虎杖苷调节Hippo/YAP信号通路对冠心病大鼠心肌损伤的影响

Effect of polydatin on myocardial injury in rats with coronary heart disease by regulating the Hippo/YAP signaling pathway

目的探讨虎杖苷(PD)对冠心病(CHD)大鼠心肌损伤及Hippo-Yes相关蛋白(YAP)信号通路的影响。方法构建CHD大鼠模型,将造模成功大鼠随机分为模型组(CHD组)、虎杖苷低、高剂量组(PD-L、PD-H组)、虎杖苷高剂量+Hippo/YAP信号通路激活剂PY-60组(PD-H+PY-60组),每组18只,另取18只正常大鼠作为对照组(Control组),超声心动图检测大鼠心功能。每组随机选择6只大鼠处死取心脏组织,HE染色观察大鼠心肌组织的病理形态变化,Masson染色观察大鼠心肌纤维化程度及胶原纤维化面积;TUNEL染色观察心肌组织中细胞凋亡情况;Western blot法检测B淋巴细胞瘤-2相关X蛋白(Bax)、半胱氨酸蛋白酶-3(Caspase-3)、p-YAP/YAP、具有PDZ结合模体的转录激活因子(TAZ)表达。结果CHD组较Control组心肌细胞异常,心肌纤维结构紊乱,炎性细胞浸润及组织水肿明显,蓝色胶原纤维沉积增多,心肌胶原纤维化面积占比增多,细胞凋亡率及Bax、Caspase-3、p-YAP/YAP、TAZ表达升高,左室射血分数(LVEF)、左室缩短分数(LVFS)、舒张早期运动速度/舒张晚期运动速度(Em/Am)水平降低(均P<0.05);PD-L组、PD-H组较CHD组心肌细胞形态相对正常,细胞坏死减少,炎性细胞浸润及组织水肿明显减轻,蓝色胶原纤维沉积减少,心肌胶原纤维化面积占比减少,细胞凋亡率及Bax、Caspase-3、p-YAP/YAP、TAZ表达降低,LVEF、LVFS、Em/Am水平升高(均P<0.05);PD-H+PY-60组较PD-H组心肌组织损伤加重,蓝色胶原纤维沉积增多,心肌胶原纤维化面积占比增多,细胞凋亡率及Bax、Caspase-3、p-YAP/YAP、TAZ表达升高,LVEF、LVFS、Em/Am水平降低(均P<0.05)。结论虎杖苷可改善CHD大鼠心肌损伤,其作用机制与抑制Hippo/YAP通路有关。

Objective To investigate the effects of polydatin(PD)on myocardial injury and Hippo-Yes associated protein(YAP)signaling pathway in rats with coronary heart disease(CHD).Methods The CHD rat model was constructed,and the successfully constructed rats were randomly divided into model group(CHD group),polydatin low-dose and high-dose groups(PD-L and PD-H groups),and high-dose polydatin+HiPO-YAP signaling pathway stimulator PY-60 group(PD-H+PY-60 group),with 18 rats in each group.Another 18 normal rats were selected as control group.The ultrasound echocardiography was applied to detect cardiac function.HE staining was applied to observe the pathological morphological changes of myocardial tissue.Masson staining was applied to observe the degree of myocardial fibrosis and the area of collagen fibrosis in rats.TUNEL staining was applied to observe cell apoptosis in myocardial tissue.Western blot was applied to detect the expression of B cell-lymphomatoma-2 associated X protein(Bax),caspase-3,p-YAP/YAP,and transcriptional coactivator with PDZ-binding motif(TAZ).Results Compared with the control group,the CHD group had abnormal myocardial cells,disordered myocardial fiber structure,obvious inflammatory cell infiltration and tissue edema,increased deposition of blue collagen fibers,and an increased proportion of myocardial collagen fibrosis area,the apoptosis rate of cells and the expression of Bax,Caspase-3,p-YAP/YAP,and TAZ increased,the LVEF,LVFS,and Em/Am levels decreased(P<0.05).The morphology of myocardial cells in the PD-L and PD-H groups was relatively normal compared to the CHD group,with reduced cell necrosis,obviously reduced inflammatory cell infiltration and tissue edema,reduced deposition of blue collagen fibers,and reduced proportion of myocardial collagen fibrosis area.The apoptosis rate of cells and the expression of Bax,Caspase-3,p-YAP/YAP,and TAZ reduced,the LVEF,LVFS,and Em/Am levels increased(P<0.05);the PD-H+PY-60 group showed more severe myocardial tissue damage,increased deposition of blue collagen fibers,and increased proportion of myocardial collagen fibrosis area compared to the PD-H group.The apoptosis rate of cells and the expression of Bax,Caspase-3,p-YAP/YAP,and TAZ increased,the LVEF,LVFS,and Em/Am levels decreased(P<0.05).Conclusion Polydatin can improve myocardial injury in CHD rats,and its mechanism of action is related to the inhibition of the Hippo-YAP pathway.