Xianglian Anchang Decoction Mitigates Ulcerative Colitis via Inhibition of TLR-4-Mediated Pyroptosis.

Background: Xianglian Anchang Decoction (XLAC) shows significant promise in treating ulcerative colitis (UC) based on clinical experience. However, the specific mechanism of XLAC treatment for UC is still not well understood.

Purpose: This study aims to explore the pharmacological mechanism of XLAC in treating UC through network pharmacology and experimental verification.

Methods: In this study, DSS-induced UC mouse model was established to evaluate the effects of XLAC on body weight, Disease Activity Index scores, spleen index, and colon length. Pathological change and intestinal barrier integrity were analyzed via hematoxylin-eosin, periodic acid-Schiff staining, immunofluorescence, RT-qPCR, Western blot, and ELISA. Network pharmacology and bioinformatics analyses were employed to predict potential targets of XLAC, followed by molecular docking to validate the binding affinity between key components and TLR4.

Results: XLAC significantly ameliorated weight loss, colon shortening, and splenomegaly in UC mice (P < 0.001), restored intestinal barrier integrity, and increased the expression of tight junction proteins (ZO-1/Occludin) and goblet cell numbers. Network pharmacology identified TLR4 as a key target, and molecular docking demonstrated strong binding affinity (Vina score < -5) between XLAC active components (eg, trans-4-coumaric acid, methyl cinnamate) and TLR4. In vivo experiments confirmed that XLAC downregulated the protein levels of TLR4, NLRP3, and GSDMD-N, as well as the mRNA expression of IL-1β and IL-18 (P < 0.05), thereby suppressing pyroptosis.

Conclusion: XLAC alleviates UC inflammation and intestinal barrier damage by targeting TLR4 to inhibit NLRP3 inflammasome activation and GSDMD-mediated pyroptosis. This study provides mechanistic insights into the clinical efficacy of XLAC for UC treatment.