Age Affects Stem Cell Capacities

As we age, stem cells throughout our bodies gradually lose their capacity to repair damage, even from normal wear and tear. Michael Rudnicki, from the Ottawa Hospital Research Institute and University of Ottawa (Canada), and colleagues have found that as muscle stem cells age, their reduced function is a result of a progressive increase in the activation of a specific signalling pathway – the JAK/STAT signalling pathway, which normally transmits information to a cell from the surrounding tissue. With increased activity of the JAK/STAT pathway, fewer divide to produce two satellite cells and more commit to cells that eventually become muscle fiber. This reduces the population of these regenerating satellite cells, which results in a reduced capacity to repair and rebuild muscle tissue. The study authors submit that: “age-related intrinsic properties that functionally distinguish satellite cells and suggest a promising therapeutic avenue for the treatment of muscle-wasting diseases.”