Early Postnatal Metabolic Profile in Neonates With Different Birth Weight Status: A Pilot Study

Abstract

Introduction: Restricted or enhanced intrauterine growth is associated with elevated risks of early and late metabolic problems in humans. Metabolomics based on amino acid and carnitine/acylcarnitine profile may have a role in fetal and early postnatal energy metabolism. In this study, the relationship between intrauterine growth status and early metabolomics profile was evaluated.Materials and Methods: A single-center retrospective cohort study was conducted. Three hundred and sixty-one newborn infants were enrolled into the study, and they were grouped according to their birth weight percentile as small for gestational age (SGA, n = 69), appropriate for gestational age (AGA, n = 168), and large for gestational age (LGA, n = 124) infants. In all infants, amino acid and carnitine/acylcarnitine profiles with liquid chromatography-tandem mass spectrometry (LC-MS/MS) were recorded and compared between groups.Results: LGA infants had higher levels of glutamic acid and lower levels of ornithine, alanine, and glycine (p < 0.05) when compared with AGA infants. SGA infants had higher levels of alanine and glycine levels when compared with AGA and LGA infants. Total carnitine, C0, C2, C4, C5, C10:1, C18:1, C18:2, C14-OH, and C18:2-OH levels were significantly higher and C3 and C6-DC levels were lower in SGA infants (p < 0.05). LGA infants had higher C3 and C5:1 levels and lower C18:2 and C16:1-OH levels (p < 0.05). There were positive correlations between free carnitine and phenylalanine, arginine, methionine, alanine, and glycine levels (p < 0.05). Also, a positive correlation between ponderal index and C3, C5-DC, C14, and C14:1 and a negative correlation between ponderal index and ornithine, alanine, glycine, C16:1-OH, and C18:2 were shown.Conclusion: We demonstrated differences in metabolomics possibly reflecting the energy metabolism in newborn infants with intrauterine growth problems in the early postnatal period. These differences might be the footprints of metabolic disturbances in future adulthood.

Metabolomics of a neonatal cohort from the Alliance for Maternal and Newborn Health Improvement biorepository: Effect of preanalytical variables on reference intervals

“…Differing to the Turkish findings, in our study the DBS alanine levels were higher in AGA (247.71 ±100.32 μmol/L) as compared to SGA newborns (232.16±80.64 μmol/L); p value 0.04. Alanine is the key product of lactate metabolism and assists in glucose homeostasis, and higher levels of alanine in preterm neonates have been reported to increase the risk of diseases related to metabolic syndrome in later life [34]. We also noted higher mean alanine levels in full terms as compared to preterm with a mean difference of ±22 μmol/L.…”

Metabolomics Applied to Cord Serum in Preeclampsia Newborns: Implications for Neonatal Outcomes

“…Sarcosine is metabolized to glycine by sarcosine dehydrogenase. A latest study of neonates also found elevated glycine in SGA neonates ( 38 ). From the perspective of nutrition, it is speculated that this amino acid alteration, we found, may reflect the enhanced decomposition of protein to make up for the insufficient energy supply of PE placenta.…”

“…Mitochondrial dysfunction makes it difficult to consume fat, resulting in carnitine accumulation ( 59 ). Beken et al also found abnormal carnitine in SGA neonates, including reduced propionyl carnitine and methylglutaryl carnitine ( 38 ). Another study reported an increased carnitine concentration in neonates with a high body fat rate ( 60 ).…”

Longitudinal associations of pre-pregnancy BMI and gestational weight gain with maternal urinary metabolites: an NYU CHES study

“…In addition, GWG was associated with concentrations of short-chain acylcarnitines, C5:1, C5-DC, and C5-M-DC. While research has not directly linked short-chain acylcarnitines with GWG, studies have found associations between short-chain acylcarnitines and birthweight, a common outcome related to GWG, as well as fetal adiposity ( 51 , 52 ). One study reported correlations of neonatal plasma levels of C5:1 with LGA status as well as of C5-DC levels with ponderal index, but not in the same direction as the association we observed ( 51 ).…”

“…While research has not directly linked short-chain acylcarnitines with GWG, studies have found associations between short-chain acylcarnitines and birthweight, a common outcome related to GWG, as well as fetal adiposity ( 51 , 52 ). One study reported correlations of neonatal plasma levels of C5:1 with LGA status as well as of C5-DC levels with ponderal index, but not in the same direction as the association we observed ( 51 ). This discrepancy could be due to differences in biofluid medium, which have been theorized to influence the directionality of effects in metabolomics research ( 19 ).…”