62 research outputs found

    Triiodothyronine is required for the stimulation of type II 5'-deiodinase mRNA in rat brown adipocytes

    Get PDF
    10 pages, 6 figures.Type II 5'-iodothyronine deiodinase (D2), produces triiodothyronine (T(3)) and is stimulated by cold exposure via norepinephrine (NE) release in brown adipose tissue. Cultured rat brown adipocytes require T(3) for the adrenergic stimulation of D2 activity. D2 mRNA expression in cultured brown adipocytes is undetectable with the use of basal conditions or NE without T(3). Full D2 expression is achieved using NE + T(3), especially after prolonged T(3) exposure. beta(3)-Adrenergic agonists mimic the NE action, whereas cAMP analogs do not. Prolonged exposure to T(3) alone increases D2 mRNA. High T(3) doses (500 nM) inhibit the adrenergic stimulation of D2 activity while increasing D2 mRNA. The effects obtained with NE + T(3) or T(3) alone are suppressed by actinomycin, but not by cycloheximide, which leads to accumulation of short D2 mRNA transcripts. Prolonged or short exposure to T(3) did not change D2 mRNA half-life, but T(3) seemed to elongate it. In conclusion, T(3) is an absolute requirement for the adrenergic stimulation of D2 mRNA in brown adipocytes. T(3) upregulates D2 mRNA, an effect that might involve stimulation of factors required for transcription or for stabilization of D2 mRNA.This work was supported by research grants PB 95–0097 from Dirección General de Investigación Científica y Técnica, FISS 94/0274 and 99/0813 from Fondo de Investigaciones Sanitarias (FIS), and CAM 08.6/0030/1998 from Comunidad de Madrid (CAM) (Spain). R. Martínez de Mena was supported by research grants FISS 94/0274 (predoctoral studies) and CAM 08.6/0030/1998 (as postdoctoral).Peer reviewe

    The T3 receptor β1 isoform regulates UCP1 and D2 deiodinase in rat brown adipocytes

    Get PDF
    Brown adipose tissue (BAT) thermogenesis increases when uncoupling protein-1 (UCP1) is activated adrenergically and requires T3. In humans, UCP1 activation in BAT seems involved in body weight maintenance. BAT type 2 deiodinase (D2) increases in response to adrenergic agents, producing the T3 required for UCP1 expression. T3 actions are mediated by thyroid hormone nuclear T3 receptors (TR), TRα and TRβ. Studies in mice suggest that TRβ is required for UCP1 induction, whereas TRα regulates body temperature and adrenergic sensitivity. In the present study, we compare the effects of T3 vs. specific TRβ1 and TRα1 agonists [GC-1 and CO23] on the adrenergic induction of UCP1 and D2 in cultured rat brown adipocytes. T3 and GC-1 produced similar increases on UCP1, whereas CO23 increased UCP1 only at high doses (50 nM). GC-1 at low doses (0.2-10 nM) was less potent than T3, increasing the adrenergic stimulation of D2 activity and mRNA. At higher doses, GC-1 further stimulated whereas T3 inhibited D2 activity but not D2 mRNA, suggesting posttranscriptional effects. CO23 had no effect on D2 activity but increased D2 mRNA. T3, GC-1, or CO23 by themselves did not increase UCP1 or D2 mRNA. High T3 doses shortened D2 half-life and increased D2 turnover via proteasome, whereas GC-1 did not change D2 stability. The α1- and α2-adrenergic D2 responses increased using high T 3 doses. In summary, T3 increases the adrenergic stimulation of UCP1 and D2 expression mostly via the TRβ1 isoform, and in brown adipocytes, D2 is protected from degradation by the action of T 3 on TRβ1. Copyright © 2010 by The Endocrine Society.This work was supported by Research Grants SAF2006/01319 and SAF2009-09364 from Plan Nacional (Ministerio de Educación y Ciencia and Ministerio de Ciencia e Innovación) and FMM2006 from Fundación Médica Madrileña (Spain) (toM.-J.O.). Centro de Investigación Biomédica en Red de Fisiopatologia de la Obesidad y Nutrición (CIBERObn) is an initiative of Instituto de Salud Carlos III, Spain.Peer Reviewe

    Cerebral cortex hyperthyroidism of newborn Mct8-deficient mice transiently suppressed by Lat2 inactivation

    Full text link
    Thyroid hormone entry into cells is facilitated by transmembrane transporters. Mutations of the specific thyroid hormone transporter, MCT8 (Monocarboxylate Transporter 8, SLC16A2) cause an X-linked syndrome of profound neurological impairment and altered thyroid function known as the Allan-Herndon-Dudley syndrome. MCT8 deficiency presumably results in failure of thyroid hormone to reach the neural target cells in adequate amounts to sustain normal brain development. However during the perinatal period the absence of Mct8 in mice induces a state of cerebral cortex hyperthyroidism, indicating increased brain access and/or retention of thyroid hormone. The contribution of other transporters to thyroid hormone metabolism and action, especially in the context of MCT8 deficiency is not clear. We have analyzed the role of the heterodimeric aminoacid transporter Lat2 (Slc7a8), in the presence or absence of Mct8, on thyroid hormone concentrations and on expression of thyroid hormone-dependent cerebral cortex genes. To this end we generated Lat2-/-, and Mct8-/yLat2-/- mice, to compare with wild type and Mct8-/y mice during postnatal development. As described previously the single Mct8 KO neonates had a transient increase of 3,5,3′-triiodothyronine concentration and expression of thyroid hormone target genes in the cerebral cortex. Strikingly the absence of Lat2 in the double Mct8Lat2 KO prevented the effect of Mct8 inactivation in newborns. The Lat2 effect was not observed from postnatal day 5 onwards. On postnatal day 21 the Mct8 KO displayed the typical pattern of thyroid hormone concentrations in plasma, decreased cortex 3,5,3′-triiodothyronine concentration and Hr expression, and concomitant Lat2 inactivation produced little to no modifications. As Lat2 is expressed in neurons and in the choroid plexus, the results support a role for Lat2 in the supply of thyroid hormone to the cerebral cortex during early postnatal development

    Protein Identification and Haplotype Description of Homozygote Mutation Causing Congenital Plasminogen Deficiency

    Get PDF
    Severe type I Plasminogen (PLG) deficiency was clinically diagnosed after hyaline-positive periodic acid Schiff material was detected in the histologic study of superior tarsal conjunctiva and vulvar pseudomembrane of the patient. Direct immunofluorescence also confirmed multiple deposits of fibrinogen in the dermis. Plasma plasminogen activity was calculated in a <5% value (reference values, 75% to 150%) and sequencing of the PLG gene evidenced the homozygous mutation in c.2377T/A (p.Tyr793Asn), confirming the molecular diagnosis of congenital deficiency of plasminogen type 1. Genotype-Phenotype correlation among family members evidenced the recessive hereditary pattern of clinical manifestations of chronic inflammatory disease of the mucous membranes due to PLG deficiency, but co-dominance effect to present a decreased plasma plasminogen activity (46%) among heterozygous asymptomatic individuals. SNPs/CNVs whole genome array hybridization analysis in the patient, detected long Loss of Heterozygosity regions (LOH) and demonstrated the consanguinity in the family. Proteomic analysis identified impaired secretion of mutant PLG tissue specific proteins, as definitive molecular etiopathogenesis of the type I PLG deficiency in the patient

    BIRC6 Is Associated with Vulnerability of Carotid Atherosclerotic Plaque

    Get PDF
    Carotid atherosclerotic plaque rupture can lead to cerebrovascular accident (CVA). By comparing RNA-Seq data from vascular smooth muscle cells (VSMC) extracted from carotid atheroma surgically excised from a group of asymptomatic and symptomatic subjects, we identified more than 700 genomic variants associated with symptomatology (p < 0.05). From these, twelve single nucleotide polymorphisms (SNPs) were selected for further validation. Comparing genotypes of a hospital-based cohort of asymptomatic with symptomatic patients, an exonic SNP in the BIRC6 (BRUCE/Apollon) gene, rs35286811, emerged as significantly associated with CVA symptomatology (p = 0.002; OR = 2.24). Moreover, BIRC6 mRNA levels were significantly higher in symptomatic than asymptomatic subjects upon measurement by qPCR in excised carotid atherosclerotic tissue (p < 0.0001), and significantly higher in carriers of the rs35286811 risk allele (p < 0.0001). rs35286811 is a proxy of a GWAS SNP reported to be associated with red cell distribution width (RDW); RDW was increased in symptomatic patients (p < 0.03), but was not influenced by the rs35286811 genotype in our cohort. BIRC6 is a negative regulator of both apoptosis and autophagy. This work introduces BIRC6 as a novel genetic risk factor for stroke, and identifies autophagy as a genetically regulated mechanism of carotid plaque vulnerability.This work was financially supported by grants from the Departments of Education (Ref. PIBA2018-67) and Health (Ref. RIS3-2019222038) of the Basque Government, Vitoria-Gasteiz, Spain; by the Spanish Neurovascular Network (INVICTUSplus) (Ref. RD16/0019/0007) funded by the Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación, Madrid, Spain; and by the research project grant (IKERIKTUS) funded by the RefbioII Trans-Pyrenean Cooperation Network for Biomedical Research financed by Horizon 2020. I.A. is supported by the Maratón EiTB 2017 for Funding of Research into Stroke, Bilbao, Spain (Ref. BIO18/IC/005); R.T.N. is the recipient of a fellowship from the Secretaría Nacional de Ciencia y Tecnología e Innovación (SENACYT; Convocatoria Doctorado de Investigación Ronda III, 2018; Ref. BIDP-III-2018-12) of the Gobierno Nacional, República de Panamá

    NEWSHUB: Incubadora de contenidos formativos para la comunicación profesional de los resultados del Aprendizaje Basado en Proyectos (ABP)

    Get PDF
    El proyecto NEWSHUB pretende ser el punto de unión entre docentes y estudiantes a través de las asignaturas y proyectos que desarrollen ambos colectivos de la comunidad universitaria. En esta relación al mismo nivel entre profesor/alumno se proporciona apoyo, formación y asesoramiento para poder realizar proyectos de diversa índole y materializarlos para su uso y difusión tanto dentro del aula y el ámbito académico como fuera de ella en el terreno profesional. NEWSHUB es una incubadora de proyectos. Rediseñamos actividades y prácticas de clase para que se ajusten a una aplicación eficaz de la metodología de aprendizaje basado en proyectos. Ofrecemos asesoría y acompañamiento a docentes y estudiantes para que desarrollen su actividad académica integrando estrategias y procesos de calidad propios del ámbito profesional. NEWSHUB es una plataforma de formación. Ponemos contenidos formativos sobre comunicación eficiente a disposición de la comunidad educativa e investigadora y del sector de la orientación laboral y el fomento del emprendimiento. Ofrecemos recursos educativos abiertos a través de una plataforma web modular, interoperable y accesible, que alberga contenidos digitales de producción propia y un banco de buenas prácticas. NEWSHUB conecta asignaturas, docentes y estudiantes para que los resultados de los distintos procesos de enseñanza-aprendizaje se optimicen para el cumplimiento de los objetivos clave del proyecto: aplicar eficazmente metodologías abiertas en el aula; alimentar el porfolio y el currículum en la búsqueda de empleo y el fomento del emprendimiento; y generar recursos educativos y modelos de buenas prácticas para formar en una comunicación eficiente

    NEWSHUB: Incubadora de contenidos formativos para la comunicación profesional de los resultados del Aprendizaje Basado en Proyectos (ABP)

    Get PDF
    NEWSHUB es un espacio de encuentro académico y profesional. Su principal función es cubrir necesidades específicas de formación tanto para el profesorado como para el alumnado en materia de comunicación. La finalidad es facilitar que se diseñen actividades de aprendizaje basado en proyectos orientadas a generar productos comunicativos de calidad profesional, que sirvan a un tiempo como herramienta eficiente de aprendizaje en el entorno académico además de recurso destacado en el porfolio del alumnado para la búsqueda de empleo o la formalización de proyectos emprendedores. NEWSHUB es una incubadora de proyectos. Rediseñamos actividades y prácticas de clase para que se ajusten a una aplicación eficaz de la metodología de aprendizaje basado en proyectos. Ofrecemos asesoría y acompañamiento a docentes y estudiantes para que desarrollen su actividad académica integrando estrategias y procesos de calidad propios del ámbito profesional. NEWSHUB es una plataforma de formación. Ponemos contenidos formativos sobre comunicación eficiente a disposición de la comunidad educativa e investigadora y del sector de la orientación laboral y el fomento del emprendimiento. Ofrecemos recursos educativos abiertos a través de una plataforma web modular, interoperable y accesible, que alberga contenidos digitales de producción propia y un banco de buenas prácticas. NEWSHUB es coaching digital. Con la nueva situación provocada por la pandemia tenemos que adaptar nuestra manera de enseñar y de aprender haciendo que el entorno virtual sea un espacio en el que tanto profesores como estudiantes se encuentren tan cómodos como en el aula. Para ello acompañaremos a los docentes en ese tránsito y contaremos con la opinión directa de los alumnos/as que participan en nuestro proyecto. NEWSHUB conecta asignaturas, docentes y estudiantes para que los resultados de los distintos procesos de enseñanza-aprendizaje se optimicen para el cumplimiento de los objetivos clave del proyecto: aplicar eficazmente metodologías abiertas en el aula; alimentar el porfolio y el currículum en la búsqueda de empleo y el fomento del emprendimiento; y generar recursos educativos y modelos de buenas prácticas para formar en una comunicación eficiente. NEWSHUB también permite crear un puente entre profesores/as, alumnos/as y materias de otras facultades e incluso de otros países. La virtualización permite deslocalizar y ponernos en contacto para intercambiar experiencias, programas y recursos educativos proporcionando una visión más rica y abierta en diferentes contextos culturales y de diversidad. Como principal novedad, en esta segunda parte del proyecto, NEWSHUB se vuelve más internacional incorporando a profesores y profesoras de facultades de Comunicación y Diseño que imparten materiales similares. El objetivo de esta internacionalización es comparar el proceso de enseñanza y aprendizaje basada en proyectos en diferentes contextos culturales

    Risk Factors for COVID-19 in Inflammatory Bowel Disease: A National, ENEIDA-Based Case–Control Study (COVID-19-EII)

    Full text link
    (1) Scant information is available concerning the characteristics that may favour the acquisition of COVID-19 in patients with inflammatory bowel disease (IBD). Therefore, the aim of this study was to assess these differences between infected and noninfected patients with IBD. (2) This nationwide case-control study evaluated patients with inflammatory bowel disease with COVID-19 (cases) and without COVID-19 (controls) during the period March-July 2020 included in the ENEIDA of GETECCU. (3) A total of 496 cases and 964 controls from 73 Spanish centres were included. No differences were found in the basal characteristics between cases and controls. Cases had higher comorbidity Charlson scores (24% vs. 19%; p = 0.02) and occupational risk (28% vs. 10.5%; p < 0.0001) more frequently than did controls. Lockdown was the only protective measure against COVID-19 (50% vs. 70%; p < 0.0001). No differences were found in the use of systemic steroids, immunosuppressants or biologics between cases and controls. Cases were more often treated with 5-aminosalicylates (42% vs. 34%; p = 0.003). Having a moderate Charlson score (OR: 2.7; 95%CI: 1.3-5.9), occupational risk (OR: 2.9; 95%CI: 1.8-4.4) and the use of 5-aminosalicylates (OR: 1.7; 95%CI: 1.2-2.5) were factors for COVID-19. The strict lockdown was the only protective factor (OR: 0.1; 95%CI: 0.09-0.2). (4) Comorbidities and occupational exposure are the most relevant factors for COVID-19 in patients with IBD. The risk of COVID-19 seems not to be increased by immunosuppressants or biologics, with a potential effect of 5-aminosalicylates, which should be investigated further and interpreted with caution

    Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

    Get PDF
    In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

    Get PDF
    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030
    corecore