Cellular redox regulation and prooxidant signaling systems: a new perspective on the free radical theory of aging.

The overarching role of coenzyme Q(10) in gene regulation, bioenergy formation, cellular redox poise regulation, and hydrogen peroxide formation is presented. Coenzyme Q(10) has a central role acting as a prooxidant in the generation of H(2)O(2). Contrary to the dogma that superoxide and H(2)O(2) formation are highly deleterious to cell survival this premise is rejected. Data are discussed that continuous superoxide and hydrogen peroxide formation are essential for normal cell function and that they play a major role in subcellular redox state modulation. It is the prooxidant activity of the so-called antioxidants that may be responsible for previously claimed benefits for high doses of oxido-reduction nutritional supplements such as alpha lipoic acid and coenzyme Q(10). Oxygen-free radical formation is essential for the biological function and is not a direct causation of the mammalian aging process; aging is a multisystem stochastic process.