ABSTRACT
Aging is de ned as the progressive loss of function accompanied by decreased fertility and increased mortality with the advance of age (Kirkwood and Austad, 2000). In addition, it is said to be a common phenomenon to all multicelled organisms and has been described as an endogenous and a progressive decline in the effectiveness of physiological processes after the reproductive phase of life (Camougrand and Rigoulet, 2001; Barja, 2002; Sohal et al., 2002). The aforementioned decline has been attributed either to a genetic program present in all the individuals of a species or else to the stochastic accumulation of errors in the somatic cells, which would give rise to the progressive loss of cell functions (Camougrand and Rigoulet, 2001). The study of aging confronts, among others issues, the problem of separating the process itself from diseases related to aging.
