title: [Investigation of Wnt/β-catenin signaling pathway on regulation of Runx2 in cementoblasts under mechanical stress in vitro].
abstract: OBJECTIVE
  Periodontal tissue remodeling includes remodeling of alveolar bone, periodontal ligament, and cementum. Cementoblast plays a main role in repairing root resorption. Canonical Wnt/β-catenin signaling can promote the odontogenic differentiation in osteoblast. However, the mechanism on how the orthodontic force influences the function of cementoblast and the relationship between the canonical Wnt/β-catenin signaling and Runx2 of cementoblast are not yet known. The aim of this study is focus on this relationship.
  
  
  METHODS
  OCCM30 cementoblasts were subjected to mechanical strain by four-point bending system with tension stress for 0, 3, 6, and 12 h. They were pretreated with different concentrations of Dikkopf-1 (DKK1) for 48 h. Western blot analysis was performed to detect the β-catenin levels in the nucleus. Runx2 mRNA was observed by real-time quantitative polymerase chain reaction (RT-PCR). OCCM30 cementoblasts were then pretreated with 150 ng · mL(-1) DKK1 for 48 h and subjected to mechanical strain by FX4000T system with tension stress for 12 h. Western blot analysis was conducted to detect the β-catenin levels in the nucleus, and Runx2 mRNA was observed by RT-PCR.
  
  
  RESULTS
  OCCM30 cementoblasts had significantly higher Runx2 mRNA and β-catenin levels after being loaded with mechanical stress. The amount of Runx2 mRNA in OCCM30 cementoblasts was significantly decreased by DKK1. When OCCM30 cemento-blasts were pretreated with DKK1 without stress, their β-catenin level was significantly decreased by DKK1 and Wnt signaling was blocked. When they were not pretreated with stress, the β-catenin level with DKK1 was lower than that without DKK1. Without DKK1, the β-catenin level in OCCM30 cemento- blasts increased afterbeing loaded with mechanical stress. With DKK1, the β-catenin level in OCCM30 cementoblasts, which were loaded with mechanical stress, was higher than that without mechanical stress.
  
  
  CONCLUSIONS
  Cementoblasts had higher Runx2 mRNA expression under mechanical stress because of the Wnt/β-catenin signaling pathway effect.
authors: Li
authors: L
authors: Shuqin
authors: Yang
authors: Y
authors: Shan
authors: Ren
authors: R
authors: Aishu
authors: Dai
authors: D
authors: Hongwei
mesh_terms: D002454:Cell Differentiation; D003739:Dental Cementum; D006801:Humans; D066298:In Vitro Techniques; D010006:Osteoblasts; D015398:Signal Transduction; D013314:Stress, Mechanical; D051153:Wnt Proteins; D051176:beta Catenin
chemical_list: D051153:Wnt Proteins; D051176:beta Catenin