An in vitro Study of Follicle Stimulating Hormone (FSH) and α-tocopherol Effects on the Maturation of Preantral Follicle-Enclosed Oocytes from Immature Mice

In vitro maturation (IVM) of oocyte is a promising technique to reduce the costs and avert the side effects of gonadotropin stimulation for in vitro fertilization (IVF). To better characterize the nature and impact of different hormones and important parameters on the growth and in vitro maintenance of oocyte, the present study was done. The purpose of this study is in vitro investigation of follicle stimulating hormone (FSH) and α-tocopherol effects on the maturation of preantral follicle-enclosed oocytes from immature mice Intact preantral follicles were isolated from the ovaries of 6-week-old female mice and cultured in TCM-199 medium. Preantral follicles of immature mice were studied during a culture period of 6 days in the presence of 5, 20, 40, 60, 100, 140, 180 and 220 mIU/ml FSH and 20, 40, 80, 240, 300 and 400 nmol/ml of α-tocopherol (vitamin E). Follicles were cultured in an incubator at 37 °C, 92 % humidity and 5% CO2 in air. The effects of several materials were surveyed on follicle diameter, survival, germinal vesicle breakdown (GVBD) and oocyte maturation rates. Our study was experimental. The entire statistical analysis was carried out using the Statistical Package for Social Sciences (SPSS version 14.0) and one-way ANOVA. 100 IU/l FSH showed a significant increase in follicle diameter (190 ± 5µm), survival (91% ± 4), germinal vesicle breakdown (GVBD) (81% ± 3) and oocyte maturation rates (59% ± 6). Vitamin E showed an increase in survival rate but unaffected diameter, GVBD and oocyte maturation rates. The medium containing α-tocopherol and FSH showed a marked increase in all parameters including follicle diameter (210 ± 5µm), survival (95% ± 3), germinal vesicle breakdown (GVBD) (93% ± 3) and oocyte maturation rates (76% ± 5). It is concluded that FSH and α-tocopherol increase the maturation rate of follicles and enclosed oocytes, but if they are supplied in a combination, this growth rate can increase more significantly.