Washington, July 26 (SANA)Metformin, the world’s most widely prescribed drug for type 2 diabetes, lowers blood sugar through a previously unknown signaling pathway in the brain, challenging the long-held view that its effects are driven mainly by the liver and intestines, according to a new study.The research, led by scientists at Baylor College of Medicine in collaboration with international researchers and published inScience Advances, found that metformin suppresses the activity of a protein known as Rap1 in the ventromedial hypothalamus, activating neurons that help regulate blood glucose levels.According toScienceDaily, the findings suggest the brain plays a central role in the drug’s glucose-lowering effects, providing a new explanation for how metformin works after decades of widespread clinical use.Experiments in mice with type 2 diabetes showed that metformin’s ability to reduce blood sugar depended on the presence of the Rap1 protein in specific brain neurons. The drug did not produce the same effect in genetically engineered mice lacking the protein in that region of the brain.The researchers also found that injecting minute amounts of metformin directly into the brains of mice significantly lowered blood glucose levels, despite doses being thousands of times smaller than those used in oral treatment, highlighting the brain’s sensitivity to the drug.The researchers said the findings could improve understanding of metformin’s mechanism of action and support the development of new diabetes treatments targeting neural pathways involved in blood glucose regulation.