饮食因素对大鼠脂肪细胞葡萄糖转运蛋白4的影响

Effect of Dietetic Ingredient on Glucose Transporter 4 in Adipocyte of Rats

目的:研究饮食因素对大鼠脂肪细胞葡萄糖转运蛋白4(GLUT4)的影响。方法:实验大鼠随机分为正常组(n=10)、模型组(n=10)和饮食干预组(n=10)。正常组以基础饲料喂养10周;模型组以高糖高脂饲料喂养10周;饮食干预组以高糖高脂饲料喂养4周后,改喂基础饲料6周。Westernblot法检测各组大鼠脂肪细胞内、外膜GLUT4含量。结果:模型组大鼠脂肪细胞内、外膜GLUT4含量均低于正常组(P<0.05)。与模型组大鼠相比,饮食干预组大鼠脂肪细胞内膜GLUT4含量无显著差异,但细胞外膜GLUT4含量增加P<0.05)。结论:高糖高脂饮食可能通过降低脂肪细胞GLUT4含量及其转位使大鼠产生胰岛素抵抗。饮食干预可提高脂肪细胞GLUT4含量并改善其转位,增加葡萄糖的摄取,提高胰岛素敏感性。

Objective: To investigate the effect of dietetic ingredient on expression and translocation of glucose transporter 4(GLUT4) in adipocyte of rats. Method: Experimental rats were rondomly divided into 3 groups:control group(n=10),model group(n=10) and diet-intervention group(n=10). Control group were fed with basic diet for 10 weeks. Model group were fed with the diet enriched with sucrose(20%,w/w), cholesterol( 2.5% ,w/w) for 10weeks. Diet-intervention group were fed with the diet enriched with sugar and fat for 4 weeks then fed with basic diet for 6 weeks. After the plasma membranes and the intracellular membranes of adipocyte were prepared and separated, GLUT4 protein was detected by Western blot analysis.Results: Western blot analysis showed that intracellular membranes and plasma membranes GLUT4 protein in adipocyte of model group rats decreased (P<0.05) as compared with that of control group rats. Intracellular membranes GLUT4 protein of diet-intervention group rats vemained unchanged and plasma membranes GLUT4 protein increased (P<0.05) as compared with that of model group rats.Conclusion: Diet enriched with sugar and fat may induce insulin resistance in rats via decreasing amount and translocation of GLUT4 in adipocyte. Diet intervention can raise the amount of GLUT4 protein in adipocyte of rats with insulin resistance and ameliorate translocation of GLUT4, which may increase the ingestion and utilization of glucose.