Inflammation and extracellular matrix (ECM) degradation have been implicated in the pathological process of osteoarthritis (OA). α-Cyperone is the main active component of the traditional Chinese medicine Cyperus rotundus L. In this study, we found that α-Cyperone abolished the IL-1β-induced production of inflammatory cytokines in isolated rat chondrocytes, such as cyclooxygenase-2 (COX-2), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and inducible nitric oxide synthase (iNOS), in a dose-dependent manner (0.75, 1.5 or 3 μM). Also, the results showed that α-Cyperone downregulated the expression of metalloproteinases (MMPs) and thrombospondin motifs 5 (ADAMTS5), and upregulated the expression of type-2 collagen. Mechanistically, molecular docking tests revealed that α-Cyperone stably and effectively binds to p65, p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). α-Cyperone inhibited NF-κB activation by blocking its nuclear transfer, and decreasing the phosphorylation of mitogen-activated protein kinase (MAPKs). In addition, in vivo studies based on a mouse model of arthritis showed that α-Cyperone prevented the development of osteoarthritis. Therefore, α-Cyperone may be a potential anti-OA drug.
Keywords: extracellular matrix degradation; inflammation; osteoarthritis; α-Cyperone.