Search for Bovine miRNA Transference to Humans

Background: Foods derived from plants and animals contain miRNAs, and, some reports have detected diet-derived miRNAs circulating in mammalian serum. It is still unclear if the miRNAs present in food can be absorbed by the gastrointestinal tract and brought to the tissues to perform regulatory functions. The transfer of functional exogenous miRNA has been demonstrated in bacterial and viral infections but it is less well characterized in mammals. Edible bovine tissues contain unique profiles of human-homologous miRNAs that withstand cooking. If miRNAs from other species can cross the gastrointestinal barrier, it could have implications in gene regulation and health. Objective: Determine whether miRNAs from beef cross the gastrointestinal barrier and are transferred to human plasma. Methods: The investigators obtained fasting plasma from 29 healthy subjects divided in two groups: the omnivore group (6 men, 8 women) and the vegan group (8 men, 7 women; control group). Each participant was given a standard meal with or without beef depending on their group, then the plasma was collected at 2, 4 and 6 hours after the meal. The changes in the levels of of miR-1, miR-10b, miR-22, miR-92 and miR-192 were analysed by quantitative Polymerase Chain Reaction (qPCR).