Pathologic ocular neovascularization commonly causes blindness. It is critical to identify the factors altered in pathologically proliferating versus normally quiescent vessels to develop effective targeted therapeutics. MicroRNAs regulate both physiological and pathological angiogenesis through modulating expression of gene targets at the posttranscriptional level. However, it is not completely understood if specific microRNAs are altered in pathologic ocular blood vessels, influencing vascular eye diseases. Here we investigated the potential role of a specific microRNA, miR-150, in regulating ocular neovascularization. We found that miR-150 was highly expressed in normal quiescent retinal blood vessels and significantly suppressed in pathologic neovessels in a mouse model of oxygen-induced proliferative retinopathy. MiR-150 substantially decreased endothelial cell function including cell proliferation, migration, and tubular formation and specifically suppressed the expression of multiple angiogenic regulators, CXCR4, DLL4, and FZD4, in endothelial cells. Intravitreal injection of miR-150 mimic significantly decreased pathologic retinal neovascularization in vivo in both wild-type and miR-150 knockout mice. Loss of miR-150 significantly promoted angiogenesis in aortic rings and choroidal explants ex vivo and laser-induced choroidal neovascularization in vivo. In conclusion, miR-150 is specifically enriched in quiescent normal vessels and functions as an endothelium-specific endogenous inhibitor of pathologic ocular neovascularization.neovascularization | endothelial cells | microRNA | miR-150 | retinopathy

Our findings suggest that increasing APN by ω-3 LCPUFA supplementation in total parental nutrition for preterm infants may suppress ROP.

The mouse model of laser-induced choroidal neovascularization (CNV) has been used in studies of the exudative form of age-related macular degeneration using both the conventional slit lamp and a new image-guided laser system. A standardized protocol is needed for consistent results using this model, which has been lacking. We optimized details of laser-induced CNV using the image-guided laser photocoagulation system. Four lesions with similar size were consistently applied per eye at approximately double the disc diameter away from the optic nerve, using different laser power levels, and mice of various ages and genders. After 7 days, the mice were sacrificed and retinal pigment epithelium/choroid/sclera was flat-mounted, stained with Isolectin B4, and imaged. Quantification of the area of the laser-induced lesions was performed using an established and constant threshold. Exclusion criteria are described that were necessary for reliable data analysis of the laser-induced CNV lesions. The CNV lesion area was proportional to the laser power levels. Mice at 12-16 weeks of age developed more severe CNV than those at 6-8 weeks of age, and the gender difference was only significant in mice at 12-16 weeks of age, but not in those at 6-8 weeks of age. Dietary intake of omega-3 long-chain polyunsaturated fatty acid reduced laser-induced CNV in mice. Taken together, laser-induced CNV lesions can be easily and consistently applied using the image-guided laser platform. Mice at 6-8 weeks of age are ideal for the laser-induced CNV model.