Abstract
This study evaluated the protective effect of different dietary omega-6/omega-3 ratios in oils obtained from various nuts (walnut, peanut, cashew, and hazelnut) against morphological features and markers of inflammation on an adjuvant-induced arthritis rat model. Rheumatoid arthritis (RA) was induced via intradermal injection of heat-killed Mycobacterium tuberculosis. Five groups of rats with RA (n = 5) were randomly categorized as follows: control positive, walnut oil group, peanut oil group, cashew nut oil group, and hazelnut oil group. Another five healthy rats served as a normal non-arthritic (control) group. We assessed the therapeutic effects by measuring arthritis scores during the experiment and serum inflammatory markers at the end of the study. The serum levels of the rheumatoid factor, TNF-alpha, IL-6, IL-1 beta, and PGE2, were significantly (p <= 0.05) reduced in all treatment groups. The daily consumption of nut oils ameliorates clinical and morphological abnormalities by inhibiting the inflammatory cells that produce inflammatory interleukins and eicosanoids.