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Circadian Clocks, Sleep, and Metabolism
Nora Nowak1,2, Audrey Rawleigh2, Steven A Brown3
1ETH Zurich, Department of Chemistry and Applied Biosciences, Zurich, Switzerland.
Advances in Experimental Medicine and Biology
|November 13, 2021
Summary
The body has a molecular circadian clock in most cells, regulating metabolism and sleep-wake cycles. This system works with brain circuits, suggesting a flexible metabolic control for activity and environment.
Area of Science:
- Physiology
- Chronobiology
- Metabolism
Background:
- A molecular circadian clock is present in the brain and most body cells.
- This clock governs daily metabolic rhythms and consolidates sleep-wake behavior into activity/feeding and sleep/fasting periods.
Purpose of the Study:
- To explore the interplay between the molecular circadian clock and brain regulatory circuits in controlling metabolism and sleep-wake states.
- To understand how these systems provide a flexible and redundant mechanism for metabolic adaptation.
Main Methods:
- Review of existing research on molecular circadian clocks.
- Analysis of evidence linking hypothalamic control of appetite and metabolism with sleep-wake regulation.
Main Results:
- Circadian clocks in peripheral tissues and the brain regulate daily metabolic rhythms.
- Sleep-wake states are primarily controlled by brain circuits, but may share regulatory centers with appetite control.
- Hypothalamic regulation of appetite and metabolism appears linked to sleep-wake control.
Conclusions:
- Circadian control of metabolism is overlaid by sleep-wake control, creating a dual system.
- This integrated system allows for flexible and redundant metabolic adjustments based on activity and environmental cues.
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