氧化苦参碱对TGF-β_1诱导心肌细胞损伤的保护作用

Protective Effect of Oxymatrine on Cardiomyocyte Injury Induced by TGF-β_1

目的:探讨氧化苦参碱(OMT)对转化生长因子-β_1(TGF-β_1)诱导的新生SD乳鼠心肌细胞损伤的保护作用及机制。方法:胰酶消化差速贴壁法分离纯化SD乳鼠原代心肌细胞。实验分为4组,包括正常组,模型组[转化生长因子-β_1(TGF-β_1),20×10-5g·L^(-1)],OMT高剂量组(TGF-β_1+0.1 g·L^(-1)OMT),OMT低剂量组(TGF-β_1+0.05 g·L^(-1)OMT)。OMT预保护2 h后,采用TGF-β_1孵育48 h建立心肌细胞损伤模型。利用噻唑蓝(MTT)法检测细胞存活率,生化法检测乳酸脱氢酶(LDH)外漏量,蛋白质免疫印迹法(Western blot)检测p38,细胞外信号调节蛋白激酶(ERK),c-Jun氨基末端激酶(JNK)蛋白的表达水平。结果:TGF-β_1显著引起心肌细胞损伤,OMT(0.1,0.05 g·L^(-1))能够抑制TGF-β_1诱导的心肌细胞存活率下降及LDH外漏量增加。OMT高剂量组(0.1 g·L^(-1))可下调TGF-β_1诱导的心肌细胞p-p38,p-ERK1/2,p-JNK的蛋白表达,但对p38,JNK,ERK1/2总蛋白表达无影响。结论:OMT对TGF-β_1诱导的心肌细胞损伤具有保护作用,其机制与其抑制p38,ERK1/2,JNK蛋白的磷酸化有关。

Objective： To investigate the protective effect of oxymatrine （OMT） on rat primary cardiomyocyte injury induced by transforming growth factor-β1 （TGF-β1 ） , and explore its mechanism. Method： Primary cardiomyocytes of SD neonatal rats were isolated by trypsin digestion method and purified by differential adhesion method. The cardiomyocytes was divided into four groups, such as the normal group, model group （TGF-β1, 20 × 10-5 g·L^-1）, OMT high-dose group （TGF-β1 ＋ 0. 1 g·L^-1 OMT） and OMT low-dose group （TGF-β1 ＋ 0.05 g·L^-1OMT）. After being preincubated with OMT for 2 h, and then TGF-β1 was added to establish myocardial cell injury model by cocuhure for 48 h. MTT method was adopted to detect cell viability, and the external leakage of lactate dehydrogenase was analyzed by biochemical method, Western blot was used to detect p38, extracellular signal-regulated protein kinases （ERK） and c-Jun N-terminal kinase （JNK） protein expression levels. Result： TGF-β1 significantly induced cardiomyocyte injury, cardiomyocyte viability decrease and LDH leakage increase were significantly attenuated by OMT with dose of 0. 1, 0. 05 g·L^-1 OMT （0. 1 g·L^-1） could inhibit the expression of p-p38, p-JNK, p-ERK1/2 in myocardium induced by TGF-β1; but it had no effect on total protein expression of p38, JNK and ERK1/2. Conclusion： OMT has protective effect on cardiomyocyte injury induced by TGF-β1, and its mechanism may be involved in inhibiting phosphorylation of p38, ERK1/2 and JNK protein.