ABSTRACT
AIM:To investigate the effects of DL-3-n-butylphthalidle (NBP) on angiogenesis of human um-bilical vein endothelial cells ( HUVECs) and the role of vascular endothelial growth factor ( VEGF)/VEGF receptor 2 (VEGFR2)-Notch1/Delta-like ligand 4 (Dll4) signaling pathway in this process. METHODS:The serum-free medium and anoxic tank were used to simulate the conditions of hypoxia and ischemia ( H/I). HUVECs were divided into control group, H/I group, H/I+NBPhigh group and H/I+NBPlow group. The HUVECs in control group were conventionally cul-tured, and those in H/I group were cultured under H/I intervention. The HUVECs in H/I+NBPhigh group were treated with NBP at 20 μmol/L under H/I intervention. The HUVECs in H/I+NBPlow group were treated with NBP at 5 μmol/L under H/I intervention. The cell viability of each group was measured by CCK-8 assay. The migration ability of the HUVECs in each group was detected by cell scratch test. The vessel formation ability of the HUVECs was examined by in vitro angiogenesis assay. The expression of VEGFR2, Notch1 and Dll4 at mRNA and protein levels was determined by qPCR and Western blot, and the expression of VEGF was determined by qPCR and ELISA. RESULTS:NBP increased the viability of HUVECs, and promoted the migration ability and the formation of blood vessels in vitro under H/I interven-tion. These effects of NBP at high dose were more significant than those at low dose. NBP increased the expression of VEGF, VEGFR2, Notch1 and Dll4 at mRNA and protein levels (P<0.05). CONCLUSION:NBP promotes HUVECs to form blood vessels under H/I intervention. The mechanism may be related to the activation of VEGF/VEGFR2-Notch1/Dll4 signaling pathway.