Activation of corticotropin-releasing factor receptor 2 beta (CRFR2 beta) results in increased skeletal muscle mass and the prevention of muscle atrophy. Using a luciferase reporter assay, we screened 357 functional food factors that activate CRFR2 beta and, subsequently, confirmed that nobiletin (NBT) increases CRFR2 beta activity. Additionally, we found that NBT augments the activity of the endogenous peptide ligand urocortin 2 (Ucn2) in a concentration-dependent manner. Computational simulation of CRFR2 beta confirmed that transmembrane domains (TMs) 1 and 2 are important for the synergistic activity of NBT and also identified important amino acids in these domains. Finally, we demonstrated that a co-administration of Ucn2 and NBT increases the hypertrophic signal in mouse skeletal muscle. These observations demonstrate that NBT can activate CRFR2 beta and amplify the agonistic activity of Ucn2 and that such food-derived molecules have the potential to enhance endogenous G protein-coupled receptor ligand activities and contribute to the maintenance of skeletal muscle mass and function. (C) 2020 Elsevier Inc. All rights reserved.