Therapeutic effect of edaravone on osteoarthritis: targeting NRF2 signaling and mitochondrial function.

BACKGROUND: Osteoarthritis (OA), the most prevalent form of arthritis, is swiftly emerging as a chronic health condition, that poses the primary cause of disability and significant socioeconomic burden. Despite its prevalence, effective therapeutic options for OA remain elusive. This study seeks to explore the therapeutic potential of edaravone (EDA), a FDA-approved free radical scavenger, in the context of OA development and to elucidate its underlying mechanisms. METHODS: In vitro, oxidative stress models were induced by stimulating chondrocytes with t-butylhydroperoxide (TBHP); then, we investigated the influence of EDA on chondrocyte dysfunction, apoptosis, inflammatory responses and mitochondrial function in TBHP-treated chondrocytes, along with the underlying mechanisms. In vivo, destabilization of the medial meniscus (DMM) model was used to investigate the impact of EDA on OA progression. Nrf2 (-/-) mice were applied to determine the potential role of NRF2 as a target for EDA. RESULTS: EDA notably alleviates chondrocyte dysfunction triggered by oxidative stress, safeguards chondrocytes from apoptosis and inflammatory responses, and preserves mitochondrial function and redox balance within chondrocytes. At the molecular level, EDA appears to halt the progression of OA by engaging and activating the nuclear factor erythroid 2-related factor 2 (NRF2) pathway, which is crucial for maintaining mitochondrial function and redox equilibrium. Notably, the protective effects of EDA on OA are abolished in Nrf2 (-/-) mice, underscoring the significance of the NRF2 signaling pathway in mediating EDA's therapeutic effects. CONCLUSION: EDA has the potential to mitigate chondrocyte degeneration, thereby slowing the progression of OA. Thus, EDA may represent a novel therapeutic agent for the treatment of OA, potentially expanding its clinical utility. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: As a clinically licensed drug used for the treatment of neurological disorders, edaravone has shown promising therapeutic effects on OA development. Mechanistically, edaravone stabilized mitochondrial function and maintained redox homeostasis by activating NRF2 signaling pathway. The protective effects of edaravone against OA were verified in vivo and in vitro. These findings presented robust evidence for repurposing edaravone for the treatment of OA in clinic.