Circadian Rhythm In Heart Cells Impacts Their Daily Function

Nov, 2021 - By WMR

A new study revealed the internal clock of heart cell that helps the heart turn its activity up and down in a 24-hour cycle.

Researchers found a different circadian mechanism in heart cells that affects cardiac activity shifts over a 24-hour period. The study published in the journal Nature Communication on October 15, 2021 offers clues about how shift workers are at greater risk of heart issues. According to the study, every heart cell contains a clock that controls frequency of firing rate through night and day, which helps the heart to beat rapidly during the day and to endure daily functions.

Human body works on a 24-hour cycle program of circadian rhythm, which influences other activities such as immune system activity as well as gene expression apart from sleeping and waking up. When this circadian rhythm is disrupted, it causes heart diseases and cancer incidences. This new study revealed an unknown mechanism in heart cells that affects heart functions during the day. According to the study sodium and potassium ion levels in heart cells drop throughout the day and rise in the night. These were significant fluctuations with 30 % drop of ion levels during the day. Due to these alterations heart rate activity changes, which is a new circadian mechanism that scientists discovered.

The study explains many of the heart related fatal problems occur at particular times of the day, and mostly in shift workers. According to the scientists, when the circadian clock in the heart and brain are desynchronised, as throughout the shift work, cardiovascular systems may become weak to handle the daily stresses of working life making the heart more vulnerable to dysfunction. Moreover, this mechanism could also play a role in age-related heart diseases. From the findings of this study it is hypothesized that age-related dysfunction in this circadian clock in heart cells could also reduce the responding ability of the heart in day time activity.