Maiorino M, Zamburlini A, Roveri A, Ursini F
FEBS Lett. 1993 Sep 13;330(2):174-6. doi: 10.1016/0014-5793(93)80267-x.
When exposed to Cu2+, alpha-tocopherol, in detergent dispersion, is rapidly oxidised. Moreover, if phospholipids and traces of their hydroperoxide derivatives are included in these dispersions, Cu2+ initiates lipid peroxidation, the rate of which is dramatically stimulated by alpha-tocopherol. The observation that the rate of alpha-tocopherol consumption is identical in the absence and in the presence of lipids undergoing peroxidation, apparently rules out any antioxidant effect. These results are consistent with a prooxidant effect of vitamin E, mediated by its capability to reduce Cu2+ to Cu+ which, in turn, produces, from lipid hydroperoxides, the highly reactive alkoxyl radicals. Present data highlight the risk of misleading results in interpreting the significance of lags in peroxidation of LDL challenged with Cu2+.
当暴露于Cu2+时，去污剂分散液中的α-生育酚会迅速被氧化。此外，如果这些分散液中含有磷脂及其氢过氧化物衍生物的痕量物质，Cu2+会引发脂质过氧化，α-生育酚会显著加速其速率。在脂质过氧化存在和不存在的情况下，α-生育酚消耗速率相同这一观察结果，显然排除了任何抗氧化作用。这些结果与维生素E的促氧化作用一致，该作用由其将Cu2+还原为Cu+的能力介导，而Cu+又从脂质氢过氧化物中产生高活性的烷氧基自由基。目前的数据突出了在解释用Cu2+刺激的低密度脂蛋白（LDL）过氧化过程中延迟的意义时得出误导性结果的风险。
