title: Inhibition of retinal neovascularization by siRNA targeting VEGF(165).
abstract: OBJECTIVE
  To investigate whether vector-based vascular endothelial growth factor 165 (VEGF)(165) targeted siRNA expression system (pSilencer(siVEGF)) could inhibit VEGF(165) expression in vitro and suppresses retinal neovascularization in the murine model of oxygen-induced retinopathy.
  
  
  METHODS
  pSilencer(siVEGF), from which siRNA targeting VEGF(165) could be generated, was constructed and transfected to human umbilical vein endothelial cells. Then the level of VEGF isoforms in cultured cells was measured by RT-PCR and ELISA. Intravitreal injection of pSilencer(siVEGF) was performed in mice with ischemic retinopathy. Retinal neovascularization was evaluated by angiography using fluorescein-labeled dextran and quantitated histologically. The levels of VEGF(164), which is equivalent to human VEGF(165) in murine retinas were determined by RT-PCR and western immunoblotting.
  
  
  RESULTS
  Expression of VEGF(165) in cultured cells was greatly curtailed by pSilencer(siVEGF) under both normoxia and hypoxia conditions. However, the other isoforms, VEGF(189) and VEGF(121), were expressed to a similar degree regardless of whether pSilencer(siVEGF) was administered. Based on angiography and histological analysis, retinal neovascularization in the eyes treated with pSilencer(siVEGF) were significantly reduced compared to the control eyes. Furthermore, the VEGF(164) levels in the murine retinas were suppressed by pSilencer(siVEGF).
  
  
  CONCLUSIONS
  Retinal neovascularization in the murine model was significantly attenuated by pSilencer(siVEGF) through decreasing VEGF(164) levels in the retinas. pSilencer(siVEGF) seems to be a potential therapeutic tool for ischemic-induced retinal diseases.
authors.affiliation: Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China. xbxia@yahoo.com
authors.forename: Xiao-bo
authors.initials: XB
authors.lastname: Xia
authors.forename: Si-qi
authors.initials: SQ
authors.lastname: Xiong
authors.forename: Wei-tao
authors.initials: WT
authors.lastname: Song
authors.forename: Jie
authors.initials: J
authors.lastname: Luo
authors.forename: Yu-ke
authors.initials: YK
authors.lastname: Wang
authors.forename: Rong-rong
authors.initials: RR
authors.lastname: Zhou
mesh_terms: D000792:Angiography; D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D004195:Disease Models, Animal; D006801:Humans; D051379:Mice; D034741:RNA, Small Interfering / Q000378:metabolism*; D012160:Retina / Q000378:metabolism / Q000473:pathology; D015861:Retinal Neovascularization / Q000473:pathology*; D042461:Vascular Endothelial Growth Factor A / Q000172:deficiency* / Q000378:metabolism
chemical_list: D034741:RNA, Small Interfering; D042461:Vascular Endothelial Growth Factor A