Evaluation of Oocyte Maturation in Experimental PCOS Model

Abstract

Abstract Aim Polycystic Ovarian Syndrome (PCOS) is a complex endocrine disease and is the most common cause of infertility in women due to ovulation disorder. Although the distinctive morphological features of the polycystic ovary were clearly evaluated, the specific oocyte maturation molecules that are affect oocyte maturation and oocyte quality are currently not understood. In addition, the effect of drugs used to induce ovulation in PCOS on oocyte maturation is unknown. In this study it is aimed to investigate the changes of oocyte maturation proteins (Nobox, Foxl2, Cep55, Cx37, Cx43) post ovulation induction treatment. Materials and Methods Four-week-old, female Balb/c mice were subcutaneously injected 6mg/100g dehydroepiandrosterone (DHEA) for 21 consecutive days for experimental PCOS models and divided four groups. In control group, no injections performed. PCOS group, after DHEA administration was not applied any treatment. Treatment groups were given clomiphene citrate (1,5 mg/kg) alone or clomiphene citrate (1,5 mg/kg), metformin (12 mg/kg) and pioglitazone (0,20 mg/kg) as a combine for consecutive 5 days. The distributions of molecules were evaluated by indirect immunoperoxidase staining method in ovarian tissues and immunofluorescence staining method for oocytes. Intensity of immunofluorescence evaluated by ImageJ. Results The formation of the PCOS model was demonstrated by the glucose tolerance test, histological and morphological evidence. It was determined that the expression of all investigated molecules significantly decreased in the ovarian tissues of PCOS group but increased in the treated groups. In oocytes, intensities of Nobox, Foxl2, Cep55 and Cx43 were significantly increased in clomiphene citrate administered group compared to the PCOS group. Conclusion This study is the first to investigate the effect of drugs used for providing ovulation induction and reducing insulin resistance as single or combined treatments in PCOS mice model through maturation molecules. Both in vivo and in vitro oocyte maturation may trigger with target-specific treatment in PCOS patients. In addition, new molecules could be used in control of the in vitro oocyte maturation during treatment.