ABSTRACT

The study of free radical-mediated signaling processes in aging and senescence is a relatively new eld of current investigations. Attention was drawn worldwide to the role of free radicals in aging and senescence in 1956 by Dr. Harman’s work “Aging: A Theory Based on Free Radical and Radiation Chemistry” [1]. At that time the structures of free radicals, which are formed in cells and tissues, were unknown, and all free radicals were considered toxic species capable of destroying biomolecules and stimulating aging of living organisms. This hypothesis led to important practical conclusions, pointing out for the rst time the possibility of age regulation by antioxidants capable of suppressing free-radical formation.