Scientists have discovered how a naturally occurring hormone can reverse obesity in mice, and the answer lies in the brain. Researchers at the University of Oklahoma found that the hormone works by sending signals to a brain region that helps control metabolism and appetite. This is the same general area targeted by widely used GLP-1 weight loss drugs. The findings were published in the journal Cell Reports . The hormone, known as FGF21 (fibroblast growth factor 21), has already attracted attention as a potential target for new therapies. Drugs designed to act on this pathway are currently being tested in clinical trials for MASH (metabolic dysfunction-associated steatohepatitis), a serious form of fatty liver disease. Lead researcher Matthew Potthoff, Ph.D., and his team focused on understanding exactly how FGF21 produces its effects. Their results show that the hormone acts through the hindbrain, which is located in the lower back part of the brain.…