γ-分泌酶抑制剂在哮喘小鼠模型Th17/Treg平衡失调中的作用

Role of γ-secretase inhibitor in the imbalance of Th17/Treg in a mouse asthmatic model

目的研究γ-分泌酶抑制剂DAPT对哮喘气道炎症、气道高反应和Th17/Treg失衡的干预作用,为其抗哮喘活性制剂的研究与开发提供理论依据。方法 6-8周雌性C57BL/6小鼠45只被随机分为对照组,哮喘组和DAPT组,每组15只苏木精-伊红(HE)染色法观察气道病理改变,酶联免疫吸附法检测小鼠支气管肺泡灌洗液(BALF)中细胞因子和炎性介质的水平,逆转录聚合酶链反应法(RT-PCR)分析脾脏Foxp3 mRNA的表达。结果 DAPT组较哮喘组气道炎症明显减轻,气道内黏液分泌显著减少。哮喘组IgE、IL-17、IL-10和TGF-β1的含量分别为(695±148)ng/ml,(58±6)pg/ml,(148±12)pg/ml,(18±3)pg/ml;DAPT组IgE、IL-17、IL-10和TGF-β1的含量分别为(486±152)ng/ml,(27±6)pg/ml,(193±17)pg/ml,(33±5)pg/ml。与哮喘组比较,DAPT组气道灌洗液中IL-17、IgE水平显著降低(P<0.01),IL-10、TGF-β1水平显著增加(P<0.01),Foxp3 mRNA的表达也显著增加(P<0.01)。结论γ-分泌酶抑制剂DAPT具有抗哮喘小鼠Th17/Treg失衡的作用。

Objective To explore the effects of γ-secretase inhibitor（ DAPT） on the airway inflammation,the airway hyperactivity and the imbalance of Th17/Treg in a mouse model of allergic asthma for providing a theoretical basis for the research and development of anti-asthma activity preparations. Methods Forty-five female C57BL/6 mice were randomly divided into 3 groups： control group,asthma group and DAPT group. The pathological changes of lung tissue were analyzed by hematoxylin-eosin staining. Levels of cytokine and inflammatory mediators in bronchoalveolar lavage fluid（ BALF） were measured by enzyme-linked immunosorbent assay. The expression of Foxp3 mRNA in spleen was detected by reverse transcription polymerase chain reaction（ RT-PCR）. Results The airway inflammation and mucus secretion were alleviated in DAPT group compared with asthma group. The contents of IgE,IL-17,IL-10 and TGF-β1in asthma group were（ 695±148） ng/ml,（ 58±6） pg/ml,（ 148±12） pg/ml,（ 18± 3） pg/ml,respectively. The contents of IgE,IL-17,IL-10 and TGF-β1in DAPT group were（ 486±152） ng/ml,（ 27±6） pg/ml,（ 193±17） pg/ml,（ 33±5） pg/ml,respectively. Compared with asthma group,the levels of IgE and IL-17 were significantly decreased in DAPT group（ P〈0. 01）,the levels of IL-10,TGF-β1and the expression of Foxp3 mRNA were significantly increased in DAPT group（ P〈0. 01）. Conclusion The γ-secretase inhibitor DAPT may efficiently regulate the imbalance of Th17/Treg to balance a mouse asthmatic model.