Cultures Of Human Granulosa Cells Research Articles

New insights into the ovulatory process in the human ovary.

Successful ovulation is essential for natural conception and fertility. Defects in the ovulatory process are associated with various conditions of infertility or subfertility in women. However, our understanding of the intra-ovarian biochemical mechanisms underlying this process in women has lagged compared to our understanding of animal models. This has been largely due to the limited availability of human ovarian samples that can be used to examine changes across the ovulatory period and delineate the underlying cellular/molecular mechanisms in women. Despite this challenge, steady progress has been made to improve our knowledge of the ovulatory process in women by: (i) collecting granulosa cells across the IVF interval, (ii) creating a novel approach to collecting follicular cells and tissues across the periovulatory period from normally cycling women, and (iii) developing unique in vitro models to examine the LH surge or hCG administration-induced ovulatory changes in gene expression, the regulatory mechanisms underlying the ovulatory changes, and the specific functions of the ovulatory factors. The objective of this review is to summarize findings generated using in vivo and in vitro models of human ovulation, with the goal of providing new insights into the mechanisms underlying the ovulatory process in women. This review is based on the authors' own studies and a search of the relevant literature on human ovulation to date using PubMed search terms such as 'human ovulation EGF-signaling', 'human ovulation steroidogenesis', 'human ovulation transcription factor', 'human ovulation prostaglandin', 'human ovulation proteinase', 'human ovulation angiogenesis' 'human ovulation chemokine', 'human ovulatory disorder', 'human granulosa cell culture'. Our approach includes comparing the data from the authors' studies with the existing microarray or RNA-seq datasets generated using ovarian cells obtained throughout the ovulatory period from humans, monkeys, and mice. Current findings from studies using in vivo and in vitro models demonstrate that the LH surge or hCG administration increases the expression of ovulatory mediators, including EGF-like factors, steroids, transcription factors, prostaglandins, proteolytic systems, and other autocrine and paracrine factors, similar to those observed in other animal models such as rodents, ruminants, and monkeys. However, the specific ovulatory factors induced, their expression pattern, and their regulatory mechanisms vary among different species. These species-specific differences stress the necessity of utilizing human samples to delineate the mechanisms underlying the ovulatory process in women. The data from human ovulation in vivo and in vitro models have begun to fill the gaps in our understanding of the ovulatory process in women. Further efforts are needed to discover novel ovulatory factors. One approach to address these gaps is to improve existing in vitro models to more closely mimic in vivo ovulatory conditions in humans. This is critically important as the knowledge obtained from these human studies can be translated directly to aid in the diagnosis of ovulation-associated pathological conditions, for the development of more effective treatment to help women with anovulatory infertility or, conversely, to better manage ovulation for contraceptive purposes. N/A.

Stimulatory effects of vasopressin on progesterone production and BMP signaling by ovarian granulosa cells

The aim of the present study was to clarify the effects of arginine vasopressin (AVP) on ovarian steroid production and its functional relationship to the ovarian bone morphogenetic protein (BMP) system. The results showed that AVP treatment significantly increased gonadotropin- and forskolin-induced progesterone synthesis by primary culture of rat granulosa cells and human granulosa cells, respectively. In contrast, estradiol production was not significantly affected by AVP. Treatment with AVP significantly increased forskolin-induced cAMP synthesis by human granulosa cells and mRNA levels of the progesterogenic enzymes CYP11A1 and HSD3B2 in the cells. On the other hand, AVP also enhanced BMP-15-induced phosphorylation of SMAD1/5/9 and ID1 transcription. It was further revealed that the expression levels of BMP receptors, including ALK3, ALK6 and BMPR2, were upregulated by AVP. Collectively, the results indicate that AVP stimulates progesterone production via the cAMP-PKA pathway with upregulation of BMP signaling that inhibits progesterone production, which may lead to fine adjustment of progesterone biosynthesis by granulosa cells.

A Novel Three-Dimensional Follicle Culture System Decreases Oxidative Stress and Promotes the Prolonged Culture of Human Granulosa Cells.

Tissue engineering advancements have made it possible to modify biomaterials to reconstruct a similar three-dimensional structure of the extracellular matrix (ECM) for follicle development and to supply the required biological signals. We postulated that an artificial polysaccharide hydrogel modified with an ECM mimetic peptide may produce efficient irritation signals by binding to specific integrins providing a suitable environment for follicular development and influencing the behavior of human granulosa cells (hGCs). Laminin, an important component of the extracellular matrix, can modulate hGCs and oocyte growth. Specifically, follicles of mice were randomly divided into two-dimensional (2D) and three-dimensional (3D) culture systems established by a hydrogel modified with RGD or laminin mimetic peptides (IKVAV and YIGSR) and RGD (IYR). Our results showed that 3D cultured systems significantly improved follicle survival, growth, and viability. IYR peptides enhanced the oocyte meiosis competence. Additionally, we explored the effect of 3D culture on hGCs, which improved hGCs viability, increased the proportion of S- and G2/M-phase cells, and inhibited cell apoptosis of hGCs. On days 1 and 2, the secretion of progesterone was reduced in 3D-cultured hGCs. Notably, 3D-cultured hGCs exhibited delayed senescence, decreased oxidative stress, and elevated mitochondrial membrane potential. Moreover, the expression levels of cumulus expansion-related genes (COX2, HAS2, and PTX3) and integrin α6β1 were upregulated in 3D-cultured hGCs. In conclusion, a 3D culture utilizing hydrogels modified with Laminin-mimetic peptides can provide a durable physical environment suitable for follicular development. The laminin-mimetic peptides may regulate the biological activity of hGCs by attaching to the integrin α6β1.

DEHP Decreases Steroidogenesis through the cAMP and ERK1/2 Signaling Pathways in FSH-Stimulated Human Granulosa Cells.

DEHP is an endocrine disruptor that interferes with the function of the female reproductive system. Several studies suggested that DEHP affects steroidogenesis in human and rodent granulosa cells (GC). Some studies have shown that DEHP can also affect the FSH-stimulated steroidogenesis in GC; however, the mechanism by which DEHP affects hormone-challenged steroidogenesis in human GC is not understood. Here, we analyzed the mechanism by which DEHP affects steroidogenesis in the primary culture of human cumulus granulosa cells (hCGC) stimulated with FSH. Cells were exposed to DEHP and FSH for 48 h, and steroidogenesis and the activation of cAMP and ERK1/2 were analyzed. The results show that DEHP decreases FSH-stimulated STAR and CYP19A1 expression, which is accompanied by a decrease in progesterone and estradiol production. DEHP lowers cAMP production and CREB phosphorylation in FSH but not cholera toxin- and forskolin-challenged hCGC. DEHP was not able to decrease steroidogenesis in cholera toxin- and forskolin-stimulated hCGC. Furthermore, DEHP decreases FSH-induced ERK1/2 phosphorylation. The addition of EGF rescued ERK1/2 phosphorylation in FSH- and DEHP-treated hCGC and prevented a decrease in steroidogenesis in the FSH- and DEHP-treated hCGC. These results suggest that DEHP inhibits the cAMP and ERK1/2 signaling pathways, leading to the inhibition of steroidogenesis in the FSH-stimulated hCGC.

The effects of irisin and leptin on steroidogenic enzyme gene expression in human granulosa cells: In vitro studies

Reproduction and energy metabolism are closely related, and fertility can be directly affected by either obesity or malnutrition. In this study, we investigated the in vitro effects of irisin and leptin, two hormones primarily involved in energy metabolism, on the expression of genes encoding key steroidogenic enzymes in primary cultures of human granulosa cells. Granulosa cells were purified from follicular fluid samples obtained during in vitro fertilization (IVF) procedure, cultured, and treated with irisin (125-2000 ng/ml) or leptin (25–400 ng/ml) for 1–3 days. mRNA expression levels of cytochrome P450 enzymes [CYP11A1, CYP19A1, CYP21A2], hydroxy-delta-5-steroid dehydrogenase, 3 beta and steroid delta-isomerase 1 (HSD3B1), and hydroxysteroid 17-beta dehydrogenase 3 (HSD17B3) were measured using qRT-PCR analysis. Irisin significantly upregulated CYP19A1 mRNA levels, while leptin upregulated CYP19A1 and HSD3B1 mRNA levels. These preliminary results show that irisin and leptin may directly affect the expression of the genes important for ovarian steroidogenesis and female reproduction.

AREG upregulates secreted protein acidic and rich in cysteine expression in human granulosa cells

The secreted protein acidic and rich in cysteine (SPARC) is a secreted glycoprotein and the expression of ovarian SPARC peaks during ovulation and luteinization. Besides, SPARC expression was induced by human chorionic gonadotropin (hCG) in rat granulosa cells. Amphiregulin (AREG) is the most abundant epidermal growth factor receptor (EGFR) ligand expressed in human granulosa cells and follicular fluid. AREG mediates the physiological functions of luteinizing hormone (LH)/hCG in the ovary. However, to date, the biological function of SPARC in the human ovary remains undetermined, and whether AREG regulates SPARC expression in human granulosa cells is unknown. In this study, we show that AREG upregulated SPARC expression via EGFR in a human granulosa-like tumor cell line, KGN. Treatment of AREG activated ERK1/2, JNK, p38 MAPK, and PI3K/AKT signaling pathways and all of them were required for the AREG-induced SPARC expression. Using RNA-sequencing, we identified that steroidogenic acute regulatory protein (StAR) was a downstream target gene of SPARC. In addition, we demonstrated that SPARC mRNA levels were positively correlated with the levels of StAR mRNA in the primary culture of human granulosa cells. Moreover, SPARC protein levels were positively correlated with progesterone levels in follicular fluid of in vitro fertilization patients. This study provides the regulatory role of AREG on the expression of SPARC and reveals the novel function of SPARC in progesterone production in granulosa cells.

Oxidative stress and metformin: An in-vitro study on serum and primary human granulosa cell cultures

Objective: To observe the effect of metformin on the oxidative stress (OS) levels and SIRT1 expression in primary human granulosa cell cultures from infertile females. Methods: This cross-sectional study was conducted from August 2017-July 2019 on ten infertile patients. After written informed consent, the follicular fluid of these subjects was collected for establishing primary human granulosa cell cultures (HGCs), to test the capacity of metformin to reduce OS. The cultured HGCs were divided into (i) control: HGCs without any treatment, (ii) test1: HGCs induced with H2O2 (metformin absent), and (iii) test2: HGCs treated with metformin after H2O2 induction. Baseline OS (control group) was estimated, it was induced and measured by an increase in optical density (OD) (test1 & test 2). Finally, test2 was incubated with metformin (1 ml of 100 mmol/l concentration) and it effect on the levels of OS were determined by Mishra OS assay. Effect of metformin modulating SIRT1 expression in OS-induced cells was analyzed using quantitative-PCR. Results: Age of female subjects was 32.04±2.29years and BMI was 27.61±2.15 kg/m2. Test (OS induced) samples gave an OD of 0.28 (0.16-0.40) while control HGC samples gave an OD; 0.153 (0.09-0.23). Test cells showed significant reduction in ODs after metformin treatment. The relative expression of SIRT1 in metformin untreated and treated cells was found to be 61.5% and 80%, respectively. Conclusion: Metformin was found to suppress OS in HGCs and increases the expression of SIRT1 in OS induced environment of primary cell cultures, suggesting a relationship between metformin, SIRT1 expression, and reduction of OS.

PRIMARY INFERTILITY, OXIDATIVE STRESS AND METFORMIN; IMPACT ON PRIMARY HUMAN GRANULOSA CELL CULTURES

OBJECTIVE: To observe the effect of metformin on oxidative stress (OS) levels and SIRT1 expression in primary human granulosa cell cultures from infertile females. METHODS: This cross-sectional study was conducted from August 2017–July 2019 on ten infertile patients after approval from Ethical Review Committee. After written informed consent, follicular fluid of subjects was collected for establishing primary human granulosa cell cultures (HGCs), which were used for testing capacity of metformin to reduce OS in H2O2 induced HGCs. Cultured HGCs were divided into three groups: a) Control=HGCs without any treatment, b) Test-1=HGCs induced with H2O2 (metformin absent), and c) Test-2=HGCs treated with metformin after H2O2 induction. Baseline-OS (control-group) was estimated, it was induced and measured by an increase in optical density (OD) (Test 1&2). Finally, Test-2 was incubated with metformin (1ml of 100mmol/l concentration) and effect of metformin on oxidative stress levels were determined by Mishra oxidative stress assay. Furthermore, effect of metformin to modulate SIRT1 expression in OS-induced cells was analyzed using quantitative-PCR. RESULTS: Mean age and BMI of subjects was 32.04±2.29 years and 27.61±2.15 kg/m2 respectively. Test (OS-induced) samples gave an OD of 0.28 (0.16-0.40) while control HGC samples gave an OD of 0.153 (0.09-0.23). Significant reduction was noted in ODs of metformin treated test cells. Relative expression of SIRT1 in metformin untreated and treated cells was 61.5% and 80%, respectively. CONCLUSION: Metformin was found to suppress oxidative stress in human granulosa cells and increases the expression of SIRT1 in OS induced environment of primary cell cultures.

O-192 Modulating hypoxia and oxidative stress in human ovarian tissue xenografts using adipose tissue-derived stem cells

Abstract Study question To investigate whether adipose tissue-derived stem cells (ASCs) modulate hypoxia and oxidative stress in human ovarian tissue transplants to reduce early follicle loss. Summary answer ASCs protect the follicle pool by mitigating the hypoxia-related response through HIF1↑ signaling in human xenografts and enhancing revascularization by ensuring faster tissue reperfusion. What is known already ASCs are known for their angiogenic potential and capacity to boost angiogenesis by secreting growth factors and differentiating into vessels in numerous models of wound healing in regenerative medicine. In a 2-step ovarian tissue xenotransplantation involving grafting inside a fibrin scaffold two weeks prior to transplantation, ASCs reduced follicle loss after short- and long-term grafting, as well as abnormal follicle activation, by increasing reoxygenation and revascularization in human xenografts. Study design, size, duration Prospective experimental study. Cryopreserved ovarian cortex from five adult women was transplanted to 30 nude mice, with or without ASCs (ASC group; OT group). Ovarian grafts were retrieved on days 3 (n = 5), 10 (n = 5) and 21 (n = 5). One piece of ovarian tissue per patient was fixed for analysis after thawing to serve as non-grafted controls. Participants/materials, setting, methods The 10 animals grafted for 21 days underwent in vivo microdialysis evaluation to investigate direct reactive oxygen species (ROS) kinetics. Analyses of ovarian grafts at all time points and non-grafted controls included immunolabeling for double CD34 (revascularization by host and graft components), immunofluorescence for HIF1α (hypoxia-related response), Nrf2 (oxidative stress-related response) and 8OHdG (oxidative stress-related DNA damage), and gene expression (RT-qPCR) for VEGF-A (neoangiogenesis), SOD2 (antioxidant activity) and Nrf1 (mitochondrial biogenesis). Main results and the role of chance ROS peaked sooner in the ASC group (day 2, p < 0.0001) than the OT group (day 10, p = 0.01) after grafting, indicating earlier tissue reperfusion. Total vascularization was stable in the ASC group at all time points, but lower in the OT group 3 days after grafting (p = 0.01) due to a drop in both host and graft vascular components. HIF1α expression, detected mainly in follicles, was significantly lower in primordial follicles in the ASC group than the OT group on days 3 (p = 0.008) and 10 (p = 0.01). VEGF gene expression rose significantly (around 40x) in both groups on day 3 and persisted significantly longer in the ASC group (10 days) than the OT group (3 days) (p = 0.04), emphasizing the role of ASCs as enhancers of proangiogenic factors. There was no upturn in the oxidative stress-related response (Nrf2 pathway) nor DNA damage (8OHdG) to follicles in any of the grafted groups over time, while a modest increase in both markers was observed only in the stroma after 21 days. Neither was there any major increase in SOD2 and Nrf1 gene expression, suggesting no significant activation of the Nrf2 pathway for cytoprotection from oxidative stress. Limitations, reasons for caution Although Nrf2 signaling activation was detected in human granulosa cell cultures in increasing ROS concentrations, our findings did not confirm its role in tissue damage modulation after ovarian tissue transplantation. Further studies may evidence the involvement of other pathways that modulate oxidative stress after transplantation. Wider implications of the findings The role of ASCs in protecting the follicle pool appears to be related to a decrease in hypoxia and faster ovarian graft revascularization and reperfusion, sustained by an increase in VEGF for a longer period after grafting. There was no evidence of oxidative stress-related damage, irrespective of the transplantation strategy. Trial registration number

P–229 Oxidative stress and Metformin; an in-vitro study on serum and primary human granulosa cell cultures

Abstract Study question What is the effect of administration of Metformin on the oxidative stress (OS) levels in serum and primary human granulosa cell cultures of infertile females? Summary answer Metformin suppresses oxidative stress in serum and human granulosa cells and increases the expression of SIRT1 in OS induced environment. What is known already Oxidative stress (OS) is a resultant of mitochondrial dysfunction when it either fails to fight against the oxidants or the expression of the antioxidants is not sufficient. Cellular damage including DNA damage is a common resultant of oxidative stress. OS effects the oocyte maturation and moreover, the cleavage phase in the early embryonic stage. The raised levels of OS makers are hypothesized to compromise the nuclear maturation and the mitotic spindles of the maturing oocytes. Metformin seemed to decrease oxidative stress and improve insulin resistance, dyslipidaemia and endothelial dysfunction in PCOS patients Study design, size, duration This cross-sectional study was conducted from August 2017 – July 2019, at Aga Khan Hospital in collaboration with Australian Concept Infertility Medical Centre (ACIMC) on ten infertile patients undergoing egg retrieval after ethical approval from of Aga Khan Hospital (AKU-ERC–2018–0557–601). Participants/materials, setting, methods Serum samples were obtained and analysed. Follicular fluid of these subjects was collected for establishment of primary cell culture model of normal human granulosa cells (hGCs). Serum and hGC cultures were grouped as; a) control: treatment, b) Test1: H2O2 induced OS, and c) Test2: H2O2 induced OS treated with metformin. OS was estimated in all groups by Mishra method. The two Test groups were assessed for SIRT1 levels using quantitative PCR employing SIRT1 specific primers Main results and the role of chance With mean age of 32.04 ± 2.29 years the mean BMI was 27.61 ± 2.15 kg/m2. OS was induced and measured by an increase in optical density (OD) in hGC Test samples which showed 0.28 (0.16–0.40) OD when compared with control hGC samples 0.153 (0.09–0.23). There was a significant reduction in ODs after metformin treatment in the stress induced cells 0.182 (0.05–0.30). A similar pattern was observed in the serum samples in ODs; control: 0.105 (0.09–0.15), stress induced samples: 0.199 (0.19–0.20). and stress induced serum sample with metformin treatment: 0.1415 (0.06–0.18). The Ct values obtained to express the effect of metformin on SIRT1 levels, for OS induced (Test1) and OS induced metformin treated (Test2) cells were found to be 29.12 and 26.42, respectively. We also observed a significant (85%) difference in the fold change of SIRT1 expression between metformin treated and untreated cells. Limitations, reasons for caution Small sample size is the limitation of this study. The impact of metformin on cell cultures due to different causes of infertility could not be ascertained Wider implications of the findings: Metformin suppresses oxidative stress in serum and human granulosa cells and increases the expression of SIRT1 in OS induced environment, therefore, metformin may be considered as a treatment of oxidative stress in infertile patients. Randomized control trial with large sample size is recommended to confirm the cause and effect relationship. Trial registration number Not applicable

Estradiol Regulates mRNA Levels of Estrogen Receptor Beta 4 and Beta 5 Isoforms and Modulates Human Granulosa Cell Apoptosis.

Estrogen receptor beta (ERβ) plays a critical role in granulosa cell (GC) functions. The existence of four human ERβ splice isoforms in the ovary suggests their differential implication in 17β-estradiol (E2) actions on GC apoptosis causing follicular atresia. In this study, we investigated whether E2 can regulate ERβ isoforms expression to fine tune its apoptotic activities in human GC. For this purpose, we measured by RT-qPCR the expression of ERβ isoforms in primary culture of human granulosa cells (hGCs) collected from patients undergoing in vitro fertilization, before and after E2 exposure. Besides, we assessed the potential role of ERβ isoforms on cell growth and apoptosis after their overexpression in a human GC line (HGrC1 cells). We confirmed that ERβ1, ERβ2, ERβ4, and ERβ5 isoform mRNAs were predominant over that of ERα in hGCs, and found that E2 selectively regulates mRNA levels of ERβ4 and ERβ5 isoforms in these cells. In addition, we demonstrated that overexpression of ERβ1 and ERβ4 in HGrC1 cells increased cell apoptosis by 225% while ERβ5 or ERβ2 had no effect. Altogether, our study revealed that E2 may influence GC fate by specifically regulating the relative abundance of ERβ isoforms mRNA to modulate the balance between pro-apoptotic and non-apoptotic ERβ isoforms.

Histone demethylases JHDM1D, PHF2 and PHF8 expression pattern in granulosa cells obtained from patients undergoing IVF procedure during short-term IVC

Abstract Granulosa cells play an important role in follicle development, maturation, and atresia. They are a cellular source of the two most important ovarian steroids, namely, estradiol and progesterone and are also crucial for bidirectional communication with the oocyte, thus being involved in the regulation of its growth, development and function. Growing body of evidence suggests that granulosa cells cultured in vitro display stemness and transdifferentiation potential. Together with the fact that they can be easily collected during IVF procedures, these properties of GCs may be of particular interest for both regenerative medicine and transplantology. Establishment of in vitro cell culture and its thorough characterization, including molecular, is crucial for future potential utilization of human granulosa cells in design of engineered tissue grafts or cell-based therapies, in particular targeted at female infertility. Nevertheless, the transcriptomic alterations which may occur during in vitro culture of granulosa cells are still largely uncharacterized. The aim of this study was to examine expression changes of three genes encoding histone demethylases which serve as transcription coactivators in short term in vitro cell culture of human granulosa cells. The study groups consisted of 14 patients, aged 18–40 years undergoing in vitro fertilization (IVF). Expression level assessment was performed after 24 h, 48 h, 72 h, 96 h, 120 h, 144 h and 168 h of in vitro primary cell culture utilizing RT-qPCR technique. Upregulation of PHF2 expression in all time points of the culture was observed, whereas the tendency of JHDM1D and PHF8 was mainly to decrease in expression level. Further study on a larger population would be required in order to confirm the presented tendencies. Running title: Expression pattern of selected histone demethylases in human granulosa cells

Different expression and localization of aquaporin 7 and aquaporin 9 in granulosa cells, oocytes, and embryos of patients with polycystic ovary syndrome and the negatively correlated relationship with insulin regulation

To investigate the expression of aquaporin 7 (AQP7) and aquaporin 9 (AQP9) in the granulosa cells of patients with polycystic ovary syndrome (PCOS) and healthy women and detect their localization in oocytes at the germinal vesicle (GV), metaphase I (MI), MII, embryo, and blastocyst stages and the invitro response to insulin stimulation. Randomized, assessor-blinded study. Reproductive medical center. A total of 40 women (aged 20-38 years) comprising 29 cases of primary infertility and 11 cases of secondary infertility, of whom 17 had an initial diagnosis of PCOS and three received a PCOS diagnosis after an infertility examination. Controlling different concentrations of insulin and different treatment times in cultures of normal human granulosa cells invitro. Expression of AQP7 and AQP9 genes and proteins in granulosa cells detected by real-time quantitative polymerase chain reaction, and localization in oocytes at the GV, MI, MII, embryo, and blastocyst stages by Western blot, immunohistochemical, and immunofluorescence assays, and concentrations of insulin in follicular fluid by enzyme-linked immunosorbent assay. The expression levels of the AQP7 mRNA and protein in the granulosa cells of patients with PCOS were higher than found in healthy controls. We found AQP7 protein expressed in human oocytes at GV, MI, MII, embryo, and blastocyst stages; it was mainly located in the nucleoplasm. In the PCOS group, the expression level of AQP9 mRNA and protein in granulosa cells was lower, and AQP9 protein was expressed in oocytes at the GV, MI, MII, embryo, and blastocyst stages; it was localized on the nuclear membrane. Compared with healthy women, the insulin expression in patients with PCOS was higher. In cultures of normal human granulosa cells invitro, the expression of AQP7 and AQP9 mRNA and protein decreased with the increase in insulin concentration; expression statistically significantly decreased when the insulin concentration was 100 nmol/L, and after 6 to 24 hours of exposure the lowest expression levels were found at 12 hours. The different localization and expression of AQP7 and AQP9 between the two groups suggests that they might be involved in oocyte maturation and embryonic development through different regulatory pathways. The expression levels of AQP7 and AQP9 were negatively correlated with insulin regulation, suggesting that insulin might affect the maturation of PCOS follicles by changing AQP7 and AQP9 expression.

Apoptosis-related genes expression in primary in vitro culture of human ovarian granulosa cells

Abstract Ovarian granulosa cells (GCs) play a crucial role in oocyte maturation, creating a favorable microenvironment around the oocyte. Therefore, enhanced apoptosis and GCs loss may negatively affect the intra-follicular milieu and compromise the oocyte quality, reducing pregnancy chances. Based on the RT-qPCR method, the present research revealed the differential expression of apoptosis-related genes (BCL2, BAX, p53, CASP9) during the seven days of primary in vitro culture of GCs isolated from patients undergoing in vitro fertilization (IVF) procedure. Individual gene expression changes may reflect the GCs survival and/or apoptotic status at different time points. Running title: Apoptosis-related genes expression in granulosa cells in vitro

The extracellular reactive oxygen species levels in primary in vitro culture of human ovarian granulosa and cumulus cells

Abstract In the female reproductive tract, reactive oxygen species (ROS) may exert physiological and pathophysio-logical effects. Although ROS play an essential role as the signaling molecules, their excessive accumulation contributes to the pathogenesis of many reproductive processes. In the ovarian follicle, ROS affect multiple physiological processes, including oocyte maturation and fertilization. However, a lack of studies showing to which extend ovarian granulosa and cumulus cells can contribute to the development of oxidative stress within the ovarian follicle. In the presented research, the extracellular ROS accumulation level was investigated using GCs and CCs primary in vitro cultures. The obtained results demonstrated a steady decrease in extracellular ROS level during GCs primary culture. By contrast, ROS concentration in CCs conditioned medium increased gradually between the first and the seventh days of culture. The observed changes may reflect the proliferation status and metabolic activity of GCs and CCs during in vitro culture. Additionally, the elevated ROS level at respective points of time could occur as a consequence of culture in atmospheric oxygen. The distinct function and localization within the ovarian follicle may explain the differences between GCs and CCs oxygen metabolism. Running title: Reactive oxygen species in primary culture of human follicular cells

Paraben concentrations found in human body fluids do not exert steroidogenic effects in human granulosa primary cell cultures

In cosmetics and food products, parabens are widely used as antimicrobial agents. Reports have suggested that parabens may be linked to infertility, owing to their effects on basal steroidogenesis properties or their capacity to inflict mitochondrial damage. Despite growing concerns about parabens as endocrine disruptors, it is unclear whether they affect any of these actions in humans, particularly at environmentally relevant concentrations. In this work, an in vitro primary culture of human granulosa cells was used to evaluate steroidogenesis, based on the assessment of progesterone production and regulation of critical steroidogenic genes: CYP11A1, HSD3B1, CYP19A1, and HSD17B1. The effects of two commercially relevant parabens, methylparaben (MPB) and butylparaben (BPB), were screened. Cells were exposed to multiple concentrations ranging from relatively low (typical environmental exposure) to relatively high. The effect was assessed by the parabens’ ability to modify steroidogenic genes, progesterone or estradiol production, and on mitochondrial health, by evaluating mitochondrial activity as well as mtDNA content. Neither MPB nor BPB showed any effect over progesterone production or the expression of genes controlling steroid production. Only BPB affected the mitochondria, decreasing mtDNA content at supraphysiological concentrations (1000 nM). Prolonged exposure to these compounds produced no effects in neither of these parameters. In conclusion, neither MPB nor BPB significantly affected basal steroidogenesis in granulosa cells. Although evidence supporting paraben toxicity is prevalent, here we put forth evidence that suggests that parabens do not affect basal steroidogenesis in human granulosa cells.

Target prediction and validation of microRNAs expressed from FSHR and aromatase genes in human ovarian granulosa cells

MicroRNAs (miRNAs) are known post-transcriptional regulators of various biological processes including ovarian follicle development. We have previously identified miRNAs from human pre-ovulatory ovarian granulosa cells that are expressed from the intronic regions of two key genes in normal follicular development: FSH receptor (FSHR) and CYP19A1, the latter encoding the aromatase enzyme. The present study aims to identify the target genes regulated by these miRNAs: hsa-miR-548ba and hsa-miR-7973, respectively. The miRNAs of interest were transfected into KGN cell line and the gene expression changes were analyzed by Affymetrix microarray. Potential miRNA-regulated genes were further filtered by bioinformatic target prediction algorithms and validated for direct miRNA:mRNA binding by luciferase reporter assay. LIFR, PTEN, NEO1 and SP110 were confirmed as targets for hsa-miR-548ba. Hsa-miR-7973 target genes ADAM19, PXDN and FMNL3 also passed all verification steps. Additionally, the expression pattern of the miRNAs was studied in human primary cumulus granulosa cell culture in relation to the expression of their host genes and FSH stimulation. Based on our findings we propose the involvement of hsa-miR-548ba in the regulation of follicle growth and activation via LIFR and PTEN. Hsa-miR-7973 may be implicated in the modulation of extracellular matrix and cell-cell interactions by regulating the expression of its identified targets.

POLYPHENOL-RICH POMEGRANATE EXTRACT AS A POTENTIAL MODULATOR OF STEROIDOGENESIS IN HUMAN OVARIAN CELLS

Pomegranate represents a rich source of phytocompounds with high medicinal value. Nowadays, many studies have shown that the pomegranate extract also possesses anti-oxidant, anti-inflammatory and anti-proliferative effects on cancer cells, thus leading to increased popularity as a functional food and nutraceuticals. The aim of the study was to determine the biological effect of dry pomegranate extract (at concentrations 5, 10, 20 and 40 µg/ml; for 24h) on the viability of ovarian cells and the secretion of steroid hormones. Cultures of human ovarian granulosa cells (HGL5) and human ovarian carcinoma cells (OVCAR-3) were used such as a model cell system. The metabolic activity was evaluated by AlamarBlueTM assay, the release of steroid hormones was assayed by the ELISA method. Experimental results indicated a significant (P≤0.001) increase of proliferation in HGL5 cells after the addition of the extract at the concentrations 5, 10 and 20 µg/ml. Moreover, the number of viable OVCAR-3 cells significantly (P≤0.05; P≤0.01; P≤0.001) decreased after the addition of the extract at the concentrations 10, 20 and 40 µg/ml compared to the control. In addition, the secretion of 17ß-estradiol by the HGL5 cells was significantly (P≤0.05; P≤0.001) increased at all used concentrations of the extract. Despite to increasing of the 17ß-estradiol secretion, progesterone levels produced by the HGL5 cells were not significantly (P≥0.05) affected at all used concentrations of the extract. The current study provided experimental evidence that the pomegranate extract might be a promising candidate as a potential modulator of steroidogenesis and as a potential chemoprotective agent.

Gene expression profiles of human granulosa cells treated with bioequivalent doses of corifollitropin alfa (CFA) or recombinant human follicle-stimulating hormone (recFSH)

Using recombinant DNA technologies, a chimeric gene containing the coding sequences of follicle stimulating hormone (FSH) β-subunit and C-terminal peptide of the human chorionic gonadotrophin (hCG) β-subunit have been designed to generate a new gonadotrophin named corifollitropin alfa (CFA). CFA has longer elimination half-life and slower rate of absorption compared with FSH, which makes CFA a long-acting hormone employed as a substitute of the recombinant FSH (recFSH) in the controlled ovarian stimulation (COS). The purpose of this study is to compare the gene expression profiles elicited by bioequivalent doses of CFA or recFSH in primary cultures of human granulosa cells (hGCs). Gonadotrophins exert their functions by binding FSH receptors (FSHRs), activating signaling pathways that increase the cyclic adenosine monophosphate (cAMP) intracellular content. Bioequivalence has been defined as the dose/duration of gonadotrophin treatment able to promote the same amount of intracellular cAMP. hGCs were treated with different doses of either gonadotrophin and the cAMP was measured after different incubation times to establish the bioequivalence. Results obtained by comparing the bioequivalent treatments, showed that CFA is more effective than recFSH in inducing aromatase gene expression after 6 and 24 h from the initial stimulation in agreement with its long-acting characteristic.

Necroptosis in primate luteolysis: a role for ceramide

The corpus luteum (CL) is a transient endocrine organ, yet molecular mechanisms resulting in its demise are not well known. The presence of phosphorylated mixed lineage kinase domain-like pseudokinase pMLKL(T357/S358) in human and nonhuman primate CL samples (Macaca mulatta and Callithrix jacchus) implied that necroptosis of luteal cells may be involved. In M. mulatta CL, pMLKL positive staining became detectable only from the mid-late luteal phase onwards, pointing to necroptosis during regression of the CL. Cell death, including necroptosis, was previously observed in cultures of human luteal granulosa cells (GCs), an apt model for the study of the human CL. To explore mechanisms of necroptotic cell death in GCs during culture, we performed a proteomic analysis. The levels of 50 proteins were significantly altered after 5 days of culture. Interconnectivity analysis and immunocytochemistry implicated specifically the ceramide salvage pathway to be enhanced. M. mulatta CL transcriptome analysis indicated in vivo relevance. Perturbing endogenous ceramide generation by fumonisin B1 (FB1) and addition of soluble ceramide (C2-CER) yielded opposite actions on viability of GCs and therefore supported the significance of the ceramide pathway. Morphological changes indicated necrotic cell death in the C2-CER treated group. Studies with the pan caspase blocker zVAD-fmk or the necroptosis blocker necrosulfonamid (NSA) further supported that C2-CER induced necroptosis. Our data pinpoint necroptosis in a physiological process, namely CL regression. This raises the possibility that the primate CL could be rescued by pharmacological inhibition of necroptosis or by interaction with ceramide metabolism.