自由基、抗氧化防禦與人體健康

Free Radicals, Antioxidant Defenses and Human Health

陳惠英(Hui-Yin Chen) ； 顏國欽(Gow-Chin Yen)

《中華民國營養學會雜誌》 23卷1期 (1998/02) Pp. 105-121

https://doi.org/10.6691/JCNS.199802_23(1).0009

摘要

近年來的研究指出自由基在許多疾病的發展上扮演相當重要的角色，包括老化、癌症和心血管疾病等。人體在正常代謝過程會產生活性氧與自由基，當體內的多元不飽和脂肪酸受到自由基攻擊而氧化時，會形成更多的自由基。所產生的活性氧和自由基會攻擊包括蛋白質、酵素、醣類、脂質、DNA和RNA等分子，而造成細胞的傷害。含氧自由基對生物體細胞和分子的傷害與許多疾病有關，因此瞭解活性氧與自由基會對體內分子造成何種傷害，在疾病的發展與預防上是相當重要的。雖然活性氧與自由基會造成生物體分子的損傷，甚至導致疾病產生，但在正常狀況下，生物體中具有抗氧化防禦系統，包括抗氧化酵素及抗氧化物來移除活性氧與自由基，並由修復系統修補自由基所引發之傷害。然而此種氧化與抗氧化之間的平衡會因疾病或營養不良而受到破壞，傾向氧化的一邊，造成氧化壓力之形成。因此抗氧化物在預防氧化傷害甚至疾病的危害上乃逐漸受到重視，在本文中將詳加敘述自由基與抗氧化物對於人體健康之影響。

關鍵字

自由基 ； 活性氧 ； 氧化壓力 ； 抗氧化物

並列摘要

In recent years, a considerable number of studies have indicated the important role of free radicals in the progress of many human diseases, including aging, cancer and cardiovascular disease. Activated oxygens and free radicals are formed in the normal metabolic processes of human tissue, and more are derived from the oxidation of polyunsaturated fatty acids attacked by free radicals. The attacks of activated oxygens and free radicals on protein, enzyme, carbohydrate, lipid, DNA and RNA induce cell damage, resulting in the development of diseases. Therefore, to realize what kind damage of activated oxygens and free radicals invoke on biological molecules is important in the study of progress and prevention of diseases. Although activated oxygens and free radicals cause injury of biological molecules, and even result in the development of diseases, they are scavenged by antioxidative enzymes and antioxidants, and the damaged molecules will be repaired by the repair systems. However, the balance between oxidation and antioxidant action will alter the oxidative condition due to illness or malnutrition, and resulting in oxidative stress. Hence, much attention has been focused on the role of antioxidants in the prevention of oxidative damage and diseases. The effects of free radicals and antioxidants on human health are discussed in this article.

並列關鍵字

free radicals ； reactive oxygen species ； oxidative stress ； antioxidants