Insulin alone or with captopril: effects on signaling pathways (AKT and AMPK) and oxidative balance after ischemia-reperfusion in isolated hearts

Autor(es)

de Oliveira, Ubirajara Oliveira ^{[1, 2]} ; Bello-Kein, Adriane ^[1] ; de Oliveira, Alvaro Reischak ^[3] ; Kuchaski, Luiz Carlos ^[2] ; Machado, Ubiratan Fabres ^[4] ; Irigoyen, Maria Claudia ^{[1, 5]} ; Schaan, Beatriz D'Agord ^[6]

Afiliação do(s) autor(es)

^[1] Univ Fed Rio Grande do Sul, ICBS, Dept Physiol, Lab Cardiovasc Physiol, Porto Alegre, RS - Brazil

^[2] Univ Fed Rio Grande do Sul, ICBS, Dept Physiol, Lab Metab & Comparat Endocrinol, Porto Alegre, RS - Brazil

^[3] Univ Fed Rio Grande do Sul, Escola Educ Fis, Lab Res Exercise, Porto Alegre, RS - Brazil

^[4] Univ Sao Paulo, ICB, Dept Physiol & Biophys, BR-09500900 Sao Paulo - Brazil

^[5] HC FMUSP, Inst Coracao, Hypertens Unit, Lab Expt Hypertens, Sao Paulo - Brazil

^[6] Univ Fed Rio Grande do Sul, HCPA, Dept Internal Med, Div Endocrine, Porto Alegre, RS - Brazil

• Tipo de documento: Artigo Científico
• Fonte: FUNDAMENTAL & CLINICAL PHARMACOLOGY; v. 26, n. 6, p. 679-689, DEC 2012.
• Citações Web of Science: 6

Resumo

Insulin and the inhibition of the reninangiotensin system have independent benefits for ischemiareperfusion injury, but their combination has not been tested. Our aim was to evaluate the effects of insulin+captopril on insulin/angiotensin signaling pathways and cardiac function in the isolated heart subjected to ischemiareperfusion. Isolated hearts were perfused (Langendorff technique) with KrebsHenseleit (KH) buffer for 25 min. Global ischemia was induced (20 min), followed by reperfusion (30 min) with KH (group KH), KH+angiotensin-I (group A), KH+angiotensin-I+captopril (group AC), KH+insulin (group I), KH+insulin+angiotensin-I (group IA), or KH+insulin+angiotensin-I+captopril (group IAC). Group A had a 24% reduction in developed pressure and an increase in end-diastolic pressure vs. baseline, effects that were reverted in groups AC, IA, and IAC. The phosphorylation of protein kinase B (AKT) was higher in groups I and IA vs. groups KH and A. The phosphorylation of AMP-activated protein kinase (AMPK) was similar to 31% higher in groups I, IA, and IAC vs. groups KH, A, and AC. The tert-butyl hydroperoxide (tBOOH)-induced chemiluminescence was lower (similar to 2.2 times) in all groups vs. group KH and was similar to 35% lower in group IA vs. group A. Superoxide dismutase content was lower in groups A, AC, and IAC vs. group KH. Catalase activity was similar to 28% lower in all groups (except group IA) vs. group KH. During reperfusion of the ischemic heart, insulin activates the AKT and AMPK pathways and inhibits the deleterious effects of angiotensin-I perfusion on SOD expression and cardiac function. The addition of captopril does not potentiate these effects. (AU)

• Processo FAPESP: 07/50554-1 - Transportadores de glicose e Diabetes mellitus: contribuição ao conhecimento da regulação da glicemia e do desenvolvimento de complicações
• Beneficiário: Ubiratan Fabres Machado
• Modalidade de apoio: Auxílio à Pesquisa - Temático