天龙咳喘灵改善慢性哮喘小鼠气道重塑的机制

The Mechanism of Tianlongkechuanling (TLD) Ameliorating Airway Remodeling in Chronic Asthma in Mice

目的:探讨中药验方天龙喘咳灵水煎剂干预支气管哮喘气道重塑的可能机制。方法:实验设3组,盐水对照组,哮喘模型组,天龙咳喘灵治疗组。小鼠经常规OVA致敏后连续18天给予1.5%的OVA雾化吸入激发。治疗组小鼠每次激发后给予雾化天龙咳喘灵水煎剂。末次激发后72h,利用气道插管检测各组小鼠气道反应性;肺泡灌洗,观察肺泡灌洗液(BALF)中细胞总数和细胞分类;分离小鼠右肺制备组织切片进行病理分析;分离小鼠左肺提取总蛋白,检测肺部α-SMA表达水平和丝裂原活化蛋白激酶(mitogen activatedprotein,MAPK)信号通路,信号传导及转录活化因子-3(signal transducers and activators of transcription-3,Stat3)的活化情况。结果:与盐水对照组相比,OVA-哮喘组小鼠气道反应性显著升高(P<0.01),相应BALF中细胞总数和嗜酸性粒细胞比例也明显增加(P<0.01);天龙咳喘灵治疗组小鼠气道反应性明显低于哮喘组小鼠(P<0.01),但BALF中细胞总数和嗜酸性粒细胞比例亦较正常对照组增加(P<0.01)。肺组织病理切片显示哮喘组上皮下基底膜层明显增厚,α-SMA表达水平增高,而天龙咳喘灵治疗组气道上皮下未见明显改变,α-SMA表达水平与盐水对照组无显著差别。在哮喘小鼠肺部,MAPKs信号通路当中的胞外信号调节激酶(extracellular signal-reg-ulated kinase,ERK)通路和Stat3通路明显激活,而天龙咳喘灵能有效抑制该信号途径的活化。结论:天龙喘咳灵水煎剂能有效防治慢性哮喘小鼠模型的气道重塑,其机制可能是通过抑制ERKs通路和Stat3通路的活化实现的。

Objective：To understand the mechanism whereby Tianlong Decoction（TLD）,a traditional Chinese medicine prescription attenuated airway remodeling in asthma.Methods：OVA-sensitized BALB/c mice were challenged by OVA inhalation for 18 days and treated by aerosol saline or TLD respectively after each OVA challenge.Airway reactivity（AR） was assessed 72 hrs after the last challenge followed by bronchoalveolar lavage（BAL）.Histopathologic examination was performed with HE staining.The expression of α-smooth muscle actin（α-SMA） in lungs,together with the activation of MAPKs and Stat3 were assayed by western blot.Results：A markedly enhanced AR was detected in the OVA-challenged mice,along with an increase in total cells and EOS count in the BALF.The AHR was not observed in the TLD-treated mice in which total cells and EOS count increased as well.The thickening basement membrane,accompanied by an over-expression of α-SMA,phosphorylated ERKs and Stat3 in lungs were found in asthmatic mice rather than in TLD-treated mice.Conclusion：TLD has the capability to treat and prevent the asthmatic airway remodeling,the effect of which is related to its action on down-regulating the levels of phosphorylated ERKs and Stat3.