Neuroprotective Effect of an Antioxidant Lutein in Light-Induced Retinal Degeneration

Abstract

Purpose: : To investigate the neuroprotective effect of lutein on retinal neural damage caused by photo-oxidative stress.

Methods: : Mice were fed with laboratory chow with or without 0.1% lutein and exposed to 5,000 lux fluorescent light for 3 hours. Retinal damage was estimated by analyzing (1) number of TUNEL positive cells, (2) outer nuclear layer (ONL) thickness, and (3) retinal function was measured by electroretinography (ERG).

Results: : Light exposure induced increase in TUNEL positive cells in ONL, leading to the reduction of ONL thickness and a-wave amplitude in ERG, as previously reported. (1) However, lutein diet decreased the light-induced apoptosis in ONL by 43.7% of the control (p<0.01). (2) Consistently, Lutein diet significantly avoided the reduction of ONL thickness (p<0.05). (3) Furthermore, mice fed with lutein diet showed higher level of a-wave amplitude in ERG than those fed with control chow after light exposure (p<0.01).

Conclusions: : Lutein contributed to preservation of better visual function by protecting photoreceptor cells from apoptosis after light exposure. Lutein has a neuroprotective effect in light-induced retinal degeneration.

Keywords: photoreceptors • antioxidants • neuroprotection