NADPH Oxidase 4-Derived H₂O₂ Promotes Aberrant Retinal Neovascularization via Activation of VEGF Receptor 2 Pathway in Oxygen-Induced Retinopathy

Figure 4

Knockdown of Nox4 in HRECs suppresses endothelial angiogenic response and inhibits VEGFR2 signaling pathway. HRECs were transduced with Ad-Ctrli and Ad-Nox4i for 48 h. (a) Nox4 expression in HRECs was determined by Western blot analysis and semiquantified by densitometry. ; versus Ctrli. (b-c) Migration of HRECs was measured by transwell migration assay (b) and wound healing assay (c). Migrated cell number or gap closure was calculated from 3 different wells. versus Ctrli and versus Ctrliwith VEGF. Results represent 3 independent experiments. (d) Endothelial tube formation capacity was evaluated by Matrigel assay. HRECs were seeded on Matrigel for 16 h and tube numbers were counted from 3 random visual fields. (d-A) HRECs with Ad-Ctrli, (d-B) HRECs with Ad-Nox4i, and (d-C) quantification results. versus Ctrli. Results represent 3 independent experiments. (e–g) Phosphorylation of VEGFR2 (e), ERK (f), and P38 (g) induced by VEGF (50 ng/mL) was determined by Western blot analysis and semiquantified by densitometry. ; versus Ctrli and or versus Ctrli with VEGF.

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