基质金属蛋白酶参与心力衰竭患者心肌细胞外基质的调控

目的探讨基质金属蛋白酶家族(MMP)-2、3、9,细胞外基质(ECM)纤连蛋白(FN)和肌腱蛋白(TN-C)与心衰患者心肌重构、心功能损害的关系。方法选择因二尖瓣关闭不全心脏病接受二尖瓣置换术的充血性心力衰竭(CHF)患者39例,正常对照38例(其中8例来自意外伤亡的器官捐献者)。酶联免疫吸附实验(ELISA)检测CHF患者及正常对照组血清MMP-2、3、9及其抑制物-1(TIMP-1)水平,光镜检测心肌组织病理变化,免疫沉淀法检测心肌组织MMP-2、3、9及TIMP-1蛋白质表达,免疫荧光法检测心肌组织细胞外基质FN、TN-C的分布。结果瓣膜病所致CHF患者心肌组织呈典型的心肌重构病理改变。正常对照组血浆MMP-2、3、9及TIMP-1水平分别为213μg/L±23μg/L、485μg/L±102μg/L、158μg/L±31μg/L、208μg/L±15μg/L,各CHF组心功能Ⅱ级组(276μg/L±18μg/L、613μg/L±118μg/L、245μg/L±43μg/L、126μg/L±12μg/L),心功能Ⅲ级组(302μg/L±20μg/L、850μg/L±132μg/L、310μg/L±39μg/L、83μg/L±11μg/L),心功能Ⅳ级组(367μg/L±15μg/L、998μg/L±99μg/L、392μg/L±27μg/L、61μg/L±12μg/L),与正常对照组比较差异有统计学意义(P<0.05或0.01)。心肌组织MMP-2、3、9及TN-C蛋白质表达吸光度值(A)(A/β-肌动蛋白)比值正常对照组分别为1.01±0.02、1.45±0.04、0.68±0.03、0,各CHF组心功能Ⅱ级组(1.13±0.01、1.69±0.05、1.32±0.05、1.69±0.05),心功能Ⅲ级组(3.32±0.02、1.98±0.06、1.73±0.07、1.89±0.06),心功能Ⅳ级组(6.29±0.05、2.36±0.4、1.99±0.09、3.36±0.40),与正常对照组比较差异有统计学意义(P<0.05或0.01);相反,心肌组织TIMP-1、FN蛋白质表达(A/β-肌动蛋白)比值,正常组分别为2.10±0.12、2.01±0.02,各CHF组心功能Ⅱ级组(1.58±0.16、1.13±0.01),心功能Ⅲ级组(0.79±0.06、0.70±0.02),心功能Ⅳ级组(2.10±0.12、0.42±0.05),与正常对照组比较差异有统计学意义(P<0.05或0.01)。结论心衰患者MMP-2、3、9表达量的增高及TIMP-1的降低参与心肌重构的病理过程,通过改变心肌细胞外基质进一步恶化心功能。

Involvement of matrix metalloproteinases in the regulation of myocardial extracellular matrix in patients with congestive heart failure

OBJECTIVE: To investigate the expression of the matrix metalloproteinases (MMP)-2, -3, and 9, tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), fibronectin (FN), and tenascin-C (TN-C) in the myocardium, and their relationship with the myocardial remodeling and heart function in the patients with congestive heart failure (CHF). METHODS: A few tissues of papillary muscles of left ventricle were taken from 39 patients with mitral insufficiency during mitral valve replacement, and from 8 organ donors who had died of accidents to undergo pathological examination and to detect the protein expression of MMP-2, -3, and 9, and TIMP-1 by immunoprecipitation and the expression of FN and TN-C by immunofluorescence test. Peripheral blood samples were collected from these 39 patients and 30 normal controls to examine the plasma MMPs and TIMP-1 by ELISA. RESULTS: Typical myocardial remodeling was seen in the myocardial tissues of the CHF patients. The plasma levels of MMP-2, -3, and -9 of the CHF patients in the cardiac function classes II - IV were all significantly higher than those of the normal controls (P < 0.05 or P < 0.01) with a tendency to increase with the deterioration of heart function, The plasma level of TIMP-1 of the CHF patients in the cardiac function classes II - IV were all significantly higher than that of the normal controls (P < 0.05 or P < 0.01) with a tendency to decrease with the deterioration of heart function. The protein expression levels of MMP-2, -3, and -9 in the myocardium of the CHF patients in the cardiac function classes III - IV were all significantly higher than those of the normal controls (P < 0.05 or P < 0.01) with a tendency to increase with the deterioration of heart function. The protein expression levels of TIMP-1 in the myocardium of the CHF patients in the cardiac function classes III - IV were all significantly lower than that of the normal controls (P < 0.05 or P < 0.01) with a tendency to decrease with the deterioration of heart function. The protein expression levels of FN in the myocardium of the CHF patients in the cardiac function classes II - IV were all significantly lower than that of the normal controls (all P < 0.05) with a tendency to decrease with the deterioration of heart function. The protein expression levels of TN-C in the myocardium of the CHF patients in the cardiac function classes II - IV were all significantly higher than that of the normal controls (all P < 0.01) with a tendency to increase with the deterioration of heart function. CONCLUSION: The increasing expression of MMP-2, -3, and -9 and the decreasing expression of TIMP-1 contribute to the myocardial remodeling, thus changing the extracellular matrix in the myocardium tissue and leading to the development and progression of CHF.