[Mechanisms of free radical oxidation and its role in aging].

The review covers enormous literature data arguing that oxidative stress is a reliable marker of aging. The role of mitochondrial and non-mitochondrial sources of free radical species in physiological aging and in pathogenesis of age-dependent diseases is discussed. The state of antioxidant systems of an organism in aging is described; special attention is paid to the studies of the interrelation between antioxidant enzyme activities and life expectancy, which becomes more apparent with transgenic animals. Data are presented on low molecular weight compounds that have antioxidant properties and serve their purpose as geroprotectors.