EFFECT OF DIETARY LIPIDS ON ADJUVANT-INDUCED ARTHRITIS IN RATS

Young (4 week old), female Lewis rats were fed semipurified diets containing 7.5% lipid as either beef tallow or corn oil in one study, or 5% lipid as either olive oil, corn oil or fish oil in a second study. The lipids in these diets were chosen for their differences in fatty acid profiles that can lead to alterations in the types and amount of bioactive eicosanoids produced from them. After 4 weeks of feeding the respective diets, rats were injected with complete Freund's adjuvant to induce inflammation. In the first study corn oil fed rats showed earlier onset of inflammation and significantly greater arthritic index compared to beef fat fed rats. In the second study corn oil and olive oil fed rats had significantly greater arthritic scores than fish oil fed rats. These results suggest that the omega-6 polyunsaturated fatty acids in the corn oil and olive oil diets may exacerbate adjuvant-induced arthritis. © 1990 Pergamon Press plc.