淫羊藿苷干预支气管哮喘小鼠自噬的机制研究

A study on mechanism of icariin in intervention of autophagy in mice with bronchial asthma

中文关键词: 支气管哮喘  淫羊藿苷  自噬  MAPK/Erk1/2/mTOR信号通路

英文关键词: bronchial asthma  icariin  autophagy  MAPK/Erk1/2/mTOR signaling pathway

中文摘要:

      目的 观察淫羊藿苷(Icariin)对哮喘小鼠自噬和MAPK/Erk1/2/mTOR通路的作用.方法 40只SPF级小鼠分为空白组(A组)、哮喘模型组(B组)、淫羊藿苷低(C组)、高(D组)浓度组.肺功能仪检测小鼠的气道阻力(RL)、肺动态顺应性(Cdyn);ELISA法检测小鼠血清中炎症因子IL-6、TNF-α;HE染色法观察小鼠肺组织病理变化;透射电镜观察支气管上皮细胞超微结构;Western blot检测肺组织自噬相关及信号通路蛋白的表达.结果 哮喘模型组小鼠气道顺应性降低,气道阻力增加(P＜0.01);血清IL-6、TNF-α水平升高(P＜0.05);气道管壁增厚、炎症细胞浸润增加;肺组织上皮细胞自噬小体累积,细胞核皱缩;LC3 Ⅱ、Beclin-1表达增加,P62下降(P＜0.001);p-mTOR、p-p38 MAPK、p-ERK1/2表达水平下降(P＜0.01);淫羊藿苷干预后的哮喘小鼠气道高反应下降(P＜0.05),血清炎症因子减少(P＜0.05);气道炎症细胞浸润减少,自噬小体数量减少,LC3 Ⅱ、Beclin-1表达下降(P＜0.001),P62及p-mTOR、p-p38 MAPK、p-ERK1/2增加(P＜0.001).结论 淫羊藿苷可以改善哮喘小鼠气道高反应和炎症状态,抑制哮喘引起的小鼠肺组织上皮细胞自噬.

英文摘要:

      Objective To observe the effects of icariin on autophagy and the MAPK/Erk1/2/mTOR pathway in asth-matic mice.Methods 40 SPF-grade mice were divided into blank control group(group A),asthma model group(group B),low-dose icariin intervention group(group C)and high-dose icariin intervention group(group D).Pulmonary function instru-ment was used to detect airway resistance(RL)and dynamic lung compliance(Cdyn)of mice.ELISA was employed to meas-ure the levels of inflammatory cytokines(IL-6 and TNF-α).Pathological changes in lung tissue were observed via HE stai-ning.Transmission electron microscope was used to observe the ultrastructure of bronchial epithelial cells.Western blot was used to determine the expression of autophagy-related proteins and signaling pathway proteins in lung tissue.Results In the asthma model group,the Cdyn decreased and RL increased(P＜0.01);the levels of serum IL-6 and TNF-α increased(P＜0.05);the airway wall thickened and the infiltration of inflammatory cells increased;autophagosomes accumulated in the epi-thelial cells of lung tissue,and the nuclei shrunken;the expression levels of LC3 Ⅱ and Beclin-1 increased,while P62 de-creased(P＜0.001);the expression levels of p-mTOR,p-P38 MAPK and p-ERK1/2 decreased(P＜0.01).After interven-tion with icariin,airway hyperresponsiveness decreased(P＜0.05)and serum inflammatory cytokines decreased(P＜0.05)in asthmatic mice;the infiltration of airway inflammatory cells decreased,the number of autophagosomes decreased;the expres-sion levels of LC3 Ⅱ and Beclin-1 decreased(P＜0.001),and P62,p-mTOR,p-p38 MAPK,and p-ERK1/2 increased(P＜0.001).Conclusion Icariin can improve airway hyperresponsiveness and inflammation in asthmatic mice,and inhibit the au-tophagy of lung epithelial cells induced by asthma.