| Objective By measuring the levels of TNF-α and IL-1β in serum and synovial fluid in rabbit model of knee osteoarthritis (OA), to observe the histological changes of the cartilage and to explore the efficacy and mechanism of parthenolide on osteoarthritis with different administration routes. Methods Forty healthy purebred New Zealand rabbits were randomly divided into control group (group A, n=8), and OA model groups established using plaster cast immobilization of the right hind limb extension (n=32). After modeling the rabbits were randomly divided into 4 groups, the model of oral control group (group B), model of intra-articular injection control group (group C), parthenolide oral group (group D), parthenolide articular injection group (group E), with 8 rabbits in each group. After 6-week treatment, the expression levels of TNF-α and IL-1β in the serum and knee fluid were measured. All animals were sacrificed at 8 weeks, the histopathological changes in articular cartilage were observed using hematoxylin-eosin (HE) staining. Results TNF-α and IL-1β concentrations in synovial fluid and serum were significantly lower in rabbits of group D and E than those in group B and C (P<0.05), and the decrease was more significant in group E than in group D (P<0.05). Comparing with those in group A, the relevant sections in group B and C showed pathological cartilage damage, and the pathological scores increased (P <0.05). Comparing with those in group D and E, the pathological changes in group B and C showed some repair in articular cartilage, and the pathological scores decreased (P <0.05). Conclusion Parthenolide relieves arthritis in the animal model. The anti-inflammatory effect of intra-articular administration is better than oral administration. It inhibits secretion of serum and articular TNF-α and IL-1β, which may be one of the mechanisms of parthenolide in the treatment of arthritis. |