Journal of Pediatrics and Neonatal Care Metabolomics in Experimental Neonatology Volume 2 Issue 4 - 2015 Afroditi Aggelina 1 , Angeliki Syggelou 1 , Athanasios Chalkias 1 , Apostolos Papalois 2 , Theodoros Xanthos 1 and Nicoletta Iacovidou 3 * 1 National and Kapodistrian University of Athens, Greece 2 ELPEN Research-Experimental Centre, Greece 3 Neonatal Department, National and Kapodistrian University of Athens, Greece *Corresponding author: Nicoletta Iacovidou, Neonatal Department, National and Kapodistrian University of Athens, Medical School, Pavlou Mela, 16233 Athens, Greece, Email: Received: July 10, 2015 | Published: August 28, 2015 Submit Manuscript | http://medcraveonline.com J Pediatr Neonatal Care, 2(4): 00086 Abbreviations: LPS: Lipopolysaccharide; OGD: Oxygen- Glucose Deprivation; ATP: Adenosine Triphosphate; NMR: Nuclear Magnetic Resonance; BAL: Bronchoalveolar Lavage; TCA: Tricarboxylic Acid; IUGR: Intrauterine Growth Restriction; ALI: Acute Lung Injury Introduction Metabolomics is a new ‘omics’ discipline, based on the detailed analysis of the host’s metabolic phenotype and the complex metabolic pathways with multiple network interactions. This metabolic fingerprint is considered as the gold standard for the profound understanding of the normal metabolic processes and of the alterations of the normal pathways. This ‘snapshot’ of the metabolic status may be a reliable tool for the prediction, early detection and monitoring the disease progression and may allow the identification of innovative interventions for delaying or reversing abnormal molecular changes. Non-human models have been used for the analysis of the metabolic status of the fetus or neonate in certain clinical conditions and existing data allow a more open-minded approach of studying and interpreting the fetal or neonatal metabolome. Therefore, metabolomics in experimental neonatology have gained a large impact in life sciences over the last decade. Discussion Non-human models have been used extensively for metabolomics analysis and various experimental protocols in metabolomics research have been published in literature (Table 1). In a newborn piglet model of hypoxia, authors successfully identified 13 urinary metabolites that differentiated hypoxic versus nonhypoxic animals. These metabolites were 1-methylnicotinamide, 2-oxoglutarate, alanine, asparagine, betaine, citrate, creatine, fumarate, hippurate, lactate, Nacetylglycine, N-carbamoyl-b-alanine, and valine, all directly related to cellular energy levels and metabolism. This metabolomic profile was able to blindly identify hypoxic and non-hypoxic animals correctly [1]. Metabolic studies including hypoxia and reoxygenation with different oxygen concentrations in newborn piglets highlighted strong variations in plasma metabolic parameters. Three groups of hypoxic newborn piglets received respectively 100% oxygen for 60 min, 21% oxygen for 60 min, 100% for 15 min and then 21% oxygen for 45min. In the hypoxic phase, lactate, low PH and base deficit were independent of the duration of hypoxia, while prolonged hypoxia led to low levels of free and total carnitine and an increase in long chain acyl-carnitines, which have toxic effect. In the reoxygenation phase, the subsequent hyperoxia was associated with a slower decline of Krebs cycle intermediates and an increase in lanosterol and in oxysteroles, both indicative of acute neuronal damage [2]. Fetal sheep and its plasma metabolome following inflammatory stimuli with E.coli lipopolysaccharide (LPS) were analyzed by Keller et al. [3] Induced hypoxia via LPS injection to the umbilical vein, resulted in various metabolic alterations. Krebs cycle intermediates, alanine and lactate, spermidine and oxysteroles with a known pro-apoptotic effect, were early increased while a decrease in hexoses was reported. Days after the hypoxic insult, there was a delayed opposite effect with remarkable hyperoxia, elevation of mediators of inflammation such as sphingomyelins, kynurenine, 3-hydroxykynurenine, putrescine, asymmetric dimethyl arginine, the latter well known for its role in microvascular tone and endothelial function. A similar non-human model experiment was described by Atzori and his co-workers; normocapnic hypoxia was induced in 4 groups of newborn piglets to either bradycardia or severe hypotension and different oxygen concentrations were used for resuscitation; urine samples were collected for metabolomics analysis. Despite reoxygenation 7 piglets out of the 10 piglets which became asystolic during the experiment, died. Urine analysis revealed differences in the metabolic profile of the urine collected before the induction of hypoxia between survivors and deaths; these included methyl guanidine and hydroxyisobutyric acid, malonate, urea, and creatinine, the three latter ones being well known for their role in aerobic metabolism, neurological Mini Review Abstract Metabolomics is a new ‘omics’ science, based on the thorough understanding of the metabolic fingerprint, thus recording the so called ‘metabolic signature’ of host’s cellular response. Recent data highlight that novel metabolic biomarkers reflect the multiple network interactions taking part in the host’s response to the disease burden, treatment intervention or life threatening conditions. Therefore, fetal or neonatal metabolome might be an early predictor of the ongoing metabolic procedures or molecular changes, thus a promising tool for early detection and prompt intervention. Experimental protocols on newborn animals have a significant role on lightening this foggy landscape. Keywords: Metabolomics; Neonatology; Experimental