Key Laboratory of Functional Dairy, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
School of Food and Chemical Engineering, Beijing Technology and Business University, Beijing 100048, China.
Molecules. 2019 Jan 31;24(3):513. doi: 10.3390/molecules24030513.
Exopolysaccharide (EPS) produced by probiotics may play an important role in gastrointestinal disease prevention, including ulcerative colitis. However, there is no literature reporting on the intervention effects of purified EPS. The aim of this study was to investigate the alleviating effect of the purified EPS produced by MN-BM-A01 on murine model of colitis induced by dextran sulphate sodium (DSS). A water-soluble heteropolysaccharide (EPS-1) isolated from MN-BM-A01 was composed of rhamnose, glucose, galactose, and mannose in a molar ratio of 12.9:26.0:60.9:0.25, with molecular weight of 4.23 × 10⁵ Da. After EPS-1 administration, the disease severity of mouse colitis was significantly alleviated, mainly manifesting as the decrease of disease activity index and mitigated colonic epithelial cell injury. Meanwhile, pro-inflammatory cytokines levels (tumor necrosis factor-α, interleukin-6, and interferon-γ) were significantly suppressed, the reduced expressions of tight junction protein (claudin-1, occludin, and E-canherin) were counteracted. In addition, the results in vitro showed that EPS-1 protected intestinal barrier integrity from the disruption by lipopolysaccharide in Caco-2 monolayer, increased expression of tight junction and alleviated pro-inflammatory response. Collectively, our study confirmed the protective effects of purified EPS produced by on acute colitis via alleviating intestinal inflammation and improving mucosal barrier function.
益生菌产生的胞外多糖（EPS）可能在预防胃肠道疾病方面发挥重要作用，包括溃疡性结肠炎。然而，目前尚无文献报道关于纯化 EPS 的干预效果。本研究旨在探讨 MN-BM-A01 产生的纯化 EPS 对葡聚糖硫酸钠（DSS）诱导的小鼠结肠炎模型的缓解作用。从 MN-BM-A01 中分离出的一种水溶性杂多糖（EPS-1）由鼠李糖、葡萄糖、半乳糖和甘露糖以摩尔比 12.9:26.0:60.9:0.25 组成，分子量为 4.23×105 Da。给药后，MN-BM-A01 产生的 EPS-1 可显著减轻小鼠结肠炎的严重程度，主要表现为疾病活动指数降低和结肠上皮细胞损伤减轻。同时，促炎细胞因子水平（肿瘤坏死因子-α、白细胞介素-6 和干扰素-γ）显著降低，紧密连接蛋白（Claudin-1、Occludin 和 E-cadherin）的表达减少得到缓解。此外，体外实验结果表明，EPS-1 可保护 Caco-2 单层细胞中由脂多糖引起的肠道屏障完整性的破坏，增加紧密连接的表达并减轻促炎反应。综上所述，本研究证实了 MN-BM-A01 产生的纯化 EPS 通过减轻肠道炎症和改善黏膜屏障功能对急性结肠炎具有保护作用。
