Osteocyte-derived exosomes regulate the DLX2/wnt pathway to alleviate osteoarthritis by mediating cartilage repair.

BACKGROUND:Chondrocyte viability, apoptosis, and migration are closely related to cartilage injury in osteoarthritis (OA) joints. Exosomes are identified as potential therapeutic agents for OA. OBJECTIVE:This study aimed to investigate the role of exosomes derived from osteocytes in OA, particularly focusing on their effects on cartilage repair and molecular mechanisms. METHODS:An injury cell model was established by treating chondrocytes with IL-1β. Cartilage repair was evaluated using cell counting kit-8, flow cytometry, scratch test, and Western Blot. Molecular mechanisms were analyzed using quantitative real-time PCR, bioinformatic analysis, and Western Blot. An OA mouse model was established to explore the role of exosomal DLX2 in vivo. RESULTS:Osteocyte-released exosomes promoted cell viability and migration, and inhibited apoptosis and extracellular matrix (ECM) deposition. Moreover, exosomes upregulated DLX2 expression, and knockdown of DLX2 activated the Wnt pathway. Additionally, exosomes attenuated OA in mice by transmitting DLX2. CONCLUSION:Osteocyte-derived exosomal DLX2 alleviated IL-1β-induced cartilage repair and inactivated the Wnt pathway, thereby alleviating OA progression. The findings suggested that osteocyte-derived exosomes may hold promise as a treatment for OA.