Muscle injuries recover thanks to the action of the immune system in collaboration with stem cells. A study carried out by researchers at the Ottawa Hospital and the University of Ottawa (USA) has discovered how the interaction between the two works to eliminate dead tissue and then make way for new muscle fibers.
Apparently, according to the results published in the journal Science, hyaluronic acid, a natural substance that is in the body and is often used as an extra ingredient in cosmetic products, aesthetic injections and to treat osteoarthritis, could be the molecule key that controls this interaction.
“When muscles are damaged, it is important that immune cells quickly enter the tissue and remove the damage before stem cells start to repair themselves. Our study shows that muscle stem cells are primed to start repairing themselves right away, but immune cells keep the stem cells in a resting state while they finish the cleanup job. After about 40 hours, once the cleaning job is done, an internal alarm goes off in the muscle stem cells allowing them to wake up and start repairing themselves,” explains Dr. Jeffrey Dilworth, lead author of the study.
Improve the production of hyaluronic acid in older adults
The results of the research indicated that hyaluronic acid was key in the internal activation that tells the stem cells when to start working. In this way, when some type of muscle damage occurs, the stem cells begin to generate hyaluronic acid and cover themselves with it and, when the layer is thick enough, it blocks the sleep signal of the immune cells and causes the cells to wake up. mother.
“If we could find a way to enhance the production of hyaluronic acid in muscle stem cells in older people, it could help with muscle repair.”
The tests carried out to reach these results have been done in a group of mice and in human tissues in the laboratory. Thanks to this, they also found that muscle stem cells are responsible for controlling the production of hyaluronic acid using epigenetic marks in the Has2 gene.
Researchers have emphasized that aging is associated with muscle weakness, chronic inflammation, and a reduced ability of muscle stem cells to wake up and repair damage. “If we could find a way to enhance the production of hyaluronic acid in muscle stem cells in older people, it could help with muscle repair,” explains Dr. Kiran Nakka, another of the researchers.
As the authors explain, the regenerative effect of hyaluronic acid could depend on its being produced by muscle stem cells, so they are examining whether drugs that modify the epigenetics of muscle stem cells could be used to increase the generation of this acid hyaluronic
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