title: [Targeting VEGF siRNA transfection by new polymeric liposomes to inhibit retinal neovascularization].
abstract: OBJECTIVE
  To formulate and evaluate polymeric liposomes (PL) nanoparticles as a novel non-viral gene delivery. To explore its applicability and feasibility as a non-viral vector for gene transportation.
  
  
  METHODS
  Experimental study. To construct the orongoxygen induced retinopathy (OIR) mouse (C57BL/6J) model on the basis of improved Smith's methods. Western blot was used to measure VEGF protein expression in retinal tissue at P17 and P22. HE staining and fluorescein-dextran angiography of retinal vascular were performed to observe the morphologic alterations of retinal neovascularization. Frozen-section was used to show the membrane translocation of PL.
  
  
  RESULTS
  In fluorescence angiograms, irregular neovascularization and fluoresce leakage were observed in OIR model. The results of Western blot showed that VEGF protein in retinal tissues were significantly different among groups (F = 158.207, P = 0.000) at P17 and P22 (F = 25.695, P = 0.000). The protein level was lower in both PL (0.70 ± 0.03) and Lipo group (0.66 ± 0.04) at P17 (P = 0.092), and the lower level was presented at P22 in PL group (0.50 ± 0.03) than in Lipo group (0.53 ± 0.05) (P < 0.05). HE staining were performed to observe the significantly improvements of retinal neovascularization in PL (28.0 ± 3.44) and Lipo group (24.50 ± 3.06) at P17. Moreover, inhibitory effects maintained at P22 in PL group (11.70 ± 3.09) as HE staining showed. Fluorescein angiography of retinal vascular showed retinal non-perfusion and neovascularization areas were smaller in both PL and Lipo group at P17. Frozen-section examination showed the property of membrane translocation. GFP expression could be seen in vitreous cavity just at first day post-intravitreal administration in PL and Lipo group, which could reach their peaks in external retina nearby RPE layer at P17, remaining at P22 in PL group.
  
  
  CONCLUSIONS
  The PL performed excellent ability of membrane translocation and it was a kind of slow steady released gene vector.
authors: Department of Ophthalmology, Shanxi Eye Hospital, Taiyuan 030002, China.
authors: Yan
authors: Y
authors: Gao
authors: Xinling
authors: X
authors: Liu
authors: Chunhui
authors: C
authors: Li
authors: Yao
authors: Y
authors: Peng
authors: Jizhong
authors: J
authors: Yang
authors: Xiaowu
authors: X
authors: Wang
authors: Email: xiaorli@163.com.
authors: Xiaorong
authors: X
authors: Li
mesh_terms: D000818:Animals; D003911:Dextrans; D005240:Feasibility Studies; D005451:Fluorescein Angiography; D005452:Fluoresceins; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D008081:Liposomes / Q000008:administration & dosage / Q000493:pharmacokinetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D053758:Nanoparticles / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism*; D012160:Retina / Q000378:metabolism*; D015861:Retinal Neovascularization / Q000378:metabolism* / Q000473:pathology; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D003911:Dextrans; D005452:Fluoresceins; D008081:Liposomes; D034741:RNA, Small Interfering; D042461:Vascular Endothelial Growth Factor A; C052526:fluorescein-dextran