Galanin reduces myocardial ischemia/reperfusion injury in rats with streptozotocin diabetes

Most clinical studies confirm the negative impact diabetes mellitus (DM) has on the course and outcome of cardiovascular complications caused by a myocardial ischemia-reperfusion injury (IRI). In this regard, the search for new approaches to IRI treatment in diabetic myocardium is of undeniable value. The aim of this work was to study the effect of galanin (G) on the size of myocardial infarct (MI), on mitochondrial functions, and on the energy state in the area at risk (AAR) in rats with type 1 diabetes mellitus (DM1) subjected to regional myocardial ischemia and reperfusion. Rat G was obtained by solid-phase synthesis using the Fmoc strategy and purified by HPLC. DM1 was induced by streptozotocin administration. Myocardial IRI was modeled by occlusion of the left anterior descending coronary artery and subsequent reperfusion. G at a dose of 1 mg/kg was administered intravenously before reperfusion. G decreased MI size and plasma creatine kinase MB (CK-MB) activity in DM rats by 40 and 28%, respectively. G injection improved mitochondrial respiration in saponin-skinned fibers in the AAR: namely, the maximal ADP-stimulated state 3, respiratory control, and the functional relationship between the mitochondrial CK-MB and oxidative phosphorylation. G provided significantly higher ATP levels, total adenine nucleotide pool, and adenylate energy charge of cardiomyocytes. It also reduced total creatine loss in myocardial AAR in DM rats. The results suggest there is a possibility of therapeutic use of G in myocardial IRI complicated by DM1.