As mice get older, the places where nerves connect to muscles show big changes in genes tied to inflammation and tissue breakdown — especially in a key area called the neuromuscular junction — which...

As mice get older, a key cellular switch called mTORC1 in their muscles turns down genes that keep muscle structure strong, turns up genes linked to inflammation, and flips on signals seen when nerves stop talking to muscles. Giving them a drug called rapamycin helps reverse some of these changes, suggesting this switch plays a big role in how muscles age.