comparison of mouse ovarian follicular development and gene expression in the presence of ovarian tissue extract and sodium selenite: an experimental study

Background: ovarian tissue extract (ote) and sodium selenite (ss) enhance the growth and maturation of preantral follicles in a dose-dependent manner. objective: the present study was designed to bring more information regarding the mechanism of ote and ss on the mrna expression of follicle-stimulating hormone receptors (fshr) and the proliferation cell nuclear antigens (pcna) of in vitro matured isolated follicles.materials and methods: the tissue extract was prepared from adult ovaries. the preantral follicles (n = 266) were isolated from 12-16-day-old mice and cultured in the control, experimental i (10 ng/ml ss), and experimental ii (ote) groups for 12 days. the follicular diameter, survival, and maturation rates, also, the production of 17-β-estradiol and progesterone, and the follicular expression of pcna and fsh receptor genes were analyzed. results: the survival rate of follicles in the ss-treated group (84.58%) was significantly higher than that ote (75.63%; p = 0.023) and control (69.38%; p = 0.032) groups. the mean diameter of culture follicles in experimental group i (403.8 μm) and experimental group ii (383.97 μm) increased significantly in comparison with the control group (342.05 μm; p = 0.032). the developmental rate of follicles, percentages of antrum formation, released metaphase ii oocytes (p = 0.027; p = 0.019 respectively), production of hormones and the expression of 2 studied genes were significantly increased in both experimental groups in compare with control group (p = 0.021; p = 0.023 respectively).conclusion: the ote and ss have a positive effect on development of mouse preantral follicles via over-expression of fshr and pcna genes.