Hormone helps prevent muscle loss, study finds

A hormone known to prevent weight gain and normalize metabolism can also help maintain healthy muscles in mice, according to a new study published in the American Journal of Physiology-Endocrinology and Metabolism.

In the study, treating mice on a high-fat diet with MOTS-c helped prevent obesity-associated muscle atrophy by decreasing levels of myostatin, a protein that inhibits muscle growth. Myostatin levels were 40 percent lower in MOTS-c treated mice compared to control mice. The researchers also found that higher MOTS-c levels in humans were correlated with lower levels of myostatin. The findings show MOTS-c improves not only metabolic function but muscle mass as well, the researchers said.

Through molecular analysis, the researchers also identified the specific signaling pathway regulated by MOTS-c, demonstrating that MOTS-c modulates the CK2-PTEN-AKT-FOXO1 pathway to inhibit myostatin expression and muscle wasting, and suggesting that the exercise mimetic effect of MOTS-c may be derived from its previously unknown role as a myostatin inhibitor, according to the study.

Though several other myostatin inhibitors have been identified, they have yet to successfully reduce muscle wasting conditions in clinical trials. This may be because improving muscle mass alone is not enough, the researchers said. The researchers said they believe boosting mitochondrial function is also key and say that MOTS-c-derived treatments could be especially promising in this regard.

The findings, researchers said, present new possibilities for treating muscle-wasting conditions associated with age, obesity, or cancer.