【摘要】 目的探讨地塞米松和胰岛素联合作用诱导3T3-L1脂肪细胞产生胰岛素抵抗后,罗格列酮改善抗性细胞摄取葡萄糖的途径。方法在地塞米松和胰岛素诱导3T3-L1脂肪细胞产生胰岛素抵抗后,加入10-5mol/L罗格列酮,作用48 h改善细胞抗性,提取细胞总RNA和总蛋白,Western blot显示葡萄糖转运子(GLUT4)丰度,RT-PCR检测GLUT4和信号分子c-Cbl相关蛋白(c-Cbl associated protein,CAP)的基因表达。结果1罗格列酮显著增加了细胞GLUT4的转录水平和翻译水平,其表达丰度介于正常组与抵抗组之间。2罗格列酮提高了CAP基因水平,增强经CAP途径调节的GLUT4的转位。结论罗格列酮可能通过启动其下游基因GLUT4和CAP基因表达,增加GLUT4的数目,并激活CAP信号途径,提高GLUT4向细胞膜的转位,改善细胞对葡萄糖的摄取,从而改善胰岛素抵抗。更多还原

【Abstract】 Objective To study the mechanism of rosiglitasone to improve glucose-uptake of 3T3-L1 adipocyte with insulin resistance induced by dexamethasone and insulin.Methods Insulin resistance was induced to 3T3-L1 adipocyte after chronic treatment of dexamethasone and insulin.The insulin resisted 3T3-L1 adipocyte was treated with 10-5 mol/L of rosiglitasone for 48 h.The mRNA,protein of glucose transporter GLUT4 and CAP gene were then examined.Results ① Rosiglitasone increased the expression of GLUT4 mRNA and protein inhibited by dexamethasone and insulin although it had not reached a normal level.② Rosiglitasone increased the mRNA of CAP,which remained unchanged during insulin resistance.Conclusion Rosiglitasone,an insulin sensitizer,might up-regulate GLUT4 and CAP along with the peroxisome proliferators activated receptor gamma(PPAR-γ),which not only increases the GLUT4,but also activates the CAP-depended signaling pathway;improves the translocating of GLUT4 to the cell membrane;and increases the ability of glucose-uptake of cells.更多还原