Clinical Ophthalmology (Dec 2018)
Periocular injection of candesartan-PLGA microparticles inhibits laser-induced experimental choroidal neovascularization
Abstract
Yoshitaka Okuda,1 Masanori Fukumoto,1 Taeko Horie,1 Hidehiro Oku,1 Shinji Takai,2 Toyofumi Nakanishi,3 Kaori Matsuzaki,4 Hiroyuki Tsujimoto,4 Tsunehiko Ikeda1 1Department of Ophthalmology, Osaka Medical College, Osaka, Japan; 2Department of Innovative Medicine, Graduate School of Medicine, Osaka Medical College, Osaka, Japan; 3Department of Clinical and Laboratory Medicine, Osaka Medical College, Osaka, Japan; 4Research and Development Division, Hosokawa Micron Corporation, Osaka, Japan 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. Keywords: age-related macular degeneration, choroidal neovascularization, renin-angiotensin system, candesartan, macrophage, monocyte chemotactic protein 1, poly(lactic-co-glycolic acid)