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Frozen? Let it go to reset circadian rhythms
Robert F Harvey1, Anne E Willis1
1MRC Toxicology Unit, University of Cambridge, Cambridge, UK.
The EMBO Journal
|October 9, 2020
Summary
Hypothermia synchronizes the circadian clock by inducing nuclear accumulation of clock-repressing transcripts in human cardiomyocytes. Rewarming releases these transcripts, enabling clock protein synthesis and restoring circadian rhythm.
Area of Science:
- Cardiology
- Chronobiology
- Molecular Biology
Background:
- Research on severe hyperthermia's molecular events is limited, with prior studies focusing on cooling between 28°C and 35°C.
- The effects of profound hypothermia on cellular mechanisms remain largely unexplored.
Discussion:
- This study investigates human cardiomyocytes at significantly lower temperatures (8°C, 18°C, and 28°C).
- A novel hypothermia-induced mechanism synchronizing the circadian clock was identified.
Key Insights:
- Cooling human cardiomyocytes induces nuclear accumulation of transcripts encoding negative circadian clock regulators.
- Upon rewarming, these transcripts are released into the cytoplasm.
- This release facilitates the synthesis of specific clock proteins, thereby synchronizing the circadian clock.
Outlook:
- Further research can explore therapeutic applications of controlled hypothermia in circadian rhythm disorders.
- Investigating the precise molecular pathways involved in transcript release and protein synthesis is warranted.
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