Chrysin, a 5,7-dihydroxyflavone restrains inflammatory arthritis in rats via subsiding oxidative stress biomarkers and inflammatory cytokines

This study was intended to appraise the anti-inflammatory and anti-arthritic potential of Chrysin (CR), a natural dietary flavone found in several plant genera, including Passiflora and Propalis, and honey. The in vitro anti-arthritic potential was assessed by protein denaturation and membrane stabilization assays. The acute anti-inflammatory action was assessed by Carrageenan and Xylene induced oedema models in Wistar rats. For determining anti-arthritic potential, 0.1 ml Complete Freund’s adjuvant was injected into the left hind paw of rats to induce adjuvant-induced arthritis, followed by initiation of treatment with individual CR at 25, 50, 100 mg/kg and in combination with methotrexate (MTX) by oral gavage for 21 days. The standard treatment group was given MTX (1 mg/kg). Treatment with MTX, chrysin and their combination exhibited a notable inhibition of paw oedema and pain, restoration of body weight and immune organ weight as evident by the histology of ankle joints. Treatment with chrysin alone and in combination significantly (p < 0.0001) restored altered blood parameters (CRP, RF, Hb, WBC, and platelets) with notable (p < 0.0001) down-regulation of interleukin (IL)-6,-1β, tumor necrosis factor-α, NF-κβ, and cyclooxygenase-2 and up-regulation (p < 0.0001) of IL-4, 10, and I-κβ in contrast to disease control rats. The treatment with the combination noticeably improved the superoxide dismutase, and catalase activities while reduced the peroxidation level in liver homogenate. It can be concluded from the findings that chrysin especially in combination with MTX ameliorated CFA-induced arthritis owing to its profound anti-oxidant, analgesic and anti-inflammatory actions.