Testosterone Supplementation Promotes Estrogen Synthesis of Buffalo Cumulus Cells Surrounding In Vitro -Matured Oocytes.

Cumulus cells (CCs) synthesize estrogens that are essential for follicular development. However, the effects of androgen on estrogen production in buffalo CCs remain unknown. In the present study, the impacts of testosterone on estrogen synthesis of buffalo CCs surrounding in vitro -matured oocytes were investigated. The results showed that testosterone supplementation improved both the expression levels of estrogen synthesis-related genes ( CYP11A1 , CYP19A1 , and 17β-HSD ) and the secretion levels of estradiol in buffalo CCs surrounding in vitro -matured oocytes. Furthermore, testosterone treatment enhanced the sensitivity of buffalo CCs surrounding in vitro -matured oocytes to follicle-stimulating hormone (FSH). This study indicated that testosterone supplementation promoted the estrogen synthesis of buffalo CCs surrounding in vitro -matured oocytes mainly through strengthening the responsiveness of CCs to FSH. The present study serves as a foundation of acquiring high-quality recipient oocytes for buffalo somatic cell nuclear transfer.