MiRNA-320a is less expressed and miRNA-148a more expressed in preterm human milk compared to term human milk

•MiRNA-320 was more highly expressed in in colostrum of full-term than in preterm HM.•The expression of miRNA-148 was higher in colostrum of preterm than in full-term HM.•MiRNA-320 expression was upregulated in cells incubated with milk exosomes.•MiRNA-148 expression was upregulated in cells incubated with milk exosomes.•Incubation of cells with HM exosomes led to a decrease in DNMT1 and FASN expression.•MiRNA expression in HM can affect biological functions in infants.•MiRNA in HM may serve as a nutritional therapeutic target.