Higher PDCD4 expression is associated with obesity, insulin resistance, lipid metabolism disorders, and granulosa cell apoptosis in polycystic ovary syndrome

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

PDCD4 deficiency improved 4-vinylcyclohexene dioxide-induced mouse premature ovarian insufficiency

RESEARCH QUESTION

What role does programmed cell death 4 (PDCD4) play in premature ovarian insufficiency (POI)?

DESIGN

A PDCD4 gene knockout (PDCD4-/-) mouse model was constructed, a POI mouse model was established similar to human POI with 4-vinylcyclohexene dioxide (VCD), a PDCD4-overexpressed adenovirus was designed and the regulatory role in POI in vitro and in vivo was investigated.

RESULTS

PDCD4 expression was significantly increased in the ovarian granulosa cells of patients with POI (P ≤ 0.002 protein and mRNA) and mice with VCD-induced POI (P < 0.001 protein expression in both mouse ovaries and granulosa cells). In POI-induced mice model, PDCD4 knockouts significantly increased anti-Müllerian hormone, oestrodiol and numbers of developing follicles, and the PI3K-AKT-Bcl2/Bax signalling pathway is involved in it.

CONCLUSION

The expression and regulation of PDCD4 significantly affects the POI pathology in a mouse model. This effect is closely related to the regulation of Bcl2/Bax and the activation of the PI3K-AKT signalling pathway.

Role of circular RNA/miRNA axes in the pathophysiology of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a disorder resulted from interactions between genetic and environmental factors. Based on the importance of epigenetic factors in the pathoetiology of PCOS, the current review focused on identification of circular RNAs (circRNAs) that are involved in PCOS through acting as molecular sponges for microRNAs (miRNAs). The literature search led to identification of circ_0043533/miR-1179, circ_0030018/miR-136, circ_FURIN/miR-423-5p, circ-FURIN/miR-195-5p, circ_0043532/miR-182, circ_RANBP9/miR-136-5p, circRHBG/miR-515-5p, circMTO1/miR-320b, circASPH/miR-375, circPSMC3/miR-296-3p, circLDLR/miR-1294, circPUM1/miR-760, and hsa_circ_0118530/miR-136 as molecular axes contributing to the pathogenesis of PCOS. To set the stage for future research on the role of the ceRNA network in PCOS, in-silico analyses were performed using miRWalk, miRNet, and miRDIP databases. miRWalk identified 80 genes regulated by 5 miRNAs, miRNet revealed 6449 circRNAs potentially controlling 11 miRNAs, and miRDIP identified 11 miRNAs associated with 35 human pathways. These targets can be used in the treatment options, design of personalized medicine and prediction of prognosis of PCOS.

MiRNAs related in signaling pathways of women's reproductive diseases: an overview

BACKGROUND

One of the main health issues that can affect women's health is reproductive diseases, such as polycystic ovary syndrome (PCOS), endometriosis (EMs), uterine leiomyomas (ULs), and ovarian cancer (OC). Although these diseases are very common, we do not have a complete understanding of their underlying cellular and molecular mechanisms. It is important to mention that the majority of patients are diagnosed with these diseases at later stages because of the absence of early diagnostic techniques and dependable molecular indicators. Hence, it is crucial to discover novel and non-invasive biomarkers that have prognostic, diagnostic and therapeutic capabilities. MiRNAs, also known as microRNAs, are small non-coding RNAs that play a crucial role in regulating gene expression at the post-transcriptional level. They are short in length, typically consisting of around 22 nucleotides, and are highly conserved across species. Numerous studies have shown that miRNAs are expressed differently in various diseases and can act as either oncogenes or tumor suppressors.

METHODS

The author conducted a comprehensive review of all the pertinent papers available in web of science, PubMed, Google Scholar, and Scopus databases.

RESULTS

We achieved three goals: providing readers with better information, enhancing search results, and making peer review easier.

CONCLUSIONS

This review focuses on the investigation of miRNAs and their involvement in various reproductive disorders in women, including their molecular targets. Additionally, it explores the role of miRNAs in the development and progression of these disorders.

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

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

Altered histone abundance as a mode of ovotoxicity during 7,12-dimethylbenz[a]anthracene exposure with additive influence of obesity†

Histones are slowly evolving chromatin components and chromatin remodeling can incorporate histone variants differing from canonical histones as an epigenetic modification. Several identified histone variants are involved with the environmental stress-induced DNA damage response (DDR). Mechanisms of DDR in transcriptionally inactive, prophase-arrested oocytes and epigenetic regulation are under-explored in ovarian toxicology. The study objective was to identify ovarian proteomic and histone modifications induced by DMBA exposure and an influence of obesity. Post-pubertal wildtype (KK.Cg-a/a; lean) and agouti (KK.Cg-Ay/J; obese) female mice, were exposed to either corn oil (control; CT) or DMBA (1 mg/kg) for 7d via intraperitoneal injection (n = 10/treatment). Ovarian proteome analysis (LC-MS/MS) determined that obesity altered 225 proteins (P < 0.05) with histone 3 being the second least abundant (FC = -5.98, P < 0.05). Histone 4 decreased by 3.33-fold, histone variant H3.3 decreased by 3.05-fold, and H1.2, H1.4 and H1.1(alpha) variants increased by 1.59, 1.90 and 2.01-fold, respectively (P < 0.05). DMBA exposure altered 48 proteins in lean mice with no observed alterations in histones or histone variants. In obese mice, DMBA exposure altered 120 proteins and histone 2B abundance increased by 0.30-fold (P < 0.05). In DMBA-exposed mice, obesity altered the abundance of 634 proteins. Histones 4, 3 and 2A type 1-F decreased by 4.03, 3.71, 0.43-fold, respectively, whereas histone variant H1.2 and linker histone, H15 increased by 2.72- and 3.07-fold, respectively (P < 0.05). Thus, DMBA exposure alters histones and histone variants, and responsivity is more pronounced during obesity, potentially altering ovarian transcriptional regulation.

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.

Programmed cell death 4: A novel player in the pathogenesis of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a pathological condition recognized by menstrual cycle irregularities, androgen excess, and polycystic ovarian morphology, affecting a significant proportion of women of childbearing age and accounting for the most prevalent cause of anovulatory sterility. In addition, PCOS is frequently accompanied by metabolic and endocrine disturbances such as obesity, dyslipidemia, insulin resistance, and hyperinsulinemia, indicating the multiplicity of mechanisms implicated in the progression of PCOS. However, the exact pathogenesis of PCOS is yet to be elucidated. Programmed cell death 4 (PDCD4) is a ubiquitously expressed protein that contributes to the regulation of various cellular processes, including gene expression, cell cycle progression, proliferation, and apoptosis. Despite some disparities concerning its exact cellular effects, PDCD4 is generally characterized as a protein that inhibits cell cycle progression and proliferation and instead drives the cell into apoptosis. The apoptosis of granulosa cells (GCs) is speculated to take a major part in the occurrence and progression of PCOS by ceasing antral follicle development and compromising oocyte competence. Given the possible involvement of GC apoptosis in the progression of PCOS, as well as the contribution of PDCD4 to the regulation of cell apoptosis and the development of metabolic diseases, the current review aimed to discuss whether or how PDCD4 can play a role in the pathogenesis of PCOS by affecting GC apoptosis.

Regeneration and anti-inflammatory effects of stem cells and their extracellular vesicles in gynecological diseases

There are many gynecological diseases, among which breast cancer (BC), cervical cancer (CC), endometriosis (EMs), and polycystic ovary syndrome (PCOS) are common and difficult to cure. Stem cells (SCs) are a focus of regenerative medicine. They are commonly used to treat organ damage and difficult diseases because of their potential for self-renewal and multidirectional differentiation. SCs are also commonly used for difficult-to-treat gynecological diseases because of their strong directional differentiation ability with unlimited possibilities, their tendency to adhere to the diseased tissue site, and their use as carriers for drug delivery. SCs can produce exosomes in a paracrine manner. Exosomes can be produced in large quantities and have the advantage of easy storage. Their safety and efficacy are superior to those of SCs, which have considerable potential in gynecological treatment, such as inhibiting endometrial senescence, promoting vascular reconstruction, and improving anti-inflammatory and immune functions. In this paper, we review the mechanisms of the regenerative and anti-inflammatory capacity of SCs and exosomes in incurable gynecological diseases and the current progress in their application in genetic engineering to provide a foundation for further research.

The function of exosomes in ovarian granulosa cells

Granulosa cells (GCs), as the basic components of ovarian tissue, play an indispensable role in maintaining normal ovarian functions such as hormone synthesis and ovulation. The abnormality of GCs often leads to ovarian endocrine disorders, which exert a negative effect on life quality and life expectancy. However, the pathogenesis and treatment of diseases are still poorly understood. Exosomes contain regulatory molecules and can transmit biological information in cell interaction. The role of exosomes in GCs has been studied extensively. This review summarizes the regulatory function of exosomes in GCs, as well as their participation in etiopathogenesis and their promising application in treatment when it comes to ovarian endocrine diseases, which can help us better understand ovarian diseases from the perspective of GCs.

Integrated bioinformatics analysis elucidates granulosa cell whole-transcriptome landscape of PCOS in China

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common reproductive, neuroendocrine, and metabolic disorder in women of reproductive age that affects up to 5-10% of women of reproductive age. The aetiology of follicle development arrest and critical issues regarding the abnormal follicular development in PCOS remain unclear. The present study aims to systematically evaluate granulosa cell whole-transcriptome sequencing data to gain more insights into the transcriptomic landscape and molecular mechanism of PCOS in China.

METHODS

In the present study, the microarray datasets GSE138518, GSE168404, GSE193123, GSE138572, GSE95728, and GSE145296 were downloaded from the Gene Expression Omnibus (GEO) database. Subsequently, differential expression analysis was performed on the PCOS and control groups, followed by functional interaction prediction analysis to investigate gene-regulatory circuits in PCOS. Finally, hub genes and their associated ncRNAs were validated by qPCR in human-luteinized granulosa (hGL) cells and were correlated with the clinical characteristics of the patients.

RESULTS

A total of 200 differentially expressed mRNAs, 3 differentially expressed miRNAs, 52 differentially expressed lncRNAs, and 66 differentially expressed circRNAs were found in PCOS samples compared with controls. GO and KEGG enrichment analyses indicated that the DEGs were mostly enriched in phospholipid metabolic processes, steroid biosynthesis and inflammation related pathways. In addition, the upregulated miRNA hsa-miR-205-5p was significantly enriched in the ceRNA network, and two hub genes, MVD and PNPLA3, were regulated by hsa-miR-205-5p, which means that hsa-miR-205-5p may play a fundamental role in the pathogenesis of PCOS. We also found that MVD and PNPLA3 were related to metabolic processes and ovarian steroidogenesis, which may be the cause of the follicle development arrest in PCOS patients.

CONCLUSIONS

In summary, we systematically constructed a ceRNA network depicting the interactions between the ncRNAs and the hub genes in PCOS and control subjects and correlated the hub genes with the clinical characteristics of the patients, which provides valuable insights into the granulosa cell whole-transcriptome landscape of PCOS in China.

Acupuncture regulates the apoptosis of ovarian granulosa cells in polycystic ovarian syndrome-related abnormal follicular development through LncMEG3-mediated inhibition of miR-21-3p

BACKGROUND

The main features of polycystic ovary syndrome (PCOS) are abnormal follicular development and ovulatory dysfunction, which are caused by excessive apoptosis of ovarian granulosa cells. Acupuncture has been shown to improve follicular development abnormalities in patients with PCOS, but its mechanism is unknown. This study hypothesized that the mechanism of acupuncture on follicular development abnormalities in PCOS patients is the inhibition of granulosa cell apoptosis through LncMEG3-mediated regulation of miR-21-3p.

METHODS

A PCOS-like rat model was established using subcutaneous injection of dehydroepiandrosterone (DHEA). Acupuncture was performed on rats for 15 d (CV-4, RN-3, CV-6, SP-6 and EX-CA 1). Ovarian morphology was observed by HE staining, and sex hormone and AMH levels were detected by ELISA. Primary granulosa cells were isolated from each group of rats to assess the association of acupuncture treatment, LncMEG3, miR-21-3p, and granulosa cell apoptosis in rats with PCOS.

RESULTS

LncMEG3 and miR-21-3p were highly expressed in the ovarian granulosa cells of rats with PCOS, and LncMEG3-mediated regulation of miR-21-3p was involved in the development of PCOS in rats. Silencing of MEG3 attenuated sex hormone dysregulation and ovarian histopathological changes in PCOS rats and promoted follicle cell development and maturation. In addition, silencing MEG3 increased the viability and number of granulosa cells. In addition, silencing MEG3 further inhibited early and late apoptosis of ovarian granulosa cells in PCOS rats. Acupuncture improved polycystic ovarian morphology and sex hormone levels in PCOS rats. Acupuncture intervention increased the viability and number of granulosa cells. Acupuncture intervention inhibited early and late apoptosis of ovarian granulosa cells in PCOS rats by targeting miR-21-3p via LncMEG3.

CONCLUSION

These results suggest that acupuncture can downregulate LncMEG3, thereby targeting and regulating miR-21-3p to suppress early and late granulosa cell apoptosis and normalize their proliferation. These factors ultimately compensate for abnormal follicular development. These findings shed light on the clinical potential of acupuncture as a safe treatment for follicular developmental abnormalities in PCOS.

Exosomal microRNA-342-5p from human umbilical cord mesenchymal stem cells inhibits preeclampsia in rats

We aimed to investigate the inhibitory effect of human umbilical cord mesenchymal stem cell (hucMSC)-derived exosomes (hucMSC-Exos) transmitting microRNA-342-5p (miR-342-5p) on the development of preeclampsia (PE) by targeting programmed cell death 4 (PDCD4). The primary hucMSCs were cultured and transfected with miR-342-5p, and the exosomes (Exo) were extracted from the hucMSCs. PE rats were performed with an intraperitoneal injection of L-NAME from days 11 to 19 of gestation, and injection of Exo, Exo-negative control (NC), Exo-miR-342-5p agomir, Exo-miR-342-5p antagomir, and overexpressing PDCD4 (oe-PDCD4) vector into the placenta on the 16th day of pregnancy. HE staining was utilized to observe the pathological changes in placental tissues. TUNEL staining was implemented to evaluate cell apoptosis in placental tissues. Blood pressure and 24-h urinary protein in pregnant rats were measured by a non-invasive rat tail artery blood pressure measurement and protein auto-analyzer. Expressions of miR-342-5p, PDCD4, proinflammatory cytokines (TNF-α and IL-1β), and anti-inflammatory cytokines (IL-10 and TGF-β) were detected by RT-qPCR, and PDCD4 protein expression was determined by Western blot. The interaction between miR-342-5p and PDCD4 was analyzed by luciferase activity assay. MiR-342-5p was downregulated while PDCD4 was upregulated in the placental tissues of PE rats. HucMSC-Exo relieved pathology and suppressed inflammatory response, and apoptosis in the placental tissues, as well as reducing blood pressure and 24-h urinary protein of PE rats. Elevated miR-342-5p enhanced the promoting influence of hucMSC-Exo on PE rats, while inhibited miR-342-5p reversed the functions of hucMSC-Exo on PE rats. miR-342-5p targeted PDCD4. Overexpression of PDCD4 worsened the development of PE in rats. HucMSC-Exo conveying elevated miR-342-5p inhibits the development of PE in a rat model through downregulating PDCD4.

The molecular mechanism of miR-96-5p in the pathogenesis and treatment of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS), characterized by the androgen excess and arrest of antral follicles, is a common endocrine disorder among women lacking specific diagnostic biomarkers and therapeutic targets. Herein, we studied the molecular mechanism of miR-96-5p in the process of PCOS and its potential applications in PCOS. Clinically, we found that miR-96-5p significantly decreased in serum, follicular fluid and primary human granulosa cells (hGCs) of PCOS patients (n = 70) vs non-PCOS women (n = 60), as well as in the ovaries of 3-types of induced PCOS-like mice. Furthermore, we demonstrated that the elevated circulating miR-96-5p levels were significantly correlated with the PCOS disordered endocrine clinical features, and the area under the curve of receiver operating characteristic was 0.8344, with 75.71% specificity and 80% sensitivity. Mechanically, we identified miR-96-5p as an androgen-regulated miRNA that directly targets the forkhead transcription factor FOXO1. Inhibition of miR-96-5p decreased estrogen synthesis, while decreasing the cell proliferation index of KGN via regulating the expression of FOXO1 and its downstream genes. Inversely, inhibition of FOXO1 abrogated the effect of miR-96-5p on estrogen synthesis and proliferation index. Of note, ovarian intra-bursal injection of miR-96-5p agomir rescued the phenotypes of dehydroepiandrosterone-induced PCOS like mice. In conclusion, our results clarified a vital role of miR-96-5p in the pathogenesis of PCOS and might serve as a novel diagnostic biomarker and therapeutic target for PCOS.

Resveratrol improves follicular development of PCOS rats via regulating glycolysis pathway and targeting SIRT1

Polycystic ovary syndrome (PCOS) is a disease characterized by metabolic disorders. This study aimed to examine the effects of resveratrol treatment on ovulation in the PCOS rat model. Quantitative real-time PCR and immunohistochemistry were used to determine the mRNA and protein expression levels. TNUEL assay was used to evaluate cell apoptosis in ovary. The metabolites were evaluated by liquid chromatography with tandem mass spectrometry. Resveratrol alleviated disrupted estrous cycle and improved granular cell layers, and reversed the decreased proliferation and increased cell apoptosis of granulosa cells in the ovarian tissues of PCOS rats. Resveratrol restored the changes in the mRNA expression levels in the rate-limiting genes of glycolysis in the PCOS ovary. The expression of lactate dehydrogenase A (LDH-A), pyruvate kinase isozyme M2 (PKM2), and sirtuin 1 (SIRT1) was significantly downregulated in ovarian tissues of the PCOS rats; while the resveratrol treatment significantly increased the expression of LDH-A, PKM2, and SIRT1 in the ovarian tissues of PCOS rats. Collectively, the protective effects of resveratrol in the PCOS rats may be associated with the regulation of glycolysis-related mediators including PKM2, LDH-A, and SIRT1. Resveratrol may represent a good candidate in alleviating the development of PCOS.

Clinical efficacy of Wenjing decoction in the treatment of ovulatory disorder infertility: A systematic review and meta-analysis

OBJECTIVES

Wenjing decoction (WJD) was widely used in the treatment for ovulatory disorder infertility (ODI) in China, while its efficacy was not clearly known. In this study, we evaluated the clinical efficacy of WJD by meta-analysis.

METHODS

Eight electronic databases including Cochrane Library, PubMed, Embase, Web of Science, China National Knowledge Infrastructure, WanFang Data, VIP Database, and China Biology Medicine were searched for randomized controlled trials (RCTs) published from the inception of each database to July 1, 2021, of which the interventions involve WJD and clomiphene. Outcomes included clinical efficacy rate, pregnancy rate, ovulation rate, dominant follicle diameter, endometrial thickness, estradiol, follicle-stimulating hormone, and luteinizing hormone. Meta-analysis and risk of bias were performed by RevMan 5.3 software.

RESULTS

Eleven RCTs including 915 patients, of which 476 in the intervention group and 439 in the control group. Meta-analysis showed that WJD was better than clomiphene for patients with ODI in terms of clinical effective rate (odds ratio [OR] = 1.22, 95% confidence interval [CI]: 1.08-1.34), pregnancy rate (OR = 1.54, 95% CI: 1.15-2.07), ovulation rate (OR = 1.34, 95% CI: 1.07-1.67), endometrial thickness (mean difference [MD] = 1.50, 95% CI: 0.90-2.10), and dominant follicle diameter (MD = 1.85, 95% CI: 0.68-3.02). The estradiol level (MD = 91.0, 95% CI: 80.3-101.88) in patients taking WJD was significantly higher than those taking clomiphene, while the follicle-stimulating hormone level (MD = -0.93, 95% CI: -1.13 to -0.72) and the luteinizing hormone level (MD = -4.41, 95% CI: -4.80 to -4.03) in patients taking WJD was significantly lower than those taking clomiphene. Our results also indicated that WJD combined with clomiphene was better than clomiphene alone for patients with ODI in terms of pregnancy rate (OR = 1.79, 95% CI: 1.37-2.35).

CONCLUSIONS

WJD may be effective in the treatment of patients with ODI. Due to the quality and quantity of literature, RCT with large sample size and high quality need to be performed to verify our conclusion.

Pdcd4 promotes lipid deposition by attenuating PPARα-mediated fatty acid oxidation in hepatocytes

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive lipid accumulation in hepatocytes. The involvement of programmed cell death 4 (Pdcd4) in inflammation and metabolic diseases has been widely reported. However, the precise regulatory role of Pdcd4 in hepatocytic lipid metabolism and NAFLD is not well known.

RESEARCH DESIGN AND METHODS

We established a high-fat diet-induced NAFLD (HFD-NAFLD) rat model and a free fatty acids (FFAs)-treated cell model, and analyzed the expression and distribution of PDCD4. The lentivirus for Pdcd4 knockout and the vector for Pdcd4 overexpression were used to alter Pdcd4 expression in BRL 3A cells. Thereafter, lipid accumulation, FA metabolic gene expression, and peroxisome proliferator-activated receptor alpha (Pparα)-dependent peroxisomal β-oxidation-related gene expression, especially that of the critical transcription factors and enzymes acyl-CoA oxidases 1-3 (Acox1-3), were detected both at the mRNA and protein levels.

RESULTS

PDCD4 expression increased and it was mainly distributed in hepatocyte nuclei of the HFD-NAFLD rats. as well as the FFAs-treated CBRH-7919 and BRL 3A cell lines. Pdcd4 knockout significantly suppressed FFAs-induced lipid accumulation, and Pdcd4 overexpression accelerated FFAs-induced lipid accumulation in hepatocytes. Mechanistically, Pdcd4 negatively regulated the expression Pparα and Acox1-3. In addition, rescue experiments confirmed that Pparα knockdown could attenuate the expression of Acox1-3 in Pdcd4 knockout cells, which ultimately restored lipid deposition to normal levels. PPARα expression decreased in the liver of the HFD-NAFLD rats. The enrichment of PDCD4 in hepatocyte nuclei correlated with lower PPARα expression after FFAs treatment in vitro.

CONCLUSION

Our results indicate that the abundance of PDCD4 under high-fat conditions facilitates hepatocellular lipid accumulation by decreasing PPARα-dependent FA peroxisomal β-oxidation.

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

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

Coculture of porcine luteal cells during in vitro porcine oocyte maturation affects blastocyst gene expression and developmental potential

Oocyte maturation in culture is still the weakest part of in vitro fertilization (IVF) and coculture with somatic cells may be an alternative to improve suboptimal culture conditions, especially in the pig in which maturation takes more than 44 h. In the present study, we investigated the effect of a coculture system of porcine luteal cells (PLC) during in vitro maturation (IVM) on embryo development and gene expression. Cumulus-oocyte complexes were matured in vitro in TCM-199 with human menopausal gonadotrophin (control) and in coculture with PLC. IVF was performed with frozen-thawed boar semen in Tris-buffered medium. Presumptive zygotes were cultured in PZM for 7 days. The coculture with PLC significantly increased blastocysts rates. Gene expression changes were measured with a porcine embryo-specific microarray and confirmed by RT-qPCR. The global transcription pattern of embryos developing after PLC coculture exhibited overall downregulation of gene expression. Following global gene expression pattern analysis, genes associated with lipid metabolism, mitochondrial function, endoplasmic reticulum stress, and apoptosis were found downregulated, and genes associated with cell cycle and proliferation were found upregulated in the PLC coculture. Canonical pathway analysis by Ingenuity Pathway revealed that differential expression transcripts were associated with the sirtuin signaling pathway, oxidative phosphorylation pathway, cytokines and ephrin receptor signaling. To conclude, the coculture system of PLC during IVM has a lasting effect on the embryo until the blastocyst stage, modifying gene expression, with a positive effect on embryo development. Our model could be an alternative to replace the conventional maturation medium with gonadotrophins with higher rates of embryo development, a key issue in porcine in vitro embryo production.

The role of miRNAs in polycystic ovary syndrome with insulin resistance

PURPOSE

This review aims to summarize the key findings of several miRNAs and their roles in polycystic ovary syndrome with insulin resistance, characterize the disease pathogenesis, and establish a new theoretical basis for diagnosing, treating, and preventing polycystic ovary syndrome.

METHODS

Relevant scientific literature was covered from 1992 to 2020 by searching the PubMed database with search terms: insulin/insulin resistance, polycystic ovary syndrome, microRNAs, and metabolic diseases. References of relevant studies were cross-checked.

RESULTS

The related miRNAs (including differentially expressed miRNAs) and their roles in pathogenesis, and possible therapeutic targets and pathways, are discussed, highlighting controversies and offering thoughts for future directions.

CONCLUSION

We found abundant evidence on the role of differentially expressed miRNAs with its related phenotypes in PCOS. Considering the essential role of insulin resistance in the pathogenesis of PCOS, the alterations of associated miRNAs need more research attention. We speculate that race/ethnicity or PCOS phenotype and differences in methodological differences might lead to inconsistencies in research findings; thus, several miRNA profiles need to be investigated further to qualify for the potential therapeutic targets for PCOS-IR.

Long non-coding RNA lnc-CCNL1-3:1 promotes granulosa cell apoptosis and suppresses glucose uptake in women with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disease in premenopausal women. Long non-coding RNAs (lncRNAs) constitute important factors in numerous biological processes. However, their roles in PCOS pathogenesis require further clarification. Our study aims to elucidate the roles of lncRNA lnc-CCNL1-3:1 (CCNL) in PCOS. CCNL expression in human luteinized granulosa cells (hLGCs) derived from women with and without PCOS was detected. The full length of CCNL was obtained by 5' and 3' rapid amplification of cDNA ends. CCNL roles in granulosa cell apoptosis, mitochondrial function, and glucose uptake were evaluated. The binding relationship between CCNL and forkhead box O1 (FOXO1) was determined by RPISeq, RNA immunoprecipitation, subcellular fractionation, and immunofluorescence. In KGN cells and hLGCs, CCNL overexpression upregulated FOXO1 expression, promoted cell apoptosis, reduced glucose transport capability, and impaired mitochondrial function, and these effects were partially abolished by silencing FOXO1. The interaction of CCNL with FOXO1 might prevents FOXO1 exclusion from the nucleus and subsequent degradation in the cytosol. We determined that CCNL serve as a facilitator in the processes of PCOS. CCNL might participate in PCOS pathologies such as follicular atresia and insulin resistance.

Programmed cell death factor 4 (PDCD4), a novel therapy target for metabolic diseases besides cancer

Programmed cell death factor 4 (PDCD4) is originally described as a tumor suppressor gene that exerts antineoplastic effects by promoting apoptosis and inhibiting tumor cell proliferation, invasion, and metastasis. Several investigations have probed the aberrant expression of PDCD4 with the progression of metabolic diseases, such as polycystic ovary syndrome (PCOS), obesity, diabetes, and atherosclerosis. It has been ascertained that PDCD4 causes glucose and lipid metabolism disorders, insulin resistance, oxidative stress, chronic inflammatory response, and gut flora disorders to regulate the progression of metabolic diseases. This review aims to summarize the latest researches to uncover the structure, expression regulation, and biological functions of PDCD4 and to elucidate the regulatory mechanism of the development of tumors and metabolic diseases. This review has emphasized the understanding of the PDCD4 role and to provide new ideas for the research, diagnosis, and treatment of tumors and metabolic diseases.

Rosiglitazone ameliorates palmitic acid-induced endoplasmic reticulum stress and steroidogenic capacity in granulosa cells

Granulosa cells play essential roles in follicular development, oocyte maturation and sex hormone secretion. The exposure of granulosa cells to palmitic acid (PA), the main component of dietary saturated fat, inhibits cell viability. However, the mechanism underlying PA-induced cytotoxicity in granulosa cells has not been deeply investigated. Rosiglitazone (RSG) is a member of the thiazolidinedione family and is reported to protect cells from cytotoxicity and endoplasmic reticulum (ER) stress in other cell types, but whether RSG protects granulosa cells remain unknown. In this study, KGN cell line and primary granulosa cells were used as models of granulosa cells to explore the effects of PA and RSG and the underlying mechanisms. The results showed that PA inhibits cell viability and estradiol secretion through inducing ER stress and cAMP/PKA/CREB pathway. CCAAT/enhancer-binding protein homologous protein (CHOP), an ER stress marker, was demonstrated to participate in PA-induced cytotoxicity. RSG treatment rescued granulosa cells from PA-induced cell death and ER stress. Moreover, RSG was identified to ameliorate ER stress induced by tunicamycin in granulosa cells. In addition, RSG treatment rescued granulosa cells from PA-induced decrease of estrogen secretion by cAMP/PKA/CREB pathway. In conclusion, RSG can protect granulosa cells against PA-induced cytotoxicity by inhibiting ER stress, and can recover steroidogenic capacity, indicating a potential use of RSG in the treatment of granulosa cell dysfunction.

Combined use of Diane-35 and metformin improves the ovulation in the PCOS rat model possibly via regulating glycolysis pathway

BACKGROUND

Polycystic ovary syndrome (PCOS) is a complex endocrine and metabolic disease with unknown pathogenesis. However, the treatment of Diane-35 combined with metformin can improve the endocrine and ovulation of PCOS. In this study, we investigated the effects of Diane-35 combined with metformin (DM) treatment on ovulation and glucose metabolism in a PCOS rat model.

METHODS

Sprague Dawley rats were divided into 3 groups, control group, model group (PCOS group) and Diane-35 combined with metformin (PCOS + DM group). The mRNA expression levels were determined by qRT-PCR. The hormone levels were determined by enzyme-linked immunosorbent assay. Immunostaining detected the protein levels of lactate dehydrogenase A (LDH-A), pyruvate kinase isozyme M2 (PKM2) and sirtuin 1 (SIRT1) in the ovarian tissues. TNUEL assay was performed to determine cell apoptosis in the PCOS rats. The metabolites in the ovarian tissues were analyzed by liquid chromatography with tandem mass spectrometry.

RESULTS

PCOS rats showed an increased in body weight, levels of luteinizing hormone and testosterone and insulin resistance, which was significantly attenuated by the DM treatment. The DM treatment improved disrupted estrous cycle and increased the granulosa cells of the ovary in the PCOS rats. The decreased proliferation and increased cell apoptosis of granulosa cells in the ovarian tissues of PCOS rats were significantly reversed by the DM treatment. The analysis of metabolics revealed that ATP and lactate levels were significantly decreased in PCOS rats, which was recovered by the DM treatment. Furthermore, the expression of LDH-A, PKM2 and SIRT1 was significantly down-regulated in ovarian tissues of the PCOS rats; while the DM treatment significantly increased the expression of LDH-A, PKM2 and SIRT1 in the ovarian tissues of the PCOS rats.

CONCLUSION

In conclusion, our study demonstrated that Diane-35 plus metformin treatment improved the pathological changes in the PCOS rats. Further studies suggest that Diane-35 plus metformin can improve the energy metabolism of the ovary via regulating the glycolysis pathway. The mechanistic studies indicated that the therapeutic effects of Diane-35 plus metformin treatment in the PCOS rats may be associated with the regulation of glycolysis-related mediators including PKM2, LDH-A and SIRT1.

Fractalkine and apoptotic/anti-apoptotic markers in granulosa cells of women with polycystic ovarian syndrome

Owing to the role of fractalkine in regulating cellular apoptosis/proliferation, we investigated fractalkine effects on apoptosis/proliferation signaling of granulosa cells in polycystic ovarian syndrome (PCOS) patients through in vitro and in vivo experiments. In vivo, granulosa cells were collected from 40 women undergoing oocyte retrieval (20 controls and 20 PCOS). The expression levels of fractalkine, BAX, Bcl2, Bcl2-XL, Bad, and TNF-α were assessed using RT-PCR. In vitro, we determined the effect of different doses of fractalkine on the expression of the above mentioned genes in GCs of both groups. We found that the expression levels of fractalkine and Bcl-2 were significantly lower in the GCs of PCOS patients compared to the control group (p < 0.05). In contrast, the expression levels of TNF-α and BAX were higher in the patient's group than in the control group. The results suggested that expression levels of fractalkine were negatively and positively correlated with the number of oocytes and fertilized oocytes respectively. Moreover, fractalkine could dose-dependently increase fractalkine and decrease BAD, BAX, Bcl-xl, and TNF-α expressions in the control GCs. In contrast, GCs collected from PCOS patients revealed an increase in expression of BAD, BAX, and Bcl-xl following fractalkine treatment. Our findings indicated that insufficient expression of fractalkine in PCOS patients is related with elevated apoptotic and inflammatory markers and reduced anti-apoptotic genes in the GCs.

Hyperandrogen enhances apoptosis of human ovarian granulosa cells via up-regulation and demethylation of PDCD4

Apoptosis of granulosa cells (GCs) induced by hyperandrogen plays a key role in the pathogenesis of polycystic ovary syndrome (PCOS). However, the mechanism of androgen-induced apoptosis of GCs has not been clarified to date. Recent studies have reported that PDCD4 expression is higher in PCOS patients and might be a key factor in PCOS progression. In this study, we aimed to investigate the role of PDCD4 in regulating apoptosis of human GCs and whether hyperandrogen regulate PDCD4 expression through DNA methylation. Overexpression of PDCD4 in human ovarian granulosa cell line KGN cells promoted cells apoptosis. Meanwhile, expression of caspase-3 and caspase-9 were significantly elevated. High concentration of testosterone treatment resulted in up-regulation of PDCD4 and a significant increase of apoptosis in KGN cells. In addition, knockdown of PDCD4 in KGN cells treated with high concentration of testosterone abolished the hyperandrogen-induced apoptosis. Furthermore, high concentration of testosterone down-regulated DNMT1, DNMT3A and DNMT3B expression and the methylation level in the promoter region of PDCD4 was decreased. In conclusion, PDCD4 can promote apoptosis of human ovarian GCs. The mechanism of hyperandrogen-induced apoptosis may be mediated by PDCD4. Furthermore, the up-regulation of PDCD4 induced by hyperandrogen may through demethylation of its promoter regions.

Mesenchymal stem cells derived exosomal miR-323-3p promotes proliferation and inhibits apoptosis of cumulus cells in polycystic ovary syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a heterogeneous reproductive disease. Adipose mesenchymal stem cells (AMSCs) can produce a mass of exosomes. The objective of this study was to determine the effects of exosomal miR-323-3p on cumulus cells (CCs) of PCOS patients. Exosomal miR-323-3p were collected from modified AMSCs. Real-time PCR, western blots, MTT assays, flow cytometry, luciferase reporter assays and a letrozole-induced PCOS mouse model were used to identify mechanisms of exosomal miR-323-3p on CCs. The results revealed that miR-323-3p expression was upregulated in AMSCs, exosomes and CCs. Upregulated miR-323-3p promoted cell proliferation and suppressed apoptosis in CCs, while miR-323-3p inhibitor exerted opposite roles in exosome-treated CCs. Moreover, PDCD4 was upregulated in PCOS CCs, displayed an inverse expression pattern to those of miR-323-3p, and was a direct target of miR-323-3p. Overexpression of PDCD4 reversed the effects of upregulated miR-323-3p on CCs. Serum FSH, LH and testosterone were upregulated while E2 levels were downregulated in the PCOS mice. Upregulation of miR-323-3p alleviated PCOS by suppressing CCs' apoptosis through targeting PDCD4 in vivo. The results demonstrated that exosomal miR-323-3p promoted cell proliferation and inhibited apoptosis in CCs through targeting PDCD4 in PCOS. This study provides insight into developing new therapeutic strategies for PCOS.

Ovarian mitochondrial dynamics and cell fate regulation in an androgen-induced rat model of polycystic ovarian syndrome

In this study, we investigated in an androgenized rat model the involvement of autophagy and mitochondrial dynamics in granulosa cells in the pathogenesis of polycystic ovarian syndrome (PCOS) and its modulation by exogenous gonadotropin (eCG). We found 5α-dihydrotestosterone (DHT) treatment reduces ovarian length and weight with predominantly late antral and/or preovulatory stage follicles and no corpora lutea. DHT increased the population of large lysosomes (>50 micron) and macroautophagy, an event associated with granulosa cell apoptosis. Increased granulosa cell Dynamin Related Protein 1 (Drp1) content in the DHT group was accompanied by increased circular and constricted, but reduced rod-shaped, mitochondria. eCG eliminated all atypical follicles and increased the number of late antral and preovulatory follicles with less granulosa cell apoptosis. eCG-treated rats had a higher proportion of connected mitochondria, and in combination with DHT had a lower proportion of circular and constricted mitochondria than rats treated with DHT alone, suggesting that eCG induces mitochondrial fusion and attenuates fission in granulosa cells. In summary, we observed that DHT-induced up-regulation of Drp1 is associated with excessive mitochondrial fission, macroautophagy and apoptosis in granulosa cells at the antral stage of development in an androgenized rat model for PCOS, a response partially attenuated by exogenous gonadotropin.

Dendrobium nobile Lindl. polysaccharides improve follicular development in PCOS rats

Polycystic ovary syndrome (PCOS) is the most typical and common metabolic abnormalities in women of reproductive age. This study examined the protective effects of Dendrobium nobile Lindl. polysaccharides (DNLP) on ovarian follicular development in letrozole-induced PCOS rats and explored the underlying molecular mechanisms. The PCOS rats showed the increased body weight, serum testosterone and luteinizing hormone levels and insulin resistance. DNLP treatment reduced the body weight, serum testosterone level and insulin resistance, but failed to affect luteinizing hormone level in the PCOS rats. DNLP treatment recovered disrupted estrous cycle in the PCOS rats. DNLP treatment decreased antral follicles and increased the thickness of the granular cell layer. DNLP treatment increased the PCNA mRNA and protein expression levels in the PCOS ovarian tissues, and inhibited cell apoptosis in the PCOS ovarian tissues via regulating apoptosis-related proteins including Bax, Bcl-2 and caspase-3. In summary, this study demonstrated the protective effects of DNLP on the ovaries in the letrozole-induced PCOS rat model. DNLP exerted its protective effects via improving follicular development and inhibiting apoptosis of ovarian granular cells in PCOS rats. This study will provide experimental basis for the future clinical application of DNLP in the treatment of PCOS.

Lipotoxicity Impairs Granulosa Cell Function Through Activated Endoplasmic Reticulum Stress Pathway

Obesity is closely related to reproductive disorders, which may eventually lead to infertility in both males and females. Ovarian granulosa cells play a critical role during the maintenance of oocyte development through the generation of sex steroids (mainly estradiol and progesterone) and different kinds of growth factors. However, the molecular mechanism of obesity-induced granulosa cell dysfunction remains poorly investigated. In our current study, we observed that high-fat diet feeding significantly increased the level of glucose-regulated protein 78 kDa (GRP78) protein expression in mouse granulosa cells; testosterone-induced estradiol generation was impaired accordingly. To further evaluate the precise mechanism of lipotoxicity-induced granulosa cell dysfunction, mouse primary granulosa cells were treated with palmitate, and the expression levels of ER stress markers were evaluated by real-time PCR and western blot. Lipotoxicity significantly increased ER stress but impaired the mRNA expression of granulosa cell function-related makers, including androgen receptor (Ar), cytochrome P450 family 19 subfamily A member 1 (Cyp19a1), hydroxysteroid 17-beta dehydrogenase 1 (Hsd17b1), and insulin receptor substrate 1 (Irs1). Impaired testosterone-induced estradiol generation was also observed in cultured mouse granulosa cells after palmitate treatment. Insulin augmented testosterone induced estradiol generation through activation of the AKT pathway. However, palmitate treatment abolished insulin-promoted aromatase expression and estradiol generation by the stimulation of ER stress. Overexpression of IRS1 significantly ameliorated palmitate- or tunicamycin-induced impairment of aromatase expression and estradiol generation. Taken together, our current study demonstrated that lipotoxicity impaired insulin-stimulated estradiol generation through activated ER stress and inhibited IRS1 pathway.

Dietary α-Linolenic Acid-Rich Flaxseed Oil Exerts Beneficial Effects on Polycystic Ovary Syndrome Through Sex Steroid Hormones-Microbiota-Inflammation Axis in Rats

Polycystic ovary syndrome (PCOS) represents a common endocrine-metabolic disorder disease with chronic low-grade inflammation and alteration of intestinal flora. Serving as functional food, flaxseed oil (FO), which is rich in plant-derived α-linolenic acid of omega-3 polyunsaturated fatty acids, has been proven to benefit for chronic metabolic diseases. However, the exact role of dietary FO on PCOS remains largely unclear. In the present study, 6-week-old female Sprague-Dawley rats were randomly divided into four groups (eight rats/group), including (a) pair-fed (PF) control (CON) group (PF/CON), (b) FO-fed CON group (FO/CON), (c) PF with letrozole-induced PCOS model (MOD) group (PF/MOD), and (d) FO-fed MOD group (FO/MOD). All rats were fed a standard diet. After 3 weeks of modeling and subsequent 8 weeks of treatment, the rats in diverse groups were euthanized and associated indications were investigated. The results showed that dietary FO ameliorated the disorder of estrous cycle and ovarian morphology. In parallel, dietary FO improved the sex steroid hormone disturbance (luteinizing hormone/follicle-stimulating hormone, estrogen, testosterone, and progesterone), body weights, dyslipidemia, and insulin resistance. Moreover, FO treatment improved plasma and ovary inflammatory interleukin (IL)-1β, IL-6, IL-10, and IL-17A, tumor necrosis factor-α, and monocyte chemoattractant protein-1. Additionally, FO intervention significantly modulated the composition of gut microbiota and vaginal microbiota by increasing the abundances of Allobaculum, Lactobacillus, Butyrivibrio, Desulfovibrio, Bifidobacterium, Faecalibacterium, Parabacteroides as well as decreasing the abundances of Actinobacteria, Bacteroides, Proteobacteria, and Streptococcus, the ratio of Firmicutes/Bacteroidetes. A decrease in plasma lipopolysaccharide level and an increase in short-chain fatty acids, including acetic acid, propionic acid, butyric acid and pentanoic acid, were determined after dietary FO supplementation. Correlation analysis revealed close relationships among sex steroid hormones, inflammation, and gut/vaginal microbiota. Collectively, this study demonstrated that dietary FO ameliorated PCOS through the sex steroid hormones-microbiota-inflammation axis in rats, which may contribute to the understanding of pathogenesis and potentially serve as an inexpensive intervention in the control of PCOS.

Characteristics of obesity in polycystic ovary syndrome: Etiology, treatment, and genetics

Polycystic ovary syndrome (PCOS) has multiple etiologies including ovarian and adrenal hyperandrogenism, neuro-endocrine and hypothalamic-pituitary dysfunction, and disorders of peripheral insulin resistance. Obesity is neither necessary nor sufficient for the PCOS phenotype, and the association of PCOS with obesity is not universal, with national, cultural, and ethnic differences. Obesity, particularly visceral adiposity which is common in obese and non-obese women with PCOS, amplifies and worsens all metabolic and reproductive outcomes in PCOS. Obesity increases insulin resistance and compensatory hyperinsulinemia, which in turn increases adipogenesis and decreases lipolysis. Obesity sensitizes thecal cells to LH stimulation and amplifies functional ovarian hyperandrogenism by upregulating ovarian androgen production. Obesity increases inflammatory adipokines which, in turn, increase insulin resistance and adipogenesis. Lifestyle interventions focused on diet-weight loss and concurrent exercise are central to therapy which also commonly subsequently needs to include pharmacologic therapy. PCOS symptoms commonly improve with 5% to 10% weight loss, but 25% to 50% weight loss, usually achievable only through bariatric surgery, may be required for morbid obesity unresponsive to lifestyle-medical treatment. Bariatric surgery is a valuable approach to weight loss in PCOS where BMI is ≥40 kg/m² when non-surgical treatment and/or induction of pregnancy have failed, and can be an initial treatment when BMI is ≥50 kg/m². Further research in PCOS is needed to better understand the fundamental basis of the disorder, to ameliorate obesity, to correct hyperandrogenism, ovulation, hyperinsulinemia, and to optimize metabolic homeostasis.

miR-323-3p regulates the steroidogenesis and cell apoptosis in polycystic ovary syndrome (PCOS) by targeting IGF-1

Polycystic ovary syndrome (PCOS) is an endocrine and metabolic heterogeneous disorder. The incidence of which reaches 5% to 10% among reproductive-age women. Abnormal folliculogenesis is considered to be a common characteristic of PCOS, but the cause of this disorder and its pathogenesis still remain uncertain. Previous studies had proved that dysregulation of microRNAs is related to the pathogenesis of PCOS. In this study, we investigated the effect of miR-323-3p on the human cumulus cells (CCs). We also investigated the underlying mechanisms of miR-323-3p on human granulosa-like tumor cell line (KGN) or primary human CCs by stimulating with Dihydrotestosterone (DHT). Our findings suggested that the level of miR-323-3p in human CCs of women with PCOS was down-regulated, compared with that of the control group. Moreover, the inhibition of the level of miR-323-3p could up-regulate of the steroidogenesis and promote the apoptosis in KGN cells. In addition, our data confirmed that the Insulin-like growth factor 1 (IGF-1) gene was the direct target of miR-323-3p. Furthermore, the mimic of miR-323-3p inhibited the expression of IGF-1, which down-regulated the levels of AR, AMHR-II, CYP19A, EGFR, and GATA-4. In conclusion, miR-323-3p targeting IGF-1 regulates the steroidogenesis and the activity of CCs, which plays an important role in the occurrence and development of PCOS. Our results have shown that miR-323-3p is a novel and promising molecular target for the improvement of the dysfunction of CCs in PCOS.

STAT3 signaling stimulates miR-21 expression in bovine cumulus cells during in vitro oocyte maturation

MicroRNAs are potent regulators of gene expression that have been widely implicated in reproduction and embryo development. Recent studies have demonstrated that miR-21, a microRNA extensively studied in the context of disease, is important in multiple facets of reproductive biology including folliculogenesis, ovulation, oocyte maturation and early mammalian development. Surprisingly, little is known about the mechanisms that regulate miR-21 and no studies have characterized these regulatory pathways in cumulus-oocyte complexes (COCs). We therefore investigated miR-21 in an in vitro model of bovine oocyte maturation. Levels of the primary transcript of miR-21 (pri-miR-21) and mature miR-21 increased markedly in COCs over the maturation period. Cloning of the bovine pri-miR-21 gene and promoter by 5′3′RACE (rapid amplification of cDNA ends) revealed a highly conserved region immediately upstream of the transcription start site and two alternatively-spliced variants of pri-miR-21. The promoter region contained several putative transcription factor binding sites, including two for signal transducer and activator of transcription 3 (STAT3). Mutation of these sites significantly decreased both the intrinsic activity of pri-miR-21 promoter-luciferase constructs and the response to leukemia inhibitory factor (LIF) (a STAT3 activator) in cultured MCF7 cells. In COCs, treatment with a STAT3 pathway inhibitor markedly decreased pri-miR-21 expression and prevented cumulus expansion. Pri-miR-21 expression was also inhibited by the protein synthesis inhibitor cycloheximide, suggesting that a protein ligand or signaling cofactor synthesized during maturation is necessary for transcription. Together these studies represent the first investigation of signaling pathways that directly influence miR-21 expression in bovine oocytes and cumulus cells.

Expression and function of Pdcd4 in mouse endometrium during early pregnancy

Embryo implantation is a complex process involving synchronised crosstalk between a receptive endometrium and functional blastocysts. Apoptosis plays an important role in this process as well as in the maintenance of pregnancy. In this study, we analysed the expression pattern of programmed cell death 4 (Pdcd4), a gene associated with apoptosis in the mouse endometrium, during early pregnancy and pseudopregnancy by real-time quantitative polymerase chain reaction, in situ hybridisation, Western blotting and immunohistochemistry. The results showed that Pdcd4 was increased along with days of pregnancy and significantly reduced at implantation sites (IS) from day 5 of pregnancy (D5). The level of Pdcd4 at IS was substantially lower than that at interimplantation sites (IIS) on D6 and D7. In addition, Pdcd4 expression in the endometrium was reduced in response to artificially induced decidualisation in vivo and in vitro. Downregulation of Pdcd4 gene expression in cultured primary stromal cells promoted decidualisation, while upregulation inhibited the decidualisation process by increasing apoptosis. These results demonstrate that Pdcd4 is involved in stromal cell decidualisation by mediating apoptosis and therefore plays a role in embryo implantation in mice.

Variation in the α2A-adrenergic receptor gene and risk of gestational diabetes

AIM

Sympathetic activation suppresses insulin secretion via pancreatic ADRA2A.  Because sympathetic activity and insulin demand increase during pregnancy, we tested the hypothesis  that ADRA2A variants are associated with gestational diabetes (GDM).

PATIENTS & METHODS

Among Caucasian pregnant women without pre-existing diabetes, we genotyped 458 who had GDM and 1537 without GDM for seven ADRA2A variants.

RESULTS

rs1800038 (OR: 2.34; p = 0.020) and rs3750625 (OR: 1.56; p = 0.010) increased the risk of GDM, and rs11195418 decreased it (OR: 0.62; p = 0.025). The associations remained significant after adjustment for maternal age, maternal BMI, parity and a genetic risk score that included variants previously associated with Type 2 diabetes mellitus and GDM.

CONCLUSION

ADRA2A genetic variation contributes independently to the risk of GDM in Caucasian women.

Abnormality of Klotho Signaling Is Involved in Polycystic Ovary Syndrome

This study investigated the involvement of the klotho-associated signaling in the apoptosis of granulosa cells (GCs) from the ovaries of patients with polycystic ovary syndrome (PCOS) and PCOS animals. Primary GCs were obtained from 26 healthy women and 43 women with PCOS. The PCOS animal model was established by the injection of dehydroepiandrosterone (DHEA). Klotho protein and associated microRNA expression in human primary GCs and rats' ovarian tissues were measured by Western blot and real-time polymerase chain reaction, respectively. Results showed that significantly lower miR-126-5p and miR-29a-5p microRNA expressions, higher klotho protein expression, lower insulin growth factor 1 (IGF-1R) and Wnt family member 1 (Wnt1) protein expressions, and lower Akt phosphorylation at Ser⁴⁷³ and Thr³⁰⁸ residues were observed in the GCs from patients with PCOS and the ovarian tissues of PCOS rats compared to that in GCs from healthy women and ovarian tissues of normal control rats, respectively. Knockdown of klotho gene expression normalized IGF-1R and Wnt1 protein expressions and Akt phosphorylation in GCs from patients with PCOS and the ovarian tissues from PCOS rats; it also blocked the effects of insulin on apoptosis and proliferation in GCs from patients with PCOS and inhibited caspase-3 activity in ovarian tissues of PCOS rats. Knockdown of klotho gene expression increased the pregnancy rate in DHEA-treated female rats and increased the body weight of their newborns through normalizing the ovarian function and decreasing the formation of cystic follicles. In conclusion, the miR-126-5p, miR-29a-5p/klotho/insulin-IGF-1, Wnt, and Akt signal pathway may be involved in the apoptosis of GCs and subsequent development of PCOS.

A Network Pharmacology Approach to Explore the Pharmacological Mechanism of Xiaoyao Powder on Anovulatory Infertility

Aim. To explore the pharmacological mechanism of Xiaoyao powder (XYP) on anovulatory infertility by a network pharmacology approach. Method. Collect XYP's active compounds by traditional Chinese medicine (TCM) databases, and input them into PharmMapper to get their targets. Then note these targets by Kyoto Encyclopedia of Genes and Genomes (KEGG) and filter out targets that can be noted by human signal pathway. Get the information of modern pharmacology of active compounds and recipe's traditional effects through databases. Acquire infertility targets by Therapeutic Target Database (TTD). Collect the interactions of all the targets and other human proteins via String and INACT. Put all the targets into the Database for Annotation, Visualization, and Integrated Discovery (DAVID) to do GO enrichment analysis. Finally, draw the network by Cytoscape by the information above. Result. Six network pictures and two GO enrichment analysis pictures are visualized. Conclusion. According to this network pharmacology approach some signal pathways of XYP acting on infertility are found for the first time. Some biological processes can also be identified as XYP's effects on anovulatory infertility. We believe that evaluating the efficacy of TCM recipes and uncovering the pharmacological mechanism on a systematic level will be a significant method for future studies.

Transcription factor‑microRNA synergistic regulatory network revealing the mechanism of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common type of endocrine disorder, affecting 5–11% of women of reproductive age worldwide. Transcription factors (TFs) and microRNAs are considered to have crucial roles in the developmental process of several diseases and have synergistic regulatory actions. However, the effects of TFs and microRNAs, and the patterns of their cooperation in the synergistic regulatory network of PCOS, remain to be elucidated. The present study aimed to determine the possible mechanism of PCOS, based on a TF-microRNA synergistic regulatory network. Initially, the differentially expressed genes (DEGs) in PCOS were identified using microarray data of the GSE34526 dataset. Subsequently, the TFs and microRNAs which regulated the DEGs of PCOS were identified, and a PCOS-associated TF-microRNA synergistic regulatory network was constructed. This network included 195 DEGs, 136 TFs and 283 microRNAs, and the DEGs were regulated by TFs and microRNAs. Based on topological and functional enrichment analyses, SP1, mir-355-5p and JUN were identified as potentially crucial regulators in the development of PCOS and in characterizing the regulatory mechanism. In conclusion, the TF-microRNA synergistic regulatory network constructed in the present study provides novel insight on the molecular mechanism of PCOS in the form of synergistic regulated model.