Impaired proteostatic mechanisms other than decreased protein synthesis limit old skeletal muscle recovery after disuse atrophy.

ABSTRACT:

Background

Skeletal muscle mass and strength diminish during periods of disuse but recover upon return to weight bearing in healthy adults but are incomplete in old muscle. Efforts to improve muscle recovery in older individuals commonly aim at increasing myofibrillar protein synthesis via mammalian target of rapamycin (mTOR) stimulation despite evidence demonstrating that old muscle has chronically elevated levels of mammalian target of rapamycin complex 1 (mTORC1) activity. We hypothesized that protein synthesis is higher in old muscle than adult muscle, which contributes to a proteostatic stress that impairs recovery.

Methods

We unloaded hindlimbs of adult (10-month) and old (28-month) F344BN rats for 14 days to induce atrophy, followed by reloading up to 60 days with deu

SUBMITTER: Fuqua JD 

PROVIDER: S-EPMC10570113 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature