Stem cells need recovery time, too
Researchers’ strategy may help rejuvenate aging muscle tissue
Is aging inevitable? What factors make older tissues in the human body less able to maintain and repair themselves, as in the weakening and shrinkage of aging muscles in humans? A new study from Harvard-affiliated Massachusetts General Hospital (MGH) investigators and collaborators at Kings College London describes the mechanism behind impaired muscle repair during aging and a strategy that may help rejuvenate aging tissue by manipulating the environment in which muscle stem cells reside.
Rare muscle stem cells are located inside each skeletal muscle of the body. Also called satellite cells, because of their position on the surface of the muscle fibers they serve and protect, these cells are essential to maintaining the capacity of muscles to regenerate. Satellite cells are able to generate new, differentiated muscle cells while keeping their identity as stem cells, retaining the ability to maintain and repair muscle tissue. Normally in a resting or dormant state, satellite cells respond rapidly to repair injured tissues. The current study finds that aging muscle stem cells lose their ability to maintain a dormant state, so that when called upon to repair injured muscle, they are unable to mount an adequate response.