Aging-Related Changes in Proteasomal Activity and Activity of Neutral Proteinases in Brain Tissues of the Rats

摘要

We compared the proteasomal activity and activity of neutral proteinases in tissues of the neocortex and cerebellum in old (18 months) and young mature (5 months) rats. We found that, in homogenates of the tissues obtained from brains of old animals, the chymotrypsin-like activity of the proteasome complex in the cortex increased by 50% as compared with the control, while in the cerebellum such an activity remained practically unchanged. Peptidylglutamyl peptide hydrolase proteasomal activity increased on average by 72% in the cortex and by 14% in the cerebellum. Protamine-splitting activity, which is indicative of the activity of neutral proteinases, dropped insignificantly in the cortex and cerebellum (by 16.4 and 15.3%, respectively). The data obtained allow us to suppose that aging-related changes in brain cells result from disturbances of the functional connections between lysosomal and proteasomal proteolysis.