麦冬多糖对转化生长因子-β1诱导心肌细胞凋亡的影响

Effect of ophiopogon japonicus polysaccharide on TGF-β1 induced cardiomyocyte apoptosis

目的探讨麦冬多糖(MDG-1)对转化生长因子(TGF)-β1诱导的心肌细胞活力、凋亡的影响及机制。方法大鼠H9c2心肌细胞分为对照组(不经特殊处理)、TGF-β1组(20ng/ml TGF-β1处理细胞)和MDG-1组(100mg/LMDG-1及20ng/mlTGF-β1处理细胞),噻唑蓝(MTT)及流式细胞术分别检测细胞活力及凋亡率;2′,7′-二氯荧光黄双乙酸盐(DCFH-DA)探针检测活性氧(ROS)水平;Western印迹检测增殖细胞抗原(PCNA)、B淋巴细胞瘤(Bcl)-2、p53、核因子(NF)-κB p65、KB抑制蛋白激酶(IKK)α和β-catenin的蛋白表达。结果与对照组比较,TGF-β1组细胞活力显著降低,PCNA和Bcl-2蛋白表达显著降低,细胞凋亡率显著升高,ROS水平显著升高,p53、NF-κB p65、IKKα和β-catenin蛋白表达显著升高(P<0.05)。与TGF-β1组比较,MDG-1组细胞活力显著升高,PCNA和Bcl-2蛋白表达显著升高,细胞凋亡率显著降低,ROS水平显著降低,p53、NF-κB p65、IKKα和β-catenin蛋白表达显著降低(P<0.05)。结论MDG-1可增强心肌细胞活力,抑制心肌细胞凋亡,其机制可能与降低细胞内ROS水平及抑制Wnt/β-catenin信号和NF-κB信号有关。

Objective To investigate the effect and mechanism of ophiopogon japonicus polysaccharide (MDG-1) on TGF-β1 induced cardiomyocyte viability and apoptosis. Methods H9c2 rat cardiomyocytes were divided into three treatment groups,namely control group (without special treatment),TGF-β1 group (20 ng/ml TGF-β1 treated cells) and MDG-1 group (100 mg/L MDG-1 and 20 ng/ml TGF-β1 treated cells),cell viability and apoptosis rate were detected by MTT and flow cytometry respectively;DCFH-DA probe was used to detect ROS level;Western blot was used to detect the expressions of PCNA,Bcl-2,p53,NF-κB p65,IKKα and β-catenin proteins. Results Compared with that of control group,the cell viability of TGF-β1 group was significantly decreased,the expressions of PCNA and Bcl-2 proteins were significantly decreased,the apoptosis rate,the ROS level,and the expressions of p53,NF-κB p65,IKKα and β-catenin proteins were significantly increased ( P <0.05).Compared with those of TGF-β1 group,the cell viability of the MDG-1 group was significantly increased,the expressions of PCNA and Bcl-2 proteins were significantly increased,the apoptosis rate was significantly decreased,and the ROS level was significantly decreased,the expressions of p53,NF-κB p65,IKKα and β-catenin proteins were significantly decreased ( P <0.05). Conclusions MDG-1 could enhance the activity of cardiomyocytes and inhibit the apoptosis of cardiomyocytes.The mechanism might be related to the decrease of intracellular ROS level and the inhibition of Wnt/β-catenin signal and NF-κB signal.