Standardized ethyl acetate fraction from the roots of Brassica rapa attenuates the experimental arthritis by down regulating inflammatory responses and inhibiting NF-κB activation

This study was undertaken to investigate the anti-arthritic potential of a standardized ethyl acetate fraction from the roots of Brassica rapa (EABR) and to explore the molecular mechanisms in adjuvant-induced arthritic rats and macrophages. In AIA-induced arthritic rats, EABR significantly reduced paw swelling, an arthritic index, serum rheumatoid factor, and tissue expression ratio of RANKL/OPG versus vehicle-administered group. This was found to be well correlated with significant suppressions in productions of PGE2, NO, and pro-inflammatory cytokines and in activations of NF-kappa B in AIA-induced paw tissues and LPS-induced macrophages. EABR attenuated NF-kappa B activation by reducing the nuclear translocation and phosphorylation of the p65 NF-kappa B, which were accompanied by parallel reductions in the degradation and phosphorylation of I kappa B alpha after blocking the phosphorylation mediated IKK activation. The findings suggest EABR exerts its anti-arthritic and anti-inflammatory properties via NF-kappa B inactivation in vitro and in vivo, and that EABR is a potential therapeutic for the treatment of arthritis and inflammation-associated disorders. (C) 2014 Elsevier Ltd. All rights reserved.