Consequences of postnatal stress: maternal separation in rats induces long-lasting changes on glutamate transporters

Background: There is increasing evidence that environmental factors, particularly stressful events experienced early in life, increase the risk of developing a psychiatric illness and/or a behavioural disorder. The aim of this study was to evaluate the effects of acute and chronic maternal separation (AMS and CMS) plus cold stress on the expression patterns of Glutamate Transporters (TGlus) in the developing and young adult Central Nervous System (CNS). As regulation of Glutamate (Glu) extracellular levels is of key importance, sodium-dependent Glu uptake using synaptosome-enriched fractions isolated from Frontal Cortex (FC) and Hippocampus (Hic) was also studied. Results: In animals under AMS stress found that Glu uptake decreases with respect to control groups. Meanwhile in CMS did not observe changes on Glu uptake in adult animals. These data would suggest the existence of an adaptive mechanism that could compensate the effect of AMS and CMS plus cold stress on glutamate uptake. Western blotting was performed in homogenates prepared from FC and Hic from both neonate and young adult rat brains. These blots exposed that homogenates include GLT-1 and EAAC-1 proteins and their levels varied in different areas of the rat brain and with the age of animals. Conclusions: During early postnatal life, exposure to various stressors lead to the development of various neurological, psychiatric, neurodegenerative and behavioral disorders, expressible in adult life in the case of chronic stress. These results demonstrate that adverse early life events have profound and persistent effects on brain function and may represent a risk factor for the development of psychopathology later life.Fil: Odeon, Maria Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); ArgentinaFil: Salatino, Adrián Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); ArgentinaFil: Acosta, Gabriela Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas (i); Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Ciencias Biológicas. Cátedra de Fisiopatología; Argentin

Pleiotropy within gene variants associated with nonalcoholic fatty liver disease and traits of the hematopoietic system

Genome-wide association studies of complex diseases, including nonalcoholic fatty liver disease (NAFLD), have demonstrated that a large number of variants are implicated in the susceptibility of multiple traits - a phenomenon known as pleiotropy that is increasingly being explored through phenome-wide association studies. We focused on the analysis of pleiotropy within variants associated with hematologic traits and NAFLD. We used information retrieved from large public National Health and Nutrition Examination Surveys, Genome-wide association studies, and phenome-wide association studies based on the general population and explored whether variants associated with NAFLD also present associations with blood cell-related traits. Next, we applied systems biology approaches to assess the potential biological connection/s between genes that predispose affected individuals to NAFLD and nonalcoholic steatohepatitis, and genes that modulate hematological-related traits-specifically platelet count. We reasoned that this analysis would allow the identification of potential molecular mediators that link NAFLD with platelets. Genes associated with platelet count are most highly expressed in the liver, followed by the pancreas, heart, and muscle. Conversely, genes associated with NAFLD presented high expression levels in the brain, lung, spleen, and colon. Functional mapping, gene prioritization, and functional analysis of the most significant loci (P < 1 × 10-8) revealed that loci involved in the genetic modulation of platelet count presented significant enrichment in metabolic and energy balance pathways. In conclusion, variants in genes influencing NAFLD exhibit pleiotropic associations with hematologic traits, particularly platelet count. Likewise, significant enrichment of related genes with variants influencing platelet traits was noted in metabolic-related pathways. Hence, this approach yields novel mechanistic insights into NAFLD pathogenesis.Fil: Pirola, Carlos Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Salatino, Adrián Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Sookoian, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentin

The response to postnatal stress: Amino acids transporters and pkc activity

During postnatal development, the central nervous system (CNS) is highly sensitive to effects of drugs, stressors and environment. In this study, we evaluated the effect of acute cold stress on g-aminobutyric acid (GABA) and L-serine (L-Ser) transporters in vitro, using the uptake of [3H]GABA and [3H]L-Ser by synaptosomes-enriched fractions isolated from rat cerebral cortex during postnatal development. We found that the maximal velocity (Vmax) L-Ser uptake after stress session was increased in almost all ages studied, except at postnatal-days (PD) 5, whereas the values of Km (uptake affinity) decreased in all ages from 5 to 21 PD compared with the control group. The highest values of Vmax and Km were obtained at PD7. At the same time, in GABA uptake, the Km decreased although Vmax increased in all ages considered after cold stress during development. Finally, we investigated the mechanism by which cells regulate the substrate affinity of L-serine and GABA transporters. We demonstrated a significantly increase in PKC activity to PD5 from PD21. Pretreatment with PKC inhibitor: staurosporine (SP) led to a restoration of control uptake in several postnatal-days suggesting a relationship between amino acids uptake and PKC activation. These findings suggest that a single exposure to postnatal cold stress at different periods after birth modifies both GABA and L-Ser transporters and the related increase in PKC activity could be intracellular events that participate in neuronal plasticity by early-life stress, which could be relevant to function of transporters in the adult rat brain.Fil: Odeon, Maria Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Salatino, Adrián Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Rodríguez, Carla Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Scolari, Mariano José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Acosta, Gabriela Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; Argentin

Genetic variation in long noncoding RNAs and the risk of nonalcoholic fatty liver disease

The human transcriptome comprises a myriad of non protein-coding RNA species, including long noncoding RNAs (lncRNAs), which have a remarkable role in transcriptional and epigenetic regulation. We hypothesized that variants in lncRNAs influence the susceptibility to nonalcoholic fatty liver disease (NAFLD). Using next generation sequencing, we performed a survey of genetic variation associated with randomly selected lncRNA-genomic regions located within both experimentally validated and computationally predicted regulatory elements. We used a two-stage (exploratory, n = 96 and replication, n = 390) case-control approach that included well-characterized patients with NAFLD diagnosed by liver biopsy. We sequenced > 263 megabase pairs at quality score > Q17, in a total of 2,027,565 reads, including 170 lncRNA-genomic regions. In the sequencing analysis and the validated dataset, we found that the rs2829145 A/G located in a lncRNA (lnc-JAM2-6) was associated with NAFLD and the disease severity. Prediction of regulatory elements in lnc-JAM2-6 showed potential sequence-specific binding motifs of oncogenes MAFK and JUND, and the transcription factor CEBPB that is involved in inflammatory response. The A-allele was significantly associated with NAFLD as disease trait (p = 0.0081) and the disease severity (NASH-nonalcoholic steatohepatitis vs. controls: OR 2.36 [95% CI: 1.54-3.62], p = 0.000078). The A-allele carriers also have significantly higher body mass index and glucose-related traits compared with homozygous GG. Hence, our results suggest that variation in lncRNAs contributes to NAFLD severity, while pointing toward the complexity of the genetic component of NAFLD, which involves still unexplored regulatory regions of the genome.Fil: Sookoian, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Rohr, Cristian Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Salatino, Adrián Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Dopazo, Hernán Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Fernández Gianotti, Tomás. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Castaño, Gustavo Osvaldo. Gobierno de la Ciudad de Buenos Aires. Hospital "Dr. Abel Zubizarreta"; ArgentinaFil: Pirola, Carlos José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentin

Intrahepatic bacterial metataxonomic signature in non-alcoholic fatty liver disease

Objective: We aimed to characterise the liver tissue bacterial metataxonomic signature in two independent cohorts of patients with biopsy-proven non-alcoholic fatty liver disease (NAFLD) diagnosis, as differences in the host phenotypic features - from moderate to severe obesity - may be associated with significant changes in the microbial DNA profile. Design and methods: Liver tissue samples from 116 individuals, comprising of 47 NAFLD overweight or moderately obese patients, 50 NAFLD morbidly obese patients elected for bariatric surgery and 19 controls, were analysed using high-throughput 16S rRNA gene sequencing. Results: Liver bacterial DNA profile significantly differs between morbidly obese and non-morbidly obese patients with NAFLD. Bacteroidetes (p=1.8e-18) and Firmicutes (p=0.0044) were over-represented in morbidly obese patients and Proteobacteria (p=5.2e-10) - specifically Gammaproteobacteria and Alphaproteobacteria, and Deinococcus-Thermus (p=0.00012) - were over-represented in the non-morbidly obese cohort. Cohort-specific analysis of liver microbial DNA signatures shows patterns linked to obesity. The imbalance in Proteobacteria (Alpha or Gamma) among non-morbidly obese patients, and Peptostreptococcaceae, Verrucomicrobia, Actinobacteria and Gamma Proteobacteria DNA among morbidly obese patients was associated with histological severity. Decreased amounts of bacterial DNA from the Lachnospiraceae family were associated with more severe histological features. Proteobacteria DNA was consistently associated with lobular and portal inflammation scores. Microbial DNA composition corresponded to predicted functional differences. Conclusion: This is the first comprehensive study showing that the liver tissue of NAFLD patients contains a diverse repertoire of bacterial DNA (up to 2.5×104 read counts). The liver metataxonomic signature may explain differences in the NAFLD pathogenic mechanisms as well as physiological functions of the host.Fil: Sookoian, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Salatino, Adrián Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Castaño, Gustavo Osvaldo. Gobierno de la Ciudad de Buenos Aires. Hospital "Dr. Abel Zubizarreta"; ArgentinaFil: Landa, Maria Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Fijalkowky, Cinthia Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Garaycoechea, Martin Enrique. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic; ArgentinaFil: Pirola, Carlos José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentin