1H-NMR metabolic profiling of human neonatal urine

Abstract

The measurement of different urine components and their changes over time may provide comprehensive and early information about perinatal metabolic processes and physiological changes. We hypothesized that (1) H-NMR-spectroscopy generating a complex spectral profile without pre-selection of urinary metabolites could identify metabolites determining the neonatal physiological status and discriminating between different metabolic states. We studied spot urine of three groups of neonates (healthy term-born, term-born with non-specific bacterial infections, and preterm neonates) for the first 6 days of life using (1) H-NMR-spectroscopy. In the group of healthy neonates metabolites changing were identified and their excretion patterns compared between groups. Six metabolites indicating physiological changes were identified: N-methylnicotinamide (NAD (+)-pathway), formate, hippurate, betaine (kidney development), taurine (neuronal development), and bile acids (hepatic clearance). While the dynamic changes over the first 6 days were the same for all metabolites in both groups of term-born neonates, the excretion of N-methylnicotinamide and taurine was significantly higher in preterm neonates compared to healthy term neonates and neonates with bacterial infections from the third day after birth (P < 0.05). Urine analysis using (1) H-NMR-spectroscopy could identify markers for perinatal metabolic changes. Further studies have to clarify if the proposed physiological interpretation will correlate with long-term physiological development.