REACTIVE OXYGEN SPECIES AND ANTIOXIDANTS IN SIGNAL-TRANSDUCTION AND GENE-EXPRESSION

Reactive oxygen species (ROS) are produced by cellular metabolic react ions, and have been implicated in the pathogenesis of several diseases , including atherosclerosis, cancer, and Alzheimer's disease. interest ingly clinical and epidemiologic studies have, in some cases, indicate d that antioxidant nutrients may be effective in disease prevention. H owever, the efficacy of specific antioxidants in disease prevention is often both controversial and inconclusive. In an effort to elucidate the role of ROS and antioxidants in disease development and prevention , the chemistries of ROS and antioxidants have been examined extensive ly. Recently, molecular and cellular approaches have demonstrated that ROS and antioxidants can directly affect the cellular signaling appar atus and, consequently, the control of gene expression. This new resea rch provides the link between ROS and antioxidant chemistries and the mechanisms of disease processes and prevention. This review illustrate s how ROS function as potential intracellular and extracellular signal ing molecules and how antioxidants can affect this process.