Food restriction enhances the proteolytic capacity of the aging rat liver

The effects of age and food restriction upon the proteolytic capacity of the liver of SPF Fischer 344 rats have been investigated. The proteolytic capacity of the perfused liver of ad libitum fed animals increased from 3 to 6 months of age and then declined linearly through 24 months of age. Food restriction had no effect at 3 months of age (6 weeks of food restriction), but by 6 months of age the proteolytic capacity was approximately 25% greater than that of the liver of ad libitum fed animals; this increment was increased through 24 months of age. Therefore, food restriction, while not preventing the age-related decline in protein degradation, did produce a greater proteolytic capacity at any age from 6 months on.