樱黄素抑制TLR4/MyD88通路减轻肠上皮炎症反应改善小鼠克罗恩病样结肠炎

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

目的探讨天然植物化合物樱黄素(PRU)对肠上皮细胞炎症和屏障结构的作用及其对小鼠克罗恩病样结肠炎的影响。方法建立脂多糖(LPS)诱导的结肠类器官炎症损伤模型和2,4,6-三硝基苯磺酸溶液(TNBS)诱导的小鼠结肠炎模型,用于评估PRU对肠上皮炎症反应和肠屏障的影响。另外,使用网络药理学结合体内外研究分析PRU调控肠上皮炎症影响肠炎的分子机制。结果PRU干预可抑制LPS诱导的结肠类器官中促炎介质肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)、IL-1β的释放以及改善TNBS诱导的小鼠结肠炎症状(体质量下降、疾病活动指数和炎症评分升高);同时,PRU促进LPS诱导的小鼠结肠类器官TNBS小鼠肠上皮细胞间紧密连接蛋白闭锁小带蛋白1(ZO-1),密封蛋白1(claudin-1)的表达和改善移位,同时保护肠屏障结构。PRU可靶向结合Toll样受体4(TLR4)并抑制TLR4/髓样分化因子88(MyD88)信号通路活化。结论PRU可通过靶向拮抗TLR4/MyD88信号的激活,抑制肠上皮细胞炎症和保护肠屏障损伤从而改善克罗病样肠炎。

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-1βin 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.