清肺口服液对哮喘小鼠气道炎症及肠道菌群的影响

Effects of Qinfei Oral Liquid on airway inflammation and gut microbiota in asthmatic mice

目的研究清肺口服液对哮喘小鼠气道炎症及肠道菌群的影响。方法雌性BALB/c小鼠经卵清蛋白(OVA)致敏及激发建立哮喘小鼠模型。造模成功后,清肺口服液干预组(QFL组)予清肺口服液灌胃,布地奈德吸入组(BUD组)予布地奈德混悬液雾化,粪菌移植组(FMT组)接受正常小鼠粪菌移植,OVA组及正常组予等量0.9%NaCl溶液灌胃,各组均连续治疗5d。末次治疗后4 h内,小鼠过度麻醉致死,取肺组织经HE染色评估气道炎症,取肠内容物针对16S rDNA基因V3-V4区进行测序。借助QIIME2、LEfSe以及PICRUSt2等软件分析清肺口服液干预对哮喘小鼠肠道菌群结构、丰度、多样性以及特征菌属的影响;并利用京都基因和基因组百科全书(KEGG)数据库对肠道微生物的功能进行分析预测。结果清肺口服液、布地奈德以及粪菌移植均可不同程度改善哮喘小鼠气道炎症。在门水平上,OVA组厚壁菌门(p_Firmicutes)降低,放线菌门(p_Actinobacteria)和TM7门升高,经清肺口服液治疗后丰度恢复正常。在属水平上,OVA组乳杆菌属(Lactobacillus)、普氏菌属(Prevotella)、臭杆菌属(Odoribacter)丰度下降,脱硫弧菌属(Desulfovibrio)丰度上升,经清肺口服液治疗后可改善。OVA组关键菌主要隶属于拟杆菌门的普雷沃氏菌科(f_Prevotellaceae)和厚壁菌门的梭菌科(f_Clostridiaceae);QFL组的关键菌主要隶属于变形菌门的伯克氏菌科(f_Burkholderiaceae)和巴斯德氏菌科(f_Pasteurellaceae),以及放线菌门的微球菌科(f_Micrococcaceae)。对于哮喘小鼠肠道菌群宏基因组功能预测显示:脂肪酸的生物合成,支链氨基酸降解,精氨酸以及丙酮酸代谢,丙酸代谢以及硫胺素代谢通路相关基因功能下调,硒化合物代谢通路功能上调;清肺口服液治疗后半乳糖代谢、类固醇激素生物合成以及支链氨基酸降解等通路上调,苯丙氨酸代谢通路功能下调。结论调节哮喘小鼠肠道菌群组分及其相关代谢通路,可能是清肺口服液改善哮喘小鼠气道炎症的重要机制之一。

Objective To investigate the effects of Qinfei Oral Liquid(QFL)on airway inflammation and gut microbiota in asthmatic mice.Methods Female BALB/c mice were sensitized and challenged with ovalbumin(OVA)to establish a murine model of asthma.After successful modeling,QFL group was given QFL by gavage,the budesonide(BUD)group given budesonide suspension by nebulization,fecal microbiota transplantation(FMT)group received fecal bacteria transplantation from normal mice,OVA group and normal group given equal volume saline by gavage,and all the groups were treated for 5 consecutive days.Within 4 h after the last treatment,mice were sacrifice by excessive anesthesia,and lung tissues were harvested for HE staining to assess airway inflammation;Intestinal contents were taken for sequencing of the V3-V4 region of the 16S rDNA gene.Software such as QIIME2,LEfSe and PICRUSt 2 were used to analyze the effects of QFL intervention on the structure,abundance,diversity,and characteristics of intestinal flora in asthmatic mice,and the KEGG database was used to analyze and predict the functions of intestinal microbes.Results The administration of QFL,budesonide and fecal microbiota transplantation all ameliorated airway inflammation in asthmatic mice to varying degrees.At the phylum level,the p_Firmicutes was decreased,while the p_Actinobacteria and TM7 were increased in the OVA group,and the abundance was restored to normal after treatment with QFL.At the genus level,the abundances of Lactobacillus,Prevotella,Odoribacter decreased and Desulfovibrio increased in the ova group,which could be improved after treatment with QFL.OVA group heterogeneity bacteria are mainly affiliated with f_Prevotellaceae of the p_Bacteroidetes and f_Clostridiaceae of the p_Firmicutes;Key bacteria in the QFL group were mainly affiliated with f_Burkholderiaceae and f_Pasteurellaceae of the p_Proteobacteria,and f_Micrococcaceae of the p_Actinobacteria.The gut flora metagenomic functional prediction of asthmatic mice showed that:biosynthesis of fatty acids,branched chain amino acid degradation,arginine and pyruvate metabolism as well as pyruvate metabolism and thiamine metabolism pathway related gene functions were down-regulated,while selenium compound metabolism pathway functions were up-regulated;Pathways such as galactose metabolism,steroid hormone biosynthesis and branched chain amino acid degradation were up-regulated after treatment with QFL,while the function of phenylalanine metabolic pathway was down-regulated.Conclusion The modulation of intestinal flora composition and its related metabolic pathways in asthmatic mice may be one of the important mechanisms by which QFL ameliorates airway inflammation in asthmatic mice.