Researchers at the Sanford-Burnham Medical Research Institute (Sanford-Burnham) in La Jolla, California have developed a novel technique to promote tissue repair in damaged muscles. The technique also creates a sustainable pool of muscle stem cells (image) needed to support multiple rounds of muscle repair. The study, published onine on September 7, 2014 in Nature Medicine, provides promise for a new therapeutic approach to treating the millions of people suffering from muscle diseases, including those with muscular dystrophies and muscle wasting associated with cancer and aging. There are two important processes that need to happen to maintain skeletal-muscle health. First, when muscle is damaged by injury or degenerative disease such as muscular dystrophy, muscle stem cells—or satellite cells—need to differentiate into mature muscle cells to repair injured muscles. Second, the pool of satellite cells needs to be replenished so there is a supply to repair muscle in case of future injuries. In the case of muscular dystrophy, the chronic cycles of muscle regeneration and degeneration that involve satellite-cell activation exhaust the muscle stem-cell pool to the point of no return. "Our study found that by introducing an inhibitor of the STAT3 protein in repeated cycles, we could alternately replenish the pool of satellite cells and promote their differentiation into muscle fibers," said Alessandra Sacco, Ph.D., Assistant Professor in the Development, Aging, and Regeneration Program at Sanford-Burnham. "Our results are important because the process works in mice and in human muscle cells.Login Or Register To Read Full Story