抑制乙酰辅酶A羧化酶2改善脓毒症小鼠心功能障碍的机制研究  

Mechanism of inhibiting acetyl CoA carboxylase 2 to improve cardiac dysfunction in septic mice

作　　者：杜云霞 佘汉 吴银雨 王易 周远群 王维飞 李涛 胡弋 毛庆祥 DU Yunxia;SHE Han;WU Yinyu;WANG Yi;ZHOU Yuanqun;WANG Weifei;LI Tao;HU Yi;MAO Qingxiang(Department of Anesthesiology,Institute of Field Surgery,Army Medical Center of PLA,Chongqing,400042,China;Department of Shock and Transfusion,Institute of Field Surgery,Army Medical Center of PLA,Chongqing,400042,China)

机构地区：[1]陆军特色医学中心:麻醉科,重庆400042 [2]陆军特色医学中心:野战外科研究部战伤休克与输血研究室,重庆400042

出　　处：《陆军军医大学学报》2024年第24期2689-2697,共9页Journal of Army Medical University

基　　金：国家自然科学基金青年科学基金项目(82300561);重庆英才创新领军人才项目(CSTC2024YCJH-BGZXM0011);重庆市自然科学基金面上项目(CSTB2023NSCQ-MSX0713)。

摘　　要：目的观察抑制乙酰辅酶A羧化酶2(acetyl-CoA carboxylase 2,ACC2)对脓毒症小鼠心脏功能障碍的改善作用并研究其机制。方法采用盲肠结扎穿孔术建立小鼠脓毒症模型,取24只8周龄且体质量为20~25 g的雄性C57BL/6小鼠,按照随机数字表法分为假手术组、脓毒症组、ND-630+脓毒症组。利用Cre-LoxP重组酶系统构建心脏特异性ACC2敲除小鼠(ACC2ΔCM),并以ACC2 flox/flox Myh6-Cre-(ACC2 fl/fl)小鼠作为对照,取48只ACC2 fl/fl小鼠、48只ACC2ΔCM小鼠(8周龄,20~25 g,雄性)按照随机数字表法分为ACC2 fl/fl+假手术组、ACC2 fl/fl+脓毒症组、ACC2ΔCM+脓毒症组、ACC2ΔCM+Mal-CoA+脓毒症组、ACC2ΔCM+假手术组。采用细胞微张力仪检测心肌细胞收缩功能与肌丝钙敏感性;Western blot检测ACC2蛋白表达水平;ELISA检测心肌组织中丙二酰辅酶A(malonyl-CoA,Mal-CoA)水平。观察小鼠脓毒症后36 h存活情况。结果脓毒症组较假手术组心肌细胞收缩幅度显著下降,钙敏感性显著下降(P<0.05);以ACC2 fl/fl+假手术组为基础水平,ACC2ΔCM+脓毒症组较ACC2 fl/fl+脓毒症组心肌细胞收缩幅度恢复48.1%,钙敏感性明显恢复(P<0.05);ACC2ΔCM+Mal-CoA+脓毒症组较ACC2ΔCM+脓毒症组心肌细胞收缩幅度与钙敏感性明显下降(P<0.05);ND-630+脓毒症组较脓毒症组心肌细胞收缩幅度与肌丝钙敏感性上升(P<0.05)。脓毒症组较假手术组小鼠心肌组织ACC2蛋白表达水平增加(P<0.05)。脓毒症组心肌Mal-CoA水平较假手术组升高(P<0.05);ACC2ΔCM+脓毒症组小鼠心肌Mal-CoA水平较脓毒症组降低(P<0.05)。ACC2ΔCM+脓毒症组较ACC2 fl/fl+脓毒症组36 h存活率提高37.5%(P<0.05)。结论抑制ACC2通过降低Mal-CoA水平对脓毒症小鼠心肌收缩功能和钙敏感性发挥保护作用。Objective To observe the ameliorative effect of inhibiting acetyl-CoA carboxylase 2(ACC2)on cardiac dysfunction in septic mice and investigate its underlying mechanism.Methods Mouse model of sepsis was established by cecal ligation and perforation.A total of 24 male C57BL/6 mice(aged 8 weeks,weighing 20~25 g)were divided into sham operation group,sepsis group and ND-630+sepsis group.The cardiac specific ACC2 knockout(ACC2ΔCM)mice were constructed by Cre-LoxP recombinase system,and ACC2 flox/flox Myh6-Cre-(ACC2 fl/fl)mice were used as control.Several genetically engineered mice(8 weeks old,20~25 g,male)were divided into ACC2 fl/fl+sham operation group,ACC2 fl/fl+sepsis group,ACC2ΔCM+sepsis group,ACC2ΔCM+Mal-CoA+sepsis group,and ACC2ΔCM+sham operation group according to the random number table method.The contractile function and myofilament calcium sensitivity of cardiomyocytes were measured by a cell microtensiometer.Western blotting was used to detect the expression level of ACC2,and ELISA was employed to measure the level of malonyl-CoA(Mal-CoA)in myocardial tissue.The survival of the mice in 36 h after sepsis was observed.Results Compared with the sham operation group,the contraction amplitude of cardiomyocytes in sepsis group was decreased markedly,and the calcium sensitivity decreased significantly as well(P<0.05).Based on the ACC2 fl/fl+sham operation group,the ACC2ΔCM+sepsis group showed significant improvement in myocardial contraction compared with the ACC2 fl/fl+sepsis group,with the contraction amplitude of cardiomyocytes recovered by 48.1%,and significantly restored calcium sensitivity(P<0.05).ACC2ΔCM+Mal-CoA+sepsis group showed a notable decrease in myocardial cell contraction amplitude and a significant decrease in calcium sensitivity when compared to the ACC2ΔCM+sepsis group(P<0.05).Compared with the sepsis group,the contraction amplitude of cardiomyocytes in the ND-630+sepsis group increased significantly,and the calcium sensitivity of myofilament also increased(P<0.05).The expression level

关 键 词：脓毒症 心肌细胞 乙酰辅酶A羧化酶2 钙敏感性 丙二酰辅酶A 

分 类 号：R322.11[医药卫生—人体解剖和组织胚胎学] R631.1[医药卫生—基础医学] R977.3