Dietary cellulose induces anti-inflammatory immunity and transcriptional programs via maturation of the intestinal microbiota

• Main Authors: Florence Fischer, Rossana Romero, Anne Hellhund, Uwe Linne, Wilhelm Bertrams, Olaf Pinkenburg, Hosam Shams Eldin, Kai Binder, Ralf Jacob, Alesia Walker, Bärbel Stecher, Marijana Basic, Maik Luu, Rouzbeh Mahdavi, Anna Heintz-Buschart, Alexander Visekruna, Ulrich Steinhoff
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2020-11-01
• Series: Gut Microbes
• Subjects: cellulose; insoluble fiber; microbiota maturation; microbial diversity; bile acids; mucosal homeostasis; inflammation; alistipes; reg3γ; il-22
• Online Access: http://dx.doi.org/10.1080/19490976.2020.1829962
• ISSN: 1949-0976; 1949-0984

Although it is generally accepted that dietary fiber is health promoting, the underlying immunological and molecular mechanisms are not well defined, especially with respect to cellulose, the most ubiquitous dietary fiber. Here, the impact of dietary cellulose on intestinal microbiota, immune responses and gene expression in health and disease was examined. Lack of dietary cellulose disrupted the age-related diversification of the intestinal microbiota, which subsequently remained in an immature state. Interestingly, one of the most affected microbial genera was Alistipes which is equipped with enzymes to degrade cellulose. Absence of cellulose changed the microbial metabolome, skewed intestinal immune responses toward inflammation, altered the gene expression of intestinal epithelial cells and mice showed increased sensitivity to colitis induction. In contrast, mice with a defined microbiota including A. finegoldii showed enhanced colonic expression of intestinal IL-22 and Reg3γ restoring intestinal barrier function. This study supports the epidemiological observations and adds a causal explanation for the health promoting effects of the most common biopolymer on earth.