Antioxidative enzyme-related gene expression levels in cumulus cells during in vitro fertilization: A comparison between normal and poor ovarian responders

Abstract

Background: Preeminent interfering factor caused in vitro fertilization (IVF) failure has been broadly emphasized on poor ovarian response (POR) to controlled ovarian hyperstimulation (COH). The specific etiology and precise infertility treatment in POR patients, until now, has not been established and leads to detrimental effects on physical or psychological patient life qualities. To date, one biological stress phenomena, oxidative stress, is broadly implicated in varieties of female reproductive pathological conditions including poor oocyte quantity and quality. Hence, the present study is principally aimed to investigate oxidative stress scavenging system; enzymatic antioxidant-related gene expression level (SOD1, SOD2 and GPx4), in cumulus cells retrieved from poor ovarian responders (POR) and normal ovarian responders (NOR).Methods: A cross-sectional analytic study; fifty-six infertile women, aged between 25-49 years-old who underwent IVF procedure, were enrolled into this study with 28 participants in POR group (1-4 retrieved oocytes) and 28 participants in NOR group (5-15 oocytes). The cumulus cells from first punctured follicle were processed for mRNA gene expression levels of enzymatic antioxidant-related genes (Superoxide dismutase: SOD1, SOD2 and Glutathione peroxidase: GPx4) by quantitative real-time PCR (qPCR) and their association to other reproductive biological factors.Results: The relative mRNA expression of SOD1, SOD2 and GPx4 neither differed between poor and normal responders nor correlated with other relevant reproductive biological cohorts. However, the relative SOD2 mRNA expression level in patients who received human menopausal gonadotropin (hMG) was notably higher than the recombinant follicle stimulating hormone (rFSH) group (P = 0.017).Conclusions: Our major findings indicated that the enzymatic antioxidant-related gene mRNA expression in the cumulus cells do not associate with the ovarian response and other clinical outcomes (i.e. fertilization and pregnancy rates) after IVF procedure. However, the enzymatic antioxidant-related genes positively relate with type of gonadotropin administration.