Respuesta inmunoreguladora y su relación con la inmunopatología cardiaca en la infección por Tryipanosoma cruzi

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 07-09-201

Cyclooxygenase-2 and prostaglandin E<inf>2</inf> signaling through prostaglandin receptor EP- 2 favor the development of myocarditis during acute trypanosoma cruzi infection

Inflammation plays an important role in the pathophysiology of Chagas disease, caused by Trypanosoma cruzi. Prostanoids are regulators of homeostasis and inflammation and are produced mainly by myeloid cells, being cyclooxygenases, COX-1 and COX-2, the key enzymes in their biosynthesis from arachidonic acid (AA). Here, we have investigated the expression of enzymes involved in AA metabolism during T. cruzi infection. Our results show an increase in the expression of several of these enzymes in acute T. cruzi infected heart. Interestingly, COX-2 was expressed by CD68+ myeloid heart-infiltrating cells. In addition, infiltrating myeloid CD11b+Ly6G- cells purified from infected heart tissue express COX-2 and produce prostaglandin E2 (PGE2) ex vivo. T. cruzi infections in COX-2 or PGE2- dependent prostaglandin receptor EP-2 deficient mice indicate that both, COX-2 and EP-2 signaling contribute significantly to the heart leukocyte infiltration and to the release of chemokines and inflammatory cytokines in the heart of T. cruzi infected mice. In conclusion, COX-2 plays a detrimental role in acute Chagas disease myocarditis and points to COX-2 as a potential target for immune intervention.This work was supported by (NG) grants from “Fondo de Investigaciones Sanitarias” (PS09/00538 and PI12/00289); “Universidad Autónoma de Madrid” and “Comunidad de Madrid” (CC08-UAM/SAL-4440/08); by (MF) grants from “Ministerio de Ciencia e Innovación” (SAF2010-17833); “Red de Investigación de Centros de Enfermedades Tropicales” (RICET RD12/0018/0004); European Union (HEALTH-FE-2008-22303, ChagasEpiNet); AECID Cooperation with Argentine (A/025417/09 and A/031735/10), Comunidad de Madrid (S-2010/BMD- 2332) and “Fundación Ramón Areces”. NAG was recipient of a ISCIII Ph.D. fellowship financed by the Spanish “Ministerio de Sanidad”. CCM and HC were recipients of contracts from SAF2010-17833 and PI060388, respectively.Peer Reviewe

Desarrollo Psicomotor en Preescolares con Anemia Ferropenica

La anemia ferrop&eacute;nica es una patolog&iacute;a muy frecuente en la infancia, con alta prevalencia en pa&iacute;ses subdesarrollados. Se ha demostrado la relaci&oacute;n negativa entre la presencia de anemia ferropriva y el desarrollo neurol&oacute;gico en los ni&ntilde;os. El objetivo del presente estudio fue conocer el desarrollo psicomotor de los ni&ntilde;os en edad preescolar con anemia ferrop&eacute;nica. M&eacute;todos: se incluyeron 60 ni&ntilde;os con edades comprendidas entre 2 y 6 a&ntilde;os, alumnos del Preescolar Estatal San Carlos, Maracay, Estado Aragua, a los cuales se les practic&oacute; determinaci&oacute;n capilar de hemoglobina. En 30 de ellos la hemoglobina present&oacute; valores inferiores a 11 g/dL. La muestra de sangre permiti&oacute; determinar los valores hematim&eacute;tricos correspondientes a la hematolog&iacute;a completa de rutina y la concentraci&oacute;n de hierro s&eacute;rico. Resultados: 30 ni&ntilde;os presentaron anemia microc&iacute;tica con amplitud de distribuci&oacute;n eritrocitaria (RDW) elevada, y solo 4 de ellos mostraron concentraci&oacute;n de hierro s&eacute;rico bajo. De los 30 ni&ntilde;os an&eacute;micos, 17 eran de sexo masculino y 13 de sexo femenino. Estos 30 ni&ntilde;os fueron valorados con el Test de Denver para determinar el desarrollo psicomotor. Se encontr&oacute; que 63,3% de estos ni&ntilde;os obtuvo calificaci&oacute;n anormal en el Test de Denver, reflejado en la mayor&iacute;a de los casos en el &aacute;rea de lenguaje (63,3%); la actividad motora fina fue anormal en 43,3% de los ni&ntilde;os y normal en el resto de los ni&ntilde;os estudiados. Conclusiones:los resultados evidencian el efecto negativo del d&eacute;ficit de hierro en el &aacute;rea cognitiva de los ni&ntilde;os preescolares.AbstractPSICOMOTOR DEVELOPMENT IN PRESCHOOL CHILDREN WITH FERROPENIC ANEMIAIron deficiency anemia is a very common disease in childhood, with a high prevalence in developing countries. It has been shown a negative relationship between iron deficiency anemia and the neurological development of children. The objective of this study was to determine the psychomotor development of preschool children with iron deficiency anemia. Methods: We included 60 children aged 2 to 6 years old, from the Preschool institution San Carlos, Maracay, Aragua State, Venezuela. In these 60 children the capillary hemoglobin assay revealed that 30 of them had hemoglobin concentration below 11 g/dL. All preschool children underwent blood sampling to determine their hematimetric values and serum iron concentration. Results: It was found that 30 children had microcytic anemia with elevated RDW and only 4 of them showed low serum iron concentration. Children with microcitic anemia were 17 male and 13 female. These 30 children were evaluated with the Denver Test for psychomotor development screening and we found that an abnormal score was exhibited by 63.3% of them, mainly reflected in the language area (63.3%). Fine motor activity was abnormal in 43.3% and normal in 43.3% of anemic children. Conclusions: These results demonstrate a negative association between iron deficiency with cognitive deficit in preschool children

Influencia de variables ambientales sobre la presenciade Panstrongylus Geniculatus (Latreille, 1811) en domicilios del área metropolitana de Caracas, Venezuela

oai:ojs2.tesla.puertomaderoeditorial.com.ar:article/1Panstrongylus geniculatus (Latreille, 1811) (Reduviidae: Triatominae) is a hematophagous bug generally associated with the wild cycle of Trypanosoma cruzi Chagas, 1909, the etiological agent of Chagas disease. The incursions of this insect into homes located in urban and peri-urban areas cause alarm in the population and are becoming more and more frequent. As a contribution to the available knowledge on the biology and ecology of P. geniculatus as a species that transmits T. cruzi in this type of environment, the objective was to explore the influence of six environmental variables (altitude, monthly precipitation, relative humidity, average temperature , solar radiation and wind speed) on the distribution of specimens of this species captured in homes of 12 localities of the Metropolitan Area of ​​Caracas (AMC). The parasitological evaluation of the 39 insects examined showed that about 90% of them presented flagellate forms in their feces. The largest number of specimens came from collections in localities of the Miranda state (n = 32), with reports being more common during the months of May and June. Principal Component Analysis (PCA) applied to these data as an exploratory tool concentrates 60% of the variance in the first two principal components and suggests monthly precipitation (mm) and relative humidity (%) as possible environmental variables. explanations of the presence of this species in homes of the AMC.Panstrongylus geniculatus (Latreille, 1811) (Reduviidae: Triatominae) es un chinche hematófago asociado generalmente al ciclo silvestre del Trypanosoma cruzi Chagas, 1909, agente etiológico de la Enfermedad de Chagas. Las incursiones de este insecto en domicilios ubicados en zonas urbanas y periurbanas causan alarma en la población y se hacen cada vez más frecuentes. Como un aporte al conocimiento disponible sobre la biología y ecología de P. geniculatus como especie transmisora de T. cruzi en este tipo de ambientes, se propuso como objetivo explorar la influencia de seis variables ambientales (altitud, precipitación mensual, humedad relativa, temperatura media, radiación solar y velocidad del viento) sobre la distribución de especímenes de esta especie capturados en domicilios de 12 localidades del Área Metropolitana de Caracas (AMC). La evaluación parasitológica de los 39 insectos examinados mostró que cerca del 90% de ellos presentaron formas flageladas en sus heces. La mayor cantidad de ejemplares provinieron de colectas en localidades del estado Miranda (n = 32), siendo más comunes los reportes durante los meses de mayo y junio. El Análisis de Componentes Principales (ACP) aplicado a estos datos la data como herramienta exploratoria concentra en los primeros dos componentes principales un 60% de la varianza y sugiere a la precipitación mensual (mm) y la humedad relativa (%) como posibles variables ambientales explicativas de la presencia de esta especie en domicilios del AMC

Analysis of the Dynamics of Infiltrating CD4+ T Cell Subsets in the Heart during Experimental Trypanosoma cruzi Infection

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, affects several million people in Latin America. Myocarditis, observed during both the acute and chronic phases of the disease, is characterized by an inammatory mononuclear cell infiltrate that includes CD4+ T cells. It is known that Th1 cytokines help to control infection. The role that Treg and Th17 cells may play in disease outcome, however, has not been completely elucidated. We performed a comparative study of the dynamics of CD4+ T cell subsets after infection with the T. cruzi Y strain during both the acute and chronic phases of the disease using susceptible BALB/c and non-susceptible C57BL/6 mice infected with high or low parasite inocula. During the acute phase, infected C57BL/6 mice showed high levels of CD4+ T cell infiltration and expression of Th1 cytokines in the heart associated with the presence of Treg cells. In contrast, infected BALB/c mice had a high heart parasite burden, low heart CD4+ T cell infiltration and low levels of Th1 and inflammatory cytokines, but with an increased presence of Th17 cells. Moreover, an increase in the expression of IL-6 in susceptible mice was associated with lethality upon infection with a high parasite load. Chronically infected BALB/c mice continued to present higher parasite burdens than C57BL/6 mice and also higher levels of IFN-γ, TNF, IL-10 and TGF-β. Thus, the regulation of the Th1 response by Treg cells in the acute phase may play a protective role in non-susceptible mice irrespective of parasite numbers. On the other hand, Th17 cells may protect susceptible mice at low levels of infection, but could, in association with IL-6, be pathogenic at high parasite loads. © 2013 Sanoja et al.Ministerio de Ciencia y Tecnología’’ (SAF2007-61716; SAF2005-02220); ‘‘Fondo de Investigaciones Sanitarias’’ (PS09/00538); ‘‘Red Temática de Investigación en Enfermedades cardiovasculares’’ (RECAVA RD06/0014/1013); ‘‘Red de Investigación de Centros de Enfermedades Tropicales’’ (RICET RD06/0021/0016); European Union (HEALTH-FE-2008-22303, ChagasEpiNet); ‘‘Universidad Autónoma de Madrid’’ and ‘‘Comunidad de Madrid’’ (CC08-UAM/SAL-4440/08); AECID cooperation with Argentine (A/025417/09) and ‘‘Fundación Ramón Areces’Peer Reviewe

Infected C57BL/6 mice showed greater numbers of cardiac infiltrating CD4⁺ T cells and more inflammation than infected BALB/c mice.

<p>BALB/c mice were infected with high inoculum (open bar) or low inoculum (open dashed bar). C57BL/6 mice were infected with high inoculum (filled bar) or low inoculum (filled dashed bar). (<b>A</b>) Immunofluorescence staining of heart tissue sections from BALB/c and C57BL/6 mice infected with high inoculum with anti-CD4 antibody at 14 d.p.i. (magnification: 630×). (<b>B</b>) Quantitative RT-PCR of total heart tissue RNA from non-infected (NI) mice and mice infected with either high inoculum (top) or low inoculum (bottom) at 7, 12, 17 and 22 d.p.i., utilizing the <i>Cd4</i> probe. (<b>C</b>) as for “B” utilizing the <i>Ifng, Il1a</i> and <i>Tnf</i> probes. Data were normalized with respect to NI mice (Fold change: 1) and represent at least two independent experiments performed with 3 mice per experimental group. Statistically significant differences between infected and non-infected mice (0 d.p.i.) and between BALB/c and C57BL/6 mice under each treatment are shown: *<i>p</i><0.05,**<i>p</i><0.01 and ***<i>p</i><0.001.</p

Infected BALB/c mice show a greater parasite load and more inflammation during the chronic phase than infected C57BL/6 mice.

<p>BALB/c and C57BL/6 mice were infected with the low inoculum and sacrificed at 100 d.p.i. (<b>A</b>) Specific <i>T. cruzi</i> PCR with DNA from the hearts of non-infected (NI) and infected BALB/c mice at 100 d.p.i.; parasite DNA was used as a positive control (C+) and H₂O as a negative control (C-). (<b>B</b>) As for “A” but for C57BL/6 mice. Quantitative RT-PCR from total heart tissue RNA of infected BALB/c mice (open dashed bars) and C57BL/6 mice (filled dashed bars) utilizing: (<b>C</b>) a <i>Cd4</i> probe, (<b>D</b>) <i>Ifng, Il1a, Tnf</i> and <i>Il2</i> probes, (<b>E</b>) <i>Il6</i> and <i>Il17a</i> probes and (<b>F</b>) <i>Foxp3</i>, <i>Fr4</i>, <i>Il10</i> and <i>Tgfb</i> probes. Data represent the results of at least two independent experiments performed with 3 mice per experimental group and were normalized with respect to NI mice (Fold change: 1). Statistically significant differences between infected and non-infected mice and between BALB/c and C57BL/6 mice under each treatment are shown: *<i>p</i><0.05,**<i>p</i><0.01 and ***<i>p</i><0.001.</p

BALB/c mice infected with <i>T. cruzi</i> showed higher parasite loads and lower survival rates than infected C57BL/6 mice.

<p>BALB/c mice were infected with high inoculum (open circle) or low inoculum (open square). C57BL/6 mice were infected with high inoculum (filled circle) or low inoculum (filled square). (<b>A</b>) Survival was monitored from 0 to 100 d.p.i., (<b>B</b>) parasitemia was monitored from 0 to 35 d.p.i., and (<b>C</b>) the parasite load in heart tissue was determined at 7, 12, 17 and 22 d.p.i. in mice infected with high inoculum (top) or low inoculum (bottom) by extrapolation with parasite DNA standards. Data represent the results of at least two independent experiments performed with 3 mice per experimental group. Statistically significant differences between BALB/c and C57BL/6 mice are shown: *<i>p</i><0.05, **<i>p</i><0.01 and ***<i>p</i><0.001.</p