Tocopherylquinone (TQ) is formed in the antioxidant action of tocopherol (T). TQ was found in human subjects and it was observed that the ratio alphaTQ/ alphaT increased in general with increasing oxidative stress. TQ is reduced to tocopheryl hydroquinone (TQH2) but the ratio TQH2/TQ in vivo has not been reported. TQH2 acts as a potent radical-scavenging antioxidant. alphaTQH2 is more reactive toward radicals than ubiquinol, a reduced form of coenzyme Q, and alphaT. The overall efficacy of TQH2 as an antioxidant is determined by the fate of semiquinone radical formed from TQH2 as well as the reactivity toward oxygen radicals. Partly substituted gammaTQ, but not alphaTQ, exerts cytotoxicity by both redox cycling and reaction with protein thiols and glutathione.

中文翻译：

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生育酚醌和生育酚氢醌。

生育酚醌（TQ）是在生育酚（T）的抗氧化作用中形成的。在人类受试者中发现了TQ，并且观察到αTQ/αT的比率通常随着氧化应激的增加而增加。TQ还原为生育酚对苯二酚（TQH2），但尚未报道体内TQH2 / TQ的比率。TQH2用作有效的自由基清除抗氧化剂。与泛醇，辅酶Q和αT的还原形式相比，αTQH2对自由基的反应性更高。TQH2作为抗氧化剂的整体功效取决于TQH2形成的半醌自由基的命运以及对氧自由基的反应性。部分取代的gammaTQ（而非alphaTQ）通过氧化还原循环以及与蛋白质硫醇和谷胱甘肽的反应而发挥细胞毒性作用。