The evolutionary theories of aging revisited--a mini-review

Abstract

This short review portrays the evolutionary theories of aging in the light of the existing discoveries from genomic and molecular genetic studies on aging and longevity. At the outset, an historical background for the development of the evolutionary theories of aging is presented through the works of August Weismann (programmed death and the germ plasm theories) including his exceptional theoretical postulation, later experimentally validated by the existence of cell division limits. Afterwards, the theory of mutation accumulation of Peter Medawar and the theory modification by Charlesworth (late-life mortality plateau) are presented as well as the antagonistic pleiotropy hypothesis of George Williams, and the disposable soma theory of Kirkwood and Holliday. These theories are discussed in the light of the different research studies, which include studies on insulin signaling and longevity, the possibility that nuclear factor kappa B may be a major mediator of aging, studies of anti-aging Sirtuins and studies on heat shock proteins and longevity and on gene sets as biomarkers of aging. Finally, the proposals for future research in biogerontology, such as studies on the control of protein synthesis, validation of biomarkers of aging, understanding the biochemistry of longevity and research in the field of gerontologic pathology are presented. Likewise, further attention is suggested regarding the work on telomere shortening, stem cells and studies on understanding the biochemical and molecular basis for longevity in centenarians.