| 产品介绍 |
Organisms generate oxygen radicals by enzyme system and non-enzyme system, oxygen radicals will attack polyunsaturated fatty acid (PUFA) to initiate lipid peroxidation, as result, lipid peroxides such as aldehyde group (MDA), ketone group, hydroxyl group, carbonyl group, hydroperoxy radical or endoperoxy radical, and new oxygen radical, etc. Lipid peroxidation not only convert active oxygen to active chemicals (nonradical lipid decomposed product) but also amplify effect of active oxygen by chain reaction and branched chain reaction. Thus a primary active oxygen can lead to many lipid decomposed products, some of them are unharmful but others can cause cellular dysmetabolism and dysfunction or even cell death. Oxygen radicals cause cell damage by not only PUFA peroxidation but also lipid hydroperoxide decomposition products. As result, MDA content always reflects lipid peroxidation level in vivo, it can also reflect cell damage level indirectly.
Generally, MDA assay can go with SOD assay, SOD activity reflects oxygen radical removing abilility in vivo indirectly, MDA content reflects severity level of free radical attacking on body cells. Analysis on account of SOD & MDA results is helpful for developments of medical science, biology, pharmacology, industry and agriculture.
机体通过酶系统与非酶系统产生氧自由基，后者能攻击生物膜中的多不饱和脂肪酸，引发脂质过氧化作用，并因此形成脂质过氧化物。如：醛基（丙二醛MDA）、酮基、羟基、羰基、氢过氧基或内过氧基，以及新的氧自由基等。脂质过氧化作用不仅把活性氧转化成活性化学剂，即非自由基性的脂类分解产物，而且通过链式或链式支链反应，放大活性氧的作用。因此，初始的一个活性氧能导致很多脂类分解产物的形成，这些分解产物中，一些是无害的，另一些则能引起细胞代谢及功能障碍，甚至死亡。氧自由基不但通过生物膜中多不饱和脂肪酸的过氧化引起细胞损伤，而且还能通过脂氢过氧化物的分解产物引起细胞损伤。因而测试 MDA的量常常可反映机体内脂质过氧化的程度，间接地反映出细胞损伤的程度。MDA的测定常常与SOD的测定相互配合，SOD活力的高低间接反应了机体清除氧自由基的能力，而MDA的高低又间接反应了机体细胞受自由基攻击的严重程度，通过SOD与MDA的结果分析有助于医学、生物学、药理及工农业生产的发展。
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