Ageing and apoptosis.

Ageing is accompanied by a general decline of physiological function, especially at later stages, and significant increases in the incidence of cancer and other degenerative diseases. It has recently been hypothesized that alterations in apoptosis may contribute to these age-associated changes. However, whether there is a role for apoptosis in the ageing process and how ageing may modify the regulatory machinery of apoptosis remains obscure. Although the literature addressing these issues is scarce, research in this area is gaining momentum. Molecules involved in apoptosis signaling in mammals have been found to regulate ageing in organisms such as Caenorhabditis elegans and Drosophila melanogaster. Caloric restriction studies in a wide variety of organisms, ranging from yeast to mammals, suggest the conserved nature of the ageing regulatory systems. It seems very likely that signals that regulate ageing will impact apoptosis and the extent of apoptosis may then impact ageing. However, to date, there has been no direct evidence supporting the existence of such cross-communication between ageing and apoptosis in mammalian system. Here we review progress in the field.