The Caprine casein-alpha-S2 protein modulates the molecular mechanism of insulin signal transduction in type 2 diabetes rat

The purpose of this study was to investigate the association of casein-alpha-S2 protein of Caprine milk and molecular mechanism of insulin signal transduction in type 2 diabetes mellitus (T2DM). We divided 24 experimental rats into two major groups, namely control and DM group. The Caprine milk CSN1S2 protein treatment of 0, 375, 750, and 1500 mg/kg BW was administered to the control and DM rats. We observed several physiological parameters of all rats. The levels of insulin and TNF-α in the plasma were measured using ELISA. The expressions of proteins and mRNA levels of diabetes-related genes in the pancreas tissues were analyzed using Western Blotting and Real-Time PCR, respectively. Our study found that there was no improvement in the blood glucose and cholesterol level of DM rats treated with CSN1S2. Interestingly, the expression of genes associated with insulin signaling was improved by the CSN1S2 protein treatment in diabetic rats. The diabetic rats showed an elevated insulin level and GLUT4 protein expression after treatment. We also reported that the CSN1S2-treated diabetic rats had a gradually reduced expression of TNF-α and VCAM1 in dose-dependent manner. Moreover, the 750 mg/kg BW of CSN1S2 treatment enhanced the mRNA expressions of INSR, GLUT4, IGF1, CAMKK, and CAMK4 in diabetic rats. The ability of Caprine milk CSN1S2 protein to regulate the molecular mechanisms in the diabetes-signaling pathway indicated its potential therapeutic effects on diabetes management.