Circadian rhythms and cardiac physiology: An essential interplay

Area of Science:

• Cardiovascular Biology
• Chronobiology
• Molecular Cardiology

Background:

• Circadian clocks regulate essential functions in nearly all human cells, including the heart.
• Disruptions to clock genes significantly impact cardiac physiology.
• Cardiac cells exhibit distinct circadian rhythms influencing tissue-specific functions.

Purpose of the Study:

• To review the effects of clock gene manipulation on cardiac function.
• To summarize current knowledge of circadian clocks in various cardiac cell types.
• To highlight knowledge gaps in non-cardiomyocyte cardiac clock function.

Main Methods:

• Literature review of studies on clock gene manipulation (whole body and cardiomyocyte-specific).
• Synthesis of existing research on circadian clock mechanisms in cardiomyocytes, endothelial cells, fibroblasts, and immune cells.
• Identification of mechanistic links between core clock components and cardiac-specific genes.

Main Results:

• Clock gene disruption impacts multiple aspects of cardiac physiology.
• Mechanistic links are established between core clock components and cardiomyocyte-specific genes.
• Circadian clock function in non-cardiomyocyte cardiac cells (endothelial, fibroblasts, immune) is poorly understood.

Conclusions:

• Further research is needed to understand temporal segregation of clock processes in cardiac non-cardiomyocytes.
• Clock-controlled mechanisms in cardiac cells represent potential targets for chronotherapy.
• Optimizing cardiovascular disease treatments may be achieved through chronotherapy targeting cardiac clock mechanisms.