AGE-RELATED-CHANGES IN PLASMA-LIPID PEROXIDATION AND ANTIOXIDANT SYSTEM IN HUMANS AND RATS

This study was carried out on young (20-35 years) and old (60-85 years ) men and rats (6 vs 22 months) to investigate the effect of aging on plasma lipid peroxidation and the antioxidant system. Plasma polyunsat urated fatty acid (PUFA), total fatty acid (TFA) and malondialdehyde ( MDA) levels increased in aged humans and rats compared with young grou ps. However, plasma MDA/TFA ratios did not increase in aged humans and rats. Plasma vitamin E/TFA, and total thiol content were found to dec rease both in aged humans and rats. Plasma antioxidant activity (AOA) decreased only in aged rats. In addition, the susceptibility of VLDL LDL, apolipoprotein B containing lipoproteins to copper-induced perox idation increased with aging. It is concluded that aging is associated with some variations in plasma oxidant-antioxidant balance. (C) 1997 Elsevier Science Ireland Ltd.