Animal study · Exercise · 18 Oct 2026
In flies and aging mice, exercise lowered DEAF1 and rebalanced a growth signal tied to muscle repair
Source: Duke-NUS / PNAS
What the research found
Study (fruit flies and mice). Sze Mun Choy, Hong-Wen Tang, and colleagues at Duke-NUS Medical School, with Singapore General Hospital and Cardiff University, report in PNAS (24 Nov 2025; DOI 10.1073/pnas.2508893122). Science outlets recirculated the paper on 15 Oct 2026. DEAF1 rose in aging muscle, increased mTOR transcription, and left the growth complex mTORC1 overactive, with worse turnover of damaged proteins. Exercise lowered Deaf1 through FOXO. Blocking FOXO, or forcing DEAF1 higher, blocked those exercise effects in the animals. Raising DEAF1 weakened muscle; lowering it improved the balance of building and cleanup. This is not a human treatment and does not prove the same switch explains muscle loss in people. Not medical advice.
Evidence level: Animal study. Results in animals or cells often don't carry over to people.
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