Old Muscle-Treated (image) University of California - Berkeley Caption Shown here is muscle tissue from an old mouse. After UC Berkeley researchers manipulated the biochemical response of adult stem cells in the old tissue, the muscle was able to repair itself from damage almost as well as muscle from young mice. Credit Photo courtesy of Morgan Carlson and Irina Conboy, UC Berkeley Usage Restrictions Use with credit to Morgan Carlson and Irina Conboy Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.