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Title: Chemically modified curcumin (CMC2.24) alleviates osteoarthritis progression by restoring cartilage homeostasis and inhibiting chondrocyte apoptosis via the NF-κB/HIF-2α axis
Disorders of cartilage homeostasis and chondrocyte apoptosis are major events in the pathogenesis of osteoarthritis (OA). Herein, we sought to assess the chondroprotective effect and underlying mechanisms of a novel chemically modified curcumin, CMC2.24, in modulating extracellular matrix (ECM) homeostasis and inhibiting chondrocyte apoptosis. Rats underwent the anterior cruciate ligament transection and medial menisci resection were treated by intra-articular injection with CMC2.24. In vitro study, rat chondrocytes were pretreated with CMC2.24 before stimulation with sodium nitroprusside (SNP). The effects of CMC2.24 on cartilage homeostasis and chondrocyte apoptosis were observed. The results from in vivo studies demonstrated that the intra-articular administration of CMC2.24 delayed cartilage degeneration and suppressed chondrocyte apoptosis. CMC2.24 ameliorated osteoarthritic cartilage destruction by promoting collagen 2a1 production and inhibited cartilage degradation and apoptosis by suppressing hypoxia-inducible factor-2a (Hif-2α), matrix metalloproteinase-3 (MMP-3), runt-related transcription factor 2 (RUNX2), cleaved caspase-3, vascular endothelial growth factor (VEGF), and the phosphorylation of IκBα and NF-κB p65. The in vitro results revealed that CMC2.24 exhibited a strong inhibitory effect on SNP-induced chondrocyte catabolism and apoptosis. The SNP-enhanced expression of Hif-2α, catabolic and apoptotic factor, decreased after CMC2.24 treatment in a dose-dependent manner. CMC2.24 pretreatment effectively inhibited SNP-induced IκBα and NF-κB p65 phosphorylation in rat more » chondrocytes, whereas the pretreatment with NF-κB antagonist BMS-345541 significantly enhanced the effects of CMC2.24. Taken together, these results demonstrated that CMC2.24 attenuates OA progression by modulating ECM homeostasis and chondrocyte apoptosis via suppression of the NF-κB/Hif-2α axis, thus providing a new perspective for the therapeutic strategy of OA. « less
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Journal of Molecular Medicine
Sponsoring Org:
National Science Foundation
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