[Antioxidant vitamins--significance for preventing cardiovascular diseases. Part 1. Oxidized low-density lipoproteins and atherosclerosis; antioxidant dietary supplementation--vitamin E]

Abstract

The knowledge that an oxidizing of LDL is necessary for the foam cell formation is in the basis of the so called oxidative hypothesis of atherosclerosis. The role of LDL-oxidation for the atherosclerotic plaque formation, as well as its association with inflammatory processes in the vascular wall, are well established. The important conclusion of this hypothesis is the possible role of the antioxidants attenuating atherosclerotic mechanisms. The advances in studying the principal antioxidant vitamins E, C and beta-carotene effects, revealed a great part of their molecular mechanisms, which are not necessarily antioxidative. The important aspects of the cooperative antioxidant action are revealed too, including the so called tocopherol-mediated peroxidation, suggesting the need of the co-antioxidants for effective antioxidant defense. In the recent years many vitamin antioxidant supplementations are used. The epidemiological results of such supplementation do not always reveal the same beneficial effects as expected theoretically or based on the observations made with diet rich in fruits and vegetables. The present paper generalizes the thought concerning the impact of oxidized LDL in atherosclerosis, as well as mechanisms of action and pharmacokinetics of the most widely used antioxidant vitamins--E, C and beta-carotene, and the perspectives of their usage in cardio-vascular prophylaxy based upon the recent experience in antioxidant vitamin supplementation.