Resveratrol Protects Human Retinal Pigment Epithelial Cells from Acrolein-Induced Damage

PURPOSE: Although the exact pathogenesis of age-related macular degeneration (AMD) is not clear, most studies indicate a role for retinal pigment epithelial (RPE) cell damage and death caused by oxidative stress. The purpose of this study was to examine the potential protective effects of lutein, zeaxanthin, meclofenamic acid, and resveratrol on the acrolein-induced oxidative stress in human RPE cells. METHODS: Cultured human RPE R-50 cells were treated with acrolein at different concentrations and treatment times. The protective effects of lutein (100 microM), zeaxanthin (100 microM), meclofenamic acid (30 microM), and resveratrol (10 microM) were investigated by pretreatment with the above agents before toxicant exposure in acute toxicity models and cotreatment with the toxicant in chronic toxicity models. The synergistic effects of acrolein and hydrogen peroxide exposure were also studied. Fluorescent latex beads were used to assess the phagocytic function of the cells. RESULTS: Acrolein inhibited the phagocytic function of human RPE R-50 cells, and the inhibitory effects were time dependent. Pretreatment with lutein, zeaxanthin, meclofenamic acid, or resveratrol alleviated the inhibition of phagocytosis in the acute acrolein and combined acrolein/hydrogen peroxide toxicity models. Synergistic effects were seen between zeaxanthin and resveratrol or meclofenamic acid. Cotreatment with lutein, zeaxanthin, meclofenamic acid, or resveratrol showed a protective effect against the damage caused by 7-day acrolein exposure followed by hydrogen peroxide treatment. CONCLUSIONS: Our results indicated an inhibitory effect of compounds found in cigarette smoke on human RPE phagocytosis, and lutein, zeaxanthin, meclofenamic acid, and resveratrol each offered protection against this inhibition. Therefore, red wine polyphenol, resveratrol, might ameliorate acrolein-induced or age-related RPE degeneration, such as AMD.