Eicosapentaenoic Acid Suppresses Ocular Inflammation in Endotoxin-Induced Uveitis

Abstract

Purpose: : Eicosapentaenoic acid (EPA), one representative of omega-3 polyunsaturated fatty acids, is clinically used in patients with hyperlipidemia to lower serum lipid levels. Recently, it has been reported that EPA may also provide anti-inflammatory effects in vivo. However, the effect of EPA in ocular inflammatory diseases still remains unclear. In this study, we investigate the therapeutic effect of EPA on ocular inflammation in endotoxin-induced uveitis (EIU) animals.

Methods: : C57/B6 mice (6 week-old male) were orally treated with EPA at the dose of 50mg/kg for 5 days. Subsequently, EIU was induced by intraperitoneal injection of 100µg LPS in the animals. Twenty-four hours after LPS injection, leukocyte adhesion to the retinal vasculature was evaluated with the concanavalin A lectin perfusion-labeling technique. Retinal protein levels of monocyte chemotactic protein (MCP)-1 were examined by Enzyme-Linked ImmunoSorbent Assay (ELISA).

Results: : At 24 hours after LPS injection, the EIU animals treated with oral EPA administration showed a significant decrease in leukocyte adhesion to the retinal vessels by 43.4% compared with vehicle-treated animals (182±42cells vs. 103±31cells, P <0.01). In addition, the EIU animals treated with EPA showed a significant decrease in retinal MCP-1 expression, which was upregulated by LPS treatment, by 48.2%.

Conclusions: : EPA suppressed leukocyte adhesion and MCP-1 levels in the retinal tissues of EIU model. These data suggest a therapeutic role of EPA in the treatment of ocular inflammatory diseases such as uveitis.

Keywords: eicosanoids • inflammation • uveitis-clinical/animal model