title: Mechanical loading activates β-catenin signaling in periodontal ligament cells.
abstract: OBJECTIVE
  To determine whether β-catenin signaling is responsive to mechanical loading in periodontal ligament (PDL) cells.
  
  
  METHODS
  To determine whether Wnt/β-catenin signaling pathway components are present and functional, PDL cells were treated with lithium chloride or Wnt3a-conditioned media. To determine whether mechanical strain activates β-catenin signaling, PDL cells were subjected to compressive loading. Activation of the β-catenin signaling pathway was determined by immunofluorescence, Western immunoblotting, and TOPflash assay.
  
  
  RESULTS
  Mimicking Wnt signaling stimulates β-catenin nuclear translocation and T-cell factor/lymphoid enhancer binding factor-dependent transcriptional activation in PDL cells. Mechanical loading stimulates a transient accumulation of dephosphorylated β-catenin in the cytoplasm and its translocation to the nucleus. This effect of strain acts through activation of protein kinase B and phosphorylation of glycogen synthase kinase-3 beta. These strain-related changes do not involve the low-density lipoprotein receptor-related protein 5/Wnt receptor.
  
  
  CONCLUSIONS
  The Wnt/β-catenin signaling pathway components are functional and activated by mechanical loading in PDL cells. β-catenin serves as an effector of mechanical signals in PDL cells.
authors.affiliation: Orthodontic Section, Department of Growth and Development, University of Nebraska Medical Center College of Dentistry, Lincoln, NE 68583, USA. spremaraj@unmc.edu
authors.forename: Sundaralingam
authors.initials: S
authors.lastname: Premaraj
authors.forename: Isabela
authors.initials: I
authors.lastname: Souza
authors.forename: Thyagaseely
authors.initials: T
authors.lastname: Premaraj
mesh_terms: D021581:Active Transport, Cell Nucleus; D002478:Cells, Cultured; D019245:Compressive Strength; D017077:Culture Media, Conditioned; D003799:Dental Stress Analysis; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D006801:Humans; D026502:LDL-Receptor Related Proteins / Q000378:metabolism; D060492:Low Density Lipoprotein Receptor-Related Protein-5; D010513:Periodontal Ligament / Q000166:cytology / Q000378:metabolism*; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D033081:Shear Strength; D015398:Signal Transduction; D013314:Stress, Mechanical; D051820:TCF Transcription Factors / Q000378:metabolism; D014087:Tooth Movement Techniques; D015533:Transcriptional Activation; D051153:Wnt Proteins / Q000378:metabolism; D060508:Wnt3 Protein; D060509:Wnt3A Protein; D051176:beta Catenin / Q000378:metabolism*
chemical_list: D017077:Culture Media, Conditioned; D026502:LDL-Receptor Related Proteins; C555482:LRP5 protein, human; D060492:Low Density Lipoprotein Receptor-Related Protein-5; D051820:TCF Transcription Factors; C555510:WNT3A protein, human; D051153:Wnt Proteins; D060508:Wnt3 Protein; D060509:Wnt3A Protein; D051176:beta Catenin; D051057:Proto-Oncogene Proteins c-akt; D038362:Glycogen Synthase Kinase 3