Efeitos do treinamento físico aeróbico na função cardíaca, capacidade funcional, comportamento depressivo e níveis de neurotrofinas em camundongos infectados pela cepa y do Trypanosoma cruzi

Abstract

Aims: To investigate the effects of moderate aerobic physical training on cardiac function and morphology as well as on the levels of glial cell-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) of animals infected with the Y strain of Trypanosoma cruzi. Main methods: Twenty-eight male C57BL/6 mice were distributed into 4 groups: sedentary control (SC), trained control (TC), sedentary infected (CHC) and trained infected (CHT). The infection was performed by intraperitoneal injection of trypomastigote forms and the animals were adapted to treadmill in the week before the beginning of the training protocol, initiated 45 days post infection. On the last day of adaptation, as well as at the end of the 4th, 8th and 12th weeks of training, the maximal exercise test (TEM) was performed to establish the adjustments in training speed. At the end of the 12th week, all animals were evaluated for cardiac morphology and function by echocardiography. Key findings: CHC group showed a larger area of right ventricle and increased end-systolic volume, as well as reduction in ejection fraction, stroke volume, cardiac output and fractional area change. GDNF level was higher in TC and CHC groups compared to SC in heart and BDNF levels were higher in CHC compared to SC in heart and serum. Significance: Physical training ameliorated the cardiac function of infected animals and promotes adjusts in BDNF and GDNF levels suggesting it as possible markers of cardiac dysfunction responsive to exercise stimulus.