高表达血管紧张素转化酶2的内皮祖细胞降低野百合碱诱导的大鼠肺动脉高压

Endothelial progenitor cells with overexpressing angiotensin-converting enzyme 2 reduce monocrotaline-induced pulmonary arterial hypertension in rats

目的探讨高表达血管紧张素转化酶2(ACE2)基因的内皮祖细胞(EPCs)对肺动脉高压(PAH)大鼠的干预作用。方法体外分离大鼠骨髓EPCs并对其进行鉴定;用携带ACE2基因的慢病毒载体感染EPCs,检测感染前后EPCs中ACE2蛋白的表达及其增殖、成管功能的变化。将大鼠随机分为对照组(control组)、肺动脉高压组(PAH组)、内皮祖细胞治疗组(EPCs组)以及感染ACE2的内皮祖细胞治疗组(lenti-ACE2-EPCs组)。用野百合碱诱导肺动脉高压大鼠模型,3周后测定平均肺动脉压力(m PAP)、右心室肥厚指数(RV/LV+S)。肺组织HE染色,观察肺小动脉分布及炎性浸润,计算管壁厚度指数(TI)、面积指数(AI)。Western blot检测肺组织中ACE2蛋白表达。结果干预3周后,PAH组的m PAP、RV/LV+S、TI及AI均较对照组有显著上升(P<0.01);lenti-ACE2-EPCs组的m PAP、RV/LV+S、TI及AI则较PAH组、EPCs组水平有显著下降(P<0.01);lenti-ACE2-EPCs组大鼠肺组织中ACE2蛋白表达水平较PAH组明显增加(P<0.01)。造模3周后,EPCs组的m PAP、RV/LV+S、TI及AI均较PAH组有明显下降(P<0.01),但与对照组及lenti-ACE2-EPCs组比较则均明显升高(P<0.01)。结论高表达ACE2基因的大鼠内皮祖细胞能有效降低肺动脉高压大鼠肺动脉压力,且其治疗作用优于内皮祖细胞。

Objective To investigate the therapeutic effect of endothelial progenitor cells（ EPCs） with overexpressed angiotensin converting enzyme 2（ ACE2） on rat model of monocrotaline（ MCT） induced pulmonary arterial hypertension（ PAH）. Methods EPCs were extracted,purified and identified from the very beginning. The lentivirus vector carrying ACE2 gene was infected with EPCs in order to prepare the ACE2-EPCs. Besides,the expression of ACE2 and proliferation as well as tube function of EPCs were detected before and after the transduction. The SD rat were randomly divided into control group,MCT induced pulmonary arterial hypertension group（ PAH group）,ACE2 transduction of endothelial progenitor cells group（ lenti-ACE2-EPCs group） and endothelial progenitorcells group（ EPCs group）. The mean pulmonary artery pressure of rats（ m PAP） and right ventricular hypertrophy index（ RV/LV＋S） were determined in third week after the molding; the lung tissue specimens were stained with HE and the pulmonary arterial wall thickness index（ TI） as well as area index（ AI） were also calculated; The expression levels of ACE2 in lung tissue were detected by Western blot. Results The m PAP,RV/LV＋S,TI and AI detected in PAH group in the third week after the molding were signficantly lower than those in control group（ P〈0. 01）; The m PAP,RV/LV＋S,TI and AI detected in lenti-ACE2-EPCs group in the third week after the molding were markedly lower than those in PAH group and EPCs group（ P 0. 01）; The expression level of ACE2 in lung tissue of lentiACE2-EPCs group was significantly higher than that in PAH group（ P〈0. 01）; The m PAP,RV/LV＋S,TI and AI detected in EPCs group in the third week after the molding were markedly lower than those in PAH group（ P〈0. 01）,while higher than that as compared with control group and lenti-ACE2-EPCs group（ P〈0. 01）. Conclusions ACE2 overexpression in endothelial progenitor cells（ EPCs） can effectively reduce the mean pulmonary arterial pressure in PAH rat models,and the therapeutic effect of ACE2-EPCs is generally better than that of EPCs.