Dietary restriction initiated late in life can reduce mitochondrial protein carbonyls in rat livers: Western blot studies

Life long dietary restriction has a variety of beneficial effects such as retarding the age-related decline of physiological functions as well as the onset of diseases, thus prolonging the life span of experimental animals. In the present work we investigated the effect of DR initiated late in life on rats regarding oxidative modifications of liver mitochondrial proteins in terms of generation of carbonyl moieties by western blot using antibodies against dinitrophenylhydrazones after the reaction of the proteins with dinitrophenylhydrazine. Protein carbonyls in mitochondria of 30-month-old animals increased by about 55% as compared with their 10-month-old counterparts. Every-other-day feeding initiated at the age of 26.5 months and continued for 3.5 months resulted in the decrease of the carbonyls to the level of the ad libitum fed young animals. Our findings suggest that DR initiated late in life can have a beneficial effect by reducing the accumulated oxidative damage in mitochondrial proteins.