Soy-ghretropin, a novel ghrelin-releasing peptide derived from soy protein

作者：Nakato Junya; Aoki Hayato; Iwakura Hiroshi; Suzuki Hideyuki; Kanamoto Ryuhei; Ohinata Kousaku^*

来源：FEBS LETTERS, 2016, 590(16): 2681-2689.

DOI：10.1002/1873-3468.12306

• food protein
• ghrelin
• peptide
• structure-activity relationship

We investigated exogenous secretagogues of ghrelin, which is an orexigenic hormone isolated from the stomach. We found that the tryptic digest of soy beta-conglycinin stimulated ghrelin secretion by the ghrelin-producing cell line, MGN3-1. We then identified a 22-amino acid peptide corresponding to the beta-conglycinin alpha-subunit(192-213) [beta CG alpha(192-213)] from an active fraction separated by HPLC. The N-terminal undecapeptide of beta CG alpha(192-213), NKNPFLFGSNR, exhibited ghrelin-releasing activity at a lower dose than that of beta CG alpha(192-213). We named NKNPFLFGSNR 'soy-ghretropin', which corresponds to beta CG alpha(192-202). Neither [des-(NK2)-K-1]-soy-ghretropin nor [des-R-11]-soy-ghretropin stimulated ghrelin secretion; hence, both the N- and C-terminal structures of soy-ghretropin were indispensable. Orally administered soy-ghretropin increased plasma ghrelin levels and food intake in vivo. Soy-ghretropin is the first exogenous ghrelin-releasing peptide derived from food protein.

• 出版日期2016-8