CXCR4在溃疡性结肠炎小鼠蛋白C系统变化中的作用  

Role of CXCR4 in changes of protein C system in ulcerative colitis mice

作　　者：林旭红[1] 王丹丹[2] 王慧超[3] 李玉霞[1] 杨瑞林[1] 

机构地区：[1]河南大学淮河医院检验科,转化医学中心,河南开封475000 [2]河南大学医学院,淮河医院心内科,河南开封475000 [3]河南大学第一附属医院肾内科,河南开封475000

出　　处：《中国病理生理杂志》2016年第10期1854-1862,共9页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.U1304802;No.81500430)

摘　　要：目的:蛋白C系统(PCS)是血管内皮功能重要的介导者,而微血管内皮细胞是参与溃疡性结肠炎(UC)最重要的非免疫细胞,本研究旨在探讨趋化因子受体CXCR4在UC病理过程中PCS变化的作用。方法:动物实验分为对照组和UC模型组,进行大体积分、组织病理学积分及溃疡指数评估;测定各组结肠组织和血浆中髓过氧化物酶(MPO)、环氧合酶-2(COX-2)、基质细胞衍生因子-1α(SDF-1α)和单核细胞趋化蛋白-1(MCP-1)的mRNA水平及活性;检测各组结肠CXCR4、β-arrestin、p-JNK、内皮细胞蛋白C受体(EPCR)和血栓调节蛋白(TM)的水平及分布;观察蛋白C(PC)和蛋白S(PS)的活性。分离、培养、鉴定结肠微血管内皮细胞,分为对照组、SDF-1α组、CXCR4沉默组和CXCR4过表达组,观察各组细胞EPCR、TM、β-arrestin和p-JNK的蛋白水平,以及PC、PS和激活的蛋白C(APC)活性。结果:与对照组比,模型组小鼠大体积分、组织病理学积分及溃疡指数升高(P<0.05)。结肠组织和血浆MPO、COX-2、SDF-1α和MCP-1 mRNA水平和活性显著升高(P<0.01)。结肠组织CXCR4、β-arrestin和p-JNK的蛋白水平上调,EPCR表达下调,血浆PC和PS活性明显降低(P<0.05或P<0.01)。CXCR4过表达进一步加重SDF-1α对结肠黏膜微血管内皮细胞PCS的抑制,同时进一步升高β-arrestin和p-JNK的蛋白水平(P<0.05)。结论:UC时PCS被抑制,CXCR4参与其中,其可能的机制是CXCR4在UC病理过程中介导趋化因子通过β-arrestin-JNK信号通路进一步影响血管内皮细胞功能,从而抑制PCS。AIM： To explore the role of chemokine receptor CXCR 4 in the pathogenesis of protein C system （PCS） in ulcerative colitis （UC）.METHODS：In vivo, the mice were divided into control group and UC group .The macroscopic score, microscopic score and ulcer index were assessed .The mRNA levels and activity of myeloperoxidase （ MPO） , cyclooxygenase-2 （ COX-2 ） , stromal cell-derived factor-1α（ SDF-1α） and monocyte chemotactic protein 1 （MCP-1） both in colonic tissue and plasma were determined .The expression and location of CXCR4,β-arrestin, p-JNK, endothelial cell protein C receptor （EPCR） and thrombomodulin （TM） were detected.The activity of protein C （PC） and protein S （ PS） was measured in each group .In vitro, mouse colonic microvascular endothelial cells were isolated , cultured and identified.Both CXCR4-overexpressing and CXCR4-silencing colonic mucosa microvascular endothelial cells were constructed.The effects of SDF-1αon the protein levels of EPCR , TM,β-arrestin and p-JNK, and on the activity of PC , PS and activated protein C （ APC） were observed .RESULTS：Compared with control group , UC mice showed increased gross score, histopathological score and ulcer index （P〈0.05）.The mRNA levels and activity of MPO, COX-2, SDF-1αand MCP-1 in colon and plasma were increased （P〈0.01）.The protein levels of CXCR4,β-arrestin and p-JNK were up-regu-lated, EPCR expression was down-regulated in colon, and the activity of PC and PS in plasma was decreased （P〈0.05 or P〈0.01）.CXCR4 overexpression further aggravated SDF-1α-induced PCS inhibition in colonic mucosa microvascular en-dothelial cells, and further up-regulated the protein levels of β-arrestin and p-JNK （P〈0.05）.CONCLUSION：PCS is inhibited in UC.CXCR4 is involved in the regulation of PCS inhibition by mediating chemokines and acting on colonic mucosa microvascular endothelial cells through β-arrestin-JNK pathway .

关 键 词：CXCR4 溃疡性结肠炎 蛋白C系统 血栓形成 

分 类 号：R363.2[医药卫生—病理学]