Cyclic Stretch Enhances Osteogenic Differentiation of Human Periodontal Ligament Cells via YAP Activation

Figure 1

Cyclic stretch activates YAP in human periodontal ligament cells (HPDLCs). (a) Cyclic stretch increased the nuclear localization of YAP in HPDLCs. (b) Quantitative analysis of the cellular distribution of YAP in HPDLCs based on whether it was higher in the nucleus (N>C), higher in the cytoplasm (N<C), or evenly distributed between the nucleus and cytoplasm (N=C). The percentage of cells in each category was scored after observing cells in three different microscopic fields. (c) Nuclear expression of YAP was increased in stretched HPDLCs. (d) Relative grey values of each band (in (c)) were normalized to the level of GAPDH. , p < 0.001. (e) Increased mRNA expression of YAP downstream genes in stretch-stimulated HPDLCs. The mRNA expression of CTGF and CYR61 was analyzed by qRT-PCR. The relative expression was calculated after normalization to the GAPDH level. , p < 0.001; , p < 0.01. All data was based on three independent experiments.

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