Effect of ginkgo diterpene lactones on hypoxia-induced apoptosis and angiogenesis of human umbilical vein endothelial cells and its mechanisms / 第二军医大学学报

ABSTRACT

Objective To investigate the effect of ginkgo diterpene lactones on hypoxia-induced apoptosis and angiogenesis of human umbilical vein endothelial cells (HUVECs) and the related molecular mechanisms. Methods HUVECs were cultured under hypoxia for 24 h, and then treated with ginkgo diterpene lactones (low-dose 6.25 mg/L and high-dose 25.00 mg/L). MTT assay was used to detect the cell activity. Flow cytometry was used to detect the apoptosis of HUVECs. Transwell assay was employed to detect the migration of HUVECs. Quantitative real-time polymerase chain reaction and Western blotting were used to test the expression levels of mRNA and protein of hypoxia-inducible factor 1α (HIF-1α), apoptosis-related genes (B-cell lymphoma 2［Bcl-2］and B-cell lymphoma 2-related X protein［Bax］), and angiogenesis-related genes (vascular endothelial growth factor［VEGF］and transforming growth factor β［TGF-β］). Results Compared with the normal group, the HUVEC activity was significantly decreased after exposed to hypoxia for 24 h (P＜0.05), and the apoptosis rate of HUVECs and mRNA and protein expression levels of HIF-1α were significantly higher (all P＜0.05). The cell activity and migration ability of HUVECs were significantly higher in the low- and high-dose ginkgo diterpene lactones groups than those in the hypoxia group (all P＜0.05), and the apoptosis rates of HUVECs were significantly lower than those in the hypoxia group (both P＜0.05). Meanwhile, the cell activity and migration ability were significantly higher in the high-dose group than those in the low-dose group (both P＜0.05), and the apoptosis rate was significantly lower than that in the low-dose group (P＜0.05). The mRNA and protein expression levels of HIF-1α and Bax were lower in the low- and high-dose ginkgo diterpene lactones groups than those in the hypoxia group, and the mRNA and protein expression levels of Bcl-2, VEGF and TGF-β were higher than those in the hypoxia group; and the expression changes of the above genes were more significant in the high-dose group. Conclusion Ginkgo diterpene lactones can improve hypoxia-induced apoptosis and angiogenesis of HUVECs by regulating the expression levels of HIF-1α and apoptosis- and angiogenesis-related genes, and it might be used as a new agent to treat anoxic vascular diseases.