Metabolism-related microRNAs in maternal breast milk are influenced by premature delivery

Abstract

Background Maternal breast milk (MBM) is enriched in microRNAs, factors that regulate protein translation throughout the human body. MBM from mothers of term and preterm infants differ in nutrient, hormone, and bioactive factor composition, but the microRNA differences between these groups have not been compared. We hypothesized that gestational age at delivery influences microRNA in MBM, particularly microRNAs involved in immunologic and metabolic regulation. Methods MBM from mothers of premature infants (pMBM) obtained 3–4 weeks post-delivery was compared with MBM from mothers of term infants obtained at birth (tColostrum) and 3–4 weeks post-delivery (tMBM). The microRNA profile in lipid and skim fractions of each sample was evaluated with high-throughput sequencing. Results The expression profiles of nine microRNAs in lipid and skim pMBM differed from tMBM. Gene targets of these microRNAs were functionally related to elemental metabolism and lipid biosynthesis. The microRNA profile of tColostrum was also distinct from pMBM, but clustered closely with tMBM. Twenty-one microRNAs correlated with gestational age demonstrated limited relationships with method of delivery, but not other maternal infant factors. Conclusion Premature delivery results in a unique MBM microRNA profile with metabolic targets. This suggests preterm milk may have adaptive functions for growth in premature infants.

Breast Milk, a Source of Beneficial Microbes and Associated Benefits for Infant Health

“…Zhou et al also noted immune related miRNAs were rich in breast milk exosomes. As mentioned previously, the microRNA profile differs between full-term and preterm breast milk [128]. Carney et al also noted that the gene targets of the nine microRNAs that differed between both groups influenced metabolic processes such as lipid metabolism.…”

“…The microRNA profile of human milk has also been compared between mothers of full-term versus mothers of preterm infants. A study by Carney et al identified differences in the expression profiles of nine miRNAs in the skim milk and lipid fractions of preterm breast milk when compared to full-term samples [128]. Furthermore, a recent investigation by Shiff et al noted that miRNA-320 was expressed less in preterm milk while miRNA-148 was more expressed when compared to full-term milk [129].…”

Milk MicroRNAs in Health and Disease

“…Finally, a recent study on milk microRNAs profiles during premature delivery was not able to validate microRNAs as candidates for early diagnosis of this condition (Carney et al., ).…”

“…In milk, microRNA expression was related to mammary gland conditions, including infections (Iannaccone et al., ; Lai et al., , ; Sun et al., ), cancer (Decmann et al., ; Do Canto et al., ; Hesari et al., ), pregnancy and lactation status (Carney et al., ; Perri et al., ; Schanzenbach et al., ), and maternal diet (Chen et al., ). Therefore microRNAs in milk were studied for their potential as biomarkers (Gustafson, Tyryshkin, & Renwick, ; Melnik & Schmitz, ) such as quality controls of commercial milk (Oh et al., ).…”

“…The majority of studies have only investigated this matter in silico using microRNA‐target identification tools and associated pathways/gene ontology analysis (Alsaweed et al., , ; Cai et al., , ; Carney et al., ; Chen et al., , , ; Chokeshaiusaha, Sananmuang, Puthier, & Nguyen, ; Do, Li, Dudemaine, & Ibeagha‐Awemu, ; Golan‐Gerstl, Elbaum Shiff, et al., ; Gu et al., , ; Hou et al., ; Kang et al., ; Li et al., , ; Liao et al., ; Liu et al., ; Lukasik & Zielenkiewicz, ; Modepalli et al., ; Munch et al., ; Shen et al., ; Simpson et al., ; Sun et al., ; Wang et al., ; Zhang et al., ; Zhou et al., ).…”