Figure 1: The role of adipose tissue- (AT-) gut-brain axis peptides in long-term and short-term regulation of food intake. Long-term regulators are adipose-derived food intake-inhibiting hormone leptin or food intake-stimulating hormone neuropeptide Y (NPY) mainly produced by the hypothalamus and also cosecreted with synthesized catecholamines in AT. Hormones produced in the gut are short-term food intake-stimulating hormone ghrelin, or food intake-inhibiting peptide YY (PYY), pancreatic polypeptide (PP), cholecystokinin (CCK), insulin, and putative anorexigen obestatin (the hypothalamus (violet), nucleus tractus solitarius (NTS, blue), sympathetic and serotoninergic areas (red), and vagal nerve parasympathetic area (green)).