Can We Reverse Age-Related Loss of Muscle Mass?

We've all seen it, in our patients and in ourselves: As we grow older, we lose muscle mass and restoring that mass with exercise gets more difficult. In mammals, muscle contains tissue-specific adult stem cells (called satellite cells) that are recruited to produce new myocytes in response to muscle damage or stress. For some reason, these satellite cells become less vigorous with age.

A team from Spain studied this phenomenon in mice. The investigators confirmed that, in older mice, satellite cells are less able to accomplish the two things muscle stem cells need to do: reproduce and differentiate into muscle tissue. Instead, the satellite cells entered senescence. The investigators compared the gene expression profiles of satellite cells i…