Boarfish (Capros aper) protein hydrolysate has potent insulinotropic and GLP-1 secretory activity in vitro and acute glucose lowering effects in mice.

The antidiabetic actions of a boarfish protein hydrolysate (BPH) were investigated in cultured cells and mice. A boarfish (Capros aper) muscle protein hydrolysate was generated using the enzymes Alcalase 2.4L and Flavourzyme 500L. Furthermore, the BPH was subjected to simulated gastrointestinal digestion (SGID). BPH and SGID samples (0.01-2.5 mg/ml) were tested in vitro for DPP-IV inhibition andinsulin and GLP-1 secretory activity from BRIN-BD11 and GLUTag cells, respectively. The BPH and SGID samples, caused a dose-dependent increase (4.2 to 5.3-fold, p<0.001) in insulin secretion from BRIN-BD11 cells and inhibited DPP-IV activity (IC50 1.18±0.04 and 1.21±0.04 mg/ml), respectively. The SGID sample produced a 1.3-fold (p<0.01) increase in GLP-1 secretion. An oral glucose tolerance test (OGTT) was conducted in healthy mice (n=8), with or without BPH (50 mg/kg bodyweight). BPH mediated an increase in plasma insulin levels (AUC(0-120 min), p<0.05) and a consequent reduction in blood glucose concentration (p<0.01), after OGTT in mice versus controls. The BPH showed potent antidiabetic actions in cells and improved glucose tolerance in mice.