Abstract：
Probiotics are host-friendly microorganisms that can have important health benefits in the human gut microbiota as dietary supplements. Maintaining a healthy gut microbial balance relies on the intricate interplay among the intestinal microbiota, metabolic activities, and the host\'s immune response. This study aims to explore if a mixture of Heyndrickxia coagulans [ATB-BCS-042] and Lacticaseibacillus casei [THT-030-401] promotes in vitro this balance in representative gut microbiota from healthy individuals using the Triple-SHIME® (Simulation of the Human Intestinal Microbial Ecosystem). Metataxonomic analysis of the intestinal microbes revealed that the probiotic mix was not causing important disruptions in the biodiversity or microbial composition of the three simulated microbiota. However, some targeted populations analyzed by qPCR were found to be disrupted at the end of the probiotic treatment or after one week of washout. Populations such as Cluster IV, Cluster XVIa, and Roseburia spp., were increased indicating a potential gut health-promoting butyrogenic effect of the probiotic supplementation. In two of the systems, bifidogenic effects were observed, while in the third, the treatment caused a decrease in bifidobacteria. For the health-detrimental biomarker Escherichia-Shigella, a mild decrease in all systems was observed in the proximal colon sections, but these genera were highly increased in the distal colon sections. By the end of the washout, Bacteroides-Prevotella was found consistently boosted, which could have inflammatory consequences in the intestinal context. Although the probiotics had minimal influence on most quantified metabolites, ammonia consistently decreased after one week of daily probiotic supplementation. In reporter gene assays, aryl hydrocarbon receptor (AhR) activation was favored by the metabolic output obtained from post-treatment periods. Exposure of a human intestinal cell model to fermentation supernatant obtained after probiotic supplementation induced a trend to decrease the mRNA expression of immunomodulatory cytokines (IL-6, IL-8). Overall, with some exceptions, a positive impact of H. coagulans and L. casei probiotic mix was observed in the three parallel experiments, despite inter-individual differences. This study might serve as an in vitro pipeline for the impact assessment of probiotic combinations on the human gut microbiota.
摘要：
益生菌是宿主友好的微生物，可以在人类肠道微生物群中作为膳食补充剂具有重要的健康益处。保持健康的肠道微生物平衡依赖于肠道微生物群之间复杂的相互作用。代谢活动，和宿主的免疫反应。本研究旨在探讨Heyndrickxia凝结菌[ATB-BCS-042]和干酪乳杆菌[THT-030-401]的混合物是否使用Triple-SHIME®（人体肠道微生物系统的模拟）在体外促进健康个体代表性肠道微生物群中的这种平衡。肠道微生物的代谢分析显示，益生菌混合物并未对三种模拟微生物群的生物多样性或微生物组成造成重大破坏。然而,通过qPCR分析的一些靶向群体在益生菌治疗结束时或在冲洗一周后被破坏.群体，如第四组，群集XVIa，和Roseburiaspp.,增加，表明益生菌补充剂具有潜在的促进肠道健康的产丁作用。在两个系统中，观察到双歧作用，而在第三，该治疗导致双歧杆菌减少。对于有害健康的生物标志物埃希氏菌志贺氏菌，在近端结肠切片中观察到所有系统的轻度减少，但是这些属在远端结肠切片中高度增加。冲洗结束时，拟杆菌-普雷沃菌被发现持续增强，这可能在肠道环境中产生炎症后果。尽管益生菌对大多数定量代谢物的影响很小，每天补充益生菌一周后，氨持续下降。在报告基因测定中，从治疗后阶段获得的代谢输出有利于芳香烃受体（AhR）激活。将人肠细胞模型暴露于益生菌补充后获得的发酵上清液诱导了降低免疫调节细胞因子（IL-6，IL-8）mRNA表达的趋势。总的来说,除了一些例外,在三个平行实验中观察到了凝结芽孢杆菌和干酪乳杆菌益生菌混合物的积极影响，尽管个体之间存在差异。这项研究可能作为益生菌组合对人体肠道微生物群影响评估的体外管道。
