INTRODUCTION: Although rheumatoid arthritis (RA) is primarily a chronic inflammatory autoimmune disease which affects the synovial joints, it has profound effects on bone remodeling characterized by increase osteoclastic activity, and a negative balance of bone formation and resorption. A strong correlation has been reported between RA and periodontitis with subsequent alveolar bone resorption. As a potent anti-inflammatory mediator, fish oil rich in omega-3 polyunsaturated fatty acids (n-3 PUFA) has demonstrated beneficial actions in various inflammatory conditions including RA and cardiovascular disease. High intakes of n-3 PUFA provide symptomatic relief and reduce the doses of anti-inflammatory drugs needed to control the RA symptoms.
OBJECTIVES: To evaluate the biological effect of fish oil on alveolar bone of rats with induced rheumatoid arthritis.
MATERIALS AND METHODS: Twenty one male albino rats were used in this study. The rats were divided into 3 groups 7 rats each. Group I: control group, Group II: RA induced group and Group III: RA induced group + fish oil. Rheumatoid arthritis induction was done by single subcutaneous injection of Freund's complete adjuvant. Fish oil was orally gavaged daily till the end of the experiment. Laboratory investigations were performed twice, after RA induction and at the end of the experiment. Effect of fish oil on alveolar bone of rats was assessed histologically and ultrastructurely in the different groups.
RESULTS: Remarkable improvement in the histology and the ultrastructure of the alveolar bone of rats in Group III was observed. Moreover, hematological values revealed significant decrease in the inflammatory condition of rats with induced RA after fish oil treatment.
CONCLUSION: Rheumatoid arthritis is an important risk factor for alveolar bone loss. The treatment of the RA induced rats with fish oil not only prevented the alveolar bone resorption and stimulated new bone formation, but also reduced relatively the level of rheumatoid factor in the blood.