目的:观察大鼠肝脏中氧化应激以及胰岛素抵抗的发生并探讨吡咯列酮对高脂饮食导致的大鼠肝脏胰岛素抵抗的改善作用。方法:取4周龄雄性SD大鼠,实验分为4组:对照组,高脂组,吡咯列酮组、吡咯列酮+高脂组。喂养12周后,称体重后断尾法留取空腹血标本,取血测定空腹血糖浓度、血清胰岛素,并计算胰岛素敏感指数;糖原检测试剂盒检测肝脏组织中糖原含量;DHE染色观察肝脏组织中的活性氧自由基水平。结果:正常大鼠的胰岛素敏感指数为-3.47±0.39,高脂饲料喂养12周后,大鼠空腹血糖水平上升,而胰岛素敏感指数降低为-6.29±0.54,吡咯列酮能降低血糖,增加胰岛素敏感指数为-4.54±0.33。蒽酮法的检测结果显示高脂饲料喂养大鼠肝组织糖原含量显著降低到(13.6±2.7)mg/g,吡咯列酮能促进肝脏糖原合成[(19.62±2.88)mg/g]。DHE染色显示肝组织活性氧自由基水平显著增加,吡咯列酮能降低氧化应激水平。结论:高脂饲料喂养SD大鼠胰岛素敏感指数降低,肝组织中活性氧自由基水平显著增加,糖原含量显著降低,吡咯列酮改善高脂饮食导致的大鼠肝脏胰岛素抵抗。
AIM:To observe the effect of pioglitazone on oxidative stress and insulin resistance in rats with high-fat diet. METHODS:Four-week male SD rats were chosen and divided into four groups:Control group,High-fat diet group,Pioglitazone group,Pioglitazon and high fat diet group.After 12 weeks feeding,the plasma glucose and insulin levels were detected,the insulin sensitivity index was counted.The liver intracellular glycogen content was measured using a glycogen assay kit.ROS generation in liver tissues was assessed by DHE fluorescence.RESULTS:The insulin sensitivity index of control group was-3.47±0.39 after feeding with high-fat diet for 12 weeks,the blood glucose content was increased,the insulin sensitivity index was decreased to-6.29±0.54,and pioglitazone increased the insulin sensitivity index to-4.54±0.33.The hepatic glycogen content in rats fed with high-fat diet was significantly decreased to(13.6±2.7) mg/g,confirming insulin resistance.But pioglitazone promoted hepatic glycogen content [(19.6±2.9) mg/g].The DHE dyeing in hepatic tissue slices showed the ROS level was increased in rats with a high-fat diet.However,pioglitazone could decrease the ROS level of liver.CONCLUSION:Pioglitazone improves the hepatic insulin resistance condition by degrading oxidative stress level.