Comparison of the effects of five dietary fibers on mucosal transcriptional profiles, and luminal microbiota composition and SCFA concentrations in murine colon

Scope: The aim of our study was to investigate and compare the effects of five fibers on the mucosal transcriptome, together with alterations in the luminal microbiota composition and SCFA concentrations in the colon. Methods and results: Mice were fed fibers that differed in carbohydrate composition or a control diet for 10 days. Colonic gene expression profiles and luminal microbiota composition were determined by microarray techniques, and integrated using multivariate statistics. Our data showed a distinct reaction of the host and microbiota to resistant starch, a fiber that was not completely fermented in the colon, whereas the other fibers induced similar responses on gene expression and microbiota. Consistent associations were revealed between fiber-induced enrichment of Clostridium cluster IV and XIVa representatives, and changes in mucosal expression of genes related to energy metabolism. The nuclear receptor PPAR-γ was predicted to be an important regulator of the mucosal responses. Conclusion: Results of this exploratory study suggest that despite different sources and composition, fermentable fibers induce a highly similar mucosal response that may at least be partially governed by PPAR-γ.