Functional Role of Novel Anthranilic Acid Derivatives as Anti-inflammatory Agents

Background: The discovery of new cyclooxygenase (COX) inhibitors with high efficacy and safety would greatly aid in developing anti-inflammatory drugs. This study evaluated the anti-inflammatory activity and the expected side effect of two synthesized anthranilic acid derivatives (JS-3 and JS-4). Materials and Methods: The COX selectivity of compounds was assessed in a whole blood assay. The results were confirmed by molecular docking studies. In vivo anti-inflammatory activity was tested in complete Freund’s adjuvant (CFA)-induced rheumatoid arthritis (RA) in rats. The safety profile was determined by administering a dose three times the therapeutic dose. Results: In vitro COX-2 selectivity of JS-4 was higher than JS-3 (13.70 vs. 5.56). Docking studies supported the higher selectivity of both derivatives against COX-2 than mefenamic acid. Treatment of CFA-arthritic rats with both compounds showed significant (P < 0.01) decreases in paw volume, paw thickness, arthritic index, and inflammatory parameters such as rheumatoid factor, interleukin (IL)-1β, IL-6, prostaglandin (PG) E₂, PGI₂, and TXB₂ compared to untreated RA animals. JS-3 and JS-4 improved knee joint histopathology and protected against RA-induced pathological changes: splenomegaly, thymomegaly, and cardiomyopathy. Both derivatives produced minimal effects on liver and renal functions, without any ulcerogenic effects. Conclusion: These results suggest that JS-4 is a potential and safe candidate for managing RA without renal, liver, gastrointestinal, or cardiovascular toxicity.