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bioRxiv · 10.1101/2024.10.17.618893

Altered Proteasome Composition in Aging Brains, Genetic Proteasome Augmentation Mitigates Age-Related Cognitive Declines, and Acute Proteasome Agonist Treatment Rescues Age-Related Cognitive Deficits in Mice

Pickering, A.
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Abstract

The aging brain experiences a significant decline in proteasome function, The proteasome is critical for many key neuronal functions including neuronal plasticity, and memory formation/retention. Treatment with proteasome inhibitors impairs these processes. Our study reveals a marked reduction in 20S and 26S proteasome activities in aged mice brains driven by reduced functionality of aged proteasome. This is matched by a decline in 20S proteasome but an increase in 26S proteasome. Our data suggests this may be a compensatory response to reduced functionality. By overexpressing the proteasome subunit PSMB5 in the neurons of mice, enhancing proteasome function, we slowed age-related declines in spatial learning and memory as well neuromuscular declines. We then showed acute treatment with a proteasome activator to rescue spatial learning and memory deficits in aged mice. These findings highlight the potential of proteasome augmentation as a therapeutic strategy to mitigate age-related cognitive declines.

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Pickering, A.. 2024-10-20. Altered Proteasome Composition in Aging Brains, Genetic Proteasome Augmentation Mitigates Age-Related Cognitive Declines, and Acute Proteasome Agonist Treatment Rescues Age-Related Cognitive Deficits in Mice. https://doi.org/10.1101/2024.10.17.618893

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