Dean R T, Cheeseman K H
Cell Biology Research Group, Brunel University, Uxbridge, Middlesex, U.K.
Biochem Biophys Res Commun. 1987 Nov 13;148(3):1277-82. doi: 10.1016/s0006-291x(87)80271-1.
The fragmentation of the membrane protein monoamine oxidase in submitochondrial particles was induced by defined free radicals during radiolysis and by a system dependent on hydrogen peroxide and a transition metal. By injection of alpha-tocopherol in vivo, the levels of this physiological antioxidant in the mitochondrial preparations could be elevated more than ten-fold. In both radical-generating systems the presence of high levels of alpha-tocopherol in the membrane substantially retarded the protein fragmentation, in parallel with lipid peroxidation. It is suggested that membrane-bound proteins are damaged during lipid peroxidation and that alpha-tocopherol protects cells against both types of damage.
线粒体亚颗粒中的膜蛋白单胺氧化酶的片段化是由辐射分解过程中特定的自由基以及一个依赖过氧化氢和过渡金属的系统诱导产生的。通过在体内注射α-生育酚，线粒体制剂中这种生理抗氧化剂的水平可提高十倍以上。在这两种自由基生成系统中，膜中高水平的α-生育酚的存在大大延缓了蛋白质片段化，这与脂质过氧化作用是平行的。有人提出，膜结合蛋白在脂质过氧化过程中会受到损伤，而α-生育酚可保护细胞免受这两种类型的损伤。
