Image-guided percutaneous intralesional administration of mesenchymal stromal cells in subjects with chronic complete spinal cord injury: a pilot study.

BACKGROUND AIMS: The potential of cell therapies to improve neurological function in subjects with spinal cord injury (SCI) is currently under investigation. In this context, the choice of cell type, dose, route and administration regimen are key factors. Mesenchymal stromal cells (MSCs) can be easily obtained, expanded and are suitable for autologous transplantation. Here we conducted a pilot study that evaluated safety, feasibility and potential efficacy of intralesional MSCs transplantation performed through image-guided percutaneous injection, in subjects with chronic complete SCI. METHODS: Five subjects with chronic traumatic SCI (>6 months), at thoracic level, classified as American Spinal Cord Injury Association impairment scale (AIS) grade A, complete injury, were included. Somatosensory evoked potentials (SSEP), spinal magnetic resonance imaging (MRI) and urodynamics were assessed before and after treatment. Autologous MSCs were injected directly into the lesion site through percutaneous injection guided by computerized tomography (CT). RESULTS: Tomography-guided percutaneous cell transplantation was a safe procedure without adverse effects. All subjects displayed improvements in spinal cord independence measure (SCIM) scores and functional independence measure (FIM), mainly due to improvements in bowel movements and regularity. Three subjects showed improved sensitivity to tactile stimulation. Two subjects improved AIS grade to B, incomplete injury, although this was sustained in only one of them during the study follow-up. CONCLUSION: Autologous bone marrow MSC transplantation, performed through CT-guided percutaneous injection, was shown to be safe and feasible. Further studies are required to demonstrate efficacy of this therapeutic scheme.

Evaluation of Galectin-3 as a Novel Biomarker for Chagas Cardiomyopathy.

OBJECTIVES: Chagas cardiomyopathy has worse long-term outcomes than other cardiomyopathies. A biomarker strategy to refer subjects for noninvasive cardiac imaging may help in the early identification of cardiac damage in subjects with Chagas disease. Galectin-3 (Gal-3) is a mediator of cardiac fibrosis shown to be upregulated in animal models of decompensated heart failure. Here we assessed the correlation of Gal-3 with myocardial fibrosis in patients with Chagas disease. METHODS: This study comprised 61 subjects with Chagas disease. All subjects underwent clinical assessments, Doppler echocardiography and magnetic resonance imaging. Plasmatic Gal-3 was determined by ELISA. RESULTS: Delayed enhancement (DE) was identified in 37 of 61 subjects (64%). The total amount of myocardial fibrosis was 9.4% [interquartile interval (IQI): 2.4-18.4]. No differences were observed in Gal-3 concentration according to the presence or absence of myocardial fibrosis, with a median Gal-3 concentration of 11.7 ng/ml (IQI: 9.4-15) in subjects with DE versus 12.9 ng/ml (IQI: 9.2-14) in subjects without DE (p = 0.18). No correlation was found between myocardial fibrosis and Gal-3 concentration (r = 0.098; p = 0.47). CONCLUSIONS: There is no correlation between the degree of myocardial fibrosis and the concentration of Gal-3 in subjects with Chagas disease.

Efficacy and Safety of Granulocyte-Colony Stimulating Factor Therapy in Chagas Cardiomyopathy: A Phase II Double-Blind, Randomized, Placebo-Controlled Clinical Trial.

Aim: Previous studies showed that granulocyte-colony stimulating factor (G-CSF) improved heart function in a mice model of Chronic Chagas Cardiomyopathy (CCC). Herein, we report the interim results of the safety and efficacy of G-CSF therapy vs. placebo in adults with Chagas cardiomyopathy. Methods: Patients with CCC, New York Heart Association (NYHA) functional class II to IV and left ventricular ejection fraction (LVEF) 50% or below were included. A randomization list using blocks of 2 and 4 and an allocation rate of 1:1 was generated by R software which was stratified by functional class. Double blinding was done to both arms and assessors were masked to allocations. All patients received standard heart failure treatment for 2 months before 1:1 randomization to either the G-CSF (10 mcg/kg/day subcutaneously) or placebo group (1 mL of 0.9% saline subcutaneously). The primary endpoint was either maintenance or improvement of NYHA class from baseline to 6-12 months after treatment, and intention-to-treat analysis was used. Results: We screened 535 patients with CCC in Salvador, Brazil, of whom 37 were randomized. Overall, baseline characteristics were well-balanced between groups. Most patients had NYHA class II heart failure (86.4%); low mean LVEF was 32 ± 7% in the G-CSF group and 33 ± 10% in the placebo group. Frequency of primary endpoint was 78% (95% CI 0.60-0.97) vs. 66% (95% CI 0.40-0.86), p = 0.47, at 6 months and 68% (95% CI 0.43-0.87) vs. 72% (95% CI 0.46-0.90), p = 0.80, at 12 months in placebo and G-CSF groups, respectively. G-CSF treatment was safe, without any related serious adverse events. There was no difference in mortality between both arms, with five deaths (18.5%) in treatment vs. four (12.5%) in the placebo arm. Exploratory analysis demonstrated that the maximum rate of oxygen consumption during exercise (VO2 max) showed an improving trend in the G-CSF group. Conclusion: G-CSF therapy was safe and well-tolerated in 12 months of follow-up. Although prevention of symptom progression could not be demonstrated in the present study, our results support further investigation of G-CSF therapy in Chagas cardiomyopathy patients. Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT02154269].

The Presence and Extension of Myocardial Fibrosis in the Undetermined Form of Chagas' Disease: A Study Using Magnetic Resonance.

BACKGROUND: Previous data has shown that patients in the indeterminate form of Chagas disease may present myocardial fibrosis as shown on through magnetic resonance imaging (MRI). However, there is little information available regarding the degree of severity of myocardial fibrosis in these individuals. This variable has the potential to predict the evolution of Chagas' disease into its cardiac form. OBJECTIVES: To describe the frequency and extent of myocardial fibrosis evaluated using an MRI in patients in the indeterminate form, and to compare it with other forms of the disease. METHODS: Patients were admitted one after another. Their clinical history was collected and they were submitted to laboratory exams and an MRI. RESULTS: Sixty-one patients with Chagas' disease, with an average age of 58 ± 9 years old, 17 patients in the indeterminate form, 16 in the cardiac form without left ventricular (LV) dysfunction and 28 in the cardiac form with LV dysfunction were studied. P <0.05 was considered to be statistically significant. Late enhancement was detected in 37 patients (64%). Myocardial fibrosis was identified in 6 individuals in indeterminate form (41%; 95% CI 23-66) in a proportion similar to that observed in cardiac form without LV dysfunction (44%); p = 1.0. Among the individuals with fibrosis, the total area of the affected myocardium was 4.1% (IIQ: 2.1 - 10.7) in the indeterminate form versus 2.3% (IIQ: 1-5) in the cardiac form without LV (p = 0.18). The left ventricular fraction ejection in subjects in the indeterminate form was similar to that of the individuals in the cardiac form without ventricular dysfunction (p = 0.09). CONCLUSION: The presence of fibrosis in the indeterminate form of Chagas' disease has a frequency and extension similar to that of in the cardiac form without dysfunction, suggesting that the former is part of a subclinical disease spectrum, rather than lacking cardiac involvement.

Lack of association between serum syndecan-4, myocardial fibrosis and ventricular dysfunction in subjects with chronic Chagas disease.

BACKGROUND: Syndecan-4 is a transmembrane glycoprotein associated with inflammation and fibrosis. Increased syndecan-4 levels were previously detected after acute myocardial infarction and in subjects with heart failure. However, the levels of syndecan-4 in subjects with Chagas disease have not so far been investigated. The aim of this study was to investigate the potential role of serum sydencan-4 as a novel biomarker for myocardial fibrosis and cardiac dysfunction in subjects with Chagas disease. METHODS: This study comprised subjects with Chagas disease (n = 56), being 14 (25%) with the indeterminate form, 16 (29%) with the cardiac form without ventricular dysfunction, and 26 (46%) with the cardiac form with ventricular dysfunction. RESULTS: Syndecan-4 serum concentrations did not correlate with presence or absence of myocardial fibrosis (P = 0.386) nor disease severity in subjects with Chagas disease (P = 0.918). Additionally, no correlation was found either between the degree of myocardial fibrosis and serum syndecan-4 [r = 0.08; P = 0.567] or between left ventricular ejection fraction and syndecan-4 [r = 0.02; P = 0.864]. In contrast, NT-proBNP levels correlated with ejection fraction and myocardial fibrosis. CONCLUSIONS: Our results demonstrate the lack of correlations between serum syndecan-4, myocardial fibrosis and cardiac dysfunction in subjects with Chagas disease. Further studies are required to show if syndecan-4 concentrations can be marker for prognosis assessment or disease progression.

Optimization of oncological ¹8F-FDG PET/CT imaging based on a multiparameter analysis.

PURPOSE: This paper describes a method to achieve consistent clinical image quality in (18)F-FDG scans accounting for patient habitus, dose regimen, image acquisition, and processing techniques. METHODS: Oncological PET/CT scan data for 58 subjects were evaluated retrospectively to derive analytical curves that predict image quality. Patient noise equivalent count rate and coefficient of variation (CV) were used as metrics in their analysis. Optimized acquisition protocols were identified and prospectively applied to 179 subjects. RESULTS: The adoption of different schemes for three body mass ranges (<60 kg, 60-90 kg, >90 kg) allows improved image quality with both point spread function and ordered-subsets expectation maximization-3D reconstruction methods. The application of this methodology showed that CV improved significantly (p < 0.0001) in clinical practice. CONCLUSIONS: Consistent oncological PET/CT image quality on a high-performance scanner was achieved from an analysis of the relations existing between dose regimen, patient habitus, acquisition, and processing techniques. The proposed methodology may be used by PET/CT centers to develop protocols to standardize PET/CT imaging procedures and achieve better patient management and cost-effective operations.

Assessment of Galectin-3 Polymorphism in Subjects with Chronic Chagas Disease.

BACKGROUND: Galectin-3, a ß-galactoside binding lectin, has been described as a mediator of cardiac fibrosis in experimental studies and as a risk factor associated with cardiovascular events in subjects with heart failure. Previous studies have evaluated the genetic susceptibility to Chagas disease in humans, including the polymorphisms of cytokine genes, demonstrating correlations between the genetic polymorphism and cardiomyopathy development in the chronic phase. However, the relationship between the galectin-3 single nucleotide polymorphism (SNP) and phenotypic variations in Chagas disease has not been evaluated. OBJECTIVE: The present study aimed to determine whether genetic polymorphisms of galectin-3 may predispose to the development of cardiac forms of Chagas disease. METHODS: Fifty-five subjects with Chagas disease were enrolled in this observational study. Real-time polymerase chain reaction (PCR) was used for genotyping the variants rs4644 and rs4652 of the galectin-3 gene. RESULTS: For the SNP rs4644, the relative risk for the cardiac form was not associated with the genotypes AA (OR = 0.79, p = 0.759), AC (OR = 4.38, p = 0.058), or CC (OR = 0.39, p = 0.127). Similarly, for the SNP rs4652, no association was found between the genotypes AA (OR = 0.64, p = 0.571), AC (OR = 2.85, p = 0.105), or CC (OR = 0.49, p = 0.227) and the cardiac form of the disease. CONCLUSION: Our results showed no association between the different genotypes for both SNPs of the galectin-3 gene and the cardiac form of Chagas disease.

Safety and neurological assessments after autologous transplantation of bone marrow mesenchymal stem cells in subjects with chronic spinal cord injury.

INTRODUCTION: The administration of stem cells holds promise as a potential therapy for spinal cord injury (SCI). Mesenchymal stem cells have advantages for clinical applications, since they can be easily obtained, are suitable for autologous transplantation and have been previously shown to induce regeneration of the spinal cord in experimental settings. Here we evaluated the feasibility, safety and potential efficacy of autologous transplantation of mesenchymal stem cells in subjects with chronic complete SCI. METHOD: We conducted a phase I, non-controlled study in 14 subjects of both genders aging between 18 to 65 years, with chronic traumatic SCI (>6 months), at thoracic or lumbar levels, classified as American Spinal Injury Association (ASIA) A - complete injury. Baseline somatosensory evoked potentials (SSEP), spinal magnetic resonance imaging (MRI) and urodynamics were assessed before and after treatment. Pain rating was performed using the McGill Pain Questionnaire and a visual analogue score scale. Bone marrow-derived mesenchymal stem cells were cultured and characterized by flow cytometry, cell differentiation assays and G-band karyotyping. Mesenchymal stem cells were injected directly into the lesion following laminectomy and durotomy. RESULTS: Cell transplantation was an overall safe and well-tolerated procedure. All subjects displayed variable improvements in tactile sensitivity and eight subjects developed lower limbs motor functional gains, principally in the hip flexors. Seven subjects presented sacral sparing and improved American Spinal Injury Association impairment scale (AIS) grades to B or C - incomplete injury. Nine subjects had improvements in urologic function. One subject presented changes in SSEP 3 and 6 months after mesenchymal stem cells transplantation. Statistically significant correlations between the improvements in neurological function and both injury size and level were found. CONCLUSION: Intralesional transplantation of autologous mesenchymal stem cells in subjects with chronic, complete spinal cord injury is safe, feasible, and may promote neurological improvements. TRIAL REGISTRATION: ClinicalTrials.gov NCT01325103 - Registered 28 March 2011.

Transplantation of adipose tissue mesenchymal stem cells in experimental chronic chagasic cardiopathy.

BACKGROUND: Chagas disease, caused by the protozoan Trypanosoma cruzi, is a major cause of heart failure in Latin America. Tissue therapy has been investigated as a possible therapeutic option for patients with cardiovascular disease. OBJECTIVE: This study evaluated the effects of therapy with mesenchymal stem cells in an experimental model of chronic Chagasic cardiomyopathy. METHODS: C57BL/6 mice were infected with 1000 trypomastigotes from the Colombian strain of T. cruzi and, after six months of infection, were treated with mesenchymal human stem cells from adipose tissue (STAT) or with Dulbecco/Vogt modified Eagle's minimal essential medium - DMEM (control). The treated group received two intraperitoneal injections of STAT (1x10(6) cells/dose), with a month interval between the two doses. Before and after the first and second months of treatment, the chagasic and normal control animals underwent cardiopulmonary exercise testing and electrocardiography. All animals were sacrificed under anesthesia after two months of treatment for histopathological analysis of the heart. RESULTS: No improvement was observed in arrhythmias and cardiovascular function in the group of animals treated with STAT; however, sections of mice hearts in this group revealed a significant reduction in the number of inflammatory cells (p<0.0001) and areas of fibrosis (p<0.01) in comparison with chagasic animals treated with DMEM. CONCLUSION: Thus, it is concluded that administration of intraperitoneal STAT can reduce inflammation and fibrosis in the heart of mice chronically infected with T. cruzi; however, there were no effects on the cardiac function two months after transplantation.

The Presence and Extension of Myocardial Fibrosis in the Undetermined Form of Chagas' Disease: A Study Using Magnetic Resonance / Presença e Extensão da Fibrose Miocárdica na Forma Indeterminada da Doença de Chagas: Estudo de Ressonância Magnética

Abstract Background: Previous data has shown that patients in the indeterminate form of Chagas disease may present myocardial fibrosis as shown on through magnetic resonance imaging (MRI). However, there is little information available regarding the degree of severity of myocardial fibrosis in these individuals. This variable has the potential to predict the evolution of Chagas' disease into its cardiac form. Objectives: To describe the frequency and extent of myocardial fibrosis evaluated using an MRI in patients in the indeterminate form, and to compare it with other forms of the disease. Methods: Patients were admitted one after another. Their clinical history was collected and they were submitted to laboratory exams and an MRI. Results: Sixty-one patients with Chagas' disease, with an average age of 58 ± 9 years old, 17 patients in the indeterminate form, 16 in the cardiac form without left ventricular (LV) dysfunction and 28 in the cardiac form with LV dysfunction were studied. P <0.05 was considered to be statistically significant. Late enhancement was detected in 37 patients (64%). Myocardial fibrosis was identified in 6 individuals in indeterminate form (41%; 95% CI 23-66) in a proportion similar to that observed in cardiac form without LV dysfunction (44%); p = 1.0. Among the individuals with fibrosis, the total area of the affected myocardium was 4.1% (IIQ: 2.1 - 10.7) in the indeterminate form versus 2.3% (IIQ: 1-5) in the cardiac form without LV (p = 0.18). The left ventricular fraction ejection in subjects in the indeterminate form was similar to that of the individuals in the cardiac form without ventricular dysfunction (p = 0.09). Conclusion: The presence of fibrosis in the indeterminate form of Chagas' disease has a frequency and extension similar to that of in the cardiac form without dysfunction, suggesting that the former is part of a subclinical disease spectrum, rather than lacking cardiac involvement.

Resumo Fundamento: Dados prévios têm demonstrado que pacientes na forma indeterminada podem apresentar fibrose miocárdica à ressonância magnética (RM). No entanto, são poucas as informações disponíveis quanto ao grau de fibrose miocárdica apresentada por esses indivíduos, o que guardaria relação com o potencial dessa variável na predição de evolução para a forma cardíaca da doença de Chagas. Objetivos: Descrever a frequência e extensão da fibrose miocárdica avaliada por RM em pacientes da forma indeterminada, comparando com as outras formas da doença. Métodos: Pacientes consecutivamente admitidos tiveram história clínica colhida e foram submetidos à realização de exames laboratoriais e RM. Resultados: Foram estudados 61 pacientes portadores da doença de Chagas, com média de idade de 58 ± 9 anos, sendo 17 pacientes na forma indeterminada, 16 na forma cardíaca sem disfunção do ventrículo esquerdo (VE) e 28 na forma com disfunção do VE. Foi considerado estatisticamente significante p < 0,05. Realce tardio foi detectado em 37 pacientes (64%). Foi identificada fibrose miocárdica em 6 indivíduos na forma indeterminada (41%; IC95% 23 - 66), proporção semelhante à observada na forma cardíaca sem disfunção do VE (44%); p = 1,0. Entre os indivíduos com fibrose, a área total do miocárdio acometida foi de 4,1% (IIQ: 2,1 - 10,7) na forma indeterminada versus 2,3% (IIQ: 1 - 5) na forma cardíaca sem disfunção do VE (p = 0,18). A fração de ejeção do ventrículo esquerdo nos indivíduos na forma indeterminada foi semelhante aos portadores da forma cardíaca sem disfunção ventricular (p = 0,09). Conclusão: A presença de fibrose na forma indeterminada da doença de Chagas tem frequência e extensão semelhante à forma cardíaca sem disfunção, o que sugere que a primeira faz parte de um espectro de doença subclínica, em vez da ausência de acometimento cardíaco.

Assessment of speckle tracking strain predictive value for myocardial fibrosis in subjects with Chagas disease.

BACKGROUND: One of the most challenging issues of chronic Chagas disease is to provide earlier detection of heart involvement. Two-dimensional speckle tracking (2-D ST) echocardiography, a new imaging modality with useful applications in several cardiac diseases, has been validated for subjects with myocardial infarction against cardiac magnetic resonance (CMR). Here we hypothesize that the longitudinal global strain (LGS) has an incremental value to ejection fraction for predicting myocardial fibrosis in subjects with Chagas disease. METHODS: This observational study comprised 58 subjects with Chagas disease, confirmed by two positive serologic tests. All subjects underwent conventional Doppler echocardiogram plus speckle tracking strain, and cardiac magnetic resonance. RESULTS: The ROC curve analysis revealed that both LGS (area under the curve: 0.78, p = 0.001) and ejection fraction (area under the curve: 0.82, p < 0.001) were significant predictors of myocardial fibrosis. Regarding the percentage of fibrosis, a high correlation was observed with both ejection fraction assessed by echocardiography (r = 0.70, p < 0.001) and LGS (r = 0.64, p < 0.001). However, when adjusted through multiple linear regression, the LGS lost statistical significance as a predictor of myocardial fibrosis (p = 0.111). CONCLUSIONS: LGS has no incremental value to conventional ejection fraction measurement in the prediction of myocardial fibrosis in subjects with Chagas disease.

Assessment of Galectin-3 Polymorphism in Subjects with Chronic Chagas Disease / Avaliação do Polimorfismo da Galectina-3 em Indivíduos com Doença de Chagas Crônica

AbstractBackground:Galectin-3, a β-galactoside binding lectin, has been described as a mediator of cardiac fibrosis in experimental studies and as a risk factor associated with cardiovascular events in subjects with heart failure. Previous studies have evaluated the genetic susceptibility to Chagas disease in humans, including the polymorphisms of cytokine genes, demonstrating correlations between the genetic polymorphism and cardiomyopathy development in the chronic phase. However, the relationship between the galectin-3 single nucleotide polymorphism (SNP) and phenotypic variations in Chagas disease has not been evaluated.Objective:The present study aimed to determine whether genetic polymorphisms of galectin-3 may predispose to the development of cardiac forms of Chagas disease.Methods:Fifty-five subjects with Chagas disease were enrolled in this observational study. Real-time polymerase chain reaction (PCR) was used for genotyping the variants rs4644 and rs4652 of the galectin-3 gene.Results:For the SNP rs4644, the relative risk for the cardiac form was not associated with the genotypes AA (OR = 0.79, p = 0.759), AC (OR = 4.38, p = 0.058), or CC (OR = 0.39, p = 0.127). Similarly, for the SNP rs4652, no association was found between the genotypes AA (OR = 0.64, p = 0.571), AC (OR = 2.85, p = 0.105), or CC (OR = 0.49, p = 0.227) and the cardiac form of the disease.Conclusion:Our results showed no association between the different genotypes for both SNPs of the galectin-3 gene and the cardiac form of Chagas disease. (Arq Bras Cardiol. 2015; [online].ahead print, PP.0-0).

ResumoFundamento:A galectina-3, uma lectina de ligação à β-galactosidase, foi descrita como um mediador de fibrose cardíaca em estudos experimentais e um fator de risco associado com eventos cardiovasculares em indivíduos com insuficiência cardíaca. Estudos prévios avaliaram a susceptibilidade genética para doença de Chagas em humanos, incluindo polimorfismos dos genes de citocinas, demonstrando correlações entre o polimorfismo genético e o desenvolvimento de cardiomiopatia na fase crônica. No entanto, a relação entre polimorfismos de nucleotídeo único (single nucleotide polymorphism, SNP) e variações fenotípicas na doença de Chagas ainda não foi avaliada.Objetivo:O presente estudo teve como objetivo determinar se os polimorfismos genéticos da galectina-3 podem predispor ao desenvolvimento de formas cardíacas da doença de Chagas.Métodos:Cinquenta e cinco indivíduos com doença de Chagas foram incluídos neste estudo observacional. A genotipagem das variantes rs4644 e rs4652 do gene da galectina-3 foi realizada por PCR (reação em cadeia de polimerase).Resultados:Para o SNP rs4644, não houve associação entre o risco relativo para a forma cardíaca e os genótipos AA (OR = 0,79, p = 0,759), AC (OR = 4,38, p = 0,058), ou CC (OR = 0,39, p = 0,127). Similarmente, para o SNP rs4652, não foi encontrada associação entre os genótipos AA (OR = 0,64, p = 0,571), AC (OR = 2,85, p = 0,105), ou CC (OR = 0,49, p = 0,227) e a forma cardíaca da doença.Conclusão:Nossos resultados não mostraram associação entre os diferentes genótipos para ambos SNPs do gene da galectina-3 e a forma cardíaca da doença de Chagas. (Arq Bras Cardiol. 2015; [online].ahead print, PP.0-0).

Transplante de células mesenquimais de tecido adiposo na cardiopatia chagásica crônica experimental / Transplantation of adipose tissue mesenchymal stem cells in experimental chronic chagasic cardiopathy

FUNDAMENTO: A doença de Chagas, causada pelo protozoário Trypanosoma cruzi, é uma das mais importantes causas de insuficiência cardíaca na América Latina. A terapia celular vem sendo investigada como uma possível opção terapêutica para pacientes com doenças cardiovasculares. OBJETIVO: O objetivo deste estudo foi avaliar os efeitos da terapia com células-tronco mesenquimais em um modelo experimental de cardiomiopatia chagásica crônica. MÉTODOS: Camundongos C57BL/6 foram infectados com 1000 tripomastigotas da cepa Colombiana de T. cruzi e, após seis meses de infecção, foram tratados com células-tronco mesenquimais derivadas de tecido adiposo humano (CTTAs) ou com meio DMEM (controle). O grupo tratado recebeu duas injeções intraperitoneais de CTTAs (1x106 células / dose), com um mês de intervalo entre as duas doses. Antes e após 1 e 2 meses de tratamento, os animais chagásicos e controles normais foram submetidos à eletrocardiograma e teste ergoespirométrico. Todos os animais foram sacrificados sob anestesia após 2 meses de tratamento, para análise histopatológica do coração. RESULTADOS: Não foi observada melhora de arritmias e da função cardiovascular no grupo tratado com CTTAs, porém secções de corações de camundongos deste grupo apresentaram uma redução significativa do número de células inflamatórias (p < 0,0001) e da área de fibrose (p < 0,01) em comparação com animais chagásicos tratados com DMEM. CONCLUSÃO: Deste modo, conclui-se que a administração de CTTAs por via intraperitoneal é capaz de reduzir inflamação e fibrose no coração de camundongos cronicamente infectados por T. cruzi, porém não teve efeitos na função cardíaca dois meses após o transplante.

BACKGROUND: Chagas disease, caused by the protozoan Trypanosoma cruzi, is a major cause of heart failure in Latin America. Tissue therapy has been investigated as a possible therapeutic option for patients with cardiovascular disease. OBJECTIVE: This study evaluated the effects of therapy with mesenchymal stem cells in an experimental model of chronic Chagasic cardiomyopathy. METHODS: C57BL/6 mice were infected with 1000 trypomastigotes from the Colombian strain of T. cruzi and, after six months of infection, were treated with mesenchymal human stem cells from adipose tissue (STAT) or with Dulbecco/Vogt modified Eagle's minimal essential medium - DMEM (control). The treated group received two intraperitoneal injections of STAT (1x10(6) cells/dose), with a month interval between the two doses. Before and after the first and second months of treatment, the chagasic and normal control animals underwent cardiopulmonary exercise testing and electrocardiography. All animals were sacrificed under anesthesia after two months of treatment for histopathological analysis of the heart. RESULTS: No improvement was observed in arrhythmias and cardiovascular function in the group of animals treated with STAT; however, sections of mice hearts in this group revealed a significant reduction in the number of inflammatory cells (p<0.0001) and areas of fibrosis (p<0.01) in comparison with chagasic animals treated with DMEM. CONCLUSION: Thus, it is concluded that administration of intraperitoneal STAT can reduce inflammation and fibrosis in the heart of mice chronically infected with T. cruzi; however, there were no effects on the cardiac function two months after transplantation.

Avaliação da expressão de syndecan-4 e de seu papel como biomarcador na cardiomiopatia chagásica crônica.

INTRODUÇÃO: A cardiomiopatia chagásica crônica (CCC), doença de elevada morbimortalidade, associada à grave disfunção ventricular e a arritmias cardíacas, caracteriza-se histologicamente por intensa reação inflamatória multifocal, com pronunciada fibrose miocárdica. Diante da ausência de uma terapia eficaz para os pacientes com as formas mais graves da doença, torna-se crucial a descoberta de biomarcadores que possam identificar pacientes em estágios mais precoces, sob risco mais elevado para a progressão da doença. Neste contexto, surge a syndecan-4, uma glicoproteína transmembrana associada à inflamação e fibrose, cujos níveis estão aumentados em indivíduos com insuficiência cardíaca. OBJETIVO: Neste trabalho, avaliamos o padrão de expressão da syndecan-4 no tecido cardíaco de camundongos e de indivíduos com cardiomiopatia chagásica e a possível correlação entre a concentração sérica de syndecan-4 com grau de fibrose miocárdica e com fração de ejeção do ventrículo esquerdo em indivíduos com doença de Chagas. MÉTODOS: A expressão de syndecan-4 foi avaliada através da contagem de vasos positivos para esta proteína no coração de camundongos em diferentes momentos após a infecção com a cepa colombiana de T. cruzi, e em fragmentos de corações explantados de indivíduos com doença de Chagas, cardiomiopatia isquêmica (CMI) e cardiomiopatia dilatada idiopática (CMDI). Também foram determinados nestes tecidos o número de células inflamatórias e o percentual de fibrose miocárdica. Na segunda etapa do trabalho, foi desenvolvido um estudo clínico, no qual foram incluídos 56 indivíduos com doença de Chagas, 8 controles saudáveis e 8 pacientes com insuficiência cardíaca não-chagásica. A concentração sérica de syndecan-4 foi determinada por ELISA. RESULTADOS: Evidenciamos expressão de syndecan-4 principalmente nas células musculares lisas, tanto em corações de camundongos quanto em fragmentos de corações humanos. Não foi encontrada correlação entre a expressão de syndecan-4 e inflamação ou fibrose nos corações de indivíduos com CCC. Também comparamos a expressão de syndecan-4 de indivíduos com CCC, CMDI e CMI. Não foram observadas diferenças no número de vasos positivos para syndecan-4/mm2 quando comparados os três grupos de indivíduos (P = 0,466), tendo sido observada uma diferença estatisticamente significativa no número de células inflamatórias/mm2 (P = 0,035). No estudo clínico, não foram observadas diferenças nas concentrações de syndecan-4 de acordo com a presença ou ausência de fibrose miocárdica (P=0,386) ou entre as três formas de apresentação da doença de Chagas (P = 0,918). Do mesmo modo, não houve correlação entre fibrose miocárdica e syndecan-4 (r = 0,08, P = 0,567) ou entre fração de ejeção do ventrículo esquerdo e syndecan-4 (r = 0,02; P = 0,864). CONCLUSÃO: Apesar de a syndecan-4 estar expressa nos corações tanto de camundongos quanto de seres humanos com doença de Chagas, os nossos dados sugerem que, em sua forma solúvel, esta proteína não possa ser utilizada como biomarcador ou como preditor de fibrose miocárdica para este perfil de pacientes.