Figure 4. Inhibition of HIF-1α decreased the expression and transcriptional activity of YAP as well as EndMT in HUVECs, but inhibiting phosphorylation of YAP promoted the activity of YAP.

A: HUVECs were treated with 300 µmol/L CoCl₂ and YC-1 (1 µmol/L) for 24h. HIF-1α, YAP, CTGF and proteins of EndMT were detected by Western blotting. B: YAP was observed by immunostaining and scale bar represents 100 µm. C: Ki67 (green) and DAPI (blue) immunostaining was used to analyze proliferative capacity of hypoxic HUVECs. Scale bar represents 200 µm. D, E: Scratch healing experiments were performed to examine the effect of YC-1 on the migration ability of 300 µmol/L CoCl₂-induced hypoxic HUVECs. Scale bar represents 500 µm. All the results were expressed as mean±SD (n=3). ^aP < 0.05. HIF-1α: Hypoxia-inducible factor-1α; YAP: Yes-associated protein; EndMT: Endothelial-to-mesenchymal transition; HUVECs: Human umbilical vein endothelial cells; CTGF: Connective tissue growth factor.