Peimine suppresses interleukin­1ß­induced inflammation via MAPK downregulation in chondrocytes.

ABSTRACT

Osteoarthritis (OA) is the most common type of degenerative joint disease and secreted inflammatory molecules serve a pivotal role in it. Peimine has been reported to have anti­inflammatory activity. In order to investigate the potential therapeutic role of Peimine in OA, mouse articular chondrocytes were treated with IL­1ß and different doses of Peimine in vitro. The data revealed that Peimine not only suppressed IL­1ß­induced production of nitric oxide (NO) and prostaglandin E2, but also reduced the protein levels of inducible NO synthase (iNOS) and cyclooxygenase­2 (COX­2). In addition, Peimine inhibited the IL­1ß­induced mRNA expression of matrix metalloproteinase (MMP)­1, MMP­3, MMP­9, MMP­13, a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)­4 and ADAMTS­5. Furthermore, Peimine inhibited IL­1ß­induced activation of the mitogen­activated protein kinase (MAPK) pathway. The protective effect of Peimine on IL­1ß­treated chondrocytes was attenuated following activation of the MAPK pathway, as demonstrated by the increased expression levels of MMP­3, MMP­13, ADAMTS­5, iNOS and COX­2 compared with the Peimine group. The in vivo data suggested that Peimine limited the development of OA in the mouse model. In general, the data indicate that Peimine suppresses IL­1ß­induced inflammation in mouse chondrocytes by inhibiting the MAPK pathway, suggesting a promising therapeutic role for Peimine in the treatment of OA.