Effects of different concentrations of concanavalin A and follicle stimulating hormone on goat primordial follicles activation, survival and gene expression

This study aims to investigate the effects of concanavalin A (Con A) and follicle stimulating hormone (FSH) on the survival and activation of primordial follicles, as well as on gene expression in cultured goat ovarian tissue. Ovarian tissues were cultured for one or six days in medium supplemented with different concentrations of Con A (0, 5, 10, 20 and 40 μg/mL – experiment 1). Non-cultured (control) and ovarian fragments cultured for one or six days were processed for histological evaluation. After choosing the best concentration of Con A (10 μg/mL), ovarian tissues were cultured for 6 days in medium supplemented with Con A (10 μg/mL), FSH (50 ng/mL) or both (experiment 2). Then, the ovarian fragments were processed for histology, or stored to evaluate the expression of the mRNAs for PCNA, c-kit, KL, GDF-9 and BMP-15 by PCR in real time. The results showed that after 6 days of culture, the presence of Con A (10 or 40 μg/mL) was effective in maintaining the percentage of normal follicles and in promoting primordial follicle activation. The addition of FSH (50 ng/mL) alone or in combination with Con A (10 μg/mL) was able to induce the primordial follicles activation, but no positive interaction was observed. However, after culture, FSH increased the expression of PCNA mRNA, but this effect was blocked by Con A. Con A increased the levels of c-KIT mRNA in relation to uncultured control, but Con-A or both Con A and FSH reduced the levels of KL mRNA. In addition, a reduction of BMP-15 mRNA expression was found in follicles cultured in control medium, but not in media containing FSH. Furthermore, follicles cultured in presence of Con A had higher levels of mRNA for GDF-9 than those cultured in control medium. In conclusion, Con A and FSH are able to improve goat primordial follicles activation and regulate gene expression in ovarian cortical tissue that was cultured for 6 days.