Orthodontic Section, Department of Growth and Development, University of Nebraska Medical Center College of Dentistry, Lincoln, NE 68583, USA.
Angle Orthod. 2011 Jul;81(4):592-9. doi: 10.2319/090310-519.1. Epub 2011 Feb 7.
To determine whether β-catenin signaling is responsive to mechanical loading in periodontal ligament (PDL) cells.
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.
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.
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.
确定β-连环蛋白信号是否对牙周韧带（PDL）细胞中的机械加载有反应。
为了确定 Wnt/β-连环蛋白信号通路的组成部分是否存在且具有功能，用氯化锂或 Wnt3a 条件培养基处理 PDL 细胞。为了确定机械应变是否激活β-连环蛋白信号，将 PDL 细胞进行压缩加载。通过免疫荧光、Western 免疫印迹和 TOPflash 测定来确定β-连环蛋白信号通路的激活情况。
模拟 Wnt 信号刺激 PDL 细胞中β-连环蛋白的核转位和 T 细胞因子/淋巴增强因子结合因子依赖性转录激活。机械加载刺激细胞质中去磷酸化的β-连环蛋白的瞬时积累，并使其向核内转位。这种应变的作用通过蛋白激酶 B 的激活和糖原合成激酶-3β的磷酸化来实现。这些与应变相关的变化不涉及低密度脂蛋白受体相关蛋白 5/Wnt 受体。
Wnt/β-连环蛋白信号通路的组成部分在 PDL 细胞中是有功能的，并可被机械加载激活。β-连环蛋白是 PDL 细胞中机械信号的效应物。
