Packer L, Witt E H, Tritschler H J
Department of Molecular & Cell Biology, University of California, Berkeley 94720, USA.
Free Radic Biol Med. 1995 Aug;19(2):227-50. doi: 10.1016/0891-5849(95)00017-r.
alpha-Lipoic acid, which plays an essential role in mitochondrial dehydrogenase reactions, has recently gained considerable attention as an antioxidant. Lipoate, or its reduced form, dihydrolipoate, reacts with reactive oxygen species such as superoxide radicals, hydroxyl radicals, hypochlorous acid, peroxyl radicals, and singlet oxygen. It also protects membranes by interacting with vitamin C and glutathione, which may in turn recycle vitamin E. In addition to its antioxidant activities, dihydrolipoate may exert prooxidant actions through reduction of iron. alpha-Lipoic acid administration has been shown to be beneficial in a number of oxidative stress models such as ischemia-reperfusion injury, diabetes (both alpha-lipoic acid and dihydrolipoic acid exhibit hydrophobic binding to proteins such as albumin, which can prevent glycation reactions), cataract formation, HIV activation, neurodegeneration, and radiation injury. Furthermore, lipoate can function as a redox regulator of proteins such as myoglobin, prolactin, thioredoxin and NF-kappa B transcription factor. We review the properties of lipoate in terms of (1) reactions with reactive oxygen species; (2) interactions with other antioxidants; (3) beneficial effects in oxidative stress models or clinical conditions.
α-硫辛酸在线粒体脱氢酶反应中发挥着重要作用，最近作为一种抗氧化剂受到了广泛关注。硫辛酸或其还原形式二氢硫辛酸能与超氧自由基、羟基自由基、次氯酸、过氧自由基和单线态氧等活性氧物种发生反应。它还通过与维生素C和谷胱甘肽相互作用来保护细胞膜，而维生素C和谷胱甘肽反过来又可能使维生素E循环利用。除了抗氧化活性外，二氢硫辛酸还可能通过还原铁发挥促氧化作用。在许多氧化应激模型中，如缺血再灌注损伤、糖尿病（α-硫辛酸和二氢硫辛酸都能与白蛋白等蛋白质发生疏水结合，从而防止糖基化反应）、白内障形成、HIV激活、神经退行性变和辐射损伤，给予α-硫辛酸已显示出有益效果。此外，硫辛酸可作为肌红蛋白、催乳素、硫氧还蛋白和核因子κB转录因子等蛋白质的氧化还原调节剂。我们从以下几个方面综述硫辛酸的特性：（1）与活性氧物种的反应；（2）与其他抗氧化剂的相互作用；（3）在氧化应激模型或临床状况中的有益作用。
