Local effect of bisphenol A on the estradiol synthesis of ovarian granulosa cells from PCOS

Close relationship between polycystic ovary syndrome (PCOS) and bisphenol A (BPA) has drawn much attention in recent years, while the underlying mechanisms are poorly understood. In our study, we aim to detect BPA concentration in the follicular fluid and investigate its effect on estradiol synthesis in human granulosa cells from PCOS and non-PCOS patients. Follicular fluid and granulosa cells were collected from women who underwent controlled ovarian stimulation for in vitro fertilization or intracytoplasmic sperm injection. BPA concentration in the follicular fluid from PCOS patients (440.50 ± 63.70 pg/ml) was significantly higher than that from non-PCOS patients (338.00 ± 57.88 pg/ml). Expression of aromatase and estradiol synthesis in cultured granulosa cells was examined after treatment with BPA from 0.01 to 1 μM for 24 h. Expression of aromatase and estradiol synthesis was downregulated by BPA in a dose-dependent manner in PCOS, but no effect was observed in granulosa cells from non-PCOS patients. These findings provide evidence that increased BPA concentration in the follicular fluid of PCOS patients may play an important role in its pathogenesis by attenuating the expression of aromatase in granulosa cells.