Suppression of laser-induced choroidal neovascularization by nontargeted siRNA.
PURPOSE. To investigate the effect of nontargeted siRNAs on vascular leakage and vascular endothelial growth factor (VEGF)-A expression in the development of choroidal neovascularization (CNV). METHODS. Nontargeted siRNAs were 21-nt (nucleotides) siRNA-Luc (Luciferase) or 16-nt siRNA-Luc. Targeted 21-nt siRNA-Vegfa or phosphate-buffered saline (PBS) was used for comparison. Laser photocoagulation was used to induce CNV in wild-type C57BL/6J mice; 7 days later, vascular leakage was determined by fluorescein angiography, and CNV volumes were measured by confocal microscopy. Expression of VEGF-A in the retinal pigment epithelium (RPE)/choroid was quantified by ELISA 3 days after photocoagulation. RESULTS. Pathologically significant leakage developed in most of the 16nt-siRNA-Luc- or PBS-injected mice but in significantly fewer 21nt-siRNA-Luc- and 21nt-siRNA-Vegfa-injected mice (P = 0.0004, P = 0.0001, respectively). CNV volume in 21-nt siRNA-Luc- and 21nt-siRNA-Vegfa-injected eyes was significantly lower than in PBS-injected eyes (P = 0.0124, P = 0.0040, respectively). CNV volume was not suppressed by 16-nt siRNA-Luc injection (P = 0.7700). The mean VEGF protein level decreased significantly in the 21nt-siRNA-Luc- and 21nt-siRNA-Vegfa-injected eyes compared with PBS-injected eyes 3 days after laser photocoagulation (P = 0.0011, P = 0.0063, respectively). The 16nt-siRNA-Luc-injected eyes did not show VEGF-A suppression 3 days after laser photocoagulation (P = 0.3177). Between 21-nt siRNA-Luc- and 21nt-siRNA-Vegfa-injected eyes, there were no significant differences in CNV volume, the VEGF-A level, or pathologic leakage detected by fluorescein. CONCLUSIONS. These data suggest that nontarget 21nt-siRNA can suppress laser-induced choroidal neovascularization anatomically and functionally through VEGF suppression.
Department of Ophthalmology and Visual Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Masayuki
M
Ashikari
Mayumi
M
Tokoro
Masahiro
M
Itaya
Miho
M
Nozaki
Yuichiro
Y
Ogura
D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects; D002829:Choroid / Q000098:blood supply / Q000378:metabolism; D020256:Choroidal Neovascularization / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D005451:Fluorescein Angiography; D017075:Laser Coagulation / Q000009:adverse effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000494:pharmacology*; D055213:Retinal Pigment Epithelium / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
D034741:RNA, Small Interfering; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse