[Prunetin inhibits TLR4/MyD88 pathway to attenuate intestinal epithelial inflammatory response and ameliorate mouse Crohn's disease-like colitis].

Objective To investigate the regulatory role of natural plant compound prunetin (PRU) on the intestinal epithelial inflammation and the barrier structure in Crohn's disease-like colitis. Methods A lipopolysaccharide (LPS)-induced inflammatory injury model of colonic organoids and a 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced mouse colitis model were established to evaluate the effects of PRU on the intestinal epithelial inflammation and intestinal barrier. In addition, network pharmacological predictions, combined with in vitro and in vivo studies, were used to analyze the molecular mechanisms by which PRU modulates intestinal epithelial inflammation and intestinal barrier in CD-like colitis. Results PRU inhibited the release of pro-inflammatory factors such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β in LPS-induced colonic organoids, and ameliorated the colitis symptoms in TNBS-induced mice, including body mass loss, elevated disease activity index and increased inflammation scores. Meanwhile, PRU promoted the expression of tight junction proteins (ZO-1 and claudin-1) and improved their translocation restoration in LPS-induced colonic organoids and TNBS-induced intestinal epithelial cells, while maintaining the intestinal barrier structure. Mechanistically, PRU targeted the Toll-like receptor 4 (TLR4) and inhibited the activation of the TLR4/myeloid differentiation primary response gene 88 (MyD88) signaling pathway. Conclusion PRU can antagonize TLR4/MyD88 signaling, thereby inhibiting intestinal epithelial inflammation and protecting against intestinal barrier damage, which helps ameliorate Crohn's disease-like colitis.