Effectiveness of a single versus repeated administration of trimetazidine in the protection against warm ischemia/reperfusion injury of rat liver

[Background/aim] The aim of this study was to compare the effects of single and repeated trimetazidine (TMZ) administration against warm hepatic ischemia/reperfusion (I/R) injury and to explore the possible mechanisms affected by TMZ. [Materials and methods] Wistar rats were divided into 4 groups (n = 6). Sham: rats were subjected to dissection. I/R: rats were subjected to 60 min of partial hepatic ischemia followed by 24 h of reperfusion. TMZ1: Same as I/R group but rats were pretreated with a single dose of TMZ (10 mg/kg, intraperitoneal injection) 30 min before warm ischemia. TMZ3: Same as I/R but rats were treated with 10 mg/ kg TMZ for 3 successive days. [Results] TMZ treatment decreased liver injury, lipid peroxidation, and apoptosis. The repeated administration of TMZ conferred more protection than the single dose treatment concerning all studied parameters. In parallel, we noted a significant increase in phosphorylated adenosine monophosphate activated protein kinase (p-AMPK) and endothelial nitric oxide synthase (eNOS) levels in TMZ3 as compared to TMZ1. [Conclusion] Repeated administration of TMZ for 3 days was more efficient than a single dose of TMZ in protecting the liver against I/R induced apoptosis and lipid peroxidation. These effects implicate AMPK and eNOS activation.This study was funded by the Tunisian Ministry of Higher Education and Scientific Research.Peer Reviewe

Effects of trimetazidine on the Akt/eNOS signaling pathway and oxidative stress in an in vivo rat model of renal ischemia-reperfusion

© 2014 Informa Healthcare USA, Inc. All rights reserved. Renal ischemia reperfusion (I/R) injury, which occurs during renal surgery or transplantation, is the major cause of acute renal failure. Trimetazidine (TMZ), an anti-ischemic drug, protects kidney against the deleterious effects of I/R. However its protective mechanism remains unclear. The aim of this study is to examine the relevance of Akt, endothelial nitric oxide synthase (eNOS), and hypoxia inducible factor-1α (HIF-1α) on TMZ induced protection of kidneys against I/R injury. Wistar rats were subjected to 60 min of warm renal ischemia followed by 120 min of reperfusion, or to intraperitoneal injection of TMZ (3 mg/kg) 30 min before ischemia. In sham operated group renal pedicles were only dissected. Compared to I/R, TMZ treatment decreased lactate dehydrogenase (845 ± 13 vs. 1028 ± 30 U/L). In addition, creatinine clearance and sodium reabsorption rates reached 105 ± 12 versus 31 ± 11 μL/min/g kidney weight and 95 ± 1 versus 68 ± 5%, respectively. Besides, we noted a decrease in malondialdehyde concentration (0.33 ± 0.01 vs. 0.59 ± 0.03 nmol/mg of protein) and an increase in glutathione concentration (2.6 ± 0.2 vs. 0.93 ± 0.16 μg GSH/mg of protein), glutathione peroxidase (95 ± 4 vs. 61 ± 3 μg GSH/min/mg of protein), and superoxide dismutase (25 ± 3 vs. 11 ± 2 U/mg of protein) and catalase (91 ± 12 vs. 38 ± 9 μmol/min/mg of protein) activities. Parallely, we noted a significant increase in p-Akt, eNOS, nitrite and nitrate (18 ± 2 vs. 8 ± 0.1 pomL/mg of protein), HIF-1α (333 ± 48 vs. 177 ± 14 μg/mg of protein) and heme oxygenase-1 (HO-1) levels regarding I/R. TMZ treatment improves renal tolerance to warm I/R. Such protection implicates an activation of Akt/eNOS signaling pathway, HIF-1α stabilization and HO-1 activation.Peer Reviewe