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1.
Int J Mol Sci ; 25(13)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39000409

RESUMEN

Cardiac fibrosis is a severe outcome of Chagas disease (CD), caused by the protozoan Trypanosoma cruzi. Clinical evidence revealed a correlation between fibrosis levels with impaired cardiac performance in CD patients. Therefore, we sought to analyze the effect of inhibitors of TGF-ß (pirfenidone), p38-MAPK (losmapimod) and c-Jun (SP600125) on the modulation of collagen deposition in cardiac fibroblasts (CF) and in vivo models of T. cruzi chronic infection. Sirius Red/Fast Green dye was used to quantify both collagen expression and total protein amount, assessing cytotoxicity. The compounds were also used to treat C57/Bl6 mice chronically infected with T. cruzi, Brazil strain. We identified an anti-fibrotic effect in vitro for pirfenidone (TGF-ß inhibitor, IC50 114.3 µM), losmapimod (p38 inhibitor, IC50 17.6 µM) and SP600125 (c-Jun inhibitor, IC50 3.9 µM). This effect was independent of CF proliferation since these compounds do not affect T. cruzi-induced host cell multiplication as measured by BrdU incorporation. Assays of chronic infection of mice with T. cruzi have shown a reduction in heart collagen by pirfenidone. These results propose a novel approach to fibrosis therapy in CD, with the prospect of repurposing pirfenidone to prevent the onset of ECM accumulation in the hearts of the patients.


Asunto(s)
Cardiomiopatía Chagásica , Fibrosis , Ratones Endogámicos C57BL , Piridonas , Animales , Piridonas/farmacología , Piridonas/uso terapéutico , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/parasitología , Cardiomiopatía Chagásica/metabolismo , Cardiomiopatía Chagásica/patología , Ratones , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/parasitología , Miocardio/patología , Miocardio/metabolismo , Colágeno/metabolismo , Trypanosoma cruzi/efectos de los fármacos , Humanos , Enfermedad Crónica , Factor de Crecimiento Transformador beta/metabolismo , Modelos Animales de Enfermedad , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Masculino , Antracenos
2.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167264, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38806073

RESUMEN

Phenothiazines inhibit antioxidant enzymes in trypanosomatids. However, potential interferences with host cell antioxidant defenses are central concerns in using these drugs to treat Trypanosoma cruzi-induced infectious myocarditis. Thus, the interaction of thioridazine (TDZ) with T. cruzi and cardiomyocytes antioxidant enzymes, and its impact on cardiomyocytes and cardiac infection was investigated in vitro and in vivo. Cardiomyocytes and trypomastigotes in culture, and mice treated with TDZ and benznidazole (Bz, reference antiparasitic drug) were submitted to microstructural, biochemical and molecular analyses. TDZ was more cytotoxic and less selective against T. cruzi than Bz in vitro. TDZ-pretreated cardiomyocytes developed increased infection rate, reactive oxygen species (ROS) production, lipid and protein oxidation; similar catalase (CAT) and superoxide dismutase (SOD) activity, and reduced glutathione's (peroxidase - GPx, S-transferase - GST, and reductase - GR) activity than infected untreated cells. TDZ attenuated trypanothione reductase activity in T. cruzi, and protein antioxidant capacity in cardiomyocytes, making these cells more susceptible to H2O2-based oxidative challenge. In vivo, TDZ potentiated heart parasitism, total ROS production, myocarditis, lipid and protein oxidation; as well as reduced GPx, GR, and GST activities compared to untreated mice. Benznidazole decreased heart parasitism, total ROS production, heart inflammation, lipid and protein oxidation in T. cruzi-infected mice. Our findings indicate that TDZ simultaneously interact with enzymatic antioxidant targets in cardiomyocytes and T. cruzi, potentiating the infection by inducing antioxidant fragility and increasing cardiomyocytes and heart susceptibility to parasitism, inflammation and oxidative damage.


Asunto(s)
Antioxidantes , Cardiomiopatía Chagásica , Miocitos Cardíacos , Especies Reactivas de Oxígeno , Tioridazina , Trypanosoma cruzi , Animales , Miocitos Cardíacos/parasitología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Trypanosoma cruzi/efectos de los fármacos , Ratones , Antioxidantes/farmacología , Especies Reactivas de Oxígeno/metabolismo , Tioridazina/farmacología , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/parasitología , Cardiomiopatía Chagásica/metabolismo , Cardiomiopatía Chagásica/patología , Miocarditis/parasitología , Miocarditis/tratamiento farmacológico , Miocarditis/metabolismo , Miocarditis/patología , Nitroimidazoles/farmacología , Nitroimidazoles/uso terapéutico , Masculino , Tripanocidas/farmacología , Superóxido Dismutasa/metabolismo , Estrés Oxidativo/efectos de los fármacos , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/metabolismo , Enfermedad de Chagas/patología , Catalasa/metabolismo , Ratas , NADH NADPH Oxidorreductasas/metabolismo
5.
Exp Biol Med (Maywood) ; 248(22): 2062-2071, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38235691

RESUMEN

Chagas disease (CD), caused by the protozoan parasite Trypanosoma cruzi, is a neglected disease affecting around 6 million people. About 30% of CD patients develop chronic Chagas disease cardiomyopathy (CCC), an inflammatory cardiomyopathy that occurs decades after the initial infection, while most infected patients (60%) remain asymptomatic in the so-called indeterminate form (IF). Death results from heart failure or arrhythmia in a subset of CCC patients. Myocardial fibrosis, inflammation, and mitochondrial dysfunction are involved in the arrhythmia substrate and triggering events. Survival in CCC is worse than in other cardiomyopathies, which may be linked to a Th1-T cell rich myocarditis with abundant interferon (IFN)-γ and tumor necrosis factor (TNF)-α, selectively lower levels of mitochondrial energy metabolism enzymes in the heart, and reduced levels of high-energy phosphate, indicating poor adenosine triphosphate (ATP) production. IFN-γ and TNF-α signaling, which are constitutively upregulated in CD patients, negatively affect mitochondrial function in cardiomyocytes, recapitulating findings in CCC heart tissue. Genetic studies such as whole-exome sequencing (WES) in nuclear families with multiple CCC/IF cases has disclosed rare heterozygous pathogenic variants in mitochondrial and inflammatory genes segregating in CCC cases. In this minireview, we summarized studies showing how IFN-γ and TNF-α affect cell energy generation, mitochondrial health, and redox homeostasis in cardiomyocytes, in addition to human CD and mitochondria. We hypothesize that cytokine-induced mitochondrial dysfunction in genetically predisposed patients may be the underlying cause of CCC severity and we believe this mechanism may have a bearing on other inflammatory cardiomyopathies.


Asunto(s)
Cardiomiopatías , Cardiomiopatía Chagásica , Enfermedad de Chagas , Enfermedades Mitocondriales , Humanos , Factor de Necrosis Tumoral alfa/metabolismo , Cardiomiopatía Chagásica/genética , Cardiomiopatía Chagásica/metabolismo , Cardiomiopatía Chagásica/patología , Cardiomiopatías/etiología , Miocitos Cardíacos/metabolismo , Inflamación , Arritmias Cardíacas , Enfermedad Crónica
6.
Front Immunol ; 12: 755862, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34867992

RESUMEN

Infection by the protozoan Trypanosoma cruzi causes Chagas disease cardiomyopathy (CCC) and can lead to arrhythmia, heart failure and death. Chagas disease affects 8 million people worldwide, and chronic production of the cytokines IFN-γ and TNF-α by T cells together with mitochondrial dysfunction are important players for the poor prognosis of the disease. Mitochondria occupy 40% of the cardiomyocytes volume and produce 95% of cellular ATP that sustain the life-long cycles of heart contraction. As IFN-γ and TNF-α have been described to affect mitochondrial function, we hypothesized that IFN-γ and TNF-α are involved in the myocardial mitochondrial dysfunction observed in CCC patients. In this study, we quantified markers of mitochondrial dysfunction and nitro-oxidative stress in CCC heart tissue and in IFN-γ/TNF-α-stimulated AC-16 human cardiomyocytes. We found that CCC myocardium displayed increased levels of nitro-oxidative stress and reduced mitochondrial DNA as compared with myocardial tissue from patients with dilated cardiomyopathy (DCM). IFN-γ/TNF-α treatment of AC-16 cardiomyocytes induced increased nitro-oxidative stress and decreased the mitochondrial membrane potential (ΔΨm). We found that the STAT1/NF-κB/NOS2 axis is involved in the IFN-γ/TNF-α-induced decrease of ΔΨm in AC-16 cardiomyocytes. Furthermore, treatment with mitochondria-sparing agonists of AMPK, NRF2 and SIRT1 rescues ΔΨm in IFN-γ/TNF-α-stimulated cells. Proteomic and gene expression analyses revealed that IFN-γ/TNF-α-treated cells corroborate mitochondrial dysfunction, transmembrane potential of mitochondria, altered fatty acid metabolism and cardiac necrosis/cell death. Functional assays conducted on Seahorse respirometer showed that cytokine-stimulated cells display decreased glycolytic and mitochondrial ATP production, dependency of fatty acid oxidation as well as increased proton leak and non-mitochondrial oxygen consumption. Together, our results suggest that IFN-γ and TNF-α cause direct damage to cardiomyocytes' mitochondria by promoting oxidative and nitrosative stress and impairing energy production pathways. We hypothesize that treatment with agonists of AMPK, NRF2 and SIRT1 might be an approach to ameliorate the progression of Chagas disease cardiomyopathy.


Asunto(s)
Cardiomiopatía Chagásica/metabolismo , Interferón gamma/metabolismo , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Estrés Oxidativo/fisiología , Factor de Necrosis Tumoral alfa/metabolismo , Adolescente , Adulto , Anciano , Cardiomiopatía Chagásica/patología , Cardiomiopatía Chagásica/fisiopatología , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/patología , Miocitos Cardíacos/patología , Adulto Joven
7.
Front Immunol ; 12: 712034, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34804007

RESUMEN

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi, is a neglected tropical disease and a health problem in Latin America. Etiological treatment has limited effectiveness in chronic CD; thus, new therapeutic strategies are required. The practice of physical exercises has been widely advocated to improve the quality of life of CD patients. The most frequent clinical CD manifestation is the chronic indeterminate form (CIF), and the effect of physical exercises on disease progression remains unknown. Here, in a CIF model, we aimed to evaluate the effect of physical exercises on cardiac histological, parasitological, mitochondrial, and oxidative metabolism, electro and echocardiographic profiles, and immunological features. To establish a CIF model, BALB/c and C57BL/6 mice were infected with 100 and 500 trypomastigotes of the Y T. cruzi strain. At 120 days postinfection (dpi), all mouse groups showed normal PR and corrected QT intervals and QRS complexes. Compared to BALB/c mice, C57BL/6 mice showed a lower parasitemia peak, mortality rate, and less intense myocarditis. Thus, C57BL/6 mice infected with 500 parasites were used for subsequent analyses. At 120 dpi, a decrease in cardiac mitochondrial oxygen consumption and an increase in reactive oxygen species (ROS) were detected. When we increased the number of analyzed mice, a reduced heart rate and slightly prolonged corrected QT intervals were detected, at 120 and 150 dpi, which were then normalized at 180 dpi, thus characterizing the CIF. Y-infected mice were subjected to an exercise program on a treadmill for 4 weeks (from 150 to 180 dpi), five times per week in a 30-60-min daily training session. At 180 dpi, no alterations were detected in cardiac mitochondrial and oxidative metabolism, which were not affected by physical exercises, although ROS production increased. At 120 and 180 dpi, comparing infected and non-infected mice, no differences were observed in the levels of plasma cytokines, indicating that a crucial biomarker of the systemic inflammatory profile was absent and not affected by exercise. Compared with sedentary mice, trained Y-infected mice showed similar parasite loads and inflammatory cells but reduced cardiac fibrosis. Therefore, our data show that physical exercises promote beneficial changes that may prevent CD progression.


Asunto(s)
Cardiomiopatía Chagásica/prevención & control , Enfermedad de Chagas/parasitología , Parasitemia/prevención & control , Condicionamiento Físico Animal/fisiología , Trypanosoma cruzi , Animales , Cardiomiopatía Chagásica/patología , Enfermedad de Chagas/metabolismo , Enfermedad de Chagas/patología , Enfermedad Crónica , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Fibrosis , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Carga de Parásitos , Parasitemia/metabolismo , Parasitemia/patología , Especies Reactivas de Oxígeno/metabolismo
8.
PLoS Negl Trop Dis ; 15(7): e0009613, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34314435

RESUMEN

Chagas disease, caused by the parasite Trypanosoma cruzi, is considered endemic in more than 20 countries but lacks both an approved vaccine and limited treatment for its chronic stage. Chronic infection is most harmful to human health because of long-term parasitic infection of the heart. Here we show that immunization with a virus-like particle vaccine displaying a high density of the immunogenic α-Gal trisaccharide (Qß-αGal) induced several beneficial effects concerning acute and chronic T. cruzi infection in α1,3-galactosyltransferase knockout mice. Approximately 60% of these animals were protected from initial infection with high parasite loads. Vaccinated animals also produced high anti-αGal IgG antibody titers, improved IFN-γ and IL-12 cytokine production, and controlled parasitemia in the acute phase at 8 days post-infection (dpi) for the Y strain and 22 dpi for the Colombian strain. In the chronic stage of infection (36 and 190 dpi, respectively), all of the vaccinated group survived, showing significantly decreased heart inflammation and clearance of amastigote nests from the heart tissue.


Asunto(s)
Cardiomiopatía Chagásica/prevención & control , Corazón/parasitología , Vacunas Antiprotozoos/inmunología , Trypanosoma cruzi , Animales , Anticuerpos Antiprotozoarios/sangre , Cardiomiopatía Chagásica/parasitología , Cardiomiopatía Chagásica/patología , Citocinas/genética , Citocinas/metabolismo , Femenino , Regulación de la Expresión Génica/inmunología , Inmunoglobulina G/sangre , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Macrófagos Peritoneales/parasitología , Ratones , Ratones Endogámicos C57BL , Parasitemia , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
9.
PLoS Negl Trop Dis ; 15(6): e0009421, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34077437

RESUMEN

BACKGROUND: Chagas disease (CD) is a neglected disease that induces heart failure and arrhythmias in approximately 30% of patients during the chronic phase of the disease. Despite major efforts to understand the cellular pathophysiology of CD there are still relevant open questions to be addressed. In the present investigation we aimed to evaluate the contribution of the Na+/Ca2+ exchanger (NCX) in the electrical remodeling of isolated cardiomyocytes from an experimental murine model of chronic CD. METHODOLOGY/PRINCIPAL FINDINGS: Male C57BL/6 mice were infected with Colombian strain of Trypanosoma cruzi. Experiments were conducted in isolated left ventricular cardiomyocytes from mice 180-200 days post-infection and with age-matched controls. Whole-cell patch-clamp technique was used to measure cellular excitability and Real-time PCR for parasite detection. In current-clamp experiments, we found that action potential (AP) repolarization was prolonged in cardiomyocytes from chagasic mice paced at 0.2 and 1 Hz. After-depolarizations, both subthreshold and with spontaneous APs events, were more evident in the chronic phase of experimental CD. In voltage-clamp experiments, pause-induced spontaneous activity with the presence of diastolic transient inward current was enhanced in chagasic cardiomyocytes. AP waveform disturbances and diastolic transient inward current were largely attenuated in chagasic cardiomyocytes exposed to Ni2+ or SEA0400. CONCLUSIONS/SIGNIFICANCE: The present study is the first to describe NCX as a cellular arrhythmogenic substrate in chagasic cardiomyocytes. Our data suggest that NCX could be relevant to further understanding of arrhythmogenesis in the chronic phase of experimental CD and blocking NCX may be a new therapeutic strategy to treat arrhythmias in this condition.


Asunto(s)
Arritmias Cardíacas/patología , Cardiomiopatía Chagásica/patología , Potenciales de Acción , Compuestos de Anilina/farmacología , Animales , Calcio/metabolismo , Fenómenos Electrofisiológicos , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Miocitos Cardíacos/patología , Enfermedades Desatendidas , Níquel/farmacología , Técnicas de Placa-Clamp , Éteres Fenílicos/farmacología , Retículo Sarcoplasmático/metabolismo , Intercambiador de Sodio-Calcio/metabolismo
11.
Int J Mol Sci ; 22(7)2021 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-33804922

RESUMEN

Chagas disease, caused by the parasite Trypanosoma cruzi (T. cruzi), remains a serious public health problem for which there is no effective treatment in the chronic stage. Intense cardiac fibrosis and inflammation are hallmarks of chronic Chagas disease cardiomyopathy (CCC). Previously, we identified upregulation of circulating and cardiac miR-21, a pro-fibrotic microRNA (miRNA), in subjects with CCC. Here, we explored the potential role of miR-21 as a therapeutic target in a model of chronic Chagas disease. PCR array-based 88 microRNA screening was performed in heart samples obtained from C57Bl/6 mice chronically infected with T. cruzi and serum samples collected from CCC patients. MiR-21 was found upregulated in both human and mouse samples, which was corroborated by an in silico analysis of miRNA-mRNA target prediction. In vitro miR-21 functional assays (gain-and loss-of-function) were performed in cardiac fibroblasts, showing upregulation of miR-21 and collagen expression upon transforming growth factor beta 1 (TGFß1) and T. cruzi stimulation, while miR-21 blockage reduced collagen expression. Finally, treatment of T. cruzi-infected mice with locked nucleic acid (LNA)-anti-miR-21 inhibitor promoted a significant reduction in cardiac fibrosis. Our data suggest that miR-21 is a mediator involved in the pathogenesis of cardiac fibrosis and indicates the pharmacological silencing of miR-21 as a potential therapeutic approach for CCC.


Asunto(s)
Cardiomiopatía Chagásica/terapia , MicroARNs/genética , Tratamiento con ARN de Interferencia/métodos , Animales , Células Cultivadas , Cardiomiopatía Chagásica/genética , Cardiomiopatía Chagásica/metabolismo , Cardiomiopatía Chagásica/patología , Colágeno/genética , Colágeno/metabolismo , Fibrosis , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/metabolismo , Miocitos Cardíacos/metabolismo , Miofibroblastos/metabolismo , Regulación hacia Arriba
12.
Biochimie ; 186: 82-93, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33891967

RESUMEN

Matrix metalloproteinases (MMPs) not only play a relevant role in homeostatic processes but are also involved in several pathological mechanisms associated with infectious diseases. As their clinical relevance in Chagas disease has recently been highlighted, we studied the modulation of circulating MMPs by Trypanosoma cruzi infection. We found that virulent parasites from Discrete Typing Units (DTU) VI induced higher proMMP-2 and MMP-2 activity in blood, whereas both low (DTU I) and high virulence parasites induced a significant decrease in proMMP-9 plasma activity. Moreover, trans-sialidase, a relevant T. cruzi virulence factor, is involved in MMP-2 activity modulation both in vivo and in vitro. It removes α2,3-linked sialyl residues from cell surface glycoconjugates, which then triggers the PKC/MEK/ERK signaling pathway. Additionally, bacterial sialidases specific for this sialyl residue linkage displayed similar MMP modulation profiles and triggered the same signaling pathways. This novel pathogenic mechanism, dependent on sialic acid removal by the neuraminidase activity of trans-sialidase, can be exploited by different pathogens expressing sialidases with similar specificity. Thus, here we present a new pathogen strategy through the regulation of the MMP network.


Asunto(s)
Cardiomiopatía Chagásica/enzimología , Glicoproteínas/metabolismo , Sistema de Señalización de MAP Quinasas , Metaloproteinasa 2 de la Matriz/metabolismo , Neuraminidasa/metabolismo , Proteínas Protozoarias/metabolismo , Trypanosoma cruzi/enzimología , Animales , Cardiomiopatía Chagásica/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ácido N-Acetilneuramínico
13.
PLoS Negl Trop Dis ; 15(4): e0008964, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33826636

RESUMEN

Chronic Chagas cardiomyopathy (CCC) caused by a parasite Trypanosoma cruzi is a life-threatening disease in Latin America, for which there is no effective drug or vaccine. The pathogenesis of CCC is complex and multifactorial. Previously, we demonstrated T. cruzi infected mice lose a significant amount of fat tissue which correlates with progression of CCC. Based on this an investigation was undertaken during both acute and chronic T. cruzi infection utilizing the FAT-ATTAC murine model (that allows modulation of fat mass) to understand the consequences of the loss of adipocytes in the regulation of cardiac parasite load, parasite persistence, inflammation, mitochondrial stress, ER stress, survival, CCC progression and CCC severity. Mice were infected intraperitoneally with 5x104 and 103 trypomastigotes to generate acute and chronic Chagas models, respectively. Ablation of adipocytes was carried out in uninfected and infected mice by treatment with AP21087 for 10 days starting at 15DPI (acute infection) and at 65DPI (indeterminate infection). During acute infection, cardiac ultrasound imaging, histological, and biochemical analyses demonstrated that fat ablation increased cardiac parasite load, cardiac pathology and right ventricular dilation and decreased survival. During chronic indeterminate infection ablation of fat cells increased cardiac pathology and caused bi-ventricular dilation. These data demonstrate that dysfunctional adipose tissue not only affects cardiac metabolism but also the inflammatory status, morphology and physiology of the myocardium and increases the risk of progression and severity of CCC in murine Chagas disease.


Asunto(s)
Cardiomiopatía Chagásica/metabolismo , Miocarditis/metabolismo , Adipogénesis , Tejido Adiposo Blanco/metabolismo , Animales , Cardiomiopatía Chagásica/parasitología , Cardiomiopatía Chagásica/patología , LDL-Colesterol/sangre , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Metabolismo de los Lípidos , Masculino , Ratones , Ratones Endogámicos C3H , Miocarditis/parasitología , Miocarditis/patología , Miocardio/metabolismo , Miocardio/patología , Carga de Parásitos , Ultrasonografía Doppler
14.
Parasitol Int ; 83: 102345, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33857596

RESUMEN

Chagas disease, caused by Trypanosoma cruzi, is a major neglected tropical disease that occurs mainly as chronic infection and systemic infection. Currently, there is no suitable and effective drug to treat this parasitic disease. Administration of nutrients with immunomodulatory properties, such as arginine and nitric oxide radicals, may be helpful as antiparasitic therapy. In this study, we evaluated the effects of arginine supplementation during the acute phase of infection under the development of chronic Chagas' heart disease in Swiss mice inoculated with the Berenice-78 strain of T. cruzi. The effectiveness of arginine was determined by daily detection of the parasite in the blood and long-term serum levels of nitric oxide and tumor necrosis factor-alpha, in addition to evaluation of heart tissue damage. Arginine could flatten parasitemia and prevent elevation of tumor necrosis factor-alpha in T. cruzi-infected mice. Regarding chronic inflammatory myocardial derangements, similar findings were verified among T. cruzi-infected groups. Arginine promoted collagenogenesis in the heart muscle tissue of T. cruzi-infected arginine-supplemented group. These data show the paradoxical benefits of arginine in improving the outcome of Chagas chronic cardiomyopathy.


Asunto(s)
Arginina/metabolismo , Cardiomiopatía Chagásica/patología , Colágeno/fisiología , Corazón/parasitología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Alimentación Animal/análisis , Animales , Arginina/administración & dosificación , Arginina/farmacología , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/parasitología , Dieta , Suplementos Dietéticos/análisis , Corazón/efectos de los fármacos , Ratones , Tripanocidas/administración & dosificación , Tripanocidas/metabolismo
15.
J Leukoc Biol ; 109(1): 233-244, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32450615

RESUMEN

Chronic Chagas cardiomyopathy is the main infectious myocarditis worldwide. Almost 30% of Trypanosoma cruzi infected individuals develop slow and progressive myocarditis that leads to ventricular dilation and heart failure. Heart transplantation is an established, valuable therapeutic option for end-stage Chagas disease patients. Although the pathophysiology of Chagas disease has been addressed for decades by numerous groups, the cardiac immunologic mechanisms involved in the progression of clinical manifestation are still unknown. Growing evidence demonstrates that hypoxia-inducible factor (HIF)-1α plays indispensable roles in driving immune response by triggering the expression of CD73 purinergic ecto-enzyme. Purinergic system controls the duration and magnitude of purine signals directed to modulate immune cells through the conversion of extracellular ATP (microbicide/proinflammatory) to the immunoregulatory metabolite adenosine. In the present work, we described that infiltrating leukocytes within cardiac explants from patients with end-stage Chagas cardiomyopathy up-regulated HIF-1α and CD73 expression. Moreover, the number of HIF-1α+ and CD73+ leukocytes positively correlated with the myocarditis severity and the local parasite load. Furthermore, we demonstrated a direct relationship between tissue parasite persistence and the influx of immune cells to the infected hearts, which ultimately determine the severity of the myocarditis. These findings provide evidence that CD73-dependent regulatory pathways are locally triggered in the myocardium of patients with end-stage Chagas disease.


Asunto(s)
5'-Nucleotidasa/biosíntesis , Cardiomiopatía Chagásica/inmunología , Subunidad alfa del Factor 1 Inducible por Hipoxia/biosíntesis , Leucocitos/inmunología , Miocarditis/inmunología , Adulto , Cardiomiopatía Chagásica/complicaciones , Cardiomiopatía Chagásica/patología , Femenino , Proteínas Ligadas a GPI/biosíntesis , Humanos , Leucocitos/metabolismo , Masculino , Persona de Mediana Edad , Miocarditis/etiología , Miocarditis/patología , Miocardio/inmunología , Miocardio/patología
16.
J Vet Cardiol ; 33: 1-5, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33221699

RESUMEN

Idiopathic dilated cardiomyopathy (DCM) is a common acquired cardiac disease in large breed dogs with a high prevalence in Doberman pinschers. It is characterized histologically by attenuated wavy fibers and fatty infiltration with degeneration. The phenotypic appearance of DCM includes ventricular dilation with systolic dysfunction and ventricular arrhythmias. These changes can be caused by other etiologies, including infectious, toxic, metabolic, and nutritional deficiencies. Chagas disease is the result of an infection with the protozoal parasite, Trypanosoma cruzi, transmitted by an insect vector. Histopathology of the myocardium is characterized by inflammation, fibrosis, and pseudocysts containing T. cruzi amastigotes. Differentiating idiopathic DCM from infectious myocarditis can be challenging when the clinical presentation and diagnostic test results are similar in affected dogs. We present thoracic radiographs, echocardiography, and post-mortem histopathology images obtained from two Doberman pinschers with similar signalment, clinical presentation, and electrocardiographic and echocardiographic appearance but with different appearing radiographs and different etiologies for their heart disease, one with idiopathic DCM and one with myocarditis attributed to Chagas disease, to highlight the value of considering alternative etiologies for DCM to guide additional clinical evaluation and owner counseling.


Asunto(s)
Cardiomiopatía Dilatada/veterinaria , Cardiomiopatía Chagásica/veterinaria , Enfermedades de los Perros/etiología , Animales , Cardiomiopatía Dilatada/diagnóstico por imagen , Cardiomiopatía Dilatada/etiología , Cardiomiopatía Dilatada/patología , Cardiomiopatía Chagásica/diagnóstico por imagen , Cardiomiopatía Chagásica/patología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/patología , Perros , Ecocardiografía/veterinaria , Electrocardiografía/veterinaria , Masculino , Tórax/diagnóstico por imagen , Trypanosoma cruzi/aislamiento & purificación
17.
Parasitol Int ; 80: 102213, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33137501

RESUMEN

Host genetic factors have been proposed as determinants of the variable progression of Chagas disease (ChD). Two polymorphisms, H558R and A572D, of the voltage-gated sodium channel α-subunit SCN5A gene were studied in chagasic patients in order to determine their contribution to the susceptibility to the development and/or to the progression of the cardiovascular disease. A total of 104 patients were classified as seronegative or seropositive for Trypanosoma cruzi antibodies. Clinical evaluation, electrocardiograms (ECG) and echocardiograms (Echo) were performed to detect any conduction and/or structural alteration. Patients were classified into: G1: without ECG and/or Echo alterations, G2: with ECG alterations and G3: with ECG and Echo alterations. H558R and A572D polymorphisms were detected by PCR. Cardiac alterations were more frequent in G2 + G3 seropositive patients. For H558R polymorphism, the C allele was significantly increased in seropositive G2 + G3 patients (P = 0.049. OR = 2.08; 95% CI = 1.12-4.33). When comparing the disease cardiac progression (G2 vs G3), the genotypes from the H558R polymorphism were associated to more intense cardiac alterations (P = 0.018). For A572D polymorphism, no associations were found. The results suggest a possible involvement of SCN5A polymorphisms in the susceptibility to chronic ChD and the disease progression, contributing to the elucidation of the molecular mechanism underlying this complex myocardiopathy. In this regard, this is the first work that studies this gene in the context of chagasic cardiomyopathy.


Asunto(s)
Cardiomiopatía Chagásica/genética , Canal de Sodio Activado por Voltaje NAV1.5/genética , Polimorfismo Genético , Adulto , Anciano , Argentina , Cardiomiopatía Chagásica/patología , Femenino , Marcadores Genéticos/genética , Humanos , Masculino , Persona de Mediana Edad , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo
18.
Parasitol Int ; 80: 102210, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33148532

RESUMEN

Quantification of parasites in the context of Chagas disease is required to monitor the treatment with benznidazole, disease-associated cardiomyopathies and graft rejection after heart transplantation. As parasitological exams lack sensitivity, Real Time Polymerase Chain Reaction (rt-PCR) has emerged to evaluate the parasite load in blood samples and cardiac biopsies. However, despite its higher sensitivity, rt-PCR does not provide information on the location and distribution of amastigote nests within infected tissues, the characterization of inflammatory infiltrates or changes to tissue architecture. On the contrary, a sensitive immunohistochemistry technique (IHC) could fill these gaps. In the present study, a quantitative IHC exam was standardized and validated by testing adipose and cardiac tissues of experimentally infected mice containing variable parasite load levels of T. cruzi assessed by a sensitive Sybr Green rt-PCR with kDNA primers. Tissues were divided into four groups according to the parasite load: group A- 100 parasites/50 ng of DNA; group B -10 parasites; group C - around 1 parasite and group D - less than 1 parasite/50 ng/DNA. IHC was able to detect T. cruzi in the four groups, even in group D tissues containing fractions of a single parasite/50 ng of DNA sample according to rt-PCR. In conclusion, a highly sensitivity and reliable quantitative immunohistochemistry technique was developed and is proposed to estimate the percentage of T. cruzi-infected tissue area in chagasic patients presenting with cardiomyopathies, as a complementary test to rt-PCR.


Asunto(s)
Cardiomiopatía Chagásica/patología , Corazón/parasitología , Inmunohistoquímica/métodos , Miocardio/patología , Carga de Parásitos/métodos , Trypanosoma cruzi/aislamiento & purificación , Animales , Biopsia/instrumentación , Ratones , Carga de Parásitos/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Motriz (Online) ; 27: e1021017720, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1154902

RESUMEN

Abstract Aims: Patients with Chagas cardiomyopathy (ChC) could have a significant reduction in functional capacity (FC). This study aimed to report the effect of a 24-week combined physical exercise program on the FC of a patient with ChC. Methods: A woman, 44 years old, with positive serology for ChC in stage B2 has submitted the following assessments: i) Physical assessment: ii) Cardiopulmonary exercise test; iii) Test of 1-maximum Repetition, iv) Evaluation of cardiac autonomic modulation by heart rate variability (HRV). Results: The results obtained revealed a reduction in the anthropometric parameters and the SBP after training. Additionally, we observed an improvement in FC (aerobic and strength condiction) and cardiac autonomic modulation after 24 weeks of combined training. Conclusion: Our findings show that of a 24-week combined physical exercise program improved either FC or HRVof the patient with ChC.


Asunto(s)
Humanos , Femenino , Adulto , Cardiomiopatía Chagásica/patología , Capacidad Residual Funcional , Entrenamiento de Fuerza , Frecuencia Cardíaca
20.
PLoS Negl Trop Dis ; 14(12): e0008889, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33351798

RESUMEN

Chronic Chagas disease cardiomyopathy (CCC), an especially aggressive inflammatory dilated cardiomyopathy caused by lifelong infection with the protozoan Trypanosoma cruzi, is a major cause of cardiomyopathy in Latin America. Although chronic myocarditis may play a major pathogenetic role, little is known about the molecular mechanisms responsible for its severity. The aim of this study is to study the genes and microRNAs expression in tissues and their connections in regards to the pathobiological processes. To do so, we integrated for the first time global microRNA and mRNA expression profiling from myocardial tissue of CCC patients employing pathways and network analyses. We observed an enrichment in biological processes and pathways associated with the immune response and metabolism. IFNγ, TNF and NFkB were the top upstream regulators. The intersections between differentially expressed microRNAs and differentially expressed target mRNAs showed an enrichment in biological processes such as Inflammation, inflammation, Th1/IFN-γ-inducible genes, fibrosis, hypertrophy, and mitochondrial/oxidative stress/antioxidant response. MicroRNAs also played a role in the regulation of gene expression involved in the key cardiomyopathy-related processes fibrosis, hypertrophy, myocarditis and arrhythmia. Significantly, a discrete number of differentially expressed microRNAs targeted a high number of differentially expressed mRNAs (>20) in multiple processes. Our results suggest that miRNAs orchestrate expression of multiple genes in the major pathophysiological processes in CCC heart tissue. This may have a bearing on pathogenesis, biomarkers and therapy.


Asunto(s)
Cardiomiopatía Chagásica/metabolismo , Cardiomiopatía Chagásica/patología , Regulación de la Expresión Génica/fisiología , MicroARNs/metabolismo , Enfermedad Crónica , Genoma Humano , Humanos , MicroARNs/genética , Análisis de Componente Principal
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