In a recent collaboration, a group of researchers has identified a physiological mechanism in mice that could maintain the regenerative capacity of muscle stem cells until geriatric age.

The regeneration of skeletal muscle depends on satellite cells in a dormant or quiescent state – a situation that can be triggered by either damage or stress to form new muscle fibers and expand in new stem cells. With aging, the regenerative capacity of these stem cells declines.

Within their study, which has been published in Nature Cell Biology, the investigators found that in mice, all muscle stem cells – despite being quiescent – are not equal. The team reported that they identified a subgroup of these cells that could maintain their regenerative capacity over time, declining only at geriatric age.

The researchers demonstrated that activation of the FoxO signaling pathway enabled this subgroup of quiescent stem cells to have a greater regenerative capacity. However, at geriatric age, activation of the FoxO pathway in this subgroup of cells is lost, resulting in a loss of functionality.

According to the results of the study, compounds that activate FoxO may have a rejuvenating effect on aged muscle stem cells. This opens up a way to improve the health of elderly people who are debilitated by the loss of muscle mass. Additionally, it may also be useful for individuals who have lost muscle mass due to neuromuscular diseases, effects associated with cancer, or infectious/inflammatory diseases.

“These findings reveal transcriptional determinants of stem-cell heterogeneity that resist aging more than previously anticipated and are only lost in extreme old age, with implications for the repair of geriatric muscle,” the researchers stated within their study.

Link: https://www.regmednet.com/muscle-stem-cells-could-retain-high-regenerative-capacity-until-geriatric-age-study-reveals/