Copper-Zinc and Manganese Superoxide Dismutase Activities in Cardiac and Skeletal Muscles during Aging in Male Rats

Abstract
The activities of total superoxide dismutase (SOD) and the manganese (Mn SOD) and copper-zinc (Cu-Zn SOD) forms were determined in the supernatant fraction of heart, liver and six skeletal muscles from rats during aging. Total SOD activity increased in most muscles between 3 and 23 months of age. There was no change in activity in liver between 3 and 19 months of age. The increase in total activity in heart was due to increased Mn SOD activity, whereas increases in skeletal muscles were due to Cu-Zn SOD or to both Cu-Zn and Mn SOD. The nutritional implications during aging are discussed.