The Role of Withania somnifera (Ashwagandha) and Omega-3 Fatty Acids on TNF-α and Joint Inflammation in an Animal Model of Rheumatoid Arthritis

Abstract

Introduction: Rheumatoid Arthritis (RA) is an autoimmune disorder characterised by progressive joint destruction leading to severe disability. The existing management of RA includes Nonsteroidal Anti-Inflammatory Drugs (NSAIDs), DiseaseModifying Antirheumatic Drugs (DMARDs) and biological such as Tumour Necrosis Factor (TNF) inhibitors but search for alternative and safer therapy is still going on. Aim: To evaluate the efficacy of the combination of Withania somnifera (WS) and omega-3 fatty acids on TNF alpha level and joint histopathology in the treatment of Complete Freund’s Adjuvant (CFA) induced rheumatoid arthritis in a rat model. Materials and Methods: Healthy adult male Wistar albino rats were divided into six groups containing six rats in each group (n=36). Group I served as arthritis control, Group II and III received WS in dose of 500 mg/kg and 1000 mg/kg respectively. Group IV received Omega-3 polyunsaturated fatty acids in dose of 100 mg/kg. The combination of WS (1000 mg/kg) and Omega-3 polyunsaturated fatty acids (100 mg/kg) was given to rats of group V. Group VI served as standard treatment group and received Indomethacin 3 mg/kg. Arthritis was induced in groups II to VI by CFA. TNF-α was determined on day 0, 10 and 21. On day 21 all rats were sacrificed and inflamed limbs were excised above the ankle joints and examined for a pathological finding of RA. The data was analysed by one-way analysis of variance (ANOVA) followed by Dunnett’s test and Tukey test. The Dunnett’s test compares each mean to a control mean and simultaneous comparison between all other pairs was done by Tukey test. Results: WS in both doses showed significant reduction in TNF-α (p<0.001). Among all the treated groups, maximum mean percent TNF-α reduction in group VI (-65.65%) and minimum in group II (-37.35%) was found. Group V containing combination of WS and Omega-3 fatty acid showed a higher percent reduction in TNF-α and minimal cell infiltration as compared with groups II, III and IV. Conclusion: WS and omega-3 fatty acids suppress the changes produced due to adjuvant induced arthritis and combination of WS and omega-3 fatty acids was more effective than individual drugs alone.

Keywords

• autoimmune disorder
• complete freund’s adjuvant
• indomethacin