IL-6下调血管内皮细胞组织因子抑制物表达

IL-6 inhibits tissue factor pathway inhibitor expression in human umbilical vein endothelial cells

目的:观察IL-6对脐静脉内皮细胞(HUVECs)表达组织因子途径抑制物(TFPI)的影响.方法:应用胰酶消化HUVECs并进行传代培养,用生长良好的第2、3代细胞进行试验.同时应用CCK-8测定不同浓度的IL-6(0.125～2.0 ng/ml,实验组)刺激后细胞活性变化,对照组给予培养液;应用逆转录聚合酶链反应(RT-PCR)法检测细胞内TFPI mRNA水平.结果:与对照组相比,IL-6(0.125～0.5 ng/ml)对细胞活性没有显著影响(P>0.05);IL-6增加到1 ng/ml后,作用12 h后细胞活力开始下降.IL-6(0.5 ng/ml)作用6～24 h显著下调细胞TFPI mRNA表达(P<0.05),6 h时抑制效果最强(TFPI mRNA/GAPDH mRNA均值仅为0.191),以后抑制效应渐减弱,48 h达到正常水平(TFPI mRNA/GAPDH mRNA均值为0.399).结论:提示IL-6(0.5 ng/ml)对HUVECs的活性不造成直接的影响,同时IL-6(0.5 ng/ml)在6～24 h内可抑制HUVECs的TFPI mRNA表达而诱发凝血系统失衡,这可能与急性炎性反应时相的血液凝固和血栓形成有关.

Objective:To elucidate the effects of interleukin-6(IL-6) on tissue factor pathway inhibitor (TFPI) expression in human umbilical vein endothelial cells. Methods: In experimental group,cultured human umbilical vein endothelial cells(HUVECs) were treated with IL-6 at 0.125 ng/ml,0.5 ng/m and 1.0 ng/ml for different hours. HUVECs in control group were treated with culture medium.Cell viability was then determined by cell counting kit-8(CCK-8). Cytoplasmic RNA was prepared using the TRIzol method and TFPI mRNA levels was assayed by reverse transcript polymerase chain reaction(RT-PCR). Results: IL-6(0.125-0.5 ng/ml) did not produce cell toxicity compared to the control group according to LDH determination in culture media, but IL-6(≥1.0 ng/ml) elicited a significant cytotoxic effect. TFPI mRNA level decreased after HUVECs were exposed to IL-6(0.5 ng/ml) from 6 h(P<0.05). TFPI mRNA level reached the lowest in 6 h(TFPI mRNA/GAPDH mRNA= 0.191), then gradually restored to the normal level till 48 h(TFPI mRNA/GAPDH mRNA=0.399). Conclusion: IL-6 at 0.1- 0.5 ng/ml does not show signs of cell toxicity, but it can inhibit the expression of TFPI mRNA. The decrease of TFPI mRNA expression in HUVECs induced by IL-6 may play an important role in the modulation of coagulation processes in blood circulation and coagulantion system change during the acute inflammation period.