Free Fatty Acid Receptor GPR120 and Pathogenesis of Obesity and Type 2 Diabetes Mellitus

G protein-coupled receptor 120 (GPR120) was initially identified as an orphan receptor through mining the human genome databases. In 2005, GPR120 was deorphanized and shown to be a receptor for long-chain free fatty acids. GPR120 regulates various physiological processes, including gut hormone secretion, islet function, food preference, osteoclastogenesis, anti-inflammation, adipogenesis, and appetite control. Recently, a human genetic study conducted in European populations identified a loss-of-function GPR120 mutation associated with obesity and insulin resistance. Therefore, GPR120, the sensing receptor for long-chain free fatty acids, represents a novel drug target for the treatment of obesity and diabetes.