小檗碱抑制核因子NF-κB p65表达及转位改善游离脂肪酸诱导的3T3-L1细胞胰岛素抵抗的分子机制

Molecular Mechanism of Berberine in Improving Insulin Resistance Induced by Free Fatty Acid through In-hibiting Nuclear Trascription Factor-kB p65 in 3T3-L1 Adipocytes

目的 观察小檗碱对游离脂肪酸诱导的3T3-L1脂肪细胞胰岛素抵抗模型核因子（nucleartran-scriptionfactorkappaB，NF-κBp65）表达及转位的影响，探讨小檗碱改善胰岛素抵抗的分子机制。方法以0．5mmol／L软脂酸诱导3T3-L1脂肪细胞产生胰岛素抵抗，予以小檗碱进行干预，同时以阿司匹林作为阳性对照，用葡萄糖氧化酶法检测培液中的葡萄糖消耗量，以2-脱氧-[^3H]-D-葡萄糖摄入法观察葡萄糖的转运率，用Westernblot检测3T3-L1脂肪细胞总NF-κBp65蛋白及核NF-κBp65蛋白的表达，用激光扫描共聚焦显微镜（CLSM）对NF．．cBp65进行定位显示。结果0．5mmol／L软脂酸作用24h使3T3-L1脂肪细胞葡萄糖消耗降低41％，胰岛素刺激的葡萄糖转运抑制67％，NF-κBp65蛋白表达明显增加，CLSM显示NF-κBp65核转位增加；同时加入小檗碱或阿司匹林则可逆转上述效应。但软脂酸、小檗碱、阿司匹林对3T3-L1脂肪细胞总NF-κBp65蛋白的表达无明显影响。结论小檗碱可以改善游离脂肪酸诱导的胰岛素抵抗，其分子机制可能是小檗碱通过抑制NF-κB的活化转位调节相关基因的表达而起作用。

Objective To investigate the effect of berberine on nuclear transcription factor kappaB （NF-κB p65） expression and translocation in insulin resistant 3T3-L1 adipocytes induced by free fatty acid （FFA） and its possible molecular mechanism. Methods 3T3-L1 adipocytes were treated with palmic acid （0.5 mmol/L） to induce insulin resistance and intervened with berberine. Controlled with aspirin, the glucose consumption in the medium was determined by glucose oxidase method; glucose transportation by 2-deoxy-[^3H]-D-glucose method; protein expression of NF-κB p65 in adopocytes by Western blot; and the distribution of NF-κB p65 was displayed by confocal laser scanning microscope （CLSM）. Results Treatment with 0.5 mmol/L of palmic acid for 24 h made glucose consumption of 3T3-L1 adipocytes decrease by 41% ; the insulin-stimulated glucose transportation inhibited by 67 % ; nuclear NF-κB p65 protein expression and nuclear translocation of NF-κB p65 significantly increased. These changes were reversed by prior treatment with berberine or aspirin. But total NF-κB p65 protein expression was not responded to palmic acid, berberine and aspirin. Conclusion Berberine significantly improve the insulin resistance induced by FFA in 3T3-L1 adipocytes, its molecular mechanism might through inhibiting the activation and translocation related gene expression of NF-κB.