The network and the remodeling theories of aging: historical background and new perspectives

Two general theories, i.e. "the network theory of aging" (1989) and "the re modeling theory of aging" (1995), as well as their implications, new develo pments, and perspectives are reviewed and discussed. Particular attention h as been paid to illustrate: (i) how the network theory of aging fits with r ecent data on aging and longevity in unicellular organisms (yeast), multice llular organisms (worms), and mammals (mice and humans); (ii) the evolution ary and experimental basis of the remodeling theory of aging (immunological , genetic, and metabolic data in healthy centenarians, and studies on the e volution of the immune response, stress and inflammation) and its recent de velopment (the concepts of "immunological space" and "inflamm-aging"); (iii ) the profound relationship between these two theories and the data which s uggest that aging and longevity are related, in a complex way, to the capab ility to cope with a variety of stressors. (C) 2000 Elsevier Science Inc. A ll rights reserved.