摘要
目的:探究慢性应激对动脉粥样硬化(atherosclerosis,AS)小鼠心肌损伤的影响并揭示其潜在机制。方法:选用SPF级8周龄雄性C57BL/6J小鼠和ApoE^(−/−)小鼠。10周饮食干预后进行AS病理观察,AS鉴定成模后再复合慢性不可预计温和刺激(chronic unpredictable mild stress,CUMS)6周,分为五组:对照(control)组、CUMS组、AS-普通饲料喂养(AS-regular diet,AS-r)+CUMS组、AS-高脂饲料喂养(AS-high-fat diet,AS-h)组和AS-h+CUMS组,每组各10只。CUMS期间对各组小鼠进行旷场实验、糖水偏好实验;采用全自动生化分析仪检测小鼠血脂;HE、油红O染色评估主动脉根部病理改变;超声心动图评估小鼠心功能;ELISA法检测小鼠血清心肌损伤标志物含量、心肌组织ATP含量;透射电镜观察心肌线粒体超微结构;Oxygraph-2k高分辨呼吸能量代谢仪检测心肌线粒体耗氧率;Western blot检测B细胞淋巴瘤蛋白2(B-cell lymphoma-2,Bcl-2)、Bcl-2相关X蛋白(Bcl-2-associated X protein,Bax)和cleaved caspase-3蛋白表达。结果:与control组相比各CUMS组运动总路程、进入中央区次数、糖水偏好率均显著下降(P<0.05);各AS组主动脉根部均出现了不同程度的脂质沉积及内皮损伤,心功能均显著下降(P<0.05)、并伴随不同程度心肌损伤(P<0.05);AS-h+CUMS、AS-r+CUMS心肌线粒体结构破坏,ATP含量显著下降(P<0.05),线粒体呼吸链复合物I支持的呼吸、线粒体呼吸链复合物Ⅰ+Ⅱ支持的呼吸和电子传递系统最大呼吸能力均显著下降(P<0.05);Bax和cleaved caspase-3蛋白表达显著升高(P<0.05),Bcl-2蛋白表达显著降低(P<0.05)。结论:慢性应激通过破坏AS小鼠心肌线粒体结构及能量代谢功能导致线粒体非稳态负荷发生,进而加剧心肌细胞凋亡加重心肌损伤。
AIM:To investigate the mechanism of chronic stress-induced myocardial injury in atherosclerotic(AS)mice.METHODS:Eight-week-old SPF-grade male ApoE^(−/−)mice and C57BL/6J mice used in this study.The mice received dietary intervention for 10 weeks followed by pathological examination to test the successful AS modeling.After AS establishment,the mice were exposed to chronic unpredictable mild stress(CUMS)for 6 weeks and then divided into five groups:control,CUMS,AS-regular diet(AS-r)+CUMS,AS-high-fat diet(AS-h),and AS-h+CUMS.During CUMS,open-field test and sucrose preference test were performed on mice in all groups.Blood lipids were characterized using an automatic biochemical analyzer.Hematoxylin-eosin(HE)and oil red O staining were performed to evaluate pathological changes in the aortic root.Cardiac function was assessed using echocardiography.The serum concentration of myocardial injury markers and ATP content was detected by ELISA.Transmission electron microscopy was employed to observe the ultrastructure of myocardial mitochondria.Myocardial mitochondrial oxygen consumption rate was determined using the Oxygraph-2k high-resolution respiratory energy metabolism analyzer.Western blot was conducted to quantify the expression of B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),and cleaved caspase-3.RESULTS:compared with the Control group,the total distance traveled,the number of entries into the central area,and the sucrose preference rate were significantly decreased in all CUMS groups(P<0.05).All AS groups exhibited varying levels of lipid deposition and endothelial damage in the aortic root,along with a significant reduction in cardiac function(P<0.05)and varying degrees of myocardial injury(P<0.05).In the AS-h+CUMS and AS-r+CUMS groups,myocardial mitochondrial structure was significantly disrupted.ATP content was significantly reduced(P<0.05),and the rates of oxygen consumption associated with mitochondrial respiratory chain complex I,mitochondrial respiratory chain complexes Ⅰ+Ⅱ,and the maxim
作者
倪萍
刘思彤
孙瑞鸽
马海钧
孙红
张欢
梁健
杜成渝
于游
于睿
NI Ping;LIU Sitong;SUN Ruige;MA Haijun;SUN Hong;ZHANG Huan;LIANGJian;DU Chengyu;YU You;YU Rui(Liaoning University of Traditional Chinese Medicine,Shenyang 110847,China;The Second Affiliated Hospital of Liaoning University of Traditional Chinese Medicine,Shenyang 110031,China)
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2024年第9期1635-1644,共10页
Chinese Journal of Pathophysiology
基金
国家自然科学基金面上项目(No.82274494)
辽宁省博士科研启动基金计划项目(No.2023-BS-049)
辽宁省科学技术计划项目(No.2023JH2/101600030)
辽宁省中医药研究院科研项目(No.2022LZYY04)。
关键词
动脉粥样硬化
慢性应激
心肌损伤
线粒体
线粒体非稳态负荷
atherosclerotic
chronic stress
myocardial injury
mitochondria
mitochondrial allostatic load
