Objective: To study the dynamic changes in the percentage of Th17 cells/CD4+CD25+ regulatory T cells after intervention with montelukast sodium, a leukotriene receptor antagonist, in asthmatic mice and the association between them.
Methods: Balb/c mice were randomly divided into blank group, asthma group, and montelukast sodium group. The asthmatic mouse model of airway remodeling was established by sensitization with intraperitoneal injection of chicken ovalbumin (OVA) and aluminum hydroxide suspension and aerosol inhalation of OVA. The mice in the blank group were given normal saline, and those in the montelukast sodium group were given montelukast sodium by gavage before aerosol inhalation. Eight mice were randomly sacrificed within 24 hours after 2, 4, and 8 weeks of aerosol inhalation. The pathological sections of lung tissue were used to observe the degree of airway remodeling. Flow cytometry was used to measure the percentages of Th17 cells and CD4+CD25+ regulatory T cells in CD4+ T cells.
Results: The asthma group and the montelukast sodium group had significantly higher bronchial wall thickness and smooth muscle thickness at all time points compared with the blank group (P<0.05). At 8 weeks of intervention, the montelukast sodium group had significantly greater improvements in the above changes compared with the asthma group (P<0.05). Compared with the blank group, the asthma group and the montelukast sodium group had significant increases in Th17 cells (positively correlated with airway remodeling) and significant reductions in CD4+CD25+ regulatory T cells (negatively correlated to airway remodeling) at all time points (P<0.05). At 8 weeks of intervention, the montelukast sodium group had a significant reduction in the number of Th17 cells and a significant increase in the number of CD4+CD25+ regulatory T cells compared with the asthma group (P<0.05).
Conclusions: Montelukast sodium intervention can alleviate airway remodeling and achieve better improvements over the time of intervention. The possible mechanism may be related to the improvement of immunologic derangement of CD4+CD25+ regulatory T cells and inhibition of airway inflammation.
目的: 探讨白三烯受体拮抗剂孟鲁司特钠干预哮喘小鼠后气道重塑及Th17细胞/CD4+CD25+调节性T细胞（CD4+CD25+Treg）表达的动态变化及其相关性。
方法: 将Balb/c小鼠随机分成空白组、哮喘组、孟鲁司特钠组，每组经腹腔注射鸡卵清蛋白（OVA）和氢氧化铝混悬液致敏并雾化吸入2.5％OVA以制备哮喘气道重塑模型，空白组以生理盐水替代；孟鲁司特钠组雾化前给予孟鲁司特钠混悬液灌胃，空白组及哮喘组以生理盐水代替。3组分别在雾化2周、4周及8周后的24h内随机处死8只小鼠。肺组织病理切片观察气道重塑程度；流式细胞技术检测脾组织中Th17、CD4+CD25+Treg细胞占CD4+T细胞百分比。
结果: 各时间点哮喘组和孟鲁司特钠组支气管总管壁厚度、平滑肌厚度均高于空白组（P < 0.05），干预8周时孟鲁司特钠组较哮喘组上述变化明显减轻（P < 0.05）。与空白组比较，各时间点哮喘组和孟鲁司特钠组均显示Th17细胞数增加，与气道重塑呈正相关（P < 0.05）；而CD4+CD25+Treg细胞数逐渐降低，与气道重塑呈负相关（P < 0.05）。干预8周时孟鲁司特钠组与哮喘组比较，Th17细胞数显著下降（P < 0.05）；而CD4+CD25+Treg细胞数明显增加（P < 0.05）。
结论: 孟鲁司特钠干预哮喘小鼠后能减轻气道重塑的发生，且随着用药时间延长，改善越明显；机制可能是通过改善哮喘小鼠体内Th17/CD4+CD25+Treg的免疫紊乱，抑制气道炎症反应从而减轻或延缓气道重塑来起作用的。