Calcium homeostasis behavior and cardiac function on left ventricular remodeling by pressure overload

Autor(es)

Mazeto, I. F. S. ^[1] ; Okoshi, K. ^[2] ; Silveira, C. F. S. M. P. ^[2] ; Sant'Ana, P. G. ^[2] ; da Silva, V. L. ^[2] ; Mota, G. A. F. ^[2] ; de Souza, S. L. B. ^[2] ; Vileigas, D. F. ^[2] ; Padovani, C. R. ^[3] ; Cicogna, A. C. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Paulista, Fac Med Botucatu, Dept Infectol Demiatol Diagnost Imagem & Radioter, Botucatu, SP - Brazil

^[2] Univ Estadual Paulista, Fac Med Botucatu, Dept Clin Med, Botucatu, SP - Brazil

^[3] Univ Estadual Paulista, Inst Biociencias, Botucatu, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 54, n. 4 2021.
• Citações Web of Science: 0

Resumo

Sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) and sarcolemmal Na+/Ca2+ exchanger (NCX1) structures are involved in heart cell Ca2+ homeostasis. Previous studies have shown discrepancies in their function and expression in heart failure. The goal of this study was to evaluate heart function and hypertrophied muscle Ca2+-handling protein behavior under pressure overload. Twenty male Wistar rats were divided into two groups: Aortic stenosis (AoS), induced by a clip placed at the beginning of the aorta, and Control (Sham). After 18 weeks, heart function and structure were evaluated by echocardiogram. Myocardial function was analyzed by isolated papillary muscle (IPM) at basal condition and Ca2+ protein functions were evaluated after post-pause contraction and blockage with cyclopiazonic acid in IPM. Ca2+-handling protein expression was studied by western blot (WB). Echocardiogram showed that AoS caused concentric hypertrophy with enhanced ejection fraction and diastolic dysfunction inferred by dilated left atrium and increased relative wall thickness. IPM study showed developed tension was the same in both groups. AoS showed increased stiffness revealed by enhanced resting tension, and changes in Ca2+ homeostasis shown by calcium elevation and SERCA2a blockage maneuvers. WB revealed decreased NCX1, SERCA2a, and phosphorylated phospholambam (PLB) on serine-16 in AoS. AoS had left ventricular hypertrophy and diastolic dysfunction compared to Sham; this could be related to our findings regarding calcium homeostasis behavior: deficit in NCX1, SERCA2a, and phosphorylated PLB on serine-16. (AU)

• Processo FAPESP: 11/21366-8 - Avaliação da participação da SERCA2a na disfunção diastólica do ventrículo esquerdo em ratos submetidos à estenose aórtica supravalvar
• Beneficiário: Antonio Carlos Cicogna
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/09830-6 - Avaliação da participação da SERCA2a cardíaca em ratos submetidos à estenose aórtica supravalvar com disfunção cardíaca
• Beneficiário: Izabelle Ferreira da Silva Mazeto
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica