Age-related Changes in the Mitochondrial Superoxide Production by Peripheral Phagocytes in Whole Blood

PURPOSE: Ageing is a complex multi-factorial process. There are data published on reactive oxygen species (ROS) and oxidative stress as the factors that determine the lifespan of organisms. The oxidative injury of mitochondrial enzymes and the mitochondrial genome itself have been considered to play a role in a number of age-related degenerative processes. The aim of the present work was to study the changes that occur with age in the mitochondrial superoxide production by zymosan-stimulated phagocytes in whole blood. METHODS: Forty normal adult subjects having age range 40-70 years were included in the study. The mitochondrial superoxide production by peripheral phagocytes was evaluated by lucigenin chemiluminescence (LgCL). RESULTS: It was found that the velocity of phagocyte activation assessed as the reciprocal of the time to the peak of LgCL kinetic curve decreased with age. The maximum oxidative activity and the total oxidative capacity of the cells initially increased and then remained unchanged after the age of 50 years. CONCLUSION: We believe it is time now to revise the mitochondrial theory of ageing and to answer the question of whether ROS are just a peripheral target correlating with longevity or central regulators of the ageing process.