摘要
目的:观察槲皮素(Que)是否具有通过上调沉默信息调控因子1(SIRT1)的表达发挥降低心肌缺血/再灌注(I/R)后微血管通透性的作用,并初步探讨其机制。方法:SD大鼠(220~250 g)随机分为假手术(sham)组(只穿线不结扎)、I/R组(缺血30 min/再灌注60 min)、I/R+Que组(再灌注前15 min静脉注射10 mg/kg Que)和I/R+Que+EX527(SIRT1的抑制剂)组(静脉注射Que前15 min静脉注射1 mg/kg EX527)。HE染色法观察Que对I/R心肌微血管形态的影响。ELISA检测各组大鼠外周血清中内皮损伤标志物和炎症因子的表达。Transwell小室中培养H5V细胞,观察Que对单层内皮细胞通透性的影响,Western blot及免疫荧光检测SIRT1、肌球蛋白轻链磷酸酶(MLCP)和紧密连接蛋白ZO-1的表达以及细胞骨架的排列情况。结果:心肌组织发生I/R时,SIRT1的表达明显降低,外源性Que干预后,SIRT1的表达上调,Que的上调作用可被EX527阻断。I/R+Que组与I/R组相比,心率失常的发生率明显降低,微血管完整性更好,炎症细胞浸润显著减少,内皮损伤标志物E-选择素和VCAM-1明显减少,促炎因子PAF、IL-1α和IL-6的表达也明显降低,但以EX527抑制SIRT1的表达后,Que的上述作用明显减弱。细胞实验结果显示,缺氧/复氧可引起内皮细胞的通透性增加,ZO-1和MLCP的表达减少,细胞骨架重构,细胞收缩,Que上调SIRT1后,内皮细胞的通透性显著降低,ZO-1和MLCP的表达升高,细胞骨架排列基本恢复,以EX527抑制SIRT1表达后,Que的上述作用大幅度减弱。结论:Que具有降低心肌I/R时微血管通透性的作用,作用机制可能与SIRT1的上调有关。
AIM:To investigate whether quercetin(Que)attenuates microvascular injury after myocardial ischemia/reperfusion(I/R),and whether its mechanism is related to the up-regulation of silent information regulator 1(SIRT1).METHODS:In vivo,SD rats(220~250 g)were randomly divided into sham group(only threading without ligation),I/R group(ischemia 30 min/reperfusion 60 min),I/R+Que group(10 mg/kg Que injected intravenously 15 min before reperfusion)and I/R+Que+EX527 group(1 mg/kg EX527 injected intravenously 15 min before Que).The protein expression of SIRT1 in each group was determined by Western blot.The effect of Que on the morphological changes of myocardial microvascular was estimated by HE staining.The contents of endothelial damage markers and inflammatory factors in peripheral blood serum of the rats in each group were measured by ELISA.In vitro,Transwell chamber was used to culture H5 V cells and then the influence of Que on the permeability of endothelial cells was evaluated.The expression of myosin light chain phosphatase(MLCP),zonula occludens-1(ZO-1)and cytoskeleton was determined by Western blot and immunofluorescence method.RESULTS:The results of Western blot showed that SIRT1 was significantly reduced by I/R in the myocardial tissue.Que increased the expression of SIRT1 after I/R,whereas EX527 significantly inhibited this effect(P<0.05).Que reduced the incidence of I/R arrhythmia,alleviated microvascular damage and inhibited the infiltrating of inflammatory cells,as well as decreased levels of the endothelial injury markers(E-selectin and VCAM-1)and proinflammatory factors(PAF,IL-1αand IL-6).While EX527 significantly reduced these effects of Que by inhibiting SIRT1.Cultured H5 V cells showed that hypoxia/reoxygenation resulted in increased permeability of endothelial cells and decreased expression of ZO-1 and MLCP.However,Que,which up-regulated expression of SIRT1,significantly reduced the permeability of endothelial cells significantly and increased the expression of ZO-1 and MLCP.Meanwhile,the cytoskeleto
作者
刘振华
张艳红
董杰
韩丽萍
LIU Zhen-hua;ZHANG Yan-hong;DONG Jie;HAN Li-ping(Hypoxia Medical Institute,Wenzhou Medical University,Wenzhou 325035,China)
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2020年第4期644-651,共8页
Chinese Journal of Pathophysiology
基金
浙江省自然科学基金资助项目(No.LY17H020010)。
关键词
槲皮素
缺血/再灌注
微血管通透性
沉默信息调控因子1
心肌梗死
Quercetin
Ischemia/reperfusion
Microvascular permeability
Silent information regulator 1
Myocardial infarction
