Metformin's brain action unveiled: Rap1 in the hypothalamus lowers blood sugar

Researchers find metformin lowers blood sugar by acting in the brain, specifically by suppressing Rap1 in the ventromedial hypothalamus to activate SF1 neurons. These effects occur at tiny brain doses, suggesting a brain pathway adds to the drug’s known liver and gut actions and could inspire new diabetes therapies and broadened understanding of metformin’s brain benefits.