Detection and quantification of miRNA 148a expression in infant formulas

MiRNA 148a, which is associated with various biological processes such as immunity and cell differentiation, is one of the most abundant miRNAs in breast milk. This study aimed to determine the amount of miRNA 148a in different infant formulas, which are used for infants who cannot receive breast milk. The study analyzed 20 formulas, including stage one infant formulas (0-6 months of age), stage two follow-up formulas (6-12 months of age), stage three toddler formulas (above 12 months of age), and premature ones, analyzing miRNA 148a expression and qPCR miRNA gene expression, with significance set at p < 0.05. The expression levels of miRNA 148a in different infant formulas were compared, and no statistically significant difference was observed (p > 0.05). Also, there was no difference in relative miRNA 148a expression across formulas with and without probiotics (p > 0.05). Protein levels in probiotic formulas (0 month-1 year+) were positively correlated with relative miRNA 148a expression (p = 0.022). Although miRNA 148a expression has been shown to be present in formulas, it has been revealed that the amount is low compared to breast milk in line with the literature. In this direction, it is important to increase current data on the mechanisms of action of miRNAs in breast milk and the efforts to ensure that infant formulas reach a composition closest to breast milk in line with their biological effects. PRACTICAL APPLICATION: The miRNAs found in exosomal compounds in human breast milk are very diverse in terms of number and health effects, and can control various biological processes in cells, including immunity, cell differentiation, and apoptosis. One of these is miRNA 148a, which is the most abundant in human breast milk. For this reason, in this study, the miRNA 148a content of infant formulas, which are commonly used in healthy babies who cannot receive enough human breast milk (breastfeeding recommended for at least 6 months and up to 2 years) for a valid reason, was analyzed. In conclusion, miRNA expression has been detected in infant formulas, but it has been shown that this expression is at a low level.