ABSTRACT
Thiols, ubiquitously distributed in aerobic cells, have been linked with a variety of key physiological functions (1,2). Disulfide linkages are critical determinants of protein structure. The cellular gutathione pool not only serves antioxidant functions but also serves as a reservoir of cysteine for protein synthesis. Fundamental physiological properties of cells such as growth and proliferation are also known to be regulated by cellular glutathione (1,2). The oxidation-reduction, or redox, states of protein-thiols are suggested to regulate a number of key signal transduction processes (3). Much of our current interest in thiols with respect to clinical disorders has stemmed from consistent observations that several pathophysiological conditions, such as certain forms of cancer and AIDS, are associated with lowered thiol status in some cells such as lymphocytes (4-7). Correction of such perturbations in cellular thiol homeostasis have resulted in beneficial clinical measures of outcome. Here the antioxidant and redox regulatory properties of the thiol-replenishing drug a-lipoic acid and discussed, highlighting the drug's remarkable therapeutic potential.
