The recent surge in popularity of weight loss drugs like Ozempic, collectively called GLP-1s, has sparked renewed scientific interest in understanding how our bodies regulate muscle growth. In a recent study, scientists have linked the protein BCL6 to the maintenance of muscle mass and further suggested that BCL6-boosting therapeutics could help GLP-1 users retain muscle while losing fat.
Similar therapies could also be used to treat other populations prone to muscle loss, such as older adults and patients with systemic diseases like sepsis or cancer.
New study finds key protein to maintain muscle mass
A new study from the Salk Institute has revealed that a protein called BCL6 is key to maintaining healthy muscle mass. The experiments showed that mice with lower levels of BCL6 had significantly reduced muscle mass and strength, but increasing BCL6 successfully reversed those losses.
The results suggest that pairing GLP-1 medications with a BCL6-boosting drug may help counteract unwanted muscle loss. Similar therapies could also be used to treat other populations prone to muscle loss, such as older adults and patients with systemic diseases like sepsis or cancer.
The findings were published in the Proceedings of the National Academy of Sciences on January 22, 2025. “Muscle is the most abundant tissue in the human body, so its maintenance is critical to our health and quality of life,” says Ronald Evans, professor and director of the Gene Expression Laboratory at Salk.
Potential therapies for muscle loss
“Our study reveals how our bodies coordinate the upkeep of all this muscle with our nutrition and energy levels, and with this new insight, we can develop therapeutic interventions for patients losing muscle as a side effect of weight loss, age, or illness.” Ronald added.
Through a series of subsequent experiments, several results were yielded. According to the study by the Salk Institute, fasting promotes the secretion of growth hormone, which reduces BCL6 levels in muscle cells. BCL6 is a regulator of SOCS2, so less BCL6 leads to less SOCS2.
At normal levels, BCL6 controls how much SOCS2 is expressed and, therefore, how much IGF1 is produced. In animals without BCL6, the lack of control over SOCS2 slowed IGF1 production so much that muscles became weaker and smaller.