Human Ovarian Granulosa Cells Research Articles

Luteolin and its analog luteolin-7-methylether from Leonurus japonicus Houtt suppress aromatase-mediated estrogen biosynthesis to alleviate polycystic ovary syndrome by the inhibition of tumor progression locus 2

Ethnopharmacological relevanceLeonurus japonicus Houtt (L. japonicus, Chinese motherwort), known as Yi Mu Cao which means “good for women”, has long been widely used in China and other Asian countries to alleviate gynecological disorders, often characterized by estrogen dysregulation. It has been used for the treatment of polycystic ovary syndrome (PCOS), a common endocrine disorder in women but the underlying mechanism remains unknown. Aim of the studyThe present study was designed to investigate the effect and mechanism of flavonoid luteolin and its analog luteolin-7-methylether contained in L. japonicus on aromatase, a rate-limiting enzyme that catalyzes the conversion of androgens to estrogens and a drug target to induce ovulation in PCOS patients. Materials and methodsEstrogen biosynthesis in human ovarian granulosa cells was examined using ELISA. Western blots were used to explore the signaling pathways in the regulation of aromatase expression. Transcriptomic analysis was conducted to elucidate the potential mechanisms of action of compounds. Finally, animal models were used to assess the therapeutic potential of these compounds in PCOS. ResultsLuteolin potently inhibited estrogen biosynthesis in human ovarian granulosa cells stimulated by follicle-stimulating hormone. This effect was achieved by decreasing cAMP response element-binding protein (CREB)-mediated expression of aromatase. Mechanistically, luteolin and luteolin-7-methylether targeted tumor progression locus 2 (TPL2) to suppress mitogen-activated protein kinase 3/6 (MKK3/6)-p38 MAPK-CREB pathway signaling. Transcriptional analysis showed that these compounds regulated the expression of different genes, with the MAPK signaling pathway being the most significantly affected. Furthermore, luteolin and luteolin-7-methylether effectively alleviated the symptoms of PCOS in mice. ConclusionsThis study demonstrates a previously unrecognized role of TPL2 in estrogen biosynthesis and suggests that luteolin and luteolin-7-methylether have potential as novel therapeutic agents for the treatment of PCOS. The results provide a foundation for further development of these compounds as effective and safe therapies for women with PCOS.

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.

House Dust-Derived Mixtures of Organophosphate Esters Alter the Phenotype, Function, Transcriptome, and Lipidome of KGN Human Ovarian Granulosa Cells.

Organophosphate esters (OPEs), used as flame retardants and plasticizers, are present ubiquitously in the environment. Previous studies suggest that exposure to OPEs is detrimental to female fertility in humans. However, no experimental information is available on the effects of OPE mixtures on ovarian granulosa cells, which play essential roles in female reproduction. We used high-content imaging to investigate the effects of environmentally relevant OPE mixtures on KGN human granulosa cell phenotypes. Perturbations to steroidogenesis were assessed using ELISA and qRT-PCR. A high-throughput transcriptomic approach, TempO-Seq™, was used to identify transcriptional changes in a targeted panel of genes. Effects on lipid homeostasis were explored using a cholesterol assay and global lipidomic profiling. OPE mixtures altered multiple phenotypic features of KGN cells, with triaryl OPEs in the mixture showing higher potencies than other mixture components. The mixtures increased basal production of steroid hormones; this was mediated by significant changes in the expression of critical transcripts involved in steroidogenesis. Further, the total-OPE mixture disrupted cholesterol homeostasis and the composition of intracellular lipid droplets. Exposure to complex mixtures of OPEs, similar to those found in house dust, may adversely affect female reproductive health by altering a multitude of phenotypic and functional endpoints in granulosa cells. This study provides novel insights into the mechanisms of actions underlying the toxicity induced by OPEs and highlights the need to examine the effects of human relevant chemical mixtures.

B(a)P induces ovarian granulosa cell apoptosis via TRAF2-NFκB-Caspase1 axis during early pregnancy

Benzo(a)pyrene [B(a)P] is an environmental endocrine disruptor with reproductive toxicity. The corpus luteum (CL) of the ovary plays an important role in embryo implantation and pregnancy maintenance. Our previous studies have shown that B(a)P exposure affects embryo implantation and endometrial decidualization in mouse, but its effects and mechanisms on CL function remain unclear. In this study, we explore the mechanism of ovarian toxicity of B(a)P using a pregnant mouse model and an in vitro model of human ovarian granulosa cells (GCs) KGN. Pregnant mice were gavaged with corn oil or 0.2 mg/kg.bw B(a)P from pregnant day 1 (D1) to D7, while KGN cells were treated with DMSO, 1.0IU/mL hCG, or 1.0IU/mL hCG plus benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), a B(a)P metabolite. Our findings revealed that B(a)P exposure damaged embryo implantation and reduced estrogen and progesterone levels in early pregnant mice. Additionally, in vitro, BPDE impaired luteinization in KGN cells. We observed that B(a)P/BPDE promoted oxidative stress (OS) and inflammation, leading to apoptosis rather than pyroptosis in ovaries and luteinized KGN cells. This apoptotic response was mediated by the activation of inflammatory Caspase1 through the cleavage of BID. Furthermore, B(a)P/BPDE inhibited TRAF2 expression and suppressed NFκB signaling pathway activation. The administration of VX-765 to inhibit the Caspase1 activation, over-expression of TRAF2 using TRAF2-pcDNA3.1 (+) plasmid, and BetA-induced activation of NFκB signaling pathway successfully alleviated BPDE-induced apoptosis and cellular dysfunction in luteinized KGN cells. These findings were further confirmed in the KGN cell treated with H2O2 and NAC. In conclusion, this study elucidated that B(a)P/BPDE induces apoptosis rather than pyroptosis in GCs via TRAF2-NFκB-Caspase1 during early pregnancy, and highlighting OS as the primary contributor to B(a)P/BPDE-induced ovarian toxicity. Our results unveil a novel role of TRAF2-NFκB-Caspase1 in B(a)P-induced apoptosis and broaden the understanding of mechanisms underlying unexplained luteal phase deficiency.

Cryptochrome 1 regulates ovarian granulosa cell senescence through NCOA4-mediated ferritinophagy

Age-associated decreases in follicle number and oocyte quality result in a decline in female fertility, which is associated with increased infertility. Granulosa cells play a major role in oocyte development and maturation both in vivo and in vitro. However, it is unclear whether a reduction in cryptochrome 1 (Cry1) expression contributes to granulosa cell senescence, and further exploration is needed to understand the underlying mechanisms. In this study, we investigated the role of Cry1, a core component of the molecular circadian clock, in the regulation of senescence in ovarian granulosa cells. Western blotting and qRT-PCR showed that Cry1 expression was downregulated in aged human ovarian granulosa cells and was correlated with age and anti-Müllerian hormone (AMH) levels. RNA-seq analysis suggested that ferritinophagy was increased after Cry1 knockdown in KGN cells. MDA, iron, and reactive oxygen species (ROS) assays were used to detect cellular ferritinophagy levels. Ferroptosis inhibitors, iron chelators, autophagy inhibitors, and nuclear receptor coactivator 4 (NCOA4) knockdown alleviated KGN cell senescence induced by Cry1 knockdown. Immunofluorescence, immunoprecipitation, and ubiquitination assays indicated that Cry1 affected NCOA4 ubiquitination and degradation through HERC2, thereby affecting NCOA4-mediated ferritinophagy and causing granulosa cell senescence. KL201, a Cry1 stabilizer, enhanced ovarian function in naturally aged mice by reducing ferritinophagy. Our study reveals the potential mechanisms of action of Cry1 during ovarian aging and provides new insights for the clinical treatment of age-related fertility decline.

Extraction and identification of exosomes from three different sources of human ovarian granulosa cells and analysis of their differential miRNA expression profiles.

As important functional cells in the ovary, ovarian granulosa cells are involved in the regulation of oocyte growth and development and play an important role in the study of female fertility preservation. Based on the importance of granulosa cell functionalism, in this study, we analyzed the exosome secretion capacity of human ovarian granulosa cells (SVOG/KGN-cell line, PGC-primary cells) and the differences in their miRNA expression. Cells were identified by hematoxylin-eosin staining (HE) and FSHR immunofluorescence staining; CCK8 and colony-forming assay were performed to compare cell proliferation capacity; exosomes were extracted and identified by ultra-high speed centrifugation, transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blot analysis (WB), and the expression profile of each cellular exosomal miRNA was analyzed by miRNA high-throughput sequencing. The proliferative abilities of the three granulosa cells differed, but all had the ability to secrete exosomes. In the exosomes of SVOG, KGN, and PGC cells, 218, 327, and 471 miRNAs were detected, respectively. When compared to the exosomal miRNAs of PGC cells, 111 miRNAs were significantly different in SVOG, and 70 miRNAs were washed two significantly different in KGN cells. These differential miRNA functions were mainly enriched in the cell cycle, cell division/differentiation, multicellular biogenesis, and protein binding. Human ovarian granulosa cells of different origins are capable of secreting exosomes, but there are still some differences in their exosomes and exosomal miRNAs, and experimental subjects should be selected rationally according to the actual situation.

Linoleic acid induces human ovarian granulosa cell inflammation and apoptosis through the ER-FOXO1-ROS-NFκB pathway

Polycystic ovary syndrome (PCOS) is a complex reproductive endocrinological disorder influenced by a combination of genetic and environmental factors. Linoleic acid (LA) is a widely consumed ω-6 polyunsaturated fatty acid, accounting for approximately 80% of daily fatty acid intake. Building upon the prior investigations of our team, which established a connection between LA levels in the follicular fluid and PCOS, this study deeply examined the specific impact of LA using a granulosa cell line. Our findings revealed that LA exerts its influence on granulosa cells (GCs) by binding to the estrogen receptor (ER). Activated ER triggers the transcription of the FOXO1 gene. Reactive oxygen species (ROS)-related oxidative stress (OS) and inflammation occur downstream of LA-induced FOXO1 activation. Increased OS and inflammation ultimately culminate in GC apoptosis. In summary, LA modulates the apoptosis and inflammation phenotypes of GCs through the ER-FOXO1-ROS-NF-κB pathway. Our study provides additional experimental evidence to comprehend the pathophysiology of PCOS and provides novel insights into the dietary management of individuals with PCOS.

Protective effect of bioactive components from Rubi fructus against oxidative damage in human ovarian granulosa cells induced by 2,2-azobis (2-methylpropionamidine) dihydrochloride.

Diminished ovarian reserve has a serious impact on female reproduction with an increasing incidence every year. An important cause of this is oxidative stress. Rubi fructus, a traditional medicinal and edible plant, has shown therapeutic effects against gynecological diseases. Vanillic acid, isoquercitrin, kaempferol-3-O-rutinoside, kaempferol-3-O-sophoroside, oleanolic acid, tormentic acid, tiliroside, and ellagic acid are the major bioactive components in R. fructus. However, studies involved in the effectiveness and mechanism of these components in oxidative stress-induced ovarian dysfunction are scarce. In this study, the protective mechanisms of the bioactive components were evaluated in human ovarian granulosa cells. Isoquercitrin was significantly superior to other bioactive components in relieving damage in human ovarian granulosa cells induced by 2,2-azobis (2-methylpropionamidine) dihydrochloride, considering enhanced cell viability, reduced reactive oxygen species accumulation, and improved mitochondrial membrane potential level. Isoquercitrin protected human ovarian granulosa cells from oxidative stress by regulating the enzyme activity of glutathione peroxidase, inhibiting cell apoptosis, improving the expression of genes related to oxidative stress, and ameliorating heme oxygenase 1 protein expression. Isoquercitrin, a bioactive component in R. fructus, has a significant protective effect on oxidative damage induced by 2,2-azobis (2-methylpropionamidine) dihydrochloride in human ovarian granulosa cells, providing evidence for its potential application in protecting ovarian function. © 2024 Society of Chemical Industry.

The mechanism of NRF2 inhibiting ROS induced autophagy to reduce ovarian granulosa cells damage

This study explores the effects and possible mechanisms of nuclear factor E2 related factor 2 (NRF2) on ovarian granulosa cells, providing a scientific basis to prevent premature ovarian failure. An ovarian cell injury model was constructed by treating human ovarian granulosa cell (KGN cell) with 4-Vinylcyclohexene dioxide (VCD). Firstly, KGN cells were treated with different concentrations of VCD, and cell counting kit 8 (CCK-8) was used to detect ovarian cell proliferation. After determining IC50 by CCK8, the levels of estradiol and progesterone in the cell supernatant were detected using enzyme-linked immunosorbent assay (ELISA), reactive oxygen species (ROS) assay kit was used to detect the content of ROS in ovarian cells, real-time fluorescence quantitative polymerase chain reaction (qRT PCR) was used to detect the mRNA expression level of NRF2, and Western blot was used to detect the protein expression level of NRF2. Further, NRF2 silence (siNRF2) and overexpression (NRF2-OE) cell models were constructed through lentivirus transfection, and the effects of regulating NRF2 on VCD treated cell models were investigated by detecting hormone levels, oxidative stress indicators (ROS, SOD, GSH-Px), and autophagy (LC3B level). The results showed that VCD intervention inhibited the proliferation of ovarian granulosa cells in a time-dependent and dose-dependent manner (F>100, P<0.05), with an IC50 of 1.2 mmol/L at 24 hours. After VCD treatment, the level of estradiol in the cell supernatant decreased from (56.32±10.18) ng/ml to (24.59±8.75) ng/ml (t=5.78, P<0.05). Progesterone decreased from (50.25±7.03) ng/ml to (25.13±6.67) ng/ml (t=6.54, P<0.05). After VCD treatment, the SOD of cells decreased from (44.47±7.71) ng/ml to (30.92±4.97) ng/ml (t=3.61, P<0.05). GSH-Px decreased from (68.51±10.17) ng/ml to (35.19±6.59) ng/ml (t=5.73, P<0.05). Simultaneously accompanied by an increase in autophagy and a decrease in NRF2. This study successfully constructed KGN cell models that silenced NRF2 and overexpressed NRF2. Subsequently, this study treated each group of cells with VCD and found that the cell proliferation activity of the siNRF2 group was significantly reduced (t=8.37, P<0.05), while NRF2-OE could reverse the cell activity damage caused by VCD (t=3.37, P<0.05). The siNRF2 group had the lowest level of estradiol (t=5.78, P<0.05), while NRF2-OE could reverse the decrease in cellular estradiol levels caused by VCD (t=5.58, P<0.05). The siNRF2 group had the lowest progesterone levels (t=3.02, P<0.05), while NRF2-OE could reverse the decrease in cellular progesterone levels caused by VCD (t=2.41, P<0.05). The ROS level in the siNRF2 group was the highest (t=2.86, P<0.05), NRF2-OE could reverse the increase in ROS caused by VCD (t=3.14, P<0.05), the SOD enzyme content in the siNRF2 group was the lowest (t=2.98, P<0.05), and NRF2-OE could reverse the decrease in SOD enzyme content caused by VCD (t=4.72, P<0.05). The GSH-Px enzyme content in the siNRF2 group was the lowest (t=3.67, P<0.05), and NRF2-OE could reverse the decrease in antioxidant enzyme content caused by VCD (t=2.71, P<0.05). The LC3B level was highest in the siNRF2 group (t=2.45, P<0.05), and NRF2-OE was able to reverse the LC3B elevation caused by VCD (t=9.64, P<0.05). In conclusion, NRF2 inhibits ROS induced autophagy, thereby playing a role in reducing ovarian granulosa cell damage, which may be a potential target for premature ovarian failure.

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

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. 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. The mRNA and protein expressions of interleukin-6 (IL-6), interleukin-1 beta (IL-1β), 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-1β, 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-1β, 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). 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.

XinJiaCongRongTuSiZiWan protects triptolide-induced rats from oxidative stress injury via mitophagy mediated PINK1/Parkin signaling pathway.

XinJiaCongRongTuSiZiWan (XJCRTSZW) is a traditional Chinese medicine compound for invigorating the kidney, nourishing blood, and promoting blood circulation. This study aimed to explore the effect of XJCRTSZW on triptolide (TP)-induced oxidative stress injury. Adult female Sprague-Dawley rats and human ovarian granulosa cell lines were treated with TP and XJCRTSZW. Hematoxylin and eosin staining, enzyme-linked immunosorbent assay, flow cytometry, CCK-8, JC-1 staining, transmission electron microscopy, reverse transcription-quantitative polymerase chain reaction, and Western blotting were performed in this study. XJCRTSZW treatment observably ameliorated the TP-induced pathological symptoms. Furthermore, XJCRTSZW treatment observably enhanced the TP-induced reduction of estradiol, anti-Mullerian hormone, progesterone, superoxide dismutase, ATP content, mitochondrial membrane potential, p62, and Hsp60mRNA, and protein levels in vivo and in vitro (p < 0.05). However,TP-induced elevation of follicle stimulating hormone and luteinizing hormone concentrations, malondialdehyde levels, reactive oxygen species levels, apoptosis rate, mitophagy, and the mRNA and protein expressions of LC3-II/LC3-I, PTEN-induced kinase 1 (PINK1), and Parkin were decreased (p < 0.05). In addition, XJCRTSZW treatment markedly increased cell viability in vitro (p < 0.05). XJCRTSZW protects TP-induced rats from oxidative stress injury via the mitophagy-mediated PINK1/Parkin pathway.

Berberine Protects Against Dihydrotestosterone-Induced Human Ovarian Granulosa Cell Injury and Ferroptosis by Regulating the Circ_0097636/MiR-186-5p/SIRT3 Pathway.

Polycystic ovarian syndrome (PCOS) is an endocrine syndrome in women of reproductive age. Berberine (BBR) is a Chinese herbal monomer that exhibits many pharmacological properties related to PCOS treatment. This study aims to analyze the effect of BBR on a cell model of PCOS and the underlying mechanism. Human ovarian granulosa (KGN) cells were treated with dihydrotestosterone (DHT) to mimic a PCOS cell model. The RNA expression of circ_0097636, miR-186-5p, and sirtuin3 (SIRT3) was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was detected by western blotting. Cell viability was analyzed by CCK-8 assay. Cell proliferation and apoptosis were investigated by 5-ethynyl-2'-deoxyuridine (EdU) assay and flow cytometry assay, respectively. The levels of interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α) were analyzed by enzyme-linked immunosorbent assays (ELISAs). Fe2+ concentration was assessed by an iron assay kit. Oxidative stress was assessed by detecting reactive oxygen species (ROS) level and malondialdehyde (MDA) level using commercial kits. The association of miR-186-5p with circ_0097636 and SIRT3 was identified by dual-luciferase reporter assay and RNA pull-down assay. Circ_0097636 expression was downregulated in the follicular fluid of PCOS patients and DHT-treated KGN cells when compared with control groups. BBR treatment partially relieved the DHT-induced inhibitory effect on cell proliferation and promoted effects on cell apoptosis, inflammation, ferroptosis, and oxidative stress in KGN cells. Additionally, circ_0097636 bound to miR-186-5p, and SIRT3 was identified as a target gene of miR-186-5p in KGN cells. BBR treatment ameliorated DHT-induced KGN cell injury by upregulating circ_0097636 and SIRT3 expression and downregulating miR-186-5p expression. Moreover, circ_0097636 overexpression protected KGN cells from DHT-induced injury by increasing SIRT3 expression. BBR ameliorated DHT-induced KGN cell injury and ferroptosis by regulating the circ_0097636/miR-186-5p/SIRT3 pathway.

Bone morphogenetic protein-9 downregulates StAR expression by inducing snail expression via SMAD1/5/8 signaling in human granulosa-lutein cells

Ovarian steroidogenesis mediated by granulosa cells is pivotal in maintaining normal female reproductive function. The steroidogenic acute regulatory protein (StAR) regulates the rate-limiting step in steroidogenesis. Bone morphogenetic protein-9 (BMP-9), also known as growth differentiation factor-2 (GDF-2), is a member of the transforming growth factor-beta (TGF-β) superfamily. BMP-9 induces epithelial-mesenchymal transition (EMT) that contributes to cancer progression. However, the function of BMP-9 in the female reproductive system remains largely unknown. It has been recently shown that BMP-9 is expressed in human follicular fluid and can downregulate StAR expression in human ovarian granulosa cells. However, the underlying molecular mechanisms warrant investigation. Our results show that treatment of primary granulosa-lutein (hGL) cells with BMP-9 downregulates StAR expression. In addition, two EMT-related transcription factors, Snail and Slug, are upregulated by the treatment of BMP-9. Using pharmacological inhibitors and a siRNA-mediated knockdown approach, we show that BMP-9 upregulates Snail and Slug expression by activating SMAD1/5/8 signaling. We also examine the effects of BMP-9 on SMAD-independent signaling pathways, including ERK1/2, p38, JNK, AKT, and CREB. However, none of them is affected by the BMP-9. Moreover, we use gain- and loss-of-function approaches to reveal that only Snail, not Slug, is required for the BMP-9-induced downregulation of StAR expression in hGL cells. This study increases the understanding of the physiology function of BMP-9 in hGL cells and provides important insights into the regulation of StAR expression.

Reduced PATL2 Impairs the Proliferation of Ovarian Granulosa Cells by Decreasing ADM2 Expression in Patients with PCOS.

It is recognized that PCOS patients are often accompanied with aberrant follicular development, which is an important factor leading to infertility in patients. However, the relevant regulatory mechanisms of abnormal follicular development are not well understood. In the present study, by collecting human ovarian granulosa cells (GCs) from PCOS patients who underwent in vitro fertilization (IVF), we found that the proliferation ability of GCs in PCOS patients was significantly reduced. Surprisingly, PATL2 and adrenomedullin 2 (ADM2) were obviously decreased in the GCs of PCOS patients. To further explore the potential roles of PATL2 and ADM2 on GC, we transfected PATL2 siRNA into KGN cells to knock down the expression of PATL2. The results showed that the growth of GCs remarkably repressed after knocking down the PATL2, and ADM2 expression was also weakened. Subsequently, to study the relationship between PATL2 and ADM2, we constructed PATL2 mutant plasmid lacking the PAT construct and transfected it into KGN cells. The cells showed the normal PATL2 expression, but attenuated ADM2 expression and impaired proliferative ability of GCs. Finally, the rat PCOS model experiments further confirmed our findings in KGN cells. In conclusion, our study suggests that PATL2 promoted the proliferation of ovarian GCs by stabilizing the expression of ADM2 through "PAT" structure, which is beneficial to follicular development, whereas, in the ovary with polycystic lesions, reduction of PATL2 could result in the decreased expression of ADM2, subsequently weakened the proliferation ability of GCs and finally led to the occurrence of aberrant follicles.

25(OH)D3 improves granulosa cell proliferation and IVF pregnancy outcomes in patients with endometriosis by increasing G2M+S phase cells

BackgroundThe 25-hydroxyvitamin D3 (25 (OH) D3) is crucial for follicular development. This study aimed to investigate the relationship between the level of 25 (OH) D3 in endometriosis patients, pregnancy outcomes of in vitro fertilization (IVF), and the underlying mechanism.MethodsThe 25 (OH) D3 levels in serum and follicular Fluid (FF) samples were detected using enzyme-linked immunosorbent assay (ELISA). Clinical features and pregnancy outcomes of endometriosis patients were also compared between the deficient group (< 20 ug/ml) and the adequate group (≥ 20 ug/ml). The effects of 25 (OH) D3 on the proliferation and cell cycle of human ovarian granulosa cells were respectively detected by CCK-8 assay and flow cytometry (FCM). The differentially expressed genes (DEGs) in granulosa cells of endometriosis and tubal infertility patients were screened from GEO database. The effects of 25 (OH) D3 on the expressions of CDKN2D, PPARA, TGFB2 and THBD were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot.ResultsThe levels of 25 (OH) D3 in serum and FF samples were decreased in endometriosis patients. The deficient group had fewer embryos that can be transferred, lower quality embryos and lower clinical pregnancy rates. Adequate 25 (OH) D3 levels in FF samples was a protective factor for live birth outcome in endometriosis patients. 25 (OH) D3 enhanced the proliferation capacity of granulosa cells (the concentration of 10 nM was the most significant) and increased the proportion of G2M + S phase cells. The expression of CDKN2D was decreased and TGFB2 and THBD were significantly upregulated.Conclusions25 (OH) D3 deficiency may be associated with poor IVF pregnancy outcomes in endometriosis patients. 25 (OH) D3 promotes ovarian granulosa cell proliferation by promoting the ability of cells to divide, and may accelerate cell cycle progression by up-regulating THBD and down-regulating CDKN2D expression.

A PILOT IN VITRO STUDY ON THE EFFECT OF BLUE HONEYSUCKLE EXTRACT ON HUMAN NON-CANCEROUS AND CANCEROUS OVARIAN CELLS

Honeysuckle (Lonicera caerulea L.) is utilized in Chinese, Japanese, and Russian folk medicines for centuries. The berries referred to as blue honeysuckle are recently gaining popularity in central and southern Europe due to remarkable therapeutic potential and widespread use as an ingredient in dietary supplements. The primary objective of this investigation was to examine the impact of blue honeysuckle extract on human ovarian cells – both non-cancerous HGL5 (immortalized human ovarian granulosa cell line) and cancerous OVCAR-3 (human ovarian carcinoma cell line). Cell viability, secretion of steroid hormones (17ß-estradiol and progesterone), human transforming growth factor-β2 (TGFβ-2) and its receptor (TGFBR2), and the level of apoptosis-inducing factor (AIF) were examined in ovarian granulosa cells HGL5, and the same parameters (excepting the steroid hormones) were assessed in ovarian epithelial cancer cells OVCAR-3. Blue honeysuckle ethanolic extract was applied to cells for 24 hours. AlamarBlueTM assay was used to assess cell viability, whereas secretion of steroid hormones was evaluated by ELISA. ELISA was also used to assess the levels of TGF-β2, its receptor TGFBR2 and AIF in HGL5 and OVCAR-3 cell lysates. Based on a range of doses ranging from 5 – 100 μg/mL, the extract from blue honeysuckle had no adverse effects on the viability of human ovarian cells. Futuremore, it did not affect their secretory activity – be it the release of steroid hormones or that of growth factor TGF-β2 and its receptor TGFBR2, nor did induce apoptosis (as revealed by the AIF). The present pilot study for the first time reports the effect of blue honeysuckle extract on ovarian cell models using both non-cancerous cells HGL5 and cancerous OVCAR-3 cells. These findings provide initial insights into the safety and potential utility of blue honeysuckle extract, warranting further investigation into its therapeutic applications. In further research, it is possible to examine a longer exposure time to see if it affects the cells.

Toxicological Mechanisms and Potencies of Organophosphate Esters in KGN Human Ovarian Granulosa Cells as Revealed by High-throughput Transcriptomics.

Despite the growing number of studies reporting potential risks associated with exposure to organophosphate esters (OPEs), their molecular mechanisms of action remain poorly defined. We used the high-throughput TempO-Seq™ platform to investigate the effects of frequently detected OPEs on the expression of ∼3000 environmentally responsive genes in KGN human ovarian granulosa cells. Cells were exposed for 48 h to one of five OPEs (0.1 to 50 μM): tris(methylphenyl) phosphate (TMPP), isopropylated triphenyl phosphate (IPPP), tert-butylphenyl diphenyl phosphate (BPDP), triphenyl phosphate (TPHP), or tris(2-butoxyethyl) phosphate (TBOEP). The sequencing data indicate that four OPEs induced transcriptional changes, whereas TBOEP had no effect within the concentration range tested. Multiple pathway databases were used to predict alterations in biological processes based on differentially expressed genes. At lower concentrations, inhibition of the cholesterol biosynthetic pathway was the predominant effect of OPEs; this was likely a consequence of intracellular cholesterol accumulation. At higher concentrations, BPDP and TPHP had distinct effects, primarily affecting pathways involved in cell cycle progression and other stress responses. Benchmark concentration (BMC) modelling revealed that BPDP had the lowest transcriptomic point of departure. However, in vitro to in vivo extrapolation modeling indicated that TMPP was bioactive at lower concentrations than the other OPEs. We conclude that these new approach methodologies provide information on the mechanism(s) underlying the effects of data-poor compounds and assist in the derivation of protective points of departure for use in chemical read-across and decision-making.

Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) alleviate excessive autophagy of ovarian granular cells through VEGFA/PI3K/AKT/mTOR pathway in premature ovarian failure rat model

BackgroundPremature ovarian failure (POF) is one of the leading causes of female infertility and is accompanied by abnormal endocrine, seriously affecting female quality of life. Previous studies have demonstrated that mesenchymal stem cells (MSCs) transplantation is a promising therapeutic strategy for POF. However, the mechanism remains obscure. This study aims to investigate the therapeutic effect of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on ovarian function in the POF rat model and explore the underlying mechanisms.MethodsThe ovarian function was evaluated by ovarian morphology, histology, estrous cycle, hormone levels (AMH, E2, FSH, and LH), and fertility ability to investigate the effect of hUC-MSCs on the POF rats model. The cytokines levels were assayed in serum using protein array to explore the mechanisms of hUC-MSCs therapy for POF. The excessive autophagy levels were evaluated using a co-culture system of 3D MSCs spheroids with human ovarian granulosa cell line (KGN) or primary ovarian granulosa cells (GCs) to understand the paracrine effect of hUC-MSCs on GCs. The related proteins expression of autophagy and PI3K/AKT/mTOR pathway was detected using Western Blotting and/or in various inhibitors supplement to further demonstrate that vascular endothelial growth factor A (VEGFA) secreted by hUC-MSCs can alleviate excessive autophagy of ovarian GCs via PI3K/AKT/mTOR signaling pathway. The ovarian culture model in vitro was applied to confirm the mechanism.ResultsThe ovarian function of POF and the excessive autophagy of ovarian GCs were restored after hUC-MSCs transplantation. The protein array result demonstrated that VEGF and PI3K/AKT might improve ovarian function. in vitro experiments demonstrated that VEGFA secreted by hUC-MSCs could decrease oxidative stress and inhibit excessive autophagy of ovarian GCs via PI3K/AKT/mTOR pathway. The ovarian culture model results confirmed this mechanism in vitro.ConclusionThe hUC-MSCs can alleviate excessive autophagy of ovarian GCs via paracrine VEGFA and regulate the PI3K/AKT/mTOR signaling pathway, thereby improving the ovarian function of POF.

Activation of the p62-Keap1-Nrf2 pathway protects against oxidative stress and excessive autophagy in ovarian granulosa cells to attenuate DEHP-induced ovarian impairment in mice

Di-(2-ethylhexyl) phthalate (DEHP) is widely used in various plastics but has been demonstrated to cause female reproductive toxicity. However, the exact mechanism underlying the ovarian damage induced by DEHP remains unclear. In this study, DEHP was administered orally to 5-week-old female mice for 30 days at doses of 0, 250, 500, and 1000 mg/kg/day. The findings demonstrated that DEHP exposure disrupted ovarian function and follicular development as well as induced oxidative stress and autophagy in ovarian granulosa cells (GCs). Further, 200 µM mono-(2-ethylhexyl) phthalate (MEHP), the primary metabolite of DEHP in vivo, induced autophagy in both human ovarian granulosa cells line (KGN) and mouse primary GCs within 24 h in vitro. However, it did not affect the p62-dependent autophagy flux. Furthermore, MEHP-induced autophagy was inhibited by the autophagy inhibitor 3-MA and exacerbated by the autophagy activator rapamycin, indicating that MEHP induces excessive autophagy in GCs. Subsequently, we found that MEHP-induced autophagic cell death was primarily attributed to oxidative damage from elevated intracellular ROS levels. Meanwhile, MEHP exposure induced nuclear translocation of erythroid-derived factor 2-related factor (Nrf2), a key regulator of antioxidant activity resulting in activating antioxidant effects. Interestingly, we also found that MEHP-induced increase in p62 competitively binds Keap1, thereby facilitating nuclear translocation of Nrf2 and establishing a positive feedback loop in antioxidant regulation. Therefore, this study demonstrated that inhibition of Nrf2 could aggravate oxidative damage and enhance excessive autophagy caused by MEHP, while activation of Nrf2 could reverse the trend. These findings have also been reinforced in studies of cultured ovaries in vitro. Our study suggests that the p62-Keap1-Nrf2 pathway may serve as a potential protective mechanism against DEHP-induced oxidative stress and excessive autophagy in mouse GCs.

Bushen Tianjing Recipe inhibits human ovarian granulosa cell line KGN apoptosis induced by miR-23a through the regulation of the sirtuin family

Ethnopharmacological relevanceBushen Tianjing Recipe (BTR) is a tonic-kidney formula of Traditional Chinese Medicine (TCM) with good therapeutic effects in clinical settings. It was mainly applied to inhibit the decrease of ovarian reserve function in patients. However, the anti-apoptosis mechanism of BTR remains unknown.Aim of the study: The formula of BTR is composed of prepared rehmannia root, debark peony root, carapax testudinis and asiatic cornelian cherry fruit. All four components contain the essences of nourishing yin and tonic-kidney. In the theory of TCM, the kidneys store the essence and are primarily responsible for reproduction and development. Hence, we speculated that BTR had some effect on women's reproductive system. In our research, rat serum contains BTR resolved into culture medium for incubation with miR-23a-induced KGN cells to test and determine our hypothesis. Materials and methodsBTR was prepared by the traditional decoction method to collect concentrated liquids for oral administration to rats (15.00 g/kg) for 14 days. The group with miR-23a-induced KGN cells was selected as the positive control, while the mimic one was the control. Pro-apoptosis and anti-apoptosis biomarkers were detected and analyzed by western blot together with upstream transcription factors and intracellular apoptotic signal pathways. ResultsThe medium- and high-concentration of BRT greatly reduced the apoptosis of miR-23a-induced KGN cells both in mitochondria and cytoplasm. It showed the up-regulation of SIRT1 and SIRT3, the down-regulation of pro-apoptosis factor Bax and apoptotic-related proteins Caspase 3, 8, 9, and the reduction of phosphorylation of ERK1/2 and NF-κB. however, there was no consistency in the group with a low concentration of BTR, compared with those of other groups. ConclusionOur research verified that BTR had a positive effect on women's reproductive system under medium or high concentration, illuminated the intrinsic mechanism at molecular levels, and convinced its potential application values in clinical settings.