ABSTRACT
Objective:To identify a novel bombesin bioactive peptide from the skin secretion of Hylarana Latouchii, and to explore its effect on insulin secretion in islet cells.Methods:The skin secretion from Hylarana Latouchii was extracted by electrical stimulation, and the single chain of bombesin peptide was cloned and sequenced. The peptide QUB2995 was synthesized via solid-phase synthesis, then purified using reversed-phase high performance liquid chromatography (HPLC). Matrix assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF) was applied to validate. QPCR and ELISA were used to probe the effect of QUB2995 on insulin secretion in MIN6 and INS-1 cells.Results:A novel bombesin peptide named QUB2995 (GAFGDFLKGAAKA GALKILSIAQCKLSGTC) was found in the skin secretion of Hylarana Latouchii through molecular cloning. The bioactive peptide could significantly promote the proliferation and insulin secretion from mouse islet MIN6 cells and rat islet INS-1 cells. The effect reached a climax at the concentration of 10 -5 mol/L. Conclusion:A novel bombesin bioactive peptide named QUB2995 was found from Hylarana Latouchii. It could significantly promote insulin secretion in MIN6 cells of mouse islets and INS-1 cells of rat islets, indicating its potential in the treatment of diabetes.