[Effects of a triple mutant hypoxia-inducible factor-1α on proliferation and vascular endothelial growth factor expression in human microvascular endothelial cells].

Objective: To investigate the effects of a recombinant adenovirus-mediated triple mutant hypoxia-inducible factor-1α (HIF-1α) on the proliferation and vascular endothelial growth factor (VEGF) expression in human microvascular endothelial cells (hMVECs).

Methods: The adenovirus vector of the triple mutant HIF-1α (Ad-HIF-1α(564/402/803)), adenovirus vector of wild-type HIF-1α (Ad-HIF-1α(nature)), Ad-lacZ and Ad-Null were amplified in HEK293A cells, and the adenoviruses were purified and titrated. Dual luciferase reporter assay system was employed to detect the transcriptional activities of wild-type and triple mutant HIF-1α. After infection of the hMVECs with the adenoviruses, the cellular protein expressions of HIF-1α and VEGF were detected using Western blotting, and the cell proliferation was assessed by MTS assay.

Results: The transcriptional activity of the triple mutant HIF-1α was significantly higher than that of wildtype HIF-1α in the infected hMVECs (P<0.001). The protein levels of HIF-1α and VEGF in cells infected with Ad-HIF-1α(564/402/803) were significantly higher than those in cells infected with other adenoviruses, and HIF-1α dose-dependently up-regulated VEGF protein expression. The absorbance was significantly higher in Ad-HIF-1α(564/402/803) group than in the other groups (P<0.01) on the third and fifth days after infection.

Conclusion: The recombinant adenovirus-mediated triple mutant HIF-1α expression is stable under normoxic condition. The triple mutant HIF-1α can up-regulate the expression of VEGF protein in hMVECs to promote the cell proliferation.