Szebeni J, Eskelson C D, Chvapil M
Department of Surgery, University of Arizona, Tucson 85724.
Physiol Chem Phys Med NMR. 1988;20(3):205-11.
The effect of zinc on FeSO4/ascorbic acid-induced lipid peroxidation was measured by the thiobarbituric acid assay in various lipid systems including small unilamellar liposomes prepared from egg phosphatidylcholine (EPC), ionic micelles prepared from arachidonic acid (C20:4), non-ionic monocomponent micelles prepared from EPC-derived, methylated fatty acids, and an eicosatetrene emulsion. With the exception of C20:4 micelles, zinc inhibited lipid peroxidation in each of the above systems in a similar dose-related fashion, with 0.5 mM zinc having maximal effect. Gas-chromatographic fatty acid analysis too indicated a protective effect of zinc against FeCl3-induced lipid peroxidation in soybean PC vesicles, which do not contain C20:4 moieties. These findings, in particular the inhibition of lipid peroxidation in eicosatetrene emulsion, suggest that the presence of uncharged polar head groups, or packing of lipid molecules into ordered self-assemblages (membranes and micelles) have no critical influence on the antioxidant effect of zinc. The results with Fe2+ are compatible with the concept that zinc interferes with the formation of Fe2+-oxygen-enoic complexes. This mechanism, however, cannot account for the inhibition by zinc of the Fe#+-induced lipid peroxidation, suggesting the involvement of other types of zinc effects in these systems.
通过硫代巴比妥酸测定法，在多种脂质体系中测量了锌对硫酸亚铁/抗坏血酸诱导的脂质过氧化的影响，这些脂质体系包括由鸡蛋磷脂酰胆碱（EPC）制备的小单层脂质体、由花生四烯酸（C20:4）制备的离子型胶束、由EPC衍生的甲基化脂肪酸制备的非离子单组分胶束以及二十碳四烯酸乳液。除了C20:4胶束外，锌在上述每个体系中均以类似的剂量相关方式抑制脂质过氧化，0.5 mM锌具有最大效果。气相色谱脂肪酸分析也表明锌对大豆PC囊泡中氯化铁诱导的脂质过氧化具有保护作用，大豆PC囊泡不含C20:4部分。这些发现，特别是对二十碳四烯酸乳液中脂质过氧化的抑制，表明不带电荷的极性头部基团的存在，或脂质分子堆积成有序的自组装体（膜和胶束）对锌的抗氧化作用没有关键影响。亚铁离子的结果与锌干扰亚铁离子 - 氧 - 烯酸络合物形成的概念相符。然而，这种机制无法解释锌对铁离子诱导的脂质过氧化的抑制作用，这表明在这些体系中涉及其他类型的锌效应。
