Stem Cells Rejuvenate Muscle Post-Exercise

Forming part of the stroma, the connective tissue that supports organs and other tissues, and excreting growth factors, mesenchymal stem cells (MSCs) are shown to aid muscle repair and strengthening following resistance exercise, in a lab animal model. Marni D. Boppart, from the University of Illinois (Illinois, USA), and colleagues injected MSCs into mouse leg muscles prior to several bouts of eccentric exercise (similar to the lengthening contractions performed during resistance training in humans that result in mild muscle damage).  As a result, the rate of repair was increased and the growth and strength of those muscles was enhanced.  The study revealed that MSCs stimulate satellite cells – muscle precursor cells, to expand inside the tissue and contribute to repair following injury. Once present and activated, satellite cells fuse to the damaged muscle fibers and form new fibers to reconstruct the muscle and enhance strength. Writing that: “The results from this study demonstrate that [muscle mesenchymal stem cells] contribute to beneficial changes in satellite cell expansion and growth in [alpha]7Tg muscle following eccentric exercise,” the study authors submitthat: “[mesenchymal stem cells] that naturally accumulate in muscle following eccentric contractions may enhance the adaptive response to exercise.”