Identification of epigenetic interactions between microRNA and DNA methylation associated with polycystic ovarian syndrome

Semaphorin 3E-Plexin-D1 Pathway Downstream of the Luteinizing Hormone Surge Regulates Ovulation, Granulosa Cell Luteinization, and Ovarian Angiogenesis in Mice

Ovulation is induced by the luteinizing hormone (LH) surge and accompanied by granulosa cell luteinization and ovarian angiogenesis. Semaphorin 3E (Sema3E)-Plexin-D1 pathway regulates angiogenesis in other tissues, but its role in the ovary is unknown. Evidence indicates that Sema3E-Plexin-D1 pathway plays an important role in the mouse ovary. The expression of Sema3E and its receptor, Plexin-D1, is dynamically regulated in the mouse ovary downstream of the LH surge. This regulation requires the modulation of chromatin accessibility by CCAAT/enhancer-binding proteins α and β. Intraovarian injection of recombinant Sema3E results in reduced ovulation, impaired corpus luteum formation, and aberrant ovarian angiogenesis. These in vivo physiological abnormalities are consistent with altered expression of genes regulating these processes, and with data from in vitro cultured granulosa cells and ovarian stromal tissues treated with Sema3E or neutralizing antibody of Plexin-D1. The findings pinpoint Sema3E-Plexin-D1 pathway as a potential therapeutic target for fertility and infertility management.

The regulatory interplay between miRNA and DNA methylation orchestrates vital ovarian functions and associated traits in PCOS

Polycystic ovary syndrome (PCOS) is the leading cause of amenorrhea and anovulatory infertility in women of reproductive age. Both gene polymorphisms and tissue-specific epigenetic alterations, which determine gene transcription and translation dynamics in disease-states, strongly influence PCOS development. Particularly, promoter-proximal DNA methylation and microRNA expression changes show strong associations with follicular defects, suggesting post-transcriptional dysregulation of localized gene networks. Our recent methylome study and other studies, posit DNA methylation as a regulator of microRNA expression in PCOS. Here, we identified microRNAs, potentially regulated by DNA methylation, and investigated whether their altered expression influences target gene expression in the PCOS ovary. Using granulosa cell samples of women with PCOS and age-BMI matched controls, we evaluated the transcript levels of 14 microRNAs participating in different ovarian processes and assessed their CpG-DNA methylation levels. For 9 of these microRNAs, which revealed differential methylation consistent with their gene hypomethylation or hypermethylation profiles, we evaluated the expression of their predicted, proteincoding target transcripts. Our data indicated that microRNA hypermethylation and decreased transcription of miR-10b-5p, miR-127-3p, miR-5189, miR-410-3p and miR23a-3p were consistent with the upregulation of PTEN, MMP13, OLR1, TET3 and APAF1 in PCOS. Conversely, microRNA hypomethylation and increased expression of miR-140-5p, miR-182-3p, miR-200b-5p and miR-3687 were consistent with downregulation of FZD6, LRP6, ZEB1 and LDLR. However, these observations need robust validations in larger study cohorts complemented with functional and mechanistic studies. Overall, our study indicates that altered microRNA expression as a consequence of DNA methylation changes, may contribute to metabolic and reproductive dysfunction in PCOS.

Integrated multi-omics analysis reveals complement component 3 as a central driver of immune dysregulation in polycystic ovary syndrome

Background

Polycystic Ovary Syndrome (PCOS) is a prevalent endocrine disorder with a complex pathophysiology, affecting various aspects of women's health. Despite its widespread impact, the molecular basis and immunological aspects of PCOS remain insufficiently understood, limiting effective diagnosis and treatment strategies.

Objective

This study aims to elucidate the molecular and immunological landscape of PCOS by integrating gene expression profiles from healthy and PCOS-affected ovaries using both bulk and single-cell omics data, with the goal of constructing a comprehensive bioinformatics network that identifies potential biomarkers and therapeutic targets.

Methods

Leveraging publicly available omics datasets, we compared gene expression between healthy ovaries and those affected by PCOS through both bulk and single-cell analyses. Our approach focused on differential gene expression analysis, identification of distinct cell types and gene signatures in PCOS, construction of disease-specific gene expression modules, and mapping of cellular differentiation trajectories. Additionally, we examined the alterations in the immune microenvironment within PCOS to identify immune-related changes.

Results

Our analyses uncovered unique molecular signatures and immune modules in PCOS, characterized by differential gene expression, the presence of unique cell types, and altered pathways compared to healthy controls. Notably, we identified a significant role for Complement Component 3 (C3) in mediating these changes. Through gene intervention targeting C3 in granulosa cells and functional studies examining the effects of secreted C3 protein on H295R cells, Low level C3 mitigated inflammatory responses, while excess C3 proved detrimental to cell growth.

Conclusion

Our integrative omics analysis provides new insights into the molecular and immunological underpinnings of PCOS, highlighting the role of C3 in the disease's pathogenesis. The identification of key molecular signatures and immune modules, including the involvement of C3, opens promising avenues for the development of novel diagnostic and therapeutic strategies for PCOS. These observations suggest that modulating C3 levels could have therapeutic implications for managing PCOS.

Identification of molecular characteristics in polycystic ovary syndrome using single-cell and transcriptome analysis

Polycystic Ovary Syndrome (PCOS) is a complex endocrine disorder affecting women of childbearing age, and we aimed to reveal its underlying molecular mechanisms. Gene expression profiles from GSE138518 and GSE155489, and single-cell RNA sequencing (scRNA-seq) data from PRJNA600740 were collected and subjected to bioinformatics analysis to identify the complex molecular mechanisms of PCOS. The expression of genes was detected by RT-qPCR. Through differential analysis, we identified 230 common differentially expressed genes (DEGs) in GSE138518 and GSE155489. GSEA results showed significant enrichment of purine metabolism and oocyte meiosis in the control group, while GSVA results indicated significant activation of ECM receptor interaction, and antigen processing and presentation in PCOS. Weighted gene co-expression network analysis revealed 7 co-expression modules, with the bisque4 module showing the highest positive correlation with PCOS. Enrichment analysis revealed that genes in the bisque4 module were mainly involved in the PI3K-Akt signaling pathway, calcium signaling pathway, and Ras signaling pathway. Pseudotime trajectory analysis of cell subpopulations revealed the potential developmental trajectory of PCOS. The gene expression consistent with the potential developmental trajectory was validated by RT-qPCR. Our study, by analyzing multiple datasets, has revealed the complex molecular network of PCOS, offering new insights into understanding its pathophysiological basis.

Development of an Endoplasmic Reticulum Stress-Related Diagnostic Signature in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder in premenopausal women. This investigation was to elucidate the underlying mechanism of endoplasmic reticulum stress (ERS) activation in granulosa cells, which has been implicated in the etiology of PCOS. Differentially expressed genes (DEGs) between PCOS and control groups were integrated with ERS gene lists from databases to identify DE-ERS genes, and functional analyses were performed. Univariate regression analysis and the LASSO method were used to select diagnostic factors, followed by establishing a DE-ERS gene-based diagnostic model. A nomogram model was further generated to predict the risk of PCOS. The correlation between ERS gene expression and immune cell proportion was assessed. A total of 14 DE-ERS genes associated with "protein processing in endoplasmic reticulum", "ferroptosis", and "glycerophospholipid metabolism" were selected as PCOS-related factors. An eight-DE-ERS genes-based diagnostic model was developed and displayed satisfactory performance in the training (Area under curve (AUC) = 0.983) and validation datasets (AUC = 0.802). High risk of PCOS can be accurately predicted, which might contribute to clinical decision-making. Moreover, EDEM1 expression was significantly positively correlated with naive B cell infiltration, while PDIA6 was negatively correlated with neutrophil proportion (P < 0.001). We identified eight novel molecules and developed an ERS gene-based diagnostic model in PCOS, which might provide novel insight for finding biomarkers and treatment methods.

The landscape of alternative splicing in granulosa cells and a potential novel role of YAP1 in PCOS

Polycystic ovary syndrome (PCOS) is a prevalent yet complex reproductive endocrine disorder affecting 11-13% of women worldwide. Its main symptoms include elevated androgen levels, irregular menstrual cycles, and long-term metabolic and offspring health implications. Despite the disease's multifaceted nature involving genetic, epigenetic, and environmental factors, the role of alternative splicing in ovarian granulosa cells remains relatively unexplored. This study aims to investigate the transcriptional and alternative splicing characteristics of granulosa cells in PCOS patients and to elucidate the potential functional consequences of these changes. Analysis of previous published transcriptome sequencing data identified 491 upregulated and 401 downregulated genes in granulosa cells of PCOS patients, significantly involved in immune-related processes. Additionally, 1250 differential splicing events, predominantly involving exon skipping and affecting 947 genes, were detected. These genes with alternative splicing patterns were found to be enriched in endoplasmic reticulum stress and protein post-translational modification processes, suggesting their role in PCOS pathology. Moreover, the study highlighted that the utilization of different splice isoforms of the YAP1 gene may impact its interaction in the Hippo signaling pathway, influencing the pathogenesis of PCOS. These findings underscore substantial alterations in alternative splicing in granulosa cells of PCOS patients, providing a novel viewpoint for comprehending the molecular underpinnings of PCOS and suggesting potential avenues for therapeutic intervention.

Exploring the therapeutic mechanisms of Yikang decoction in polycystic ovary syndrome: an integration of GEO datasets, network pharmacology, and molecular dynamics simulations

Objective

The incidence of Polycystic Ovary Syndrome (PCOS) is increasing annually. This study aims to investigate the therapeutic mechanisms of Yikang Decoction (YKD) in the treatment of PCOS through the integration of GEO datasets, network pharmacology, and dynamic simulation.

Methods

Active ingredients of YKD and their targets were collected from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) platform. Disease-relevant targets for PCOS were retrieved from several databases, including GeneCards, OMIM, PharmGKB, DrugBank, and GEO. The underlying pathways associated with the overlapping targets between YKD and PCOS were identified using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The mechanisms of interaction between the core targets and components were further explored through molecular docking and molecular dynamics simulations (MD).

Results

139 potential active components and 315 targets of YKD were identified. A topological analysis of the PPI network revealed 10 core targets. These targets primarily participated in the regulation of biological processes, including cell metabolism, apoptosis, and cell proliferation. The pathways associated with treating PCOS encompassed PI3K-Akt signaling pathway, Lipid and atherosclerosis, MAPK signaling pathways, and Endocrine resistance signaling pathways. Moreover, molecular docking and MD have been shown to reveal a good binding capacity between active compounds and screening targets.

Conclusion

This study systematically investigates the multi-target mechanisms of YKD in the treatment of PCOS, with preliminary verification provided through molecular docking and MD. The findings offer compelling evidence supporting the efficacy of YKD in treating PCOS.

Interleukin-1 increases SERPINE1 expression in human granulosa-lutein cell via P50/P52 signaling pathways

It has been reported that immune factors are associated with the occurrence of polycystic ovary syndrome (PCOS). Interleukin-1 (IL-1) is a member of the interleukin family that widely participates in the regulation of the inflammatory response in the immune system. In addition, it has been reported that aberrant IL-1 accumulation in serum is associated with the occurrence of PCOS. However, little is known about how IL-1 participates in the pathogenesis of PCOS. In the present study, we demonstrated that the immune microenvironment was altered in follicular fluid from PCOS patients and that the expression levels of two IL-1 cytokines, IL-1α and IL-1β were increased. Transcriptome analysis revealed that IL-1α and IL-1β treatment induced primary human granulosa-lutein (hGL) cell inflammatory response and increased the expression of serpin family E member 1 (SERPINE1). Mechanistically, we demonstrated that IL-1α and IL-1β upregulated SERPINE1 expression through IL-1R1-mediated activation of downstream P50 and P52 signaling pathways in human granulosa cells. Our study highlighted the role of immune state changes in the occurrence of PCOS and provided new insight into the treatment of patients with IL-1-induced ovarian function disorders.

Transcriptome profiling reveals dysregulation of inflammatory and protein synthesis genes in PCOS

To analyze the differential expression genes of polycystic ovary syndrome (PCOS), clarify their functions and pathways, as well as the protein-protein interaction network, identify HUB genes, and explore the pathological mechanism. PCOS microarray datasets were screened from the GEO database. Common differentially expressed genes (co-DEGs) were obtained using GEO2R and Venn analysis. Enrichment and pathway analyses were conducted using the DAVID online tool, with results presented in bubble charts. Protein-protein interaction analysis was performed using the STRING tool. HUB genes were identified using Cytoscape software and further interpreted with the assistance of the GeneCards database. A total of two sets of co-DEGs (108 and 102), key proteins (15 and 55), and hub genes (10 and 10) were obtained. The co-DEGs: (1) regulated inflammatory responses and extracellular matrix, TNF, and IL-17 signaling pathways; (2) regulated ribosomes and protein translation, ribosome and immune pathways. The key proteins: (1) regulated inflammation, immunity, transcription, matrix metabolism, proliferation/differentiation, energy, and repair; (2) regulated ubiquitination, enzymes, companion proteins, respiratory chain components, and fusion proteins. The Hub genes: (1) encoded transcription factors and cytokines, playing vital roles in development and proliferation; (2) encoded ribosomes and protein synthesis, influencing hormone and protein synthesis, associated with development and infertility. The dysregulated expression of inflammation and protein synthesis genes in PCOS may be the key mechanism underlying its onset and progression.

Genetic and Epigenetic Landscape for Drug Development in Polycystic Ovary Syndrome

The treatment of polycystic ovary syndrome (PCOS) faces challenges as all known treatments are merely symptomatic. The US Food and Drug Administration has not approved any drug specifically for treating PCOS. As the significance of genetics and epigenetics rises in drug development, their pivotal insights have greatly enhanced the efficacy and success of drug target discovery and validation, offering promise for guiding the advancement of PCOS treatments. In this context, we outline the genetic and epigenetic advancement in PCOS, which provide novel insights into the pathogenesis of this complex disease. We also delve into the prospective method for harnessing genetic and epigenetic strategies to identify potential drug targets and ensure target safety. Additionally, we shed light on the preliminary evidence and distinctive challenges associated with gene and epigenetic therapies in the context of PCOS.

Dysregulated RNA editing of EIF2AK2 in polycystic ovary syndrome: clinical relevance and functional implications

BACKGROUND

Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder affecting women of reproductive ages. Our previous study has implicated a possible link between RNA editing and PCOS, yet the actual role of RNA editing, its association with clinical features, and the underlying mechanisms remain unclear.

METHODS

Ten RNA-Seq datasets containing 269 samples of multiple tissue types, including granulosa cells, T helper cells, placenta, oocyte, endometrial stromal cells, endometrium, and adipose tissues, were retrieved from public databases. Peripheral blood samples were collected from twelve PCOS and ten controls and subjected to RNA-Seq. Transcriptome-wide RNA-Seq data analysis was conducted to identify differential RNA editing (DRE) between PCOS and controls. The functional significance of DRE was evaluated by luciferase reporter assays and overexpression in human HEK293T cells. Dehydroepiandrosterone and lipopolysaccharide were used to stimulate human KGN granulosa cells to evaluate gene expression.

RESULTS

RNA editing dysregulations across multiple tissues were found to be associated with PCOS in public datasets. Peripheral blood transcriptome analysis revealed 798 DRE events associated with PCOS. Through weighted gene co-expression network analysis, our results revealed a set of hub DRE events in PCOS blood. A DRE event in the eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2:chr2:37,100,559) was associated with PCOS clinical features such as luteinizing hormone (LH) and the ratio of LH over follicle-stimulating hormone. Luciferase assays, overexpression, and knockout of RNA editing enzyme adenosine deaminase RNA specific (ADAR) showed that the ADAR-mediated editing cis-regulated EIF2AK2 expression. EIAF2AK2 showed a higher expression after dehydroepiandrosterone and lipopolysaccharide stimulation, triggering changes in the downstrean MAPK pathway.

CONCLUSIONS

Our study presented the first evidence of cross-tissue RNA editing dysregulation in PCOS and its clinical associations. The dysregulation of RNA editing mediated by ADAR and the disrupted target EIF2AK2 may contribute to PCOS development via the MPAK pathway, underlining such epigenetic mechanisms in the disease.

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.

CAPN2 correlates with insulin resistance states in PCOS as evidenced by multi-dataset analysis

OBJECTIVE

IR emerges as a feature in the pathophysiology of PCOS, precipitating ovulatory anomalies and endometrial dysfunctions that contribute to the infertility challenges characteristic of this condition. Despite its clinical significance, a consensus on the precise mechanisms by which IR exacerbates PCOS is still lacking. This study aims to harness bioinformatics tools to unearth key IR-associated genes in PCOS patients, providing a platform for future therapeutic research and potential intervention strategies.

METHODS

We retrieved 4 datasets detailing PCOS from the GEO, and sourced IRGs from the MSigDB. We applied WGCNA to identify gene modules linked to insulin resistance, utilizing IR scores as a phenotypic marker. Gene refinement was executed through the LASSO, SVM, and Boruta feature selection algorithms. qPCR was carried out on selected samples to confirm findings. We predicted both miRNA and lncRNA targets using the ENCORI database, which facilitated the construction of a ceRNA network. Lastly, a drug-target network was derived from the CTD.

RESULTS

Thirteen genes related to insulin resistance in PCOS were identified via WGCNA analysis. LASSO, SVM, and Boruta algorithms further isolated CAPN2 as a notably upregulated gene, corroborated by biological verification. The ceRNA network involving lncRNA XIST and hsa-miR-433-3p indicated a possible regulatory link with CAPN2, supported by ENCORI database. Drug prediction analysis uncovered seven pharmacological agents, most being significant regulators of the endocrine system, as potential candidates for addressing insulin resistance in PCOS.

CONCLUSIONS

This study highlights the pivotal role of CAPN2 in insulin resistance within the context of PCOS, emphasizing its importance as both a critical biomarker and a potential therapeutic target. By identifying CAPN2, our research contributes to the expanding evidence surrounding the CAPN family, particularly CAPN10, in insulin resistance studies beyond PCOS. This work enriches our understanding of the mechanisms underlying insulin resistance, offering insights that bridge gaps in the current scientific landscape.

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.

Deconvolution at the single-cell level reveals ovarian cell-type-specific transcriptomic changes in PCOS

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most common reproductive endocrine disorders in females of childbearing age. Various types of ovarian cells work together to maintain normal reproductive function, whose discordance often takes part in the development and progression of PCOS. Understanding the cellular heterogeneity and compositions of ovarian cells would provide insight into PCOS pathogenesis, but are, however, not well understood. Transcriptomic characterization of cells isolated from PCOS cases have been assessed using bulk RNA-seq but cells isolated contain a mixture of many ovarian cell types.

METHODS

Here we utilized the reference scRNA-seq data from human adult ovaries to deconvolute and estimate cell proportions and dysfunction of ovarian cells in PCOS, by integrating various granulosa cells(GCs) transcriptomic data.

RESULTS

We successfully defined 22 distinct cell clusters of human ovarian cells. Then after transcriptome integration, we obtained a gene expression matrix with 13,904 genes within 30 samples (15 control vs. 15 PCOS). Subsequent deconvolution analysis revealed decreased proportion of small antral GCs and increased proportion of KRT8high mural GCs, HTRA1high cumulus cells in PCOS, especially increased differentiation from small antral GCs to KRT8high mural GCs. For theca cells, the abundance of internal theca cells (TCs) and external TCs was both increased. Less TCF21high stroma cells (SCs) and more STARhigh SCs were observed. The proportions of NK cells and monocytes were decreased, and T cells occupied more in PCOS and communicated stronger with inTCs and exTCs. In the end, we predicted the candidate drugs which could be used to correct the proportion of ovarian cells in patients with PCOS.

CONCLUSIONS

Taken together, this study provides insights into the molecular alterations and cellular compositions in PCOS ovarian tissue. The findings might contribute to our understanding of PCOS pathophysiology and offer resource for PCOS basic research.

High levels of fatty acid-binding protein 5 excessively enhances fatty acid synthesis and proliferation of granulosa cells in polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is one of the most complex endocrine disorders in women of reproductive age. Abnormal proliferation of granulosa cells (GCs) is an important cause of PCOS. This study aimed to explore the role of fatty acid-binding protein 5 (FABP5) in granulosa cell (GC) proliferation in polycystic ovary syndrome (PCOS) patients.

METHODS

The FABP5 gene, which is related to lipid metabolism, was identified through data analysis of the gene expression profiles of GSE138518 from the Gene Expression Omnibus (GEO) database. The expression levels of FABP5 were measured by quantitative real-time PCR (qRT‒PCR) and western blotting. Cell proliferation was evaluated with a cell counting kit-8 (CCK-8) assay. Western blotting was used to assess the expression of the proliferation marker PCNA, and immunofluorescence microscopy was used to detect Ki67 expression. Moreover, lipid droplet formation was detected with Nile red staining, and qRT‒PCR was used to analyze fatty acid storage-related gene expression.

RESULTS

We found that FABP5 was upregulated in ovarian GCs obtained from PCOS patients and PCOS mice. FABP5 knockdown suppressed lipid droplet formation and proliferation in a human granulosa-like tumor cell line (KGN), whereas FABP5 overexpression significantly enhanced lipid droplet formation and KGN cell proliferation. Moreover, we determined that FABP5 knockdown inhibited PI3K-AKT signaling by suppressing AKT phosphorylation and that FABP5 overexpression activated PI3K-AKT signaling by facilitating AKT phosphorylation. Finally, we used the PI3K-AKT signaling pathway inhibitor LY294002 and found that the facilitation of KGN cell proliferation and lipid droplet formation induced by FABP5 overexpression was inhibited. In contrast, the PI3K-AKT signaling pathway agonist SC79 significantly rescued the suppression of KGN cell proliferation and lipid droplet formation caused by FABP5 knockdown.

CONCLUSIONS

FABP5 promotes active fatty acid synthesis and excessive proliferation of GCs by activating PI3K-AKT signaling, suggesting that abnormally high expression of FABP5 in GCs may be a novel biomarker or a research target for PCOS treatment.

A novel nanoprobe for visually investigating the controversial role of miRNA-34a as an oncogene or tumor suppressor in cancer cells

MiRNA-targeted therapy has become a hot topic in current cancer research. The key to this treatment strategy is to clarify the specific role of miRNA in cancer. However, the roles of some miRNAs acting as oncogenic or tumor suppressors are still controversial, which are influenced by different tumor types, even in the same cancer type. Hence, we designed a novel fluorescent nanoprobe based on polydopamine nanoparticles (PDA NPs) for simultaneously detecting caspase-3 and miRNA-34a within living cells. The specific role of miRNA-34a in different cancer cells could be further identified by studying the expression alterations of caspase-3 and miRNA-34a. Confocal imaging indicated that miRNA-34a indeed acted as a tumor suppressor in anticancer drug-treated MCF-7 and HeLa cells, where the effect of miRNA-34a remains controversial. The designed nanoprobe can offer a promising approach to ascertain the oncogenic or tumor-suppressing role of miRNA in different cancer cells with a simple visualization method, which has valuable implications for exploring the practicability of precision therapy focused on miRNA and evaluating the efficacy of new miRNA-targeted anticancer medications.

Identification and validation of senescence-related genes in polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is an exceedingly intractable issue affecting female endocrine and reproductive health. However, the etiology and intricate pathological mechanisms of PCOS remain unclear. Nowadays, aging was found to share multiple common pathological mechanisms with PCOS, which causes probing into the pathogenesis of PCOS from senescence. However, no bioinformatics analyses have specifically focused on connection between PCOS and ovarian aging.

METHODS

Differentially expressed aging-related genes in PCOS were identified and then analyzed using function enrichment method. Hub genes were determined based on multiple algorithms, and expression validation of hub genes was performed in both datasets and experiments (human granulosa-like tumor cell line, KGN; human Granulosa Cell, hGCs). Finally, a transcription factor-miRNA-gene network of hub genes was constructed.

RESULTS

Here, we identified 73 aging-related differential expression genes (ARDEGs) by intersecting DEGs in PCOS and senescence-related gene set. Furthermore, we performed biological functions and potential pathways of ARDEGs and potential hub genes were also screened by multiple algorithms. From the perspective of immune dysfunction, we analyzed the correlation between PCOS and immune cells. Finally, TF-miRNA-gene networks were constructed. Finally, TF-miRNA-gene networks were constructed.

CONCLUSIONS

Our work aimed to elucidate the relation between PCOS and cellular senescence based on bioinformatics strategy, deepening the understanding of mechanisms and to seek for novel therapy strategies for improving reproductive lifespan and female health. Exploring the potential molecular mechanism of cell aging in PCOS is expected to bring a new breakthrough for PCOS diagnosis and therapy strategies. And this, might deepen our understanding about intricate mechanisms of ovarian aging.

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.

Significance of LHCGR polymorphisms in polycystic ovary syndrome: an association study

This study was conducted to analyze the association of Luteinizing Hormone/Choriogonadotropin Receptor (LHCGR) gene rs4953616 and rs7371084 polymorphisms with the risk of polycystic ovary syndrome (PCOS) in Punjab, India. A total of 823 women (443 PCOS cases and 380 healthy controls) were enrolled in the present study. The polymerase chain reaction-restriction fragment length polymorphism technique (PCR-RFLP) was used for genotyping. Anthropometric parameters, lipid and hormonal profiles, were compared between the two groups. Demographic features were compared using Mann Whitney U test while the Chi-square test and odds ratios (ORs) were used to assess the genetic association and risk towards PCOS, respectively. A one-way analysis of variance (ANOVA) test was employed to analyze the correlation of genotypes with baseline parameters in PCOS cases. A statistically significant difference was revealed in the genotypic and allelic frequencies of rs4953616 polymorphism between PCOS cases and controls (p = 0.01 and p = 0.004, respectively). The mutant genotype (TT), mutant allele (T), and recessive model of rs4953616 polymorphism conferred 1.77, 1.3, and 1.5 times risk towards PCOS, respectively. No significant distribution for genotypes and alleles was found for rs7371084 in both groups (p = 0.25 and p = 0.26, respectively). In addition to dyslipidemia, PCOS women also had significantly higher body mass index (BMI) and waist-to-hip ratio (WHR), testosterone (T), and luteinizing hormone (LH). Upon haplotype analysis, the TT haplotype was found to be significantly associated with the increased risk of PCOS. Our results demonstrated a significant role of LHCGR rs4953616 polymorphism in the development of PCOS.

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.

Transcriptomic profile of GLCs of PCOS women highlights metabolic dysregulation as a plausible contributor to PCOS pathophysiology

Polycystic ovary syndrome (PCOS) is a complex heterogeneous disorder with reproductive and metabolic consequences whose aetiology is still elusive. To understand the cellular mechanisms that potentially govern follicular defect in women with PCOS, we performed transcriptomic profiles of granulosa-lutein cells (GLCs) by RNA-Seq analysis. We found differential expression of 876 genes in GLCs between PCOS and controls that belonged to various processes such as cell cycle, extracellular matrix organization, angiogenesis, oxidative stress, metabolism, etc. that support folliculogenesis, oocyte development, and maturation. The cross-talk between oocyte and GLCs is a fundamental cornerstone in determining oocyte quality and highly interlinked pathways of metabolism and redox homeostasis may influence this. We found several genes involved in the metabolism of carbohydrates, nucleotides, cholesterol, and lipids were dysregulated, which may impair the supply of metabolites to the growing oocyte, affecting oocyte development and competence. Additionally, high metabolic activity during folliculogenesis may augment oxidative damage to cells and macromolecules if not counter-balanced. We observed dysregulation of redox homeostasis and AGE-RAGE signalling in the follicular environment. Among the validated genes, prokineticin-1 and growth differentiation factor-15 were found to be negatively regulated, while, S100, calcium-binding protein A9 and angiomotin-like-2 were positively regulated in GLCs of women with PCOS. Comparing our data with previously published relevant transcriptomic studies showed metabolic, cytokine-cytokine receptor interaction, IL-17, and chemokine signalling pathways were most commonly affected in PCOS. Overall, this data can provide insights into mechanisms contributing to PCOS pathophysiology and can be explored as potential indicators for oocyte/embryo quality in IVF settings.

Hepatic and ovarian effects of perfluorooctanoic acid exposure differ in lean and obese adult female mice

Obesity and overweight cause poor oocyte quality, miscarriage, infertility, polycystic ovarian syndrome, and offspring birth defects and affects 40% and 20% of US women and girls, respectively. Perfluorooctanoic acid (PFOA), a per- and poly-fluoroalkyl substance (PFAS), is environmentally persistent and has negative female reproductive effects including endocrine disruption, oxidative stress, altered menstrual cyclicity, and decreased fertility in humans and animal models. PFAS exposure is associated with non-alcoholic fatty liver disease which affects ∼24-26% of the US population. This study investigated the hypothesis that PFOA exposure impacts hepatic and ovarian chemical biotransformation and alters the serum metabolome. At 7 weeks of age, female lean, wild type (KK.Cg-a/a) or obese (KK.Cg-Ay/J) mice received saline (C) or PFOA (2.5 mg/Kg) per os for 15 d. Hepatic weight was increased by PFOA exposure in both lean and obese mice (P < 0.05) and obesity also increased liver weight (P < 0.05) compared to lean mice. The serum metabolome was also altered (P < 0.05) by PFOA exposure and differed between lean and obese mice. Exposure to PFOA altered (P < 0.05) the abundance of ovarian proteins with roles in xenobiotic biotransformation (lean - 6; obese - 17), metabolism of fatty acids (lean - 3; obese - 9), cholesterol (lean - 8; obese - 11), amino acids (lean - 18; obese - 19), glucose (lean - 7; obese - 10), apoptosis (lean - 18; obese - 13), and oxidative stress (lean - 3; obese - 2). Use of qRT-PCR determined that exposure to PFOA increased (P < 0.05) hepatic Ces1 and Chst1 in lean but Ephx1 and Gstm3 in obese mice. Also, obesity basally increased (P < 0.05) Nat2, Gpi and Hsd17b2 mRNA levels. These data identify molecular changes resultant from PFOA exposure that may cause liver injury and ovotoxicity in females. In addition, differences in toxicity induced by PFOA exposure occurs in lean and obese mice.

Transcriptome analysis identification of A-to-I RNA editing in granulosa cells associated with PCOS

Background

Polycystic ovary syndrome (PCOS) is a complex, multifactor disorder in women of reproductive age worldwide. Although RNA editing may contribute to a variety of diseases, its role in PCOS remains unclear.

Methods

A discovery RNA-Seq dataset was obtained from the NCBI Gene Expression Omnibus database of granulosa cells from women with PCOS and women without PCOS (controls). A validation RNA-Seq dataset downloaded from the European Nucleotide Archive Databank was used to validate differential editing. Transcriptome-wide investigation was conducted to analyze adenosine-to-inosine (A-to-I) RNA editing in PCOS and control samples.

Results

A total of 17,395 high-confidence A-to-I RNA editing sites were identified in 3,644 genes in all GC samples. As for differential RNA editing, there were 545 differential RNA editing (DRE) sites in 259 genes with Nucleoporin 43 (NUP43), Retinoblastoma Binding Protein 4 (RBBP4), and leckstrin homology-like domain family A member 1 (PHLDA) showing the most significant three 3'-untranslated region (3'UTR) editing. Furthermore, we identified 20 DRE sites that demonstrated a significant correlation between editing levels and gene expression levels. Notably, MIR193b-365a Host Gene (MIR193BHG) and Hook Microtubule Tethering Protein 3 (HOOK3) exhibited significant differential expression between PCOS and controls. Functional enrichment analysis showed that these 259 differentially edited genes were mainly related to apoptosis and necroptosis pathways. RNA binding protein (RBP) analysis revealed that RNA Binding Motif Protein 45 (RBM45) was predicted as the most frequent RBP binding with RNA editing sites. Additionally, we observed a correlation between editing levels of differential editing sites and the expression level of the RNA editing enzyme Adenosine Deaminase RNA Specific B1 (ADARB1). Moreover, the existence of 55 common differentially edited genes and nine differential editing sites were confirmed in the validation dataset.

Conclusion

Our current study highlighted the potential role of RNA editing in the pathophysiology of PCOS as an epigenetic process. These findings could provide valuable insights into the development of more targeted and effective treatment options for PCOS.

Transcriptome Profiling of Goose Ovarian Follicle Granulosa Cells Reveals Key Regulatory Networks for Follicle Selection

The selection of follicles determines the reproductive performance of birds, but the process of follicle selection in geese is still elusive. This study focuses on Yangzhou geese during the egg-laying period and divides the follicular development process into three stages: small follicle development, follicle selection, and follicle maturation. Transcriptome sequencing was performed on granulosa cells from large white follicles, small yellow follicles, and F5 and F4 follicles. In addition, we selected the transcripts that remained unchanged during the development and maturation of small follicles but significantly changed during the follicular selection stage as the transcript collection that plays an important role in the follicular selection process. Then, we performed functional analysis on these transcripts and constructed a ceRNA network. The results showed that during the follicular selection stage, the number of differentially expressed mRNAs, miRNAs, and lncRNAs was the highest. In addition, miR-222-3p, miR-2954-3p, miR-126-5p, miR-2478, and miR-425-5p are potential key core regulatory molecules in the selection stage of goose follicles. These results can provide a reference for a better understanding of the basic mechanisms of the goose follicle selection process and potential targets for the precise regulation of goose egg production performance.

Obesity and PCOS radically alters the snRNA composition of follicular fluid extracellular vesicles

Introduction

The ovarian follicle consists of the oocyte, somatic cells, and follicular fluid (FF). Proper signalling between these compartments is required for optimal folliculogenesis. The association between polycystic ovarian syndrome (PCOS) and extracellular vesicular small non-coding RNAs (snRNAs) signatures in follicular fluid (FF) and how this relates to adiposity is unknown. The purpose of this study was to determine whether FF extracellular vesicle (FFEV)-derived snRNAs are differentially expressed (DE) between PCOS and non-PCOS subjects; and if these differences are vesicle-specific and/or adiposity-dependent.

Methods

FF and granulosa cells (GC) were collected from 35 patients matched by demographic and stimulation parameters. FFEVs were isolated and snRNA libraries were constructed, sequenced, and analyzed.

Results

miRNAs were the most abundant biotype present, with specific enrichment in exosomes (EX), whereas in GCs long non-coding RNAs were the most abundant biotype. In obese PCOS vs. lean PCOS, pathway analysis revealed target genes involved in cell survival and apoptosis, leukocyte differentiation and migration, JAK/STAT, and MAPK signalling. In obese PCOS FFEVs were selectively enriched (FFEVs vs. GCs) for miRNAs targeting p53 signalling, cell survival and apoptosis, FOXO, Hippo, TNF, and MAPK signalling.

Discussion

We provide comprehensive profiling of snRNAs in FFEVs and GCs of PCOS and non-PCOS patients, highlighting the effect of adiposity on these findings. We hypothesize that the selective packaging and release of miRNAs specifically targeting anti-apoptotic genes into the FF may be an attempt by the follicle to reduce the apoptotic pressure of the GCs and stave off premature apoptosis of the follicle observed in PCOS.

MMDAE-HGSOC: A novel method for high-grade serous ovarian cancer molecular subtypes classification based on multi-modal deep autoencoder

High-grade serous ovarian cancer (HGSOC) is a type of ovarian cancer developed from serous tubal intraepithelial carcinoma. The intrinsic differences among molecular subtypes are closely associated with prognosis and pathological characteristics. At present, multi-omics data integration methods include early integration and late integration. Most existing HGSOC molecular subtypes classification methods are based on the early integration of multi-omics data. The mutual interference among multi-omics data is ignored, which affects the effectiveness of feature learning. High-dimensional multi-omics data contains genes unassociated with HGSOC molecular subtypes, resulting in redundant information, which is not conducive to model training. In this paper, we propose a multi-modal deep autoencoder learning method, MMDAE-HGSOC. MiRNA expression, DNA methylation, and copy number variation (CNV) are integrated with mRNA expression data to construct a multi-omics feature space. The multi-modal deep autoencoder network is used to learn the high-level feature representation of multi-omics data. The superposition LASSO (S-LASSO) regression algorithm is proposed to fully obtain the associated genes of HGSOC molecular subtypes. The experimental results show that MMDAE-HGSOC is superior to the existing classification methods. Finally, we analyze the enrichment gene ontology (GO) terms and biological pathways of these significant genes, which are discovered during the gene selection process.

Multiomics Analysis-Based Biomarkers in Diagnosis of Polycystic Ovary Syndrome

Polycystic ovarian syndrome is an utmost communal endocrine, psychological, reproductive, and metabolic disorder that occurs in women of reproductive age with extensive range of clinical manifestations. This may even lead to long-term multiple morbidities including obesity, diabetes mellitus, insulin resistance, cardiovascular disease, infertility, cerebrovascular diseases, and ovarian and endometrial cancer. Women affliction from PCOS in midst assemblage of manifestations allied with menstrual dysfunction and androgen exorbitance, which considerably affects eminence of life. PCOS is recognized as a multifactorial disorder and systemic syndrome in first-degree family members; therefore, the etiology of PCOS syndrome has not been copiously interpreted. The disorder of PCOS comprehends numerous allied health conditions and has influenced various metabolic processes. Due to multifaceted pathophysiology engaging several pathways and proteins, single genetic diagnostic tests cannot be supportive to determine in straight way. Clarification of cellular and biochemical pathways and various genetic players underlying PCOS could upsurge our consideration of pathophysiology of this syndrome. It is requisite to know pathophysiological relationship between biomarker and their reflection towards PCOS disease. Biomarkers deliver vibrantly and potent ways to apprehend the spectrum of PCOS with applications in screening, diagnosis, characterization, and monitoring. This paper relies on the endeavor to point out many candidates as potential biomarkers based on omics technologies, thus highlighting correlation between PCOS disease with innovative technologies. Therefore, the objective of existing review is to encapsulate more findings towards cutting-edge advances in prospective use of biomarkers for PCOS disease. Discussed biomarkers may be fruitful in guiding therapies, addressing disease risk, and predicting clinical outcomes in future.

Integrated bioinformatics analysis and screening of hub genes in polycystic ovary syndrome

PURPOSE

Polycystic ovary syndrome (PCOS) is one of the most common endocrine and metabolic disorders, posing a serious threat to the health of women. Herein, we aimed to explore new biomarkers and potential therapeutic targets for PCOS by employing integrated bioinformatics tools.

METHODS

Three gene expression profile datasets (GSE138518, GSE155489, GSE106724) were obtained from the Gene Expression Omnibus database and the differentially expressed genes in PCOS and normal groups with an adjusted p-value &lt; 0.05 and a |log fold change (FC) | &gt; 1.2 were first identified using the DESeq package. The weighted correlation network analysis (WGCNA) R package was used to identify clusters of highly correlated genes or modules associated with PCOS. Protein-protein interaction (PPI) network analysis and visualization of genes in the key module were performed using the STRINGdb database and the NetworkX package (edge &gt; 5), respectively. The genes overlapping among the key module genes and PCOS-associated genes were further analyzed. Ligand molecules with strong binding energy &lt; -10 kJ/mol to GNB3 were screened in the drug library using MTiOpenScreen. AutoDock, ChimeraX, and BIOVIA Discovery Studio Visualizer were further used to elucidate the mechanism of ligand interaction with GNB3. Finally, the relationship between GNB3 and PCOS was verified using experimental models in vivo and in vitro.

RESULTS

Of the 11 modules identified by WGCNA, the black module had the highest correlation with PCOS (correlation = 0.96, P = 0.00016). The PPI network of 351 related genes revealed that VCL, GNB3, MYH11, LMNA, MLLT4, EZH2, PAK3, and CHRM1 have important roles in PCOS. The hub gene GNB3 was identified by taking the intersection of PCOS-related gene sets. MTiOpenScreen revealed that five compounds interacted with GNB3. Of these five, compound 1 had the strongest binding ability and can bind amino acids in the WD40 motif of GNB3, which in turn affects the function of the G protein-coupled receptor β subunit. GNB3 was also significantly downregulated in PCOS models.

CONCLUSION

We identified the hub gene GNB3 as the most important regulatory gene in PCOS. We suggest that compound 1 can target the WD40 motif of GNB3 to affect related functions and must be considered as a lead compound for drug development. This study will provide new insights into the development of PCOS-related drugs.

Long noncoding RNA NEAT1 decreases polycystic ovary syndrome progression via the modulation of the microRNA-324-3p and BRD3 axis

Long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) is believed to be involved in many gynecological and obstetrics disorders. Nevertheless, the role of NEAT1 in polycystic ovary syndrome (PCOS) is scarcely investigated. Our study aimed to investigate the role of NEAT1, microRNA (miR)-324-3p, and bromodomain containing 3 (BRD3) in PCOS. First, 80 women with PCOS and 80 healthy (non-PCOS) women were included, and their serum hormone levels were tested. Next, the PCOS mouse model was established by dehydroepiandrosterone injection, and then NEAT1, miR-324-3p, and BRD3 expression levels were detected in the PCOS mice. Lentivirus carrying short hairpin-NEAT1 or miR-324-3p agomir was injected into the PCOS mice to determine the change in biochemical indices and pathology. Moreover, a rescue experiment was conducted, after which, the binding relationships among NEAT1, miR-324-3p, and BRD3 were analyzed. NEAT1 and BRD3 were expressed at a high level while miR-324-3p was expressed at a low level in women with PCOS and PCOS mice. Reduced levels of NEAT1 or elevated levels of miR-324-3p mitigated metabolic disorders and alleviated ovarian pathological changes in PCOS mice. Mechanistically, NEAT1 sponged miR-324-3p and miR-324-3p targeted BRD3. In the rescue experiment, elevated miR-324-3p or reduced BRD3 level reversed the effects of the enhanced NEAT1 on metabolic disorders and ovarian pathological changes in PCOS mice. NEAT1 exacerbates metabolic disorders and ovarian pathological changes in PCOS mice by downregulating miR-324-3p and upregulating BRD3. This study gives a novel direction in PCOS treatment.

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.

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.

MicroRNAs as Biomarkers for Early Diagnosis, Prognosis, and Therapeutic Targeting of Ovarian Cancer

Ovarian cancer is the major cause of gynecologic cancer-related mortality. Regardless of outstanding advances, which have been made for improving the prognosis, diagnosis, and treatment of ovarian cancer, the majority of the patients will die of the disease. Late-stage diagnosis and the occurrence of recurrent cancer after treatment are the most important causes of the high mortality rate observed in ovarian cancer patients. Unraveling the molecular mechanisms involved in the pathogenesis of ovarian cancer may help find new biomarkers and therapeutic targets for ovarian cancer. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression, mostly at the posttranscriptional stage, through binding to mRNA targets and inducing translational repression or degradation of target via the RNA-induced silencing complex. Over the last two decades, the role of miRNAs in the pathogenesis of various human cancers, including ovarian cancer, has been documented in multiple studies. Consequently, these small RNAs could be considered as reliable markers for prognosis and early diagnosis. Furthermore, given the function of miRNAs in various cellular pathways, including cell survival and differentiation, targeting miRNAs could be an interesting approach for the treatment of human cancers. Here, we review our current understanding of the most updated role of the important dysregulation of miRNAs and their roles in the progression and metastasis of ovarian cancer. Furthermore, we meticulously discuss the significance of miRNAs as prognostic and diagnostic markers. Lastly, we mention the opportunities and the efforts made for targeting ovarian cancer through inhibition and/or stimulation of the miRNAs.

Identification of Three Potential circRNA Biomarkers of Polycystic Ovary Syndrome by Bioinformatics Analysis and Validation

Objective

It is well known that circRNAs are closely involved in the progression of various diseases. However, their functions and potential regulatory mechanisms in polycystic ovary syndrome (PCOS) remain largely unknown. In the present study, our aim was to investigate the potential diagnostic value of circRNAs in PCOS.

Methods

The circRNA dataset GSE145296, mRNA dataset GSE155489 and miRNA GSE138572 were downloaded from Gene Expression Omnibus (GEO) database. Then, differentially expressed genes (DEGs) were identified. Based on the potential interactions, a network of cirRNA-related competing endogenous RNAs (ceRNAs) was constructed. Biological functions were predicted by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. For further validation, qRT-PCR method was used to detect the expression level of the candidate circRNAs. Then, receiver operating characteristics (ROC) were constructed to evaluate the diagnostic value of the three differentially expressed circRNA (DE-circRNA).

Results

We constructed a network of cirRNA-related ceRNA network. Hsa_circ_0075691, hsa_circ_0075692 and hsa_circ_0085997 were validate to be dysregulated in PCOS.

Conclusion

Hsa_circ_0075691, hsa_circ_0075692 and hsa_circ_0085997 may be potential diagnostic biomarkers of PCOS, but their specific regulatory mechanisms still need to be further studied.

Circular RNA circ_RANBP9 exacerbates polycystic ovary syndrome via microRNA-136-5p/XIAP axis

Polycystic ovary syndrome (PCOS) is an endocrine disease that affects the health of many women. Circular RNAs (circRNAs) are associated with the occurrence and progression of PCOS. This study aimed to explore the function of circ_RANBP9 in PCOS. First, the circ_RANBP9 level was found to be increased in the plasma of patients with PCOS and ovarian granulosa cells (GCs) using Reverse Transcription-Quantitative Polymerase Chain Reaction (RT-qPCR). In GCs, loss of circ_RANBP9 decelerated proliferation and accelerated apoptosis of KGN and COV434 cells, as determined by MTT assay, colony formation assay, and flow cytometry. Furthermore, bioinformatics analysis showed that circ_RANBP9 and XIAP can be targeted by the microRNA, miR-136-5p. Luciferase reporter assay and RNA pull-down assay further verified the interaction between miR-136-5p and circ_RANBP9 or XIAP. Importantly, knockdown of circ_RANBP9 suppressed proliferation and promoted apoptosis of KGN and COV434 cells, whereas inhibition of miR-136-5p reversed these effects. Additionally, XIAP abolished the repression of proliferation and acceleration of apoptosis induced by miR-136-5p. The promotion of apoptosis was accompanied by upregulation of caspase-3 and Bax, and downregulation of Bcl-2, as estimated by western blotting. In conclusion, silencing of circ_RANBP9 inhibited GC proliferation and facilitated apoptosis by mediating the miR-136-5p/XIAP pathway. These findings provide a new theoretical basis for screening and treatment of PCOS.

Aberrant miRNA-mRNA regulatory network in polycystic ovary syndrome is associated with markers of insulin sensitivity and inflammation

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common multifactorial metabolic and endocrine disorder in women of reproductive age. Increasingly, evidence indicates that the microRNA (miRNA)-mRNA axis contributes to the development of PCOS.

METHODS

To investigate the molecular mechanisms through which miRNA-mRNA expression affects hyperandrogenism, ovarian tissue samples from prenatally androgenized (PNA) mice were subjected to miRNA-seq and RNA-seq analysis. Analyses were performed to identify differentially expressed microRNAs (DEmiRs) and differentially expressed genes (DEGs). In combination with our previous data obtained from clinical samples, we have performed an integrated miRNA-mRNA analysis of PNA mice and granulosa cells (GCs) from patients with PCOS. The changes in expression were validated by RT-qPCR in more mouse models and clinical samples.

RESULTS

In total, 3,432 genes and 16 miRNAs were differentially expressed in PNA mice compared with the control mice. We investigated the regulation pattern of miRNAs-mRNAs and observed a total of 12 miRNA-mRNA pairs involved in negative regulation. Functional analysis concentrated on insulin resistance, the T cell receptor signaling pathway, and other inflammation-related pathways. Verification of these results by RT-qPCR showed that the expression of miR-106-5p and miR-155-5p in clinical GCs was consistent with that in PNA mice. After predicting the target genes of miR-106-5p and miR-155-5p and performing negative regulation analysis, six target genes were obtained in GCs. The integration analysis showed that the network of miR-106-5p/miR-155-5p targets was mostly concentrated in pathway related to insulin resistance and inflammation. In addition, the upregulation of the inflammatory genes Il18/IL18 and Socs3/SOCS3 was validated in the PNA mice and GCs from patients compared with the appropriate control sample. The in vitro experiments showed that the regulatory relationship observed may be related to the direct stimulation of DHT.

CONCLUSIONS

Our results showed that the miRNA-mRNA regulatory network in PCOS was associated with markers of insulin sensitivity and inflammation. Our study provides a new genetic basis and novel insight regarding the pathogenesis of PCOS.

A review on the DNA methyltransferase family of insects: Aspect and prospects

The DNA methyltransferase family contains a conserved set of DNA-modifying enzymatic proteins. They are responsible for epigenetic gene modulation, such as transcriptional silencing, transcription activation, and post-transcriptional modulation. Recent research has revealed that the canonical DNA methyltransferases (DNMTs) biological roles go beyond their traditional functions of establishing and maintaining DNA methylation patterns. Although a complete DNA methylation toolkit is absent in most insect orders, recent evidence indicates the de novo DNA methylation and maintenance function remain conserved. Studies using various molecular approaches provided evidence that DNMTs are multi-functional proteins. However, still in-depth studies on their biological role lack due to the least studied area in insects. Here, we review the DNA methylation toolkit of insects, focusing on recent research on various insect orders, which exhibit DNA methylation at different levels, and for which DNMTs functional studies have become available in recent years. We survey research on the potential roles of DNMTs in the regulation of gene transcription in insect species. DNMTs participate in different physiological processes by interacting with other epigenetic factors. Future studies on insect's DNMTs will benefit to understand developmental processes, responses to various stimuli, and adaptability of insects to different environmental conditions.

Characterization of micro-RNA in women with different ovarian reserve

Women undergoing infertility treatment are routinely subjected to one or more tests of ovarian reserve. Therefore, an adequate assessment of the ovarian reserve is necessary for the treatment. In this study, we aimed to characterize the potential role of microRNAs (miRNAs) as biomarkers for women with different ovarian reserves. A total of 159 women were recruited in the study and classified according to their anti-Müllerian hormone (AMH) level into three groups: (1) low ovarian reserve (LAMH, n = 39), (2) normal ovarian reserve (NAMH, n = 80), and (3) high ovarian reserve (HAMH, n = 40). SurePrint Human miRNA array screening and reverse transcription-quantitative PCR (RT-qPCR) were respectively employed to screen and validate the miRNA abundance level in the three tested groups. Compared with NAMH, the abundance level of 34 and 98 miRNAs was found to be significantly altered in LAMH and HAMH, respectively. The abundance level of miRNAs was further validated by RT-qPCR in both, the screening samples as well as in an independent set of validation samples. The abundance levels of the validated miRNAs were significantly correlated with the AMH level. The best AUC value for the prediction of the increase and decrease in the AMH level was obtained for the miR-100-5p and miR-21-5p, respectively. The level of miRNAs abundance correlates with the level of AMH, which may serve as a tool for identifying women with a different ovarian reserve and may help to lay the ground for the development of novel diagnostic approaches.

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.

Characterization of DNA Methylation and Screening of Epigenetic Markers in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine and metabolic disorder in women, which is characterized by androgen excess, ovulation dysfunction, and polycystic ovary. Although the etiology of PCOS is largely unknown, many studies suggest that aberrant DNA methylation is an important contributing factor for its pathological changes. In this study, we investigated DNA methylation characteristics and their impact on gene expression in granulosa cells obtained from PCOS patients. Transcriptome analysis found that differentially expressed genes were mainly enriched in pathways of insulin resistance, fat cell differentiation, and steroid metabolism in PCOS. Overall DNA methylation level in granulosa cells was reduced in PCOS, and the first introns were found to be the major genomic regions that were hypomethylated in PCOS. Integrated analysis of transcriptome, DNA methylation, and miRNAs in ovarian granulosa cells revealed a DNA methylation and miRNA coregulated network and identified key candidate genes for pathogenesis of PCOS, including BMP4, ETS1, and IRS1. Our study shed more light on epigenetic mechanism of PCOS and provided valuable reference for its diagnosis and treatment.

PCOS follicular fluid derived exosomal miR-424-5p induces granulosa cells senescence by targeting CDCA4 expression

Polycystic ovary syndrome (PCOS) is a heterogeneous reproductive disease, characterized by increased ovarian androgen biosynthesis, chronic anovulation and polycystic ovaries. The objective of this study was to identify the altered miRNA expression profiles in follicular fluid derived exosomes isolated from PCOS patients and to investigate the molecular functions of exosomal miR-424-5p. Herein, small RNA sequencing showed that twenty-five miRNAs were differentially expressed between control and PCOS group. The alterations in the miRNA profile were related to the endocrine resistance, cell growth and proliferation, cellular senescence and insulin signaling pathway. Among these differentially expressed miRNAs, we found that the expression of miR-424-5p was significantly decreased in PCOS exosomes and primary granulosa cells (GCs). Exosome-enriched miR-424-5p significantly promoted GCs senescence and suppressed cell proliferation. Similar to the results obtained in the cells transfected with miR-424-5p mimic, miR-424-5p mimic significantly decreased cell proliferation ability and induced senescence, but treatment with miR-424-5p inhibitor got the opposite results. In addition, cell division cycle associated 4 (CDCA4) gene displayed an inverse expression pattern to those of miR-424-5p, was identified as the direct target of miR-424-5p. Overexpression of CDCA4 reversed the effects of exosomal miR-424-5p on GCs via activation of Rb/E2F1 signaling pathway. These results demonstrate that exosomal miR-424-5p inhibits GCs proliferation and induces cellular senescence in PCOS through blocking CDCA4-mediated Rb/E2F1 signaling. Our findings provide new information on abnormal follicular development in PCOS.

miR-141-3p is Poorly Expressed in Polycystic Ovary Syndrome and Correlates with Glucose and Lipid Metabolism

Polycystic ovary syndrome (PCOS) is a common endocrinopathy with high prevalence. miR-141-3p downregulation was reported in PCOS rats. This study intended to investigate miR-141-3p expression in serum of PCOS patients and its correlation with glucose and lipid metabolism. A total of 100 PCOS patients and 100 healthy controls were enrolled in this study. Clinical parameters and glucose and lipid indexes were analyzed. A 3-month fat reduction intervention was conducted to PCOS-obese patients. Expressions of miR-141-3p and PTEN were detected. WHR and levels of TG, HDL-C, FBG, FINS, HOMA-β, and HOMA-IR showed significant differences in PCOS patients. miR-141-3p was downregulated in PCOS patients. Area under ROC curve of miR-141-3p diagnosing PCOS-obese patients was 0.985 with specificity 95.35% and flexibility 93.33%. Levels of glucose and lipid metabolism indexes were increased while HDL-C level was decreased in miR-141-3p low expression group. Indexes of PCOS-obese patients were improved and miR-141-3p was upregulated after fat reduction intervention. PTEN was upregulated in PCOS patients and negatively correlated with miR-141-3p. In conclusion, miR-141-3p was downregulated in PCOS patients and had higher diagnostic value on PCOS and associated with glucose and lipid metabolism. miR-141-3p might play a role in glucose and lipid metabolism in PCOS-obese patients by targeting PTEN.

Polycystic Ovary Syndrome: A Brain Disorder Characterized by Eating Problems Originating during Puberty and Adolescence

Polycystic ovary syndrome (PCOS) is an endocrine condition associated with reproductive and psychiatric disorders, and with obesity. Eating disorders, such as bulimia and recurrent dieting, are also linked to PCOS. They can lead to the epigenetic dysregulation of the hypothalamic-pituitary-gonadal (HPG) axis, thereby impacting on ovarian folliculogenesis. We postulate that PCOS is induced by psychological distress and episodes of overeating and/or dieting during puberty and adolescence, when body dissatisfaction and emotional distress are often present. We propose that upregulated activation of the central HPG axis during this period can be epigenetically altered by psychological stressors and by bulimia/recurrent dieting, which are common during adolescence and which can lead to PCOS. This hypothesis is based on events that occur during a largely neglected stage of female reproductive development. To date, most research into the origins of PCOS has focused on the prenatal induction of this disorder, particularly in utero androgenization and the role of anti-Müllerian hormone. Establishing causality in our peripubertal model requires prospective cohort studies from infancy. Mechanistic studies should consider the role of the gut microbiota in addition to the epigenetic regulation of (neuro) hormones. Finally, clinicians should consider the importance of underlying chronic psychological distress and eating disorders in PCOS.