OTX008 inhibits retinal neovascularization in oxygen-induced retinopathy mice / 中华眼底病杂志

ABSTRACT

Objective To investigate the inhibitory effects and possible related mechanism of OTX008 [a selective inhibitor of galectin-1 (Galectin-1)] on retinal neovascularization (RNV) in mouse model of oxygeninduced retinopathy (OIR).Methods 7-day-old (P7) C57BL/6J mice were randomly (according to random number table) divided into 4 groups including normal group,OIR group,OIR-OTX008 group and OIRphosphate buffered saline (PBS) group.To establish the OIR mouse model,mice from all groups except normal group were expose to (75±2)％ oxygen for 5 days and then to room air.OIR-OTX008 group received an intravitreal injection of 1 μl (0.25 μg/μl) OTX008 at P12,OIR-PBS group received the equal volume (1 μl) of PBS injection.Mice from 4 groups were euthanized at P17,and retinas were collected for molecular biological analysis and morphological study.RNV was evaluated by counting the number ofpre-retinal neovascular nuclei and the whole-mount immunofluorescent staining of mouse retina.Cyrosections of retinas were imaged via confocal microscopy to observe the enrichment of staining of Galectin-1.Protein levels of Galectin-1,Neuropilin-1 and phosphorylation of vascular endothelial growth factor receptor 2 (pVEGFR2) were determined with Western blot.Results At P17,Galectin-1 expressed higher in retinal ganglion cell layer,inner plexiform layer and inner nuclear layer from OIR group and OIR-PBS group than normal group.Galectin-1 expressed less in cryosection retinas from OIR-OTX008 group than OIR group and OIR-PBS group.The numbers ofpre-retinal neovascular cell nuclei from OIR group and OIR-pBS group were obviously more than that from normal group (t=9.314,P＜0.05).The number of pre-retinal neovascular cell nuclei from OIR-OTX008 group were obviously lower than those from OIR group and OIR-PBS group (t=8.038,7.774;P＜0.05).The RNV tufts area (t=13.250,12.570),non-perfusion area (t=15.590,12.430) and hypoxic area (t=9.542,9.928) from OIR-OTX008 group were significantly smaller than those in OIR group and OIR-PBS group (P＜ 0.05).Protein levels of Galectin-1 (t=24.800,23.060),Neuropilin-1 (t=4.120,3.530) and pVEGFR2 (t=25.880,15.480) in the OIR-OTX008 group were significantly down-regulated than those from OIR group and OIR-PBS group (P＜0.05).Conclusion Intravitreal injection of OTX008 inhibits RNV and ameliorates retinal hypoxia in mice model of OIR possibly through down-regulating Galectin-1,Neurolinpin-1 and pVEGFR2.