MicroRNAs in chicken eggs are bioavailable in healthy adults and can modulate mRNA expression in peripheral blood mononuclear cells.

Abstract

Previous research in our lab demonstrated the bioavailability of milk-borne microRNAs following milk consumption by healthy adults. An important question left unanswered from our previous work was if this phenomenon is unique to milk or if other foods could also be a source of exogenous microRNA. To explore this possibility, we tested the hypothesis that chicken egg microRNAs are bioavailable following consumption of hard boiled eggs by healthy adult humans. Plasma levels of miR-181a and miR-181b increased 9 hours after egg consumption to 146% and 304% above baseline levels, respectively (as per qRT-PCR). Abundance of miR-181b is 223% higher than miR-181a in eggs, suggesting that the increase in plasma microRNAs depended on the dose consumed. Importantly, the plasma concentrations of the chicken-specific microRNA, gga-miR-1451-5p, increased from below detection limit at hour zero to 1 fmol/L at hour nine. Expression of BCL2A1, an experimentally validated target of miR-181b, was 16% lower in human lymphocytes 9 hours after egg consumption. A bioinformatics analysis showed chicken egg microRNAs target at least 28 KEGG pathways. We conclude that chicken egg microRNAs are bioavailable and have the potential to influence endogenous gene expression in humans following consumption of physiologically relevant doses of eggs. Supported by USDA/NIFA, USDA/Egg Nutrition Center, NIH 1P20GM104320.