双氢杨梅树皮素调节巨噬细胞极化改善小鼠急性肺损伤

Ampelopsin alleviates acute lung injury in mouse by regulating macrophage polarization

目的探讨双氢杨梅树皮素(APS)对脂多糖(LPS)诱导的急性肺损伤(ALI)的保护作用,并探讨肺巨噬细胞M1/M2表型极化及其介导的炎症反应。方法将120只KM小鼠分为6组:正常对照组、模型组、双氢杨梅树皮素(100、200、400 mg/kg)组、地塞米松(DEX)处理组。除正常对照组外,其余组采用气管内滴注LPS(8 mg/kg)建立ALI模型。造模72 h后,收集肺泡灌洗液(BALF)及肺组织。肺功能测定仪测定呼吸功能[吸气阻力、每分钟最大通气量(MVV)、肺动态顺应性];HE染色观察小鼠肺组织病变情况,测定小鼠肺湿/干质量比(W/D);ELISA检测BALF中IL-6、IFN-γ的水平;流式细胞术检测F4/80+CD11b+巨噬细胞中M1型巨噬细胞标志物CD86与M2型巨噬细胞标志物CD206表达,确定巨噬细胞极化情况。结果肺功能检测结果显示,APS可降低吸气阻力(P<0.05),增大每分钟MVV(P<0.05);HE染色结果显示,APS可明显减轻ALI小鼠肺组织损伤(P<0.05);肺湿/干重比例结果显示,APS可减轻小鼠肺水肿(P<0.05);流式细胞术的检测结果显示,APS能明显减少ALI小鼠肺部F4/80+CD11b+巨噬细胞的浸润(P<0.05),并且降低了M1型巨噬细胞的比例(P<0.05)和升高M2型巨噬细胞的比例(P<0.05),抑制肺内巨噬细胞由MΦ往M1型极化,并促进M2极化;ELISA法测定BALF中细胞因子的结果显示,APS可减少肺部促炎因子IL-6和IFN-γ的表达水平(P<0.05)。结论双氢杨梅树皮素降低小鼠肺巨噬细胞比例及抑制其向M1表型的极化,促进向M2表型的极化,降低M1/M2比例,从而改善LPS诱导的ALI小鼠肺部炎症反应。

This study was designed to investigate the effect of ampelopsin on acute lung injury(ALI)induced by lipopolysaccharide(LPS),and to explore M1/M2 polarization of pulmonary macrophages and M1/M2 macrophagemediated inflammatory reaction.KM mouse were divided into 6 groups:normal control group,model group,ampelopsin groups(Doses:100,200,400 mg/kg),and dexamethasone(DEX)group.ALI models were established by intratracheal instillation of LPS(8 mg/kg).And 72 hours after,bronchoalveolar lavage fluid(BALF)and lung tissues were collected;respiratory function(inspiratory resistance,maximum ventilation per minute,and dynamic lung compliance)was measured by pulmonary function tester;the pathological changes of mouse lung tissue were observed by HE staining,and the lung coefficient and wet/dry mass ratio(W/D)of lung tissue was measured;the contents of IL-6 and IFN-γin BALF were detected by ELISA;the M1 macrophage marker CD86 and the M2 macrophage marker CD206 in F4/80+CD11b+macrophages were detected by flow cytometry.The results of lung function test showed that APS could reduce inspiratory resistance(P<0.05);HE staining showed that APS could significantly reduce lung tissue injury in ALI mice(P<0.05);the results of lung wet/dry weight ratio showed that APS could reduce lung edema in mice(P<0.05);flow cytometry showed that APS could significantly reduce the infiltration of F4/80+CD11b+macrophages in the lung of ALI mice(P<0.05),and inhibit MΦpolarizing to M1 and promote MΦpolarizing to M2(P<0.05);ELISA showed that APS could reduce the lung pro-inflammatory factors IL-6 and IFN-γ(P<0.05).In conclusion,ampelopsin could decrease the proportion of macrophages and inhibit the lung macrophage polarization to M1 phenotype,and promote the polarization to M2 phenotype,thereby alleviating the LPS-induced pulmonary inflammatory response in ALI mouse.