Shared gene expression signatures between visceral adipose and skeletal muscle tissues are associated with cardiometabolic traits in children with obesity.

Obesity in children is related to the development of cardiometabolic complications later in life, where molecular changes of visceral adipose tissue (VAT) and skeletal muscle tissue (SMT) have been proven to be fundamental. The aim of this study is to unveil the gene expression architecture of both tissues in a cohort of Spanish boys with obesity, using a clustering method known as weighted gene co-expression network analysis. For this purpose, we have followed a multi-objective analytic pipeline consisting of three main approaches; identification of gene co-expression clusters associated with childhood obesity, individually in VAT and SMT (intra-tissue, approach I); identification of gene co-expression clusters associated with obesity-metabolic alterations, individually in VAT and SMT (intra-tissue, approach II); and identification of gene co-expression clusters associated with obesity-metabolic alterations simultaneously in VAT and SMT (inter-tissue, approach III). In both tissues, we identified independent and inter-tissue gene co-expression signatures associated with obesity and cardiovascular risk, some of which exceeded multiple-test correction filters. In these signatures, we could identify some central hub genes (e.g., NDUFB8, GUCY1B1, KCNMA1, NPR2, PPP3CC) participating in relevant metabolic pathways exceeding multiple-testing correction filters. We identified the central hub genes PIK3R2, PPP3C and PTPN5 associated with MAPK signaling and insulin resistance terms. This is the first time that these genes have been associated with childhood obesity in both tissues. Therefore, they could be potential novel molecular targets for drugs and health interventions, opening new lines of research on the personalized care in this pathology. This work generates interesting hypotheses about the transcriptomics alterations underlying metabolic health alterations in obesity in the pediatric population.

The protein S100A4 as a novel marker of insulin resistance in prepubertal and pubertal children with obesity.

BACKGROUND: S100A4 is a metastasis-associated protein also reported as a promising marker for dysfunctional white adipose tissue (WAT) and insulin resistance (IR) in adult and adolescent populations. OBJECTIVE: We aimed to evaluate the association between the protein S100A4 and obesity and IR in children and during pubertal development. DESIGN AND METHODS: The study design consisted of three cross-sectional populations of 249, 11 and 19 prepubertal children respectively (named study population 1, 2 and 3), and a longitudinal population of 53 girls undergoing sexual maturation (study population 4). All subjects were classified into experimental groups according to their sex, obesity and IR status. All study populations counted on anthropometry, glucose, and lipid metabolism, inflammation and cardiovascular biomarkers as well as S100A4 plasma levels measured. The study population 1 was intended as the discovery population in which to elucidate the relationship between Obesity-IR and S100A4 plasma levels in prepubertal children. The cross-sectional populations 2 and 3 further counted on WAT gene expression data for investigating the molecular basis of this association. Instead, the longitudinal study population 4 presented blood whole-genome DNA methylation data at each temporal record, allowing deepening into the Obesity-IR-S1004 relationship during puberty as well as deciphering plausible epigenetic mechanisms altering S100A4 plasma levels. RESULTS: S100A4 plasma levels were strongly associated with several metabolic and anthropometric outcomes, namely IR, in prepubertal non-diabetic obese children. We also found highly significant positive associations during the course of puberty between the increase in S100A4 levels and the increase in HOMA-IR (P = 0.0003, FDR = 0.005) and insulin levels (P = 0.0003, FDR = 0.005). Methylation in two-enhancer related CpG sites of the S100A4 region (cg07245635 and cg10447638) was associated with IR biomarkers at the prepubertal stage and with longitudinal changes in these measurements. We further reported an association between visceral WAT (vWAT) S100A4 expression and HOMA-IR, insulin levels and BMI Z-Score, but not with circulating S100A4. CONCLUSIONS: We report for the first time the association of S100A4 with IR and WAT dysfunction in prepubertal populations as well as how the change in plasma S100A4 levels accompanies longitudinal trajectories of IR in children during pubertal development. Moreover, we propose epigenetic changes in two methylation sites and an altered S100A4 vWAT expression as plausible molecular mechanisms underlying this disturbance in obesity.

Topiramate plus Cooling for Hypoxic-Ischemic Encephalopathy: A Randomized, Controlled, Multicenter, Double-Blinded Trial.

BACKGROUND AND OBJECTIVES: Therapeutic interventions to improve the efficacy of whole-body cooling for hypoxic-ischemic encephalopathy (HIE) are desirable. Topiramate has been effective in reducing brain damage in experimental studies. However, in the clinical setting information is limited to a small number of feasibility trials. We launched a randomized controlled double-blinded topiramate/placebo multicenter trial with the primary objective being to reduce the antiepileptic activity in cooled neonates with HIE and assess if brain damage would be reduced as a consequence. STUDY DESIGN: Neonates were randomly assigned to topiramate or placebo at the initiation of hypothermia. Topiramate was administered via a nasogastric tube. Brain electric activity was continuously monitored. Topiramate pharmacokinetics, energy-related and Krebs' cycle intermediates, and lipid peroxidation biomarkers were determined using liquid chromatography-mass spectrometry and MRI for assessing brain damage. RESULTS: Out of 180 eligible patients 110 were randomized, 57 (51.8%) to topiramate and 53 (48.2%) to placebo. No differences in the perinatal or postnatal variables were found. The topiramate group exhibited less seizure burden in the first 24 h of hypothermia (topiramate, n = 14 [25.9%] vs. placebo, n = 22 [42%]); needed less additional medication, and had lower mortality (topiramate, n = 5 [9.2%] vs. placebo, n = 10 [19.2%]); however, these results did not achieve statistical significance. Topiramate achieved a therapeutic range in 37.5 and 75.5% of the patients at 24 and 48 h, respectively. A significant association between serum topiramate levels and seizure activity (p < 0.016) was established. No differences for oxidative stress, energy-related metabolites, or MRI were found. CONCLUSIONS: Topiramate reduced seizures in patients achieving therapeutic levels in the first hours after treatment initiation; however, they represented only a part of the study population. Our results warrant further studies with higher loading and maintenance dosing of topiramate.

Estrés oxidativo en la asfixia perinatal y la encefalopatía hipóxico-isquémica / Oxidative stress in perinatal asphyxia and hypoxic-ischaemic encephalopathy

La asfixia intraparto es una de las causas más frecuentes de muerte neonatal precoz pero también puede, en los supervivientes, evolucionar a una encefalopatía hipóxico-isquémica responsable de una elevada morbilidad neurológica. La presencia de episodios de hipoxia-isquemia prolongados conduce a un rápido agotamiento energético en los tejidos exclusivamente dependientes del metabolismo aeróbico, como el sistema nervioso central. El déficit energético conlleva una paralización de las bombas ATP-dependientes y subsiguiente pérdida del potencial neuronal transmembrana. La población neuronal de las regiones más sensibles del SNC mueren por necrosis, mientras que en otras áreas se produce una hiperexcitabilidad neuronal con entrada masiva de calcio iónico, activación de NO-sintasa, generación de radicales libres que alteran el funcionamiento mitocondrial, provocando un fallo energético secundario y muerte neuronal por apoptosis. Recientemente se ha propuesto una tercera fase en la que factores como la inflamación persistente y los cambios epigenéticos causarían un bloqueo de la maduración de los oligodendrocitos, alteración de la neurogénesis, del crecimiento axonal y de la sinaptogénesis. En este contexto, el estrés oxidativo va a tener un papel protagonista como responsable tanto en causar daño directo al SNC como en activar cascadas metabólicas conducentes a la apoptosis e inflamación. La hipotermia moderada precoz, al preservar las reservas energéticas y disminuir la formación de especies reactivas de oxígeno, atenuará el daño cerebral posreanimación. La combinación de la hipotermia con terapias coadyuvantes para modular el estrés oxidativo podría contribuir a mejorar el pronóstico

Birth asphyxia is one of the principal causes of early neonatal death. In survivors it may evolve to hypoxic-ischaemic encephalopathy and major long-term neurological morbidity. Prolonged and intense asphyxia will lead to energy exhaustion in tissues exclusively dependent on aerobic metabolism, such as the central nervous system. Energy deficit leads to ATP-dependent pumps blockage, with the subsequent loss of neuronal transmembrane potential. The most sensitive areas of the brain will die due to necrosis. In more resistant areas, neuronal hyper-excitability, massive entrance of ionic calcium, activation of NO-synthase, free radical generation, and alteration in mitochondrial metabolism will lead to a secondary energy failure and programmed neuronal death by means of the activation of the caspase pathways. A third phase has recently been described that includes persistent inflammation and epigenetic changes that would lead to a blockage of oligodendrocyte maturation, alteration of neurogenesis, axonal maturation, and synaptogenesis. In this scenario, oxidative stress plays a critical role causing direct damage to the central nervous system and activating metabolic cascades leading to apoptosis and inflammation. Moderate whole body hypothermia to preserve energy stores and to reduce the formation of oxygen reactive species attenuates the mechanisms that lead to the amplification of cerebral damage upon resuscitation. The combination of hypothermia with coadjuvant therapies may contribute to improve the prognosis

Efficacy of Paracetamol in Closure of Ductus Arteriosus in Infants under 32 Weeks of Gestation.

BACKGROUND: Standard medical treatment for patent ductus arteriosus (PDA) closure has been indomethacin/ibuprofen or surgical ligation. Up to date, new strategies have been reported with paracetamol. The aim of this study was to present our experience with intravenous paracetamol for closing PDA in preterm neonates presenting contraindication to ibuprofen or ibuprofen had failed and no candidates for surgical ligation because of huge instability. MATERIALS AND METHODS: We conducted a retrospective case series study in a neonatal intensive care unit from a tertiary hospital. 9 preterm infants ≤32 weeks of gestational age with hemodynamically significant PDA (hsPDA) were enrolled. They received 15 mg/kg/6h intravenous paracetamol for ductal closure. Demographic data and transaminase levels before and after treatment were collected. RESULTS: 30 preterm babies were diagnosed of hsPDA. 11/30 received ibuprofen with closure in 81.1%. 9 received intravenous paracetamol mainly due to bleeding disorders or thrombocytopenia. Successful closure on paracetamol was achieved in seven of nine babies (77.7%). There was a significant increase in transaminase levels in two patients. They required no treatment for normalization. CONCLUSION: Paracetamol is an effective option in closure PDA. It should be a first-line therapeutic option when there are contraindications for ibuprofen treatment. Transaminases must be checked during treatment.

[Oxidative stress in perinatal asphyxia and hypoxic-ischaemic encephalopathy]. / Estrés oxidativo en la asfixia perinatal y la encefalopatía hipóxico-isquémica.

Birth asphyxia is one of the principal causes of early neonatal death. In survivors it may evolve to hypoxic-ischaemic encephalopathy and major long-term neurological morbidity. Prolonged and intense asphyxia will lead to energy exhaustion in tissues exclusively dependent on aerobic metabolism, such as the central nervous system. Energy deficit leads to ATP-dependent pumps blockage, with the subsequent loss of neuronal transmembrane potential. The most sensitive areas of the brain will die due to necrosis. In more resistant areas, neuronal hyper-excitability, massive entrance of ionic calcium, activation of NO-synthase, free radical generation, and alteration in mitochondrial metabolism will lead to a secondary energy failure and programmed neuronal death by means of the activation of the caspase pathways. A third phase has recently been described that includes persistent inflammation and epigenetic changes that would lead to a blockage of oligodendrocyte maturation, alteration of neurogenesis, axonal maturation, and synaptogenesis. In this scenario, oxidative stress plays a critical role causing direct damage to the central nervous system and activating metabolic cascades leading to apoptosis and inflammation. Moderate whole body hypothermia to preserve energy stores and to reduce the formation of oxygen reactive species attenuates the mechanisms that lead to the amplification of cerebral damage upon resuscitation. The combination of hypothermia with coadjuvant therapies may contribute to improve the prognosis.

Evolution of Energy Related Metabolites in Plasma from Newborns with Hypoxic-Ischemic Encephalopathy during Hypothermia Treatment.

Therapeutic hypothermia (TH) initiated within 6 h from birth is the most effective therapeutic approach for moderate to severe hypoxic-ischemic encephalopathy (HIE). However, underlying mechanisms and effects on the human metabolism are not yet fully understood. This work aims at studying the evolution of several energy related key metabolites in newborns with HIE undergoing TH employing gas chromatography - mass spectrometry. The method was validated following stringent FDA requirements and applied to 194 samples from a subgroup of newborns with HIE (N = 61) enrolled in a multicenter clinical trial (HYPOTOP) for the determination of lactate, pyruvate, ketone bodies and several Krebs cycle metabolites at different sampling time points. The analysis of plasma samples from newborns with HIE revealed a decrease of lactate, pyruvate and ß-hydroxybutyrate concentrations, whereas rising malate concentrations were observed. In healthy control newborns (N = 19) significantly lower levels of pyruvate and lactate were found in comparison to age-matched newborns with HIE undergoing TH, whereas acetoacetate and ß-hydroxybutyrate levels were clearly increased. Access to a validated analytical method and a controlled cohort of newborns with HIE undergoing hypothermia treatment for the first time allowed the in-depth study of the evolution of key metabolites of metabolic junctions in this special population.

Genome-wide expression in visceral adipose tissue from obese prepubertal children.

Characterization of the genes expressed in adipose tissue (AT) is key to understanding the pathogenesis of obesity and to developing treatments for this condition. Our objective was to compare the gene expression in visceral AT (VAT) between obese and normal-weight prepubertal children. A total of fifteen obese and sixteen normal-weight children undergoing abdominal elective surgery were selected. RNA was extracted from VAT biopsies. Microarray experiments were independently performed for each sample (six obese and five normal-weight samples). Validation by quantitative PCR (qPCR) was performed on an additional 10 obese and 10 normal-weight VAT samples. Of 1276 differentially expressed genes (p < 0.05), 245 were more than two-fold higher in obese children than in normal-weight children. As validated by qPCR, expression was upregulated in genes involved in lipid and amino acid metabolism (CES1, NPRR3 and BHMT2), oxidative stress and extracellular matrix regulation (TNMD and NQO1), adipogenesis (CRYAB and AFF1) and inflammation (ANXA1); by contrast, only CALCRL gene expression was confirmed to be downregulated. In conclusion, this study in prepubertal children demonstrates the up- and down-regulation of genes that encode molecules that were previously proposed to influence the pathogenesis of adulthood obesity, as well as previously unreported dysregulated genes that may be candidate genes in the aetiology of obesity.