Evaluation of the possible contribution of antioxidants administration in metabolic syndrome.

The metabolic syndrome (MetS) is common, and its associated risk burdens of diabetes and cardiovascular disease (CVD) are a major public health problem. The hypothesis that main constituent parameters of the MetS share common pathophysiologic mechanisms provides a conceptual framework for the future research. Exercise and weight loss can prevent insulin resistance and reduce the risk of diseases associated with the MetS. Interrupting intracellular and extracellular reactive oxygen species (ROS) overproduction could also contribute to normalizing the activation of metabolic pathways leading to the onset of diabetes, endothelial dysfunction, and cardiovascular (CV) complications. On the other hand, it is difficult to counteract the development of CV complications by using conventional antioxidants. Indeed, interest has focused on strategies that enhance the removal of ROS using either antioxidants or drugs that enhance endogenous antioxidant defense. Although these strategies have been effective in laboratory experiments, several clinical trials have shown that they do not reduce CV events, and in some cases antioxidants have actually worsened the outcome. More research is needed in this field.