3D hUC-MSC spheroids exhibit superior resistance to autophagy and apoptosis of granulosa cells in POF rat model.

In brief: This study reveals that orthotopic transplantation of 3D hUC-MSC spheroids is more effective than monolayer-cultured hUC-MSCs in improving POF and distinctly reducing oxidative stress through the paracrine effect, thereby preventing apoptosis and autophagy of GCs. Abstract: Premature ovarian failure (POF) is a common reproductive disease in women younger than 40 years old, and studies have demonstrated that the application of human umbilical cord mesenchymal stem cells (hUC-MSCs) is a promising therapy strategy for POF. Given the previously established therapeutic advantages of 3D MSC spheroids, and to evaluate their effectiveness, both 3D hUC-MSC spheroids and monolayer-cultured hUC-MSCs were employed to treat a cyclophosphamide-induced POF rat model through orthotopic transplantation. The effects of these two forms on POF were subsequently assessed by examining apoptosis, autophagy, and oxidative damage in ovarian granulosa cells (GCs). The results indicated that hUC-MSC spheroids exhibited superior treatment effects on resisting autophagy, apoptosis, and oxidative damage in GCs compared to monolayer-cultured hUC-MSCs. To further elucidate the impact of hUC-MSC spheroids in vitro, a H2O2-induced KGN cells model was established and co-cultured with both forms of hUC-MSCs. As expected, the hUC-MSC spheroids also exhibited superior effects in resisting apoptosis and autophagy caused by oxidative damage. Therefore, this study demonstrates that 3D hUC-MSC spheroids have potential advantages in POF therapy; however, the detailed mechanisms need to be further investigated. Furthermore, this study will provide a reference for the clinical treatment strategy of POF.

Patients with gynecological malignancies are similar to other IVF patients without cancer for clinical and molecular reproductive parameters and DNA damage response pattern.

This study intended to investigate if gynecological cancers compromise ovarian function and reduce the success of assisted reproduction techniques (ART). No clinical and molecular data together is available on this issue for gynecological or other organ cancers. Steroidogenic pathways and DNA damage response characteristics of the granulosa cells retrieved from the 39 gynecological cancer patients were analyzed together with their clinical ART characteristics in comparison to 31 control ART patients. Patients with gynecological malignancies were similar to the control IVF patients for the number of mature oocytes retrieved, fertilization rates and embryo development competency. Molecular analyses of the granulosa cells retrieved from these cancer patients did not detect any perturbations in gonadotropin receptor expression and response, sex steroid production, cholesterol utilization/storage and, DNA damage response pattern in comparison to control IVF patients without cancer. This study provides the first reassuring clinical and molecular combined data set that the presence of gynecological malignancy does not appear to have any detrimental effect on clinical IVF cycle characteristics and ovarian functioning at molecular level.

Normal Ovarian Function in Subfertile Mouse with Amhr2-Cre-Driven Ablation of Insr and Igf1r.

Insulin receptor signaling promotes cell differentiation, proliferation, and growth which are essential for oocyte maturation, embryo implantation, endometrial decidualization, and placentation. The dysregulation of insulin signaling in women with metabolic syndromes including diabetes exhibits poor pregnancy outcomes that are poorly understood. We utilized the Cre/LoxP system to target the tissue-specific conditional ablation of insulin receptor (Insr) and insulin-like growth factor-1 receptor (Igf1r) using an anti-Mullerian hormone receptor 2 (Amhr2) Cre-driver which is active in ovarian granulosa and uterine stromal cells. Our long-term goal is to examine insulin-dependent molecular mechanisms that underlie diabetic pregnancy complications, and our conditional knockout models allow for such investigation without confounding effects of ligand identity, source and cross-reactivity, or global metabolic status within dams. Puberty occurred with normal timing in all conditional knockout models. Estrous cycles progressed normally in Insrd/d females but were briefly stalled in diestrus in Igf1rd/d and double receptor (DKO) mice. The expression of vital ovulatory genes (Lhcgr, Pgr, Ptgs2) was not significantly different in 12 h post-hCG superovulated ovaries in knockout mice. Antral follicles exhibited an elevated apoptosis of granulosa cells in Igf1rd/d and DKO mice. However, the distribution of ovarian follicle subtypes and subsequent ovulations was normal in all insulin receptor mutants compared to littermate controls. While ovulation was normal, all knockout lines were subfertile suggesting that the loss of insulin receptor signaling in the uterine stroma elicits implantation and decidualization defects responsible for subfertility in Amhr2-Cre-derived insulin receptor mutants.

Ghrelin Alleviates Inflammation, Insulin Resistance, and Reproductive Abnormalities in Mice with Polycystic Ovary Syndrome via the TLR4-NF-κB Signaling Pathway.

BACKGROUND: Polycystic ovary syndrome (PCOS) commonly impacts fertile females with potentially severe effects on fertility and metabolism. Blood ghrelin levels are lower in PCOS patients, and exogenous supplements have been proposed for their potential to trigger anti-inflammatory effects at the cellular level. This study aimed to investigate whether pretreatment with ghrelin reduced inflammation, insulin resistance, and reproductive abnormalities in PCOS and the underlying mechanism of this disorder. METHODS: Ghrelin supplementation was first tested in an inflammation model using human ovarian granulosa cells (KGN cells) that were built by treated with Lipolyaccharide. KGN cells were pretreated with ghrelin and exposed to lipopolysaccharide (LPS). Inflammatory gene expression and cytokine production were analyzed by Enzyme-linked immunosorbent assay (ELISA). Based on these results, the PCOS mice model was built with Dehydroepiandrosterone (DHEA) and a high-fat diet. The mRNA and protein expressions of inflammatory factors including Toll-like receptor 4 (TLR4), nuclear factor kappa-B-p65 (NF-κB-p65), Phospho-NF-κB-p65 (p-NF-κB-p65) and myeloid differentiation factor 88 (MYD88) related to the TLR4/NF-κB signaling pathway were evaluated in KGN cells and mouse ovarian tissues using Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR) and western blot, respectively. Lipid metabolism was quantified via an automated biochemical analyzer. RESULTS: The mRNA and protein expressions of interleukin-6 (IL-6), interleukin-1 beta (IL-1ß), and tumor necrosis factor alpha (TNF-α) in ghrelin pretreated KGN cells were lower than the LPS group (p < 0.05). Protein expression was reduced for TLR4, NF-κB-p65, and MYD88 within KGN cells of ghrelin groups compared to the LPS group (p < 0.05). Ghrelin treatment restored the estrous cycle and slowed weight gain and abdominal fat weight of PCOS mice (p < 0.05). Ghrelin treatment decreased the serum concentrations of testosterone, luteinizing hormone, insulin, IL-6, IL-1ß, and TNF-α compared to the PCOS group (p < 0.05). Estradiol concentrations of mice treated with ghrelin were higher than the PCOS group (p < 0.05). The concentrations of low and high-density lipoprotein, triglyceride, and cholesterol in mice treated with ghrelin were lower than in the PCOS mice (p < 0.05). Inflammatory gene expression for IL-6, IL-1ß, TNF-α, TLR4, NF-κB-p65, and MYD88 decreased in the ovarian tissues of ghrelin-treated mice compared to the PCOS group (p < 0.05), along with reduced protein expression of TLR4, p-NF-κB-p65, and MYD88 (p < 0.05). CONCLUSIONS: In the present study, ghrelin treatment effectively reduced inflammation in vitro, and attenuated insulin resistance and reproductive abnormalities in PCOS mice through the TLR4/NF-κB signaling pathway, highlighting potential therapeutic avenues for future PCOS treatments and research directions.

FGF2 promotes the proliferation of injured granulosa cells in premature ovarian failure via Hippo-YAP signaling pathway.

Young women undergoing anticancer treatment are at risk of premature ovarian failure (POF). Endometrial-derived stem cells (EnSCs) have demonstrated significant therapeutic potential for treating ovarian insufficiency, although the underlying mechanisms remain to be fully understood. This study aims to further investigate the therapeutic effects of EnSCs, particularly through the paracrine action of fibroblast growth factor 2 (FGF2), on POF. The findings show that exogenous FGF2 enhances the survival of ovarian granulosa cells damaged by cisplatin. FGF2 stimulates the proliferation of these damaged cells by suppressing the Hippo signaling pathway and activating YAP expression. In vivo experiments also revealed that FGF2 treatment significantly improves ovarian reserve and endocrine function in mice with POF. These results suggest that FGF2 can boost the proliferative capacity of damaged ovarian granulosa cells through the Hippo-YAP signaling pathway, providing a theoretical foundation for using EnSCs and FGF2 in clinical treatments for POF.

A novel perspective on di-hexyl phthalate (2-ethylhexyl)-induced reproductive toxicity in females: Lipopolysaccharide synergizes with mono-2-ethylhexyl ester to cause inflammatory apoptosis rather than autophagy in ovarian granulosa cells.

Di-hexyl phthalate (2-ethylhexyl) (DEHP) has been confirmed to cause female reproductive toxicity in humans and model animals by affecting the survival of ovarian granulosa cells (GCs), but the interrelationships between DEHP's on autophagy, apoptosis, and inflammation in GCs are not clear. Our previous study demonstrated that DEHP exposure resulted in the disturbance of intestinal flora associated with serum LPS release, which in turn led to impaired ovarian function. LPS has also been shown to determine cell fate by modulating cellular autophagy, apoptosis, and inflammation. Therefore, this study investigated the role and link between LPS and autophagy, apoptosis, and inflammation of GCs in DEHP-induced ovarian injury. Here, we constructed an in vivo injury model by continuous gavage of 0-1500 mg/kg of DEHP in female mice for 30 days and an in vitro injury model by treatment of human ovarian granulosa cells (KGN) cells with mono-2- ethylhexyl ester (MEHP, an active metabolite of DEHP in vivo). In addition, the expression of relevant pathway molecules was detected by immunohistochemistry, immunofluorescence, qRT-PCR, and Western blotting after the addition of the autophagy inhibitor 3-methyladenine (3-MA), the apoptosis inhibitor Z-VAD- FMK and the NF-κB inhibitor BAY11-7082. The current study found that autophagy and apoptosis were significantly activated in GCs of DEHP-induced atretic follicles in vivo and found that MEHP-induced KGN cells autophagy and apoptosis were independent and potentially cytotoxic of each other in vitro. Further studies confirmed that DEHP exposure resulted in LPS release from the intestinal tract and entering the ovary, thereby participating in DEHP-induced inflammation of GCs. In addition, we found that exogenous LPS synergized with MEHP could activate the NF-κB signaling pathway to induce inflammation and apoptosis of GCs in a relatively prolonged exposure condition. Meanwhile, inhibition of inflammatory activation could rescue apoptosis and estrogen secretion function of GCs induced by MEHP combined with LPS. These results indicated that the increased LPS influenced by DEHP might cooperate with MEHP to induce inflammatory apoptosis of GCs, an important cause of ovarian injury in mice.

Rhythm gene PER1 mediates ferroptosis and lipid metabolism through SREBF2/ALOX15 axis in polycystic ovary syndrome.

OBJECTIVE: This work aimed to investigate the role of rhythm gene PER1 in mediating granulosa cell ferroptosis and lipid metabolism of polycystic ovary syndrome (PCOS). METHODS: We injected dehydroepiandrosterone and Ferrostatin-1 (Fer-1) into mice to explore the mechanism of ferroptosis in PCOS. The effect of PER1 on ferroptosis-like changes in granulosa cells was explored by overexpression of PER1 plasmid transfection and Fer-1 treatment. RESULTS: We found that Fer-1 ameliorated the characteristic polycystic ovary morphology, suppressed ferroptosis in the PCOS mice. PER1 and ALOX15 were highly expressed in PCOS, whereas SREBF2 was lowly expressed. Overexpression of PER1 decreased granulosa cell viability and inhibited proliferation. Meanwhile, overexpression of PER1 increased lipid reactive oxygen species, 4-Hydroxynonenal (4-HNE), Malondialdehyde (MDA), total Fe, and Fe2+ levels in granulosa cells and decreased Glutathione (GSH) content. Fer-1, SREBF2 overexpression, or ALOX15 silencing treatment reversed the effects of PER1 overexpression on granulosa cells. PER1 binds to the SREBF2 promoter and represses SREBF2 transcription. SREBF2 binds to the ALOX15 promoter and represses ALOX15 transcription. Correlation analysis of clinical trials showed that PER1 was positively correlated with total cholesterol, low-density lipoprotein cholesterol, luteinizing hormone, testosterone, 4-HNE, MDA, total Fe, Fe2+, and ALOX15. In contrast, PER1 was negatively correlated with SREBF2, high-density lipoprotein cholesterol, follicle-stimulating hormone, progesterone, and GSH. CONCLUSION: This study demonstrates that the rhythm gene PER1 promotes ferroptosis and dysfunctional lipid metabolism in granulosa cells in PCOS by inhibiting SREBF2/ALOX15 signaling.

Vitamin D3 reduces the symptoms of ovarian hyperstimulation syndrome in mice and inhibits the release of granulosa cell angiogenic factor through pentraxin 3.

It has been reported that the effective inhibition of vascular endothelial growth factor (VEGF) can prevent the progression of ovarian hyperstimulation syndrome (OHSS). The present study aimed to investigate the mechanism underlying the effect of vitamin D3 (VD3) on OHSS in mouse models and granulosa cells. The effects of VD3 administration (16 and 24 IU) on ovarian permeability were determined using Evans blue. In addition, ovarian pathology, corpus luteum count, inflammatory responses, and hormone and VEGFA levels were assessed using pathological sections and ELISA. Molecular docking predicted that pentraxin 3 (PTX3) could be a potential target of VD3, and therefore, the effects of human chorionic gonadotropin (hCG) and VD3 as well as PTX3 overexpression on the production and secretion of VEGFA in granulosa cells were also investigated using western blotting and immunofluorescence. Twenty-four IU VD3 significantly reversed the increase in ovarian weight and permeability in mice with OHSS. Additionally, VD3 diminished congestion and the number of corpus luteum in the ovaries and reduced the secretion levels of inflammatory factors and those of estrogen and progesterone. Notably, VD3 downregulated VEGFA and CD31 in ovarian tissues, while the expression levels of PTX3 varied among different groups. Furthermore, VD3 restored the hCG-induced enhanced VEGFA and PTX3 expression levels in granulosa cells, whereas PTX3 overexpression abrogated the VD3-mediated inhibition of VEGFA production and secretion. The present study demonstrated that VD3 could inhibit the release of VEGFA through PTX3, thus supporting the beneficial effects of VD3 administration on ameliorating OHSS symptoms.

Cellular senescence of granulosa cells in the pathogenesis of polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age, but its pathology has not been fully characterized and the optimal treatment strategy remains unclear. Cellular senescence is a permanent state of cell-cycle arrest that can be induced by multiple stresses. Senescent cells contribute to the pathogenesis of various diseases, owing to an alteration in secretory profile, termed 'senescence-associated secretory phenotype' (SASP), including with respect to pro-inflammatory cytokines. Senolytics, a class of drugs that selectively eliminate senescent cells, are now being used clinically, and a combination of dasatinib and quercetin (DQ) has been extensively used as a senolytic. We aimed to investigate whether cellular senescence is involved in the pathology of PCOS and whether DQ treatment has beneficial effects in patients with PCOS. We obtained ovaries from patients with or without PCOS, and established a mouse model of PCOS by injecting dehydroepiandrosterone. The expression of the senescence markers p16INK4a, p21, p53, γH2AX, and senescence-associated ß-galactosidase and the SASP-related factor interleukin-6 was significantly higher in the ovaries of patients with PCOS and PCOS mice than in controls. To evaluate the effects of hyperandrogenism and DQ on cellular senescence in vitro, we stimulated cultured human granulosa cells (GCs) with testosterone and treated them with DQ. The expression of markers of senescence and a SASP-related factor was increased by testosterone, and DQ reduced this increase. DQ reduced the expression of markers of senescence and a SASP-related factor in the ovaries of PCOS mice and improved their morphology. These results indicate that cellular senescence occurs in PCOS. Hyperandrogenism causes cellular senescence in GCs in PCOS, and senolytic treatment reduces the accumulation of senescent GCs and improves ovarian morphology under hyperandrogenism. Thus, DQ might represent a novel therapy for PCOS.

Human umbilical cord mesenchymal stem cells alleviate chemotherapy-induced premature ovarian insufficiency mouse model by suppressing ferritinophagy-mediated ferroptosis in granulosa cells.

Primary ovarian insufficiency (POI) in younger women (under 40) manifests as irregular periods, high follicle-stimulating hormone (FSH), and low estradiol (E2), often triggered by chemotherapy. Though mesenchymal stem cell (MSC) therapy shows promise in treating POI, its exact mechanism remains unclear. This study reveals that human umbilical cord-derived MSCs (hUC-MSCs) can protect ovarian granulosa cells (GCs) from cyclophosphamide (CTX)-induced ferroptosis, a form of cell death driven by iron accumulation. CTX, commonly used to induce POI animal model, triggered ferroptosis in GCs, while hUC-MSCs treatment mitigated this effect, both in vivo and in vitro. Further investigations using ferroptosis and autophagy inhibitors suggest that hUC-MSCs act by suppressing ferroptosis in GCs. Interestingly, hUC-MSCs activate a protective antioxidant pathway in GCs via NRF2, a stress-response regulator. Overall, our findings suggest that hUC-MSCs improve ovarian function in CTX-induced POI by reducing ferroptosis in GCs. This study not only clarifies the mechanism behind the benefits of hUC-MSCs but also strengthens the case for their clinical use in treating POI. Additionally, it opens up a new avenue for protecting ovaries from chemotherapy-induced damage by regulating ferroptosis.

Follicular fluid-derived exosomal LncRNA LIPE-AS1 modulates steroid metabolism and survival of granulosa cells leading to oocyte maturation arrest in polycystic ovary syndrome.

OBJECTIVE: Women who are of reproductive age can suffer from polycystic ovary syndrome (PCOS), an endocrine disorder. Anovulatory infertility is mostly caused by aberrant follicular development, which is seen in PCOS patients. Due to the dysfunction of reproductive and endocrine function in PCOS patients, assisted reproduction treatment is one of the main means to obtain clinical pregnancy for PCOS patients. Long non-coding RNA (lncRNA) as a group of functional RNA molecules have been found to participate in the regulation of oocyte function, hormone metabolism, and proliferation and apoptosis of granulosa cells. In this study, we investigated the role of lncRNAs in follicular fluid-derived exosomes and the underlying mechanism of lncRNA LIPE-AS1. METHODS: We used RNA sequencing to analyze the lncRNA profiles of follicular fluid-derived exosomes in PCOS patients and controls. RT-qPCR was performed to detect the expression levels of these lncRNAs in control (n = 30) and PCOS (n = 30) FF exosome samples. Furthermore, we validated the performance of lncRNA LIPE-AS1 in oocyte maturation by in vitro maturation (IVM) experiments in mouse and steroid metabolism in granulosa cells. RESULTS: We found 501 lncRNAs were exclusively expressed in the control group and another 273 lncRNAs were found to be specifically expressed in the PCOS group. LncRNA LIPE-AS1, highly expressed in PCOS exosomes, was related to a poor oocyte maturation and embryo development in PCOS patients. Reduced number of MII oocytes were observed in the LIPE-AS1 group by in vitro maturation (IVM) experiments in mouse. LIPE-AS1 was also shown to modulate steroid metabolism and granulosa cell proliferation and apoptosis by LIPE-AS1/miR-4306/LHCGR axis. CONCLUSION: These findings suggested that the increased expression of LIPE-AS1, facilitated by follicular fluid exosomes, had a significant impact on both oocyte maturation and embryo development. We demonstrated the ceRNA mechanism involving LIPE-AS1, miR-4306, and LHCGR as a regulator of hormone production and metabolism. These findings indicate that LIPE-AS1 is essential in PCOS oocyte maturation and revealed a ceRNA network of LIPE-AS1 and provided new information on abnormal steroid metabolism and oocyte development in PCOS.

Differential expression of follicular fluid exosomal microRNA in women with diminished ovarian reserve.

PURPOSE: Decreased ovarian reserve function is mainly characterized by female endocrine disorders and fertility decline. Follicular fluid (FF) exosomal microRNAs (miRNAs) have been shown to regulate the function of granulosa cells (GCs). The present study explored differentially expressed miRNAs (DEmiRNAs) in patients with diminished ovarian reserve (DOR). METHODS: FF was collected from 12 DOR patients and 12 healthy controls. DEmiRNAs between the two groups were identified and analyzed using high-throughput sequencing technology and validated by real-time quantitative PCR (RT-qPCR). RESULTS: A total of 592 DEmiRNAs were identified using high-throughput miRNA sequencing, of which 213 were significantly upregulated and 379 were significantly downregulated. The sequencing results were further validated by RT-qPCR. These DEmiRNA target genes were mainly involved in the cancer pathway, phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway, regulation of actin cytoskeleton signaling pathway, and biological processes related to protein binding, nucleoplasm, cytoplasm, and cell membrane. CONCLUSION: FF exosomal miRNAs are significantly differentially expressed in DOR patients versus non-DOR patients, underscoring their crucial role in regulating the pathogenesis of DOR.

Mitochondrial Morphology and Function Abnormality in Ovarian Granulosa Cells of Patients with Diminished Ovarian Reserve.

In this study, we examined the changes in the mitochondrial structure and function in cumulus granulosa cells of patients with diminished ovarian reserve (DOR) to explore the causes and mechanisms of decreased mitochondrial quality. The mitochondrial ultrastructure was observed by transmission electron microscope, and the function was determined by detecting the ATP content, reactive oxygen species (ROS) levels, the number of mitochondria, and the mitochondrial membrane potential. The expression of ATP synthases in relation to mitochondrial function was analyzed. Additionally, protein immunoblotting was used to compare the expression levels of mitochondrial kinetic protein, the related channel protein in the two groups. Patients with DOR had abnormal granulosa cell morphology, increased mitochondrial abnormalities, decreased mitochondrial function, and disturbed mitochondrial dynamics. Additionally, the silent information regulator 1 (SIRT1)/phospho-AMP-activated protein kinase (P-AMPK)-peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α) pathway expression was decreased, which was speculated to be associated with the decreased mitochondrial mass in the DOR group. The mitochondrial mass was decreased in granulosa cells of patients in the DOR group. The mitochondrial dysfunction observed in granulosa cells of patients in the DOR group may be associated with dysregulation of the SIRT1/P-AMPK-PGC-1α-mitochondrial transcription factor A (TFAM) pathway.

WNT4 promotes macrophage polarization via granulosa cell M-CSF and reduces granulosa cell apoptosis in endometriosis.

BACKGROUND: WNT4 gene polymorphism are common in endometriosis and may functionally link estrogen and estrogen receptor signaling. Previous study confirmed estrogen and estrogen receptor signaling recruit macrophage to promote the pathogenesis of endometriosis. To investigate the effect of WNT4 in endometriosis involved in macrophage polarization and whether WNT4 could reduce the apoptosis of granulosa cells. METHODS: An observational study consisting of 8 cases of women with endometriosis (diagnosed by surgery and histology) and 22 mice of endometriosis animal model was conducted. Granulosa cells were isolated from 16 patients with endometriosis and co-cultured with macrophage under WNT4 treatment using TUNEL assay, quantitative reverse transcription PCR, flow cytometry and ELISA analysis. 22 mice of endometriosis animal model confirmed the WNT4 treatment effects using histology and immunohistochemistry, Western blot and flow cytometry. RESULTS: We observed that the apoptotic proportion of granulosa cells was significantly decreased and M2 macrophage was significantly increased after WNT4 treatment during the granulosa cell and macrophage co-culture system. To reveal the underlying mechanism for this, we conducted a series of experiments and found that high expression of granulosa cell M-CSF led to the M2 polarization of macrophages. The animal model also suggested that the anti-apoptotic effect of WNT4 on granulosa cells were conducted by the M2 polarized macrophage. CONCLUSIONS: WNT4 could reduce granulosa cell apoptosis and improve ovarian reserve by promoting macrophage polarization in endometriosis. M-CSF secreted by granulosa cell after WNT4 treatment was the main mediator of macrophage polarization.

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.

FABP5 inhibitor SBFI-26 regulates FOXM1 expression and Wnt signaling pathway in ovarian granulosa cell of patients with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is the most prevalent endocrinopathy among females of reproductive age. Due to its unclear etiopathogenesis, it is of vital significance to take a deeper understanding of molecular mechanisms underlying PCOS. Quantitative real-time PCR (RT-qPCR) and western blot were applied for detection of gene expression and protein expression individually. Cell Counting Kit-8 (CCK-8) and colony formation assays were used for the evaluation of cell proliferation while Caspase-3/9 activity was measured for the assessment of cell apoptosis. We found that FOXM1 was overexpressed in ovarian granulosa cell (OGC) of patients with PCOS. Functionally, upregulation of FOXM1 promotes the proliferative ability of PCOS-OGC cells. As for mechanism, FOXM1 exerts its functions in PCOS-OGC cell through activation of the Wnt signaling pathway. More importantly, a novel FABP5 inhibitor, SBFI-26, was verified to downregulate the expression of FOXM1 to impede the proliferation of PCOS-OGC cells. In addition, SBFI-26 inactivates Wnt signaling pathway in PCOS-OGC cells. FABP5 inhibitor SBFI-26 regulates FOXM1 expression and Wnt signaling pathway in OGC of patients with PCOS, which might provide a new perspective into PCOS treatment.

Serum granulosa cell-derived TNF-α promotes inflammation and apoptosis of renal tubular cells and PCOS-related kidney injury through NF-κB signaling.

Polycystic ovary syndrome (PCOS) is a disorder with endocrinal and metabolic problems in reproductive aged women. Evidence shows that PCOS is in a high prone trend to develop kidney diseases. In this study, we investigated the mediators responsible for PCOS-related kidney injury. We found that tumor necrosis factor (TNF-α) levels were significantly increased in serum and primary cultured granulosa cells (GCs) from PCOS patients. Serum TNF-α levels were positively correlated with serum testosterone and luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratio, suggesting its positive role in the severity of PCOS. Serum TNF-α levels were also positively correlated with the levels of urinary KapU, LamU, α1-MU and ß2-MU, the markers for renal tubular cell-derived proteinuria. We established a PCOS mouse model by resection of the right kidney, followed by daily administration of dihydrotestosterone (DHT, 27.5 µg, i.p.) from D7 for 90 days. We found that TNF-α levels were significantly increased in the ovary and serum of the mice, accompanied by increased renal tubular cell apoptosis, inflammation and fibrosis in kidneys. Furthermore, the receptor of TNF-α, tumor necrosis factor receptor 1 (TNFR1), was significantly upregulated in renal tubular cells. We treated human ovarian granulosa-like tumor cells (KGN) with DHT (1 µg/ml) in vitro, the conditioned medium derived from the granulosa cell culture greatly accelerated apoptotic injury in human proximal tubular epithelial cells (HKC-8), which was blocked after knockdown of TNF-α in KGN cells. Furthermore, knockdown of TNFR1 in renal tubular epithelial cells greatly ameliorated cell injury induced by granulosa cell-derived conditioned medium. These results suggest that serum TNF-α plays a key role in mediating inflammation and apoptosis in renal tubular cells associated with PCOS-related kidney injury.

Ferredoxin 1 regulates granulosa cell apoptosis and autophagy in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS), a common reproductive endocrine disorder in women of reproductive age, causes anovulatory infertility. Increased apoptosis of granulosa cells has been identified as one of the key factors contributing to abnormal follicular development. Ferredoxin 1 (FDX1) encodes a small ferredoxin that is involved in the reduction in mitochondrial cytochromes and the synthesis of various steroid hormones and has the potential to influence the function of granulosa cells. In the present study, we aimed to determine the relationship between FDX1 and follicular granulosa cell function. To this end, we investigated the difference between FDX1 expression in the granulosa cells of 50 patients with PCOS and that of the controls. Furthermore, we sought to elucidate the role and mechanism of FDX1 in PCOS granulosa cells by establishing a mouse PCOS model with dehydroepiandrosterone and KGN (a steroidogenic human granulosa cell-like tumor cell line). The results indicated significant up-regulation of FDX1 in the granulosa cells after androgen stimulation. Knockdown of FDX1 promoted the proliferation of KGN and inhibited apoptosis. Moreover, FDX1 could regulate autophagy by influencing the autophagy proteins ATG3 and ATG7. Our results demonstrated that FDX1 plays a critical role in female folliculogenesis by mediating apoptosis, autophagy, and proliferation. Therefore, FDX1 may be a potential prognostic factor for female infertility.

LncRNA NEAT1 inhibits apoptosis and autophagy of ovarian granulosa cells through miR-654/STC2-mediated MAPK signaling pathway.

Long non-coding RNA (lncRNA) anomalies cause early ovarian failure. LncRNA nuclear enriched abundant transcript 1 (NEAT1) was down-regulated in premature ovarian failure (POF) mice and connected to the illness, however, the mechanism remained unclear. The levels of gene and protein were measured by using quantitative real-time polymerase chain reaction, Western blot, and immunofluorescence. Follicle stimulating hormone (FSH), estradiol (E2), and luteinizing hormone (LH) levels were determined using enzyme-linked immunosorbent assay (ELISA). 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry were used to determine cell viability and apoptosis. The interaction of NEAT1, miR-654, and stanniocalcin-2 (STC2) was verified by dual-luciferase reporter assay or RNA binding protein immunoprecipitation (RIP) assays. The results showed NEAT1 and STC2 down-regulated, while miR-654 up-regulated in POF mice. Overexpression of NEAT1 reduced apoptosis and autophagy in cyclophosphamide (CTX)-treated ovarian granulosa cells (OGCs), and Bax, cleaved-caspase3, LC3B, LC3II/LC3I ratio were decreased and Bcl-2 and p62 were raised. NEAT1 suppressed miR-654 expression by directly targeting miR-654. The inhibition of NEAT1 overexpression on apoptosis and autophagy in OGCs was reversed by miR-654 mimics. STC2 was a target gene of miR-654, and miR-654 inhibitor reduced the apoptosis and autophagy by regulating the STC2/MAPK axis. To sum up, NEAT1 reduced miR-654 expression and modulated the STC2/MAPK pathway to decrease apoptosis and autophagy in POF, indicating a potential therapeutic target.

ROS-CCL5 axis recruits CD8+ T lymphocytes promoting the apoptosis of granulosa cells in diminished ovary reserve.

Follicular atresia was initiated with the apoptosis of granulosa cells (GCs) mostly mediated by oxidative stress (OS). Our previous studies found that the number of CD8+ T cells and proportion of CD8+/CD4+ T cells increased in the follicles of diminished ovary reserve (DOR). However, the mechanism was still poorly explored. Herein, our results showed that the level of H2O2 in follicular fluid (FF) and reactive oxygen species (ROS) in GCs were increased, while the expression of SOD1, SOD2 and GPX1 was down-regulated in GCs with DOR. In addition, we found that OS within a certain range promoted the expression of CCL5 in GCs, which facilitated the infiltration of CD8+ T cells to the follicles. In vitro co-culture experiment showed that CD8+ T cells inhibited GCs proliferation and promoted their apoptosis through intrinsic apoptosis pathway. Maraviroc, the CCR5 antagonist, alleviated CCL5-induced immune attack of CD8+ T cells. Our results indicated that ROS-CCL5 axis recruited CD8+ T cells into FF resulting in the apoptosis of GCs in DOR. This has further implications for the understanding of the pathology of DOR and searching for the therapeutic management of this disease.