Glucose and fatty acid metabolism in infarcted heart from streptozotocin-induced diabetic rats after 2 weeks of tissue remodeling

Author(s)

Malfitano, Christiane ^{[1, 2]} ; de Souza Junior, Alcione Lescano ^{[2, 3]} ; Carbonaro, Mariana ^[1] ; Bolsoni-Lopes, Andressa ^[2] ; Figueroa, Diego ^[1] ; de Souza, Leandro Ezequiel ^[1] ; Santos Silva, Kleiton Augusto ^[4] ; Consolim-Colombo, Fernanda ^{[1, 5]} ; Curi, Rui ^[2] ; Irigoyen, Maria Claudia ^{[1, 5]}

Affiliation

^[1] Univ Sao Paulo, Sch Med, Hypertens Unit, Heart Inst InCor, BR-05403000 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, BR-05403000 Sao Paulo, SP - Brazil

^[3] Univ Estado Mato Grosso, Dept Nursing, Alta Floresta - Brazil

^[4] Univ Sao Paulo, Sch Med Fed, Dept Nephrol, BR-05403000 Sao Paulo, SP - Brazil

^[5] Univ Nove Julho, Lab Translat Physiol, Sao Paulo - Brazil

• Document type: Journal article
• Source: CARDIOVASCULAR DIABETOLOGY; v. 14, NOV 9 2015.
• Web of Science Citations: 16

Abstract

Background: The effects of streptozotocin (STZ)-induced diabetes on heart metabolism and function after myocardial infarction (MI) remodelling were investigated in rats. Methods: Fifteen days after STZ (50 mg/kg b.w. i.v.) injection, MI was induced by surgical occlusion of the left coronary artery. Two weeks after MI induction, contents of glycogen, ATP, free fatty acids and triacylglycerols (TG) and enzyme activities of glycolysis and Krebs cycle (hexokinase, glucose-6-phosphate dehydrogenase, phosphofructokinase, citrate synthase) and expression of carnitine palmitoyl-CoA transferase I (a key enzyme of mitochondrial fatty acid oxidation) were measured in the left ventricle (LV). Plasma glucose, free fatty acids and triacylglycerol levels were determined. Ejection fraction (EF) and shortening fraction (SF) were also measured by echocardiography. Results: Glycogen and TG contents were increased (p < 0.05) whereas ATP content was decreased in the LV of the non-infarcted diabetic group when compared to the control group (p < 0.05). When compared to infarcted control rats (MI), the diabetic infarcted rats (DI) showed (p < 0.05): increased plasma glucose and TG levels, elevated free fatty acid levels and increased activity of, citrate synthase and decreased ATP levels in the LV. Infarct size was smaller in the DI group when compared to MI rats (p < 0.05), and this was associated with higher EF and SF (p < 0.05). Conclusions: Systolic function was preserved or recovered more efficiently in the heart from diabetic rats two weeks after MI, possibly due to the high provision of glucose and free fatty acids from both plasma and heart glycogen and triacylglycerol stores. (AU)

• FAPESP's process: 13/11463-1 - Lipid profile and oxidative stress in heart protection induced diabetic hyperglycemia: reviews after myocardial infarction
• Grantee: Camila Paixão dos Santos
• Support Opportunities: Scholarships in Brazil - Scientific Initiation