Therapeutic effect of Aralia cordata extracts on cartilage protection in collagenase-induced inflammatory arthritis rabbit model.

OBJECTIVE

Aralia cordata has been used to alleviate symptoms of osteoarthritis (OA) in traditional medicine. However, there is no in vivo study related with the therapeutic effects and mechanisms of Aralia cordata. On the basis of this background, our study was designed to examine the cartilage protective and proliferative effects of Aralia cordata by using a collagenase-induced osteoarthritis (CIA) rabbit model.

METHODS

The right knees of rabbits were injected intra-articularly with collagenase, and rabbits were orally administered with distilled water (vehicle), Aralia cordata (200mg/kg) and celecoxib (100mg/kg) once a day for 28 days after the initiation of the CIA.

RESULTS

In histopathologic studying by using H&E and Safranin O staining, Aralia cordata showed a cartilage protective effect in CIA rabbit femoral condyle. However, celecoxib had no effect on cartilage protection in CIA. The inflammatory mediators involved in cartilage destruction, such as COX-2 and PGE(2), were inhibited in the Aralia cordata-treated group. Aralia cordata also showed an anti-apoptotic effect through suppression of caspase-3 activity and chondrocyte proliferation induction in both in vivo and in vitro.

CONCLUSIONS

These results indicate that Aralia cordata showed cartilage protective effects through the down-regulations of COX-2 expression, PGE(2) production, caspase-3 activity, and chondrocyte proliferation in the CIA rabbit model.