Universidade Federal de Minas Gerais, Belo Horizonte, MG - Brasil.
Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo, Ribeirão Preto, SP - Brasil.
Arq Bras Cardiol. 2024 Sep 9;121(8):e20230707. doi: 10.36660/abc.20230707. eCollection 2024.
Chronic Chagas cardiomyopathy (CCC) is caused by an inflammatory process induced by Trypanosoma cruzi, which leads to myocarditis with reactive and reparative fibrosis. CCC progresses with myocardial perfusion abnormalities and histopathological events that affect cardiorespiratory fitness (CRF).
We evaluated the effects of aerobic physical training (APT) on myocardial perfusion and on morphological and functional impairments related with inflammation and fibrosis in Syrian hamsters with CCC. As a secondary objective, we analyzed the cross-sectional areas of the skeletal muscle.
Hamsters with CCC and their respective controls were divided into four groups: CCC sedentary, CCC-APT, sedentary control and APT control. Seven months after infection, the animals underwent echocardiography, myocardial perfusion scintigraphy and cardiopulmonary exercise testing. Moderate-intensity APT was performed for fifty minutes, five times a week, for eight weeks. Subsequently, the animals were reassessed. Histopathological analysis was conducted after the above-mentioned procedures. The level of significance was set at 5% in all analyses (p<0.05).
CCC sedentary animals presented worse myocardial perfusion defects (MPD) over time, reduced left ventricle ejection fraction (LVEF) and showed more inflammation and fibrosis when compared to other groups (mixed ANOVA analysis). Conversely, APT was able to mitigate the progression of MPD, ameliorate inflammation and fibrosis and improve CRF efficiency in CCC-APT animals.
Our study demonstrated that APT ameliorated cardiac dysfunction, MPD, and reduced inflammation and fibrosis in CCC hamster models. Additionally, CCC-SED animals presented skeletal muscle atrophy while CCC-APT animals showed preserved skeletal muscle CSA. Understanding APT's effects on CCC's pathophysiological dimensions is crucial for future research and therapeutic interventions.
慢性恰加斯心肌病（CCC）是由克氏锥虫引起的炎症过程引起的，导致心肌炎伴反应性和修复性纤维化。CCC 随着心肌灌注异常和影响心肺适应能力（CRF）的组织病理学事件而进展。
我们评估了有氧运动训练（APT）对伴有 CCC 的叙利亚仓鼠心肌灌注的影响，以及对与炎症和纤维化相关的形态和功能损伤的影响。作为次要目标，我们分析了骨骼肌的横截面积。
感染七个月后，CCC 久坐不动的仓鼠及其各自的对照组被分为四组：CCC 久坐不动、CCC-APT、久坐不动对照和 APT 对照。在感染后七个月，动物接受了超声心动图、心肌灌注闪烁显像和心肺运动测试。中等强度的 APT 每周进行 5 次，每次 50 分钟，持续 8 周。随后，对动物进行重新评估。在进行上述程序后进行组织病理学分析。所有分析的显著性水平均设为 5%（p<0.05）。
与其他组相比，CCC 久坐不动的动物随着时间的推移出现更严重的心肌灌注缺陷（MPD）、左心室射血分数（LVEF）降低，并且表现出更多的炎症和纤维化（混合方差分析）。相反，APT 能够减轻 MPD 的进展，改善炎症和纤维化，并提高 CCC-APT 动物的 CRF 效率。
我们的研究表明，APT 改善了 CCC 仓鼠模型的心脏功能障碍、MPD，并减少了炎症和纤维化。此外，CCC-SED 动物表现出骨骼肌萎缩，而 CCC-APT 动物表现出保留的骨骼肌 CSA。了解 APT 对 CCC 病理生理维度的影响对于未来的研究和治疗干预至关重要。
