钙卫蛋白、TLR-4及MAPK信号转导途径在动脉血栓形成过程中与COX-2的关系
Correlation between calprotectin, TLR-4, and MAPK signal transduction pathways and COX-2 in the process of arterial thrombosis

目的 探索钙卫蛋白（S100A8/A9）、Toll样受体4（TLR-4）及丝裂原活性的蛋白激酶（MAPK）信号传导途径在动脉血栓中的表达及与环氧化酶-2（COX-2）的关系。方法 24只SD大鼠分为实验组和对照组，实验组利用FeCl3溶液建立颈动脉血栓大鼠模型，对照组注射等量生理盐水。分别于造模后第1、3、7、14日分批处死2组大鼠，每次每组3只。利用ELISA检测大鼠外周血S100A8/A9水平。采用Western blotting对SD大鼠外周血白细胞中COX-2、p-p38 MAPK、TLR-4水平进行检测，并分析各因子水平之间的相关性。利用MAPK抑制剂SB203580对模型大鼠进行干预，观察对COX-2蛋白水平的影响。 结果 实验组大鼠外周血S100A8/A9水平在造模后第7日达到最高值，第14日回落，且均显著高于对照组相应时间点水平（P<0.05）。外周血白细胞中TLR-4、p-p38 MAPK、COX-2的表达水平随造模后时间的推移逐渐升高，第14日达到最高值。其中TLR-4与COX-2之间相关性较好（r=0.831，P=0.012）。模型大鼠经MAPK抑制剂干预后，COX-2蛋白水平显著降低。结论 S100A8/A9可能主要参与动脉形成早期炎症反应过程，COX-2与TLR-4在蛋白水平的表达具有一定相关性。动脉血栓形成初期COX-2表达升高可能与体内高水平S100A8/A9激活TLR-4/p38 MAPK信号途径调节有关。
： Objective To investigate calprotectin (S100A8/A9), Toll-like receptor 4 (TLR-4), and mitogen-activity of protein kinase (MAPK) signaling pathways in the arteries thrombosis and their correlation with cyclooxygenase-2 (COX-2). Methods Twenty-four SD rats were assigned to the experiment group and the control group. A rat model of carotid artery thrombosis was constructed in the experiment group by using FeCl3 solution. The same volume of normal saline was injected in the control group. Rats were sacrificed at the 1st, 3rd, 7th, and 14th day after the model was constructed and 3 rats per group were sacrificed each time. S100A8/A9 level in peripheral blood was measured by ELISA. Western blotting was used to detect COX-2, p-p38 MAPK, and TLR-4 levels in peripheral blood leukocytes. Then the correlation between these factors was analyzed. MAPK inhibitor SB203580 was used to intervene the rat model and the effects on COX-2 protein level was observed. Results For the experiment group, the S100A8/A9 level in rat peripheral blood reached the peak at the 7th day after the model was constructed, fell at the 14th day, and was significantly higher as compared with the control group at corresponding time points (P<0.05). The expressions of TLR-4, p-p38 MAPK, and COX-2 in peripheral blood leukocytes increased with time after the model was constructed and reached peak at the 14th day. The correlation between TLR-4 and COX-2 was close (r=0.831, P=0.012). After intervention with MAPK inhibitors, the protein level of COX-2 significantly reduced. Conclusion S100A8/A9 may mainly participate in the early inflammation response process in arteriogenesis. COX-2 has a certain correlation with TLR-4 in terms of protein expression. At the early stage of arterial thrombosis, elevated COX-2 expression may be associated with TLR-4/p38 MAPK signaling pathway activated by high level of S100A8/A9