Chronic Chagasic Patients Research Articles

Metabolomic insights in advanced cardiomyopathy of chronic chagasic and idiopathic patients that underwent heart transplant

Heart failure (HF) studies typically focus on ischemic and idiopathic heart diseases. Chronic chagasic cardiomyopathy (CCC) is a progressive degenerative inflammatory condition highly prevalent in Latin America that leads to a disturbance of cardiac conduction system. Despite its clinical and epidemiological importance, CCC molecular pathogenesis is poorly understood. Here we characterize and discriminate the plasma metabolomic profile of 15 patients with advanced HF referred for heart transplantation – 8 patients with CCC and 7 with idiopathic dilated cardiomyopathy (IDC) – using gas chromatography/quadrupole time-of-flight mass spectrometry. Compared to the 12 heart donor individuals, also included to represent the control (CTRL) scenario, patients with advanced HF exhibited a metabolic imbalance with 21 discriminating metabolites, mostly indicative of accumulation of fatty acids, amino acids and important components of the tricarboxylic acid (TCA) cycle. CCC vs. IDC analyses revealed a metabolic disparity between conditions, with 12 CCC distinctive metabolites vs. 11 IDC representative metabolites. Disturbances were mainly related to amino acid metabolism profile. Although mitochondrial dysfunction and loss of metabolic flexibility may be a central mechanistic event in advanced HF, metabolic imbalance differs between CCC and IDC populations, possibly explaining the dissimilar clinical course of Chagas’ patients.

Exploring Peripheral Blood-Derived Extracellular Vesicles as Biomarkers: Implications for Chronic Chagas Disease with Viral Infection or Transplantation.

Extracellular vesicles (EVs) are lipid bilayer envelopes that encapsulate cell-specific cargo, rendering them promising biomarkers for diverse diseases. Chagas disease, caused by the parasite Trypanosoma cruzi, poses a significant global health burden, transcending its initial epicenter in Latin America to affect individuals in Europe, Asia, and North America. In this study, we aimed to characterize circulating EVs derived from patients with chronic Chagas disease (CCD) experiencing a reactivation of acute symptoms. Blood samples collected in EDTA were processed to isolate plasma and subsequently subjected to ultracentrifugation for particle isolation and purification. The EVs were characterized using a nanoparticle tracking analysis and enzyme-linked immunosorbent assay (ELISA). Our findings revealed distinctive differences in the size, concentration, and composition of EVs between immunosuppressed patients and those with CCD. Importantly, these EVs play a critical role in the pathophysiology of Chagas disease and demonstrate significant potential as biomarkers in the chronic phase of the disease. Overall, our findings support the potential utility of the CL-ELISA assay as a specific sensitive tool for detecting circulating EVs in chronic Chagasic patients, particularly those with recurrent infection following an immunosuppressive treatment or with concurrent HIV and Chagas disease. Further investigations are warranted to identify and validate the specific antigens or biomarkers responsible for the observed reactivity in these patient groups, which may have implications for diagnosis, the monitoring of treatment, and prognosis.

Abstract 11768: Regression of Inflammation by Cardiac Magnetic Resonance in Chronic Chagasic Patients Treated With Benznidazole

Introduction: Chagas disease (CD) is a neglected disease caused by Trypanosoma cruzi ( T. cruzi ), and benznidazole (BZN) is the most prescribed trypanocidal drug in Brazil in function of its best tolerability profile. While treatment with this drug is effective in acute disease, there is no consensus on its effectiveness in adults with chronic infection. Although it is now accepted that treatment directed against T. cruzi is necessary to avoid the long-term sequelae of the disease, the lack of reliable markers for assessment of treatment efficacy is a major obstacle to evaluating new drugs. Hypothesis: the objective of this study is to determine if BZN treatment reduces cardiac inflammation/fibrosis as assessed by magnetic resonance imaging (MRI), using parametric mapping techniques. Methods: Prospective, multi-center study of chronic CD patients underwent MRI T1 and T2 mapping and extracellular volume measurement (ECV) using the modified Look-Locker inversion recovery (MOLLI) sequence, undergoing treatment with BZN, at a dose of 300 mg/kg daily divided into two doses and taken for 60 days. Absolute change T1 and T2 mapping, ECV, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricle ejection fraction (LVEF) were analyzed from baseline to 6-month follow-up. Results: 53 patients (females 83%, 53.9 ± 11.9 years old) were studied. LVEDV (149 ± 27ml vs 147 ± 29ml, p = 0.52), LVESV (66 ± 29 vs 64 ± 15, p = 0.65) and LVEF (55 ± 11% vs 57 ± 8%, p = 0,28) did not change between baseline and post treatment. Native T1 time showed reduced values among anterior (1030 ± 41ms vs 1011 ± 52ms, p = 0.011), septal (1052 ± 53ms vs 1006 ± 38ms, p = 0.000) and lateral (1042 ± 55ms vs 1019 ± 44ms, p = 0.003) LV walls. T2 mapping showed reduction in LV septal wall (53 ± 4ms vs 52 ± 3ms, p = 0.005). ECV showed significant reduction from baseline to 6-month follow-up (29.9 ± 3,3% vs 28.2 ± 3.5%, p = 0.0001). Conclusions: For the first time, we observe favorable changes in CMR ECV, T1 and T2 mapping induced by benznidazole therapy in chronic Chagas disease patients. These findings suggest that there may be an opportunity to decrease fibrosis/inflammation in chronic CD patients with the use of this therapeutic approach.

Accessing the Variability of Multicopy Genes in Complex Genomes using Unassembled Next-Generation Sequencing Reads: The Case of Trypanosoma cruzi Multigene Families.

Repetitive elements cause assembly fragmentation in complex eukaryotic genomes, limiting the study of their variability. The genome of Trypanosoma cruzi, the parasite that causes Chagas disease, has a high repetitive content, including multigene families. Although many T. cruzi multigene families encode surface proteins that play pivotal roles in host-parasite interactions, their variability is currently underestimated, as their high repetitive content results in collapsed gene variants. To estimate sequence variability and copy number variation of multigene families, we developed a read-based approach that is independent of gene-specific read mapping and de novo assembly. This methodology was used to estimate the copy number and variability of MASP, TcMUC, and Trans-Sialidase (TS), the three largest T. cruzi multigene families, in 36 strains, including members of all six parasite discrete typing units (DTUs). We found that these three families present a specific pattern of variability and copy number among the distinct parasite DTUs. Inter-DTU hybrid strains presented a higher variability of these families, suggesting that maintaining a larger content of their members could be advantageous. In addition, in a chronic murine model and chronic Chagasic human patients, the immune response was focused on TS antigens, suggesting that targeting TS conserved sequences could be a potential avenue to improve diagnosis and vaccine design against Chagas disease. Finally, the proposed approach can be applied to study multicopy genes in any organism, opening new avenues to access sequence variability in complex genomes. IMPORTANCE Sequences that have several copies in a genome, such as multicopy-gene families, mobile elements, and microsatellites, are among the most challenging genomic segments to study. They are frequently underestimated in genome assemblies, hampering the correct assessment of these important players in genome evolution and adaptation. Here, we developed a new methodology to estimate variability and copy numbers of repetitive genomic regions and employed it to characterize the T. cruzi multigene families MASP, TcMUC, and transsialidase (TS), which are important virulence factors in this parasite. We showed that multigene families vary in sequence and content among the parasite's lineages, whereas hybrid strains have a higher sequence variability that could be advantageous to the parasite's survivability. By identifying conserved sequences within multigene families, we showed that the mammalian host immune response toward these multigene families is usually focused on the TS multigene family. These TS conserved and immunogenic peptides can be explored in future works as diagnostic targets or vaccine candidates for Chagas disease. Finally, this methodology can be easily applied to any organism of interest, which will aid in our understanding of complex genomic regions.

Genetic diversity of Trypanosoma cruzi strains isolated from chronic chagasic patients and non-human hosts in the state of São Paulo, Brazil.

Trypanosoma cruzi shows an exuberant genetic diversity. Currently, seven phylogenetic lineages, called discrete typing units (DTUs), are recognised: TcI-TcVI and Tcbat. Despite advances in studies on T. cruzi and its populations, there is no consensus regarding its heterogeneity. This study aimed to perform molecular characterisation of T. cruzi strains, isolated in the state of São Paulo, to identify the DTUs involved and evaluate their genetic diversity. T. cruzi strains were isolated from biological samples of chronic chagasic patients, marsupials and triatomines through culture techniques and subjected to molecular characterisation using the fluorescent fragment length barcoding (FFLB) technique. Subsequently, the results were correlated with complementary information to enable better discrimination between the identified DTUs. It was possible to identify TcI in two humans and two triatomines; TcII/VI in 19 humans, two marsupials and one triatomine; and TcIII in one human host, an individual that also presented a result for TcI, which indicated the possibility of a mixed infection. Regarding the strains characterised by the TcII/VI profile, the correlation with complementary information allowed to suggest that, in general, these parasite populations indeed correspond to the TcII genotype. The TcII/VI profile, associated with domestic cycles and patients with chronic Chagas disease, was the most prevalent among the identified DTUs. Furthermore, the correlation of the study results with complementary information made it possible to suggest that TcII is the predominant lineage of this work.

Enhanced Migratory Capacity of T Lymphocytes in Severe Chagasic Patients Is Correlated With VLA-4 and TNF-α Expression.

Trypanosoma cruzi infection in humans leads to progression to chronic chagasic myocarditis (CCM) in 30% of infected individuals, paralleling T cell inflammatory infiltrates in the heart tissue. T-cell trafficking into the hearts of CCM patients may be modulated by in situ expression of chemotactic or haptotactic molecules, as the chemokine CXCL12, the cytokine tumor necrosis factor-alpha (TNF-α), and extracellular matrix proteins (ECM), such as fibronectin. Herein we evaluated the expression of fibronectin, CXCL12, and TNF-α in the myocardial tissue of T. cruzi seropositive (asymptomatic or with CCM), as well as seronegative individuals as healthy controls. Hearts from CCM patients exhibited enhanced expression of these three molecules. CXCL12 and TNF-α serum levels were also increased in CCM individuals. We then evaluated T lymphocytes from chronic chagasic patients by cytofluorometry, in terms of membrane expression levels of molecules involved in cell activation and cell migration, respectively, HLA-DR and the VLA-4 (very late antigen-4, being one integrin-type fibronectin receptor). Indeed, the expression of HLA-DR and VLA-4 was enhanced on T lymphocytes from chagasic patients, especially in the CCM group. To further approach the dynamics of T cell migratory events, we performed fibronectin-, TNF-α-, and CXCL12-driven migration. Peripheral blood mononuclear cells (PBMCs) and T cells from CCM patients presented an ex vivo enhanced migratory capacity driven by fibronectin alone when this ECM protein was placed in the membrane of transwell migration chambers. When TNF-α was previously placed upon fibronectin, we observed a further and significant increase in the migratory response of both PBMCs and T lymphocytes. Overall, these data suggest the existence in patients with chronic Chagas disease of a cardiac inflammatory infiltrate vector that promotes the recruitment and accumulation of activated T cells, driven in part by enhanced tissue expression of fibronectin and TNF-α, as well as the respective corresponding VLA-4 and TNF receptors.

Relationship between left ventricular ejection fractions and electrocardiographic variations in chronic chagasic patients

The sistodiastolic dysfunction of the heart measured through global ejection of the left ventricle as systolic parameter and the ventricular rapid filling plus the time of ventricular total filling as parameters of function diastólica are informational facts of complementary examinations of high sensibility and specificity for this type of study. It was established a relationship between the fraction of left ventricular ejection global and segment, measured for ventriculografía radioisotópica of balance, with the disorders electrocardiográficos in chronic chagásic patients. It is possible to conclude that while major alteration exists in the fraction of ventricular ejection, major abnormal variations exist in the electrocardiography of the chronical chagasic patients. Those who presented complete block of right branch show the possible existence of association in the deterioration of the fraction of ejection apicoseptal, aspect that would allow to conclude that the complete blockade of right branch can be a variable predisposed. The statistical analysis of the fraction of ejection apical that was found shows that the decrease of this region has a statistical force with the electrocardiografic deterioration complete blockade of right branch more front left hemibloqueo, This scientific evidence is confirmed across the statistical and epidemiological evidence which indicators allow to observe a major prevalency in 66 % and a major association of 1.51 times of complete Blockade of Right Branch more front left hemibloqueo in relation to other segments.

EFFECTS OF CHAGASIC PATIENT'S SERA ON HUMAN INDUCED PLURIPOTENT STEM CELL-DERIVED CARDIOMYOCYTES

<h3>Background</h3> Chagas disease is an infectious disease caused by the protozoan Trypanosoma cruzi and can lead to cardiac dysfunction characterized by arrhythmias and heart failure. The presence of circulating autoantibodies capable of recognizing G-protein coupled receptors (GPCR) and activating β-adrenergic and muscarinic receptors has been proposed as an interactive and relevant pathophysiological factor in the development of the disease. However, the interaction of the sera from chronic chagasic patients with human cardiomyocytes has never been tested. This study investigated if chronic chagasic sera previously shown to activate β-adrenergic and muscarinic receptors in rodent and rabbit hearts could also activate these receptors in human cardiomyocytes. <h3>Methods</h3> An induced pluripotent stem cell (iPS) line derived from a healthy donor, previously generated, and characterized in our laboratory, was differentiated into cardiomyocytes (CM-iPS) and their electrophysiology was characterized by Multielectrode Array (MEA) system. We evaluated the effects of an anti-β-adrenergic (Aβ82) and an anti-muscarinic serum (M32) on spontaneous beat rate (BR), field potential amplitude (FPA), and field potential duration (FPD). To minimize the effect of BR on FPD, FPD was corrected (FPDc) using an adaptation of the Bazett equation (FPDc = FPD/√BP), where BP is the interval between spontaneous beats. During recordings, CM-iPS were continuously perfused with Tyrode solution containing or not chagasic sera from patients diluted at 1:100 (v:v). <h3>Results</h3> Sera Aβ-82 induced an increase in BR (16,90±4,22 bpm to 26,60±5,62 bpm, n=5, <i>p</i>=0.0177), FPD (164,03±6,18 ms to 208,73±9,44 ms, n=5, p<0.001), FPDc (80,18±3,16 ms to 139,29±5,90 ms, n=5, <i>p</i><0.001) and did not significantly alter the FPA in CM-iPS. When perfused in presence of atenolol 10µM, no changes in BR, FPD and FPA were observed. In contrast, perfusion of sera M32 decreased BR (46,33±2,46 bpm to 38,16±3,17bpm, n=4, p=0.0011), FPD (225,48±19,48 ms to 186,78±12,05 ms, n=4, <i>p</i>=0.0137), FPDc (179,61±9,66 ms to 131,72±6,14 ms n=4, <i>p</i><0.001) and FPA (675,64±58,61 µV to 458,25±54,09 µV, n=4, p=0,0009). When in presence of atropine 10µM, no changes in BR, FPD and FPA were observed. <h3>Conclusion</h3> We conclude that antibodies present in chronic chagasic patients‘ sera are capable of modulating GCPR activity in the human heart interacting with β-adrenergic and muscarinic receptors present in human cardiomyocytes.

Mixed infections by different Trypanosoma cruzi discrete typing units among Chagas disease patients in an endemic community in Panama.

BackgroundTrypanosoma cruzi, the hemoparasite that causes Chagas disease, is divided into six Discrete Typing Units or DTUs: TcI-TcVI plus Tcbat. This genetic diversity is based on ecobiological and clinical characteristics associated with particular populations of the parasite. The main objective of this study was the identification of DTUs in patients with chronic chagasic infections from a mountainous rural community in the eastern region of Panama.MethodsA total of 106 patients were tested for Chagas disease with three serological tests (ELISA, rapid test, and Western blot). Molecular diagnosis and DTU typing were carried out by conventional PCRs and qPCR targeting different genomic markers, respectively. As a control sample for the typing, 28 patients suspected to be chagasic from the metropolitan area of Panama City were included.ResultsResults showed a positivity in the evaluated patients of 42.3% (33/78); high compared to other endemic regions in the country. In the control group, 20/28 (71.43%) patients presented positive serology. The typing of samples from rural patients showed that 78.78% (26/33) corresponded to TcI, while 9.09% (3/33) were mixed infections (TcI plus TcII/V/VI). Seventy-five percent (15/20) of the patients in the control group presented TcI, and in five samples it was not possible to typify the T. cruzi genotype involved.ConclusionsThese results confirm that TcI is the main DTU of T. cruzi present in chronic chagasic patients from Panama. However, the circulation of other genotypes (TcII/V/VI) in this country is described for the first time. The eco-epidemiological characteristics that condition the circulation of TcII/V/VI, as well as the immune and clinical impact of mixed infections in this remote mountainous region should be investigated, which will help local action programs in the surveillance, prevention, and management of Chagas disease.

Effect of exercise training on cardiovascular autonomic and muscular function in subclinical Chagas cardiomyopathy: a randomized controlled trial.

Patients with chronic chagasic cardiomyopathy with preserved ventricular function present with autonomic imbalance. This study evaluated the effects of exercise training (ET) in restoring peripheral and cardiac autonomic control and skeletal muscle phenotype in patients with subclinical chronic chagasic cardiomyopathy. This controlled trial (NCT02295215) included 24 chronic chagasic cardiomyopathy patients who were randomized www.random.org/lists/ into two groups: those who underwent exercise training (n = 12) and those who continued their usual activities (n = 12). Eight patients completed the exercise training protocol, and 10 patients were clinically followed up for 4months. Muscular sympathetic nerve activity was measured by microneurography and muscle blood flow (MBF) using venous occlusion plethysmography. The low-frequency component of heart rate variability in normalized units (LFnuHR) reflects sympathetic activity in the heart, and the low-frequency component of systolic blood pressure variability in normalized units reflects sympathetic activity in the vessels. The infusion of vasoactive drugs (phenylephrine and sodium nitroprusside) was used to evaluate cardiac baroreflex sensitivity, and a vastus lateralis muscle biopsy was performed to evaluate atrogin-1 and MuRF-1 gene expression. The baroreflex sensitivity for increases (p = 0.002) and decreases (p = 0.02) in systolic blood pressure increased in the ET group. Muscle blood flow also increased only in the ET group (p = 0.004). Only the ET group had reduced resting muscular sympathetic nerve activity levels (p = 0.008) and sympathetic activity in the heart (LFnu; p = 0.004) and vessels (p = 0.04) after 4months. Regarding skeletal muscle, after 4months, participants in the exercise training group presented with lower atrogin-1 gene expression than participants who continued their activities as usual (p = 0.001). The reduction in muscular sympathetic nerve activity was positively associated with reduced atrogin-1 (r = 0.86; p = 0.02) and MuRF-1 gene expression (r = 0.64; p = 0.06); it was negatively associated with improved baroreflex sensitivity both for increases (r = -0.72; p = 0.020) and decreases (r = -0.82; p = 0.001) in blood pressure. ET improved cardiac and peripheral autonomic function in patients with subclinical chagasic cardiomyopathy. ET reduced MSNA and sympathetic activity in the heart and vessels and increased cardiac parasympathetic tone and baroreflex sensitivity. Regarding peripheral muscle, after 4months, patients who underwent exercise training had an increased cross-sectional area of type I fibers and oxidative metabolism of muscle fibers, and decreased atrogin-1 gene expression, compared to participants who continued their activities as usual. In addition, the reduction in MSNA was associated with improved cardiac baroreflex sensitivity, reduced sympathetic cardiovascular tone, and reduced atrogin-1 and MuRF-1 gene expression. ID: NCT02295215. Registered in June 2013.

CXCL9 and CXCL10 display an age-dependent profile in Chagas patients: a cohort study of aging in Bambui, Brazil

BackgroundChagas disease is endemic in Latin America and still represents an important public health problem in the region. Chronic cardiomyopathy is the most significant chronic form due to its association with morbidity and mortality. The last decade has seen increasing evidence that inflammatory cytokines and chemokines are responsible for the generation of inflammatory infiltrate and tissue damage, with chronic chagasic cardiomyopathy patients presenting a pro-inflammatory immune response. Although studies have evaluated the role of chemokines in experimental T. cruzi infection, few have addressed their systemic profile, especially for human infection and in aging populations. The present work aimed to use the data from a large population based study of older adults, conducted in an endemic area for Chagas disease, to examine the association between serum levels of cytokines and chemokines, T. cruzi infection and electrocardiogram (ECG) abnormality.MethodsThe present work evaluated serum levels of CCL2, CXCL9, CXCL10, CCL5, CXCL8, IL-1β, IL-6, TNF, IL-12 and IL-10 by Flow Cytometric Bead Array assay (CBA) and the results expressed in pg/ml. The baseline survey started in January 1st 1997, with 1284 participants of an aged population-based cohort. Participants signed an informed consent at baseline and at each subsequent visit and authorized death certificate and medical records verification.ResultsOur results demonstrated that Chagas disease patients had higher serum levels of CXCL9, CXCL10 and IL-1β and lower serum levels of CCL5 than non-infected subjects. Moreover, our data demonstrated that CXCL9 and CXCL10 increased in an age-dependent profile in Chagas disease patients.ConclusionTogether, this study provided evidences that serum biomarkers increase along the age continuum and may have potential implications for establishing clinical management protocols and therapeutic intervention in Chagas disease patients.

Effects of Chagasic patients' sera on human cardiomyocytes derived from iPS

Background & Aim Chagas disease is caused by the parasite Trypanosoma cruzi and can lead to cardiac dysfunction characterized by arrhythmias and heart failure. Antibodies present in chagasic patients' sera are known to recognize G-protein coupled receptors (GPCR) and have been shown to activate beta-adrenergic and muscarinic receptors in the hearts of rodents and rabbits. However, the interaction of the sera from chronic chagasic patients with human cardiomyocytes has never been tested. The aim of this work was to investigate if chronic chagasic sera previously shown to activate beta-adrenergic and muscarinic receptors in rodent and rabbit hearts could also activate these receptors in human cardiomyocytes. Methods, Results & Conclusion We generated an iPS cell line from a healthy young donor and differentiated it into cardiomyocytes. These iPS derived cardiomyocytes had their electrophysiology characterized by intracellular microelectrode recordings in Tyrode solution containing, or not, chagasic sera from patients diluted at 1:100 (v:v). Monolayers of iPS-derived cardiomyocytes were also used in MultiElectrodeArray (MEA) systems where spontaneous beat rate and field potential duration were evaluated. Results showed that sera previously shown to activate beta-adrenergic receptors in rabbit and rodent hearts, induced an increase in spontaneous beat rate and a shortening of action potential duration in human cardiomyocytes. In contrast, sera previously shown to activate muscarinic receptors in rodent and rabbit hearts decreased the spontaneous beat rate in human cardiomyocytes. We conclude that antibodies present in chronic patients' sera are capable of modulating GCPR activity in the human heart interacting with beta-adrenergic and muscarinic receptors present in human cardiomyocytes.

Chagas disease in Virgem da Lapa, Minas Gerais, Brazil: left ventricle aneurysm and the risk of death in the 24-year interval.

BACKGROUND Left ventricular aneurysm (LVA) is indicator of high morbidity in Chagas’ disease. A cross-sectional study performed identified LVA in 18.8% of the chronic chagasic patients (CCP).OBJECTIVE Determine the risk of death of patients with chronic chagasic cardiopathy (CCC) and LVA in 24-year interval.MATERIAL AND METHODS In 1995 a cohort of 298 CCP was evaluated by anamnesis, physical examination, EKG and ECHO and classified in groups: G0 = 86 without cardiopathy; G1 = 156 with cardiopathy without LVA and G2 = 56 with cardiopathy and LVA. 38 patients of G0 and G1 used benznidazole. Information about the deaths was obtained in the notary, death certificates, hospital records and family members.FINDINGS Were registered 113 deaths (37.9%): 107 (35.9%) attributed to cardiopathy and 6 (2.0%) to other causes (p < 0.05). Amongst these 107 deaths, 10 (11.6%) occurred in G0; 49 (31.4%) occurred in G1 and 48 (85.7%) occurred in G2 (p < 0.05). The risk of death was 2.7 and 7.4 times significantly higher in G2, than in G1 and G0, respectively.CONCLUSION Chronic chagasic patients with LVA and ejection fraction < 45% have a higher risk of death than those without.

Diminished Prolinemia in Chronic Chagasic Patients: A New Clue for Disease Pathology?

Trypanosoma cruzi, the etiological agent of Chagas disease, is dependent on proline for a variety of processes, such as energy metabolism, host cell invasion, differentiation, and resistance to osmotic, metabolic, and oxidative stress. On this basis, we investigated a possible relationship between prolinemia and severity of T. cruzi infection in chronic patients, as reported here. The study population consisted of 112 subjects, separated into 83 chronically T. cruzi-infected patients and 29 age-matched healthy volunteers (control) of both sexes, recruited at the Chagas Disease Service from the Department of Cardiology, Hospital Provincial del Centenario de Rosario (Rosario, Argentina). Chagasic patients were separated into three groups: chronic asymptomatic, mild/moderate, and severe chronic chagasic cardiomyopathy (CCC) subjects. We observed a significant decrease of 11.7% in prolinemia in chagasic patients when compared to controls. Further analysis within the three groups of chagasic patients also revealed a statistically significant decrease of prolinemia in severe CCC patients compared to controls, showing a relative difference of 13.6% in proline concentrations. These data point to the possibility that collagen—which participates in the healing process of cardiac tissue—and proline metabolism in the myocardium could constitute new factors affecting the evolution of Chagas disease.

TONGUE FUNCTION, SALIVARY FLOW RATE AND IgA, IgM AND IgG TOTAL SALIVARY LEVELS IN CHRONIC CHAGASIC PATIENTS

Although microscopic alterations have been detected in tongues and salivary glands of chagasic patients and the identification of biomarkers in saliva has proved advantageous, there are no studies evaluating tongue function and total salivary IgA, IgG and IgM levels in chronic chagasic patients. The aim of this study was to evaluate tongue function, salivary flow rate, and total salivary IgA, IgG and IgM levels comparing chronic and non-chronic chagasic individuals. 37 patients were selected: chronic cardiac chagasic patients (n=6), chronic chagasic patients with the associated form of the disease (cardiopathy and megaesophagus) (n=11), and nonchagasic individuals (n=20). The tongue function underwent a phonoaudiological evaluation.The salivary f low rate was measured by sialometry. The total salivary IgA, IgG and IgM levels were evaluated by sandwich ELISA assay. Chagasic patients with the associated form of the disease presented higher salivary flow rate and lower salivary protein levels. No significant differences were noted in the lingual function or in the total salivary immunoglobulin levels among the groups. Although patients with chagasic megaesophagus presented higher levels of salivary flow and lower salivary protein, the fact that there were no significant differencesin lingual function and total salivary immunoglobulin levels among the groups led to the conclusion that chronic chagas disease does not modify the lingual function or the total IgA, IgG and IgM salivary levels. The present study was the first to evaluate the function of the tongue and salivary total immunoglobulin levels in Chagas disease.

Intermediate Monocytes and Cytokine Production Associated With Severe Forms of Chagas Disease.

Monocytes are classified according to their CD14 and CD16 expression into classical (reparative), intermediate (inflammatory), and non-classical. This study assessed the frequency of monocyte and the relationship between monocyte subset percentages and the levels of blood cytokines in Colombian chagasic patients with different clinical forms. This study included chagasic patients in different clinical stages: indeterminate (IND) n = 14, chronic chagasic cardiomyopathy (CCC) n = 14, and heart transplant chagasic (HTCC) n = 9; controls with non-chagasic cardiopathy (NCC) n = 15, and healthy individuals (HI) n = 15. Peripheral blood mononuclear cells (PBMCs) were isolated, labeled for CD14, CD16, and HLA-DR, and analyzed by flow cytometry. Cytokines were measured with a bead-based immunoassay. Percentages of total CD14+ CD16+ and CD14+ HLA-DR+ monocytes were higher in patients with heart involvement (CCC, HTCC, and NCC) than controls. Percentages of intermediate monocytes increased in symptomatic chagasic patients (CCC and HTCC) compared to asymptomatic chagasic patients (IND) and controls (HI). Asymptomatic chagasic patients (IND) had higher percentages of classical monocytes, an increased production of CCL17 chemokine compared to chagasic symptomatic patients (CCC), and their levels of CCL17 was positively correlated with the percentage of classical monocyte subset. In CCC, the percentages of intermediate and classical monocytes were positively correlated with IL-6 levels, which were higher in this group compared to HI, and negatively with IL-12p40 concentration, respectively. Remarkably, there also was an important increased of classical monocytes frequency in three chronic chagasic patients who underwent cardiac transplant, of which one received anti-parasitic treatment. Our findings suggest that cardiac chagasic patients have an increased percentage of inflammatory monocytes and produce more IL-6, a biomarker of heart failure and left ventricular dysfunction, whereas asymptomatic chagasic individuals present a higher percentage of reparative monocytes and CCL17.

Monocytes subsets and cytokine levels in chronic Chagas disease

Abstract Monocytes are classified according to CD14 and CD16 expression into classical, intermediate and non classical. Variations in monocytes subsets are involved in the pathogenesis of protozoan and helminthic infections. This study assessed the relationship of monocyte subsets percentages and the level of cytokines in blood from Colombian chagasic patients. Donors included asymptomatic or indeterminate (IND), symptomatic or chronic cardiac chagasic (CCC) and heart transplant (HTCC) patients; also, non-chagasic cardiopathy patients (NCC) and healthy individuals (HI) as controls. Peripheral blood mononuclear cells (PBMCs) were isolated. Fc receptors were blocked using anti-CD16/CD32 and human AB serum. Cells were labeled with antibodies for CD14, CD16 and HLA-DR, and acquired in a flow cytometer. Cytokines were measured in plasma with a Human M1/M2 Macrophage kit. Comparisons were done with Kruskal-Wallis followed by Dunn’s post hoc test and correlations were evaluated by Spearman’s coefficient. Percentages of CD14+ CD16+ and CD14+ HLA-DR+ monocytes were higher in patients with heart involvement (CCC, HTCCC, and NCC). Percentage of intermediate monocytes (inflammatory) increased in CCC patients and was positively correlated with IL-6 concentration and negatively correlated with IL-12p40 levels. IND donors had higher percentages of classical monocytes and an increased production of CCL17, and they positively correlate. The results suggest that variations in the monocyte subsets and cytokines levels might be associated with protection (classical monocytes and CCL17) or the development (intermediate monocytes and IL-6) of chagasic myocardiopathy

Treatment of Chronic Chagasic Patients: Is Killing the Parasite the Only Option?

Chagas disease is a tropical illness characterised by arrhythmias, heart failure, and eventually death. In approximately 10–30% of patients, chronic disease appears 10–30 years after infection onset. One of the biggest challenges for treatment is how to manage disease progression during the non-symptomatic phase to avoid the most life-threatening consequences of Chagas disease. The aim of this review is to evaluate the empirical rationale for an alternative therapy based on pathophysiological mechanisms that lead to chronic cardiac pathology and that have the possibility of evaluation through serological markers. The author identifies L-arginine serum levels, IL-2, and short-form Cha autoantibodies as possible markers for Chagas disease and discusses the reports regarding the therapeutic potential of amiodarone and angiotensin-converting enzyme inhibitors to modulate the electrophysiological, inflammatory, and vascular disturbances that lead to symptomatic Chagas disease. This review considers this discussion to improve the comprehension of therapeutic alternatives based on the vast literature detailing Chagas disease’s pathophysiology.

Lower urinary tract dysfunction in chronic Chagas disease: clinical and urodynamic presentation

PurposeTo describe and give an estimation of the prevalence of urinary disorders in chronic Chagas disease, since most clinical research has been centered on the description of the cardiac and digestive forms.MethodsTo explore this topic, a cross-sectional study was conducted in 137 Bolivian adults of both sexes suffering from symptomatic chronic Chagas disease. All patients presenting confirmed chagasic cardiomyopathy, megacolon or both underwent a urologic symptom questionnaire, uroflowmetry, urinary tract ultrasonography and a creatinine assay. When urinary abnormality was detected, a complete urodynamic study was proposed including cystometry, pressure-flow studies and urethral pressure profile.ResultsOut of all study patients, 35 (26%) had a Chagas cardiomyopathy, 81 (59%) a megacolon, and 21 (15%) a megacolon associated with cardiomyopathy. In all, 63% presented urinary disorders defined by IPSS > 7 and/or ICIQ SF > 1. Among them, 62% were incontinent, mainly by bladder overactivity, and 45% presented grade 2 or 3 renal insufficiency. Of 49 patients, the urodynamic study identified 34 patients with detrusor overactivity (69%), mostly in those with Chagas megacolon. Median bladder functional capacity, urethral closure pressure and bladder compliance had normal values. Moreover, 36% of these patients presented moderate hypocontractility, without significant post-void residual.ConclusionsThis study evidenced lower urinary tract dysfunction in a majority of chronic chagasic patients; those presenting megacolon were more likely to suffer from urinary incontinence. These results strongly suggest including routine urological clinical investigation in chronic Chagas patients, as urinary incontinence due to overactive bladder is frequently observed in this population.

An autopsy-based study of Trypanosoma cruzi persistence in organs of chronic chagasic patients and its relevance for transplantation.

Chagas' disease (CD) is caused by infection with the protozoan Trypanosoma cruzi. The disease can affect the heart and/or the gastrointestinal (GI) tract, but around 70% of infected individuals remain asymptomatic in the chronic form. Organ transplantation from T.cruzi-infected donors is often avoided because of the risk of disease transmission, previously reported after heart, kidney, or liver transplantation. We investigated by histology, immunohistochemistry, and polymerase chain reaction (PCR) the persistence of T.cruzi in samples of the heart, lung, liver, kidney, pancreas, adrenal gland, esophagus, and GI tract of 21 chronic chagasic patients. Parasite persistence was detected in 12/21 (57.1%) heart samples, mainly by PCR-based assays. T.cruzi parasites were detected by histology and immunohistochemistry in smooth muscle cells of the central vein from 1/21 (4.8%) adrenal gland samples. No samples of the lung, liver, kidney, pancreas, esophagus, or GI tract were found to have parasites by histology, immunohistochemistry, or PCR. We concluded that, aside from the heart, the other solid organs of T.cruzi-infected donors can be used for transplantation with a lot of caution. Such organs are not safe in the view of previous reports of CD transmission, but seem to present a low T.cruzi load compared to the heart.