When we tear muscles “internal stem cells repair the problem. We see this happen not only in severe muscle wasting diseases such as muscular dystrophy and in veterans of war who endure catastrophic injuries, but also in our daily lives when we pull a muscle.
Also as we grow older and become weak we lose a lot of our muscles and our stem cells are unlikely to be able to function as well as our age.
These muscle stem cells are invisible engines that guide the growth and repair of the tissue after such injuries. But it has been difficult to grow these cells in the laboratory and then use them to replace damaged muscles therapeutically.
Researchers at the Australian Institute of Regenerative Medicine at Monash University in Melbourne, Australia have discovered a feature that encourages these muscle stem cells to shrink and heal. In a mouse model of severe muscle damage, injection of this naturally occurring protein caused complete regeneration of muscles and return to normal movement after severe muscle strain.
The research, led by Professor Peter Currie, Director of the Australian Institute of Rehabilitation Medicine at Monash University, is published today in Nature.
The scientists studied skeletal muscle regeneration in zebrafish, fast-growing as an animal model for the study of gas cell regeneration because but fish are rapidly reproducible, easier to handle experimentally, and co at least 70 percent of his genes are shared with humans. . It is also obvious that allows scientists to see the true regeneration in living muscle.
By studying the cells that migrated to muscle injury in these fish, the scientists identified a group of immune cells, called macrophages, that seemed to have a role in causing the muscle cell regeneration. “What we saw were macrophages literally chewing muscle stem cells, which then began to divide and expand. As soon as they started this process, the macrophage would move on. then chewing on the next muscle cell, and very quickly the injury would heal, “said Dr. Currie said
Macrophages are the cells that go to the site of any injury or disease in the body, removing debris and promoting healing. “They are the cleansing team of the immune system,” said Dr Currie.
It has long been thought that there are two types of macrophages in the body: those that move to the injury quickly and remove debris, and those that enter more slowly and sticking around cleansing in the long run.
However, the research team found that there were eight genetically different types of macrophages at the site of the injury, and that one type, in particular, was the “cuddler”. Further research showed that this loving macrophage released a substance called NAMPT.
By removing these macrophages from the zebrafish and adding the NAMPT to the aquarium water the experts discovered that they could stimulate the muscle stem cells to grow and heal “effectively replacing the need for the macrophages ”.
Importantly, recent experiments applied a hydrogel pad containing NAPMT to a mouse model of muscle spasm, what Dr. Currie called a major regeneration of the damaged muscles. The researchers are now in talks with several biotechnology companies about bringing NAMPT into clinical trials for the use of this fertilizer in the treatment of muscle disease and injury.
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