Circadian disruption and muscle loss may create a self-reinforcing cycle

Circadian disruption and skeletal muscle wasting may create a bidirectional self-reinforcing loop in critical illness, shift work, and aging.

• Environmental disruption of the skeletal muscle clock may impair protein turnover and mitochondrial function, leading to muscle atrophy.
• Loss of muscle mass could weaken peripheral clock output, disrupting systemic circadian rhythms.
• Genetic evidence from global Bmal1 knockout models supports the idea that circadian disruption amplifies muscle wasting.
• Human sleep-deprivation studies provide additional support for the relationship between circadian rhythm disturbances and muscle health.
• Correlative evidence from clinical observations and disease models suggests that muscle wasting may also disrupt circadian rhythms.

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