beneficial effect of vitamin E supplementation on zinc status, carbohydrate metabolism, transaminases and alkaline phosphatase activities in alloxan-diabetic rats fed on zinc deficiency diet

ABSTRACT

The aim of this study was to investigate the beneficial effect of vitamin E supplementation on zinc deficiency in experimental diabetes. Male alloxan-diabetic Wistar, albino rats of 10 weeks of age were divided into three groups. The first group received a diet containing 54 mg zinc/kg [adequate zinc group, AZ], the second group received a diet containing 1mg zinc/kg [zinc deficient group, ZD], and the third group received a diet containing 1mg zinc/kg supplemented with vitamin E [500mg/kg diet] [ZD+VE]. Body weight gain and food intake of all rats were recorded regularly over a period of four weeks. On day 28, after overnight fasting, animals were killed and blood glucose, serum cholesterol, serum triglycerides, serum protein, serum urea, serum zinc, femur zinc, pancreatic zinc, testis zinc, liver glutathione concentrations and serum glutamic oxalic transaminase [GOT], serum glutamic pyruvic transaminase [GPT] and serum alkaline phosphatase activities were determined on blood and tissue samples. Body weight gain of zinc deficient diabetic animals at the end of four weeks of dietary manipulation was significantly lower than that of zinc adequate diabetic animals. Dietary zinc intake significantly increased blood glucose, serum cholesterol, serum triglycerides, and serum urea of zinc deficient diabetic rats. In contrast, serum zinc, femur zinc, pancreatic zinc, serum protein and liver glutathione levels were lower. The consumption of zinc deficient diet led also to an increase in serum GOT, GPT coupled with a decrease in serum alkaline phosphatase. Vitamin E ameliorated all the previous parameters. In conclusion, the present study demonstrates that vitamin E supplementation significantly reduced the severity of zinc deficiency in diabetes mellitus