Dataset Information

Evidence of reversible bradycardia and arrhythmias caused by immunogenic proteins secreted by T. cruzi in isolated rat hearts.

ABSTRACT:

Rationale

Chagas cardiomyopathy, caused by the protozoan Trypanosoma cruzi, is characterized by alterations in intracellular ion, heart failure and arrhythmias. Arrhythmias have been related to sudden death, even in asymptomatic patients, and their molecular mechanisms have not been fully elucidated.

Objective

The aim of this study is to demonstrate the effect of proteins secreted by T. cruzi on healthy, isolated beating rat heart model under a non-damage-inducing protocol.

Methods and results

We established a non-damage-inducing recirculation-reoxygenation model where ultrafiltrate fractions of conditioned medium control or conditioned infected medium were perfused at a standard flow rate and under partial oxygenation. Western blotting with chagasic patient serum was performed to determine the antigenicity of the conditioned infected medium fractions. We observed bradycardia, ventricular fibrillation and complete atrioventricular block in hearts during perfusion with >50 kDa conditioned infected culture medium. The preincubation of conditioned infected medium with chagasic serum abolished the bradycardia and arrhythmias. The proteins present in the conditioned infected culture medium of >50 kDa fractions were recognized by the chagasic patient sera associated with arrhythmias.

Conclusions

These results suggest that proteins secreted by T. cruzi are involved in Chagas disease arrhythmias and may be a potential biomarker in chagasic patients.

SUBMITTER: Rodriguez-Angulo HO

PROVIDER: S-EPMC4315581 | biostudies-literature | 2015 Feb

REPOSITORIES: biostudies-literature

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Publications

Evidence of reversible bradycardia and arrhythmias caused by immunogenic proteins secreted by T. cruzi in isolated rat hearts.

Rodríguez-Angulo Héctor O HO Toro-Mendoza Jhoan J Marques Juan A JA Concepción Juan L JL Bonfante-Cabarcas Rafael R Higuerey Yoliver Y Thomas Luz E LE Balzano-Nogueira Leandro L López José R JR Mijares Alfredo A

PLoS neglected tropical diseases 20150203 2

<h4>Rationale</h4>Chagas cardiomyopathy, caused by the protozoan Trypanosoma cruzi, is characterized by alterations in intracellular ion, heart failure and arrhythmias. Arrhythmias have been related to sudden death, even in asymptomatic patients, and their molecular mechanisms have not been fully elucidated.<h4>Objective</h4>The aim of this study is to demonstrate the effect of proteins secreted by T. cruzi on healthy, isolated beating rat heart model under a non-damage-inducing protocol.<h4>Met ...[more]

PMID: 25647069

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Dataset Information

Evidence of reversible bradycardia and arrhythmias caused by immunogenic proteins secreted by T. cruzi in isolated rat hearts.

Rationale

Objective

Methods and results

Conclusions

Publications

Evidence of reversible bradycardia and arrhythmias caused by immunogenic proteins secreted by T. cruzi in isolated rat hearts.

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