天龙咳喘灵对慢性哮喘小鼠气道重塑的影响

The anti-remodeling effect of tianlong decoction(TLD)in a murine model of chronic asthma

目的探讨中药验方天龙咳喘灵水煎剂治疗哮喘气道高反应的可能机制。方法实验设四组,盐水对照组,哮喘模型组,天龙咳喘灵治疗组和布地奈德(BUD)治疗组。小鼠经常规鸡卵清蛋白(OVA)致敏后连续18d给予1%的OVA雾化吸入激发。末次激发后24h和96h,利用体积描记仪动态观察各组小鼠气道反应性,24h-时间点取部分小鼠进行肺泡灌洗,观察肺泡灌洗液(BALF)中细胞总数和细胞分类,剩余小鼠完成96h-时间点气道反应性检测后与上述同样处理,并分离小鼠右肺制备组织切片进行病理分析。结果末次激发后24h或96h,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中细胞总数和嗜酸粒细胞比例也明显增加;天龙咳喘灵治疗组小鼠在24h时间点气道反应性较未治疗哮喘组无明显差别,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),但在激发后96h气道反应性基本回到正常水平;相比之下,BUD治疗组小鼠在24h时间点气道反应性显著低于哮喘组或天龙咳喘灵治疗组(P<0.01),但却在96h后气道反应性反弹上升,显著高于正常对照及天龙咳喘灵治疗组(P<0.01),此时各组细胞总数和嗜酸粒细胞比例均已明显下降,且BUD治疗组仍低于天龙咳喘灵治疗组(P<0.01)。肺组织病理切片显示哮喘组和BUD治疗组上皮下基底膜层明显增厚,α-SMA免疫染色显著增强,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。结论不同于表面激素的抗炎效应,天龙咳喘灵水煎剂能有效防治慢性哮喘小鼠模型气道高反应性,可能主要是通过抑制肌纤维母细胞激活的抗重构作用机制。

Objective To understand the mechanism whereby Tianlong Decoction(TLD),a traditional Chinese medicine prescription treats airway hyperresponsiveness(AHR)in asthma.Methods OVA-sensitized BALB/c mice were challenged by OVA inhalation for 18 days and the mice were treated by aerosol saline,TLD or budesonide(BUD)respectively after each OVA challenge.Airway reactivity(AR)was assessed 24 h or 96 h after the last challenge,using whole body plethysmography followed by bronchoalveolar lavage(BAL).The expression of α-smooth muscle actin(α-SMA)in lungs was assayed by immunohistochemisty.Results A markedly enhanced AR was detected in the OVA challenged mice accompanied by an increase in total cell and EOS count in the BALF 24 h or 96 h after the last challenge,the enhanced AR was also observed in the OVA challenged mice with the treatment of TLD 24 h but not 96 h after the challenge.In contrast,in the mice of BUD-treated group,the OVA induced AHR was detected 96h after the challenge where the number of EOS had been decreased significantly.The thickening basement membrane was found in asthmatic mice and those treated with BUD,but not TLD-treated mice.The immuno-staining showed an over-expression of α-SMA in the lungs of asthmatic mice or those treated with BUD,but not TLD-treated mice.Conclusion We demonstrate that TLD has the ability to down-regulate AHR by treating airway remodeling.