早期吸入糖皮质激素对哮喘大鼠气道重建及IGF-1表达的影响

Effects of early inhaled corticosteroids on airway remodeling and expression of insulin-like growth factor-1 in asthma rats

目的 研究早期吸入糖皮质激素对气道重建及胰岛素样生长因子 1 (IGF 1 )表达的影响。方法 将 30只大鼠分为对照组、哮喘组和地塞米松治疗组。免疫组织化学技术检测气道壁IGF 1的表达 ,计算机图像分析技术对气道壁IGF 1的表达进行定量分析及测量小气道内周长和厚度 ,并观察嗜酸性粒细胞浸润情况。结果 IGF 1的表达水平、嗜酸性粒细胞数、气道壁厚度哮喘组显著高于对照组 (P <0 .0 5 ) ;治疗组显著低于哮喘组 (P <0 .0 5 ) ;但与对照组相比仍较高 (P <0 .0 5 ) ;IGF 1的表达水平与气道壁厚度正相关。结论 哮喘时气道壁增厚 ,气道重建 ,IGF 1的表达增加 ,早期糖皮质激素治疗可减轻气道壁厚度增加 ,减少IGF 1的表达。

Objective To investigate the effects of early inhaled corticosteroids on airway remodeling and the expression of insulin like growth factor 1(IGF 1) in asthma rats.Methods Thirty rats were randomly divided into three groups: control group, asthma group and therapeutic group with inhaled dexamethasone. The expression of IGF 1 in lung tissue was observed by immunohistochemical staining. With computer image analysis system, we detected the airway expression of IGF 1, the thickness of airway wall, and the number of eosinophils.Results The expression of IGF 1, the thickness of airway wall and the number of eosinophils were significantly higher in asthma group than those of control group ( P <0.05); it was much lower in the therapeutic group than that in asthmatic one ( P <0.05), but it still was higher than the control ( P <0.05).So there was a positive relationship between level of expression of IGF 1 and the thickness of airway wall.Conclusion These results suggest that the treatment with early inhaled corticosteroids in asthma can reduce the thickness of the airway wall by modulation of IGF 1 expression with consequent inhibition of the airway infiltration by inflammatory cells, and therefore may help to prevent remodeling of the airway.