The impact of dietary cellulose on transcriptional profiles of colonic epithelial cells during inflammation.

Purpose: Although dietary cellulose is considered health promoting, there is still a lack of understanding of cellular and molecular mechanisms. The aim of this study was to shed light on possible effects of the fiber on key players in intestinal homeostasis, including intestinal epithelial cells. Method: Mice were fed a diet containing cellulose as the only source of fiber (CD, control diet) or a fiber free diet (FFD, fiber-free diet) for four weeks and then treated with dextran sulphate sodium in the drinking water for five days. To ensure that gene signatures were derived from colonic epithelial cells and not from contaminating lymphocytes, RAG1 KO mice deficient in intraepithelial lymphocytes were used. Results: The analysis of differential expressed genes of colonic epithelial cells revealed multiple effects of dietary cellulose on the transcriptional profiles. In addition, cellulose caused a distinct clustering when comparing signature genes of different epithelial cell types. Conclusion: This study demonstrated that dietary cellulose impacts transcriptional programs in colonic epithelial cells during inflammation. Overall design: Colonic epithelial mRNA profiles of RAG1 KO mice receiving a cellulose-containing (n=5) and fiber-free diet (n=6) during inflammation.