Xiaodi Zhou: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Xiaoxiao Xu: Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
Qiong Wang: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Yanting Lai: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Linyan Zhang: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Yunfeng Lin: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Department of Maxillofacial Surgery, West China Stomatological Hospital, Sichuan University, Chengdu, China.
Xiaoyan Ding: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Limei Sun: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Purpose: To assess the efficacy of tetrahedral framework nucleic acids (tFNAs) as a delivery system for small interfering RNA (siRNA) targeting RUNX1 (siRUNX1) in inhibiting retinal neovascularization (RNV) and restoring vascular integrity via the Dll4/Notch1 signaling pathway. Methods: tFNAs and tFNAs-siRUNX1 were synthesized using annealing of single-stranded DNAs and characterized by PAGE and high-performance capillary electrophoresis. Human umbilical vein endothelial cells were treated under hypoxic conditions with tFNAs-siRUNX1, and cellular uptake was evaluated using fluorescence microscopy and flow cytometry. Angiogenesis was assessed through EdU proliferation, tube formation, and wound-healing assays. In vivo experiments used oxygen-induced retinopathy (OIR) and laser-induced choroidal neovascularization (CNV) models in mice, with subsequent imaging by optical coherence tomography (OCT) and fundus fluorescence angiography. Gene and protein expression were analyzed by RT-PCR and Western blotting, focusing on the Dll4/Notch1 pathway and apoptosis markers. Results: tFNAs-siRUNX1 effectively inhibited endothelial cell proliferation, migration, and tube formation in vitro. In OIR and CNV models, it reduced neovascularization, nonperfusion areas, and vascular leakage. The mechanism involved modulation of the Dll4/Notch1 pathway, with decreased Dll4, Notch1, and Hes1 and increased Nts expression. tFNAs-siRUNX1 also reduced endothelial cell apoptosis via the Bcl-2/Bax pathway. Conclusions: tFNAs-siRUNX1 is a promising delivery system for targeting RNV, inhibiting neovascularization, and restoring retinal vascular integrity, providing a potential therapeutic alternative to anti-VEGF treatments.