Figure 2.

Repulsive guidance molecule a (RGMa) suppressed VEGF expression, phosphorylation of focal adhesion kinase (FAK), proliferation, migration, and tube formation in ECs. (A,B) Lysate was collected, and VEGF was detected by western blot in human umbilical artery endothelial cells (HUAECs) treated with RGMa (2 µg/ml); (C–E) ELISA kit assay showed VEGFA decreased in endothelial cell (EC)-culture supernatant exposed to RGMa compared with cell-culture supernatant from control group. (F–H) Cell proliferation was evaluated with cell-counting kit-8 and 5-ethynyl-2′-deoxyuridine (EdU) assays (I,J). RGMa decreased proliferation of ECs stimulated and unstimulated with VEGF. (K,L) FAK (Tyr397) phosphorylation was measured with western blot in HUAECs treated with vehicle, RGMa (2 µg/ml), VEGF (50 ng/ml), or VEGF plus RGMa. (M–P) ECs were grown to 100% confluence, serum-starved overnight, wounded with a sterile pipette tip to remove cells, and treated with control, RGMa, VEGF, or VEGF plus RGMa. Photographs (40×) were taken at 12 h after injury. Wound closure of ≥3 wells was quantified and reported as mean ± SD. (Q–T) Migration activity of ECs treated with RGMa, VEGF, VEGF plus RGMa, or control was measured with transwell assay. Photographs (200×) were taken 18 h after treatment. (U–X) HUAECs were starved overnight, treated as indicated, and seeded into 96-well plates coated with Matrigel. Photographs (40×) were taken at 3 h after treatment. The number of tubes, tube area, and tube length were analyzed with Image J. Scale bar, 100 µm. Data shown are representative of experimental and quantitative results. N ≥ 4 independent experiments. Bars represent mean ± SD. *P < 0.05, **P < 0.01, ***P < 0.001.