Research
Hormonal
Muscle atrophy is driven by the hyperactivation of the ubiquitin-proteasome and autophagy-lysosome pathways, regulated by transcription factors like FoxO and NF-kB, leading to the upregulation of 'atrogenes' such as MuRF1 and MAFbx.
Muscle loss is driven by specific degradation pathways (proteasome, autophagy) regulated by transcription factors (FoxO, NF-kB). Preventing atrophy involves modulating these pathways, not just 'eating more'.
StrongSupportsVERY_HIGH confidence
Two major protein degradation pathways, the proteasomal and the autophagic–lysosomal pathways, are activated during muscle atrophy and variably contribute to the loss of muscle mass. These pathways involve a variety of atrophy-related genes or atrogenes, which are controlled by specific transcription factors, such as FoxO3... and NF-kB
Why this rating
Supported by knockout mouse models and extensive molecular biology studies.
Source
Mechanisms regulating skeletal muscle growth and atrophy
Stefano Schiaffino et al. · FEBS Journal · 2013
DOI 10.1111/febs.12253
narrative_reviewCited 1,484×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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