The perinatal transition of the circulating metabolome in a nonhuman primate

INTRODUCTION: The fetal-to-neonatal transition is one of the most complex processes in biological existence; much is unknown about this transition on the molecular and biochemical level. Based on growing metabolomics literature, we hypothesize that metabolomic analysis will reveal the key biochemical intermediates that change during the birth transition. RESULTS: Using two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC x GC-TOFMS), we identified 100 metabolites that changed during this transition. Of these 100 metabolites, 23 demonstrated significant change during the first 72 h. Of note, four intermediates of the tricarboxylic acid (TCA) cycle were identified (a-ketoglutaric acid, fumaric acid, malic acid, and succinyl-CoA), demonstrating a consistent rate of rise during the study. This may signify the transition of the neonate from a hypoxic in utero environment to an oxygen-rich environment. Important signaling molecules were also identified, including myo-inositol and glutamic acid. DISCUSSION: CC x GC-TOFMS was able to identify important metabolites associated with metabolism and signaling. These data can be used as a baseline for normal birth transition, which may aid in future perinatal research investigations. METHODS: Late-preterm Macaca nemestrina were delivered by hysterotomy, with plasma drawn from the cord blood and after birth at eight additional time points to 72 h of age.