姜黄素促进骨骼肌GLUT4转位改善糖尿病大鼠胰岛素抵抗

目的:研究姜黄素对STZ诱导糖尿病大鼠骨骼肌胰岛素抵抗的影响及其机制。方法:雄性SD大鼠腹腔注射STZ诱导糖尿病大鼠模型。成模大鼠分为糖尿病组(DM)，糖尿病＋姜黄素组(DM＋Cur)，糖尿病＋缓冲液对照组(DM＋NC)。以正常SD大鼠为正常对照组(NC)。DM＋Cur组予姜黄素灌胃治疗，DM＋NC组给予等体积缓冲液灌...

Curcumin ameliorates insulin resistance via enhancing GLUT4 translocation in skeletal muscle in streptozocin-induced diabetic rats

Objective To investigate the effects and mechanisms of curcumin on insulin resistance in streptozocin-induced diabetic rats.Methods Diabetic rats were induced by intraperitoneal injection of STZ,then all the rats were randomly divided into diabetes(DM),diabetes+curcumin(DM+Cur),and diabetes+buffer control(DM+NC)groups.Normal SD rats were used as control group(NC).The DM+Cur group was treated with curcumin,while the DM+NC group was treated with equal-volume buffer.The test lasted 12 weeks.The blood glucose was detected,and hyperinsulinemic-euglycemic clamp test was performed to estimate peripheral insulin resistance.At the end of the experiments,rats were killed and the total protein and cell membrane protein were extracted from skeletal muscle.The levels of phosphorylated PI3K,phosphorylated AKT,total PI3K,and total AKT were measured by Western blot.The levels of total GLUT4 and GLUT4 of cell membrane were also detected by Western blot,GLUT4 levels in skeletal muscle cell membranes were detected by immunofluorescence.Results Blood glucose levels of DM+Cur group were lower than those of DM group[(18.67±1.99 vs 24.38±2.88)mmol/L,P<0.05],and insulin resistance was also improved[the average GIR(14.69±0.29 vs 10.25±0.30)mg·kg-1·min-1,P<0.01].The phosphorylation levels of PI3K and AKT were increased,and GLUT4 translocation to the cell membrane was increased.Conclusion By activating the PI3K/AKT pathway,curcumin promotes GLUT4 translocation,increases skeletal muscle glucose uptake,and finally improves insulin resistance.