Therapeutic and Protective Efficacy of Esculetin on Inflammation and Cartilage Injury by Monosodium Iodoacetate-Induced Osteoarthritis in a Sprague-Dawley Rat Model

Background: Osteoarthritis (OA) is a major bone-related disease, which is characterized by joint deterioration, bone destruction, and whole joint damage, leading to permanent disability. The present study aimed to assess the anti-inflammatory and anti-osteoarthritic effects of esculetin in a monosodium iodoacetate (MI)-induced OA model in Sprague-Dawley (SD) rats. Materials and Methods: The anti-osteoarthritic efficacy of esculetin was determined in an MI-induced OA animal model. Rats were divided into the following groups: group I: normal control (saline), group II (MI only treated), group III (MI + esculetin), and group IV (MI + indomethacin). The potent outcome of esculetin treatment was assessed through its effects on the proinflammatory cytokines' levels, weight-bearing distribution, and histopathologic observation. Anti-inflammation efficacy of esculetin was evaluated in lipopolysaccharide (LPS)-induced Ralph and William's cell line 264.7 (RAW 264.7) cells. Results: In vitro results showed that esculetin has an anti-inflammatory efficacy through lessening the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, and IL-6 in LPS-induced RAW cells. Furthermore, esculetin also reinforced the retrieval of hind limb weight-holdingcapacity, downregulated the generation of inflammatory mediators and proinflammatory cytokines, and shielded or protected the cartilage tissue from damage in the OA model SD rats. Conclusion: Esculetin seems to be a beneficial therapeutic compound for handling OA and OA-based disease conditions.