维生素E拮抗双酚A对卵巢颗粒细胞性激素分泌的抑制作用

Vitamin E could reverse effects of bisphenol A on steroidogenesis in rat ovary granulosa cells

目的·研究维生素E能否对双酚A(BPA)的雌性性激素干扰效应起拮抗作用,探索拮抗作用的适宜浓度。方法·提取大鼠卵巢原代颗粒细胞。不同浓度BPA(0、0.01、0.1、1、10、100μmol/L)孵育48 h后,收集并用ELISA法测定细胞培养基中的雌二醇(E_2)及孕酮(P_4)浓度。采用健康女性卵泡液中的平均浓度(简称"人体平均浓度",5μmol/L)或高浓度(25μmol/L)维生素E(α-生育酚)单独孵育或与BPA(10、100μmol/L)共同孵育颗粒细胞48 h后,测定培养液中性激素浓度。结果·10μmol/L及100μmol/L BPA可使大鼠原代卵巢颗粒细胞分泌性激素水平呈浓度依赖性降低(P<0.05)。25μmol/L维生素E单独孵育时可分别使E_2和P_4浓度显著升高(44.89±15.18)%和(43.33±8.82)%(P<0.05);维生素E(5μmol/L或25μmol/L)和BPA共同孵育时,性激素浓度恢复正常,与阴性对照组相比,差异无统计学意义(P>0.05)。结论·人体平均浓度及高浓度维生素E均可拮抗BPA导致的性激素降低效应,而高浓度维生素E的改善效果相对显著。

Objective · To investigate whether vitamin E could reverse the disruptive effects of bisphenol A （BPA） on steroidogenesis and to explore the optimal vitamin E concentration. Methods · Rat primary granulosa cells were extracted and exposed to BPA （0, 0.01, 0.1,1,10,100 μmol/L）. After 48 h of incubation, culture medium was collected and estradiol （E2） and progesterone （P4） were measured using ELISA kits. Then, granulosa cells were incubated with 5 μmol/L（average concentration in follicular fluid） or 25 μmol/L （high concentration in follicular fluid） vitamin E （α-tocopherol） or vitamin E （5 μmol/ L or 25 μmol/L） plus BPA （10 μmol/L or 100 μmol/L） for 48 h, E2 and P4 were measured. Results · BPA at 10 μmol/L and 100 μmol/L suppressed E2 and P4 production in a dose-dependent manner （P〈0.05）. Vitamin E at 25 μmol/L significantly increased E2 and P4 levels by （44.89±15.18） % and （43.33±8.82） % （P〈0.05）, respectively. Coincubation of the granulosa cells with BPA and vitamin E （5 μmol/L or 25 μmol/L） restored the productions of E2 and P4, which were not significantly different from the control group （P〉0.05）. Conclusion · Vitamin E （5 μmol/L/ 25 μmol/L） could reverse BPA-induced reduction in steroid hormone production in rat ovary granulosa cells, and the antagonistic effect of 25 μmol/L vitamin E was more obvious than that of 5 μmol/L vitamin E.