PRP-Derived Exosomes Promote Cartilage Repair by Suppressing Oxidative Stress and Inflammatory Signaling in Chondrocytes: An In Vitro and Ex Vivo Study

Abstract Osteoarthritis (OA) is a degenerative musculoskeletal condition characterized by progressive cartilage degradation accompanied by joint inflammation, for which current treatments offer only symptomatic relief without halting progression. This study compared the regenerative and anti-inflammatory properties of platelet-rich plasma (PRP) and its exosome-enriched derivative (PRP-Exos) on human chondrocytes and cartilage explants under IL-1β stimulated inflammatory conditions. PRP-derived exosomes (PRP-Exos) were extracted using an aqueous two-phase separation method and subsequently evaluated for their morphological characteristics and particle size distribution by transmission electron microscopy and nanoparticle tracking analysis. The findings revealed that treatment with PRP-Exos produced greater improvements in chondrocyte proliferation, migratory capacity, and extracellular matrix synthesis compared with PRP. Furthermore, PRP-Exos more effectively suppressed regulation of inflammatory cytokines and cartilage-degrading enzymes, including MMP-3 and MMP-13, through modulation of the Wnt5a, NF-κB, and MAPK signaling pathways. Ex vivo analysis confirmed that PRP-Exos treatment led to superior cartilage structural maintenance and increased proteoglycan content in chondral defects. These findings conclude that PRP derived exosomes possess superior regenerative properties and improved tissue penetration over conventional PRP, positioning them as promising cell free, next generation therapeutics for OA.