摘要
目的全反式维甲酸(all-trans retinoic acid,ATRA)对异丙肾上腺素(isoprenaline,ISO)诱导下大鼠心肌纤维化和心肌重构的影响及作用机制。方法将大鼠按随机数表法分为4组:对照组、ISO组、ATRA+ISO组、4-PBA(4-苯基丁酸,4-phenylbutyric acid)+ISO组,每组10只;ATRA+ISO组和4-PBA+ISO组预先分别通过腹腔注射ATRA与4-PBA,然后再通过背部皮下注射ISO进行诱导。心脏超声检测各组大鼠左心室舒张末期内径(left ventricular internal diameter in diastole,LVIDd)、左心室收缩末期内径(left ventricular internal diameter in systole,LVIDs)、左心室的射血分数(ejection fraction,EF)及短轴缩短率(fractional shortening,FS),称量各组大鼠体重、全心质量及左心室质量,计算全心质量指数(heart mass index,HMI)与左心室质量指数(left ventricle mass index,LVMI)。ELISA测定各组大鼠血清N端B型利钠肽原(N terminal pro B type natriuretic peptide,NT-proBNP)含量。HE染色和Masson染色观察各组大鼠心肌组织病理学变化与胶原纤维化程度。蛋白质印迹检测心肌组织中G蛋白偶联受体78(glucose-regulated protein 78,GRP78)、C/EBP同源蛋白(C/EBP homology protein,CHOP)、蛋白激酶R样内质网激酶(protein kinase R-like ER kinase,PERK)、磷酸化真核翻译起始因子2α(phosphorylated eukaryotic translation initiation factor 2α,p-eIF2α)、转化生长因子-β1(transforming growth factor-β1,TGF-β1)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、胶原蛋白Collagen-Ⅰ及Collagen-Ⅲ的蛋白表达。结果与对照组比较,ISO组大鼠EF和FS显著降低(P<0.05),LVIDd、LVIDs、HMI及LVMI显著升高(P<0.05),血清NTproBNP含量显著增加(P<0.05),心肌组织病理损伤明显,胶原纤维面积显著增加(P<0.05),心肌组织中GRP78、CHOP、PERK、p-eIF2α、TGF-β1、α-SMA、Collagen-Ⅰ及Collagen-Ⅲ蛋白表达均显著上调(P<0.05);与ISO组比较,ATRA+ISO组和4-PBA+ISO组的大鼠EF和FS显著升高(P<0.05),LVIDd、LVIDs、HMI及LVMI显著降低(P<0.05),血清NT-proBNP含量显著减少(P<0.05),心肌组织损伤程度明显减轻,胶原纤维面积显著减小(P<0.05),心肌组织中GRP78、CHOP、PERK、p-eIF2α、TGF-β1、α-SMA、Collagen-Ⅰ及Collagen-Ⅲ蛋白表达均显著下调(P<0.05)。结论ATRA能够减轻ISO诱导的大鼠心肌损伤及其纤维化,抑制心肌重构,改善心功能,该作用与其抑制内质网应激反应有关。
Objective To investigate the effects of all-trans retinoic acid(ATRA)on myocardial fibrosis and myocardial remodeling induced by isoproterenol(ISO)in rats,and to analyze its mechanism.Methods The rats were randomly divided into 4 groups:control group,ISO group,ATRA+ISO group,4-phenylbutyric acid(4-PBA)+ISO group,with 10 rats in each group.Rats in the ATRA+ISO group and the 4-PBA+ISO group were administrated with ATRA and 4-PBA through intraperitoneal injection respectively.Rats in the ISO group,the ATRA+ISO group and the 4-PBA+ISO group were administrated with ISO through subcutaneous injection on the back.The left ventricular internal diameter in diastole(LVIDd),left ventricular internal diameter in systole(LVIDs),left ventricular ejection fraction(EF)and fractional shortening(FS)were detected by cardiac ultrasound.The body weight,whole heart mass and left ventricular mass of rats were weighed,and the whole heart mass index(HMI)and left ventricular mass index(LVMI)were calculated.The level of serum N-terminal pro B type natriuretic peptide(NT-proBNP)was determined by ELISA.HE staining and Masson staining were used to observe the histopathological changes and the degree of collagen fibrosis in rat myocardial tissues,respectively.The protein expression levels of G protein-coupled receptor 78(GRP78),C/EBP homologous protein(CHOP),protein kinase R-like endoplasmic reticulum kinase(PERK),phosphorylated eukaryotic translation initiation factor 2α(p-eIF2α),and transforming growth factor-β1(TGF-β1),α-smooth muscle actin(α-SMA),Collagen-I and Collagen-Ⅲin myocardial tissues were determined by Western blotting.Results When compared with those in the control group,the EF and FS in the ISO group were significantly decreased(P<0.05),the LVIDd,LVIDs,HMI and LVMI were significantly increased(P<0.05),the level of serum NT-proBNP was significantly increased(P<0.05),the pathological injury of myocardial tissues was observed,the areas with collagen fiber had significantly increased(P<0.05),the protein expression levels of GRP78,CHOP,PERK,P-EIF2α,TGF-β1,α-SMA,CollagenⅠand CollagenⅢin the myocardial tissues were significantly up-regulated(P<0.05).When compared with those in the ISO group,the EF and FS in the ATRA+ISO group and the 4-PBA+ISO group were significantly increased(P<0.05),the LVIDd,LVIDs,HMI and LVMI were significantly decreased(P<0.05),and the level of serum NT-proBNP was significantly decreased(P<0.05),the degree of myocardial injury was significantly reduced,the area with collagen fiber had significantly reduced(P<0.05),and the protein expression levels of GRP78,CHOP,PERK,P-EIF2α,TGF-β1,α-SMA,CollagenⅠand CollagenⅢin the myocardial tissue were significantly down-regulated(P<0.05).Conclusion ATRA can alleviate ISOinduced myocardial injury and fibrosis,inhibit myocardial remodeling and improve cardiac function through the inhibition of endoplasmic reticulum stress response.
作者
魏俊萍
孟庆雯
林道飞
林燕仔
符达佳
WEI Junping;MENG Qingwen;LIN Daofei;LIN Yanzai;FU Dajia(Department of Cardiology,First Affiliated Hospital of Hainan Medical College,Haik-ou,570102,China;ECG Room,First Affiliated Hospital of Hainan Medical College,Haik-ou,570102,China)
出处
《医学分子生物学杂志》
CAS
2024年第3期203-210,共8页
Journal of Medical Molecular Biology
基金
海南省卫生健康行业科研项目(No.22A200077)
海南省自然科学基金青年项目(No.821QN401)
海南医学院第一附属医院青年培育基金(No.HYYFYPY202020)。
关键词
心肌重构
心肌纤维化
异丙肾上腺素
全反式维甲酸
内质网应激
myocardial remodeling
myocardial fibrosis
isoproterenol
all-trans retinoic acid
endoplasmic reticulum stress
