Alpha-lipoic acid enhances ischemic postconditioning-mediated improvement of myocardial infarction and apoptosis in diabetic rats with ischemia/reperfusion injury

Abstract

This work evaluated the combined effects of alpha-lipoic acid (ALA) and ischemic-postconditioning (Post) on myocardial infarction and cell death in rats with chronic type-2 diabetes following ischemia/reperfusion injury. The rats received a high-fat diet and were given one intraperitoneal injection of 35 mg/kg streptozotocin to induce chronic diabetes. They were then pretreated with ALA (100 mg/kg/day, orally) for five weeks before undergoing I/R insult. The hearts experienced 35-minute regional ischemia through ligating the left anterior descending coronary artery, followed by 60-minute reperfusion. The Post protocol involved six cycles of a 10/10 seconds algorithm, applied during the early stage of reperfusion. The use of Post alone did not significantly alter LDH and infarct size (IS) levels, while ALA showed positive effects. Similar findings were observed for apoptotic changes with single treatments. However, the concurrent administration of ALA and Post significantly reduced the protein expression of Bax, Bax/Bcl2, and cleaved caspase-3, while increasing Bcl2 expression. Additionally, the histopathological findings of the combined therapy were superior to those of single treatments. The concomitant use of ALA and Post effectively inhibited apoptosis, leading to cardiac recovery after I/R injury in diabetic conditions. This strategy could improve outcomes for preserving diabetic hearts following I/R insults.