Reactive oxygen species and age-related genes p66Shc, sirtuin, FoxO3 and klotho in senescence

Reactive oxygen species (ROS) superoxide and hydrogen peroxide perform important signaling functions in many physiological and pathophysiological processes. Cell senescence and organismal age are not exemptions. Aging-regulating genes p66shc, Sirtuin, FOXO3a and Klotho are new important factors which are stimulated by ROS signaling. It has been shown that ROS participate in initiation and prolongation of gene-dependent aging development. ROS also participate in the activation of protein kinases Akt/PKB and extracellular signal-regulated kinase ERK, which by themselves or through gene activation stimulates or retards cell senescence. Different retarding/stimulating effects of ROS might depend on the nature of signaling species-superoxide or hydrogen peroxide. Importance of radical anion superoxide as a signaling molecule with "super-nucleophilic" properties points to the possibility of the use of superoxide scavengers (SOD mimetics, ubiquinones and flavonoids) for retarding the development of aging.