Department of Physiology, Endocrinology and Reproductive Physiology Laboratory, University of Calcutta, Kolkata, West Bengal, India.
Food Chem Toxicol. 2010 Mar;48(3):972-9. doi: 10.1016/j.fct.2010.01.008. Epub 2010 Jan 16.
Excess chromium (Cr) exposure is associated with various pathological conditions including reproductive dysfunction. Generation of oxidative stress is one of the plausible mechanisms behind Cr induced cellular deteriorations. The efficacy of vitamin E to combat Cr induced oxidative damage in adult rat testis has investigated in the current study. Adult male rats exposed to hexavalent Cr (intraperitoneal injection with 0.4 mg K(2)Cr(2)O(7)/ kg bw/day) for 26 days resulted in decreased accessory sex organs weight compared to controls. Development of oxidative stress in testis was evidenced by increased lipid peroxidation along with decreased superoxide dismutase (SOD) and catalase activities than control animals. Marked reduction in the activities of testicular steroidogenic enzymes; Delta(5)3beta-hydroxysteroid dehydrogenase (HSD), 17beta-HSD, serum testosterone and Leutinizing Hormone (LH) levels were observed. However significant increase in serum Follicle Stimulating Hormone (FSH) level was observed with Cr treated group. Histological evaluation of testis revealed degeneration of stage VII spermatogenic cycle along with decrease in epithelial cell height in epididymis and seminiferous tubules; number of different germ cells per seminiferous tubule and seminiferous tubular diameter reduced after Cr exposure. Simultaneous oral supplementation of vitamin E (50mg/kg bw/day) in Cr exposed rats showed less oxidative damage and restored the otherwise altered testicular activities. Epididymal sperm number was also restored in vitamin E-supplemented group than Cr induced rats. This study implicates vitamin E as a possible protective agent against Cr induced spermatogenic and steroidogenic alteration.
过量的铬(Cr)暴露与各种病理状况有关,包括生殖功能障碍。产生氧化应激是 Cr 引起细胞恶化的一种合理机制。本研究探讨了维生素 E 对成年大鼠睾丸 Cr 诱导的氧化损伤的作用。成年雄性大鼠经腹腔注射六价 Cr(每天 0.4mg K2Cr2O7/kg bw)26 天后,与对照组相比,附性器官重量下降。睾丸氧化应激的发展表现为脂质过氧化增加,同时超氧化物歧化酶(SOD)和过氧化氢酶活性降低。与对照组动物相比,睾丸甾体生成酶的活性显著降低;Delta(5)3beta-羟甾类脱氢酶(HSD)、17beta-HSD、血清睾酮和促黄体激素(LH)水平降低。然而,Cr 处理组的血清卵泡刺激素(FSH)水平显著升高。睾丸组织学评价显示,VII 期精子发生周期退化,附睾和曲细精管上皮细胞高度降低;Cr 暴露后,每个曲细精管的不同生殖细胞数量和曲细精管直径减少。Cr 暴露大鼠同时口服补充维生素 E(50mg/kg bw/天)可减少氧化损伤,并恢复其他改变的睾丸功能。补充维生素 E 组的附睾精子数量也恢复到 Cr 诱导组的水平。本研究表明,维生素 E 可能是一种对抗 Cr 诱导的生精和甾体生成改变的保护剂。