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Published on: January 24, 2013
A brief history of circadian time in the heart
Martin E Young1, Vanya Khanna2, Mallory Metcalfe2
1Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
Insights
Circadian rhythms significantly impact cardiovascular health, influencing everything from heart function to disease outcomes. Understanding these daily biological rhythms offers new pathways for improving heart health and disease treatment.
Area of Science:
- Cardiovascular Science
- Chronobiology
- Molecular Medicine
Background:
- Early clinical observations noted daily variations in heart rate, blood pressure, and cardiovascular events.
- Recent decades have uncovered the mechanisms and clinical applications of these biological rhythms.
- The heart possesses intrinsic circadian properties influencing numerous physiological processes.
Purpose of the Study:
- To review the discovery and impact of circadian biology in cardiovascular science.
- To explore emerging themes and future frontiers in circadian cardiovascular medicine.
- To provide a roadmap for harnessing circadian rhythms to improve cardiovascular health.
Main Methods:
- Review of historical clinical observations.
- Analysis of recent research on molecular and physiological mechanisms.
- Synthesis of emerging themes and future research directions.
Main Results:
- Circadian rhythms regulate cardiac gene/protein expression, metabolism, and electrophysiology.
- Circadian timing affects ischemic injury, cardiac aging, and disease synchrony.
- Circadian medicine is reshaping clinical care, including chronotherapies and drug development.
Conclusions:
- Circadian biology offers a powerful framework for understanding and treating cardiovascular disease.
- Harnessing circadian rhythms can lead to improved cardiovascular health outcomes.
- Future research in epigenetics, gene editing, and spaceflight will further advance circadian cardiovascular medicine.
Abstract:
This review tracks the discovery of circadian biology in cardiovascular science, starting with early clinical observations of daily changes in heart rate, blood pressure, and cardiovascular events. These patterns suggested that time of day matters, but it was not until the past two decades that the mechanisms and knowledge translation of these rhythms were uncovered. We describe the heart's intrinsic circadian properties and importantly how this leads to regulation of cardiac gene and protein expression, neuroendocrine and vascular rhythms, metabolism, cellular electrophysiology, and cell signaling pathways. Next, we explore emerging themes, including the impact of circadian timing on ischemic injury, cardiac aging, and trends in circadian desynchrony, sex, and interorgan crosstalk. Building on these discoveries, circadian medicine is beginning to reshape clinical care including timing of surgery, chronotherapies, biomarkers, ICU design, novel molecular drugs targeting the circadian clock, the role of the microbiome and time restricted eating, the new field of rest, and the concept of One Health and applications to veterinary medicine. Looking ahead we address new frontiers such as epigenetics, gene editing, and spaceflight. Together, these advances offer a roadmap for how circadian rhythms can be harnessed to improve cardiovascular health and disease outcomes, supporting longer and healthier lives.
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