Oxidative stress induced in pathologies:: the role of antioxidants

Exposure to oxidant molecules issued from the environment (pollution, radiation), nutrition, or pathologies can generate reactive oxygen species (ROS for example, H2O2, O-2-, OH). These free radicals can alter DNA, proteins and/or membrane phopholipids. Depletion of intracellular antioxidants in acute oxidative stress or in various diseases increases intracellular ROS accumulation. This in turn is responsible for several chronic pathologies including cancer, neurodegenerative or cardiovascular pathologies. Thus, to prevent against cellular damages associated with oxidative stress it is important to balance the ratio of antioxidants to oxidants by supplementation or by cell induction of antioxidants. (C) 1999 Elsevier, Paris.