Posted on 21 April 2020
As you get older can you stop your body from degrading? Can you stop your muscles from wasting away? The answer maybe yes. A recent study published in Nature Metabolism has reported that exercise can rejuvenate muscle stem cells in old mice, enhancing muscle repair.
The ability of skeletal muscle to repair itself declines with age. Dormant muscle stem cells are on standby to activate and repair tissue damage when required, but their function is reduced in older animals. In this study, researchers showed that exercise can restore this function. Older mice given access to a working running wheel had improved muscle repair ability after three weeks, while those that were unable to exercise saw no benefit. Young mice unsurprisingly had better muscle regeneration than the older mice, but experienced no further benefit from exercise.
The effect in old animals is very significant. We found that regular exercise restores youthfulness to tissue repair. Their muscle stem cells start to look and behave like those of much younger animals.Thomas Rando, MD, PhD, professor of neurology and neurological sciences and director of Stanford’s Glenn Center for the Biology of Aging
Exercise restores youthful properties to muscle stem cells of old mice in Stanford study. (1586). Retrieved 21 April 2020, from https://www.eurekalert.org/pub_releases/2020-04/sm-ery041020.php
Furthermore, researchers found that the exercise-induced rejuvenation hinged on the expression of cyclin D1, a signalling molecule that is is involved in maintaining muscle stem cell activation in response to damage. This raises the possibility that a drug mimicking the effects of cyclin D1 could one day be used to achieve similar regenerative effects without the need for exercise. Until then, exercise could be an effective intervention for the rejuvenation of old muscle stem cells, with the notable disclaimer that the results of this study might not hold true in humans.
Exercise is known to reduce the risk of a wide variety of age-related problems, including cardiovascular disease, cancer and perhaps even Alzheimer’s disease. There’s a lot of interest in understanding how exercise confers these health benefits.Thomas Rando, MD, PhD, professor of neurology and neurological sciences and director of Stanford’s Glenn Center for the Biology of Aging
It is also always worth pointing out that exercise has a vast range of benefits besides those studied here. Regardless of the significance of this study in humans or whether effects on stem cells could be replicated pharmacologically, exercise remains one of the most beneficial health interventions that an individual can make, irrespective of age.
Exercise rejuvenates quiescent skeletal muscle stem cells in old mice through restoration of Cyclin D1: https://doi.org/10.1038/s42255-020-0190-0
Exercise restores youthful properties to muscle stem cells of old mice in Stanford study: https://www.eurekalert.org/pub_releases/2020-04/sm-ery041020.php