Periocular injection of candesartan-PLGA microparticles inhibits laser-induced experimental choroidal neovascularization

PURPOSE: Microparticle technology enables local administration of medication. The purpose of this study was to examine the inhibitory effect of locally administered candesartan (CAN)-encapsulated microparticles on experimental choroidal neovascularization (CNV). METHODS: Laser photocoagulation was used to induce CNV in Brown Norway rats. The rats were pretreated with subconjunctival injections of CAN (5.0 mg/eye) or phosphate buffer saline for 3 days before photocoagulation. The volume of CNV was evaluated 7 days after laser injury using the lectin staining technique. The infiltration of macrophages within the CNV lesion was determined using immunofluorescent staining with an anti-CD68 antibody. mRNA levels of MCP-1, IL1-β and VEGF in the retinal pigment epithelium/choroid complex were determined using quantitative PCR (q-PCR). RESULTS: CNV volume was significantly suppressed by the treatment with CAN compared with that in vehicle-treated eyes (P<0.05, two-tailed Student’s t-test). Subconjunctival injections of CAN decreased the numbers of CD68(+) cells in the CNV lesion. The increased mRNA levels of MCP-1, IL1-β, and VEGF induced by photocoagulation was significantly suppressed following the local administration of CAN (P<0.05, two-tailed Student’s t-test). CONCLUSION: Local administration of CAN inhibited experimentally induced CNV possibly through anti-inflammatory effects.