Lycium barbarum polysaccharide attenuates type II collagen-induced arthritis in mice.

No curative treatment is yet available for rheumatoid arthritis (RA), wherein chronic synovitis progresses to cartilage and bone destruction. Considering the recently recognized anti-inflammatory properties of Lycium barbarum polysaccharide (LBP; a derivative of the goji berry), we established the collagen type II-induced arthritis (CIA) mouse model to investigate the potential therapeutic effects and mechanisms of LBP. The CIA-induced changes and LBP-related effects were assessed by micro-computed tomography measurement of bone volume/tissue volume and by ELISA and western blotting detection of inflammatory mediators and matrix metalloproteinases (MMPs). The CIA mice showed substantial bone damage, bone loss, and increased concentrations of TNF-α, IL-6, IL-17, PGE2, MIP-1, anti-type II collagen IgG, MMP-1, and MMP-3. LBP treatments produced significant dose-dependent improvements in CIA-induced bone damage and bone loss, and significantly reduced CIA-stimulated expression of the inflammatory mediators and MMPs. Thus, LBP therapy can preserve bone integrity in CIA mice, possibly through down-regulation of inflammatory mediators.