Circadian Clock Regulates Muscle Stem Cell Regeneration Through Coordinated Notch and Wnt Signaling
Researchers have identified the circadian clock as a master temporal regulator of skeletal muscle regeneration, coordinating the sequential activation of Notch and Wnt signaling in muscle stem cells. The study, published on bioRxiv, shows that clock activity marks cycling myogenic progenitor cells and that pharmacological stimulation of the clock enhances both proliferation and differentiation during repair. These findings open potential therapeutic avenues for muscle injuries and diseases such as muscular dystrophy.
A new preprint study on bioRxiv demonstrates that the circadian clock plays a central role in orchestrating skeletal muscle regeneration by temporally coordinating two critical signaling pathways — Notch and Wnt — in muscle stem cells known as satellite cells. The researchers found that circadian clock activity specifically marks a cycling population of regeneration-activated myogenic progenitors, and identified key Notch pathway components as direct targets of the circadian clock. Genetic activation of the clock in satellite cells, as well as treatment with pharmacological clock-stimulating compounds, boosted both the proliferative expansion and subsequent differentiation of muscle progenitor cells. Crucially, these clock-dependent mechanisms remained functional in dystrophin-deficient mouse muscle and human myoblasts derived from muscular dystrophy patients, suggesting broad relevance. Clock-activating compounds also improved regeneration following acute muscle injury and in dystrophic muscle models. The findings reframe the circadian clock not merely as a timekeeper but as an active regulator of tissue repair signaling programs, with implications for chronobiology-informed therapies.
What's missing
As a preprint, this study has not yet undergone formal peer review, and independent replication has not been reported. The study does not fully address whether circadian disruption (e.g., shift work or sleep disorders) impairs muscle regeneration in humans, nor does it clarify optimal timing windows for pharmacological clock stimulation in a clinical context. Long-term safety and efficacy of clock-activating compounds in dystrophic models remain uncharacterized.
What different sources said
- bioRxivCenter
Circadian Clock Control of Muscle Stem Cells Through Temporal Coordination of Notch and Wnt Signaling
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