The protective effect of chondroitin from Raja kenojei cartilage on collagen-induced Arthritis in DBA/1J mice

In this study, we evaluated whether the oral administration of chondroitin from the cartilage of Raja kenojei is effective on the progression of rheumatoid arthritis (RA), using collagen-induced arthritic (CIA) mice. Arthritis development was delayed dose-dependently in the chondroitin-treated groups. The pre- and late-treated groups receiving 1,000 mg/kg of chondroitin had clinical scores that were reduced significantly by 56.9 (p<0.05) and 43.3% (p<0.05), respectively, compared to the vehicle-treated groups. Hematoxylin eosin staining and X-ray radiography showed that the chondroitins reduced the infiltration of inflammatory cells and prevented joint destruction of the knee and paw. Reverse transcription-polyerase chain reaction analysis revealed that chondroitin administration inhibited the expressions of tumor necrosis factor-α (TNF-α), interlukin-1β (IL-1β), and interferon-γ (IFN-γ) in joints more than the administration of vehicle. Chondroitin treatment also decreased the production of rheumatoid factors (RF), IgG and IgM, in the serum of CIA mice. These results indicate that chondroitin administration has a protective effect involving the inhibition of pro-inflammatory cytokine production in CIA mice.