Implication of the hypoxia response element of the vegf promoter in mouse models of retinal and choroidal neovascularization, but not retinal vascular development
2005; Wiley; Volume: 206; Issue: 3 Linguagem: Inglês
10.1002/jcp.20525
ISSN1097-4652
AutoresStanley A. Vinores, Wei‐Hong Xiao, Sadia Aslam, Jikui Shen, Yuji Oshima, Hiroyuki Nambu, Hansheng Liu, Peter Carmeliet, Peter A. Campochiaro,
Tópico(s)Retinal Development and Disorders
ResumoAbstract Retinal neovascularization (NV) and macular edema, resulting from blood‐retinal barrier (BRB) breakdown, are major causes of visual loss in ischemic retinopathies. Choroidal NV (CNV) occurs in diseases of the retinal pigmented epithelium/Bruch's membrane complex and is another extremely prevalent cause of visual loss. We used mice in which the hypoxia response element (HRE) is deleted from the vascular endothelial growth factor ( vegf ) promoter (Vegf δ/δ mice) to explore the role of induction of VEGF through the HRE in these disease processes. Compared to wild type (Vegf +/+ ) mice with oxygen‐induced ischemic retinopathy (OIR) in which vegf mRNA levels were increased and prominent retinal NV and BRB breakdown occurred, Vegf δ/δ littermates with OIR failed to increase vegf mRNA levels in the retina and had significantly less retinal NV and BRB breakdown, but showed prominent dilation of some superficial retinal vessels. Vegf +/δ littermates with ischemic retinopathy developed comparable retinal NV to Vegf +/+ mice, exhibited intermediate levels of BRB breakdown, and did not show vasodilation. In a mouse model of CNV, due to laser‐induced rupture of Bruch's membrane, the area of CNV at Bruch's membrane rupture sites was more than tenfold greater in Vegf +/+ mice than in Vegf δ/δ littermates. In contrast to these dramatic differences in pathologic ocular NV, Vegf δ/δ mice showed subtle differences in retinal vascular development compared to Vegf +/+ mice; it was slightly delayed, but otherwise normal. These data suggest that induction of VEGF through the HRE in its promoter is critical for retinal and CNV, but not for retinal vascular development. J.Cell.Physiol. © 2005 Wiley‐Liss, Inc.
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