Wang Jiaojiao, Zhou Chunhong, Zhuang Kai, Zou Jiami, Qiu Wanlu, Jin Mei, Ye Weile, Yang Pinglian, Zheng Zhihua, Zhou Qing, Huang Zunnan, Wang Yuanxiang, Liu Peiqing, Lu Jing, Huo Yuqing, Liu Zhiping
State Key Laboratory of Bioactive Molecules and Druggability Assessment, Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drugs Research, International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education of China, College of Pharmacy, Jinan University, Guangzhou 511436, China.
Key Laboratory of Big Data Mining and Precision Drug Design of Guangdong Medical University, Key Laboratory of Computer-Aided Drug Design of Dongguan City, Key Laboratory for Research and Development of Natural Drugs of Guangdong Province, School of Pharmacy, Guangdong Medical University, Dongguan 523808, China.
Proc Natl Acad Sci U S A. 2025 Sep 16;122(37):e2426578122. doi: 10.1073/pnas.2426578122. Epub 2025 Sep 9.
Proliferative retinopathy is a leading cause of irreversible blindness in humans; however, the molecular mechanisms behind the immune cell-mediated retinal angiogenesis remain poorly elucidated. Here, using single-cell RNA sequencing in an oxygen-induced retinopathy (OIR) model, we identified an enrichment of sorting nexin (SNX)-related pathways, with SNX3, a member of the SNX family that is involved in endosomal sorting and trafficking, being significantly upregulated in the myeloid cell subpopulations of OIR retinas. Immunostaining showed that SNX3 expression is markedly increased in the retinal microglia/macrophages of mice with OIR, which is mainly located within and around the neovascular tufts. Myeloid cell-specific deficiency of inhibited retinal neovascularization, hyperpermeability, and dysfunction in OIR mice. Using glutathione S-transferase pull-down, coimmunoprecipitation, and immunofluorescent staining, we found that SNX3 interacted with receptor-interacting protein 1/3 (RIP1 and RIP3). We further demonstrated that RIP1/3 degradation was accelerated in SNX3-deleted microglia/macrophages, causing an inhibition of hypoxia-induced necroptosis and mitochondrial fission, thereby decreasing the production of proinflammatory and proangiogenic factors (FGF2 and MMP12). Moreover, OIR retinas from myeloid cell-specific SNX3 overexpression transgenic mice presented more angiogenic tufts, while RIP1/3 inhibition largely ablated SNX3 overexpression-induced pathological angiogenesis. Based on the structure of SNX3, we identified a small-molecule inhibitor, W1122. Intriguingly, we found that W1122 effectively inhibited retinal angiogenesis in the OIR model, and combination treatment with anti-Vascular Endothelial Growth Factor (VEGF) yielded enhanced antiangiogenic effects. Collectively, our findings disclose a link between SNX3 and RIP1/3 signaling and implicate SNX3 in the development of ischemic retinopathy.
增殖性视网膜病变是人类不可逆性失明的主要原因；然而，免疫细胞介导的视网膜血管生成背后的分子机制仍未得到充分阐明。在此，我们利用氧诱导性视网膜病变（OIR）模型进行单细胞RNA测序，发现分选连接蛋白（SNX）相关通路富集，其中参与内体分选和运输的SNX家族成员SNX3在OIR视网膜的髓样细胞亚群中显著上调。免疫染色显示，OIR小鼠视网膜小胶质细胞/巨噬细胞中SNX3表达明显增加，主要位于新生血管簇内及其周围。髓样细胞特异性缺失SNX3可抑制OIR小鼠的视网膜新生血管形成、高通透性和功能障碍。通过谷胱甘肽S-转移酶下拉实验、免疫共沉淀和免疫荧光染色，我们发现SNX3与受体相互作用蛋白1/3（RIP1和RIP3）相互作用。我们进一步证明，在缺失SNX3的小胶质细胞/巨噬细胞中，RIP1/3的降解加速，导致缺氧诱导的坏死性凋亡和线粒体裂变受到抑制，从而减少促炎和促血管生成因子（FGF2和MMP12）的产生。此外，髓样细胞特异性过表达SNX3的转基因小鼠的OIR视网膜出现更多的血管生成簇，而抑制RIP1/3可在很大程度上消除SNX3过表达诱导的病理性血管生成。基于SNX3的结构，我们鉴定出一种小分子抑制剂W1122。有趣的是，我们发现W1122在OIR模型中有效抑制视网膜血管生成，与抗血管内皮生长因子（VEGF）联合治疗可增强抗血管生成作用。总的来说，我们的研究结果揭示了SNX3与RIP1/3信号之间的联系，并表明SNX3参与缺血性视网膜病变的发展。
