The Effect of Long Chain N-3 Polyunsaturated Fatty Acids on Development of Collagen-induced Arthritis in Rats

Abstract

Background: The treatment of rheumatoid arthritis still depend on conserve therapy in major. Recent studies report that n-3 polyunsaturated fatty acids(PUFA) could modulate the incidence and progress of arthritis. The purpose of this study was to investigate the effects of n-3 PUFA on the development of collagen-induced arthritis in rats. Materials and Methods: Female Louvain rats were used for this experiment. Rats were randomly assigned into either normal (n=8) or collagen-immunized groups, and collagen immunized groups were divided into control(n=8, normal diet) and n-3 PUFA(n=8, 5% n-3 PUFA in diet) groups. One week after feeding n-3 PUFA to rats, they were immunized with type II collagen emulsified in incomplete Freund's adjuvant into tail and back. Development of arthritis was confirmed by x-ray and microscopic examination. Results: Incidence of arthritis at the 5th week after immunization was 38% in control and 0% in n-3 PUFA. Rats with arthritis showed edema in hind paws and inflammation in synovial membrane of the knee joint. Plasma glucose and insulin were not changed by both of immunization and diet. Plasma triglycerides and cholesterol concentrations were decreased by n-3 PUFA. Conclusion: n-3 PUFA may prevent or treat collagen-induced arthritis m rats. Further studies are needed for action mechanism of it.