Boosting Immune Function Could Assist in Muscle Regeneration

A new study published in the scientific journal Nature Aging has revealed a new way to modulate immune cell function to restore regenerative abilities in the muscle of aged mice. The study shows that the immune system plays a key role in muscle regeneration, and as our organisms age, the muscles lose the capacity to regenerate.

The researchers found a protein called MANF that regulates the function of macrophages, a type of immune cell capable of phagocytosis, ingesting and eliminating particles inside cells. However, macrophages in aged mice have reduced levels of MANF, which impairs their ability to regenerate muscle. 

Increasing the levels of MANF in aged muscle is sufficient to recover the muscle’s regenerative capacity. This finding could be used in the future to promote the reparative function of the immune system and improve the success of current stem-cell-based therapies for muscle regeneration.

Pedro Sousa-Victor, co-leader of the study and a group leader at iMM, believes that MANF could be used as a supplement to improve the efficiency of current muscle regenerative therapies. The clinical success of current stem-cell-based therapies is limited by the capacity of aged and diseased organs to regenerate. Immune aging is an important obstacle to the regenerative capacity of aged muscle.

Age-related decline in skeletal muscle regenerative capacity is multifactorial, yet the contribution of immune dysfunction to regenerative failure is unknown. Macrophages are essential for effective debris clearance and muscle stem cell activity during muscle regeneration, but the regulatory mechanisms governing macrophage function during muscle repair are largely unexplored.

Restoring MANF levels is a viable strategy to improve myeloid response and regenerative capacity in aged muscle. These findings could be key to repairing aged or diseased muscles using stem cells and improving human health by delaying age-related diseases.