Help for a scarred heart: Scarring cells turned to beating muscle

ANN ARBOR-Poets and physicians know that a scarred heart cannot beat the way it used to, but the science of reprogramming cells offers hope-for the physical heart, at least. A team of University of Michigan biomedical engineers has turned cells common in scar tissue into colonies of beating heart cells. Their findings could advance the path toward regenerating tissue that's been damaged in a heart attack. Previous work in direct reprogramming, jumping straight from a cell type involved in scarring to heart muscle cells, has a low success rate. But Andrew Putnam, an associate professor of biomedical engineering and head of the Cell Signaling in Engineered Tissues Lab, thinks he knows at least one of the missing factors for better reprogramming. "Many reprogramming studies don't consider the environment that the cells are in-they don't consider anything other than the genes," he said. "The environment can dictate the expression of those genes." To explore how the cells' surroundings might improve the efficiency of reprogramming, Yen Peng Kong, a post-doctoral researcher in the lab, attempted to turn scarring cells, or fibroblasts, into heart muscle cells while growing them in gels of varying stiffness.