TL;DR
Older muscles heal more slowly and waste away more easily, and a team at Kyushu University in Japan thinks it has found one reason. The signal that wakes muscle's repair cells, a protein called HGF, is still there in older bodies; it is chemically damaged, so it grips its receptor less well. In test-tube work, an antioxidant called lipoic acid trisulfide, or LASSS, fixed that grip: the treated protein, which the authors nicknamed "Super HGF," bound its receptor more than twice as tightly as untreated HGF. In mice whose muscles were wasting from disuse, the same antioxidant cut the damage itself. That points to a fresh way to keep muscle strong with age: repair the healing signal the body already makes instead of adding more of it. The next step is to see whether stronger grip means stronger muscle in older animals. To see our odds on when a repaired repair signal could reach people, and the timeline of muscle breakthroughs that leads there, subscribe.
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