MicroRNAs in adipocyte-derived extracellular vesicles in maternal and cord blood are related to neonatal adiposity

Abstract

Background: Maternal body size, nutrition, and hyperglycemia contribute to neonatal body size and composition. There is little information on maternal-fetal transmission of messages which influence fetal growth. We analyzed adipocyte-derived small extracellular vesicular (ADsEV) microRNAs in maternal and cord blood to explore their adipogenic potential. Methods: We studied 127 mother-neonate pairs (51 lean and 76 adipose neonates, in 68 NGT and 59 GDM pregnancies). Adiposity refers to highest tertile (T3) of sum of skinfolds in neonates of normal glucose tolerant (NGT) mothers, lean to lowest tertile (T1). ADsEV miRNAs from maternal and cord blood samples were profiled on Agilent 8*60K microarray. Differential expression (DE) of ADsEV miRNAs in adipose vs. lean neonates was studied before and after adjustment for maternal gestational diabetes mellitus (GDM), adiposity, and vitamin B12-folate status. Results: Multiple miRNAs were common in maternal and cord blood and positively correlated. We identified 24 maternal and 5 cord blood miRNAs differentially expressed (p≤0.1) in the adipose neonate group, and 19 and 26 respectively, in the adjusted analyses. Even though DE miRNAs were different in maternal and cord blood, they targeted similar adipogenic pathways (e.g., the forkhead box O (FOXO) family of transcription factors, mitogen‑activated protein kinase (MAPK) pathway, transforming growth factor beta (TGF-β) pathway). Maternal GDM and adiposity were associated with many DE ADsEV miRNAs. Conclusion: Our results suggest that the DE ADsEV miRNAs in mothers of adipose neonates are potential regulators of fetal adiposity. Further, the composition and functionality of miRNAs may be influenced by maternal hyperglycemia, adiposity, and micronutrient status during pregnancy .