Induced cardiac pacemaker cells survive metabolic stress owing to their low metabolic demand

Abstract

Heart health: understanding pacemaker cells The heart’s pacemaker cells contain mitochondria that are smaller than average and require less energy than other heart cells, properties that help make them naturally resilient to stress. Cardiac pacemaker cells constitute a tiny proportion of the heart’s cells, yet play a critical role in maintaining a steady heartbeat. However, quite how pacemaker cells maintain their automatic rhythm is unclear because their scarcity makes them difficult to study. To examine the cells’ metabolic state further, Hee Cheol Cho at Emory University, Atlanta, and Brian Foster at Johns Hopkins University School of Medicine, Baltimore, and co-workers therefore induced pacemaker cells by adding an embryonic protein to heart muscle cells. The induced pacemaker cells survived well under oxidative stress. The team identified a protein in the pacemakers’ mitochondrial membranes, the expression of which directly influences rhythm responses.