AGE-RELATED LOSSES OF COGNITIVE FUNCTION AND MOTOR-SKILLS IN MICE AREASSOCIATED WITH OXIDATIVE PROTEIN DAMAGE IN THE BRAIN

The hypothesis that age-associated impairment of cognitive and motor f unctions is due to oxidative molecular damage was tested in the mouse. In a blind study, senescent mice (aged 22 months) were subjected to a battery of behavioral tests for motor and cognitive functions and sub sequently assayed for oxidative molecular damage as assessed by protei n carbonyl concentration in different regions of the brain. The degree of age-related impairment in each mouse was determined by comparison to a reference group of young mice (aged 4 months) tested concurrently on the behavioral battery. The age-related loss of ability to perform a spatial swim maze task was found to be positively correlated with o xidative molecular damage in the cerebral cortex, whereas age-related loss of motor coordination was correlated with oxidative molecular dam age within the cerebellum. These results support the view that oxidati ve stress is a causal factor in brain senescence. Furthermore, the fin dings suggest that age-related declines of cognitive and motor perform ance progress independently, and involve oxidative molecular damage wi thin different regions of the brain.