title: Intra-articular delivery of anti-Hif-2α siRNA by chondrocyte-homing nanoparticles to prevent cartilage degeneration in arthritic mice.
abstract: Hypoxia-inducible factor-2α (Hif-2α) is a potential therapeutic target for osteoarthritis (OA), but the application of this target in the delivery of therapeutic agents to chondrocytes remains a challenge. A chondrocyte-targeting vector was constructed in a previous study to enhance transfection efficiency and specificity of chondrocytes in vivo. This study used vectors to deliver small-interfering RNA (siRNA) and silenced Hif-2α expression to prevent cartilage degeneration in OA-affected mice. After siRNA transfection was conducted by cartilage-targeting nanoparticles, the protein levels of Hif-2α, matrix metalloproteinases (MMP-13, -9), a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS-4, -5), vascular endothelial growth factor (VEGF), type X collagen and nuclear factor (NF)-κB in interleukin-1-beta (IL-1β)-stimulated chondrocytes were determined. Chondrocyte-targeting ability was also determined by fluorescein isothiocyanate (FITC)-labeled siRNA tracking under a confocal microscope. OA model was established by surgically destabilizing the knee joints of a mouse. Hif-2α siRNA was then delivered intra-articularly with nanoparticles in vivo. Cartilage degeneration and synovium inflammation in the knee joints were analyzed by histomorphometry. IL-1β levels in the synovial fluid were also measured by enzyme-linked immunosorbent assay. In vitro assay results showed that catabolic factors, including Hif-2α, MMP-13 and -9, ADAMTS-4, VEGF, collagen type X and NF-κB, were downregulated after Hif-2α-siRNA transfection by chondrocyte-targeting nanoparticles. In vivo assay results with FITC-labeled siRNA tracking also confirmed that nanoparticles promoted the local concentration and prolonged the retention time of siRNA in the cartilage. Histological analysis results confirmed that nanoparticle-mediated siRNA maintained cartilage integrity and alleviated synovium inflammation. IL-1β levels decreased after siRNA was silenced by nanoparticles. Thus, chondrocyte-targeting nanoparticles could deliver Hif-2α siRNA to cartilage and specifically inhibit the expression of catabolic proteins.
authors: Department of Sports Medicine, Beijing Key Laboratory of Sports Injury, Institute of Sports Medicine, Peking University Third Hospital, Beijing, PR China.
authors: Y
authors: Y
authors: Pi
authors: Department of Sports Medicine, Beijing Key Laboratory of Sports Injury, Institute of Sports Medicine, Peking University Third Hospital, Beijing, PR China.
authors: X
authors: X
authors: Zhang
authors: Department of Sports Medicine, Beijing Key Laboratory of Sports Injury, Institute of Sports Medicine, Peking University Third Hospital, Beijing, PR China.
authors: Z
authors: Z
authors: Shao
authors: Department of Sports Medicine, Beijing Key Laboratory of Sports Injury, Institute of Sports Medicine, Peking University Third Hospital, Beijing, PR China.
authors: F
authors: F
authors: Zhao
authors: Department of Sports Medicine, Beijing Key Laboratory of Sports Injury, Institute of Sports Medicine, Peking University Third Hospital, Beijing, PR China.
authors: X
authors: X
authors: Hu
authors: Department of Sports Medicine, Beijing Key Laboratory of Sports Injury, Institute of Sports Medicine, Peking University Third Hospital, Beijing, PR China.
authors: Y
authors: Y
authors: Ao
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002358:Cartilage, Articular / Q000378:metabolism / Q000473:pathology*; D019902:Chondrocytes; D004195:Disease Models, Animal; D005822:Genetic Vectors; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D007249:Inflammation; D007719:Knee Joint / Q000378:metabolism / Q000473:pathology; D051379:Mice; D053758:Nanoparticles / Q000378:metabolism / Q000627:therapeutic use*; D010003:Osteoarthritis / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control* / Q000628:therapy; D010455:Peptides / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use; D012333:RNA, Messenger / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D013583:Synovial Membrane / Q000473:pathology; D000099162:Endothelial PAS Domain-Containing Protein 1
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D010455:Peptides; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D000099162:Endothelial PAS Domain-Containing Protein 1; C497443:Hif1a protein, mouse