Nature (May 6): Brain Reward Circuit Inhibited by Next-Generation Weight-Loss Drugs — UVA Team Shows Small-Molecule GLP-1s Engage Central Amygdala Glp1r+ Neurons
A Nature paper published May 6 from a University of Virginia team developed humanized GLP1R mouse models to investigate how small-molecule GLP1R agonists — including orforglipron (Foundayo) — regulate feeding behavior. Beyond canonical hypothalamic and hindbrain networks that control metabolic homeostasis, the team showed these oral compounds recruit a discrete population of Glp1r-expressing neurons in the central amygdala and selectively suppress consumption of palatable foods by reducing dopamine release in the nucleus accumbens — a parallel hedonic-feeding circuit distinct from the homeostatic mechanism that drives most GLP-1 weight loss. The work explains why patients on small-molecule oral GLP-1s often report reduced food cravings and pleasure-driven eating, and identifies a neural circuit with implications for substance-use disorder and binge eating beyond obesity.