Vascular endothelial growth factor-A165 (VEGF-A165) stimulates the in vitro development and oocyte competence of goat preantral follicles

Abstract

The aim of this study was to evaluate the effect of vascular endothelial growth factor-A(165) (VEGF-A(165)) on the in vitro development of goat secondary preantral follicles. Preantral follicles (≥150μm in diameter) were isolated from the ovaries of adult mixed-breed goats and individually cultured for 18days in αMEM in the absence (control) or presence of VEGF-A(165) at concentrations of 10ng/ml (VEGF10) and 100ng/ml (VEGF100). Analyses of follicular survival, diameter, antrum formation and rate of daily growth were performed every 6days. At the end of the culture period, morphologically normal oocytes (≥110μm in diameter) were taken for in vitro maturation (IVM). The results demonstrated that all follicles presented oocytes and granulosa cells that were morphologically normal and after labeling with calcein-AM, high rates of oocyte viability were observed in all treatments. The follicular diameter and the growth rate achieved in the presence of VEGF10 were higher than those of the control. Both treatments with VEGF-A(165) showed higher rates of oocyte recovery for IVM when compared with the control. Moreover, only the addition of VEGF-A(165) permitted oocytes grown in vitro to reach metaphase II. Thus, the addition of VEGF-A(165) to the culture medium improves the development of goat preantral follicles cultured in vitro, allowing the production of mature oocytes.