Opportunities and challenges in chronic Chagas cardiomyopathy

Association between blood group antigens ABO, Rh, Kell, Kidd, Duffy and MNS and clinical forms of Chagas disease

BACKGROUND

The mechanisms that determine the progression to cardiac or digestive forms of chronic Chagas disease (CD) are still unclear. We assessed the association between blood group antigens ABO, Rh, Kell, Kidd, Duffy and MNS, and chronic CD clinical forms.

METHODS

Patients were included consecutively between March 2013 and April 2016. Clinical and epidemiological data were obtained from electronic medical records and interviews. Classification of CD clinical forms followed the Brazilian Consensus on CD. The ID-Gel Card technology from Bio-Rad (Diamed/Bio-Rad Latin America, MG, Brazil) was used to analyze the blood group antigens.

RESULTS

A total of 619 adult patients (56.9% women, mean age 60±12 y) were included. Patients' clinical forms of CD were classified as follows: indeterminate 29.1%, cardiac 55.4%, digestive 5.5% and mixed 10.0%. Logistic regression analysis adjusted for age, comorbidities and time away from an endemic area revealed that the S+s- allele of the MNS blood type was associated with a lower odds of cardiac disease and that the B blood group type was associated with a higher odds of digestive disease. All other blood types did not have an association with CD clinical form.

CONCLUSIONS

Blood group systems ABO and MNS were associated with chronic CD clinical forms.

Chagas' cardiomyopathy and Lyme carditis: Lessons learned from two infectious diseases affecting the heart

Chagas' disease and Lyme disease are two endemic, vector-borne zoonotic infectious diseases that impact multiple organ systems, including the heart. Chagas' cardiomyopathy is a progressive process that can evolve into a dilated cardiomyopathy and heart failure several decades after the acute infection; in contrast, although early-disseminated Lyme carditis has been relatively well characterized, the sequelae of Lyme disease on the heart are less well-defined. A century of research on Chagas' cardiomyopathy has generated compelling data for pathophysiological models, evaluated the efficacy of therapy in large randomized controlled trials, and explored the social determinants of health impacting preventative measures. Recognizing the commonalities between Chagas' disease and Lyme disease, we speculate on whether some of the lessons learned from Chagas' cardiomyopathy may be applicable to Lyme carditis.

High fat diet aggravates cardiomyopathy in murine chronic Chagas disease

Infection with Trypanosoma cruzi, the etiologic agent in Chagas disease, may result in heart disease. Over the last decades, Chagas disease endemic areas in Latin America have seen a dietary transition from the traditional regional diet to a Western style, fat rich diet. Previously, we demonstrated that during acute infection high fat diet (HFD) protects mice from the consequences of infection-induced myocardial damage through effects on adipogenesis in adipose tissue and reduced cardiac lipidopathy. However, the effect of HFD on the subsequent stages of infection - the indeterminate and chronic stages - has not been investigated. To address this gap in knowledge, we studied the effect of HFD during indeterminate and chronic stages of Chagas disease in the mouse model. We report, for the first time, the effect of HFD on myocardial inflammation, vasculopathy, and other types of dysfunction observed during chronic T. cruzi infection. Our results show that HFD perturbs lipid metabolism and induces oxidative stress to exacerbate late chronic Chagas disease cardiac pathology.

Integration of miRNA and gene expression profiles suggest a role for miRNAs in the pathobiological processes of acute Trypanosoma cruzi infection

Chagas disease, caused by the parasite Trypanosoma cruzi, is endemic in Latin America. Its acute phase is associated with high parasitism, myocarditis and profound myocardial gene expression changes. A chronic phase ensues where 30% develop severe heart lesions. Mouse models of T. cruzi infection have been used to study heart damage in Chagas disease. The aim of this study was to provide an interactome between miRNAs and their targetome in Chagas heart disease by integrating gene and microRNA expression profiling data from hearts of T. cruzi infected mice. Gene expression profiling revealed enrichment in biological processes and pathways associated with immune response and metabolism. Pathways, functional and upstream regulator analysis of the intersections between predicted targets of differentially expressed microRNAs and differentially expressed mRNAs revealed enrichment in biological processes and pathways such as IFNγ, TNFα, NF-kB signaling signatures, CTL-mediated apoptosis, mitochondrial dysfunction, and Nrf2-modulated antioxidative responses. We also observed enrichment in other key heart disease-related processes like myocarditis, fibrosis, hypertrophy and arrhythmia. Our correlation study suggests that miRNAs may be implicated in the pathophysiological processes taking place the hearts of acutely T. cruzi-infected mice.