Osteoarthritis (OA) is mainly characterized by articular cartilage degeneration, synovial fibrosis, and inflammation. LncRNA CRNED (colorectal neoplasia differentially expressed) has been reported to be down-regulated in age-related OA, but its role in injury-induced OA needs to be further explored. In this study, an OA rat model was established by using anterior cruciate ligament transection, and the adenovirus-mediated CRNED overexpression (Ad-CRNED) or DACT1 (dapper antagonist of catenin-1)

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... nterference (sh-DACT1) vectors were injected into the rat model via tail vein. Besides, chondrocyte‑like ATDC5 cells were treated with IL-1β (10 ng/mL) to simulate OA conditions in vitro. We found that overexpression of CRNED alleviated cartilage damage and synovitis in OA rats, and suppressed IL-1β-induced apoptosis, inflammation, and extracellular matrix (ECM) degradation in chondrocyte‑like ATDC5 cells, while silencing DACT1 effectively antagonized the protective effect of CRNED both in vivo and in vitro. Mechanism studies revealed that DACT1 could act as a downstream target of CRNED. By recruiting p300, CRNED promoted the enrichment of H3K27ac in the DACT1 promoter, thus promoting DACT1 transcription. In addition, CRNED hindered the activation of the Wnt/β-catenin pathway in IL-1β-stimulated cells by inducing DACT1 expression. In conclusion, CRNED promoted DACT1 expression through epigenetic modification and restrained the activation of Wnt/β-catenin signaling to impede the progression of OA.