【摘要】 目的探讨转化生长因子-β(TGF-β)对肥胖哮喘小鼠气道重塑的影响及吡非尼酮干预的作用。方法 75只C57BL/6J小鼠随机分为对照组(A组)、肥胖组(B组)、肥胖哮喘组(C组)、布地奈德治疗组(D组)、吡非尼酮治疗组(E组)5组,每组15只。肥胖小鼠以高脂饮食诱导肥胖模型,C、D、E组采用卵清蛋白致敏激发建立哮喘模型,对照组以普通饲料饲养,生理盐水致敏激发。D组以布地奈德悬液(0.5 mg/ml)雾化,E组以吡非尼酮(300 mg/kg)饮水干预,余组正常饮水。4周后收集支气管肺泡灌洗液(BALF)进行细胞计数及分类。肺组织切片观察小鼠气道炎症及重塑情况,测定气管壁总面积(WAt)、气管平滑肌面积(WAm)和管腔基底膜周长(Pbm)。采用酶联免疫吸附实验、蛋白质印迹法检测TGF-β水平。结果 C组小鼠BALF中白细胞总数、嗜酸性粒细胞百分比、TGF-β水平、气管壁厚度(WAt/Pbm)和平滑肌厚度(WAm/Pbm)均高于其他四组;E组BALF中嗜酸性粒细胞百分比、WAt/Pbm较D组减少(P均<0.05);TGF-β水平按照C、D、E、B、A组依次递减(P均<0.05),且与BALF中嗜酸性粒细胞百分比呈正相关(r=0.79,P均<0.01)。结论 TGF-β在肥胖哮喘小鼠气道中高表达,与气道重塑有密切关系。吡非尼酮能有效抑制TGF-β的表达,从而改善肥胖哮喘气道重塑。更多还原

【Abstract】 Objective To investigate the effects of transforming growth factor beta(TGF-β) on airway remodeling in obese asthmatic mice and intervention effects of pirfenidone. Methods Seventy-five C57BL/6J mice were randomly divided into five groups, namely a blank control group(group A), an obese group(group B), an obese asthmatic group(group C), a budesonide treatment group(group D) and a pirfenidone treatment group(group E). The mice in the B, C, D, and E groups were fed with high fat diets, then the mice in the C, D, and E groups were sensitized and challenged with ovalbumin(OVA) to establish the model of chronic obese asthma. The mice in group A were fed with normal diets,sensitized and challenged with normal saline. The mice in group D were treated with budesonide(0.5 mg/ml), and the mice in group E were treated with pirfenidone(300 mg/kg). After 4 weeks of treatment, the total number of white cells as well as the percentage of leukocytes, eosinophils, neutrophils and macrophage in bronchoalveolar lavage fluid(BALF)were counted. ELISA and Western blot were used to evaluate the expression of TGF-β. The pathological changes of mice were observed under light microscope by HE and periodic acid-Schiff staining. Meanwhile the remodeling indices were measured including total bronchial wall area(WAt), smooth muscle area(WAm), and bronchial basement membrane perimeter(Pbm). Results The levels of leukocyte and eosinophils in BALF, expression of TGF-β, WAt/Pbm and WAm/Pbm in group C were higher than those in group A, B, D, and E(all P<0.05). The levels of eosinophils in BALF,WAt/Pbm in group E were lower than those in group D(all P<0.05). The level of TGF-β decreased in a sequence of group C>D>E>B>A(all P<0.05). The expression of TGF-β was in a positive correlation with eosinophil percentage in BALF(r=0.79, P<0.01). Conclusions The expression of TGF-β in the airway of obese asthmatic mice is closely related to airway inflammation, airway hyper-secretion and airway remodeling. Pirfenidone can effectively inhibit the expression of TGF-βand improve airway remodeling.更多还原