The purpose of this study was to investigate the effects of BMP6 on the function of goat ovarian granulosa cells (GCs). The results showed that the exogenous addition of BMP6 did not affect the EdU-positive ratio of ovarian GCs and had no significant effect on the mRNA and protein expression levels of the proliferation-related gene PCNA (p > 0.05). Meanwhile, BMP6 had no significant effect on the cycle phase distribution of GCs but increased the mRNA expression of CDK4 (p < 0.05) and CCND1 (p < 0.01) and decreased the mRNA expression of CCNE1 (p < 0.01). Moreover, BMP6 had no significant effect on the apoptosis rate of GCs and did not affect the mRNA expression levels of apoptosis-related genes BAX, BCL2, and Caspase3 (p > 0.05). Importantly, BMP6 upregulated the secretion of 17 beta-estradiol (E2) and progesterone (P4) in ovarian GCs (p < 0.01). Further studies found that BMP6 inhibited the mRNA expression of 3β-HSD and steroid synthesis acute regulator (StAR) but significantly promoted the mRNA expression of the E2 synthesis rate-limiting enzyme CYP19A1 and the P4 synthesis rate-limiting enzyme CYP11A1 (p < 0.01). Taken together, these results showed that the exogenous addition of BMP6 did not affect the proliferation, cell cycle, and apoptosis of goat ovarian GCs but promoted the secretion of E2 and progesterone P4 in ovarian GCs by upregulating the mRNA expressions of CYP19A1 and CYP11A1.
Keywords: BMP6; estradiol; goat ovarian granulosa cells; progesterone.