The Role of microRNAs in Ovarian Granulosa Cells in Health and Disease

Unseen toxins: Exploring the human health consequences of micro and nanoplastics

Micro and nanoplastics (MNPs) contamination constitute a pressing global issue with considerable ramifications for human health. Particles originating from the decomposition of plastic waste permeate ecosystems and disturb biological systems, especially the gastrointestinal (GI) tract. MNPs compromise the intestinal barrier, provoke oxidative stress, inflammation, and immunological dysfunction, and modify gut microbiota, which is associated with metabolic problems, inflammatory bowel disease (IBD), and colorectal cancer. MNPs traverse biological barriers beyond the gastrointestinal system, including the blood-brain barrier, colonic mucus layer, and placental barrier, resulting in accumulation in essential organs such as the liver, kidneys, and brain. This results in inflammatory damage, metabolic abnormalities, and oxidative stress, specifically affecting liver disease due to microbiota metabolite alteration and nephrotoxicity in the kidneys. Airborne MNPs pose an additional risk to respiratory health, aggravating ailments such as asthma, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis. At-risk groups, such as pregnant women, newborns, and the elderly, encounter increased dangers, as MNPs traverse the placental barrier and may induce neurological and intergenerational health consequences. These particles function as vectors for environmental pollutants, exacerbating their cardiovascular and neurological effects. Addressing the long-term consequences of MNP exposure necessitates interdisciplinary collaboration to enhance comprehension and alleviate their growing risk to human health.

The Role of Ovarian Granulosa Cells Related-ncRNAs in Ovarian Dysfunctions: Mechanism Research and Clinical Exploration

Ovarian dysfunctions, encompassing conditions such as polycystic ovary syndrome (PCOS), premature ovarian failure (POF), premature ovarian insufficiency (POI), and diminished ovarian reserve (DOR), are closely linked to disruptions in follicular development, often tied to granulosa cell (GC) abnormalities. Despite ongoing research, the precise mechanisms underlying these dysfunctions remain elusive. Increasing evidence highlights the pivotal role of non-coding RNAs (ncRNAs) in the pathogenesis of ovarian dysfunctions. As transcripts that do not encode proteins, ncRNAs are capable of regulating gene expression at various levels. They influence GCs by modulating key biological processes including proliferation, apoptosis, autophagy, cell cycle progression, steroidogenesis, mitochondrial function, inflammatory responses, and aging. Disruptions in GC development and function can lead to impaired follicular development, consequently contributing to ovarian dysfunctions. Thus, ncRNAs are likely integral to the regulatory mechanisms underlying these pathologies, exhibiting distinct expression patterns in affected individuals. This review delves into the regulatory roles of ncRNAs in GCs and their implications for ovarian dysfunctions (PCOS, POF, POI, DOR), offering insights into potential biomarkers for ovarian function assessment and novel therapeutic approaches for treating these conditions.

Dr. Jekyll or Mr. Hyde: The multifaceted roles of miR-145-5p in human health and disease

MicroRNAs (miRNAs) are classified as small, non-coding RNAs that play crucial roles in diverse biological processes, including cellular development, differentiation, growth, and metabolism. MiRNAs regulate gene expression by recognizing complementary sequences within messenger RNA (mRNA) molecules. Recent studies have revealed that miR-145-5p functions as a tumor suppressor in several cancers, including lung, liver, and breast cancers. Notably, miR-145-5p plays a vital role in the pathophysiology underlying HIV and chronic obstructive pulmonary diseases associated with cigarette smoke. This miRNA is abundant in biofluids and shows potential as a biomarker for the diagnosis and prognosis of several infectious diseases, such as hepatitis B, tuberculosis, and influenza. Additionally, numerous studies have indicated that other non-coding RNAs, including long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), can regulate miR-145-5p. Given the significance of miR-145-5p, a comprehensive overview focusing on its roles in health and disease is essential. This review discusses the dual role of miR-145-5p as a protagonist and antagonist in important human diseases, with particular emphasis on disorders of the respiratory, digestive, nervous, reproductive, endocrine, and urinary systems.

Beyond Repetition: The Role of Gray Zone Alleles in the Upregulation of FMR1-Binding miR-323a-3p and the Modification of BMP/SMAD-Pathway Gene Expression in Human Granulosa Cells

The Fragile X mental retardation type 1 gene (FMR1) contains a CGG triplet cluster of varied length (30 repeats on average) located in its 5' UTR. In its premutated state (54-200 repeats), FMR1 contributes to the pathogenesis of premature ovarian insufficiency (POI). Its gray zone alleles (41-54 repeats) are supposed to impair the ovarian function as well. In the case of a CGG repeat length > 200, Fragile X syndrome occurs. Post-transcriptional expression of FMR1 is regulated by microRNAs. Although miR-323a-3p overexpression suppresses FMR1 in various tissues, this relationship has not been evaluated in the human ovary. Additionally, this microRNA targets SMADs, which are suggested regulators of ovarian cell proliferation, growth, and function. This study investigated how FMR1 allele lengths with CGG repeat numbers n < 55 (normal and gray zone genotypes) relate to miR-323a-3p expression and how they may impact associated SMAD expression in human granulosa cells. COV434 cells and patient-derived GCs were used to evaluate FMR1, miR-323a-3p, and BMP/SMAD-pathway member expression levels. Briefly, miR-323a-3p was significantly upregulated in GCs of the gray zone group compared to the normal allele group (p < 0.0001), while the FMR1 level did not vary. Furthermore, the gray zone group showed a significant upregulation of BMPR2, SMAD1, SMAD4, and SMAD9. In contrast, the miR-323a-3p transfection of COV434 cells significantly downregulated SMAD3, SMAD4, SMAD5, and SMAD9, while the FMR1 and SMAD1 levels remained stable. Our findings highlight a CGG repeat number-dependent upregulation of miR-323a-3p and an alteration of the BMP/SMAD pathway, suggesting that these changes happen and contribute to impaired ovarian function independently.

Apoptosis in polycystic ovary syndrome: Mechanisms and therapeutic implications

Polycystic ovary syndrome (PCOS) is a common disorder that affects the female reproductive system, with an incidence of 8 % to 15 %. It is characterized by irregular menstruation, hyperandrogenemia, and polycystic abnormalities in the ovaries. Nevertheless, there is still much to learn about the molecular pathways underlying PCOS. Apoptosis is the process by which cells actively destroy themselves, and it is vital to an organism's ability to develop normally and maintain homeostasis. In recent years, a growing body of research has indicated a connection between the pathophysiology of PCOS and apoptosis. Therefore, it is critical to comprehend the relationship between PCOS and apoptosis in greater detail, identify the pathophysiological underpinnings of PCOS, and provide fresh perspectives and targets for its treatment. This review aims to summarize the relationship between PCOS and apoptosis, discuss how apoptosis affects normal ovarian function and how it becomes dysfunctional in the ovaries of PCOS patients, and investigate the signaling pathways associated with apoptosis in PCOS, including PI3K-Akt, TNF, NF-κB, and p53. Additionally, potential therapeutic approaches for PCOS treatment are provided by summarizing the role of apoptosis in PCOS therapy.

LncRNA-THBS4 affects granulosa cell proliferation and apoptosis in diminished ovarian reserve by regulating PI3K/AKT/mTOR signaling pathway

BACKGROUNDS

Recent studies have found Several lncRNAs were proved differential expression in diminished ovarian reserve (DOR) patients, however, the mechanism of DOR caused by lncRNAs is still largely unclear.

METHODS

High throughput sequencing was performed in ovarian GCs extracted from women with normal ovarian function and women with DOR. Bioinformation analysis was used to analyze the sequencing data and identify the differential expression of lncRNAs. Quantitative RT-PCR (qRT-PCR) was used to verify the sequencing results. Situ fluorescence hybridization (FISH) followed by confocal microscopy and qRT-PCR were used to explore the location and expression of LncRNA-THBS4 in GCs. The significantly enriched signaling pathways of LncRNA-THBS4 were identified by KEGG. The study used RNA interference technology to decipher LncRNA-THBS4 function by silencing LncRNA-THBS4 in GCs. Western blot and qRT-PCR were used to explore the mRNA and protein expressions of key factors of PI3Ks pathway. The pro-apoptotic protein and anti-apoptotic protein were detected by western blot. The proliferation and apoptosis of GCs were detected by MTT assay and Flow cytometry.

RESULTS

197 lncRNAs with significant differences in expression levels were detected between control and DOR group by high throughput sequencing. The study found the expression of LncRNA-THBS4 in GCs was positively correlated with Anti-Mullerian hormone (AMH) (p = 0.0020, r = 0.4742)、antral follicle count (AFC) (p = 0.0007, r = 0.5130)、good embryo rate (p = 0.0006, r = 0.5210), negatively correlated with basal FSH level (p = 0.0007, r = －0.5152). LncRNA-THBS4 was mainly localized in the cytoplasm of GCs. LncRNA-THBS4 silencing could inhibit the PI3Ks pathway; decrease the levels of anti-apoptotic protein, inhibit the proliferation of GCs; increase the levels of apoptosis protein, enhance the apoptosis of GCs.

CONCLUSIONS

The expression level of lncRNA-THBS4 is correlated with ovarian function indicators and pregnancy outcomes in women. LncRNA-THBS4 may participate in the pathogenesis of DOR by affecting the proliferation and apoptosis of GCs via regulating PI3K/AKT/mTOR signaling pathway.

NOX4 deficiency improves the impaired viability, inhibited the apoptosis and suppressed autophagy of DHEA-treated ovarian granulosa cells through inhibiting endoplasmic reticulum stress via inactivating PERK/ATF4 pathway

BACKGROUND

PCOS is the most prevalent endocrine and metabolic problem in women of reproductive age. This current study was formulated to thoroughly expound the ovary-protecting effects of NOX4 deficiency in PCOS and probe into the intrinsic mechanisms underlying the protective effects of NOX4 deficiency against DHEA injury in ovarian GCs.

METHODS

KGN cells were subjected to 20 nM DHEA for 48 h to establish PCOS cellular model. For loss-of-function experiments, KGN cells were transfected with si-NOX4. In addition, to investigate the biological roles of ERS and PERK/ATF4 pathway in the ovary-protecting effects of NOX4 deficiency in DHEA-treated ovarian GCs, KGN cells were pretreated with ERS agonist TM or PERK agonist CCT020312.

RESULTS

NOX4 was highly expressed in DHEA-treated ovarian GCs. NOX4 deficiency improved the impaired viability, inhibited the apoptosis and suppressed autophagy of DHEA-treated ovarian GCs. Besides, NOX4 deficiency inactivated PERK/ATF4 pathway in DHEA-treated ovarian GCs. NOX4 deficiency repressed DHEA-induced ERS of ovarian GCs through inactivating PERK/ATF4 pathway. Pretreatment with ERS agonist TM or pretreatment with PERK agonist CCT020312 can both reduced the viability, promoted the apoptosis and strengthened autophagy of ovarian GCs, partially abolishing the ovary-protecting effects of NOX4 deficiency in DHEA-treated ovarian GCs. In general, NOX4 deficiency could improve the impaired viability, inhibited the apoptosis and suppressed autophagy of DHEA-treated ovarian GCs through repressing ERS depending on inactivation of PERK/ATF4 pathway.

CONCLUSION

To conclude, downregulation of NOX4 could exert ovary-protecting effects in DHEA-induced PCOS cellular model through repressing ERS via inactivating PERK/ATF4 pathway.

Study on the effects of Mogroside V in inhibiting NLRP3-mediated granulosa cell pyroptosis and insulin resistance to improve PCOS

OBJECTIVE

Polycystic Ovary Syndrome (PCOS) is a prevalent endocrinopathy in reproductive-aged women, contributing to 75% of infertility cases due to ovulatory dysfunction. The condition poses significant health and psychological challenges, making the study of its pathogenesis and treatment a research priority. This study investigates the effects of Mogroside V (MV) on PCOS, focusing on its anti-inflammatory and anti-insulin resistance properties.

METHODS

Forty-five female Sprague-Dawley rats were divided into three groups: control, PCOS model, and MV treatment. The PCOS model was induced using a high-fat diet and letrozole. The MV treatment group was subsequently administered MV after the establishment of the PCOS model. The study monitored body mass, assessed estrous cycle changes, and measured serum hormone levels. Transcriptome sequencing and bioinformatics were used to identify differentially expressed genes related to inflammation and insulin resistance. Expression of pyroptosis and insulin resistance markers was analyzed using qRT-PCR, Western blot, and IHC. Additionally, an in vitro model assessed MV's impact on inflammation and insulin resistance.

RESULTS

The PCOS group exhibited elevated serum testosterone (T), luteinizing hormone (LH), insulin, and fasting glucose levels, along with increased insulin resistance (HOMA-IR) and decreased estradiol (E2), which were reversed by MV treatment. Transcriptome analysis identified significant gene expression changes between groups, particularly in pathways related to NLRP3 inflammation and insulin metabolism. MV treatment normalized the expression of ovarian pyroptosis factors (NLRP3, Caspase-1, GSDMD) and inflammatory cytokines (IL-1β, IL-18). In cellular models, MV increased E2 levels, reduced LDH release, and decreased the expression of insulin resistance and pyroptosis markers. Correlation analysis showed pyroptosis factors were positively correlated with HOMA-IR and IGF1, and negatively with IGF1R and E2 levels.

CONCLUSION

MV improves PCOS by reducing pyroptosis and insulin resistance, enhancing insulin sensitivity, and promoting estrogen synthesis, thereby restoring granulosa cell function and follicular development.

Upregulated let-7 expression in the follicular fluid of patients with endometriomas leads to dysfunction of granulosa cells through targeting of IGF1R

STUDY QUESTION

What molecular mechanisms underlie the decline in ovarian reserve as the number and quality of oocytes decrease in patients with ovarian endometriomas (OEM)?

SUMMARY ANSWER

Elevated expression of the let-7 micro(mi)RNAs in the follicular microenvironment of OEM-affected ovaries targets the expression of type 1 insulin-like growth factor receptor (IGF1R) in granulosa cell (GC) and disrupts their proliferation, steroid hormone secretion levels, adenosine triphosphate (ATP) energy metabolism, and reactive oxygen species (ROS) oxidative stress levels.

WHAT IS KNOWN ALREADY

Patients with OEM exhibit diminished ovarian reserve, characterized by reduced oocyte quantity and quality. Fibrotic changes in the ovarian tissue surrounding the OEM create a disruptive microenvironment for follicular growth and development.

STUDY DESIGN, SIZE, DURATION

This is a cross-sectional study aimed to elucidate the molecular mechanisms underlying the impact of OEM on follicular development. Initially, miRNA expression profiles in follicular fluid (FF) samples were sequenced from patients with infertility related to OEM (N = 3) and male factor (MF) infertility (N = 3), with the latter serving as the control group. Differentially expressed miRNAs were validated in additional samples from each group (N = 55 in OEM group and N = 45 in MF group) to confirm candidate miRNAs. The study also investigated indicators associated with GCs dysfunction in vitro on rat GCs. Subsequently, rat models of OEM were established through endometrial allogeneic transplantation, and fertility experiments were conducted to assess the let-7/IGF1R axis response to OEM in vivo. Patient samples were collected between May 2018 and April 2019, and the mechanistic study was conducted over the subsequent three years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

FF and GC samples were obtained from infertile patients undergoing IVF treatment for OEM and MF related infertility. miRNA expression profiles in FF samples were analyzed using second-generation high-throughput sequencing technology, and candidate miRNAs were validated through quantitative PCR (qPCR). In the in vitro experiments conducted with rat GCs, cell proliferation was assessed using the CCK-8 assay, while steroid hormone concentrations were measured using chemiluminescence. ATP content was determined with an ATP assay kit, and levels of ROS were quantified using flow cytometry. A dual luciferase reporter gene assay was employed to identify the target gene of let-7 based on the construction of a IGF1R reporter gene plasmid using 293T cells. Western blotting was utilized to evaluate the expression of IGF1R in GCs, as well as its downstream proteins, and changes in signaling pathways following let-7 agomir/antagomir transfection and/or Igf1r silencing. In the in vivo OEM rat models, alterations in ovarian structure and cyst morphology were observed using hematoxylin and eosin staining. The expressions of let-7 and Igf1r in GCs were evaluated through qPCR, while variations in IGF1R expression were investigated with immunohistochemistry.

MAIN RESULTS AND THE ROLE OF CHANCE

The cohort of patients with ovarian OEM in this study exhibited significantly decreased antral follicle counts, oocyte retrieval numbers, and normal fertilization rates compared to the control group with MF. The expression of the let-7 miRNA family was markedly upregulated in the FF and GCs of OEM patients. Transfection of rat GCs with let-7 agonists diminished the functions of GCs, including disrupted cell proliferation, mitochondrial oxidative phosphorylation, and steroid hormone secretion, while transfection of rat GCs with let-7 antagonists caused the opposite effects. Luciferase reporter gene experiments confirmed that let-7 complementarily bound to the 3'-untranslated regions of IGF1R. Stimulation of let-7 expression in rat GCs led to a significant decrease in IGF1R expression, while inhibition of let-7 increased IGF1R expression. The expression of IGF1R in the GCs of OEM patients was also significantly reduced compared to MF patients. Silencing of Igf1r led to the dysfunction of GCs, similar to the effects of let-7 agonization, as demonstrated by the downregulation of key proteins involved in cell proliferation (CCND2 and CCND3) and oestradiol synthesis, as well as an increase in progesterone synthesis (StAR), while implicating the PI3K-Akt and MAPK signaling pathways. The antagonistic effect of let-7 on GCs was ineffective when Igf1r was silenced. Conversely, the agonistic effect of let-7 on GCs could be reversed by stimulation with the IGF1R ligand IGF-1. These findings suggested that let-7 regulated the proliferation, differentiation, and ATP synthesis of GCs through targeting IGF1R. The OEM rat model demonstrated alterations in ovarian morphology and structure, along with reduced fertility. Let-7 expression was significantly upregulated in GCs of OEM rats compared to normal rats, while Igf1r and IGF1R expression in pre-ovulatory follicular GCs were notably downregulated, supporting the notion that elevated let-7 expression in the follicular microenvironment of OEM inhibited IGF1R, leading to abnormal GC function and impacting fertility at the molecular level.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

The synthesis and secretion mechanisms of steroid hormones are intricate and complex. Some enzymes that regulate oestrogen synthesis also play a role in progesterone synthesis. Moreover, certain receptors can respond to multiple hormone signals. Therefore, in this study, the expression patterns of key enzymes such as CYP17A, CYP11A1, HSD3B2, StAR, and receptors including AR, LHCGR, FSHR, ESR2, might be influenced by various factors and might not demonstrate complete consistency.

WIDER IMPLICATIONS OF THE FINDINGS

Future research will concentrate on investigating the potential impact of ovarian stromal cells on the external microenvironment of follicle growth. Additionally, screening for small molecule drugs that target let-7 and IGF1R actions can be conducted to intervene and modify the ovarian microenvironment, ultimately enhancing ovarian function.

STUDY FUNDING/COMPETING INTEREST(S)

This study received funding from the National Natural Science Foundation of China (grant number 82301851 to L.B.S., grant numbers U23A20403 and U20A20349 to S.Y.Z., and grant number 82371637 to Y.D.D.) and the Natural Science Foundation of Zhejiang Province (grant LTGY23H040010 to F.Z.). The authors have no conflicts of interest to declare.

miR-134-3p Regulates Cell Proliferation and Apoptosis by Targeting INHBA via Inhibiting the TGF-β/PI3K/AKT Pathway in Sheep Granulosa Cells

Inhibin β-A (INHBA), a TGF-β superfamily member, is crucial for developing follicles. Although miRNAs are essential for post-transcriptional gene regulation, it is not yet known how they affect the expression of INHBA during follicle development. Using bioinformatics analyses, miR-134-3p was found, in this investigation, to be a crucial microRNA that targets INHBA in sheep GCs. Furthermore, when the follicular diameter expanded, there was a discernible decline in miR-134-3p expression. The miR-134-3p overexpression markedly reduced the proliferation of GCs, whereas its knockdown augmented it. Moreover, cell cycle progression was enhanced by miR-134-3p overexpression. Furthermore, miR-134-3p overexpression heightened GC apoptosis, while its knockdown reduced it. Importantly, miR-134-3p overexpression blocked the PI3K/AKT/mTOR axis, whereas its knockdown stimulated it. Overall, the outcomes of transfections with INHBA and miR-134-3p showed that, in sheep GCs, miR-134-3p targets INHBA to control cell proliferation and apoptosis. In summary, these results add to our understanding of the molecular mechanisms involving important miRNAs in ewe fecundity by indicating that miR-134-3p influences cell proliferation, cell apoptosis, and the TGF-β/PI3K/AKT/mTOR axis, which, in turn, influences the follicular development of sheep GCs.

Prenatal exposure to diethylstilbestrol has multigenerational effects on folliculogenesis

Diethylstilbestrol (DES) is an estrogenic endocrine disrupting chemical (EDC) that was prescribed to millions of pregnant women worldwide, leading to increased rates of infertility in the exposed offspring. We have previously demonstrated that this reduced fertility persists for multiple generations in the mouse. However, how altered ovarian function contributes to this infertility is unknown. Therefore, this study sought to determine if DES exposure promotes two common ovarian disorders, primary ovarian insufficiency (POI) and polycystic ovary syndrome, contributing to the reduced fertility in DES offspring. Moreover, we investigated if these impacts are transgenerational. Gestating mice were exposed to 100 µg/kg DES, and ovarian morphology was observed in F1-F3 female descendants. F1 females trended towards fewer primordial and more secondary follicles and similarly, F2 females had fewer primordial and significantly more secondary follicles compared to controls. No differences in follicle proportions were observed in the F3. Moreover, DES exposure did not increase follicular cysts. These results show that DES accelerates folliculogenesis, indicative of a POI phenotype and that this is likely contributing to the reduced fertility observed in DES descendants. Moreover, this study highlights the ability of estrogenic EDCs to disrupt folliculogenesis, which may exacerbate the onset of POI in women already at risk.

miRNAs in ovarian disorders: Small but strong cast

PURPOSE

This research aimed to analyze alterations in microRNA expression in the diseases POF (Premature Ovarian Failure), PCOS (Polycystic Ovarian Syndrome), and ovarian cancer in order to understand the molecular changes associated with these conditions. The findings could potentially be utilized for diagnostic, therapeutic, predictive, and preventive purposes. Furthermore, the impact and role of microRNAs in each ailment, along with their functional pathways, were elucidated and examined.

METHODS

In this study, the genes involved in the disease were studied, and then the miRNAs that targeted these genes were evaluated, and finally the signaling and functional pathways of each of the miRNAs were assessed. In this process, genetic databases and previous studies were carefully assessed.

RESULTS

miRNAs are short nucleotide sequences that belong to the category of non-coding RNAs. They play a crucial role in various physiological activities, including cell division, growth, differentiation, and cell death (necrosis and apoptosis), miRNAs are involved in various physiological processes Such alterations are common in various diseases, including cancer. miRNAs are involved in various physiological processes, such as folliculogenesis and steroidogenesis, as well as in pathological conditions such as POF, PCOS, and ovarian cancer. They have powerful regulatory effects and controlling the most activities of normal and pathological cells. While microRNAs (miRNAs) play a significant role in normal ovarian functions, there are reports of their expression changes in PCOS, ovarian cancer, and POF.

CONCLUSIONS

miRNAs have been found to exert significant influence on both physiological and pathological cellular processes. Understanding the dynamic patterns of miRNA alterations can provide valuable insights for researchers and therapists, enabling them to utilize these biomarkers effectively in diagnostic, therapeutic, and preventive applications.

Testosterone-Induced H3K27 Deacetylation Participates in Granulosa Cell Proliferation Suppression and Pathogenesis of Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is the leading cause of infertility in reproductive-age women. Hyperandrogenism, polycystic ovaries, and chronic anovulation are its typical clinical features. However, the correlation between hyperandrogenism and ovarian follicle growth aberrations remains poorly understood. To advance our understanding of the molecular alterations in ovarian granulosa cells (GCs) with excessive androgen, epigenetic changes and affected gene expression in human granulosa-lutein cells and immortalized human GCs were evaluated. A PCOS mouse model induced by dihydrotestosterone was also established. This study found that excessive testosterone significantly decreased the acetylation of lysine 27 on histone H3 (H3K27Ac). H3K27Ac chromatin immunoprecipitation-sequencing data showed down-regulated expression of cell cycle-related genes CCND1, CCND3, and PCNA, which was confirmed by real-time quantitative PCR and Western blot analysis. Testosterone application impeding cell proliferation was also shown by Ki-67 immunofluorescence and flow-cytometric analysis. Moreover, testosterone influenced casein kinase 2 alpha (CK2α) nuclear translocation, which increased the phosphorylation level of histone deacetylase 2 (HDAC2). Inhibition of CK2α nuclear translocation or silenced HDAC2 expression efficiently retarded H3K27 acetylation. PCOS mouse model experiments also demonstrated decreased H3K27Ac and enhanced HDAC2 phosphorylation in GCs. Cell proliferation-related genes were also down-regulated in PCOS mouse GCs. In conclusion, hyperandrogenism in human and mouse GCs caused H3K27Ac aberrations, which are associated with CK2α nuclear translocation and HDAC2 phosphorylation, participating in abnormal follicle development in patients with PCOS.

Granulosa Cells-Related MicroRNAs in Ovarian Diseases: Mechanism, Facts and Perspectives

MicroRNAs (miRNAs) are a class of short single-stranded, noncoding RNAs that affect the translation of mRNAs by imperfectly binding to homologous 3'UTRs. Research on miRNAs in ovarian diseases is constantly expanding because miRNAs are powerful regulators of gene expression and cellular processes and are promising biomarkers. miRNA mimics, miRNA inhibitors and molecules targeting miRNAs (antimiRs) have shown promise as novel therapeutic agents in preclinical development. Granulosa cells (GCs) are supporting cells for developing oocytes in the ovary. GCs regulate female reproductive health by producing sex hormones and LH receptors. Increasing research has reported the relevance of miRNAs in GC pathophysiology. With in-depth studies of disease mechanisms, there are an increasing number of studies on the biomolecular pathways of miRNAs in gynecology and endocrinology. In the present review, we summarize the different functions of GC-related microRNAs in various ovarian disorders, such as polycystic ovary syndrome, premature ovarian insufficiency, premature ovarian failure and ovarian granulosa cell tumors.

Crosstalk Between Oxidative Stress and Epigenetics: Unveiling New Biomarkers in Human Infertility

The correlation between epigenetic alterations and the pathophysiology of human infertility is progressively being elucidated with the discovery of an increasing number of target genes that exhibit altered expression patterns linked to reproductive abnormalities. Several genes and molecules are emerging as important for the future management of human infertility. In men, microRNAs (miRNAs) like miR-34c, miR-34b, and miR-122 regulate apoptosis, sperm production, and germ cell survival, while other factors, such as miR-449 and sirtuin 1 (SIRT1), influence testicular health, oxidative stress, and mitochondrial function. In women, miR-100-5p, miR-483-5p, and miR-486-5p are linked to ovarian reserve, PCOS, and conditions like endometriosis. Mechanisms such as DNA methylation, histone modification, chromatin restructuring, and the influence of these non-coding RNA (ncRNA) molecules have been identified as potential perturbators of normal spermatogenesis and oogenesis processes. In fact, alteration of these key regulators of epigenetic processes can lead to reproductive disorders such as defective spermatogenesis, failure of oocyte maturation and embryonic development alteration. One of the primary factors contributing to changes in the key epigenetic regulators appear to be oxidative stress, which arises from environmental exposure to toxic substances or unhealthy lifestyle choices. This evidence-based study, retracing the major epigenetic processes, aims to identify and discuss the main epigenetic biomarkers of male and female fertility associated with an oxidative imbalance, providing future perspectives in the diagnosis and management of infertile couples.

Proanthocyanidins protects 3-NPA-induced ovarian function decline by activating SESTRIN2-NRF2-mediated oxidative stress in mice

Abnormal apoptosis of ovarian cells caused by oxidative stress is an important cause of premature ovarian failure (POF). Previous studies revealed that proanthocyanidins (PCs) are powerful natural antioxidants that can safely prevent oxidative damage in humans. However, the protective effect and mechanism of PCs on ovarian function during the course of POF remain unknown. In this study, female mice were injected with 3-nitropropionic acid (3-NPA) to establish an ovarian oxidative stress model; at the same time, the mice were treated with PC via gavage. Thereafter, the expression of various apoptosis genes, hormones, and related molecules was assessed. Compared with those in the control group, the ovarian index, follicle count at all levels, expression of MVH, PCNA and BCL2, and estradiol (E2) and progesterone (P) levels were significantly lower in the POF group, but significant recovery was observed in terms of MVH and PCNA expression and E2 and P levels in the POF + PCs group. The apoptosis marker genes BAX and ROS were significantly increased in the POF group but were notably restored in the POF + PCs group. In addition, the expression of Sestrin2, an antiapoptotic protein, was significantly increased in the PCs treatment group, as were the upstream and downstream regulatory factors NRF2 and SOD2, and the indices of the Sestrin2 overexpression group were similar to those of the PCs treatment group. In summary, these findings suggest that PCs have potential as innovative therapeutic agents for preventing and treating POF by activating the protective SESTRIN2-NRF2 pathway against oxidative stress.

Inducers and Inhibitors of Pyroptotic Death of Granulosa Cells in Models of Premature Ovarian Insufficiency and Polycystic Ovary Syndrome

Granulosa cells (GCs), the largest cell population and primary source of steroid hormones in the ovary, are the important somatic ovarian components. They have critical roles in folliculogenesis by supporting oocyte, facilitating its growth, and providing a microenvironment suitable for follicular development and oocyte maturation, thus having essential functions in maintaining female fertility and in reproductive health in general. Pyroptotic death of GCs and associated inflammation have been implicated in the pathogenesis of several reproductive disorders in females including Premature Ovarian Insufficiency (POI) and Polycystic Ovary Syndrome (PCOS). Here, I reviewed factors, either intrinsic or extrinsic, that induce or inhibit pyroptosis in GCs in various models of these disorders, both in vitro and in vivo, and also covered associated molecular mechanisms. Most of these studied factors influence NLRP3 inflammasome- and GSDMD (Gasdermin D)-mediated pyroptosis in GCs, compared to other inflammasomes and gasdermins (GSDMs). I conclude that a more complete mechanistic understanding of these factors in terms of GC pyroptosis is required to be able to develop novel strategies targeting inflammatory cell death in the ovary.

LncRNA PKD1P6 modulates ovarian granulosa cell survival of hyperandrogenic polycystic ovary syndrome by targeting miR-135b-5p and inhibiting ERK1/2 signaling

Polycystic ovary syndrome (PCOS) is the most common and multifactorial endocrine disease among women of reproductive age. Aberrant folliculogenesis is a common pathological characteristic of PCOS, but the underlying molecular mechanism remains unclear. Emerging evidence indicated that aberrant expression of long noncoding RNAs (lncRNAs) may contribute to the pathogenesis of PCOS. In this study, we found that lncRNA PKD1P6 expression was remarkably down-regulated in ovarian granulosa cells (GCs) of hyperandrogenic PCOS (HA-PCOS) patients and negatively correlated with serum testosterone (T) levels. We further showed that overexpression of PKD1P6 markedly reduced cell viability, attenuated DNA synthesis capacity, arrested the cell cycle at G0/G1 phase and promoted apoptosis of KGN cells. Exosomes derived from PKD1P6 overexpression cells exerted similar effects to PKD1P6 overexpression on the function of KGN cells. Mechanistically, PKD1P6 could act as a competing endogenous RNA (ceRNA) by directly binding with miR-135b-5p. Overexpression of PKD1P6 significantly suppressed ERK1/2 activation, whereas up-regulation of miR-135b-5p exerted an opposing effect. Additionally, excessive androgen was showed to diminish PKD1P6 expression while promote miR-135b-5p expression of PCOS models in vitro and vivo. Collectively, our findings delineate the clinical significance of PKD1P6 in HA-PCOS and the new regulatory mechanisms involved in abnormal folliculogenesis, providing a promising therapeutic target for HA-PCOS.

Granulosa cell insight: unraveling the potential of menstrual blood-derived stem cells and their exosomes on mitochondrial mechanisms in polycystic ovary syndrome (PCOS)

BACKGROUND

Polycystic ovary syndrome (PCOS) presents a significant challenge in women's reproductive health, characterized by disrupted folliculogenesis and ovulatory dysfunction. Central to PCOS pathogenesis are granulosa cells, whose dysfunction contributes to aberrant steroid hormone production and oxidative stress. Mitochondrial dysfunction emerges as a key player, influencing cellular energetics, oxidative stress, and steroidogenesis. This study investigates the therapeutic potential of menstrual blood-derived stem cells (MenSCs) and their exosomes in mitigating mitochondrial dysfunction and oxidative stress in PCOS granulosa cells.

METHODS

Using a rat model of PCOS induced by letrozole, granulosa cells were harvested and cultured. MenSCs and their exosomes were employed to assess their effects on mitochondrial biogenesis, oxidative stress, and estrogen production in PCOS granulosa cells.

RESULTS

Results showed diminished mitochondrial biogenesis and increased oxidative stress in PCOS granulosa cells, alongside reduced estrogen production. Treatment with MenSCs and their exosomes demonstrated significant improvements in mitochondrial biogenesis, oxidative stress levels, and estrogen production in PCOS granulosa cells. Further analysis showed MenSCs' superior efficacy over exosomes, attributed to their sustained secretion of bioactive factors. Mechanistically, MenSCs and exosomes activated pathways related to mitochondrial biogenesis and antioxidative defense, highlighting their therapeutic potential for PCOS.

CONCLUSIONS

This study offers insights into granulosa cells mitochondria's role in PCOS pathogenesis and proposes MenSCs and exosomes as a potential strategy for mitigating mitochondrial dysfunction and oxidative stress in PCOS. Further research is needed to understand underlying mechanisms and validate clinical efficacy, presenting promising avenues for addressing PCOS complexity.

Does the miR-105-1-Kisspeptin Axis Promote Ovarian Cell Functions?

The objective of this study was to elucidate the intricate interplay among miR-105-1, kisspeptin, and their synergistic influence on basic ovarian granulosa cell functions. The effects of miR-105-1 mimics or miR-105-1 inhibitor, kisspeptin (0, 1, and 10 ng/ml), and its combinations with miR-105-1 mimics on porcine granulosa cells were assessed. The expression levels of miR-105-1, viability, proliferation (accumulation of PCNA, cyclin B1, XTT-, and BrdU-positive cells), apoptosis (accumulation of bcl-2, bax, caspase 3, p53, TUNEL-positive cells), proportion of kisspeptin-positive cells, and the release of steroid hormones and IGF-I were analyzed. Transfection of cells with miR-105-1 mimics promoted cell viability and proliferation, the occurrence of kisspeptin, and the release of progesterone and IGF-I; in contrast, miR-105-1 mimics inhibited apoptosis and estradiol output. MiR-105-1 inhibitor had the opposite effect. Kisspeptin amplified the expression of miR-105-1, cell viability, proliferation, steroid hormones, and IGF-I release and reduced apoptosis. Furthermore, the collaborative action of miR-105-1 mimics and kisspeptin revealed a synergistic relationship wherein miR-105-1 mimics predominantly supported the actions of kisspeptin, while kisspeptin exhibited a dual role in modulating the effects of miR-105-1 mimics. These findings not only affirm the pivotal role of kisspeptin in regulating basic ovarian cell functions but also represent the inaugural evidence underscoring the significance of miR-105-1 in this regulatory framework. Additionally, our results show the ability of kisspeptin to promote miR-105-1 expression and the ability of miR-105-1 to promote the occurrence and effects of kisspeptin and, therefore, indicate the existence of the self-stimulating kisspeptin-miR-105-1 axis.

Toxicity mechanism of acrolein on energy metabolism disorder and apoptosis in human ovarian granulosa cells

Acrolein (ACR), an unsaturated, highly reactive aldehyde, is a widespread environmental toxin. ACR exerts permanent and irreversible side effects on ovarian functions. Granulosa cells play a crucial role in supporting ovarian function. Thus, in this study, we investigated the toxicity effects of granulosa cells induced by ACR. Following treatment with varying ACR concentrations (0, 12.5, 25, 50, and 100 μM), we observed that ACR exposure induced reactive oxygen species accumulation, mitochondrial energy metabolism disorder, and apoptosis in KGN cells (a human ovarian granulosa cell line) in a dose-dependent manner. In addition, mitochondrial biogenesis in KGN cells displayed biphasic changes after ACR exposure, with activation at a low ACR dose (12.5 μM), but inhibition at higher ACR doses (≥50 μM). SIRT1/PGC-1α-mediated mitochondrial biogenesis is crucial for maintaining intracellular mitochondrial homeostasis and cellular function. The inhibition/activation of the SIRT1/PGC-1α pathway in KGN cells validated its role in ACR-induced damage. The results indicated that the inhibition of the SIRT1/PGC-1α pathway aggravated ACR-induced cell damage, whereas its activation partially counteracted ACR-induced cell damage. This study attempted to uncover a novel mechanism of ACR-induced ovarian toxicity so as to provide an effective treatment option for safeguarding female reproductive health from the adverse effects of ACR.

Probiotics an emerging therapeutic approach towards gut-brain-axis oriented chronic health issues induced by microplastics: A comprehensive review

Applications for plastic polymers can be found all around the world, often discarded without any prior care, exacerbating the environmental issue. When large waste materials are released into the environment, they undergo physical, biological, and photo-degradation processes that break them down into smaller polymer fragments known as microplastics (MPs). The time it takes for residual plastic to degrade depends on the type of polymer and environmental factors, with some taking as long as 600 years or more. Due to their small size, microplastics can contaminate food and enter the human body through food chains and webs, causing gastrointestinal (GI) tract pain that can range from local to systemic. Microplastics can also acquire hydrophobic organic pollutants and heavy metals on their surface, due to their large surface area and surface hydrophobicity. The levels of contamination on the microplastic surface are significantly higher than in the natural environment. The gut-brain axis (GB axis), through which organisms interact with their environment, regulate nutritional digestion and absorption, intestinal motility and secretion, complex polysaccharide breakdown, and maintain intestinal integrity, can be altered by microplastics acting alone or in combination with pollutants. Probiotics have shown significant therapeutic potential in managing various illnesses mediated by the gut-brain axis. They connect hormonal and biochemical pathways to promote gut and brain health, making them a promising therapy option for a variety of GB axis-mediated illnesses. Additionally, taking probiotics with or without food can reduce the production of pro-inflammatory cytokines, reactive oxygen species (ROS), neuro-inflammation, neurodegeneration, protein folding, and both motor and non-motor symptoms in individuals with Parkinson's disease. This study provides new insight into microplastic-induced gut dysbiosis, its associated health risks, and the benefits of using both traditional and next-generation probiotics to maintain gut homeostasis.

The reduction of the m6A methyltransferase METTL3 in granulosa cells is related to the follicular cysts in pigs

Follicular cysts are a common reproductive disorder in domestic animals that cause considerable economic losses to the farming industry. Effective prevention and treatment methods are lacking because neither the pathogenesis nor formation mechanisms of follicular cysts are well-understood. In this study, we first investigated the granulosa cells (GCs) of cystic follicles isolated from pigs. We observed a significant reduction in the expression of methyltransferase-like 3 (METTL3). Subsequent experiments revealed that METTL3 downregulation in GCs caused a decrease in m6A modification of pri-miR-21. This reduction further inhibited DGCR8 recognition and binding to pri-miR-21, dampening the synthesis of mature miR-21-5p. Additionally, the decrease in miR-21-5p promotes IL-1β expression in GCs. Elevated IL-1β activates the NFκB pathway, in turn upregulating apoptotic genes TNFa and BAX/BCL2. The subsequent apoptosis of GCs and inhibition of autophagy causes downregulation of CYP19A1 expression. These processes lower oestrogen secretion and contribute to follicular cyst formation. In conclusion, our findings provide a foundation for understanding and further exploring the mechanisms of follicular-cyst development in farm animals. This work has important implications for treating ovarian disorders in livestock and could potentially be extended to humans.

Ti3C2 nanosheet-induced autophagy derails ovarian functions

BACKGROUND

Two-dimensional ultrathin Ti3C2 (MXene) nanosheets have gained significant attention in various biomedical applications. Although previous studies have described the accumulation and associated damage of Ti3C2 nanosheets in the testes and placenta. However, it is currently unclear whether Ti3C2 nanosheets can be translocated to the ovaries and cause ovarian damage, thereby impairing ovarian functions.

RESULTS

We established a mouse model with different doses (1.25, 2.5, and 5 mg/kg bw/d) of Ti3C2 nanosheets injected intravenously for three days. We demonstrated that Ti3C2 nanosheets can enter the ovaries and were internalized by granulosa cells, leading to a decrease in the number of primary, secondary and antral follicles. Furthermore, the decrease in follicles is closely associated with higher levels of FSH and LH, as well as increased level of E2 and P4, and decreased level of T in mouse ovary. In further studies, we found that exposure toTi3C2 nanosheets increased the levels of Beclin1, ATG5, and the ratio of LC3II/Ι, leading to autophagy activation. Additionally, the level of P62 increased, resulting in autophagic flux blockade. Ti3C2 nanosheets can activate autophagy through the PI3K/AKT/mTOR signaling pathway, with oxidative stress playing an important role in this process. Therefore, we chose the ovarian granulosa cell line (KGN cells) for in vitro validation of the impact of autophagy on the hormone secretion capability. The inhibition of autophagy initiation by 3-Methyladenine (3-MA) promoted smooth autophagic flow, thereby partially reduced the secretion of estradiol and progesterone by KGN cells; Whereas blocking autophagic flux by Rapamycin (RAPA) further exacerbated the secretion of estradiol and progesterone in cells.

CONCLUSION

Ti3C2 nanosheet-induced increased secretion of hormones in the ovary is mediated through the activation of autophagy and impairment of autophagic flux, which disrupts normal follicular development. These results imply that autophagy dysfunction may be one of the underlying mechanisms of Ti3C2-induced damage to ovarian granulosa cells. Our findings further reveal the mechanism of female reproductive toxicity induced by Ti3C2 nanosheets.

Insight into vitamin D3 action within the ovary-Basic and clinical aspects

Vitamin D3 is a fat-soluble secosteroid predominantly synthesized in the skin or delivered with a diet. Nevertheless, recently it is considered more as a hormone than a vitamin due to its pleiotropic function within the organism ensured by widely distributed vitamin D receptors and metabolic enzymes. Besides the main role in calcium and phosphorus homeostasis, vitamin D3 was shown to regulate many cellular and metabolic processes in normal and cancerous tissues within the immune system, the cardiovascular system, the respiratory system and the endocrine system. The ovary is an important extraskeletal tissue of vitamin D3 action and local metabolism, indicating its role in the regulation of ovarian functions upon physiological and pathological conditions. This chapter reviews firstly the updated information about vitamin D3 metabolism and triggered intracellular pathways. Furthermore, the basic information about ovarian physiology and several aspects of vitamin D3 effects within the ovary are presented. Finally, the special attention is paid into possible mechanism of vitamin D3 action within ovarian pathologies such as premature ovarian failure, polycystic ovary syndrome, and ovarian cancer, considering its clinical application as alternative therapy.

miRNA expression in PCOS: unveiling a paradigm shift toward biomarker discovery

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that affects a substantial percentage of women, estimated at around 9-21%. This condition can lead to anovulatory infertility in women of childbearing age and is often accompanied by various metabolic disturbances, including hyperandrogenism, insulin resistance, obesity, type-2 diabetes, and elevated cholesterol levels. The development of PCOS is influenced by a combination of epigenetic alterations, genetic mutations, and changes in the expression of non-coding RNAs, particularly microRNAs (miRNAs). MicroRNAs, commonly referred to as non-coding RNAs, are approximately 22 nucleotides in length and primarily function in post-transcriptional gene regulation, facilitating mRNA degradation and repressing translation. Their dynamic expression in different cells and tissues contributes to the regulation of various biological and cellular pathways. As a result, they have become pivotal biomarkers for various diseases, including PCOS, demonstrating intricate associations with diverse health conditions. The aberrant expression of miRNAs has been detected in the serum of women with PCOS, with overexpression and dysregulation of these miRNAs playing a central role in the atypical expression of endocrine hormones linked to PCOS. This review takes a comprehensive approach to explore the upregulation and downregulation of various miRNAs present in ovarian follicular cells, granulosa cells, and theca cells of women diagnosed with PCOS. Furthermore, it discusses the potential for a theragnostic approach using miRNAs to better understand and manage PCOS.

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.

miR-6881-3p contributes to diminished ovarian reserve by regulating granulosa cell apoptosis by targeting SMAD4

BACKGROUND

In our previous investigation, we revealed a significant increase in the expression of microRNA-6881-3p (miR-6881-3p) in follicular fluid granulosa cells (GCs) from women with diminished ovarian reserve (DOR) compared to those with normal ovarian reserve (NOR). However, the role of miR-6881-3p in the development of DOR remains poorly understood.

OBJECTIVE

This study aimed to elucidate the involvement of miR-6881-3p in the regulation of granulosa cells (GCs) function and the pathogenesis of DOR.

MATERIALS AND METHODS

Initially, we assessed the expression levels of miR-6881-3p in GCs obtained from human follicular fluid in both NOR and DOR cases and explored the correlation between miR-6881-3p expression and clinical outcomes in assisted reproduction technology (ART). Bioinformatic predictions and dual-luciferase reporter assays were employed to identify the target gene of miR-6881-3p. Manipulation of miR-6881-3p expression was achieved through the transfection of KGN cells with miR-6881-3p mimics, inhibitor, and miRNA negative control (NC). Following transfection, we assessed granulosa cell apoptosis and cell cycle progression via flow cytometry and quantified target gene expression through quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot (WB) analysis. Finally, we examined the correlation between target gene expression levels in GCs from NOR and DOR patients and their association with ART outcomes.

RESULTS

Our findings revealed elevated miR-6881-3p levels in GCs from DOR patients, which negatively correlated with ovarian reserve function and ART outcomes. We identified a direct binding interaction between miR-6881-3p and the 3'-untranslated region of the SMAD4. Transfection with miR-6881-3p mimics induced apoptosis in KGN cell. Furthermore, miR-6881-3p expression negatively correlated with both mRNA and protein levels of the SMAD4. The mRNA and protein levels of SMAD4 were notably reduced in GCs from DOR patients, and SMAD4 mRNA expression positively correlated with ART outcomes. In addition, the mRNA levels of FSHR, CYP11A1 were notably reduced after transfection with miR-6881-3p mimics in KGN cell, while LHCGR notably increased. The mRNA and protein levels of FSHR, CYP11A1 were notably reduced in GCs from DOR patients, while LHCGR notably increased.

CONCLUSION

This study underscores the role of miR-6881-3p in directly targeting SMAD4 mRNA, subsequently diminishing granulosa cell viability and promoting apoptosis, and may affect steroid hormone regulation and gonadotropin signal reception in GCs. These findings contribute to our understanding of the pathogenesis of DOR.

A glance into the roles of microRNAs (exosomal and non-exosomal) in polycystic ovary syndrome

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder in women of reproductive age. The clinical symptoms include hyperandrogenism, chronic anovulation, and multiple ovarian cysts. PCOS is strongly associated with obesity and insulin resistance. MicroRNAs (miRNAs) are a group of short non-coding RNAs that play a role in the post-transcriptional regulation of gene expression and translational inhibition. They play a vital role in the regulation of multiple metabolic and hormonal processes as well as in oocyte maturation and folliculogenesis in the female reproductive system. miRNAs can be used as diagnostic biomarkers or therapeutic targets because of their stability. The encapsulation of miRNAs in extracellular vesicles or exosomes contributes to their stability. Exosomes are constantly secreted by many cells and size of about 30 to 150 nm. Enveloping miRNAs exosomes can release them for cellular communication. The induced transfer of miRNAs by exosomes is a novel process of genetic exchange between cells. Many studies have shown that along with non-exosomal miRNAs, different types of exosomal miRNAs derived from the serum and follicular fluid can play an essential role in PCOS pathogenesis. These miRNAs are involved in follicular development and various functions in granulosa cells, apoptosis, cell proliferation, and follicular atresia. The present study aimed to comprehensively review the evidence on miRNAs and their affected pathways under both non-exosomal and exosomal circumstances, primarily focusing on the pathogenesis of PCOS.

Computational investigation of four isoquinoline alkaloids against polycystic ovarian syndrome

Hyperandrogenism, insulin resistance, and estrogen dominance are the prime defining traits of women with polycystic ovarian syndrome which disrupts hormonal, adrenal, or ovarian functions resulting in impaired folliculogenesis and excess androgen production. The purpose of this study is to identify an appropriate bioactive antagonistic ligand from isoquinoline alkaloids [palmatine (PAL), jatrorrhizine (JAT), magnoflorine (MAG) and berberine (BBR)] from stems of Tinospora cordifolia. Phytocomponents inhibit/prevent androgenic, estrogenic, and steroidogenic receptors, insulin binding, and resultant hyperandrogenism. Intending to develop new inhibitors for human androgen receptor (1E3G), insulin receptor (3EKK), estrogen receptor beta (1U3S), and human steroidogenic cytochromeP450 17A1 (6WR0), here we report the docking studies by employing a flexible ligand docking approach using AutodockVina 4.2.6. ADMET screened swissADME and toxicological predictions to identify novel and potent inhibitors against PCOS. Binding affinity was obtained using Schrodinger. Two ligands, mainly BER (-8.23) and PAL (-6.71) showed the best docking score against androgen receptors. A molecular docking study reveals that compounds BBR and PAL were found to be tight binder at the active site of IE3G. Molecular dynamics results suggest that BBR and PAL showed good binding stability of active site residues. The present study corroborates the molecular dynamics of the compound BBR and PAL, potent Inhibitors of IE3G, having therapeutic potential for PCOS. We project that this study's findings will be helpful in drug development efforts targeting PCOS. Hence isoquinoline alkaloids (BER& PAL) have potential roles against androgen receptors, and in specific PCOS, scientific evaluation has been put forth based on virtual screening.Communicated by Ramaswamy H. Sarma.

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.

DDIT4 is essential for DINP-induced autophagy of ovarian granulosa cells

As one of the most important phthalates, di-isononyl phthalate (DINP) has been widely used as a common plasticizer in the food and personal care products sectors. In our previous study, we found that DINP can induce autophagy of ovarian granulosa cells; while the underlying mechanism is unclear. In the study, we showed that DINP exposure could induce autophagy of ovarian granulosa cells and KGN cells, accompanied with the increase in the mRNA and protein level of DDIT4. Furthermore, overexpression of DDIT4 were shown to induce autophagy of KGN cells; while knockdown of DDIT4 inhibited DINP-induced autophagy, implying that DDIT4 played an important role in DINP-induced autophagy of ovarian granulosa cells. There were three putative binding sites of transcription factor ATF4 in the promoter region of DDIT4 gene, suggesting that DDIT4 might be regulated by ATF4. Herein, we found that overexpression of ATF4 could upregulate the expression of DDIT4 in KGN cells, while knockdown of ATF4 inhibited its expression. Subsequently, ATF4 was identified to bind to the promoter region of DDIT4 gene and promote its transcription. The expression of ATF4 was also increased in the DINP-exposed granulosa cells, and ATF4 overexpression promoted autophagy of KGN cells; whereas knockdown of ATF4 alleviated DINP-induced upregulation of DDIT4 and autophagy of the cells. Taken together, DINP triggered autophagy of ovarian granulosa cells through activating ATF4/DDIT4 signals.

Identification of ID1 and miR-150 interaction and effects on proliferation and apoptosis in ovine granulosa cells

Granulosa cells (GCs) proliferation and apoptosis play a significantly role in follicular development and atresia. ID1 and miR-150 are involved in cell apoptosis and follicular atresia, but the interaction and function of ID1 and miR-150 in GCs are unclear. This study focuses on ID1 and miR-150 in terms of the interaction and effects on proliferation and apoptosis in ovine granulosa cells. Our findings revealed that ID1 decreased the promoter activity and expression level of oar-miR-150. However, the expression of ID1 was downregulated by miR-150, and ID1 was identified as a target gene of oar-miR-150. miR-150 mimic inhibited proliferation and upregulated apoptosis rate in ovine GCs, while the results of miR-150 inhibitor were opposite. Overexpression of ID1 significantly inhibited ovine GCs proliferation and cell cycle-related genes (CDK1, CDK2, CDK4, CCND2, CDC20, and PCNA) expression, whereas knockdown of ID1 promoted cell proliferation and those genes expression. Overexpression of ID1 significantly downregulated mitochondrial membrane potential and Bcl-2 expression in ovine GCs, and upregulated the expression of pro-apoptosis genes Bax, Caspase-3, and Caspase-9, whereas the results of ID1 knockdown were reversed. Collectively, these findings indicate the interaction and the vital role of ID1 and miR-150 on proliferation and apoptosis in ovine granulosa cells, which may suggest a novel target for ovine follicular development and atresia.

hsa_circRNA_BECN1 acts as a ceRNA to promote polycystic ovary syndrome progression by sponging the miR-619-5p/Rab5b axis

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disease that affects women of reproductive age. It is also a significant cause of infertility. Circular RNAs have been found to have a crucial role in the development and progression of reproductive system diseases. In this study, we focused on circ_BECN1 and aimed to investigate its role and mechanism in PCOS, providing a foundation for early diagnosis and treatment of this condition. Our findings revealed an upregulation of circ_BECN1 expression in the ovarian granulosa cells (GCs) of PCOS patients. Additionally, the silencing of circ_BECN1 resulted in inhibited proliferation and enhanced apoptosis of the human ovarian granulosa-like tumor cell line (KGN), therefore implicating circ_BECN1 in the cell cycle process. Through a dual-luciferase reporting assay, we determined that circ_BECN1 acts as a sponge for miR-619-5p and that Rab5b is the target gene of miR-619-5p. Moreover, the expression of Rab5b was found to be upregulated in the ovarian tissue of PCOS patients. Knocking down circ_BECN1 resulted in decreased Rab5b expression, which was then restored by using a miR-619-5p inhibitor. Additionally, rescue experiments demonstrated that overexpressing Rab5b reversed the effects of circ_BECN1 knockdown on cell proliferation and apoptosis in KGN cells. In summary, our findings indicate that circ_BECN1 is upregulated in PCOS GCs and promotes cell growth and cell cycle progression, and reduces cell apoptosis by modulating the miR-619-5p/Rab5b axis. Therefore, circ_BECN1 may serve as a potential therapeutic target for PCOS treatment.

Identification of transcriptome characteristics of granulosa cells and the possible role of UBE2C in the pathogenesis of premature ovarian insufficiency

BACKGROUND

Premature ovarian insufficiency (POI) is an important cause of infertility characterized by the functional decline of the ovary. Granulosa cells (GCs) around oocytes are critical for folliculogenesis, and GC dysfunction is one of the important etiologies of POI. The aim of this study was to explore the potential biomarkers of POI by identifying hub genes and analyze the correlation of biomarkers with immune infiltration in POI using RNA profiling and bioinformatics analysis.

METHODS

RNA sequencing was performed on GCs from biochemical POI (bPOI) patients and controls. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were used to explore the candidate genes. qRT‒PCR was performed to verify the expression of hub genes. Western blot, Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine (EdU) assays, TUNEL (TdT-mediated dUTP Nick-End Labeling) and flow cytometry analysis were used to validate the possible role of ubiquitin-conjugating enzyme 2C (UBE2C) in POI. CIBERSORT was adopted to explore immune cell infiltration and the correlation between UBE2C and immune cells in bPOI.

RESULTS

Through analysis of differentially expressed genes (DEGs) and WGCNA, we obtained 143 candidate genes. After construction of the protein‒protein interaction (PPI) network and analysis with Cytoscape, 10 hub genes, including UBE2C, PBK, BUB1, CDC20, NUSAP1, CENPA, CCNB2, TOP2A, AURKB, and FOXM1, were identified and verified by qRT‒PCR. Subsequently, UBE2C was chosen as a possible biomarker of POI because knockdown of UBE2C could inhibit the proliferation and promote the apoptosis of GCs. Immune infiltration analysis indicated that monocytes and M1 macrophages may be associated with the pathogenesis of POI. In addition, UBE2C was negatively correlated with monocytes and M1 macrophages in POI.

CONCLUSIONS

This study identified a hub gene in GCs that might be important in the pathogenesis of POI and revealed the key role of UBE2C in driving POI. Immune infiltration may be highly related with the onset and etiology of POI.

Maternal MicroRNA Profile Changes When LH Is Added to the Ovarian Stimulation Protocol: A Pilot Study

While the use of follicle-stimulating hormone (FSH) in ovarian stimulation for in vitro fertilization (IVF) is an established practice, the use of luteinizing hormone (LH) remains debatable. MicroRNAs (miRNAs) are short, endogenous, non-coding transcripts that control a variety of cellular functions, such as gonadotrophin production and follicular development. The goal of this pilot study was to investigate whether the employment of recombinant LH (rLH) in ovarian stimulation protocols results in changes in the miRNA profiles in human oocytes. Patients were divided into two groups: seven received recombinant FSH (rFSH, 225 IU), and six received rFSH (150 IU) plus rLH (75 IU). MiRNA predesigned panels and real-time PCR technology were used to analyze the oocytes retrieved from the follicular ovarian retrieval. Among the miRNAs evaluated, a series of them evidenced upregulation or downregulation in their expression in the FSH plus LH group compared to the FSH group. Considering the results obtained from the functional and network analysis, the different maternal miRNA profiles in the two groups revealed a differential modulation of pathways involved in numerous biological functions. Overall, based on the pathways associated with most of these maternal miRNAs, the presence of LH may result in a different modulation of pathways regulating survival under the control of a Tp53-related mechanism. Interestingly, among the miRNAs differentially expressed in oocytes of the two groups, we have found miRNAs already investigated at ovarian, follicular, oocyte, and embryonic levels: hsa-miR-484, hsa-miR-222, hsa-miR-520d-5p, hsa-miRNA-17, hsa-miR-548, and hsa-miR-140. Thus, investigation into the role of these miRNAs in oocyte molecular pathways may help determine how LH affects oocyte competence and eventually leads to the clinical improvement of IVF.

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.

MicroRNA-144-3p protects against chemotherapy-induced apoptosis of ovarian granulosa cells and activation of primordial follicles by targeting MAP3K9

Premature ovarian failure (POF) is defined by amenorrhea, ovarian atrophy, hypoestrogenism, elevated gonadotropin level, and infertility under the age of 40. POF is frequently induced by chemotherapeutic agents. However, the underlying mechanisms regarding chemotherapy-mediated damage to ovarian function are unclear. In this study, enhanced apoptosis of granulosa cells (GCs) and aberrant activation of primordial follicles were observed in a POF mouse model induced by cisplatin. We subsequently observed significant downregulation of miR-144-3p and upregulation of mitogen-activated protein kinase kinase kinase 9 (MAP3K9) in primary ovarian GCs from POF mice, as revealed by microarrays. Furthermore, MAP3K9 expression was higher in human ovarian granulosa cells (COV434) treated with cisplatin and was identified as a novel target of miR-144-3p. Functional analysis revealed that miR-144-3p attenuated cisplatin induced apoptosis of GCs via silencing MAP3K9 expression, which suppressed the activity of the downstream p38 mitogen activated protein kinase (MAPK) pathway. Meanwhile, miR-144-3p prevented premature primordial follicle depletion in cisplatin-induced POF mice through targeting Map3k9, which led to a decline in the phosphorylation and activation of the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase b (AKT) pathway. Taken together, this study revealed the protective effects of miR-144-3p on ovarian function and shed light on the epigenetic regulatory mechanism in the development of POF, which might provide new biomarkers for the ovarian reserve.

Therapeutic effects of human umbilical cord mesenchymal stem cell-derived extracellular vesicles on ovarian functions through the PI3K/Akt cascade in mice with premature ovarian failure

Premature ovarian failure (POF) mainly refers to ovarian dysfunction in females younger than forty. Mesenchymal stem cells (MSCs) are considered an increasingly promising therapy for POF. This study intended to uncover the therapeutic effects of human umbilical cord MSC-derived extracellular vesicles (hucMSCEVs) on POF. hucMSCs were identified by observing morphology and examining differentiation capabilities. EVs were extracted from hucMSCs and later identified utilizing nanoparticle tracking analysis, transmission electron microscopy, and Western blotting. POF mouse models were established by injecting D-galactose (Dgal). The estrous cycles were assessed through vaginal cytology, and serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), anti-mullerian hormone (AMH), estradiol (E2), and progesterone (P) were measured by ELISA. The human ovarian granulosa cell line KGN was used for in vitro experiments. The uptake of hucMSC-EVs by KGN cells was detected. After D-gal treatment, cell proliferation and apoptosis were assessed via CCK-8 assay and flow cytometry. The PI3K/Akt pathway-related proteins were determined by Western blotting. Our results revealed that POF mice had prolonged estrous cycles, increased FSH and LH levels, and decreased AMH, E2, and P levels. Treatment with hucMSC-EVs partially counteracted the above changes. D-gal treatment reduced proliferation and raised apoptosis in KGN cells, while hucMSC-EV treatment annulled the changes. D-gal-treated cells exhibited downregulated p-PI3K/PI3K and p-Akt/Akt levels, while hucMSC-EVs activated the PI3K/Akt pathway. LY294002 suppressed the roles of hucMSC-EVs in promoting KGN cell proliferation and lowering apoptosis. Collectively, hucMSC-EVs facilitate proliferation and suppress apoptosis of ovarian granulosa cells by activating the PI3K/Akt pathway, thereby alleviating POF.

Evaluation of the p53 pathway in polycystic ovarian syndrome pathogenesis and apoptosis enhancement in human granulosa cells through transcriptome data analysis

The polycystic ovarian syndrome (PCOS) is closely associated with enhanced apoptosis of granulosa cells, which have a vital role in maturation of oocytes. p53 plays a critical role in the regulation of apoptosis and cell cycle arrest, metabolism and insulin resistance. The aim of this study was to investigate the impact of p53 pathway in enhancing apoptosis and abnormal function of granulosa cells. In this study, microarray analysis and RNA sequencing were downloaded from the GEO and used as datasets. Principal Component Analysis (PCA) and online SSizer tool were applied to evaluate the experiment quality control and sample sufficiency, respectively. Bioinformatics' analyses were performed on the selected datasets, and validated by qRT-PCR and western blot analyses. Three datasets out of five ones were chosen for re-analyzing based on the PCA outcomes. 21 deregulated genes were identified via filters including p < 0.05 and |log2FC|≥ 1. Functional enrichment analysis confirmed the relevance of cell cycle regulation and apoptosis as common biological hallmarks in PCOS. Results have shown differentially expressed p53 target genes involved in apoptosis (BAX, FAS, PMAIP1, and CASP8), cell cycle (Cyclins, Cyclin dependent kinases), glucose metabolism and insulin resistance (THBS1), and p53 regulation (MDM2). Subsequently, the relative mRNA expression of FAS, PMAIP1 and MDM2 genes, and protein levels of p53 and MDM2 were confirmed using granulosa cells collected from 20 PCOS women and 18 control individuals by qRT-PCR and western blot, respectively. Results of this study represent the possible role of p53 pathway in pathogenesis of PCOS particularly, through the enhancement of apoptosis in granulosa cells.

MicroRNA miR-152 can support ovarian granulosa cell functions and modify apigenin actions

The study aimed to evaluate the involvement of apigenin, microRNA (miR)-152, and their interrelationships in the control of basic ovarian granulosa cell functions. The effects of apigenin (0, 10, and 100 µg/mL), miR-152 analogues or miR-152 inhibitor, and their combinations with apigenin on porcine granulosa cells were examined. Expression levels of miR-152, viability, proliferation, apoptosis, steroid hormones, IGF-I, oxytocin, and prostaglandin E2 release were analyzed. Apigenin increased the expression of miR-152, cell proliferation, and estradiol release and reduced apoptosis, progesterone, and IGF-I output. MicroRNA-152 analogues promoted cell viability and proliferation, as well as the release of progesterone, IGF-I, oxytocin, and prostaglandin E2; however, it inhibited apoptosis and estradiol output. miR-152 inhibitor had the opposite effect. Moreover, miR-152 analogues suppressed the effect of apigenin on cell apoptosis and estradiol release. These observations 1) confirm the involvement of apigenin in the control of basic ovarian cell functions; 2) are the first demonstration of importance of miR-152 in the control of these functions; 3) show the ability of apigenin to promote miR-152 expression and the ability of miR-152 to modify apigenin effects on ovarian cells.

Oxidative stress and mitochondrial dysfunction of granulosa cells in polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS) is one of the leading causes of anovulatory infertility in women, affecting 5%-15% of women of reproductive age worldwide. The clinical manifestations of patients include ovulation disorders, amenorrhea, hirsutism, and obesity. Life-threatening diseases, such as endometrial cancer, type 2 diabetes, hyperlipidaemia, hypertension, and cardiovascular disease, can be distant complications of PCOS. PCOS has diverse etiologies and oxidative stress (OS) plays an important role. Mitochondria, as the core organelles of energy production, are the main source of reactive oxygen species (ROS). The process of follicular growth and development is extremely complex, and the granulosa cells (GCs) are inextricably linked to follicular development. The abnormal function of GCs may directly affect follicular development and alter many symptoms of PCOS. Significantly higher levels of OS markers and abnormal mitochondrial function in GCs have been found in patients with PCOS compared to healthy subjects, suggesting that increased OS is associated with PCOS progression. Therefore, the aim of this review was to summarize and discuss the findings suggesting that OS and mitochondrial dysfunction in GCs impair ovarian function and induce PCOS.

EIF4A3-Induced Exosomal circLRRC8A Alleviates Granulosa Cells Senescence Via the miR-125a-3p/NFE2L1 axis

Premature ovarian failure (POF) is an important cause of female infertility and seriously impacts the physical and psychological health of patients. Mesenchymal stromal cells-derived exosomes (MSCs-Exos) have an essential role in the treatment of reproductive disorders, particularly POF. However, the biological function and therapeutic mechanism of MSCs exosomal circRNAs in POF remain to be determined. Here, with bioinformatics analysis and functional assays, circLRRC8A was found to be downregulated in senescent granulosa cells (GCs) and acted as a crucial factor in MSCs-Exos for oxidative damage protection and anti-senescence of GCs in vitro and in vivo. Mechanistic investigations revealed that circLRRC8A served as an endogenous miR-125a-3p sponge to downregulate NFE2L1 expression. Moreover, eukaryotic initiation factor 4A3 (EIF4A3), acting as a pre-mRNA splicing factor, promoted circLRRC8A cyclization and expression by directly binding to the LRRC8A mRNA transcript. Notably, EIF4A3 silencing reduced circLRRC8A expression and attenuated the therapeutic effect of MSCs-Exos on oxidatively damaged GCs. This study demonstrates a new therapeutic pathway for cellular senescence protection against oxidative damage by delivering circLRRC8A-enriched exosomes through the circLRRC8A/miR-125a-3p/NFE2L1 axis and paves the way for the establishment of a cell-free therapeutic approach for POF. CircLRRC8A may be a promising circulating biomarker for diagnosis and prognosis and an exceptional candidate for further therapeutic exploration.

miR-486 Responds to Apoptosis and Autophagy by Repressing SRSF3 Expression in Ovarian Granulosa Cells of Dairy Goats

The accumulation of ovarian granulosa cell (GC) apoptosis underlies follicular atresia. By comparing the previous sequencing results, miR-486 was found to be differentially expressed at higher levels in the monotocous goat than in the polytocous goat. Unfortunately, the miRNA-mediated mechanisms by which the GC fate is regulated are unknown in Guanzhong dairy goats. Therefore, we investigated miR-486 expression in small and large follicles, as well as its impact on normal GC survival, apoptosis and autophagy in vitro. Here, we identified and characterized miR-486 interaction with Ser/Arg-rich splicing factor 3 (SRSF3) using luciferase reporter analysis, detecting its role in GC survival, apoptosis and autophagy regulation through qRT-PCR, Western blot, CCK-8, EdU, flow cytometry, mitochondrial membrane potential and monodansylcadaverine, etc. Our findings revealed prominent effects of miR-486 in the regulation of GC survival, apoptosis and autophagy by targeting SRSF3, which might explain the high differential expression of miR-486 in the ovaries of monotocous dairy goats. In summary, this study aimed to reveal the underlying molecular mechanism of miR-486 regulation on GC function and its effect on ovarian follicle atresia in dairy goats, as well as the functional interpretation of the downstream target gene SRSF3.

Androgen-induced exosomal miR-379-5p release determines granulosa cell fate: cellular mechanism involved in polycystic ovaries

Polycystic ovarian syndrome (PCOS) is a complex multi-factorial syndrome associated with androgen excess and anovulatory infertility. In the current study, we investigated the role of dihydrotestosterone-induced exosomal miR-379-5p release in determining the destiny of the developing follicles. Our hypothesis was that androgen regulates granulosa cell miR-379-5p content by facilitating its exosomal release in a follicular-stage dependent manner, a process which determines granulosa cell fate. Compared to human non-PCOS subjects, individuals with PCOS exhibit higher follicular fluid free testosterone levels, lower exosomal miR-379-5p content and granulosa cell proliferation. Androgenized rats exhibited lower granulosa cell miR-379-5p but higher phosphoinositide-dependent kinase-1 (PDK1; a miR-379-5p target) content and proliferation. Androgen reduced granulosa cell miR-379-5p content by increasing its exosomal release in preantral follicles, but not in antral follicles in vitro. Studies with an exosomal release inhibitor confirmed that androgen-induced exosomal miR-379-5p release decreased granulosa cell miR-379-5p content and proliferation. Ovarian overexpression of miR-379-5p suppressed granulosa cell proliferation, and basal and androgen-induced preantral follicle growth in vivo. These findings suggest that increased exosomal miR-379-5p release in granulosa cells is a proliferative response to androgenic stimulation specific for the preantral stage of follicle development and that dysregulation of this response at the antral stage is associated with follicular growth arrest, as observed in human PCOS.

Involvement of microRNA miR-125b in the control of porcine ovarian cell functions

The existing knowledge of the involvement of miR-125b in the control of ovarian functions is insufficient. To evaluate the role of miR-125b in the control of basic porcine ovarian granulosa cell functions, we examined the upregulation (using miR-125b mimics) and downregulation (using miR-125b inhibitor) of this miR-125b. Expression levels of miR-125b, viability, proliferation (expression and accumulation of PCNA and cyclin B1), the proportion of proliferative active cells, apoptosis (expression and accumulation of bax and caspase 3), the proportion of cells containing DNA fragmentation, steroid hormones, IGF-I, oxytocin, and prostaglandin E2 release were analysed by RT-qPCR, Trypan blue exclusion test, quantitative immunocytochemistry, XTT and TUNEL assays, and ELISA. Transfection of cells with miR-125b mimics decreased cell viability, proliferation, and the release of progesterone, testosterone, estradiol, and oxytocin, but stimulated apoptosis and prostaglandin E2 output. Transfection of cells with miR-125b inhibitor had the opposite effect. Moreover, it prevented the effects of miR-125b mimics. Our observations suggest that miR-125b is a potent physiological inhibitor of granulosa ovarian cell functions - cell cycle, apoptosis, and secretory activity.

MicroRNA miR-125b can suppress ovarian granulosa cell functions: Interrelationships with FSH

This study aimed to evaluate the involvement of miR-125b and its interrelationship with follicle-stimulating hormone (FSH) in the control of basic ovarian granulosa cell functions. The effect of miR-125b mimics on basic functions of porcine ovarian granulosa cells cultured with and without FSH, and the effect of FSH on the expression of endogenous miR-125b was examined. Expression levels of miR-125b, viability, proliferation (accumulation of PCNA and cyclin B1), apoptosis (accumulation of bax and caspase 3), the accumulation of FSH receptors (FSHR), steroid hormones, insulin-like growth factor I (IGF-I), oxytocin, and prostaglandin E2 release were analysed by reverse transcription-quantitative polymerase chain reaction, Trypan blue exclusion test, quantitative immunocytochemistry, and ELISA. Transfection of cells with miR-125b mimics inhibited cell viability, proliferation, apoptosis, the occurrence of FSHR, progesterone, testosterone, estradiol, and oxytocin release but stimulated prostaglandin E2 output. FSH promoted cell viability, proliferation, steroid hormones, IGF-I, oxytocin, and prostaglandin E2 output and reduced the expression of miR-125b and apoptosis. Furthermore, miR-125b mimics supported the effect of FSH on the release of estradiol, IGF-I, and prostaglandin E2, and inverted FSH influence on cell viability, proliferation, apoptosis, progesterone, and testosterone output. FSH supported both inhibitory and stimulatory action of miR-125b on ovarian cell functions. Present observations indicate that: miR-125b can be involved in the control of basic ovarian functions and that miR-125b and FSH are antagonists in their actions on ovarian cell functions. The ability of FSH to reduce miR-125b expression and the ability of miR-125b mimics to decrease the occurrence of FSHR and to modify FSH effects indicate the existence of the self-inhibiting FSH-miR-125b axis and that miR-125b can mediate the actions of FSH on ovarian cells.

Granulosa cells undergo BPA-induced apoptosis in a miR-21-independent manner

Bisphenol A (BPA) is a harmful endocrine disrupting compound that alters not only classical cellular mechanisms but also epigenetic mechanisms. Evidence suggests that BPA-induced changes in microRNA expression can explain, in part, the changes observed at both the molecular and cellular levels. BPA is toxic to granulosa cells (GCs) as it can activate apoptosis, which is known to contribute to increased follicular atresia. miR-21 is a crucial antiapoptotic regulator in GCs, yet the exact function in a BPA toxicity model remains unclear. BPA was found to induce bovine GC apoptosis through the activation of several intrinsic factors. BPA reduced live cells counts, increased late apoptosis/necrosis, increased apoptotic transcripts (BAX, BAD, BCL-2, CASP-9, HSP70), increased the BAX/Bcl-2 ratio and HSP70 at the protein level, and induced caspase-9 activity at 12 h post-exposure. miR-21 inhibition increased early apoptosis and, while it did not influence transcript levels or caspase-9 activity, it did elevate the BAX/Bcl-2 protein ratio and HSP70 in the same manner as BPA. Overall, this study shows that miR-21 plays a molecular role in regulating intrinsic mitochondrial apoptosis; however, miR-21 inhibition did not make the cells more sensitive to BPA. Therefore, apoptosis induced by BPA in bovine GCs is miR-21 independent.

Role and mechanism of miR-335-5p in the pathogenesis and treatment of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder of unknown etiology that occurs in women of reproductive age. Despite being considered to affect up to one-fifth of women in this cohort, the condition lacks generally accepted diagnostic biomarkers and options for targeted therapy. Hereby, we analyzed the diagnostic, therapeutic, and functional potential of a recently discovered miR-335-5p that was observed to be reduced in the follicular fluid (FF) of PCOS patients as compared with healthy women. We found miR-335-5p to be significantly decreased in the serum and FF samples of PCOS patients (n = 40) vs healthy women (n = 30), as well as in primary human granulosa cells (hGCs), and in 3 different hormonally induced PCOS-like murine models vs. wild-type (WT) mice. The level of circulating miR-335-5p was found to significantly correlate with the impaired endocrine and clinical features associated with PCOS in human patients. Ovarian intrabursal injection of the miR-335-5p antagomir in WT mice ovaries induced a PCOS-like reproductive phenotype. Treatment with the miR-335-5p agomir rescued the dihydrotestosterone-induced PCOS-phenotype in mice, thereby providing a functional link between miR-335-5p and PCOS. We identified SP1 as a miR-335-5p target gene by using the dual-luciferase reporter assay. Both the luciferase reporter assay and chromatin immunoprecipitation assay showed that SP1 bound to the promoter region of human CYP19A1 and inhibited its transcription. miR-335-5p increased the production of estradiol via the SP1/CYP19A1 axis in hGCs, thereby suggesting its mechanistic pathway of action. In conclusion, these results provide evidence that miR-335-5p may function as a mediator in the etiopathogenesis of PCOS, as well as has the potential as both a novel diagnostic biomarker and therapeutic target for PCOS.

Evaluation of the potential of miR-21 as a diagnostic marker for oocyte maturity and embryo quality in women undergoing ICSI

MicroRNAs are small molecules that play a crucial role in regulating a woman's reproductive system. The present study evaluates the expression of miR-21 in the serum, follicular fluid (FF), and cumulus cells (CCs) and their association with oocyte maturity and embryo quality in women undergoing intracytoplasmic sperm injection. Women subjects were divided into the case (54 Patients with female factor infertility) and control groups (33 patients with male factor infertility). The level of miR-21 was measured using Real-Time PCR. The level of miR-21 was significantly lower in the CCs, FF, and serum in the case compared to the control group (p < 0.05). MiR-21 abundance was higher in FF and CCs samples than in serum. Furthermore, there was a significant increase in CCs to FF in the case group (p < 0.05). A significant decrease in oocyte count, MII oocytes, and percentage of mature oocytes were observed in the case group (p < 0.05). The expression of miR-21 in FF and CCs was positively related to oocyte maturation, but no correlation with embryo development was observed. This study found that miR-21 is expressed less in women with female factor infertility, and human oocytes' development is crucially affected by the expression of miR-21. Therefore, miR-21 could provide new helpful biomarkers of oocyte maturity.