Turns out metformin, the go-to diabetes drug, isn't just about blood sugar.
Researchers at Baylor College of Medicine found it also tweaks brain activity by shutting down a protein called Rap1 in a part of the brain that helps control energy and glucose.
When they tested mice missing this protein, metformin didn't work, showing how important the brain's role is in how this drug works.
New treatment avenues
The team found that SF1 neurons are activated when metformin is introduced into the brain, suggesting these neurons are directly involved in the drug's action.
This could open up new ways to treat diabetes by targeting the brain directly, and might even explain why metformin is linked to slower brain aging.
Scientists are excited to see what other surprises this old drug might have in store.