MicroRNA-34a attenuates VEGF-mediated retinal angiogenesis via targeting Notch1.
Pathological angiogenesis in the retina is one of the main ocular diseases closely associated with vision loss. This work investigated the roles of microRNA-34a (miR-34a) and its potential target Notch1, in retinal angiogenesis. For this we used oxygen-induced retinopathy (OIR) rats and human retinal microvascular endothelial cells (HRMECs) stimulated with vascular endothelial growth factor (VEGF). We performed hematoxylin-eosin staining, Western blot for VEGF, and immunofluorescence staining for CD31 to verify the establishment of our OIR model. We observed down-regulation of miR-34a, and up-regulation of Notch1 and Hey1 in retinas from OIR rats. We found similar results with the VEGF-stimulated HRMECs. By performing MTT assay, cell scratch assay, tube formation assay, and by detecting the expression of matrix-metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitors of metalloproteinases-1 (TIMP-1), and TIMP-2, we found that transfection of miR-34a ameliorated VEGF-mediated angiogenesis of HRMECs. We further observed that siRNA-induced gene silencing of Notch1 prevented VEGF-induced angiogenesis via regulating cell proliferation, cell migration, and tube formation of HRMECs. Additionally, activation of Notch1 by transfection of Notch1 plasmid attenuated the inhibitory effects of miR-34a on tube formation, in the present of VEGF. Results from our dual-luciferase reporter gene assay suggested that miR-34a targets Notch1. In summary, our data demonstrate that miR-34a attenuates retinal angiogenesis via targeting Notch1.
['Shi|Shaoyang|S|', 'Jin|Yong|Y|', 'Song|Haishan|H|', 'Chen|Xiaolong|X|']
D000818:Animals D002465:Cell Movement D049109:Cell Proliferation D020868:Gene Silencing D006801:Humans D035683:MicroRNAs D034741:RNA, Small Interfering D051381:Rats D017207:Rats, Sprague-Dawley D051881:Receptor, Notch1 D015861:Retinal Neovascularization D042442:Vascular Endothelial Growth Factors
retinal angiogenesis Notch1 miR-34a OIR VEGF RIO angiogenèse rétinienne