title: Mechanisms of biologic aging.
abstract: The authors outline the progression of thought on the mechanism of the aging process, giving emphasis to environmental factors that influence genetic events. Discussion is limited to those theories that explain fundamental causes of aging and have a firm thermodynamic basis. The authors propose that the cumulative result of continual oxidative stress and other thermodynamic processes (such as amino-acid racemization and nonenzymatic glycosylation), resulting in altered function and increasing the net entropy of living systems, governs the rate of the aging process.
mesh_terms: D000375:Aging; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D004734:Energy Metabolism; D005609:Free Radicals; D005786:Gene Expression Regulation; D005978:Glutathione / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D008136:Longevity; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D013482:Superoxide Dismutase / Q000378:metabolism; D013696:Temperature; D013816:Thermodynamics
chemical_list: D000596:Amino Acids; D000975:Antioxidants; D005609:Free Radicals; D002374:Catalase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005982:Glutathione Transferase; D005978:Glutathione