title: Role of the Wnt/β-catenin signaling pathway in the response of chondrocytes to mechanical loading.
abstract: In order to better understand the mechanisms by which chondrocytes respond to mechanical stimulation, ATDC5 mouse embryonic carcinoma cells were induced to differentiate into chondrocytes and then exposed to mechanical loading. To specifically elucidate the role of this pathway, the localization and expression of proteins involved in the Wnt/β-catenin signaling pathway were observed. Chondrogenic-differentiated ATDC5 cells were exposed to a 12% cycle tension load for 1, 2, 4, or 8 h. At each time point, immunofluorescence staining, western blot analysis, and qPCR were used to track the localization of β-catenin and glycogen synthase kinase-3β (GSK-3β) expression. In addition, the mRNA expression of Wnt3a, disheveled homolog 1 (Dvl-1), GSK-3β, and collagen type II were also detected. Activation of the Wnt/β-catenin signaling pathway was investigated in cells treated with Dickkopf-related protein 1 (DKK-1). β-catenin and GSK-3β protein expression increased initially and then decreased over the mechanical loading period, and the corresponding mRNA levels followed a similar trend. After application of the inhibitor DKK-1, Wnt/β‑catenin signaling was suppressed, and the mRNA expression of collagen II was also reduced. Thus, stimulation of chondrocytes with mechanical strain loading is associated with the translocation of active β-catenin from the cytoplasm to the nucleus.
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China.
authors.forename: Qiannan
authors.initials: Q
authors.lastname: Niu
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China.
authors.forename: Feifei
authors.initials: F
authors.lastname: Li
authors.affiliation: Department of Stomatology, Hospital 323 of The People's Liberation Army, Xi'an, Shaanxi 710045, P.R. China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China.
authors.forename: Xinyuan
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Stomatology, The First People's Hospital of Shuangliu County, Chengdu, Sichuan 610200, P.R. China.
authors.forename: Yucong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P.R. China.
authors.forename: Xue
authors.initials: X
authors.lastname: Feng
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D045744:Cell Line, Tumor; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism*; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism*; D051379:Mice; D013314:Stress, Mechanical; D051153:Wnt Proteins / Q000378:metabolism*; D060449:Wnt Signaling Pathway / Q000502:physiology*; D051176:beta Catenin / Q000378:metabolism*
chemical_list: D051153:Wnt Proteins; D051176:beta Catenin; D038362:Glycogen Synthase Kinase 3