Abstract
Purpose: :
Although the exact pathogenesis of age-related macular degeneration (AMD) is not clear, most studies indicate a role for retinal pigment epithelial cell damage and death caused by oxidative stress. The purpose of this study was to examine the potential protective effect of lutein, zeaxanthin, meclofenamic acid, and resveratrol on the acrolein-induced oxidative stress in human retinal pigment epithelial (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 µM), zeaxanthin (100 µM), meclofenamic acid (30 µM), and resveratrol (10 µM) were investigated by pretreatment with the above agents before toxicant exposure in acute toxicity models and co-treatment with the toxicant in chronic toxicity models. The synergistic effects of hyperoxide 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/hyperoxide toxicity model. Co-treatment with lutein, zeaxanthin, meclofenamic acid, or resveratrol showed a protective effect against the damage caused by 7-day acrolein exposure followed by hyperoxide 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 prevent smoking-induced or age-related RPE degeneration, such as AMD.
Keywords: retinal pigment epithelium • oxidation/oxidative or free radical damage • phagocytosis and killing