title: Hypoxia-induced retinal neovascularization in zebrafish embryos: a potential model of retinopathy of prematurity.
abstract: Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2-4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression.
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Wu
authors.affiliation: Department of Chemistry, Tamkang University, Tamsui, New Taipei City, Taiwan.
authors.forename: Chao-Yuan
authors.initials: CY
authors.lastname: Chang
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Alex
authors.initials: A
authors.lastname: Kao
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Brian
authors.initials: B
authors.lastname: Hsi
authors.affiliation: Department of Ophthalmology, Cathay General Hospital, Taipei, Taiwan.
authors.forename: Shwu-Huey
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Chemistry, Tamkang University, Tamsui, New Taipei City, Taiwan.
authors.forename: Yau-Hung
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: I-Jong
authors.initials: IJ
authors.lastname: Wang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology; D000860:Hypoxia / Q000473:pathology*; D007814:Larva / Q000378:metabolism; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000378:metabolism; D012160:Retina / Q000378:metabolism / Q000473:pathology*; D015861:Retinal Neovascularization / Q000378:metabolism / Q000473:pathology*; D012171:Retinal Vessels / Q000378:metabolism / Q000473:pathology; D012178:Retinopathy of Prematurity / Q000378:metabolism / Q000473:pathology*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D015027:Zebrafish
chemical_list: D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A