 204 healthy-weight women (102 PCOS and 102 normal ovulating subjects) undergoing in vitro fertilization (IVF). Follicular fluid (FF) was collected during oocyte retrieval. The PTX3 levels and other hormone levels in FF samples were analyzed by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The PTX3 level in the follicle was significantly higher in the healthy-weight PCOS women than controls. Positive correlations were found between ovarian PTX3 level and the existence of PCOS, cycle length, basal LH to FSH ratio and TT in serum, antral follicle count, and ovarian insulin and androgen level, and inverse correlations with the basal serum PRL and ovarian SHBG. In multivariant linear regression analysis, the presence of PCOS diagnosis, participants' basal LH to FSH ratio, and ovarian androstenedione level were the main predictors of ovarian PTX3 level among the enrolled subjects.

CONCLUSION

Elevated ovarian PTX3 level supports the low-grade chronic inflammatory state in the follicles of PCOS. The existence of PCOS, disturbed pituitary gland, and ovarian hyperandrogenism might also be related to this state of low-grade chronic inflammation and could be a subject of further study.

Role of Lipid Metabolism and Signaling in Mammalian Oocyte Maturation, Quality, and Acquisition of Competence

It has been found that the quality of oocytes from obese women has been compromised and subsequent embryos displayed arrested development. The compromised quality may be either due to the poor or rich metabolic conditions such as imbalance or excession of lipids during oocyte development. Generally, lipids are mainly stored in the form of lipid droplets and are an important source of energy metabolism. Similarly, lipids are also essential signaling molecules involved in various biological cascades of oocyte maturation, growth and oocyte competence acquisition. To understand the role of lipids in controlling the oocyte development, we have comprehensively and concisely reviewed the literature and described the role of lipid metabolism in oocyte quality and maturation. Moreover, we have also presented a simplified model of fatty acid metabolism along with its implication on determining the oocyte quality and cryopreservation for fertilization.

Polycystic ovary syndrome is transmitted via a transgenerational epigenetic process

Polycystic ovary syndrome (PCOS) is the most common reproductive and metabolic disorder affecting women of reproductive age. PCOS has a strong heritable component, but its pathogenesis has been unclear. Here, we performed RNA sequencing and genome-wide DNA methylation profiling of ovarian tissue from control and third-generation PCOS-like mice. We found that DNA hypomethylation regulates key genes associated with PCOS and that several of the differentially methylated genes are also altered in blood samples from women with PCOS compared with healthy controls. Based on this insight, we treated the PCOS mouse model with the methyl group donor S-adenosylmethionine and found that it corrected their transcriptomic, neuroendocrine, and metabolic defects. These findings show that the transmission of PCOS traits to future generations occurs via an altered landscape of DNA methylation and propose methylome markers as a possible diagnostic landmark for the condition, while also identifying potential candidates for epigenetic-based therapy.

Polycystic Ovarian Syndrome Genetics and Epigenetics

Polycystic ovarian syndrome and its associated endocrine abnormalities comprise one of the most common metabolic spectrum disorders within the human race. Because of the variance in phenotypic expression among individuals and within family lineages, attention has been turned to genetic and epigenetic changes in which the root cause of the disorder may lie. Further understanding of DNA/histone methylation and microRNA patterns may help to improve the accuracy of diagnosis and lead to future treatment options.

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.

lnc-MAP3K13-7:1 Inhibits Ovarian GC Proliferation in PCOS via DNMT1 Downregulation-Mediated CDKN1A Promoter Hypomethylation

Polycystic ovary syndrome (PCOS) is an endocrine-related disease and global cause of infertility that is associated with abnormal folliculogenesis. Inhibited granulosa cell (GC) proliferation is recognized as a key factor that underlies aberrant follicle maturation. Many epigenetic landscape modifications have been characterized in PCOS patients. However, the epigenetic regulation pathways in follicular dysplasia are not completely understood. In this study, we reported a novel mechanism of DNA hypomethylation induced by long non-coding RNAs (lncRNAs) and its function in cell cycle progression. We observed that lnc-MAP3K13-7:1 was highly expressed in GCs from patients with PCOS, with concomitant global DNA hypomethylation, decreased DNA methyltransferase 1 (DNMT1) expression, and increased cyclin-dependent kinase inhibitor 1A (CDKN1A, p21) expression. In KGN cells, lnc-MAP3K13-7:1 overexpression resulted in cell cycle arrest in the G₀/G₁ phase, as well as the molecular inhibition and genetic silencing of DNMT1. Mechanistically, lnc-MAP3K13-7:1 inhibited DNMT1 expression by acting as a protein-binding scaffold and inducing ubiquitin-mediated DNMT1 protein degradation. Moreover, DNMT1-dependent CDKN1A promoter hypomethylation increased CDKN1A transcription, resulting in attenuated GC growth. Our work uncovered a novel and essential mechanism through which lnc-MAP3K13-7:1-dependent DNMT1 inhibition regulates CDKN1A/p21 expression and inhibits GC proliferation.

D-Chiro-Inositol Treatment Affects Oocyte and Embryo Quality and Improves Glucose Intolerance in Both Aged Mice and Mouse Models of Polycystic Ovarian Syndrome

Polycystic ovarian syndrome (PCOS) is the main cause of female infertility. It is a multifactorial disorder with varying clinical manifestations including metabolic/endocrine abnormalities, hyperandrogenism, and ovarian cysts, among other conditions. D-Chiro-inositol (DCI) is the main treatment available for PCOS in humans. To address some of the mechanisms of this complex disorder and its treatment, this study examines the effect of DCI on reproduction during the development of different PCOS-associated phenotypes in aged females and two mouse models of PCOS. Aged females (8 months old) were treated or not (control) with DCI for 2 months. PCOS models were generated by treatment with dihydrotestosterone (DHT) on Days 16, 17, and 18 of gestation, or by testosterone propionate (TP) treatment on the first day of life. At two months of age, PCOS mice were treated with DCI for 2 months and their reproductive parameters analyzed. No effects of DCI treatment were produced on body weight or ovary/body weight ratio. However, treatment reduced the number of follicles with an atretic cyst-like appearance and improved embryo development in the PCOS models, and also increased implantation rates in both aged and PCOS mice. DCI modified the expression of genes related to oocyte quality, oxidative stress, and luteal sufficiency in cumulus-oocyte complexes (COCs) obtained from the aged and PCOS models. Further, the phosphorylation of AKT, a main metabolic sensor activated by insulin in the liver, was enhanced only in the DHT group, which was the only PCOS model showing glucose intolerance and AKT dephosphorylation. The effect of DCI in the TP model seemed mediated by its influence on oxidative stress and follicle insufficiency. Our results indicate that DCI works in preclinical models of PCOS and offer insight into its mechanism of action when used to treat this infertility-associated syndrome.

Key Relevance of Epigenetic Programming of Adiponectin Gene in Pathogenesis of Metabolic Disorders

Background & Objective::

Significant health and social burdens have been created by the growth of metabolic disorders like type 2 diabetes mellitus (T2DM), atherosclerosis, and non-alcoholic steatohepatitis, worldwide. The number of the affected population is as yet rising, and it is assessed that until 2030, 4−5 million individuals will acquire diabetes. A blend of environmental, genetic, epigenetic, and other factors, such as diet, are accountable for the initiation and progression of metabolic disorders. Several researches have shown strong relevance of adiponectin gene and metabolic disorders. In this review, the potential influence of epigenetic mechanisms of adiponectin gene “ADIPOQ” on increasing the risk of developing metabolic disorders and their potential in treating this major disorder are discussed.

Results & Conclusion::

Various studies have postulated that a series of factors such as maternal High fat diet (HFD), oxidative stress, pro-inflammatory mediators, sleep fragmentation throughout lifetime, from gestation to old age, could accumulate epigenetic marks, including histone remodeling, DNA methylation, and microRNAs (miRNAs) that, in turn, alter the expression of ADIPOQ gene and result in hypoadiponectinemia which precipitates insulin resistance (IR) that in turn might induce or accelerate the onset and development of metabolic disorder. A better understanding of global patterns of epigenetic modifications and further their alterations in metabolic disorders will bestow better treatment strategies design.