BackgroundAntrodia cinnamomea compound decoction (ACCD), a Chinese herbal extract composed of Antrodia cinnamomea, Rhinacanthus nasutus (L.) Kurz and Phellinus igniarius (L. ex Fr.), were widely used with anti-inflammatory activity. However, the effects and mechanisms of ACCD on the lung inflammation induced by PM2.5 are not fully understood. This study aims to reveal the effect of ACCD on PM2.5-induced lung inflammation and analyze the possible mechanisms through gene chip expression profiling. MethodsMale Wistar rats were subjected to lung damage by stimulation with 10% PM2.5, with/without ACCD (0.67g/kg/d) intervention. The HE, AB-PAS staining and IL-1β were performed to evaluate the effect of ACCD in the treatment of lung inflammation caused by PM2.5. In addition, the extracted lung genes were detected based on the gene chip expression profile. Bioinformatics analysis and quantitative real-time polymerase chain reaction assay (Q-PCR) were used to analysis and verify the related differentially expressed genes (DEGs). ResultsResults showed that instillation of PM2.5 increased the inflammatory cells immersion in the airways and the acid mucus content in the tracheal epithelium compared with the sham group, and it increased the IL-1β levels in Bronchoalveolar lavage fluid (BALF). ACCD reduced inflammatory cell immersion in airways, alleviated goblet cell metaplasia in tracheal epithelium and reduced IL-1β levels in BALF. A total of 99 genes with significant differential expression were identified (p < 0.05) after ACCD treatment compared with the model group, including 48 up-regulated and 51 down-regulated genes. Bioinformatics analysis showed that these DEGs were mainly related to inflammatory response and significantly enriched in cancer signaling pathway. Five of the DEGs were subjected to Q-PCR and three of them (Plcβ-1, Axin2, Ccbe1) were significant difference (p < 0.05). ConclusionOur study suggests that ACCD may exert anti-inflammatory effects on PM2.5-induced lung inflammation via the cancer pathway, and that Plcβ-1, Axin2, and Ccbe1 may be key targets of ACCD action on PM2.5-induced lung inflammation. This work could provide genomic clues for the continued study of ACCD for the therapy of PM2.5-induced lung inflammation.