NF-κB p65在高糖诱导3T3-L1脂肪细胞胰岛素抵抗中的作用

The Role of NF-κB p65 in Insulin Resistance Induced by High Glucose in 3T3-L1 Adipocytes

建立高糖诱导胰岛素抵抗的细胞模型,研究高糖对3T3-L1脂肪细胞NF-κB p65表达及转位的影响。诱导成熟的3T3-L1脂肪细胞与5.0mmol/L的葡萄糖含或不含0.6nmol/L的胰岛素(LGIns+组与LGIns-组)或者与25.0mmol/L葡萄糖含或不含0.6nmol/L的胰岛素(HGIns+组与HGIns-组)培养18h,以2-脱氧-[3H]-D-葡萄糖摄入法观察葡萄糖的转运率,用Western印迹检测总NF-κBp65及核NF-κB p65的表达,用激光扫描共聚焦(CLSM)对NF-κB p65进行定位显示。结果显示,仅HGIns+组,即3T3-L1脂肪细胞与25.0mmol/L葡萄糖含0.6nmol/L的胰岛素培养18h后,胰岛素刺激的葡萄糖转运减少55%(P<0.01),同时Western印迹和CLSM均显示NF-κB p65核转位增加(P<0.01),但对3T3-L1脂肪细胞总NF-κB p65的表达无明显影响(P>0.05)。研究结果表明,只有在胰岛素(0.6nmol/L)存在的条件下,高糖(25.0mmol/L)才可以诱导胰岛素抵抗,其分子机制可能与其刺激NF-κB p65的核转位,调节相关基因的表达有关。

This study was carded out to establish insulin-resistant cell model induced by high glucose and to investigate the effect of high glucose on NF-κB p65 expression and translocation in 3T3-L1 adipocytes. 3T3-L1 adipocytes were treated for 18 h with DMEM （1%FBS） containing 25 mmol/L glucose with or without 0.6 nmol/L insulin, or 5 mmol/L glucose with or without 0.6 nmol/L insulin. 2-deoxy-[^3H]-D-glucose method was used for the determination of glucose uptake. Western blot was used for the determination of the protein expression of total NF-κB p65 and nuclear NF-κB p65. Confocal laser scanning microscope （CLSM） was used to investigate the distribu- tion of NF-κB p65. Only in HGIns^＋ group, namely 3T3-L1 adipocytes were treated for 18 h with DMEM （1%FBS） containing 25 mmol/L glucose with 0.6 nmol/L insulin, the insulin-stimulated glucose transport of 3T3-L1 adipose cells were decreased by 55%. Both the expression of nuclear NF-κB p65 and nuclear translocation of NF-κB p65 was increased. But total NF-κB p65 protein abundance was no change during this study. These results showed only in the presence of 0.6 nmol/L insulin, high glucose can induced insulin resistance and the molecular mechanism of which might be associated with the activation and translocation of NF-κB p65.