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bioRxiv · 10.1101/2022.03.07.482891

Skeletal Muscle Proteostasis Promotes Central Nervous System Rejuvenation and Reduces Neuroinflammation during Aging and Neurodegenerative Disease

Abstract

Skeletal muscle has recently arisen as a novel regulator of Central Nervous System (CNS) function and aging, secreting bioactive molecules known as myokines with metabolism-modifying functions in targeted tissues, including the CNS. Here we report the generation of a novel transgenic mouse with enhanced skeletal muscle lysosomal and mitochondrial function via targeted overexpression of Transcription Factor E-B (TFEB). We have discovered that the resulting geroprotective effects in skeletal muscle reduce neuroinflammation and the accumulation of tau-associated pathological hallmarks in a mouse model of tau pathology. Muscle-specific TFEB overexpression also significantly ameliorates proteotoxicity, reduces neuroinflammation and promotes transcriptional remodeling of the aged CNS, preserving cognition and memory in aged mice. Our results implicate the maintenance of skeletal muscle function throughout aging to direct regulation of CNS health and disease, and suggest that skeletal-muscle originating factors may act as novel therapeutic targets against age-associated neurodegenerative disorders.

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BibTeXRIS

Matthews, I., Birnbaum, A., Gromova, A., Coutinho, K., McGraw, M., Patterson, D., Banks, M. T., Nobles, A., Miranda, H. C., La Spada, A. R., Cortes, C. J.. 2022-03-08. Skeletal Muscle Proteostasis Promotes Central Nervous System Rejuvenation and Reduces Neuroinflammation during Aging and Neurodegenerative Disease. https://doi.org/10.1101/2022.03.07.482891

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