TNF-α抑制成熟3T3-L1脂肪细胞分泌RBP4

The tumor necrosis factor-αinhibits retinol binding protein 4 secretion in mature 3T3-L1 adipocytes

目的:观察肿瘤坏死因子-α(TNF-α)对体外培养的成熟3T3-L1脂肪细胞分泌视黄醛结合蛋白4(Retinol Binding Protein 4,RBP4)的影响。方法:体外培养3T3-L1细胞,待细胞完全融合后两天进行诱导分化为成熟脂肪细胞,应用不同浓度的重组TNF-α干预,采用放射免疫分析法检测干预后不同时间成熟脂肪细胞RBP4的分泌量。结果:(1)不同浓度TNF-α(0.2、1.0、5.0、10ng/ml)对脂肪细胞RBP4的分泌均有抑制作用,其抑制效应呈剂量依赖性:随着TNF-α浓度的增加,RBP4水平降低越加明显。(2)各实验组随着干预时间延长,RBP4虽有降低之趋势,但组内各时间点差异无统计学差异。(3)二元回归分析提示TNF-α对RBP4有影响。结论:TNF-α能抑制成熟脂肪细胞RBP4的分泌,其抑制效应有剂量依赖性,而与干预时间无关。

Objective：To explore the effects of tumor necrosis factor-or （TNF-α） on retinol binding protein 4 （RBP4） secreted by mature 3T3-L1 adipocytes in-vitro. Methods：3T3-L1 preadipocytes were cultured and differentiated into the mature adipocytes after 2 days of confluenence. Recombinant TNF-α at different concentrations was added to the culture medium of fully differentiated adipocytes. Total protein of RBP4 secreted by these adipocytes was evaluated by radioimmunoassay（RIA） at various times. Results： （1）Treatment of mature 333-L1 adipocytes with TNF-α at different concentrations （0.2,1.0,5.0, 10ng/ml） decreased RBP4 secretion. The inhibitive effect of TNF-α on RBP4 was in dose dependent manner. The level of RBP4 decreased along with the elevated TNF-α concentration in the culture medium. （2）Almost the RBP4 secretion in all experiment groups had a decreasing tread at different time points,but there was no statistical difference in each group. （3） Regression analysis indicated TNF-α had significant associations with RBP4. Conclusion：TNF-α inhibits mature adipocytes RBP4 secretion in-vitro in dose-response effects, but there is no time-response effects.