罗红霉素对哮喘大鼠NF-κB及气道炎症的影响

Effects of roxithromycin on NF-κB activity and bronchial hyperresponsiveness of asthma rats

目的:观察罗红霉素对哮喘大鼠NF-κB、气道炎症、气道高反应性的影响。方法:30只雄性SD大鼠随机分成正常对照组(C组)、哮喘组(A组)、罗红霉素组(R组),每组10只。用卵白蛋白(OVA)制备哮喘大鼠模型。各组大鼠在末次激发后24 h,检测气道反应性后放血处死;ELISA测定支气管肺泡灌洗液(BALF)中的IL-4、IL-5、IFN-γ的浓度;免疫组化检测支气管上皮NF-κB p65活化。结果:哮喘组大鼠气道反应性高于对照组(P<0.01),罗红霉素组与哮喘组比较气道反应性下降(P<0.05);BALF中IL-4、IL-5,哮喘组含量均高于对照组(P<0.01),罗红霉素组均低于哮喘组(P<0.01),罗红霉素组BALF中IFN-γ低于对照组(P<0.01)但高于哮喘组;哮喘组大鼠支气管上皮NF-κB蛋白的活化明显高于对照组,罗红霉素组低于哮喘组(P<0.01)。支气管上皮NF-κB p65活化与BALF中的IL-4、IL-5的含量呈显著正相关(r=0.856,P<0.01;r=0.912,P<0.01);大鼠BALF中的IL-4、IL-5的含量与Raw增加25%时(PC25Raw)呈显著负相关(r=-0.713,P<0.01;r=-0.772,P<0.01),与Cdyn下降15%时(PC15Cdyn)呈显著负相关(r=-0.738,P<0.01;r=-0.818,P<0.01)。结论:罗红霉素可能部分通过抑制NF-κB活性而纠正哮喘Th1/Th2细胞因子失衡,罗红霉素降低哮喘大鼠的气道反应性可能和减少IL-4、IL-5的表达有关。

AIM： To investigate the effect of roxithromyein on the NF-κB activity, the airway inflammation and bronchial hyperresponsiveness of asthma rats.METHODS： Thirty male adult Sprague-Dawley rats were randomly divided into the control group（Group C, n = 10）, asthma group （Group A, n = 10） and roxithromycin group（Group R, n = 10）. The asthma mod- el was induced by ovalbumin and Al（OH）3 . The airway reactivity was detected and then rats in each group were sacrificed after 24 hours for the last provocation. The concentrations of IL-4, IL-5 and IFN-γ in bronchoalveolar lavage fluid （BALF） were measured by ELISA, and the activity of NF-κB protein in bronchial epithelium was detected by immunohistochemistry. RESULTS： Compared with Group C, the airway reactivity in Group A was increased（ P 〈 0.01 ）. Compared with Group A, the airway reactivity in Group R was decreased （P 〈 0.05）. Compared with Group A, the concentrations of IL-4, IL-5 in BALF in Group C were decreased （all P 〈 0.01 ） and those in Group R were decreased （all P 〈 0.01）. The concentration of IFN-γ in BALF in Group R was significantly less than that in Group C （ P 〈 0.01 ） but was higher than that in Group A （ P 〈 0.01）. The activity of NF-κB protein in bronchial epithelial in Group A was significantly higher than that in Group C （ P 〈 0.01 ） and that in Group R was less than that in Group A （P 〈 0.01 ）. There were significantly positive correlation between the activity of NF-κB p65 in bronchial epithelium and the concentrations of IL-4, IL-5 in BALF （ r = 0. 856, P 〈 0.01 ; r = 0.912 , P 〈 0.01）. There were significantly negative correlation between the concentrations of IL-4 and IL-5 in BALF and PC25Raw and PC15Cdyn （ r = - 0. 713, P〈0.01; r=-0.772, P〈0.01,r=-0. 738, P〈0.01; r=-0.818, P〈0.01, respectively）. CONCLUSION： Roxithromycin can significantly inhibit the activity of NF-κB and retrieve the imbalance of Th1/Th2 cytokine in asthma. The airway reactivity of asthma rats is decreased by roxithromycin which may be related to the reduction of IL-4 and IL-5 expression.