A new study has shown how muscle stem cells protect themselves from loss in old age: as we age, muscles lose their ability to regenerate quickly, due to increased production of the protein NDRG1 in muscle stem cells. Prof Dr Julia von Maltzahn from the BTU Cottbus-Senftenberg, who has spent many years researching muscle regeneration during ageing as a group leader at the Leibniz Institute on Aging – Fritz Lipmann Institute (FLI), has published a commentary on this article, as these new findings will change the way we look at changes in stem cells during ageing.
Muscle stem cells are essential for repairing our skeletal muscles. In young people, they respond very quickly to injuries, dividing and helping to rapidly replace damaged muscle tissue. However, these cells change with age, and muscles regenerate much more slowly – this has been known for some time.
A study on “Cellular survivorship bias as a mechanistic driver of muscle stem cell aging” by Jengmin Kang et al. from Stanford University School of Medicine, USA, now published in the journal Science, reveals for the first time an important mechanism behind the changes in muscle stem cells during aging. In aging muscle stem cells in mice, the protein NDRG1 is produced in increased amounts, which slows down their activation after injuries but at the same time increases their survivability. This balance of delayed activity during regeneration and increased resistance explains a fundamental trade-off in the aging process of muscle regeneration – and provides a new cellular mechanism behind the observed loss of function of aging cells.
Prof Dr Julia von Maltzahn classifies the new findings by Kang et al. against the background of relevant work on changes in muscle stem cells associated with aging as follows.
“The study shows that muscle stem cells develop a kind of protective mechanism during the aging process that leads to the survival of a subpopulation of stem cells. It is therefore important to look at the aging process and not the final stage.”
Source: Leibniz Institute on Aging
