Whey protein upregulates muscle insulin receptor tyrosine kinase and is comparable to vildagliptin as insulin-sensitizer
Background and aims: Whey protein is a natural product with anti-hyperglycemic effect. This study aimed to evaluate the possible therapeutic effect of different concentration of whey protein compared to vildagliptin on type 2 diabetes mellitus rat model and to clarify the underlying molecular mechanisms. Material and method: sixty male Wistar rats were divided into six groups: normal control, diabetes control, vildagliptin treated diabetic group, whey protein 10%, 20%, and 40% treated groups. Results: each of vildagliptin and whey protein exhibited anti-hyperglycemic and insulinotropic effect in diabetic rats however, the effects obtained by 40% whey protein was comparable to that of vildagliptin. The biochemical results were supported by the histopathological finding which showed significant increase in the number of β-cells in both vildagliptin and 40% whey protein versus the control group. Interestingly, 40% Whey protein was superior to vildagliptin in increasing the level of muscle insulin receptor tyrosine kinase (IRTK) thereby increase sensitivity to insulin. Conclusion: the anti-hyperglycemic effect of whey protein was concentration-dependent and mediated by increasing intestinal incretin hormones, muscle (IRTK), and number of β-cells. 40% whey protein was comparable to vildagliptin as antihyperglycemic drug proved insulin-sensitizing effect. It could be used safely as a substitute for diabetic patients.