高糖、高脂诱导大鼠肝脏胰岛素抵抗评价

目的:比较高糖、高脂等不同饮食诱导大鼠肝脏胰岛素抵抗模型的差异.方法:SD大鼠分成4组,分别给予普通、高糖、高脂、高糖高脂饲料,12周后检测各组空腹血糖水平、葡萄糖耐量、空腹血清胰岛素水平(FI)、胰岛素抵抗指数(HOMA-IR)、肝糖原含量及肝脏葡萄糖转运体2(GLUT2)、葡萄糖转运体4(GLUT4)表达水平.结果:口服糖耐量试验中,高脂组、高糖高脂组血糖曲线下面积分别为(91.6±5.5)和(106.1±4.6)mmol·min·L-1,较对照组明显增大(P<0.05或0.001).高脂组的FI与HOMA-IR分别为(20.2±0.9) μIU·L-1和(5.1±0.3),高糖高脂组则分别为(31.4±2.0) μIU·L-1 和(8.2±0.7),均较对照组显著升高(P<0.05或0.001).高糖高脂组的肝糖原含量为(1.3±0.0) mg·g-1,也较对照组显著增多(P<0.01).高脂组和高糖高脂组的GLUT2表达分别为(75.8±4.0)%和(60.0±4.5)%,均比对照组明显降低(P<0.05或0.001);高糖、高脂、高糖高脂组的GLUT4表达分别为(60.6±5.2)%,(72.3±3.8)%,(57.1±2.9)%,同样较对照组显著降低(P<0.001).结论:高糖结合高脂饮食更适合胰岛素抵抗模型的制备.

Comparison of High Fat and/or High Sugar induced Hepatic Insulin Resistance in Rats

Objective: To compare the differences between high fat and/or high sugar-induced insulin resistance model in rats.Method: Sprague-Dawley rats were divided into four groups and fed with common,high-sugar(HS),high-fat(HF) or high-sugar high-fat(HSF) diet for 12 weeks.Fasting blood glucose levels,glucose tolerance,fasting serum insulin levels(FI),homeostasis model assessment of insulin resistance(HOMA-IR),hepatic glycogen contents and expression levels of GLUT2 and GLUT4 in livers were evaluated in each group.Result: In oral glucose tolerance test,the area under the curve of time-blood glucose of HF((91.6±5.5) mmol·min·L-1,P<0.05) and HSF((106.1±4.6) mmol·min·L-1,P<0.001) groups were significantly larger than that of the control group.In comparison to FI and HOMA-IR in control group,both of the levels were significantly higher in HF((20.2±0.9) μIU·L-1,5.1±0.3,P<0.05) and HSF((31.4±2.0) μIU·L-1,8.2±0.7,P<0.001) groups.The hepatic glycogen contents of rats in HSF group were significantly lower((1.3±0.0) mg·g-1,P<0.01) than that in control group.The expression levels of GLUT2 protein in rats’ liver in HF(75.8%±4.0%,P<0.05) and HSF(60.0%±4.5%,P<0.001) groups were significantly lower than that in control group.The expression levels of GLUT4 protein of rats in HS(60.6%±5.2%,P<0.001),HF(72.3%±3.8%,P<0.001) and HSF(57.1%±2.9%,P<0.001) groups were all significantly lower than that of control group.Conclusion: The results indicated that the high-sugar high-fat diet could establish a more successful rat model of hepatic insulin resistance.