Abstract:
Enterohemorrhagic Escherichia coli (EHEC) is a major food-borne pathogen that causes human disease ranging from diarrhea to life-threatening complications. Accumulating evidence demonstrates that the Western diet enhances the susceptibility to enteric infection in mice, but the effect of diet on EHEC colonization and the role of human gut microbiota remains unknown. Our research aimed to investigate the effects of a Standard versus a Western diet on EHEC colonization in the human in vitro Mucosal ARtificial COLon (M-ARCOL) and the associated changes in the gut microbiota composition and activities. After donor selection using simplified fecal batch experiments, two M-ARCOL bioreactors were inoculated with a human fecal sample (n = 4) and were run in parallel, one receiving a Standard diet, the other a Western diet and infected with EHEC O157:H7 strain EDL933. EHEC colonization was dependent on the donor and diet in the luminal samples, but was maintained in the mucosal compartment without elimination, suggesting a favorable niche for the pathogen, and may act as a reservoir. The Western diet also impacted the bacterial short-chain fatty acid and bile acid profiles, with a possible link between high butyrate concentrations and prolonged EHEC colonization. The work demonstrates the application of a complex in vitro model to provide insights into diet, microbiota, and pathogen interactions in the human gut.
摘要:
肠出血性大肠杆菌(EHEC)是一种主要的食源性病原体,可引起从腹泻到危及生命的并发症的人类疾病。越来越多的证据表明,西方饮食增强小鼠对肠道感染的易感性,但是饮食对EHEC定植的影响和人类肠道微生物群的作用仍然未知。我们的研究旨在研究标准饮食与西方饮食对体外人粘膜白质结肠(M-ARCOL)中EHEC定植的影响以及肠道菌群组成和活动的相关变化。在使用简化的粪便批次实验进行供体选择后,两个M-ARCOL生物反应器接种人粪便样品(n=4),并平行运行,一个接受标准饮食的人,另一种是西方饮食,并感染了EHECO157:H7菌株EDL933。EHEC定植取决于供体和腔内样本中的饮食,但保持在粘膜区室没有消除,为病原体提供了有利的生态位,并可能充当水库。西方饮食也影响了细菌短链脂肪酸和胆汁酸谱,与高丁酸浓度和延长EHEC定殖之间可能存在联系。这项工作展示了复杂的体外模型的应用,以提供对饮食的见解,微生物群,和人体肠道中的病原体相互作用。