Grb2-Associated Binder1 Is Essential For Umbilical Vein Endothelial Cells Against Ischemia/Reperfusion Injury

Objectives: Growth factor receptor binding protein 2 binding protein 1(Gab1)is an adaptor protein that plays a critical role in cardiac protection during ischemia-reperfusion injury.The purpose of this study was to investigate the effect of overexpression of Gab1 protein on umbilical vein endothelial cells during ischemia-reperfusion injury and its molecular mechanism.Materials and Methods: Umbilical vein endothelial cells cultured to 5 generations were divided into normal control group,hypoxia/reoxygenation group and hypoxia/reoxygenation +Gab1 group.After 2 hours of cell planking,change to sugar-free medium.The anoxia/reoxygenation group and the anoxia/reoxygenation+Gab1 group were placed in a three-gas incubator(5%CO2,94%N2,1%O2)for anoxia culture for 6 hours,and then the complete medium was placed in a normal incubator for reoxygenation for 16 hours.Before hypoxia/reoxygenation +Gab1 group was transfected with adenovirus containing Gab1 gene to improve the expression of Gab1 in cells.The normal control group was always cultured in normal incubator for 24 hours.MTT colorimetric method and TUNEL method were used to detect the proliferation and apoptosis rate of cells,and the effect of Gab1 on ROS and LDH in umbilical vein endothelial cells was observed.Phosphorylation levels of Gab1,SHP2 and erk1/2 were detected by western blot.Results: Compared with the normal control group,the proliferation ability of cells in the anoxia/reoxygenation group was significantly reduced(p<0.05),the apoptosis rate was increased(p<0.05),and intracellular ROS and LDH were significantly higher than those in the normal control group(p<0.05).In the anoxia/reoxygenation +Gab1group,the cell proliferation ability was significantly higher than that of the anoxia/reoxygenation group(p<0.05),the apoptosis rate decreased(p<0.05),and intracellular ROS and LDH were significantly lower than that of the anoxia/reoxygenation group(p<0.05).Phosphorylation levels of Gab1,SHP2 and erk1/2 in anoxia/reoxygenation +Gab1 group were significantly higher than that in anoxia/reoxygenation group.Conclusion: Overexpression of Gab1 has a protective effect on umbilical vein endothelial cells in hypoxia-reoxygenated injury.Overexpression of Gab1 can improve the phosphorylation level of Gab1 protein in cells,thereby increasing the expression of extracellular phosphorylation of erk1/2.Gab1 plays a protective effect on umbilical vein endothelial cells in hypoxia-reoxygenated injury through the erk1/2pathway.