Abstract：
Shigella flexneri is a prevalent foodborne and waterborne pathogen that threatens human health. Our previous research indicated that the Lactiplantibacillus plantarum Y12 exopolysaccharide (L-EPS) potentially inhibited the pathogenicity of S. flexneri. The in vitro results of this study demonstrated that L-EPS effectively mitigated the symptoms induced by S. flexneri in HT-29 cells, including inhibited gene expression levels of IL-1β, IL-6, IL-8, TNF-α, TLR 2/4, and NOD1/2; decreased apoptosis ratio; and alleviated damage degree of intestinal barrier function (Zona occludens 1, Occludin, and Claudin-1). The in vivo results demonstrated that S. flexneri treated with L-EPS elicited mild adverse physiological manifestations, an inflammatory response, and tissue damage. The infection of S. flexneri caused significant alterations in the abundance of phylum (Firmicutes, Bacteroidota, Actinobacteriota, and Proteobacteria), family (Lachnospiraceae, Muribaculaceae, Rikenellaceae, Prevotellaceaea, Ruminococcaceae, and Lactobaillaceae), and genus (Escherichia Shigella and Lachnospirillaceae NK4A136 group) within the cecal microbiota. These changes were accompanied by perturbations in taurine and hypotaurine metabolism, tricarboxylic acid (TCA) cycle activity, arginine biosynthesis, and histidine metabolic pathways. However, intervention with L-EPS attenuated the dysbiosis of cecal microbiota and metabolic disturbances. In summary, our research suggested a potential application of L-EPS as a functional food additive for mitigating S. flexneri infection.
摘要：
福氏志贺氏菌是一种威胁人类健康的食源性和水性致病菌。我们先前的研究表明，植物乳杆菌Y12胞外多糖（L-EPS）可能抑制福氏链球菌的致病性。本研究的体外结果表明，L-EPS有效缓解了弗氏链球菌在HT-29细胞中诱导的症状，包括抑制IL-1β的基因表达水平，IL-6，IL-8，TNF-α，TLR2/4和NOD1/2；降低细胞凋亡率；并减轻肠屏障功能的损伤程度（Zonaoccluddens1，Occludin，和Claudin-1）。体内结果表明，用L-EPS治疗的福氏链球菌引起轻度不良生理表现，炎症反应,和组织损伤。福氏杆菌的感染导致门的丰度发生重大变化(Firmicutes，拟杆菌,放线菌,和变形杆菌），科（天花科，Muribaculaceae,Rikenellaceae，Prevotellacea，Ruminocycaceae,和乳糖科），盲肠微生物群中的和属（大肠杆菌志贺氏菌和LachnospirillaceaeNK4A136组）。这些变化伴随着牛磺酸和亚牛磺酸代谢的扰动，三羧酸（TCA）循环活性，精氨酸生物合成，和组氨酸代谢途径。然而,L-EPS的干预减轻了盲肠微生物群的菌群失调和代谢紊乱。总之,我们的研究表明,L-EPS作为一种功能性食品添加剂在缓解福氏链球菌感染方面具有潜在的应用价值.
