MICRORNAs ARE ABSORBED IN BIOLOGICALLY MEANINGFUL AMOUNTS FROM NUTRITIONALLY RELEVANT DOSES OF COW’S MILK AND CHICKEN EGGS AND AFFECT GENE EXPRESSION IN PERIPHERAL BLOOD MONONUCLEAR CELLS, CELL CULTURES, AND MOUSE LIVERS

1MicroRNAs (miRs, miRNAs) play central roles in gene regulation. Previously, we2reported that miRNAs from pasteurized, store-bought bovine milk have biological3activity in humans. Here we assessed the effects of milk processing, storage, somatic cell4content, and handling by consumers on the degradation of miRNAs in milk; we also5quantified miRNAs in dairy products. Pasteurization and homogenization caused a 63%6loss of miR-200c, whereas a 67% loss observed for miR-29b was statistically significant7only in skim milk. Effects of cold storage and somatic cell content were quantitatively8minor (<2% loss). Heating in the microwave caused a 40% loss of miR-29b but no loss of9miR-200c. Milk fat content had no effect on miRNA stability during storage and10microwave heating. The concentrations of miRNAs in dairy products were considerably11lower than in store-bought milk. We conclude that processing of milk by dairies and12handling by consumers causes a significant loss of miRNAs.1314