论文部分内容阅读
人体自然衰老与包括肿瘤、心血管病等疾病在内的退行性疾病都有一个共同的发生过程,即细胞受到氧自由基的氧化损害。当机体处于过度氧化负荷下活性氧形成过多,抗氧化物质耗竭或活性下降。活性氧具有极为活泼的单电子,易与亲核性的DNA分子结合,发生DNA氧化损伤及随之发生修复错误,可导致癌基因的激活或抑癌基因的失活,形成DNA碱基的改变,8-羟基(脱氧)鸟嘌呤(8-OHdG)是最有代表性的DNA氧化损伤产物;氧化损伤可导致酶活性的诱导或抑制、DNA和蛋白质之间的交联,引起遗传特性改变及蛋白质功能丧失或改变;细胞膜蛋白的损伤不仅破坏细胞膜的通透性,引起细胞内外离子浓度的失
Natural aging and including cancer, cardiovascular disease and other diseases, including degenerative diseases have a common occurrence, that is, cells are oxidative damage by oxygen free radicals. When the body is over-oxidized load excessive formation of reactive oxygen species, antioxidant depletion or decreased activity. Active oxygen has a very lively single-electron, easily with the nucleophilic DNA molecules, the occurrence of DNA oxidative damage and subsequent repair errors, can lead to oncogene activation or tumor suppressor gene inactivation, the formation of DNA base changes , 8-OH (deoxy) guanine (8-OHdG) is the most representative product of oxidative DNA damage; oxidative damage can lead to induction or inhibition of enzyme activity, DNA and protein cross-linking, causing genetic changes and Loss or alteration of protein function; damage to the cell membrane protein not only disrupts the permeability of the cell membrane, causing the loss of intra- and extracellular ion concentrations