Hoekstra W G
Fed Proc. 1975 Oct;34(11):2083-9.
Glutathione peroxidase (glutathione:H2O2 oxidoreductase, E.C. 1.11.1.9), isolated from ovine and bovine erythrocytes, has recently been shown to contain 4 selenium atoms per mole, an average of 1 Se per protein subunit of about 22,000 molecular weight. Selenium deficiency in the rat, chick and sheep causes dramatic decreases in the activity of this enzyme in the tissues, but certain sites such as liver are affected more than others. Decreases in glutathione peroxidase correlate with lesions caused by selenium deficiency and appear useful in diagnosing selenium deficiency. Glutathione peroxidase is an important enzyme in destroying H2O2 and organic hydroperoxides such as lipid hydroperoxides. It therefore guards against oxidative damage to the cell membranes and other oxidant-sensitive sites in the cell. While this selenium-dependent system destroys lipid hydroperoxides and other peroxides, vitamin E is believed to protect against oxidant damage to membranes by preventing the formation of lipid hydroperoxides. A scheme is proposed, based on oxidant damage and its prevention, which accounts for the interaction between selenium, vitamin E, unsaturated lipids, sulfur-containing amino acids, and cell damaging agents such as oxidant stressors and toxicants such as silver and tri-o-cresyl phosphate. The background for such a scheme is reviewed.
从绵羊和牛的红细胞中分离出的谷胱甘肽过氧化物酶（谷胱甘肽：H2O2氧化还原酶，E.C. 1.11.1.9），最近已显示每摩尔含有4个硒原子，平均每个分子量约为22,000的蛋白质亚基含有1个硒原子。大鼠、小鸡和绵羊体内缺硒会导致该酶在组织中的活性急剧下降，但某些部位如肝脏受影响比其他部位更大。谷胱甘肽过氧化物酶活性的下降与缺硒引起的损伤相关，似乎有助于诊断缺硒情况。谷胱甘肽过氧化物酶是一种在破坏H2O2和有机氢过氧化物（如脂质氢过氧化物）方面的重要酶。因此，它能防止细胞膜和细胞内其他对氧化剂敏感的部位受到氧化损伤。虽然这个依赖硒的系统能破坏脂质氢过氧化物和其他过氧化物，但维生素E被认为是通过防止脂质氢过氧化物的形成来保护细胞膜免受氧化剂损伤。基于氧化损伤及其预防提出了一个方案，该方案解释了硒、维生素E、不饱和脂质、含硫氨基酸以及细胞损伤剂（如氧化应激源）和毒物（如银和磷酸三邻甲苯酯）之间的相互作用。对该方案的背景进行了综述。
