Liao Yujun, Yu Chunhong, Xiong Weiwei, Yin Xiaolong
The Second Affiliated Hospital of Nanchang University, No.1 Minde Road, Nanchang, 330006, Jiangxi, China.
Hum Cell. 2025 Aug 8;38(5):140. doi: 10.1007/s13577-025-01270-3.
Retinopathy of prematurity (ROP) is an abnormal proliferative disease of retinal blood vessels. This study investigates the role of Robo4 in angiogenesis and its molecular mechanisms in the Oxygen-Induced Retinopathy (OIR) model and a hypoxic injury model of human umbilical vein endothelial cells (HUVECs). In the OIR model, Roundabout 4 (Robo4) expression was significantly decreased, while Robo4 overexpression inhibited neovascularization and alleviated retinal tissue damage. Under hypoxic injury-inducing conditions in HUVECs, Robo4 expression was inhibited, but overexpression enhanced cell proliferation and inhibited angiogenesis by negatively regulating the expression of adenosine diphosphate ribosylation factor 6 (ARF6) and vascular endothelial growth factor (VEGF). Molecular analysis revealed that Robo4 regulates VEGF expression through ARF6. Overexpression of Robo4 reduced ARF6 and VEGF expression, while knocking down Robo4 increased ARF6 and VEGF levels, confirming Robo4's role as a key regulator in the ARF6-VEGF axis. Additionally, Robo4 overexpression significantly inhibited the angiogenic capacity of HUVECs, and ARF6 overexpression partially reversed Robo4-mediated inhibition of angiogenesis. In the OIR model, Robo4 overexpression significantly suppressed pathological neovascularization, as evidenced by a significant reduction in the percentage of non-perfused areas. Furthermore, Robo4 overexpression downregulated ARF6 and VEGF expression levels and promoted the normalization and remodeling of retinal vascular structures. These findings suggest that Robo4 inhibits pathological angiogenesis by regulating ARF6 and VEGF, providing insights into its potential as a therapeutic target for retinal diseases like ROP.
早产儿视网膜病变（ROP）是一种视网膜血管的异常增殖性疾病。本研究在氧诱导性视网膜病变（OIR）模型和人脐静脉内皮细胞（HUVECs）缺氧损伤模型中，研究了Robo4在血管生成中的作用及其分子机制。在OIR模型中，Roundabout 4（Robo4）表达显著降低，而Robo4过表达抑制新生血管形成并减轻视网膜组织损伤。在HUVECs缺氧损伤诱导条件下，Robo4表达受到抑制，但过表达通过负调控二磷酸腺苷核糖基化因子6（ARF6）和血管内皮生长因子（VEGF）的表达来增强细胞增殖并抑制血管生成。分子分析表明，Robo4通过ARF6调节VEGF表达。Robo4过表达降低了ARF6和VEGF表达，而敲低Robo4则增加了ARF6和VEGF水平），证实了Robo4在ARF6-VEGF轴中作为关键调节因子的作用。此外，Robo4过表达显著抑制了HUVECs的血管生成能力，而ARF6过表达部分逆转了Robo4介导的血管生成抑制。在OIR模型中，Robo4过表达显著抑制病理性新生血管形成，非灌注区域百分比显著降低证明了这一点。此外，Robo4过表达下调了ARF6和VEGF表达水平，并促进了视网膜血管结构的正常化和重塑。这些发现表明，Robo4通过调节ARF6和VEGF抑制病理性血管生成，为其作为ROP等视网膜疾病治疗靶点的潜力提供了见解。
