OBJECTIVE: To investigate the efficacy of active compounds of Chanqin (CQ) granules on PM2.5-induced airway neurogenic inflammation in vivo,and to elucidate the underlying mechanisms of action.METHODS: The Traditional Chinese Medicine systems pharmacology (TCMSP) database was searched,and the results were combined with oral bioavailability and drug analysis to identify the compounds in CQ granules.The pharmacophore modeling approach was used to predict the compound targets,and the diseases corresponding to the targets were obtained by searching the therapeutic target database (TTD),pharmacogenomics knowledgebase (PharmGKB) and DrugBank databases.Cytoscape software was used to construct the network pharmacological charts for Component-Target and Target-Disease interactions of the CQ granules.Then,the mechanisms of action and effectiveness of CQ granules for the treatment of PM2.5-induced airway neurogenic inflammation were analyzed.RESULTS: A total of 195 compounds and 171 targets were obtained from the analyses.A total of 569 corresponding diseases were identified for these targets.Component-target and target-disease networks were constructed.The possible mechanisms and effective components in CQ granules for treating airway neurogenic inflammation were analyzed.Quercetin,kaempferol and isorhamnetin,beta-sitosterol and sitosterol,which are typically found in the formulation,have extensive pharmacological activities,including anti-inflammatory,antioxidant and antiviral actions and neuroprotective properties.Among these targets,androgen receptor,estrogen receptor,prostaglandin G/H synthase 2,and inducible nitric oxide synthase play important pathological roles,including the induction of neurogenic inflammation.CQ granules may have therapeutic effectiveness for numerous diseases in addition to respiratory diseases,including neoplasms,digestive system diseases,cardiovascular diseases,respiratory tract diseases and nervous system diseases.In vivo,CQ granules are effective in treating pulmonary inflammation and downregulate neuropeptides in the bronchoalveolar lavage fluid after PM2.5 exposure.CQ granules significantly decreased the levels of neurokinin A,neurokinin B and calcitonin gene-related peptide in the lung and dorsal root ganglia.CQ also significantly suppressed the upregulation of p-extracellular regulated protein kinase 1/2 and p-methyl ethyl ketone 1/2 induced by PM2.5 exposure.CONCLUSION: CQ granules have potential for the treatment of neurogenic inflammation induced by PM2.5 in vivo,and the mechanism might involve downregulation of neuropeptides in the BALF,lung and dorsal root ganglia.