A histological and biochemical study of cumulus cells and the oocyte microenviroment in in vitro fertilization patients

Objectives: The aim of this study was to investigate the effect of chemical changes in the follicular fluid and histologi-cal changes in the cumulus cells of the oocyte microenvironment on the number of oocytes in infertile patients. Methods: A total of 50 female patients aged 18-35 who presented at the Atatürk University Research Hospital Infertility Clinic and for infertility treatment were included. The patients were divided into 3 groups: Patients with fewer than 5 oocytes were classified as Group 1, patients with 5-20 oocytes comprised Group 2, and Group 3 was made up of patients with >20 oocytes. During the oocyte collection process, follicular fluid was aspirated from the follicles and the cumulus cells were collected. The follicular fluid was stored at-80°C for use in biochemical analysis of malondialde-hyde (MDA), total antioxidant status (TAS), total oxidant status (TOS), superoxide dismutase (SOD), glutathione (GSH). Immunohistochemical staining was performed to examine caspase-3 and mechanistic target of rapamycin (mTOR) immunoreactivity at the stereological level. Results: The MDA level and total oxidant capacity (TOC) in the follicular fluid were higher in Group 1 patients than in the other 2 groups, while the SOD was lower (p<0.05). In Group 2 patients, the MDA level and TOS were higher than those of Group 3, while the SOD level was lower (p<0.05). The total antioxidant capacity (TAC) and GSH levels did not vary significantly according to the number of oocytes (p<0.05). Immunohistochemical staining showed that mTOR and caspase-3 immunoreactivity were more intense in Group 1 than in the other groups. Conclusion: The increase in mTOR expression may activate the caspase-3 pathway, which could lead to oxidative stress. The mTOR pathway may affect the oocyte count. © 2021 by International Journal of Medical Biochemistry.