First pregnancy after in vitro culture of early antral follicles in goats: Positive effects of anethole on follicle development and steroidogenesis.

Abstract

This study aimed to evaluate the role of anethole during the in vitro culture of caprine early antral follicles. Early antral follicles were isolated from caprine ovaries and cultured for 18 days without (control) or with anethole (300 µg/ml). After culture, the cumulus-oocyte complexes were subjected to in vitro maturation, followed by parthenogenetic activation or in vitro fertilization (IVF) and embryo culture. Follicular walls were used for the quantification of messenger RNA (mRNA) of CYP19A1, CYP17, MMP-9, TIMP-2, Bax, and Bcl-2 genes, and culture medium was used for evaluation of ferric reducing antioxidant power (FRAP) and estradiol levels. After in vitro follicle culture (IVFC), anethole induced higher total antioxidant capacity, that is, it produced higher FRAP levels, reduced the Bax/Bcl-2 ratio, and increased the levels of mRNA for CYP19A1 and CYP17, which was associated with a greater estradiol production (p < .05). Also, anethole improved the ability of oocytes to resume meiosis and reach metaphase II stage, as well as yielded higher (p < .05) embryo production (e.g., morulas and blastocysts) in both parthenogenetic activation and IVF techniques. One pregnancy (Day 30) was obtained from IVFC with anethole. In conclusion, anethole promoted in vitro growth and maturation of goat early antral follicles and oocytes and enabled embryo production. Furthermore, this study reports, for the first time in goats, a pregnancy after IVF using oocytes originated from early antral follicles grown in vitro.