Differential Anti-Inflammatory Effects of Three Purified Omega Unsaturated Fatty Acids on Collagen-Induced Arthritis in Mouse

Abstract

Background: The Mediterranean Diet (MD) has been linked to a reduced risk of developing de-generative diseases, including atherosclerosis, heart stroke, diabetes, arthritis and cancer. However , only a few scientific investigations have attempted to validate this impression. The ingredients of the MD include significant amounts of omega (ω3, ω6, and ω9) unsaturated fatty acids (UFAs). A few studies of these UFAs in the prevention or treatment of arthritis have yielded controversial results, but a general belief regarding their beneficial effects has prevailed. Objective: To investigate the effects of three relevant UFAs, namely Docosahexaenoic Acid (DHA), Arachi-donic Acid (AA), and Oleic Acid (OA) (ω3, ω6, and ω9, respectively), in the development of arthritis using a murine model of Collagen-Induced Arthritis (CIA). Methods: DBA-1 mice were immunized with chicken collagen type II (CII) and were subsequently treated with ω-UFAs for 53 days. Dexa-methasone (DEXA) was used as a positive anti-inflammatory agent. The effect of the treatments was evaluated through several parameters: inflammation indices, antibody levels, cell proliferation , and histopathological findings. Results and Conclusion: The anti-inflammatory effect of the tested substances was inversely correlated with the histopathological findings: a greater anti-inflammatory effect was associated with less articular damage. Oleic acid (ω9) was the most efficient anti-inflammatory UFA, followed by DHA and then AA. DEXA completely inhibited the development of arthritis, whereas the untreated CII-immunized mice developed the most severe ar-ticular damage. DBA-1 mice with CII-induced arthritis constitute an adequate model for the study of arthritis and its treatment. P. I. Pérez-Martínez et al. 32