维生素E对苯并[a]芘诱导雄性大鼠的生殖毒性的保护作用

目的：探讨维生素E(vitamin E，VE)对苯并[a]芘(Benzo(a)pryene，B[a]P)诱导的雄性大鼠的生殖毒性的保护作用及其机制。方法：将60只28 d龄70~90 g Sprague Dawley (SD)大鼠随机分为空白、溶剂对照组、B[a]P组(5 mg/kg)及低(10 mg/kg)、中(50 mg/kg)、高(100 mg/kg)剂量VE联合B[a]P处理组共6组，每组各10只；连续灌胃30 d并检测各组精子质量、睾丸组织中超氧化物歧化酶(superoxide dismutase，SOD)和谷胱甘肽过氧化物酶(glutathione peroxidase，GSH-Px)活性、8-羟基脱氧鸟苷(8-hydroxy-2-deoxyguanosine，8-OHdG)和丙二醛(malondialdehyde，MDA)的含量；HE染色观察睾丸形态，采用彗星实验测定细胞DNA损伤程度。结果：与对照组相比，B[a]P组精子计数明显降低、精子畸形率、8-OHdG及MDA含量明显升高，SOD和GSH-Px活性显著下降(P<0.05)；VE联合组SD大鼠的睾丸组织损伤程度明显减轻；上述各项氧化应激和DNA损伤指标也均明显改善；且随着VE剂量的增加，保护效应呈现明显的剂量-反应关系，差异均具有统计学意义(P<0.05)。结论：VE对B[a]P诱导的SD雄性大鼠生殖损害具有保护作用。

Vitamin E prevents the toxic effect of benzo(a)pryene on reproductive system in male SD rats

Objective: To investigate the protective effects and the potential mechanisms of vitamin E (VE) on benzo(a)pryene (B[a]P)-induced toxicity in the reproductive system of male rats. Methods: A total of 60 male Sprague Dawley (SD) rats, weighted 70-90 g, were randomly assigned to 6 groups: a control group, a vehicle group, a B[a]P group (5 mg/kg), a VE (10 mg/kg)+ B[a]P (5 mg/kg) group, a VE (50 mg/kg) + B[a]P (5 mg/kg) group and a VE (100 mg/kg)+B[a]P (5 mg/kg) group (n=10 per group). The rats were treated with B[a]P and/or VE once a day for 30 days via intragastric administration. The sperm quality and the levels of SOD, GSH-Px, 8-OHdG and MDA were detected, respectively. The testicular tissue morphology and DNA damage were observed by HE staining and comet assay.Results: The sperm count, the rate of sperm deformation, the content of MDA and 8-OHdG were all significantly increased in single B[a]P-treated group in comparison to the control groups. The activities of SOD and GSH-Px were markedly decreased by B[a]P as compared with the control groups (P<0.05). The injury of testicular tissue in B[a]P-treated rats was remarkably improved after VE treatment. The levels of oxidative stress and DNA damage indicators in the B[a]P-treated group were all attenuated by VE. These protective effects of VE were in a dose-dependent manner (P<0.05).Conclusion: Vitamin E can protect the male SD rats against the B[a]P-induced reproductive toxicity.