UBIQUINOL-10 IS AN EFFECTIVE LIPID-SOLUBLE ANTIOXIDANT AT PHYSIOLOGICAL CONCENTRATIONS
UBIQUINOL-10 IS AN EFFECTIVE LIPID-SOLUBLE ANTIOXIDANT AT PHYSIOLOGICAL CONCENTRATIONS
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DOI：
10.1073/pnas.87.12.4879
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发表时间：
1990-06-01
影响因子：
11.1
通讯作者：
AMES, BN
中科院分区：
文献类型：
--
作者：
FREI, B;KIM, MC;AMES, BN
众所周知，辅酶Q10、辅酶50是线粒体呼吸链的电子载体。在这篇论文中，我们证明了泛醌-10的简化形式，也有效地清除脂膜中化学生成的自由基。泛喹酚-10在防止脂质过氧化损伤方面与α-生育酚一样有效，后者被认为是人类最好的脂溶抗氧化剂。在我们的实验条件下，每个泛喹酚-10分子的自由基数为1.1。与α-生育酚不同的是，泛喹酚-10不被抗坏血酸循环利用。然而，已知泛喹酚-10可以被存在于各种生物膜上的电子传输载体回收，也可能被一些酶回收。我们还表明，当两种抗氧化剂都存在于相同的脂质体膜中时，泛喹酚-10可以替代α-生育酚，并且泛喹酚-10和α-生育酚一样，不与还原型谷胱甘肽相互作用。我们的数据与文献中报道的泛喹酚的抗氧化功能相结合，有力地表明泛喹酚-10是一种重要的生理脂溶抗氧化剂。
It is well known that ubiquinone-10 (coenzyme Q10, ubiquinone 50) acts as an electron carrier of the respiratory chain in mitochondria. In this paper we show that ubiquinol-10, the reduced form of ubiquinone-10, also efficiently scavenges free radicals generated chemically within liposomal membranes. Ubiquinol-10 is about as effective in preventing peroxidative damage to lipids as .alpha.-tocopherol, which is considered the best lipid-soluble antioxidant in humans. The number of radicals scavanged by each molecule of ubiquinol-10 is 1.1 under our experimental conditions. In contrast to .alpha.-tocopherol, ubiquinol-10 is not recycled by ascorbate. However, it is known that ubiquinol-10 can be recycled by electron transport carriers present in various biomembranes and possibly by some enzymes. We also show that ubiquinol-10 spares .alpha.-tocopherol when both antioxidants are present in the same liposomal membranes and that ubiquinol-10, like .alpha.-tocopherol, does not interact with reduced glutathione. Our data together with previous work on the antioxidant function of ubiquinol reported in the literature strongly suggest that ubiquinol-10 is an important physiological lipid-soluble antioxidant.