A new study conducted by a team of scientists led by Giles Duffield, assistant professor of biological sciences and a member of the Eck Institute for Global Health at the University of Notre Dame, focuses on the circadian clock of the heart, using cultured heart tissue. The results of the new study have implications for cardiovascular health, including daily changes in responses to stress and the effect of long-term rotational shift work.
Previous studies by a research group at the University of Geneva demonstrated a role for glucocorticoids in shifting the biological clock, and characterized this effect in the liver.
The new Notre Dame study, which appears in the Oct. 23 edition of the journal PLoS ONE, reveals that time-of-day specific treatment with a synthetic glucocorticoid, known as dexamethasone, could shift the circadian rhythms of atria samples, but the time-specific effect on the direction of the shifts was different from the liver. For example, when glucocorticoid treatment produces advances of the liver clock, in the atria it produces delays.