O exercício físico na insuficiência cardíaca secundária à quimioterapia baseada em antraciclinas

• Autor(a) principal: Sequeira, Cláudia de Morais
• Data de Publicação: 2021
• Outros Autores: [e-mail]
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/19809
• topic: Resistance exercise; Doxorubicin; Vascular reactivity; Cardiac function; Exercício resistido; Doxorrubicina; Reatividade vascular; Função cardíaca; CIENCIAS DA SAUDE::MEDICINA

Several preclinical studies demonstrate that aerobic exercise reduces cardiac toxicity induced by doxorubicin (Dox). However, little is known about the effects of resistance training (RT) on the cardiovascular changes induced by Dox, a type of training that is recommended to be included in a rehabilitation program for cancer patients given its effectiveness in maintaining muscle mass and strength, and may contribute to maintenance of the patient's quality of life. The aim of the study was to investigate the effects of TR on cardiac morphofunctionality and vascular reactivity in an experimental model of Dox-induced toxicity. Adult Sprague Dawley rats were divided into three groups: (1) Control; (2) Dox + sedentary (Dox+Sed); (3) Dox + TR. The RT was performed 5x/week, for 8 weeks, and consisted of climbing a 54-step vertical ladder. Dox was administered for 10 consecutive days (1 mg/kg/day, i.p., total dose 10 mg/kg). Survival, body mass, strength test and cardiac function were measured throughout the experimental protocol. After euthanasia, the animals' mesenteric arterial bed was removed and isolated to study vascular reactivity. Fragments of the left ventricle were used to analyze the morphology, ultrastructure of cardiomyocytes, oxidative stress, protein expression of the synthesis and proliferation pathways. Protein expression of the aortic artery homogenate was used to analyze adrenergic signaling, oxidative stress and vascular remodeling. The TR promoted the recovery of the initial body mass (not observed in the Dox+Sed group); increased muscle strength; attenuation of the decrease in ventricular ejection fraction; preservation of morphology and reduction of cardiac fibrosis; increased the activity of the antioxidant enzyme glutathione peroxidase, in addition to greater survival. In the vascular aspect, there was conservation of the endothelium-dependent vasodilator response. Therefore, RT can be used as a useful tool to mitigate the adverse effects of doxorubicin in chemotherapy treatment.