Effect of lutein in olive oil in the mouse oxygen-induced retinopathy model

Abstract

Purpose : Retinopathy of prematurity (ROP), a proliferative retinopathy in preterm babies, is an oxidative stress associated disease. Lutein as anti-oxidative agent is a potential therapeutic agent for ROP. To improve the bioavailability of lutein, olive oil was used to dissolve lutein. To investigating the effect of lutein in olive oil in ROP progression, retinal vasculature and function were examined in mouse oxygen-induced retinopathy (OIR) model. Methods : C57Bl/6J mother and their pups were placed into 75% oxygen chamber from postnatal day (P) 7 to P12. DMSO, olive oil alone, lutein in DMSO or lutein in olive oil (0.2mg/kg) were intraperitoneally injected into the pups starting from P12 daily. Retinal vasculature was examined in isolectin-stained retinal flat mounts at P14 and P17. Retinal function was assessed at P17 using scotopic electroretinography (ERG). Results : Olive oil alone, lutein in DMSO and lutein in olive oil did not affect the body weight under normal room air (RA) condition or after OIR at P14 and 17. Under normal RA, the pups receiving lutein in DMSO have higher a-wave and b-wave amplitudes at P17 without affecting the normal retinal vascular development when compared with DMSO, olive oil alone or lutein in olive oil treated group. After OIR, olive oil or lutein in olive oil treated groups have a larger avascular area (DMSO: 26.4±2.9%; olive oil: 32.3±2.6%; lutein in DMSO: 26.2±2.7%; lutein in olive oil: 32.4±3.4%). At P17, although no significant difference was observed in the size of neovascularization, olive oil alone, lutein in DMSO and lutein in olive oil treated pups have a larger avascular area (DMSO: 13.5± 2.8%; olive oil: 17.3±7.2%; lutein in DMSO: 18.1±1.6%; lutein in olive oil: 16.6±5.0%). Most importantly, lutein in olive oil treated pups have higher a-wave and b-wave amplitudes with shorter implicit times. Conclusions : Lutein in olive oil treated pups displayed an improvement of retinal function including the function of photoreceptors, bipolar cells and Müller cells after OIR, suggesting that lutein in olive oil may preserve retinal function after OIR despite limited effects in vascular protection.