The effect of Notch1 on myocardial ischemia reperfusion injury

Abstract

To investigate the protective effects of Notch1 on myocardial ischemia reperfusion injury and explore underlying molecular mechanism. H9c2 cells were exposed to hypoxia/reoxygenation (H/R), ischemic preconditioning (IPC) and ischemic postconditioning (IPost) treatment following infection with lentiviral vector-Notch1 intracellular domain (Lv-N1ICD) or Lv-N1ICD-shRNA, and divided into control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group, respectively. Apoptosis was detected by Annexin V/propidium iodide (PI), and reactive oxygen species (ROS) was detected by 2', 7'dichlorofluorescin-diacetate (DCFH-DA). The expression of p-glycogen synthase kinase-3β (p-GSK-3β)/GSK-3β were detected by Western blot analysis. The apoptosis rate of cardiomyocytes in control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group was (5.34±1.70)%, (47.03±4.10)%, (33.89±12.25)%, (35.85±3.17)%, (51.12±8.22)%, (37.35±3.82)%, (47.90±3.08)%, respectively, showing significant differences in all group (F=18.47, P<0.05). ROS in control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group was 624.66±79.52, 1 221.87±63.66, 913.12±115.82, 935.85±201.62, 1 204.03±113.82, 967.15±106.11, 1 296.59±222.38, respectively, showing significant differences in all group (F=8.77, P<0.05). The ratio of p-GSK-3β to GSK-3β in control group, H/R group, H/R+ N1ICD group, IPC group, IPC+ N1ICD-shRNA group, IPost group, IPost+ N1ICD-shRNA group was 0.58±0.12, 0.62±0.20, 1.24±0.09, 1.16±0.12, 0.72±0.15, 1.16±0.12, 0.75±0.12, respectively, showing significant differences in all group (F=11.21, P<0.05). As an endogenous cardioprotective factor, Notch1 reduces myocardial ischemia reperfusion injury by promoting GSK-3β phosphorylation, inhibiting cardiomyocyte apoptosis and reducing ROS formation.