Article
Physical Exercise Promotes a Reduction in Cardiac Fibrosis in the Chronic Indeterminate Form of Experimental Chagas Disease
Registro en:
REZENDE, Yasmin Pedra et al. Physical Exercise Promotes a Reduction in Cardiac Fibrosis in the Chronic Indeterminate Form of Experimental Chagas Disease. Frontiers in Immunology. v. 12, Article 12034, p. 1-19, Nov. 2021.
1664-3224
10.3389/fimmu.2021.712034
Autor
Rezende, Yasmin Pedra
Barbosa, Juliana M. C.
Bombaça, Ana Cristina S.
Pereira, Luiza Dantas
Gibaldi, Daniel
Pereira, Glaucia Vilar
Santos, Hílton Antônio Mata dos
Ramos, Isalira Peroba
Gomes, Natália Lins Silva
Moreira, Otacilio C.
Vieira, Joseli Lannes
Menna-Barreto, Rubem F. S.
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. Yinfected
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.