摘要目的 研究Wnt2、β-catenin蛋白在多柔比星(DOX)诱导心肌损伤中的表达情况,探讨Wnt2、β-catenin分子在DOX损伤心肌细胞凋亡中的作用.方法 将不同质量浓度(1 mg/L、2 mg/L、3 mg/L、4 mg/L)DOX处理心肌细胞72 h后,用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法检测不同质量浓度DOX对心肌细胞生长曲线的影响.用1 mg/L DOX建立心肌细胞损伤模型,将心肌细胞分为4组,A组:DOX损伤心肌细胞12 h;B组:DOX损伤心肌细胞24 h;C组:DOX损伤心肌细胞48 h;D组:正常心肌细胞.利用蛋白印迹法(Western blot)、实时反转录聚合酶链反应(RT-PCR)法分别检测各组细胞中Wnt2、β-catenin、p53蛋白及mRNA的表达变化.结果 DOX抑制对心肌细胞的增殖具有浓度依赖性;Wnt2蛋白和mRNA的表达在DOX各组中表达水平均高于D组,差异有统计学意义(F =224.115,P＜0.05);β-catenin、p53蛋白在DOX各组中的表达水平显著高于D组,且随时间的延长,表达程度越高,差异均有统计学意义(F=188.145、231.927,P均＜0.05);β-catenin与p53呈正相关(r=0.940,P＜0.05).结论 Wnt2、β-catenin可能在DOX诱导的心肌细胞损伤中起着重要的作用,为进一步探讨心肌细胞损伤的分子机制提供了重要依据.

abstractsObjective To investigate the expressions of Wnt2 and β-catenin in Doxorubicin (DOX)-induced myocardial injury and to explore their roles in myocardial cell apoptosis.Methods Cardiomyoblast cells were damaged by different concentrations of DOX(1 mg/L,2 mg/L,3 mg/L,4 mg/L) for 72 h.The effect of different concentrations of DOX on cardiomyocyte growth curve was detected according to the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-h-tetrazolium bromide(MTT) assay.DOX(1 mg/L) was used to induce the model of cardiomyoblast cell injury.Cardiomyocytes were divided into 4 groups:group A:DOX-injured cardiomyocytes for 12 h ;group B:DOX-injured cardiomyocytes for 24 h ; group C:DOX-injured cardiomyocytes for 48 h; group D:normal cardiomyocytes.The expressions of Wnt2,β-catenin and p53 were observed by Western blot and reverse transcription polymerase chain reaction(RT-PCR) at the time point of 12 h,24 h and 48 h.Results DOX significantly inhibited cardiomyocyte proliferation in a dose dependent fashion.The protein and mRNA expressions of Wnt2 increased in the DOX-induced myocardial injury group compared with the group D,with statistical significance (F =224.115,P ＜ 0.05) ;The expressions of β-catenin,p53 were significantly increased compared with the group D,and the higher expression appeared with the time extending(F =188.145,231.927,all P ＜ 0.05).Significantly positive correlation between Wnt2 and β-catenin expression was observed(r =0.940,P ＜ 0.05).Conclusions These findings suggest that Wnt2/β-catenin signaling pathway may play important roles in the cardiovascular disease and be useful for exploring the molecular mechanism of myocardial injury..