CAJ | 학술논문

目的探讨自噬对急性脓毒症大鼠心功能的影响以及线粒体辅酶Q(MitoQ)是否通过自噬对急性脓毒症大鼠心功能障碍起保护作用.方法 SD雄性大鼠45只,按随机数字表法随机分9组:对照组,脂多糖(LPS)4 h、6h、12h组,LPS+渥曼青霉素(Wortmannin)4 h组,LPS+ MitoQ 4 h、6h组,MitoQ组,Wortmannin组,每组5只,每只大鼠予LPS(10 mg/kg)腹腔注射,LPS注射后1h采用尾静脉注射分别给Wortmannin(2 mgkg)、MitoQ(6.5 μmol/kg),LPS组给等量9 g/L盐水注射.BL-420E+生物信号采集系统测定左心室最大收缩压(LVSP)、左心室舒张末压(LVEDP)、左心室压力上升/下降最大速率(±dp/dt max)数据.留取血标本测血清肌酸激酶同工酶(CK-MB)水平.取出心肌组织ELISA法测活性氧(ROS)水平,Western blot法检测微管相关蛋白轻链3(LC3)蛋白的表达,光镜和电镜观察心肌病理改变.结果 LPS注射后6 h LVSP、LVEDP、±dp/dtmax与对照组比较差异均有统计学意义(P＜0.05);给LPS后再给Wortmannin 4 h即出现统计学差异(P＜0.05);LPS+ MitoQ 6 h组与对照组比较差异有统计学意义(P＜0.05),但与同时间点LPS组比较差异无统计学意义(P＞0.05).血清CK-MB及心肌组织ROS水平LPS6h组、LPS+ MitoQ 6 h组和LPS+ Wortmannin 4 h组均高于对照组(P＜0.05).光镜下对照组心肌细胞排列规则,心肌间质无炎性细胞浸润;LPS6 h组、LPS+MitoQ 6 h组和LPS+ Wortmannin 4 h组心肌纤维结构紊乱,间质大量炎性细胞浸润.电镜下,给LPS6h后自噬体增多,随着时间延长到12 h自噬体无明显增多,给MitoQ后与相应时间点LPS组比较自噬体数量无差异.Western blot检测发现LPS6 h组和LPS+ MitoQ 6 h组LC3-Ⅱ蛋白水平均高于对照组(P＜0.05),但LPS 12 h组和6h组比较差异无统计学意义(P＞0.05).结论线粒体靶向抗氧化剂MitoQ对脓毒症大鼠心功能障碍无保护作用.自噬对脓毒症大鼠心功能障碍起保护作用,且自噬能力或自噬体形成速率决定是否出现心功能障碍. 目的探討自噬對急性膿毒癥大鼠心功能的影響以及線粒體輔酶Q(MitoQ)是否通過自噬對急性膿毒癥大鼠心功能障礙起保護作用.方法 SD雄性大鼠45隻,按隨機數字錶法隨機分9組:對照組,脂多糖(LPS)4 h、6h、12h組,LPS+渥曼青黴素(Wortmannin)4 h組,LPS+ MitoQ 4 h、6h組,MitoQ組,Wortmannin組,每組5隻,每隻大鼠予LPS(10 mg/kg)腹腔註射,LPS註射後1h採用尾靜脈註射分彆給Wortmannin(2 mgkg)、MitoQ(6.5 μmol/kg),LPS組給等量9 g/L鹽水註射.BL-420E+生物信號採集繫統測定左心室最大收縮壓(LVSP)、左心室舒張末壓(LVEDP)、左心室壓力上升/下降最大速率(±dp/dt max)數據.留取血標本測血清肌痠激酶同工酶(CK-MB)水平.取齣心肌組織ELISA法測活性氧(ROS)水平,Western blot法檢測微管相關蛋白輕鏈3(LC3)蛋白的錶達,光鏡和電鏡觀察心肌病理改變.結果 LPS註射後6 h LVSP、LVEDP、±dp/dtmax與對照組比較差異均有統計學意義(P＜0.05);給LPS後再給Wortmannin 4 h即齣現統計學差異(P＜0.05);LPS+ MitoQ 6 h組與對照組比較差異有統計學意義(P＜0.05),但與同時間點LPS組比較差異無統計學意義(P＞0.05).血清CK-MB及心肌組織ROS水平LPS6h組、LPS+ MitoQ 6 h組和LPS+ Wortmannin 4 h組均高于對照組(P＜0.05).光鏡下對照組心肌細胞排列規則,心肌間質無炎性細胞浸潤;LPS6 h組、LPS+MitoQ 6 h組和LPS+ Wortmannin 4 h組心肌纖維結構紊亂,間質大量炎性細胞浸潤.電鏡下,給LPS6h後自噬體增多,隨著時間延長到12 h自噬體無明顯增多,給MitoQ後與相應時間點LPS組比較自噬體數量無差異.Western blot檢測髮現LPS6 h組和LPS+ MitoQ 6 h組LC3-Ⅱ蛋白水平均高于對照組(P＜0.05),但LPS 12 h組和6h組比較差異無統計學意義(P＞0.05).結論線粒體靶嚮抗氧化劑MitoQ對膿毒癥大鼠心功能障礙無保護作用.自噬對膿毒癥大鼠心功能障礙起保護作用,且自噬能力或自噬體形成速率決定是否齣現心功能障礙.
목적 탐토자서대급성농독증대서심공능적영향이급선립체보매Q(MitoQ)시부통과자서대급성농독증대서심공능장애기보호작용.방법 SD웅성대서45지,안수궤수자표법수궤분9조:대조조,지다당(LPS)4 h、6h、12h조,LPS+악만청매소(Wortmannin)4 h조,LPS+ MitoQ 4 h、6h조,MitoQ조,Wortmannin조,매조5지,매지대서여LPS(10 mg/kg)복강주사,LPS주사후1h채용미정맥주사분별급Wortmannin(2 mgkg)、MitoQ(6.5 μmol/kg),LPS조급등량9 g/L염수주사.BL-420E+생물신호채집계통측정좌심실최대수축압(LVSP)、좌심실서장말압(LVEDP)、좌심실압력상승/하강최대속솔(±dp/dt max)수거.류취혈표본측혈청기산격매동공매(CK-MB)수평.취출심기조직ELISA법측활성양(ROS)수평,Western blot법검측미관상관단백경련3(LC3)단백적표체,광경화전경관찰심기병리개변.결과 LPS주사후6 h LVSP、LVEDP、±dp/dtmax여대조조비교차이균유통계학의의(P＜0.05);급LPS후재급Wortmannin 4 h즉출현통계학차이(P＜0.05);LPS+ MitoQ 6 h조여대조조비교차이유통계학의의(P＜0.05),단여동시간점LPS조비교차이무통계학의의(P＞0.05).혈청CK-MB급심기조직ROS수평LPS6h조、LPS+ MitoQ 6 h조화LPS+ Wortmannin 4 h조균고우대조조(P＜0.05).광경하대조조심기세포배렬규칙,심기간질무염성세포침윤;LPS6 h조、LPS+MitoQ 6 h조화LPS+ Wortmannin 4 h조심기섬유결구문란,간질대량염성세포침윤.전경하,급LPS6h후자서체증다,수착시간연장도12 h자서체무명현증다,급MitoQ후여상응시간점LPS조비교자서체수량무차이.Western blot검측발현LPS6 h조화LPS+ MitoQ 6 h조LC3-Ⅱ단백수평균고우대조조(P＜0.05),단LPS 12 h조화6h조비교차이무통계학의의(P＞0.05).결론 선립체파향항양화제MitoQ대농독증대서심공능장애무보호작용.자서대농독증대서심공능장애기보호작용,차자서능력혹자서체형성속솔결정시부출현심공능장애.
Objective To investigate the effects of autophagy on cardiac function and to determine whether the mitochondrial coenzyme Q (MitoQ) prevents cardiac dysfunction,mediated by autophagy,in rats with acute sepsis.Methods Forty-five Sprague Dawley (SD) rats were randomly divided into 9 groups (n =5,each group):control group,4 h lipopolysaccharide(LPS) group,6 h LPS group,12 h LPS group,4 h LPS + Wortmannin group,4 h LPS + MitoQ group,6 h LPS + MitoQ group,MitoQ group and Wortmannin group.Rats in LPS + Wortmannin group and LPS + MitoQ group were intraperitoneally given LPS(10 mg/kg) and followed by an injection of Wortmannin(2 mg/kg) and MitoQ (6.5 μmol/kg) via tail vein 1 hour later,respectively.Rats in each group were given the same amount of normal sodium in addition to different intervention drugs.The cardiac function parameters were measured by a BL-420E + biosignal collection system.Blood samples from abdominal aorta were taken at each time point,and creatine kinase MB isoenzyme (CK-MB) content was detected by using the velocity method.The content of reactive oxygen species (ROS) in isolated myocardial tissues in rats was measured by enzyme-linked immunoadsorbent assay(ELISA).The protein expression of microtubule-associated protein 1 light chain 3 (LC3) was detected by Western blot method.The pathological changes of myocardial tissue were observed by light and electronic microscopy.Results Compared with the control group,the left ventricular systolic pressure(LVSP),the rate of the rise in left ventricular pressure (± dp/dt max) were significantly decreased in 6 h LPS group,6 h LPS + MitoQ group and 4 h LPS + Wortmannin group(P ＜0.05),left ventricular end-diastolic pressure(LVEDP) was significantly increased in these 3 groups(P ＜0.05).The contents of CKMB and ROS in 6 h LPS group,6 h LPS =MitoQ group and 4 h LPS + Wortmannin group were higher than those in the control group(P ＜ 0.05).Electron microscopy showed that the number of autophagic vacuoles increased 6 h after LPS was administered,but did not increase significantly thereafter to 12 h.There was no difference at any time point in the number of autophagic vacuoles in the group given MitoQ and LPS.Immunoblotting demonstrated that the levels of LC3Ⅱ protein in the LPS 6 h group and LPS + MitoQ 6 h group were higher than those in the control group(P ＜0.05),but there was no difference between the LPS 12 h and LPS 6 h groups (P ＞ 0.05).Conclusions The mitochondria-targeted antioxidant MitoQ does not prevent cardiac dysfunction.However,autophagy prevents cardiac dysfunction,and the autophagic capacity or autophagosome-formation rate may determine whether cardiac dysfunction develops.