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【目的】探讨肿瘤坏死因子琢(TNF琢)对体外培养的人脂肪细胞胰岛素刺激的葡萄糖摄取和胰岛素受体底物1(IRS-1)酪氨酸磷酸化的影响,为多囊卵巢综合征(PCOS)的胰岛素抵抗(IR)病因学研究提供新的实验依据。【方法】脂肪细胞葡萄糖摄取的测定采用3H标脱氧右旋葡萄糖(2-[3H]DG)吸收法,IRS-1酪氨酸磷酸化的检测采用免疫沉淀、Western印迹和增强化学发光蛋白免疫印迹法及图像分析。【结果】①胰岛素(100nmol/L)作用下,TNF琢刺激浓度分别为0、5ng/mL、10ng/mL、20ng/mL时,脂肪细胞2-[3H]DG的摄取分别为(652±203)U,(609±172)U,(511±135)U和(404±168)U,当TNF琢刺激浓度达20ng/mL时,脂肪细胞对葡萄糖摄取的降低有显著性差异(P<0.05)。②胰岛素(100nmol/L)刺激下IRS-1的酪氨酸磷酸化在TNF琢(5ng/mL)作用时(74.50%±16.86%)较无TNF琢作用(94.00%±14.70%)有所降低,但无显著性差异;当TNF琢刺激浓度分别为10ng/mL(31.16%±10.44%)和20ng/mL(27.33%±9.63%)时,胰岛素(100nmol/L)刺激后IRS-1的酪氨酸磷酸化明显降低(P<0.001)。【结论】①TNF琢刺激浓度的升高可抑制体外培养的人脂肪细胞胰岛素刺激的葡萄糖摄取。②TNF琢可抑制体外培养的人脂肪细胞胰岛素刺激的IRS-1的酪氨酸磷酸化,并存在一定的量效关系,可能阻碍了胰
【Objective】 To investigate the effect of tumor necrosis factor (TNF) on insulin-stimulated glucose uptake and insulin receptor substrate 1 (IRS-1) tyrosine phosphorylation in cultured human adipocytes, (PCOS) insulin resistance (IR) etiology provide new experimental evidence. 【Method】 Glucose uptake in adipocytes was determined by 3H-deoxy-dextrose (2- [3H] DG) absorption assay, and IRS-1 tyrosine phosphorylation was detected by immunoprecipitation, Western blotting and chemiluminescence immunoassay Law and image analysis. 【Results】 ① In the presence of 100 nmol / L insulin, the uptake of 2- [3H] DG in adipocytes was (652 ± 203) mg / L, 10 ng / mL and 20 ng / mL, respectively ), U (609 ± 172) U, (511 ± 135) U and (404 ± 168) U, respectively. There was a significant difference in the decrease of glucose uptake when TNF stimulation was 20ng / mL ). ② The tyrosine phosphorylation of IRS-1 stimulated by insulin (100nmol / L) was reduced (74.50% ± 16.86%) compared with that of non-TNF control (94.00% ± 14.70%) , But there was no significant difference. When stimulated by 100nmol / L insulin, the concentration of IRS-1 was significantly increased at 10ng / mL (31.16% ± 10.44%) and 20ng / mL (27.33% ± 9.63% Adenine phosphorylation was significantly reduced (P <0.001). 【Conclusion】 (1) The increased concentration of TNF-α can inhibit insulin-stimulated glucose uptake in cultured human adipocytes. ②TNF Zhuo inhibition of human adipocyte insulin-stimulated IRS-1 tyrosine phosphorylation in vitro, and there is a certain dose-effect relationship, may hinder the pancreas