RESUMO
Single nucleotide polymorphisms (SNPs) in vascular endothelial growth factor receptor 2 (VEGFR2) are associated with coronary artery disease, hypertension and myocardial infarction. However, their association with atherosclerosis remains to be fully elucidated. The purpose of the present study was to determine whether SNPs are involved in atherogenesis, by analyzing their impact on human umbilical vein endothelial cells (HUVECs) under laminar and nonuniform shear stress in a wellestablished in vitro model that simulates shear stressinduced proatherogenic processes at vessel bifurcations. All experiments were performed using freshly isolated HUVECs. Three SNPs in the VEGFR2 gene (rs1870377 T>A, rs2071559 A>G and rs2305948 C>T) were genotyped and the expression levels of VEGFR2 were semiquantitatively determined using western blotting. Subsequently, the HUVECs were seeded in bifurcating flowthrough cell culture slides and flow (9.6 ml/min) was applied for 19 h, including tumor necrosis factorα stimulation during the final 2 h of flow. The protein expression levels of VCAM1, Eselectin and VEGFR2 and the adhesion of THP1 cells were analyzed in laminar and nonuniform shear stress regions. Data were analyzed for associations with the respective SNPs. The total expression of VEGFR2 was significantly lower under nonuniform shear stress than under laminar shear stress conditions, independent of the genotype. The expression of VEGFR2 between the different shear stress patterns was not significantly altered by the different SNPs. The expression levels of VCAM1 and Eselectin were lower in the A/A genotype compared with those in other genotypes in rs1870377 T>A and rs2071559 A>G. In conclusion, the results suggested that SNPs within the VEGFR2 gene have a significant impact on shear stressrelated endothelial activation.