Age-dependent Changes of Proteasome Activities in Ts65Dn Down`s Syndrome model mice

Abstract

Segmental trisomy 16, Ts65Dn mice is a model of human trisomy 21 (Down`s syndrome; DS) and also mimics some aspects of Alzheimer`s disease (AD). We determined proteasome activities in the hippocampus of Ts65Dn mice at the various ages. Ts65Dn mice did not show significant differences compared to F1, parental strain control mice and LM, littermate normosomic control mice, at 1-2 months of age. All experimental groups, Ts65Dn, F1, LM mice, showed age-dependent increase of proteasome activity by 12 months of age. However, only Ts65Dn mice showed significant increase of proteasome activity at 4 months of age compared to 1-2 months of age. These results indicate that the increased proteasome activities are potentially related to aging associated biochemical events in the process of the cognitive deficits, which are found in AD or DS.