Anti-arthritic activity of a lipophilic woad (Isatis tinctoria) extract.

A dichloromethane extract of Isatis tinctoria was tested in the adjuvant-induced arthritis model in rats. The extract (150 mg/kg p. o.) leads to a significant reduction of paw oedema. Radiographic, histological and clinical assessment confirmed reduced damage of cartilage and signs of inflammatory response in comparison to untreated control. No significant differences were observed in the tissular levels of cyclooxygenases 1 and -2, and of inducible nitric oxide synthase in Isatis treated and untreated animals. High dose treatment with Isatis extract for two weeks did not result in macroscopic lesions of the gastric mucosa.