TNF-α对3T3-L1成熟脂肪细胞中NYGGF4小鼠同源基因表达的影响

Effects of TNF-α on NYGGF4 homologous gene expression in 3T3-L1 adipocyte

【目的】观察TNF-α对3T3-L1成熟脂肪细胞中NYGGF4小鼠同源基因表达水平以及胰岛素刺激下的葡萄糖摄取率的影响。【方法】体外培养3T3-L1前体脂肪细胞,诱导分化为成熟脂肪细胞后,应用不同浓度（10、25、50 ng/mL）重组TNF-α干预成熟脂肪细胞16 h,或以10 ng/mL重组TNF-α分别干预24、487、2 h,采用实时荧光定量RT-PCR技术检测TNF-α干预后3T3-L1脂肪细胞中NYGGF4小鼠同源基因mRNA表达水平;另外,采用[3H]-2-脱氧葡萄糖掺入法检测TNF-α干预24、48、72h后成熟脂肪细胞葡萄糖摄取率。【结果】1）不同浓度TNF-α均能显著上调3T3-L1成熟脂肪细胞中NYGGF4小鼠同源基因表达（P均〈0.001）,在0～25 ng/mL浓度范围内呈现浓度依赖性,随TNF-α干预浓度增高,NYGGF4小鼠同源基因的表达水平逐渐升高;2）TNF-α对3T3-L1成熟脂肪细胞中NYGGF4小鼠同源基因的表达调节具时间反应性,呈现随干预时间延长该基因表达逐渐上调的特征,10 ng/mL TNF-α干预人成熟脂肪细胞24 hNYGGF4小鼠同源基因mRNA表达水平即显著上调（P〈0.001）;3）TNF-α干预48 h,3T3-L1成熟脂肪细胞胰岛素刺激的葡萄糖摄取率与未干预组比较下降50%以上,干预72 h,胰岛素刺激的葡萄糖摄取受到进一步抑制。【结论】TNF-α可以上调3T3-L1成熟脂肪细胞中NYGGF4小鼠同源基因的表达,抑制3T3-L1成熟脂肪细胞胰岛素刺激下的葡萄糖摄取。

【Objective】To explore the regulative role of TNF-α on NYGGF4 homologous gene expression and insulin-stimulated glucose uptake in 3T3-L1 adipocytes. 【Methods】3T3-L1 preadipocytes were cultured and differentiated into the matured adipocytes.Fully differentiated adipocytes（Day 8） were treated with tumor necrosis factor α（TNF-α） in different concentrations（10,25,50 ng/mL） for 16 hours or TNF-α 10 ng/mL for various times（24,48,72 h）.Total RNA from these adipocytes was extracted and the levels of NYGGF4 homologous gene mRNA expression were evaluated by real-time quantitative RT-PCR.The assay of[^3H] -2-deoxyglucose uptake was performed to observe glucose transport rate in 3T3-L1 adipocyte treated with 10 ng/mL TNF-α for 24 h,48 h and 72 h. 【Results】1） Treatment of 3T3-L1 adipocytes with TNF-α significantly increased NYGGF4 homologous gene mRNA expression.The upregulative effect of TNF-α on the NYGGF4 homologous gene expression tended to be enhanced with the increasing concentrations of TNF-α and was of dose-dependent between 0 ng/mL and 25 ng/mL.2）The TNF-α-induced upregulation of NYGGF4 homologous gene mRNA expression in 3T3-L1 adipocytes was of time-correlated and tended to be reinforced with elongation of time course.There was a significant increase in the level of NYGGF4 homologous gnen mRNA when 3T3-L1 adipocytes were treated with 10 ng/mL TNF-α for 24 h（P〈0.001）.3）TNF-α treatment resulted in a marked decline of insulin-sensitive glucose transport in 3T3-L1 adipocytes.Treated 3T3-L1 adipocytes with TNF-α for 48 h,the insulin-stimulated glucose uptake decreased by over 50%.After 48 h of TNF-α exposure,the adipocytes exhibited an further decrease in insulin-stimulated glucose uptake. 【Conclusion】TNF-α may upregulate NYGGF4 homologous gene expression and inhibit insulin-stimulated glucose uptake in 3T3-L1 adipocytes.