补肺活血胶囊对慢性阻塞性肺疾病模型大鼠气道重塑的干预作用及机制研究

目的基于转化生长因子-β1(transforming growth factor-β1,TGF-β1)/Smads信号通路及蛋白酶与抗蛋白酶系统,探讨补肺活血胶囊对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)模型大鼠气道重塑的作用机制。方法将40只SPF级Wistar大鼠随机分为正常对照组、模型组、补肺活血组和茶碱组。采用香烟烟雾暴露复合气道内滴注脂多糖的方法复制COPD动物模型;实验自第21天起,补肺活血组予补肺活血胶囊0.42 g/kg,茶碱组予茶碱缓释片0.02 g/kg,连续给药40 d。实验第61天取血后处死大鼠,取肺组织制作病理切片观察其病理学改变及气道胶原沉积情况,检测肺组织TGF-β1、Smad2/3、Smad4、Smad7蛋白和嗜中性粒细胞弹性蛋白酶(neutrophil elastase,NE)、α1-抗胰蛋白酶(α1-antitrypsin,α1-AT)、基质金属蛋白酶-9(matrix metalloproteinase 9,MMP-9)、金属蛋白酶组织抑制因子-1(tissue inhibitor of metalloproteinases 1,TIMP-1)的表达水平。结果与正常对照组比较,模型组大鼠气道上皮增厚,炎症细胞浸润,细胞外基质沉积,基底膜增厚,肺泡结构破坏,肺泡融合,肺泡间隔增厚,胶原纤维沉积明显;肺组织TGF-β1、Smad2/3、Smad4、NE、α1-AT、MMP-9、TIMP-1蛋白表达水平升高(P<0.05),Smad7表达水平降低(P<0.05)。与模型组比较,补肺活血组与茶碱组炎症细胞浸润减轻,胶原纤维沉积显著减少;肺组织TGF-β1、Smad2/3、Smad4、NE、α1-AT、MMP-9、TIMP-1蛋白表达水平降低(P<0.05),Smad7表达水平升高(P<0.05)。与茶碱组比较,补肺活血组各指标均未见显著差异(P>0.05)。结论补肺活血胶囊可以通过调节TGF-β1/Smads信号通路、蛋白酶与抗蛋白酶平衡干预COPD模型大鼠气道重塑。

Intervention Effect of Bufei Huoxue Capsule on Airway Remodeling in A Rat Model of Chronic Obstructive Pulmonary Disease and Its Mechanism

Objective To investigate the mechanism of action of Bufei Huoxue Capsule on airway remodeling in a rat model of chronic obstructive pulmonary disease(COPD)based on the TGF-β1/Smads signaling pathway and the protease-antiprotease system.Methods A total of 40 specific pathogen-free Wistar rats were randomly divided into normal control group,model group,Bufei Huoxue group,and theophylline group.An animal model of COPD was established by cigarette smoking exposure combined with intra-airway dripping of lipopolysaccharide;since day 21 of the experiment,the rats in the Bufei Huoxue group were given Bufei Huoxue Capsule 0.42 g/kg,and those in the theophylline group were given theophyllinesustained-release tablets 0.02 g/kg for 40 consecutive days.On day 61 of the experiment,the rats were sacrificed after blood samples were collected,and lung tissue was harvested for pathological section to observe pathological changes and airway collagen deposition,as well as for measuring the protein expression levels of transforming growth factor-β1(TGF-β1),Smad2/3,Smad4,Smad7,neutrophil elastase(NE),α1-antitrypsin(α1-AT),matrix metalloproteinase-9(MMP-9),and tissue inhibitor of metalloproteinase-1(TIMP-1)in lung tissue.Results Compared with the normal control group,the model group had thickening of the airway epithelium,inflammatory cell infiltration,extracellular matrix deposition,thickening of the basilar membrane,destruction of alveolar structure,alveolar fusion,thickening of the alveolar septa,and marked deposition of collagen fibers,as well as significant increases in the protein expression levels of TGF-β1,Smad2/3,Smad4,NE,α1-AT,MMP-9,and TIMP-1(P<0.05)and a significant reduction in the protein expression level of Smad7(P<0.05).Compared with the model group,the Bufei Huoxue group and the theophylline group had significant reductions in inflammatory cell infiltration and deposition of collagen fibers,as well as significant reductions in the protein expression levels of TGF-β1,Smad2/3,Smad4,NE,α1-AT,MMP-9,and TIMP-1(P<0.05)and a significant increase in the protein expression level of Smad7(P<0.05).There were no significant differences in the above indices between the Bufei Huoxue group and the theophylline group(P>0.05).Conclusion Bufei Huoxue Capsule exerts an intervention effect on airway remodeling in the rat model of COPD by regulating the TGF-β1/Smads signaling pathway and the protease-antiprotease balance.