Vitamins E and C for prevention of cardiovascular disease.

Oxidative stress seems to play a key-role in the pathogenesis of atherosclerosis. Agents that prevent LDL from oxidation have been shown to reduce initiation of atherosclerosis. Among these, the antioxidant micronutrients, including the carotenoids and vitamins C and E, have gained wide interest because of the potential for prevention of atherosclerotic vascular disease in humans. Lipid-soluble antioxidants present in LDL, including á-tocopherol (vitamin E), and water-soluble antioxidants present in the extracellular fluid, including ascorbic acid (vitamin C), inhibit LDL oxidation through an LDL-specific antioxidant action. Moreover antioxidants present in the cells of the vascular wall decrease cellular production and release of reactive oxygen species (ROS), inhibit endothelial activation (expression of adhesion molecules and monocyte chemoattractants), and improve the biologic activity of endothelium-derived nitric oxide (EDNO) through a cell- or tissue-specific antioxidant action. In the last decade many trials with antioxidants have been planned in patients with cardiovascular disease but the results are equivocal. The reason for the disappointing findings is unclear but one possible explanation is the lack of identification criteria of patients who are potentially candidates for antioxidant treatment. Several studies have been done in patients at risk of cardiovascular disease indicating that enhanced oxidative stress is associated with the presence of the classical risk factors for atherosclerosis, like diabetes, hypercholesterolemia, hypertension, smoking and obesity. In this chapter the data so far reported will be analyzed to see if there is a clear support the hypothesis that patients at risk of cardiovascular may be candidates for antioxidant treatment.