中华急诊医学杂志  2025, Vol. 34 Issue (9): 1222-1228   DOI: 10.3760/cma.j.cn114656-20240919-00652
血管紧张素转换酶2和卡托普利对机械通气相关性肺损伤小鼠的影响及作用机制
许俊平 , 陈霖 , 余天兴 , 张学平 , 谢万 , 张耿 , 林新     
福州市第一总医院呼吸与危重症医学科,福州 350009
摘要: 目的 探讨血管紧张素转换酶2(angiotensin-converting enzyme 2, ACE2)和卡托普利(Captopril, CAP)对机械通气肺损伤小鼠的影响及作用机制。方法 72只健康雄性BALB/C小鼠随机(随机数字法)分为正常对照组(normal control group, NC组)、机械通气相关性肺损伤(ventilator induced lung injury, VILI)组、ACE2组、VILI+ACE2组、CAP组、VILI+CAP组,每组12只。于机械通气前1 h,ACE2组和VILI+ACE2组腹腔内注射ACE2 0.1 mg/kg,CAP组和VILI+CAP组腹腔注射卡托普利2.5 mg/kg。机械通气结束后,取血清,ELISA检测炎症因子[血小板活化因子(platelet activating factor, PAF)、内皮素1(endothelin-1, ET-1)、可溶性细胞间粘附分子1(soluble intercellular adhesion molecule-1, sICAM-1)、前列腺素E2(Prostaglandin E2, PGE2)]和心血管系统相关指标[小鼠血管性血友病因子(von willebrand factor, vWF)、血栓调节蛋白(thrombomodulin, TM)、血管紧张素(angiotensin, Ang)(1-9)、Ang(1-7)、前列环素I 2(prostacyclin I 2, PGI2)]。取肺泡灌洗液,BCA法检测总蛋白浓度,ELISA法检测sICAM-1的水平;取肺组织,采用苏木素-伊红染色检测肺脏病理损伤并进行肺损伤评分,Western Blot法、RT-qPCR分别检测ACE2蛋白、mRNA的相对表达量。用IBM SPSS 20.0软件进行统计学分析,组间比较采用单因素方差分析和LSD法。结果 ACE2、CAP组小鼠血清、肺组织中PAF、ET-1、sICAM-1、vWF、TM、Ang(1-9)、Ang(1-7)、PGI2的水平与NC组相比,差异均无统计学意义(均P > 0.05)。与VILI组相比较,VILI+ACE2和VILI+CAP组小鼠血清、肺组织中的PAF、ET-1、sICAM-1、vWF水平均降低(均P < 0.05),TM、Ang(1-9)、Ang(1-7)、PGI2的水平均增加(均P < 0.05),肺损伤减轻,肺组织的湿干比降低(均P < 0.05),且ACE2的蛋白和mRNA的表达量增加(均P < 0.05)。结论 ACE2和CAP均可以抑制炎症、保护心血管系统,可能是通过ACE2/Ang(1-9)/Ang(1-7)轴的作用,发挥对VILI的保护作用。
关键词: 机械通气相关性肺损伤    血管紧张素转换酶2    卡托普利    肺损伤    血管紧张素    
The effects and mechanisms of angiotensin-converting enzyme 2 and Captopril on mechanically ventilated lung injury in mice
Xu Junping , Chen Lin , Yu Tianxing , Zhang Xueping , Xie Wan , Zhang Geng , Lin Xin     
Department of Respiratory and Critical Care Medicine, Fuzhou First General Hospital, Fuzhou 350009, China
Abstract: Objective To investigate the effects and mechanisms of angiotensin-converting enzyme 2 (ACE2) and Captopril (CAP) on mechanical ventilation-induced lung injury (VILI) in mice. Methods Seventy-two healthy male BALB/c mice were randomly assigned (using a random number table) into six groups (n=12 per group): normal control (NC) group, VILI group, ACE2 group, VILI+ACE2 group, CAP group, and VILI+CAP group. One hour prior to mechanical ventilation, the ACE2 and VILI+ACE2 groups were intraperitoneally injected with ACE2 at a dose of 0.1 mg/kg, while the CAP and VILI+CAP groups were intraperitoneally injected with CAP at a dose of 2.5 mg/kg. Following mechanical ventilation, serum samples were collected and enzyme-linked immunosorbent assay (ELISA) was used to detect inflammatory factors [platelet activating factor (PAF), endothelin-1 (ET-1), soluble intercellular adhesion molecule-1 (sICAM-1), prostaglandin E2 (PGE2)] and cardiovascular system related indicators [von Willebrand factor (vWF), thrombomodulin (TM), angiotensin (Ang) (1-9), Ang (1-7), prostacyclin I 2 (PGI2)]. Bronchoalveolar lavage fluid (BALF) was gathered, and total protein concentration was determined using BCA method, and sICAM-1 levels were measured by ELISA. Lung tissues were collected and subjected to hematoxylin and eosin staining (HE staining) for the assessment of pathological lung injury and lung injury scoring. Western blot and reverse transcription quantitative polymerase chain reaction (RT-qPCR) were utilized to detect the relative expression levels of ACE2 protein and mRNA, respectively. Statistical analysis was performed using IBM SPSS 20.0 software. Intergroup comparisons were conducted using one-way analysis of variance followed by the least significant difference (LSD) test. Results No statistically significant differences were observed in the levels of PAF, ET-1, sICAM-1, vWF, TM, Ang(1-9), Ang(1-7), and PGI2 in serum and lung tissues between the ACE2/CAP groups and the NC group (all P > 0.05). Compared with the VILI group, the VILI+ACE2 and VILI+CAP groups exhibited significantly decreased serum and lung tissue levels of PAF, ET-1, sICAM-1, and vWF (all P < 0.05), while the levels of TM, Ang(1-9), Ang(1-7), and PGI2 were significantly increased (all P < 0.05). Pathological lung injury was alleviated, and the lung wet/dry weight ratio was significantly reduced (all P < 0.05) in the VILI+ACE2 and VILI+CAP groups. Furthermore, both ACE2 protein and mRNA expression levels were significantly increased in these groups (all P < 0.05). Conclusion Both ACE2 and CAP can inhibit inflammation and protect the cardiovascular system, possibly by promoting the ACE2/Ang(1-9)/Ang(1-7) axis, thereby exerting a protective effect against VILI.
Key words: Mechanical ventilation-induced lung injury    Angiotensin-converting enzyme 2    Captopril    Lung Injury    Angiotensin    

急性肺损伤(acute lung injury, ALI)及其重症形式急性呼吸窘迫综合征(acute respiratory distress syndrome, ARDS)为严重临床危象,机械通气虽为治疗核心,但不当设置可诱发气压伤、容积伤及肺组织周期性损伤,激发炎症反应、补体激活与氧化应激,增强肺毛细血管通透性及促凝血,加剧肺损伤病理过程,形成机械通气相关性肺损伤(ventilator induced lung injury,VILI),威胁患者氧合与肺功能[1]

血管紧张素转化酶2(angiotensin-convertion enzyme 2, ACE2),系血管紧张素转换酶(angiotensin convertion enzyme, ACE)的同系物,血管紧张素(angiotensin, Ang)Ⅰ和Ang Ⅱ可分别在ACE2的作用下转化为Ang(1-9)、Ang(1-7),从而在肾素-血管紧张素系统(renin-angiotensin system, RAS)中发挥关键的抑制作用[2-3]。卡托普利(Captopril, CAP),作为一种经典的血管紧张素转化酶抑制剂(angiotensin converting enzyme inhibitor, ACEI),在心血管疾病的治疗中发挥着重要作用,其核心作用机制在于特异性地抑制体内ACE的催化活性,这一抑制效应显著减少AngⅠ向具有强烈缩血管及促增殖作用的AngⅡ的生物转化过程,可以抑制缓激肽降解酶的活性,促进血液中缓激肽水平的提升,进而对心血管系统起到保护作用[4]。研究显示ACE2/Ang(1-7)、ACE2/Ang(1-9)轴对肺、肾具有保护作用,减轻肺纤维化程度[5-7]。因此本研究探讨ACE2和CAP是否通过调控ACE2/Ang(1-7)/Ang(1-9)轴,发挥抗炎、改善内皮屏障等作用,减轻VILI。

1 材料与方法 1.1 实验动物

本研究对象为72只体重18~22 g的SPF级4~6周龄雄性BALB/C小鼠,动物许可证号:SCXK(湘)2019-0004,购自湖南斯莱克景达实验有限公司。本研究经福建医科大学动物伦理委员会批准,批准号:IACUC FJMU 2023-Y-0438。12 h人工日光灯管照射,光照强度维持在200 Lux,室内环境温度调控在(23±1)℃的范围内,相对湿度保持在50%~80%,小鼠自由饮水和进食。

1.2 主要试剂及仪器

小鼠血管性血友病因子(von willebrand factor,vWF)、内皮素1(Endothelin-1,ET-1)、可溶性细胞间粘附分子1(soluble intercellular adhesion molecule-1,sICAM-1)、血栓调节蛋白(thrombomodulin,TM)、血小板活化因子(platelet activating factor,PAF)、Ang(1-9)、Ang(1-7)、前列环素(prostacyclin,PG)I2、PGE2 ELISA检测试剂盒均购自上海酶联生物技术有限公司;兔ACE2多克隆抗体、鼠GAPDH单克隆抗体、辣根过氧化酶标记羊抗体兔IgG、辣根过氧化酶标记羊抗体鼠IgG购自成都正能生物技术有限责任公司;Genious 2X SYBR Green Fast qPCR Mix购自武汉爱博泰克生物科技有限公司;卡托普利购自上海麦克林生化科技有限公司。TransZol Up Plus RNA Kit和TransScript® All-in-One First-Strand cDNA Synthesis SuperMix for qPCR(One-Step gDNA Removal)购自北京全式金生物技术股份有限公司。

主要仪器包括:化学发光仪购自上海勤翔科学仪器有限公司;KW-10小动物人工呼吸机购自南京卡尔文生物科技有限公司;荧光定量PCR仪和微量紫外-可见光分光光度计购自赛默飞世尔科技(中国)有限公司。

1.3 方法 1.3.1 模型建立及分组

适应性喂养一周后,按照随机数字法把BALB/C小鼠分为6组,即正常对照组(normal control group,NC组)、VILI组、ACE2组、VILI+ACE2组、CAP组、VILI+CAP组,每组12只。腹腔内注射5%水合氯醛麻醉后,制备VILI模型采用大潮气量机械通气的方法[4]:仰卧位固定,颈部备皮、常规消毒,经口插管并连接呼吸机,设置潮气量为20 mL/kg,呼吸频率为60次/min,小鼠机械通气时间均为4 h。ACE2和CAP溶解于PBS液中,于机械通气前1 h,ACE2组和VILI+ACE2组腹腔内注射ACE2 0.1 mg/kg,CAP组和VILI+CAP组腹腔注射卡托普利2.5 mg/kg。NC组保留自主呼吸室内空气。

1.3.2 检测血清中血清vWF、ET-1、sICAM-1、TM、PAF、Ang(1-9)、Ang(1-7)、PGI2、PGE2的含量

机械通气达到预定时间后,行心室内采血。在无菌环境中下,用组织剪开胸,使心脏和肺组织暴露,于心尖部采血,并快速分离血清于-80℃保存。使用ELISA试剂盒检测血清中vWF、ET-1、sICAM-1、TM、PAF、Ang(1-9)、Ang(1-7)、PGI2、PGE2的含量,严格按照说明书进行检测。

1.3.3 肺泡灌洗液中sICAM-1和总蛋白浓度的检测

动物实验中,小鼠机械通气结束后,行支气管肺泡灌洗。参考郭君平等[8]的实验方法,收集小鼠支气管肺泡灌洗液(Bronchoalveolar lavage fluid, BALF)。用1 mL生理盐水灌洗气管3次,将灌洗液于4℃,3 000 g,离心10 min,上清液于-80℃冻存。使用ELISA试剂盒检测BALF中sICAM-1的含量,BCA试剂盒检测BALF中总蛋白的浓度。

1.3.4 肺组织湿/干重比(wet to dry, W/D)

小鼠放血后取肺组织,每组取6只,滤吸干表面水分后,置于干净器皿内精确称量后,放于75℃恒温烤箱内,烘烤24 h至恒重后测定肺组织干重,计算W/D以评价肺组织水肿程度。

1.3.5 肺组织的苏木素-伊红染色(Hematoxylin and Eosin Staining, HE染色)及ELISA试剂盒检测指标

取小鼠右侧肺组织,用组织固定液固定,乙醇梯度脱水,二甲苯透明、浸蜡,包埋制成蜡块,切成5 μm切片,进行HE染色,光镜下观察肺组织学形态及进行肺损伤评分。整取左侧肺部于液氮中速冻,之后放-80℃冰箱保存待检。称取肺组织0.1 g,制备成10%的组织匀浆,根据ELISA试剂盒的说明书检测肺组织中vWF、ET-1、sICAM-1、TM、PAF、Ang(1-9)、Ang(1-7)、PGI2、PGE2的水平。

1.3.6 实时荧光定量PCR(reverse transcription quantitative polymerase chain reaction RT-Qpcr,RT-qPCR)检测小鼠肺组织ACE2的相对表达量

收集液氮速冻后的肺组织,使用RNA提取试剂盒提取总RNA,并根据反转录试剂盒的说明书进行反转录,得到cDNA。用稀释5倍的cDNA作为RT-qPCR的模板,使用ABI QuantStudio 3进行RT-qPCR。所用的引物序列为ACE2-F: 5'-GCAGATGGCTACAACTATAACCG-3',ACE2-R: 5'-CCTCCTCACATAGGCATGAAGA-3',GAPDH-F: 5'-TGGAAAGCTGTGGCGTGATG-3',GAPDH-R: 5'-TACTTGGCAGGTTTCTCCAGG-3';其中GAPDH作为内参基因。使用2-∆∆CT法计算结果。

1.3.7 Western blot测定ACE2蛋白的表达

取-80℃冻存的肺组织,加入含蛋白酶抑制剂的高效组织裂解液RIPA,冰上反复吹打,12 000 g离心10 min后,取上清液用BCA法测蛋白浓度,制备样本;样本经12% SDS-PAGE分离蛋白后,转至PVDF膜上,5% BSA室温封闭1 h后,分别使用抗体ACE2(1∶1 000)、GAPDH(1∶5 000),4℃孵育过夜,TBST洗膜三次,加入HRP标记的羊抗鼠二抗(1∶5 000)或羊抗兔二抗(1∶5 000),室温孵育1 h,TBST洗膜三次,加入ECL化学发光液显色、曝光、拍照。使用Image J软件分析目的蛋白的灰度值。

1.4 统计学方法

采用IBM SPSS 20.0统计软件进行数据分析。符合正态分布的计量资料以均数±标准差(x±s)表示,多组间比较采用单因素方差分析,进一步两两比较采用LSD法。以P < 0.05为差异有统计学意义。

2 结果 2.1 HE染色结果

NC、ACE2、CAP组肺脏实质为肺内支气管各级分支及其终末的大量肺泡,肺泡壁由单层上皮组成,间质包括肺内结缔组织及血管等,未见明显异常。与NC组比较,VILI组肺组织可见少量细支气管黏膜上皮细胞排列不规则,肺泡壁可见较多粒细胞浸润,肺泡大小不一,小范围肺泡壁毛细血管淤血;与VILI组相比,VILI+ACE1、VILI+CAP组肺损伤程度减轻,血管周围偶见散在的淋巴细胞浸润,少量血管淤血,肺泡壁可见少量粒细胞浸润,差异均有统计学意义(P < 0.05),见图 1A1B。与NC组比较,VILI、VILI+ACE2、VILI+CAP组中的W/D比NC组的增加(P < 0.05);与VILI组比较,VILI+ACE2、VILI+CAP组中的蛋白W/D均显著下降(P < 0.05)。NC组与ACE2、CAP组中的W/D差异无统计学意义(P > 0.05),见图 1C

注:A为肺组织病理改变(HE,×200);B为肺组织损伤评分;C为W/D比值;与NC组比较,aP < 0.05;与VILI组比较,bP < 0.05 图 1 各组小鼠肺组织病理学及W/D比值 Fig 1 Pathological changes and W/D ratio of lung tissues in mice of each group
2.2 BALF中总蛋白和sICAM-1的浓度

BCA法检测BALF中总蛋白和sICAM-1浓度,结果显示:与NC组比较,VILI、VILI+ACE2、VILI+CAP组中的总蛋白浓度均增加(P < 0.05);与VILI组比较,VILI+ACE2、VILI+CAP组中的总蛋白浓度均降低(P < 0.05),见图 2A。与NC组比较,VILI、VILI+ACE2、VILI+CAP组中的sICAM-1浓度均增加(P < 0.05);与VILI组比较,VILI+ACE2和VILI+CAP组中sICAM均降低(P < 0.05),见图 2B。AEC2、CAP组与NC组中的总蛋白、sICAM-1浓度均差异无统计学意义(P > 0.05)。

注:A为BALF中总蛋白的含量;B为BALF中sICAM-1的含量;与NC组比较,aP < 0.05;与VILI组比较,bP < 0.05 图 2 各组小鼠BALF中总蛋白和sICAM-1的浓度比较 Fig 2 Comparison of the concentrations of total protein and sICAM-1 in BALF of mice in each group
2.3 血清中PAF、ET-1、sICAM-1、PGE2、vWF、TM、Ang(1-9)、Ang(1-7)、PGI2的表达水平

与NC组比较,VILI、VILI+ACE2、VILI+CAP组血清中PAF、ET-1、sICAM-1、vWF含量增加(P < 0.05);与VILI组比较,VILI+ACE2和VILI+CAP组中PAF、ET-1、sICAM-1、vWF均下降(P < 0.05)见图 3A~E。VILI组中的TM、Ang(1-9)、Ang(1-7)、PGI2含量比NC组下降(P < 0.05);与VILI组比较,VILI+ACE2和VILI+CAP组中的TM、Ang(1-7)、Ang(1-9)、PGI2的含量均增加(P < 0.05),见图 3F~I。所检测的这些指标,ACE2组、CAP组与NC组间均差异无统计学意义(P > 0.05)。

注:与NC组比较,aP < 0.05;与VILI组比较,bP < 0.05 图 3 各组小鼠血清中PAF、ET-1、sICAM-1、PGE2、vWF、TM、Ang(1-9)、Ang(1-7)及PGI2的表达水平 Fig 3 Expression levels of PAF, ET-1, sICAM-1, PGE2, vWF, TM, Ang(1-9), Ang(1-7) and PGI2 in serum of mice in each group
2.4 肺组织中PAF、ET-1、sICAM-1、PGE2、vWF、TM、Ang(1-9)、Ang(1-7)、PGI2的表达水平

ELISA检测肺组织中PAF、ET-1、sICAM-1、PGE2、vWF、TM、Ang(1-9)、Ang(1-7)及PGI2的含量。结果显示:与NC组比较,VILI、VILI+ACE2、VILI+CAP组中PAF、ET-1、sICAM-1、vWF含量均增加(P < 0.05),VILI、VILI+ACE2组中PGE2的含量增加(P < 0.05),VILI+CAP组PGE2的含量差异无统计学意义(P > 0.05);与VILI组比较,VILI+ACE2和VILI+CAP组中PAF、ET-1、sICAM-1、PGE2、vWF均下降(P < 0.05),见图 4A~E。与NC组比较,VILI、VILI+ACE2、VILI+CAP组中的TM、Ang(1-9)、Ang(1-7)含量降低(P < 0.05),VILI组中PGI2含量降低(P < 0.05);与VILI比较,VILI+ACE2和VILI+CAP组中的TM、Ang(1-9)、Ang(1-7)、PGI2的含量均增加(P < 0.05),见图 4E~I。所检测的这些指标,ACE2、CAP与NC组间均差异无统计学意义(P > 0.05)。

注:与NC组比较,aP < 0.05;与VILI组比较,bP < 0.05 图 4 各组小鼠肺组织中PAF、ET-1、sICAM-1、PGE2、vWF、TM、Ang(1-9)、Ang(1-7)及PGI2的表达水平 Fig 4 Expression levels of PAF, ET-1, sICAM-1, PGE2, vWF, TM, Ang (1-9), Ang (1-7), and PGI2 in lung tissue of mice in each group
2.5 肺组织中ACE2蛋白和基因的表达水平

VILI组中ACE2蛋白和基因的水平都比NC组中的降低(P < 0.05),见图 5。和VILI比较,VILI+ACE2和VILI+CAP组中ACE2的蛋白和基因水平均增加(P < 0.05)。ACE2、CAP组与NC间差异无统计学意义(P > 0.05)。

注:A为Western blot检测ACE2蛋白的结果;B为ACE2蛋白的相对表达量;C为RT-qPCR检测ACE2 mRNA表达情况;与NC组比较,aP < 0.05;与VILI组比较,bP < 0.05 图 5 各组小鼠肺组织中ACE2蛋白和基因的表达水平 Fig 5 Expression levels of ACE2 protein and mRNA in lung tissue of mice in each group
3 讨论

ALI的主要症状是肺部出现剧烈的炎症反应,导致肺泡内皮屏障破坏、炎症细胞浸润,以及炎症和细胞毒介质的释放,肺泡上皮细胞和效应T细胞的活化[9]。大量炎症渗出使肺泡内充满富含蛋白质的液体,导致肺泡的呼吸功能受损,表面活性剂的合成和代谢受损进一步破坏患者的呼吸功能[10]。因大量炎症因子的破坏,肺组织的氧化与抗氧化之间的平衡也会遭到破坏[11]。本研究显示,腹腔注射ACE2或CAP,VILI小鼠肺组织和血清中炎症指标降低,心血管系统指标及肺组织病理形态有所改善,进一步促进肺功能的恢复。Xia等[12]和Boskabadi等[13]对ALI小鼠的研究结果表明,ACE2、CAP的促肺功能恢复作用被证实。

炎症是诱发肺部病理生理变化的关键因素[14]。研究表明炎症因子PAF[15]、ET-1[16]、sICAM-1[17]、PGE2[18]的水平与肺损伤密切相关。本实验结果显示,VILI小鼠PAF、ET-1、sICAM-1、PGE2水平较健康小鼠增加,在经过ACE2或CAP治疗后,上述炎性因子水平降低,提示ACE2或CAP具有抗炎作用,从而减轻炎症对VILI小鼠的肺损伤。Mungunsukh等[19]和Boskabadi等[20]的研究均表明CAP具有抑制肺损伤所引起的炎症反应的作用。Ye等[21]指出ACE2同样具有抗LPS诱导肺损伤引发的炎症效应。本研究与上述研究结果相似。

vWF是ALI肺内皮损伤的标志物[22],TM反映血管内皮损伤的严重程度[23]。PGI2能够减轻脂多糖诱导的ALI,并改善内皮屏障的恢复,降低炎症反应[24]。结果显示,VILI模型小鼠比健康小鼠血清和肺组织中TM、PGI2的水平降低,vWF水平增加;BALF中总蛋白和sICAM-1增加;在经过ACE2或者CAP干预后,血清中TM和PGI2的水平增加,vWF水平下降,BALF中总蛋白和sICAM-1降低,提示ACE2和CAP可以减少VILI的肺内皮细胞的损伤。研究已表明ACE2、CAP均具有改善内皮细胞的功能[25-26],本研究的结果与上述研究的结果相似。

ACE2和Ang(1-7)是心血管系统的关键保护因子,ACE2能够通过增进Ang(1-7)的生成,对ALI发挥保护功能[6]。Ang(1-9)可通过ACE或中性肽链内切酶的进一步水解作用,生成更多的Ang(1-7)[27]。ACE2水平降低会导致Ang(1-7)表达降低,从而致使Ang(1-7)与Mas受体结合后发挥的抗肺泡细胞凋亡、抗纤维化、抗炎等作用被削减[28-29],同时Ang Ⅱ的水平增加,促进炎症、纤维化等发展, 导致多器官病变、衰竭等[30]。本实验结果显示,VILI模型小鼠比健康小鼠血清和肺组织中Ang(1-7)、Ang(1-9)水平降低;在经过ACE2或者CAP干预后,血清和肺组织中Ang(1-7)、Ang(1-9)的水平增加。为了进一步证实ACE2和CAP对ACE2/Ang(1-9)/Ang(1-7)轴的调控,进一步检测各组肺组织中ACE2蛋白和mRNA的表达量。结果显示,经过ACE2或者CAP干预后,VILI模型小鼠肺组织中ACE2的蛋白和mRNA表达量均上升,提示ACE2和CAP可以通过调节ACE2/Ang(1-9)/Ang(1-7)轴发挥对VILI的保护作用。对于正常的小鼠,腹腔注射ACE2或CAP,所检测的指标均未发生显著变化,提示本实验所使用的ACE2或者CAP的剂量对正常小鼠没有显著的影响作用,且能对VILI发挥一定的保护作用。已有研究表明可以通过调节ACE2/Ang(1-7)/Mas轴降低炎症因子水平,改善肺损伤程度[31]。对于VILI模型小鼠,给予ACE2或者CAP,有助于抑制肺损伤,这与Li等[32]、Ye等[21]的研究结果一致,即CAP、ACE2一方面通过减轻炎症效应,另一方面通过增强ACE2的活力减轻肺损伤程度。

综上所述,腹腔注射ACE2或CAP均能降低VILI小鼠血清和肺组织中PAF、ET-1、sICAM-1、PGE2及vWF的水平,提高TM、Ang(1-9)、Ang(1-7)、PGI2的水平,ACE2蛋白和基因的表达水平显著增加,说明ACE2和CAP对VILI具有保护作用,ACE2和CAP均可以抑制炎症、保护心血管系统,ACE2和CAP可能是通过ACE2/Ang(1-9)/Ang(1-7)轴的作用,发挥对VILI的保护作用。VILI是一个复杂的过程,尚需要更多的研究证实ACE2、CAP对VILI的作用及相关机制。

利益冲突  所有作者声明无利益冲突

作者贡献声明  许俊平:论文撰写;陈霖、余天兴:研究设计、论文修改;张学平,谢万,张耿:实验操作、数据收集及整理;林新:提供研究经费、文章指导

参考文献
[1] Vieillard-Baron A, Matthay M, Teboul JL, et al. Experts' opinion on management of hemodynamics in ARDS patients: focus on the effects of mechanical ventilation[J]. Intensive Care Med, 2016, 42(5): 739-749. DOI:10.1007/s00134-016-4326-3
[2] Kittana N. Angiotensin-converting enzyme 2-angiotensin 1-7/1-9 system: novel promising targets for heart failure treatment[J]. Fundam Clin Pharmacol, 2018, 32(1): 14-25. DOI:10.1111/fcp.12318
[3] Bhushan S, Xiao ZW, Gao K, et al. Role and interaction between ACE1 ACE2 and their related genes in cardiovascular disorders[J]. Curr Probl Cardiol, 2023, 48(8): 101162. DOI:10.1016/j.cpcardiol.2022.101162
[4] Liu XH, Sun YT, Wei QL, et al. Captopril alleviates glucocorticoid-induced osteonecrosis of the femoral head by mediating the ACE2/Ang-(1-7)/Mas receptor cascade[J]. Eur J Pharmacol, 2022, 921: 174871. DOI:10.1016/j.ejphar.2022.174871
[5] Simões e Silva AC, Silveira KD, Ferreira AJ, et al. ACE2, angiotensin-(1-7) and Mas receptor axis in inflammation and fibrosis[J]. Br J Pharmacol, 2013, 169(3): 477-492. DOI:10.1111/bph.12159
[6] Liu L, Li Y, Li JX, et al. ACE2 expressed on myeloid cells alleviates sepsis-induced acute liver injury via the ang-(1-7)-mas receptor axis[J]. Inflammation, 2024, 47(3): 891-908. DOI:10.1007/s10753-023-01949-5
[7] Zhu XJ, Mou ZX, Han W, et al. All-trans retinoic acid inhibits oxidative stress via ACE2/Ang (1-7)/MasR pathway in renal tubular epithelial cells stimulated with high glucose[J]. Drug Dev Res, 2023, 84(5): 1008-1017. DOI:10.1002/ddr.22070
[8] 郭君平, 潘然, 王丽君, 等. 利拉鲁肽对脓毒症小鼠急性肺损伤的保护作用及其机制[J]. 中华急诊医学杂志, 2024, 33(8): 1134-1139. DOI:10.3760/cma.j.issn.1671-0282.2024.08.010
[9] Li WF, Zhao RQ, Wang XM, et al. Nobiletin-ameliorated lipopolysaccharide-induced inflammation in acute lung injury by suppression of NF-κB pathway in vivo and vitro[J]. Inflammation, 2018, 41(3): 996-1007. DOI:10.1007/s10753-018-0753-3
[10] McVey MJ, Kapur R, Cserti-Gazdewich C, et al. Transfusion-related acute lung injury in the perioperative patient[J]. Anesthesiology, 2019, 131(3): 693-715. DOI:10.1097/ALN.0000000000002687
[11] Hu M, Yang JL, Xu Y. Effect of α-tocopherol in alleviating the lipopolysaccharide-induced acute lung injury via inhibiting nuclear factor kappa-B signaling pathways[J]. Bioengineered, 2022, 13(2): 3958-3968. DOI:10.1080/21655979.2022.2031399
[12] Xia XY, Wen CX, Cao WH, et al. Customized screening of ACE2 regulatory peptides from oyster to mitigate LPS-induced acute lung injury based on SPR technology[J]. Food Biosci, 2025, 68: 106754. DOI:10.1016/j.fbio.2025.106754
[13] Boskabadi J, Askari VR, Hosseini M, et al. Immunomodulatory properties of captopril, an ACE inhibitor, on LPS-induced lung inflammation and fibrosis as well as oxidative stress[J]. Inflammopharmacology, 2019, 27(3): 639-647. DOI:10.1007/s10787-018-0535-4
[14] Groves AM, Paris ND, Johnston CJ, et al. Mitigating viral impact on the radiation response of the lung[J]. Radiat Res, 2024, 202(3): 552-564. DOI:10.1667/RADE-24-00103.1
[15] Jiang T, Samapati R, Klassen S, et al. Mannose-6-phosphate attenuates acute lung injury by competitive release of acid sphingomyelinase from the mannose-6-phosphate receptor in endothelial caveolae[J]. Eur Respir J, 2025, 65(6): 2400003. DOI:10.1183/13993003.00003-2024
[16] Kurt A, Kalkan Y, Turut H, et al. Topiramate reduces aortic cross-clamping-induced lung injury in male rats[J]. Acta Medica (Hradec Kralove), 2018, 61(4): 144-149. DOI:10.14712/18059694.2018.133
[17] Yilmaz Y, Tumkaya L. Effects of hyperbaric oxygen and iloprost on intestinal ischemia-reperfusion induced acute lung injury[J]. Ann Surg Treat Res, 2019, 96(1): 34-40. DOI:10.4174/astr.2019.96.1.34
[18] Hezam K, Wang C, Fu EZ, et al. Superior protective effects of PGE2 priming mesenchymal stem cells against LPS-induced acute lung injury (ALI) through macrophage immunomodulation[J]. Stem Cell Res Ther, 2023, 14(1): 48. DOI:10.1186/s13287-023-03277-9
[19] Mungunsukh O, George J, McCart EA, et al. Captopril reduces lung inflammation and accelerated senescence in response to thoracic radiation in mice[J]. J Radiat Res, 2021, 62(2): 236-248. DOI:10.1093/jrr/rraa142
[20] Boskabadi J, Mokhtari-Zaer A, Abareshi A, et al. The effect of captopril on lipopolysaccharide-induced lung inflammation[J]. Exp Lung Res, 2018, 44(4/5): 191-200. DOI:10.1080/01902148.2018.1473530
[21] Ye RS, Liu ZW. ACE2 exhibits protective effects against LPS-induced acute lung injury in mice by inhibiting the LPS-TLR4 pathway[J]. Exp Mol Pathol, 2020, 113: 104350. DOI:10.1016/j.yexmp.2019.104350
[22] El Basset Abo El Ezz AA, Abd El Hafez MA, El Amrousy DM, et al. The predictive value of Von Willebrand factor antigen plasma levels in children with acute lung injury[J]. Pediatr Pulmonol, 2017, 52(1): 91-97. DOI:10.1002/ppul.23518
[23] Watanabe-Kusunoki K, Nakazawa D, Ishizu A, et al. Thrombomodulin as a physiological modulator of intravascular injury[J]. Front Immunol, 2020, 11: 575890. DOI:10.3389/fimmu.2020.575890
[24] Toki S, Zhou WS, Goleniewska K, et al. Endogenous PGI2 signaling through IP inhibits neutrophilic lung inflammation in LPS-induced acute lung injury mice model[J]. Prostaglandins Other Lipid Mediat, 2018, 136: 33-43. DOI:10.1016/j.prostaglandins.2018.04.001
[25] He YX, Gang BC, Zhang MJ, et al. ACE2 improves endothelial cell function and reduces acute lung injury by downregulating FAK expression[J]. Int Immunopharmacol, 2024, 128: 111535. DOI:10.1016/j.intimp.2024.111535
[26] Wei JN, Xu H, Liu YY, et al. Effect of captopril on radiation-induced TGF-β1 secretion in EA.Hy926 human umbilical vein endothelial cells[J]. Oncotarget, 2017, 8(13): 20842-20850. DOI:10.18632/oncotarget.15356
[27] 郑梦迪, 王治. ACE2-Ang(1-7)-MasR轴对心血管系统保护作用的研究进展[J]. 中国心血管病研究, 2024, 22(6): 517-521. DOI:10.3969/j.issn.1672-5301.2024.06.003
[28] Pan H, Huang WH, Wang ZJ, et al. The ACE2-ang-(1-7)-mas axis modulates M1/M2 macrophage polarization to relieve CLP-induced inflammation via TLR4-mediated NF-кb and MAPK pathways[J]. J Inflamm Res, 2021, 14: 2045-2060. DOI:10.2147/JIR.S307801
[29] Abdel-Fattah MM, Elgendy ANAM, Mohamed WR. Xanthenone, ACE2 activator, counteracted gentamicin-induced nephrotoxicity in rats: Impact on oxidative stress and ACE2/Ang-(1-7) signaling[J]. Life Sci, 2021, 275: 119387. DOI:10.1016/j.lfs.2021.119387
[30] Wang CL, Ren LY, Chen SK, et al. Longdan Xiegan Tang attenuates liver injury and hepatic insulin resistance by regulating the angiotensin-converting enzyme 2/Ang (1-7)/Mas axis-mediated anti-inflammatory pathway in rats[J]. J Ethnopharmacol, 2021, 274: 114072. DOI:10.1016/j.jep.2021.114072
[31] Scozzi D, Liao FY, Krupnick AS, et al. The role of neutrophil extracellular traps in acute lung injury[J]. Front Immunol, 2022, 13: 953195. DOI:10.3389/fimmu.2022.953195
[32] Li YC, Zeng Z, Li YC, et al. Angiotensin-converting enzyme inhibition attenuates lipopolysaccharide-induced lung injury by regulating the balance between angiotensin-converting enzyme and angiotensin-converting enzyme 2 and inhibiting mitogen-activated protein kinase activation[J]. Shock, 2015, 43(4): 395-404. DOI:10.1097/SHK.0000000000000302