Obestatin is a 23 amino acid peptide hormone with a conserved C-terminal glycine residue and amidation site that is formed by cleavage of the ghrelin and obestatin prepropeptide.1 It binds to the orphan receptor GPR39 (Kd = 1 nM) and stimulates cAMP production in CHO and HEK293 cells overexpressing human GPR39. Obestatin inhibits contraction of isolated mouse jejunum muscle strips induced by ghrelin . In vivo, obestatin (12.5-1,000 nmol/kg) suppresses food intake in a time- and dose-dependent manner and reduces body weight gain and gastric emptying in mice. Obestatin (0.22 g per animal) also reduces food intake and glucose response without affecting plasma insulin responses in fasted high-fat diet fed mice.2
1.Zhang, J.V., Ren, P.C., Avsian-Kretchmer, O., et al.Obestatin, a peptide encoded by the ghrelin gene, opposes ghrelin's effects on food intakeScience310(5750)996-999(2005) 2.Subasinghage, A.P., Green, B.D., Flatt, P.R., et al.Metabolic and structural properties of human obestatin {1-23} and two fragment peptidesPeptides31(9)1697-1705(2010)