Abstract

Aim: To assess the effect of petroleum ether extract (PEE), ethyl acetate extract (EthE), and ethanol extract (EAE) of Trichilia monadelpha stem bark on bone histomorphology in arthritis. Methods: Percentage inhibition of edema and arthritic scores in complete Freund’s adjuvant-induced (0.1 ml of 5 mgml-1 of heat killed Mycobacterium tuberculosis in paraffin oil injected sub-plantar into the right hind paw) arthritic Sprague-Dawley rats treated with PEE, EthE, or EAE (10, 30, and 100 mgkg-1), dexamethasone (0.3-3.0 mgkg-1) or methotrexate (0.1–1.0 mgkg-1) over a 28-day period were estimated. Rat paws were radiographed and scored. Body weights were taken and paw tissues harvested for histopathological studies. Results: The extracts significantly (P≤0.01-0.0001) and dose-dependently reduced the polyarthritic phase of arthritis. EAE and PEE significantly (P≤0.01-0.0001) minimized edema spread from acute arthritic phase (day 0-10) to polyarthritic phase (day 10-28). EthE improved deteriorated body weight in arthritis. All extracts significantly (P≤0.05-0.01) improved arthritic score; reducing erythema, swelling and joint rigidity, and also significantly (P≤0.05-0.01) reduced hyperplasia, pannus formation, and exudation of inflammatory cells into synovial spaces. Conclusion: The stem bark extracts of Trichilia monadelpha reduce bone tissue damage and resorption associated with adjuvant-induced arthritis, hence could be useful in managing arthritis in humans.

Key words: arthritic paw radiography, erythema, subchondral erosion, periostitis, osteolysis, Trichilia monadelpha