ObjectiveTo investigate the mechanism by which Shengjiang Pingchuan Zhike pills （SPZP） alleviate airway injury in the rat model of cough variant asthma （CVA） via regulating autophagy through activating the adenosine monophosphate-activated protein kinase （AMPK）/mammalian target of rapamycin （mTOR）/Unc-51-like autophagy activating kinase 1 （ULK1） signaling pathway based on transcriptomics， thus providing experimental evidence for the clinical application of SPZP. MethodsForty SPF-grade SD rats were enrolled in the present study and randomly via the random number table method assigned into four groups： a blank group， a model group， a SPZP （2 160 mg·kg^-1·d^-1） group， and a positive drug （montelukast sodium， MTL， 0.9 mg·kg^-1·d^-1）group， with 10 rats in each group. After one week of adaptive feeding， the rat model of cough variant asthma （CVA） was established by two-week sensitization with ovalbumin （OVA） and aluminium hydroxide， followed by capsaicin atomization challenge. Rats in the blank group received an equal volume of normal saline during modeling. Upon successful modeling， rats in the SPZP group and positive drug group were administrated with SPZP suspension and MTL solution， respectively， while those in the blank and model groups received the same dose of normal saline by gavage. The whole intervention lasted for 21 consecutive days. After the intervention， general behaviors of rats in each group were observed. Pulmonary function indicators were subsequently detected. Hematoxylin-eosin （HE） staining was performed to visualize the pathological morphology of the lung tissue， and periodic acid-Schiff （PAS） staining was adopted to evaluate airway mucus secretion. Transcriptomic sequencing was conducted to screen differentially expressed genes in the lung tissue across groups. The levels of inflammatory cytokines including interleukin （IL）-4， IL-5， immunoglobulin E （IgE）， and interferon-γ （IFN-γ） in the bronchoalveolar lavage fluid （BALF） were quantified by enzyme-linked immunosorbent assay （ELISA）. Immunofluorescence staining was used for detecting the co-localization of autophagy-related protein Beclin-1 and phosphorylated mammalian target of rapamycin （p-mTOR）. Transmission electron microscopy was employed to count autophagosomes and observe mitochondrial morphological changes in the lung tissue. Western blot assay was utilized to measure the expression levels of AMPK/mTOR/ULK1 axis-related proteins， including AMPK， phosphorylated adenosine monophosphate-activated protein kinase （p-AMPK）， mTOR， phosphorylated mammalian target of rapamycin （p-mTOR）， ULK1， and phosphorylated Unc-51-like autophagy activating kinase 1 （p-ULK1） as well as the autophagy biomarkers Beclin-1 and selective autophagy adaptor protein p62 in lung specimens. ResultsCompared with the blank group， the model group exhibited markedly elevated cough frequency accompanied by wheezing and stridor， dull fur， poor mental activity， diminished motor activity， accelerated respiratory rate， and weakened sensory response and mobility to external stimuli， accompanied by a declining tendency of body mass. Meanwhile， the model group exhibited decreased dynamic lung compliance， increased airway resistance （P<0.01）， severe pathological damage and excessive mucus secretion in the lung tissue （P<0.01）， and elevated levels of IL-4， IL-5， and IgE and declined level of IFN-γ in the BALF （P<0.01）. Ultrastructural observation revealed damaged mitochondrial morphology and a sharp reduction in the number of autophagosomes in the lung tissue. In addition， the expression of p-AMPK， p-ULK1， and Beclin-1 were downregulated， whereas p-mTOR and p62 were highly expressed （P<0.05， P<0.01） in the model group. Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） enrichment analyses demonstrated significant enrichment of AMPK， mTOR， and autophagy-related pathways. Compared with the model group， both the positive drug group and SPZP group obtained visible improvements in general behavioral manifestations and obvious recovery of pulmonary function indicators （P<0.05）， alleviated pulmonary pathological lesions and suppressed excessive airway mucus secretion （P<0.05）， recovered levels of inflammatory cytokines in the BALF （P<0.05）， restored mitochondrial morphology， increased autophagosomes， upregulated expression levels of p-AMPK， p-ULK1， and Beclin-1， and downregulated expression levels of p-mTOR and p62 （P<0.05）. ConclusionSPZP can effectively ameliorate airway inflammation and improve the pulmonary function in the rat model of CVA by activating the AMPK/mTOR/ULK1 signaling pathway， enhancing autophagy in the lung tissue， and inhibiting excessive airway mucus secretion and immune inflammatory imbalance.