目的 探讨长梗冬青苷（pedunculoside，PE）对葡聚糖硫酸钠（dextran sulfate sodium salt，DSS）诱导溃疡性结肠炎（ulcerative colitis，UC）的治疗作用，并从体内外模型阐明其分子机制。方法 采用DSS诱导建立小鼠UC模型，联合转录组学分析，评估PE对小鼠体质量变化、结肠长度、结肠组织病理、结肠组织中促炎因子水平以及紧密连接蛋白（Occludin、E-cadherin、Claudin-1）表达的影响。采用Caco-2单层细胞模型，利用异硫氰酸荧光素-葡聚糖（FITC-葡聚糖）检测细胞通透性，评估PE对肠黏膜基础屏障功能的影响；通过Western blotting、ELISA等分子生物学实验进一步验证PE对磷脂酰肌醇3-激酶（phosphatidylinositol 3-kinase，PI3K）/蛋白激酶B（protein kinase B，Akt）信号通路、炎症因子及紧密连接蛋白表达与分布的调控作用。结果 体内实验结果显示，PE能显著降低小鼠疾病活动指数（disease activity index，DAI）评分（P＜0.001），减轻结肠组织病理损伤，降低促炎因子水平（P＜0.05、0.001），上调结肠组织中紧密连接蛋白表达（P＜0.001）；转录组测序发现PE对UC小鼠结肠组织中过度激活的PI3K/Akt信号通路具有显著的抑制作用（P＜0.001）。体外实验结果显示，PE能显著降低Caco-2单层细胞的通透性（P＜0.001），抑制DSS诱导的Caco-2细胞模型中Akt、PI3K的磷酸化（P＜0.01、0.001），降低炎症因子水平（P＜0.01、0.001），同时上调Occludin、E-cadherin、Claudin-1表达（P＜0.001）。结论 PE在体内外模型中均能通过抑制PI3K/Akt信号通路下调炎症反应并增强肠上皮屏障功能，从而发挥对DSS诱导的UC的保护作用。

Objective To investigate the therapeutic effect of pedunculoside (PE) on dextran sulfate sodium salt (DSS)-induced ulcerative colitis (UC) and elucidate its molecular mechanism through in vitro and in vivo models. Methods DSS was used to establish a mouse UC model, combined with transcriptome analysis, the effect of PE on changes in body weight, colon length, colon tissue pathology, pro-inflammatory cytokine levels in colon tissue, and expressions of tight junction proteins (Occludin, E-cadherin, Claudin-1) were evaluated. Caco-2 monolayer cell model was established, the cell permeability was detected using fluorescein isothiocyanate-glucan (FITC-glucan) to evaluate the effect of PE on intestinal mucosal barrier function. Further validation of the regulatory effect of PE on phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, inflammatory factors, and tight junction protein expression and distribution was achieved through molecular biology experiments such as Western blotting and ELISA. Results The results of in vivo experiments showed that PE could significantly reduce the disease activity index (DAI) score of mice (P < 0.001), alleviate pathological damage to colon tissue, reduce pro-inflammatory cytokine levels (P < 0.05, 0.001), and upregulate the expressions of tight junction proteins in colon tissue (P < 0.001). Transcriptome sequencing revealed that PE had a significant inhibitory effect on the overactivated PI3K/Akt signaling pathway in colon tissue of UC mice (P < 0.001). In vitro experimental results showed that PE could significantly reduce the permeability of Caco-2 monolayer cells (P < 0.001), inhibit the phosphorylation of Akt and PI3K in DSS-induced Caco-2 cell model (P < 0.01, 0.001), reduce the levels of inflammatory factors (P < 0.01, 0.001), and upregulate the expressions of Occludin, E-cadherin and Claudin-1 (P < 0.001). Conclusion PE could downregulate inflammatory response and enhance intestinal epithelial barrier function by inhibiting PI3K/Akt signaling pathway in both in vivo and in vitro models, thereby exerting a protective effect on DSS-induced UC.

R285.5

广西青年岐黄学者培育项目（GXQH202408）；广西青年科技人才托举工程（GXYESS2025031）