Project description:Trypanosoma cruzi infection is a major cause of cardiomyopathy. Gene profiling studies of hearts from infected mice have revealed prominent changes in gene expression within many functional pathways. This variety of transcriptomic changes in infected mice raises the question of whether gene expression alterations in whole hearts are due to changes in infected cardiac myocytes or other cells or even to systemic effects of the infection on the heart. We employed microarrays to examine infected cardiac myocyte cultures 48 hr post-infection. Statistical comparison of gene expression levels of 2,258 well annotated unigenes in four independent cultures of infected and uninfected myocytes detected (p < 0.05) significant > 1.5 absolute fold changes in 221 (8.8%) of the sampled genes. Major categories of affected genes included those involved in immune response, extracellular matrix and cell adhesion. While changes in extracellular matrix and cell adhesion genes were anticipated, modulation of immune response genes in the infected myocytes was surprising. These findings on infected cardiac myocytes in culture reveal that altered gene expression described in the heart in Chagas disease are the consequence of both direct infection of the myocytes and resulting from presence of other cell types in the myocardium and systemic effects of infection. Transcriptomic alteration in neonatal mouse cultured cardiomyocytes induced by the parasite T.cruzi were detected by profiling and compared using AECOM mouse 32k oligonucleotide arrays hybridized in the "multiple yellow" strategy described in Iacobas et al, Biochem Biophys Res Commun. 2006 349(1):329-38.
Project description:Trypanosoma cruzi infection is a major cause of cardiomyopathy. Gene profiling studies of hearts from infected mice have revealed prominent changes in gene expression within many functional pathways. This variety of transcriptomic changes in infected mice raises the question of whether gene expression alterations in whole hearts are due to changes in infected cardiac myocytes or other cells or even to systemic effects of the infection on the heart. We employed microarrays to examine infected cardiac myocyte cultures 48 hr post-infection. Statistical comparison of gene expression levels of 2,258 well annotated unigenes in four independent cultures of infected and uninfected myocytes detected (p < 0.05) significant > 1.5 absolute fold changes in 221 (8.8%) of the sampled genes. Major categories of affected genes included those involved in immune response, extracellular matrix and cell adhesion. While changes in extracellular matrix and cell adhesion genes were anticipated, modulation of immune response genes in the infected myocytes was surprising. These findings on infected cardiac myocytes in culture reveal that altered gene expression described in the heart in Chagas disease are the consequence of both direct infection of the myocytes and resulting from presence of other cell types in the myocardium and systemic effects of infection.
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Keywords: wildtype vs Myc-null
Project description:An efficient innate immune recognition of the intracellular parasite T. cruzi is crucial for host protection against development of Chagas disease, which often leads to multiple organ damage, particularly the heart leading to cardiomyopathy. Mechanisms modulated by MyD88 have been shown to be necessary for resistance against T, cruzi infection. Recently, Nod-like receptors have been shown to play an important role as innate immune sensors, particularly as they relate to inflammasome function, caspase activation, and inflammatory cytokine production. In this study, we aimed to investigate the participation of innate immune responses in general, and inflammasomes in particular, in heart inflammation and cardiac damage upon infection with the T. cruzi parasite. We used microarrays to gain insight into gene expression in the cardiac tissue of mice infected with the causative agent of Trypanosoma cruzi, and identified distinct classes of up-regulated genes during this process, including important genes involved in inflammasome activation and innate immune responses in general.
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Hearts were taken from wide type and Myc-null Mouse embryos at E13.5 under the dissecting scope. Cardiac myocyte RNA was isolated using TRIZOL®Reagent Total RNA (100 ng) was hybridized to the Sentrix® MouseRef-8 Expression BeadChip that contains probes for ~24,000 transcripts. GeneChips were scanned using the Hewlett-Packard GeneArray Scanner G2500A. The data were analyzed with Illumina Inc. BeadStudio version 1.5.0.34 and normalized by rank invariant method.
Project description:An efficient innate immune recognition of the intracellular parasite T. cruzi is crucial for host protection against development of Chagas disease, which often leads to multiple organ damage, particularly the heart leading to cardiomyopathy. Mechanisms modulated by MyD88 have been shown to be necessary for resistance against T, cruzi infection. Recently, Nod-like receptors have been shown to play an important role as innate immune sensors, particularly as they relate to inflammasome function, caspase activation, and inflammatory cytokine production. In this study, we aimed to investigate the participation of innate immune responses in general, and inflammasomes in particular, in heart inflammation and cardiac damage upon infection with the T. cruzi parasite. We used microarrays to gain insight into gene expression in the cardiac tissue of mice infected with the causative agent of Trypanosoma cruzi, and identified distinct classes of up-regulated genes during this process, including important genes involved in inflammasome activation and innate immune responses in general. The hearts of C57BL/6 mice day 18 post-infection with a Y strain of the parasite T. cruzi, and uninfected controls were extraced for RNA extraction and hybridization on Affymetrix microarrays. We sought to compare gene expression among two groups of mice, and so extracted the hearts of 3 control uninfected mice, and of 3 infected mice 18 days post-infection.
Project description:Chronic chagasic cardiomyopathy is a leading cause of heart failure in Latin American countries. About 30% of Trypanosoma cruzi-infected individuals develop this severe symptomatic form of the disease, characterized by intense inflammatory response accompanied by fibrosis deposition in the heart. We performed a microarray analysis of a mouse model of this disease and identified >5% alterations of gene expression in the heart. Most of the upregulations were associated with immune-inflammatory responses (chemokines, adhesion molecules, cathepsins and MHC molecules) and fibrosis deposition (extracellular matrix components, lysyl oxidase and Timp1). Our results indicate potentially relevant factors involved in the pathogenesis of the disease that may provide new therapeutic targets in chronic Chagasâ disease. The heart transcriptomes of 4 age-mached Trypanosoma cruzi-infected and 4 control C57Bl/6 mice were profiled and compared using Duke Mouse 30k Oligonucleotide Arrays (Operon V3.0.1) hybridized in the "multiple yellow" strategy described in Iacobas et al, Biochem Biophys Res Commun. 2006 349(1):329-38.
Project description:Comparative genomic analysis of T. cruzi CLB vs Trypanosoma rangeli (strains SC, Choachí, C23, H14, R1625 and PIT10) and Trypanosoma conorhini