Consumption of 1-Kestose Upregulates MicroRNA-200 and-192/215 Families in Lamina Propria Leukocytes of the Murine Large Intestine

By comparing germ-free mice and specific pathogen-free mice, we recently demonstrated that the presence of gut commensals upregulates microRNA-200 family members in lamina propria leukocytes (LPL) of the murine large intestine. The present study tested whether the consumption of 1-kestose (KES), an indigestible oligosaccharide that alters gut microbiota composition, influences the microRNA expression in the LPL. Supplementation of KES (4%) in drinking water for 2 wk increased the levels of miR-182-5p,-205-5p,-290a-5p, miR-200 family members (miR-141-3p,-200a-3p,-200b-3p,-200c-3p, and-429-3p) as well as miR-192/215 family members (miR-192-5p,-194-5p, and-215-5p) as determined by microarray analysis in large intestinal LPL of C57BL/6 mice. Quantitative reverse transcription-PCR further confirmed the increase in miR-192-5p,-194-5p,-200a-3p,-200b-3p,-200c-3p,-205-5p, and 215-5p. KES consumption significantly increased Bifidobacterium pseudolongum in the cecal contents. In a separate experi-ment, intragastric administration of B. pseudolongum (10⁹ CFU/d) for 7 d increased the levels of miR-182-5p,-194-5p, and-200a-3p and tended to increase the levels of miR-200b-3p,-215-5p, and-429-3p. These results suggest that dietary KES influences miRNA expression in the large intestinal LPL, which may be associated with the increased population of B. pseudolongum.