Fecal mirnas, new mediators of host-microbiota interaction in inflammatory bowel disease
Growing evidences indicate that microRNAs (miRNAs) are present in various body fluids and contribute to cell-cell communication. My previous studies identified circulating miRNAs as efficient tool for the diagnosis and surveillance of Inflammatory Bowel Disease (IBD). Interestingly, miRNAs are secreted into the intestinal lumen where thousands of different bacterial species are present and confer important benefits to the host. This proximity prompted us to speculate that miRNAs and bacteria interact, playing a role in the host/microbiota relationship. My preliminary data generated to date demonstrate that fecal miRNAs are altered during intestinal inflammation in association with an alteration of microbiota composition, and we recently reported that exogenously administered miRNAs have the potential to alter microbiota composition and function. Here, our central hypothesis is that fecal miRNAs are mediators of host-microbiota interactions and therefore modulate intestinal inflammation. On the basis of this overarching hypothesis, I now propose to determine the role played by the intestinal microbiota in miRNA-mediated modulation of intestinal inflammation (objective 1: mechanism); Investigate the ability of specific miRNAs / anti-miRNAs to modulate intestinal inflammation. (objective 2: therapeutic) and to identify whether fecal miRNAs are indicators of microbiota and intestinal healthiness in IBD patients (objective 3: translational). We envision that the proposed experiments could identify a new role for miRNAs in manipulating the intestinal microbiota hence leading to the development of new therapeutic strategies.