Abstract：
Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disorder characterized by visceral pain and gut dysmotility. However, the specific mechanisms by which Lactobacillus strains relieve IBS remain unclear. Here, we screened Lactobacillus strains from traditional Chinese fermented foods with potential IBS-alleviating properties through in vitro and in vivo experiments. We demonstrated that Lactiplantibacillus plantarum D266 (Lp D266) administration effectively modulates intestinal peristalsis, enteric neurons, visceral hypersensitivity, colonic inflammation, gut barrier function, and mast cell activation. Additionally, Lp D266 shapes gut microbiota and enhances tryptophan (Trp) metabolism, thus activating the aryl hydrocarbon receptor (AhR) and subsequently enhancing IL-22 production to maintain gut homeostasis. Mechanistically, Lp D266 potentially modulates colonic physiology and enteric neurons by microbial tryptophan metabolites. Further, our study indicates that combining Lp D266 with Trp synergistically ameliorates IBS symptoms. Together, our experiments identify the therapeutic efficacy of tryptophan-catabolizing Lp D266 in regulating gut physiology and enteric neurons, providing new insights into the development of probiotic-mediated nutritional intervention for IBS management.
摘要：
肠易激综合征（IBS）是一种常见的功能性胃肠病，其特征是内脏疼痛和肠道运动障碍。然而,乳杆菌菌株缓解IBS的具体机制尚不清楚.这里,通过体外和体内实验，我们从中国传统发酵食品中筛选出具有潜在IBS缓解特性的乳酸菌菌株。我们证明了植物乳杆菌D266（LpD266）的给药有效地调节肠蠕动，肠神经元，内脏过敏，结肠炎症,肠屏障功能,和肥大细胞激活。此外,LpD266塑造肠道菌群并增强色氨酸（Trp）代谢，从而激活芳香烃受体（AhR）并随后增强IL-22的产生以维持肠道稳态。机械上,LpD266可能通过微生物色氨酸代谢产物调节结肠生理学和肠神经元。Further,我们的研究表明，LpD266与Trp联合使用可协同改善IBS症状。一起,我们的实验确定了色氨酸分解代谢LpD266在调节肠道生理和肠神经元中的治疗功效，为益生菌介导的IBS管理营养干预的发展提供新的见解。
