Suppression of early experimental osteoarthritis by in vivo delivery of the adenoviral vector-medated NF-κBp65-specific siRNA

Objective: This study was to use adenoviral vector-mediated nuclear factor-kappa Bp65 (NF-kappa Bp65)-specific siRNA (Ad-siRNA(NF-kappa BP65)) to suppress the progression of early osteoarthritis (OA) in rat model, and therefore to explore a new gene therapy for OA. Methods: Reverse transcription polymerase chain reaction was performed to confirm the silencing effect of Ad-siRNA(NF-kappa Bp65) in cultured rat chondrocytes. Transection of the medial collateral ligament plus partial medial meniscectomy was operated in the knee of rats to establish OA model. Histological analysis was made to assess the morphological change of cartilage and synovium, and enzyme-linked immunosorbent assay was made to measure the expression of cytokines, such as interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha), in synovial fluid. The silencing effect of Ad-siRNA(NF-kappa Bp65) on NF-kappa Bp65 in cartilage and synovium of knee was measured with Western blot and the activation of NF-kappa B was measured with electrophoretic mobility shift assays. Results: Ad-siRNA(NF-kappa Bp65) can inhibit the activation of NF-kappa B and the expression of NF-kappa Bp65 in cartilage and synovium of the knee, restrain the induction of IL-1 beta and TNF-alpha in synovial fluid, alleviate the inflammation of synovium and reduce the degradation of cartilage in early phase of experimental OA. Conclusions: Ad-siRNA(NF-kappa Bp61) can suppress the progression of the early experimental OA which suggests that Ad-siRNA(NF-kappa Bp65) has potential to be a useful preventive and therapeutic agent for CA. (c) 2007 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.