摘要
目的探究补体1q/肿瘤坏死因子相关蛋白9(CTRP9)对减轻急性心肌梗死(AMI)后心肌组织纤维化的作用及其机制。方法构建小鼠AMI模型,使用超声机检测左心室射血分数(LVEF)评估心脏功能,应用免疫荧光染色检测α-SMA/Vimentin双染阳性细胞、心肌组织不同区域CTRP9表达情况,应用ELISA试剂盒检测小鼠血清CTRP9、转化生长因子(TGF)-β1含量,通过Masson染色检测小鼠心肌纤维化情况,Western Blotting检测心肌组织胶原蛋白Ⅰ、TGF-β1、蛋白激酶A(PKA)、p-PKA表达情况。结果小鼠AMI后第4天,血清CTRP9水平减低(P<0.001)、TGF-β1水平升高(P<0.001);AMI后第28天,LVEF显著减低(P<0.001),心肌纤维化明显增加(P<0.001),心肌组织TGF-β1水平明显升高(P=0.0025),肌成纤维细胞数量大量增加(P<0.001),PKA活性增强(P=0.0023),胶原蛋白Ⅰ表达明显增加(P=0.0238);敲除CTRP9小鼠AMI组(10/22)较野生型小鼠AMI组(10/27)死亡率增加,但生存曲线未达到统计学差异,心脏收缩功能进一步减低(P=0.0010),心肌纤维化更加严重(P=0.0395),PKA活性受到部分抑制(P=0.0063),TGF-β1(P=0.0126)、胶原蛋白Ⅰ(P=0.0090)表达增加更多;补充rCTRP9后,AMI组小鼠死亡明显减少,但生存曲线未达到统计学差异;心脏收缩功能明显改善(P<0.001);心肌纤维化明显减轻(P<0.001);PKA活性升高(P<0.001),TGF-β1(P<0.01)、胶原蛋白Ⅰ表达减少(P<0.01),应用PKA抑制剂H-89阻断后,CTRP9的心肌保护作用被阻断。结论CTRP9通过PKA通路明显减轻AMI小鼠心肌组织纤维化和改善心脏功能。
Objective To investigate the effect and molecular mechanism of complement 1q/tumor necrosis factor related pro⁃tein 9(CTRP9)on reducing myocardial fibrosis after acute myocardial infarction(AMI).Methods AMI-injured mouse model was established and the left ventricular ejection fraction(LVEF)was measured to assess cardiac function by ultrasound.α-SMA/vimentin double staining positive cells and the expression of CTRP9 in different regions of myocardium was detected by immunofluorescence stai⁃ning.The content of serum CTRP9 and TGF-β1 in mice was detected by ELISA kit,and the myocardial fibrosis was detected by Mas⁃son staining.The expression of Collagen I,TGF-1,PKA and p-PKA in myocardial tissue was detected by Western Blotting.Results On the fourth day after AMI,serum CTRP9 levels decreased(P<0.001)and TGF-β1 levels increased(P<0.001).On the 28th day after AMI,the LVEF decreased(P<0.001),myocardial fibrosis increased(P<0.001),TGF-β1 level in myocardium in⁃creased(P=0.0025),the number of myofibroblasts increased(P<0.001),the PKA activity increased(P=0.0023),and the expression of collagen I increased(P=0.0238).Compared with WT-MI+Vehicle group(10/27),the mortality rate of KO-MI+Vehicle group(10/22)increased,but the survival curve did not reach statistical difference.The cardiac contractile function further re⁃duced(P=0.0010),myocardial fibrosis was more severe(P=0.0395),PKA activity was partially inhibited(P=0.0063),TGF-β1(P=0.0126)and collagen I expression increased more(P=0.0090);After rCTRP9 supplementation,the death of mice in AMI group decreased significantly,but the survival curve did not reach statistical difference;the cardiac contractile function was signif⁃icantly improved(P<0.001);myocardial fibrosis was significantly reduced(P<0.001);PKA activity increased(P<0.001),TGF-β1(P<0.01)and collagen I expression decreased(P<0.01).However,the myocardial protective effect of CTRP9 was blocked af⁃ter treated with PKA inhibitor H-89.Conclusion CTRP9 significantly ameliorates myocardial fibrosis an
作者
李香敏
谭延振
张冰
赵荣
易定华
孙阳
易蔚
张平
Li Xiangmin;Tan Yanzhen;Zhang Bing;Zhao Rong;Yi Dinghua;Sun Yang;Yi Wei;Zhang Ping(Department of Cardiovascular Surgery,the First Affiliated Hospital,Air Force Medical University,Shaanxi Xi'an 710032,China)
出处
《中国体外循环杂志》
2021年第6期364-371,共8页
Chinese Journal of Extracorporeal Circulation
