基于miR-378探讨丹红注射液干预压力超负荷心力衰竭大鼠心肌纤维化机制

Mechanism of Danhong Injection on the myocardial fibrosis of heart failure rats with stress overload based on miR-378

目的探讨丹红注射液对压力超负荷心力衰竭大鼠心肌纤维化的作用与机制。方法取50只大鼠并对其行主动脉弓缩窄术(transverse aortic constriction,TAC),造模9周后将其随机分为模型(TAC)组、丹红注射液(DH)组(6.0 mL·kg-1)、卡托普利(Captopril)组(8.8 mg·kg-1),另设立10只为假手术(Sham)组。药物干预15 d后对各组大鼠进行超声心动图检测;酶联免疫法测定血清氨基末端脑钠肽前体(N-terminal pro brain natriuretic peptide,NT-pro BNP)含量;HE、Masson染色观察心肌病理学及纤维化改变,Western blot检测心肌组织中转化生长因子β1(transforming growth factor-β1,TGF-β1)、Ⅰ型胶原蛋白(collagen-1,COL-1)、Ⅲ型胶原蛋白(collagen-3,COL-3)及α平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)表达;qRT-PCR检测心肌组织中miR-378、TGF-β1 mRNA、Col-1 mRNA、Col-3 mRNA、ɑ-SMA mRNA表达。结果与Sham组比较,TAC组左室射血分数(left ventricular ejection fraction,LVEF)和左室短轴缩短率(left ventricular fractional shortening,LVFS)、心肌组织miR-378下降,左室舒张末期内径(left ventricular end diastolic dimension,LVEDD)、左室收缩末期内径(left ventricular end systolic diameter,LVESD)、血浆NT-pro BNP、TGF-β1、COL-1、COL-3及α-SMA mRNA及蛋白表达升高,差异均有统计学意义(P<0.01);细胞排列紊乱,纤维化明显。与TAC组比较,DH组LVEF、LVFS、心肌组织miR-378上升,LVEDD、LVESD、血浆NT-pro BNP、TGF-β1、COL-1、COL-3及α-SMA mRNA及蛋白表达下降,差异均有统计学意义(P<0.01);细胞排列趋于整齐,胶原纤维沉积减轻。结论丹红注射液能够改善压力超负荷心力衰竭大鼠心肌纤维化,其机制与调控miR-378/TGFβ-1信号通路表达有关。

Objective To investigate the effect and mechanism of Danhong Injection (DHI) on myocardial fibrosis in heart failure rats with stress overload.Methods Fifty rats received transverse aortic constriction (TAC),and after 9 weeks of modeling,they were randomly divided into model (TAC) group,Danhong Injection (DHI) group (6.0 mL·kg-1),Captopril (8.8 mg·kg-1) group.And another 10 rats were set as the sham-operated group.After 15 days of intervention,echocardiogram detection was performed on rats in each group.Serum N-terminal pro brain natriuretic peptide (NT-pro BNP) content was determined by enzyme-linked immunoassay;myocardial pathology and fibrotic change was observed by HE and Masson staining;transforming growth factor-β1 (TGF-β1),collagen-1 (COL-1),collagen-3 (COL-3) and α smooth muscle act (α-SMA) expression of myocardial tissue was detected by Western blot;the expression of miR-378,TGF-β1 mRNA,Col-1 mRNA,Col-3 mRNA,and α-SMA mRNA of myocardial tissue was detected by qRT-PCR.Results Compared with the sham-operated group,the left ventricular ejection fraction (LVEF),the left ventricular fractional shortening rate (LVFS),and miR-378 of myocardial tissue in the TAC group decreased;the left ventricular end-diastolic diameter (LVEDD),the left ventricular end systolic diameter (LVESD),plasma NT-pro BNP,TGF-β1,COL-1,COL-3,α-SMA m RNA and protein expression were significantly higher (P<0.01);disordered arrangement of the cells and obvious fibrosis was shown.Compared with TAC group,the expression of LVEF,LVFS and miR-378 of myocardial tissue increased,and the LVEDD,LVESD,plasma NT-pro BNP,TGF-β1,COL-1,COL-3,α-SMA mRNA and protein expression decreased significantly in DHI group(P<0.01);cell arrangement tended to be neat,and the deposition of collagen fibers was reduced.Conclusion DHI can reduce myocardial fibrosis in heart failure rats with stress overload,and its mechanism is related to the expression regulation of miR-378/TGFβ-1 signaling pathway.