Effect of substitution of soy protein for dietary casein on blood glucose, liver enzymes, lipid profile and kidney function in diabetic rats

ABSTRACT

The present study was carried out to investigate effects of substitution of Soy protein [SP] for dietary casein [CA] on blood glucose level, liver enzymes, total cholesterol, lipoproteins and kidney function in diabetic rats. The experiment was performed on 60 mature male rats distributed into 6 groups. One group was kept as a -ve control [non diabetic], while the other groups were rendered diabetic by subcutaneous injection of alloxan. The diabetic rats were assigned to one of five diets viz. 20% casein [CA]; 5% Soy protein [SP] + 15% [CA]; 10% [SP] + 10% [CA]; 15% [SP] + 5% [CA] or 20% [SP]. At the end of dietary period [6 weeks], the rats were sacrificed and blood was collected for separating the serum. Blood glucose, liver enzymes [AST, ALT and ALP], total cholesterol and lipoprotein fractions as well as urea nitrogen, uric acid and creatinine concentrations were determined in the serum. The obtained results showed that substitution of Soy protein for dietary casein significantly decreased the levels of blood glucose, AST, ALT and ALP enzymes and reduced serum levels of total cholesterol, triglycerides, LDL-C, VLDL-c, while increased the level of HDL-c in diabetic rats. It decreased also the concentrations of blood urea nitrogen, uric acid and creatinine. In conclusion, consumption of Soy protein instead of casein may be useful for diabetic patients as it lowers blood glucose and reduces the adverse effects of diabetes on kidney and liver