Mangosteen ethanol extract alleviated the severity of collagen-induced arthritis in rats and produced synergistic effects with methotrexate

Context:Garcinia mangostana Linn. (Guttiferae) pericarp is used as a traditional medicine in South Asia to treat inflammatory diseases. Objective: This study investigates therapeutic effects of G. mangostana pericarp ethanol extract (MAN) on collagen-induced arthritis (CIA) and interactions with methotrexate in vivo. Materials and methods: Male Sprague-Dawley rats with CIA were treated with MAN (0.5 g/kg/day), methotrexate (0.5 mg/kg, bw) or combination of both for 36 days, respectively (n = 8/group). Another eight healthy and CIA rats served as normal and model control, respectively. Therapeutic effects were evaluated based on paw edema and arthritis score during the experiment and serological markers at the end of the study period. Histological and radiological examinations were used to assess joint destructions. The immune status was investigated by immunohistochemistry and flow cytometry. Results: All treatments decreased the arthritis score and paw inflammation in CIA rats. Combination regimen significantly reduced anti-cyclic citrullinated peptide antibody in CIA rats to 85.83% (p