Deprivation of dietary fiber in specific-pathogen-free mice promotes susceptibility to the intestinal mucosal pathogen Citrobacter rodentium

Abstract

The change of dietary habits in Western societies, including reduced consumption of fiber, is linked to alterations in gut microbial ecology. Nevertheless, mechanistic connections between diet-induced microbiota changes that affect colonization resistance and enteric pathogen susceptibility are still emerging. We sought to investigate how a diet devoid of soluble plant fibers impacts the structure and function of a conventional gut microbiota in specific-pathogen-free (SPF) mice and how such changes alter susceptibility to a rodent enteric pathogen. We show that absence of dietary fiber intake leads to shifts in the abundances of specific taxa, microbiome-mediated erosion of the colonic mucus barrier, a reduction of intestinal barrier-promoting short-chain fatty acids, and increases in markers of mucosal barrier integrity disruption. Importantly, our results highlight that these low-fiber diet-induced changes in the gut microbial ecology collectively contribute to a lethal colitis by the mucosal pathogen Citrobacter rodentium , which is used as a mouse model for enteropathogenic and enterohemorrhagic Escherichia coli (EPEC and EHEC, respectively). Our study indicates that modern, low-fiber Western-style diets might make individuals more prone to infection by enteric pathogens via the disruption of mucosal barrier integrity by diet-driven changes in the gut microbiota, illustrating possible implications for EPEC and EHEC infections.

Akkermansia muciniphila regulates food allergy in a diet-dependent manner

“…In line with previous ndings 14,15,17 , the FF-fed mice exhibited a two-fold reduction in the colonic mucus layer thickness (Fig. 1b-d, Extended Data Fig.…”

“…Diet is an important environmental factor that affects the mucus barrier through the microbiota because: 1) dietary ber deprivation increases deterioration of the colonic mucus layer by mucolytic gut bacteria 14,15 ; and 2) Western-style diet increases the permeability of the colonic mucus layer 16 . The ber-deprived microbiota-mediated mucus barrier dysfunction re ects in enhanced susceptibility to infection by Citrobacter rodentium, a pathogen that must cross the mucus layer to reach the gut epithelium and initiate mucosal infection 14,17 . Nevertheless, little is known about how the diet-mediated mucus barrier dysfunction together with increased activities of speci c mucolytic microbes might impact oral tolerance.…”

Lentils and Yeast Fibers: A New Strategy to Mitigate Enterotoxigenic Escherichia coli (ETEC) Strain H10407 Virulence?

“…Unsurprisingly, they only seem to favor even more fermentation activities (e.g., fermentation gases). Lastly, since previous studies have elegantly shown in mice that dietary fiber intakes limited pathogen infection by protecting the mucus layer from degradation [ 36 , 142 , 143 ], we measured the total weight of mucin beads at the end of batch experiments. However, this previous hypothesis was not confirmed here, probably because of the use of simple batch experiments, which did not include goblet cells or allow the continuous supply of fiber sources or a renewal of luminal content.…”

Dietary fibre deprivation and bacterial curli exposure shift gut microbiome and exacerbate Parkinson's disease-like pathologies in an alpha-synuclein-overexpressing mouse

“…There is a great body of evidence on the impact of diet on microbial gut health and how it can influence the course of a disease. In vivo studies where rodents were fed a fibre deprived diet saw rapid shifts in microbial gut populations (Schroeder et al 2018;Desai et al 2016;Neumann et al 2021;Riva et al 2019). Accordingly our data showed decreased diversity, increased Firmicutes/Bacteriodetes ratios and altered abundance of many taxa.…”