A naturally occurring micronutrient, synthesized in small amounts by plants and animals (including humans), with antioxidant and potential chemopreventive activities. Alpha-lipoic acid acts as a free radical scavenger and assists in repairing oxidative damage and regenerates endogenous antioxidants, including vitamins C and E and glutathione. This agent also promotes glutathione synthesis. In addition, alpha-lipoic acid exerts metal chelating capacities and functions as a cofactor in various mitochondrial enzyme complexes involved in the decarboxylation of alpha-keto acids. Check for active clinical trials using this agent. (NCI Thesaurus)