丁苯肽对阿霉素诱导心肌损伤的保护作用

Protective effects of 3-N-butylphthalide on doxorubicin-induced myocardial injury

目的研究丁苯酞(3-N-butylphthalide,NBP)对阿霉素(doxorubicin,Dox)诱导心肌损伤的作用,并探讨其可能的作用机制。方法32只雄性SPF级C57小鼠随机分成4组,每组8只,即正常组、NBP组、Dox组、治疗组(Dox+NBP)。Dox组和治疗组小鼠给予Dox 4 mg/kg腹腔注射,每周1次,共注射3周,累积量为12 mg/kg。3周后,治疗组腹腔注射NBP 40 mg/kg,每天1次,连续给药3周。记录各组心脏质量与体质量比值(heart weight/body weight,HW/BW)及心脏超声图,结合HE和Masson染色观测心脏的病理损伤,探究NBP对Dox小鼠心脏功能和心肌损伤的影响。采用免疫印迹法检测各组小鼠心肌NLRP3、Caspase-1蛋白的表达情况。采用MTT法检测不同浓度的Dox(1、5、25和125μmol/L)处理H9C2细胞24 h后H9C2细胞存活率。用含NBP(2、10和50μg/mL)的培养液与Dox(5μmol/L)所致H9C2细胞损伤共孵育24 h,MTT法检测H9C2细胞存活率;Western blot检测NLRP3表达和Cas‐pase1切割体的含量。结果与正常组比较,Dox组小鼠心肌纤维排列紊乱,心肌纤维化明显;左心室收缩末期内径和舒张末期内径均显著增大(P<0.05),左心室射血分数和短轴缩短率、HW/BW明显减少(P<0.05);心肌组织NLRP3蛋白表达和Caspase-1水解切割明显增多(P<0.05)。与Dox组比较,治疗组小鼠心功能和心肌损伤检测指标均得到有效改善(P<0.05);心肌组织NLRP3蛋白表达、Caspase-1水解切割明显减少(P<0.05)。Dox(1、5、25和125μmol/L)显著抑制H9C2细胞存活率(P值均<0.05)。NBP(10和50μg/mL)共处理可显著抑制Dox(5μmol/L)对H9C2细胞的毒性作用,且NBP(50μg/mL)显著减少Dox致NLRP3表达和Caspase-1水解切割增多(P<0.05)。结论NBP对Dox所致小鼠心肌损伤具有一定的保护作用,其可能的作用机制是抑制心肌细胞NLRP3炎症小体的激活。

Objective To study the effect of 3-N-butylphthalide(NBP)on doxorubicin(Dox)-induced cardiotoxicity in mice and its possible mechanism.Methods Thirty-two C57 mice were randomly divided into 4 groups,eight in each group:control group,NBP group,Dox group and treatment group(Dox+NBP).Dox(4 mg/kg)was injected intraperitoneally once a week for 3 weeks,with a cumulative amount of 12 mg/kg.After 3 weeks,NBP(40 mg/kg)was injected intraperitoneally once a day for 3 weeks.The effect of NBP on myocardial injury and cardiac function in Dox-injected mice were investigated by recording the heart weight/body weight(HW/BW)and echocardiogram of mice,and observing the heart tissue by HE and Masson staining.Western blots were used to detect the expression of NLRP3 and Caspase-1 protein in myocardium of Dox mice by NBP treatments.MTT assay was used to analyze the effect of different concentrations of NBP on the survival rate of H9C2 cells induced by Dox.Western blots were used to detect the expression of NLRP3 and Caspase-1 protein in Dox(5μmol/L)-induced H9C2 cells with or without 50μg/mL NBP co-treatments.Results Compared with the control group,the myocardial fibers in the model group were disordered and the myocardial fibrosis was obvious.Left ventricular end-systolic diameter and left ventricular end-diastolic diameter were significantly increased(P<0.05),ejection fraction,fractional shortening,and HW/BW were significantly decreased(P<0.05).The expression of NLRP3 protein and the cleaved Caspase-1 in myocardium increased significantly(P<0.05).Above indexes were effectively improved by the treatment of NBP.Compared with the control group,the survival rate of H9C2 cells in the model group decreased significantly(P<0.05).Compared with the control group,the survival rate of H9C2 cells in the model group was significantly decreased(P<0.05);and NLRP3 protein expression and cleaved Caspase-1 in H9C2 cells were significantly increased(P<0.05).Compared with the model group,the cell survival rate was increased(P<0.05);and NLRP3 protein expression and cleaved Caspase-1 were decreased in the treatment group(P<0.05).Conclusion NBP is protective against Dox-induced myocardial injury,and its possible mechanism may be relevant to the reduced NLRP3 inflammasome activation.