黄芪多糖治疗和预防性给药对感染PR8小鼠的保护作用及机制研究

Protective effect of therapeutic and prophylactic administration of Astragalus polysaccharides on influenza virus PR8-induced acute lung injury model

目的:研究黄芪多糖不同给药方式对流感病毒PR8小鼠急性肺损伤的保护作用。方法:实验分为正常对照组、PR8组、治疗给药组、预防给药组、利巴韦林对照组。用甲型流感病毒鼠肺适应株A/PR/8/4制备小鼠流感病毒性肺炎模型,黄芪多糖用不同给药方式干预后,观察小鼠肺指数和肺病理改变,用比色法检测血液和肺组织丙二醛(MDA)水平,超氧化物酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性,qPCR检测肺组织TNF-α、IL-6、IL-1β、IFN-α mRNA含量,Western blot检测肺组织凋亡相关蛋白Caspase-3、8、9表达。结果:黄芪多糖治疗和预防给药均能降低肺指数,减轻肺损伤;下调肺组织MDA水平及上调SOD、GSH-Px活性(P<0.05);抑制TNF-α、IFN-α、IL-6、IL-1β的分泌(P<0.05);减少Caspase-3、8、9表达(P<0.05)。结论:黄芪多糖通过降低炎性细胞因子分泌和抑制组织细胞凋亡,缓解甲型流感病毒PR8所致的急性肺损伤。

Objective: To investigate the effect of Astragalus polysaccharides(APS) treatment on influenza virus PR8-induced lung injury and explore its protective effect and mechanism. Methods: The mice were divided into control group,treatment group,prevention group and ribavirin control group.The acute lung injury mode was established by infection of influenza virus strain A/PR/8/4(H1N1),and treated with different administration of APS by intragastric administration.After treatment with APS,pulmonary index and pathological changes of lung tissue were observed.The contents of MDA,GSH-Px and SOD in blood and lung tissues was detected by colorimetric method.The expression of inflammatory cytokines TNF-α,IL-6,IL-1β,IFN-α and Caspase-3,8,9 in lung tissue were detected respectively by qPCR and Western blot. Results: APS treatment group and prevention group could reduce the lung index and the lung tissue lesions,down-regulate the level of MDA,TNF-α,IFN-α,IL-6,IL-1β and increase enzyme activity of SOD,GSH-Px( P <0.05).The expression of Caspase-3,8,9 were significant decreased in treatment group and prevention group compared with PR8 group( P <0.05). Conclusion: The different administration of APS can relieve pathological damage of pneumonia induced by influenza virus PR8 through reducing the levels of inflammatory cytokines and inhibiting cell apoptosis.