The antioxidant properties of zinc
The antioxidant properties of zinc
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DOI：
10.1093/jn/130.5.1447s
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发表时间：
2000-05-01
影响因子：
4.2
通讯作者：
Powell, SR
中科院分区：
文献类型：
--
作者：
Powell, SR
锌延缓氧化过程的能力已被认识多年。一般来说，抗氧化机制可分为急性和慢性作用。慢性效应涉及生物体长期暴露于锌，导致诱导一些其他物质，如金属硫蛋白，这是最终的抗氧化剂。慢性锌缺乏通常会导致对某些氧化应激的敏感性增加。急性效应涉及两种机制：保护蛋白质巯基或减少（OH）-O-。通过氧化还原活性过渡金属如铁和铜的拮抗作用从H2 O2形成。蛋白质巯基的保护被认为涉及通过以下三种机制之一降低巯基反应性：（1）锌与巯基的直接结合，（2）由于与巯基附近的一些其他蛋白质位点结合而产生的空间位阻，或（3）与蛋白质上的一些其他位点结合的构象变化。氧化还原活性的、过渡金属催化的、位点特异性反应的拮抗作用导致了锌可能能够减少细胞损伤的理论，所述细胞损伤可能具有位点特异性氧化损伤的组分，例如缺血后组织损伤。锌能够通过可能涉及铜反应性拮抗作用的机制来减少对多种组织和器官的缺血后损伤。虽然锌的抗氧化特性的证据是令人信服的，但其机制仍不清楚。未来探索这些机制的研究可能会开发锌的新抗氧化功能和用途。
The ability of zinc to retard oxidative processes has been recognized for many years. In general, the mechanism of antioxidation can be divided into acute and chronic effects. Chronic effects involve exposure of an organism to zinc on a long-term basis, resulting in induction of some other substance that is the ultimate antioxidant, such as the metallothioneins. Chronic zinc deprivation generally results in increased sensitivity to some oxidative stress. The acute effects involve two mechanisms: protection of protein sulfhydryls or reduction of (OH)-O-. formation from H2O2 through the antagonism of redox-active transition metals, such as iron and copper. Protection of protein sulfhydryl groups is thought to involve reduction of sulfhydryl reactivity through one of three mechanisms: (1) direct binding of zinc to the sulfhydryl, (2) steric hindrance as a result of binding to some other protein site in dose proximity to the sulfhydryl group or (3) a conformational change from binding to some other site on the protein. Antagonism of redox-active, transition metal-catalyzed, site-specific reactions has led to the theory that zinc may be capable of reducing cellular injury that might have a component of site-specific oxidative damage, such as postischemic tissue damage. Zinc is capable of reducing postischemic injury to a variety of tissues and organs through a mechanism that might involve the antagonism of copper reactivity. Although the evidence for the antioxidant properties of zinc is compelling, the mechanisms are still unclear. Future research that probes these mechanisms could potentially develop new antioxidant functions and uses for zinc.