五味子乙素对过敏性哮喘小鼠IL-4/IL-13/STAT6通路及气道杯状细胞凋亡的影响

Effects of schisandrin B on IL-4/IL-13/STAT6 pathway and apoptosis of airway goblet cells in allergic asthma mice

目的:探究五味子乙素对过敏性哮喘小鼠的治疗作用及对IL-4/IL-13/STAT6信号通路的影响。方法:BALB/c小鼠随机分为6组:空白对照组、模型组、五味子乙素低(20 mg/kg)、中(30 mg/kg)、高(40 mg/kg)剂量组和地塞米松组(2 mg/kg),每组12只。除空白对照组外,其他各组均构建过敏性哮喘小鼠模型,造模同时分别灌胃给予相应药物。末次OVA激发24 h后,ELISA检测支气管肺泡灌洗液(BALF)中炎症因子IL-4、IL-13、IFN-γ水平。取出肺脏,计算肺/体质量指数。HE染色检测小鼠肺组织形态学变化,并进行炎症反应评分。TUNEL和PAS染色结合检测小鼠肺组织杯状细胞凋亡率;Western blot检测小鼠肺组织IL-4、IL-13、p-STAT6蛋白表达。结果:与空白对照组相比,模型组小鼠肺组织结构损伤严重,有大量炎症细胞浸润,肺/体质量指数、炎症反应评分、气道杯状细胞凋亡率、BALF中IL-4、IL-13水平及肺组织中IL-4、IL-13、p-STAT6蛋白表达显著升高(P<0.05),IFN-γ水平显著降低(P<0.05);与模型组相比,五味子乙素各剂量组和地塞米松组肺组织结构较完整,病变程度减轻,肺/体质量指数、炎症反应评分、气道杯状细胞凋亡率、BALF中IL-4、IL-13水平及肺组织中IL-4、IL-13、p-STAT6蛋白表达显著降低(P<0.05),IFN-γ水平显著升高(P<0.05),且呈剂量依赖关系。五味子乙素高剂量组和地塞米松组小鼠肺/体质量指数、炎症因子水平(IL-4、IL-13、IFN-γ)、细胞凋亡率及IL-4、IL-13、p-STAT6蛋白表达差异均无统计学意义(P>0.05)。结论:五味子乙素可能通过抑制IL-4/IL-13/STAT6信号通路减轻过敏性哮喘小鼠炎症反应,缓解肺组织病理损伤。

Objective:To explore therapeutic effect of schisandrin B on allergic asthma mice and its effect on IL-4/IL-13/STAT6 signaling pathway.Methods:BALB/c mice were randomly divided into six groups:blank control group,model group,schisandrin B low(20 mg/kg),medium(30 mg/kg),high(40 mg/kg)dose groups and dexamethasone group(2 mg/kg),with 12 mice in each group.In addition to blank control group,the other groups were established allergic asthma mouse model,and given corresponding drugs for intragastric intervention at the same time.24 h after the last OVA exciting,levels of IL-4,IL-13,IFN-γin bronchoalveolar lavage fluid(BALF)were detected by ELISA.Lungs were removed and lung/body mass index was calculated.HE staining was used to detect morphological changes of lung tissue in mice,and inflammatory response was scored.Apoptosis rate of goblet cells was detected by TUNEL and PAS staining,and protein expressions of IL-4,IL-13 and p-STAT6 were detected by Western blot.Results:Compared with blank control group,lung tissue structure was seriously damaged in model group,and number of inflammatory cells infiltration was observed,lung/body mass index,inflammatory response score,apoptosis rate of goblet cells,levels of IL-4 and IL-13 in BALF,and protein expressions of IL-4,IL-13 and p-STAT6 in lung tissue were significantly increased(P<0.05),level of IFN-γwas decreased(P<0.05);compared with model group,lung tissue structures were more complete in schisandrin B groups and dexamethasone group,and degree of pathological changes was reduced,lung/body mass index,inflammatory response score,apoptosis rate of goblet cells,levels of IL-4 and IL-13 in BALF,and protein expressions of IL-4,IL-13 and p-STAT6 in lung tissue were decreased(P<0.05),level of IFN-γwas significantly increased(P<0.05),which was in dose-dependent manner.There was no statistically significant difference in indicators between high-dose schisandrin B group and dexamethasone group(P>0.05),including lung/body mass index,cytokine levels(IL-4,IL-13,IFN-γ),cell apoptosis rate and protein expressions of IL-4,IL-13 and p-STAT6.Conclusion:Schisandrin B may reduce inflammatory reaction and lung tissue pathological damage in allergic asthma mice by inhibiting IL-4/IL-13/STAT6 signaling pathway.