Early Growth Response Protein 1 Promotes Restenosis by Upregulating Intercellular Adhesion Molecule-1 in Vein Graft

Objectives . To verify the relationship between Egr-1 and vein graft restenosis and investigate the related mechanisms. Methods . Mouse vein graft models were established in Egr-1 knockout (KO) and wild-type (WT) mice. The vein grafts in the mice were taken for pathological examination and immunohistochemical analysis. The endothelial cells (ECs) were stimulated by using a computer-controlled cyclic stress unit. BrdU staining and PCR were used to detect ECs proliferation activity and Egr-1 and ICAM-1 mRNA expression, respectively. Western-blot analysis was also used to detect expression of Egr-1 and intercellular adhesion molecule-1 (ICAM-1) proteins. Results . The lumens of vein grafts in Egr-1 KO mice were wider than in WT mice. ECs proliferation after mechanical stretch stimulation was suppressed by Egr-1 knockout ( P < 0.05). Both in vein grafts and ECs from WT mice after mechanical stretch stimulation, mRNA expression and protein of Egr-1 and ICAM-1 showed increases ( P < 0.05). However, ICAM-1 expression was significantly suppressed in ECs from Egr-1 knockout mice ( P < 0.05). Conclusions . Egr-1 may promote ECs proliferation and result in vein graft restenosis by upregulating the expression of ICAM-1. As a key factor of vein graft restenosis, it could be a target for the prevention of restenosis after CABG surgery.