ObjectiveTo explore the possible mechanism of reducing cholecystitis and preventing cholelithiasis by Dahuang Lingxian Formula(大黄灵仙方, DLF). MethodsFifty SD rats were randomly divided into blank group, model group, DLF group, DLF + blank inhibitor group, and DLF + inhibitor group, with 10 rats in each group. The rat model of cholecystitis was established by lipopolysaccharide (LPS) induction in all the groups except for the blank group. Rats in DLF group, DLF + blank inhibitor group and DLF + inhibitor group received intragastric administration of 320 mg/ (kg·d) of DLF 3 days before the preparation of cholecystitis model, while those in blank group and model group were given 2 ml/100 g of distilled water by gastric, twice a day, for 6 consecutive days. Hematoxylin-eosin (HE) staining was used to observe the histopathologic changes of bile duct tissues in each group. The expression of nuclear factor κB (NF-κB) protein in bile duct tissues was detected by immunohistochemistry. The expression levels of interleukin1β (IL-1β) and tumor necrosis factor α (TNF-α) in serum of rats were detected by enzym-linked immunosorbent assay (ELISA). The mRNA expression levels of miRNA-30b, transforming growth factor β1 (TGF-β1), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) and bone morphogenetic protein 2 (BMP2) in bile duct tissues were detected by real-time PCR, and the protein expression levels of TGF-β1, NLRP3 and BMP2 were detected by Western blot. ResultsCompared to those in the blank group, the structure of the bile duct in the model group was abnormal, and a large number of lymphocytes, plasma cell infiltration and bile canaliculi dilation were seen in the portal area; the positive expression of NF-κB protein increased; there was nuclear infiltration; the expressions of serum inflammatory factors IL-1β and TNF-α, as well as the mRNA and protein expressions of TGF-β1, NLRP3 and BMP2 in bile duct tissue significantly increased, while the expression level of miRNA-30b significantly decreased (P<0.01). Compared to those in the model group, the pathological morphology of the bile ducts in the DLF group and DLF + blank inhibitor group was improved, and the infiltration of inflammatory cells was reduced, with decreased positive expression of NF-κB and nuclear infiltration; expression levels of serum inflammatory factors IL-1β and TNF-α, and the mRNA and protein expressions of TGF-β1, NLRP3 and BMP2 in bile duct tissue decreased, while the expression level of miRNA-30b significantly increased (P<0.05 or P<0.01). Compared to the model group, those indicators in the DLF + inhibitor group was not significantly improved (P>0.05). There was no significant difference in the indicators between the DLF group and the DLF + blank inhibitor group (P>0.05). ConclusionDLF may play a role in delaying the progression of cholelithiasis by regulating the expression of miRNA-30b and inflammation-fibrosis related factors.