Inflamm-aging microRNAs may integrate signals from food and gut microbiota by modulating common signalling pathways

Human gut microbiota, which comprises an extremely diverse and complex community of microorganisms inhabiting the intestinal tract, may be associated with inflammation and age-related chronic health conditions. However, the mechanism underlying this association is only recently beginning to emerge. Transfer and modulation of gene expression by diet-derived microRNAs (miRs) in mammals might be involved in this communication. Through a bioinformatics approach, using on line tools and repositories, we searched for evidences that food-containing miRs, actually involved in the modulation of the inflammatory process, (inflamma-miRs), may contribute to mediate the anti-inflammatory effects exerted by some foods through the modulation of aging-related pathways and gut microbiota composition in a bidirectional communication. Supported by a "Pubmed" search and our previous research, a trio of experimentally validated inflamma-miRs were considered: miR-155, miR-146a and miR-21. Our in silico study supports the hypothesis that these inflamma-miRs could modulate some pathways, such as lysine degradation and lengthening of fatty acids which are involved in the modulation of microbiota composition, i.e. prevotella, ruminococcus and oscillibacter and vice versa. Food homologues to human miR-21, miR-155 and miR-146a were found in cow fat, cow milk, and eggs suggesting that they may be able of targeting, and probably exacerbating, inflammation related pathways. If these data will be experimentally validated, they will further support the relevance of a nutraceutical approach for a healthy aging.