From life to death--the struggle between chemistry and biology during aging: the Maillard reaction as an amplifier of genomic damage.

Abstract

Biogerontology is the study of the aging of biological systems. This review addresses the relationship between chemistry and biology during aging, proposing that chemistry is responsible for the aging of biological systems. In the continuing struggle between chemistry and biology, chemistry is always the short-term, tactical winner--death of the individual is inevitable. However, barring the extinction of species, biology is the long-term, strategic victor--life survives, and the struggle continues. The rate of random chemical damage to the genome is considered the major factor determining lifespan of species. Oxidative stress and reactive oxygen species are recognized as a primary source of damage in aging and chronic disease. The Maillard reaction, involving nonenzymatic, oxidative reactions of carbohydrate and lipid substrates, is seen as an amplifier of reactive oxygen damage. Maillard reaction products in protein are viewed as integrators of cumulative damage by reactive oxygen, and possibly as initiators of protective responses, but the primary factor affecting lifespan is identified as silent cumulative damage to the genome, resulting from imperfect repair. Maillard reaction inhibitors show promise for treatment of chronic diseases, such as diabetes and atherosclerosis, and also have a positive effect on health in normal animals. Future studies should focus on evaluation of the effects of these inhibitors on genomic damage and lifespan extension.