肺微血管内皮细胞IL-8的表达及NF-κB调控机制的研究

An research on the expression of IL-8 in PMVEC and its mechanism through the Nuclear Factor-Kappa B

目的探讨脂多糖(LPS)的直接诱导作用对肺微血管内皮细胞(PMVEC)IL-8表达的影响及通过核因子κB(NF-κB)的调控机制。方法以100ng/ml LPS刺激PMVEC 0、0.5、1、2、4、6、8h或1ng/ml、10ng/ml1、00ng/ml LPS刺激1h或6h为检测时相点,ELISA、原位杂交试验分别检测的培养液上清中分泌的IL-8及PMVEC内IL-8mRNA的表达;凝胶电泳迁移率分析(EMSA)检测NF-κB的活化;并观察NF-κB活化抑制对IL-8表达的影响。结果LPS能显著促进PMVEC表达IL-8,包括促进IL-8mRNA的表达及IL-8的分泌。在时间上mRNA的表达先于IL-8分泌。且LPS的直接诱导能迅速活化NF-κB,1h达到高峰,后逐渐下降。PDTC能显著抑制NF-κB的活化及IL-8的表达(P<0.01)。结论表明细菌致病因子LPS的直接诱导确能通过促进NF-κB的活化,从而启动IL-8的高效表达和分泌,为多形核中性粒细胞(PMN)的迁移提供必需的物质条件,导致肺损伤。

Objective To study IL-8 expression of pulmonary microvascular endothelial cells （PMVEC） directly induced by LPS and its mechanism through the Nuclear Factor-Kappa B. Methods When PMVEC is directly excited by 100ng/ml LPS at 0h,0.5h, 1h,2h,4h,6h,8h or 1ng/ml, 10ng/ml, 100ng/ml LPS at lh or 6h,tbe expressions of IL-8mRNA in PMVEC and its protein secretion in the supematant of culture medium were examined by the methods of ISH, ELISA respectively and the activation of NF-κB was detected by EMSA. And those were then to be compared with which was inhibited by PDTC. Results LPS could directly act on the PMVEC to promote the IL-8 expression, including promoting the expression of IL-8mRNA and secretion of IL-8 protein, and the mRNA expressions increased before the protein secreted in terms of time.Tbe LPS excitement could also significantly promote the activation of NF-κB, which peaked at 1h and then went down. PDTC could significantly decrease the expression of IL-8 and the activation of NF-κB. Conclusion The directly-induction of L.PS could exactly promote the activation of NF-κB, then cause to the expression and secretion of IL-8. So as to provide the required physical condition for the PMN migration. It could be an important role in inflammatory response induced by LPS.