Swimming Training Improves Myocardial Mechanics, Prevents Fibrosis, and Alters Expression of Ca2+ Handling Proteins in Older Rats

Autor(es):Mostrar menos -

Yoshizaki, Amanda ^[1] ; Antonio, Ednei Luiz ^[1] ; Silva Junior, Jose Antonio ^[2] ; Crajoinas, Renato Oliveira ^[3] ; Silva, Flavio Andre ^[1] ; Costa Girardi, Adriana Castello ^[3] ; Bocalini, Danilo Sales ^[4] ; Portes, Leslie Andrews ^[5] ; Neves dos Santos, Luis Felipe ^[1] ; Carlos, Fernando Pereira ^[2] ; Camillo de Carvalho, Paulo de Tarso ^[2] ; Ferreira Tucci, Paulo Jose ^[1] ; Serra, Andrey Jorge ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Sao Paulo - Brazil

^[2] Nove Julho Univ, Lab Biophoton, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Heart Inst InCor, Sao Paulo - Brazil

^[4] Univ Fed Espirito Santo, Ctr Phys Educ & Sport, Sao Paulo - Brazil

^[5] UNASP Adventist Univ, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNALS OF GERONTOLOGY SERIES A-BIOLOGICAL SCIENCES AND MEDICAL SCIENCES; v. 73, n. 4, p. 468-474, APR 2018.
• Citações Web of Science: 0

Resumo

Exercise training effects on the contractility of aged myocardium have been investigated for more than 20 years, but the data are still unclear. This study evaluated the hypothesis that a swimming training (ST) may improve myocardial inotropism in older rats. Male Wistar rats aged 4 (young)-and 21 (old)-months-old were divided into young untrained (YNT), old untrained (ONT), and old trained (OTR; 6 weeks of ST) groups. Echocardiography and hemodynamic were employed to assess left ventricular morphology and function. Myocardial mechanics was evaluated on papillary muscles. Histological and immunoblotting were carried out to evaluate fibrosis and proteins that modulate the myocardial function and calcium handling. We found that older rats did not show cardiac dysfunction, but ONT group showed lower physical performance during a swimming test (YNT: 5 +/- 2; ONT: -16 +/- 0.4; OTR: 51 +/- 3; Delta%, sec). Moreover, ONT group showed worse myocardial inotropism, in which it was reversed by ST (Peak developed tension: YNT: 6.2 +/- 0.7; ONT: 3.9 +/- 0.3; OTR: 6.9 +/- 0.9; g/mm(2)). The ST was associated with preserved collagen content (YNT: 0.38 +/- 0.05; ONT: 0.78 +/- 0.12; OTR: 0.34 +/- 0.09; %). Exercise partially mitigated the effects of aging on intracellular Ca2+-regulating protein (eg, L-Ca2+ channel and phospholamban) and beta-isoform of myosin. Thus, we propose that these molecular alterations together with inhibition of collagen increase contribute to improved myocardial performance in older rats. (AU)

• Processo FAPESP: 13/10619-8 - Dipeptidil peptidase IV como um potencial alvo para a terapia da insuficiência cardíaca
• Beneficiário: Adriana Castello Costa Girardi
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 15/11028-9 - A modalidade de treinamento físico aeróbio pode determinar a existência de remodelamento cardíaco: identificando peculiaridades estruturais, funcionais e moleculares dos modelos experimentais de natação e corrida
• Beneficiário: Andrey Jorge Serra
• Modalidade de apoio: Auxílio à Pesquisa - Regular