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

Figure 4

Forced overexpression of YAP promotes the osteogenic differentiation of HPDLCs. (a) YAP was overexpressed in HPDLCs using pCDH-YAP, and the mRNA expression level of YAP was detected by qRT-PCR. , p < 0.001. (b) The protein expression of YAP was analyzed using immunoblots. (c) Quantitative analysis of the blots (in (b)), the data was normalized to GAPDH. , p < 0.001. (d) Alkaline phosphatase activity of HPDLCs was enhanced by the overexpression of YAP. The positive cells for the ALP were stained with NBT-formazan (dark blue). (e) The ALP activities were quantified using an ALP reagent kit. The activities were normalized to the protein concentration. , P < 0.01. (f) Osteogenesis related genes were increased in the YAP overexpressed HPDLCs. The relative expression levels of osteopontin (OPN), RUNX2, collagen type 1 (COL1), alkaline phosphatase (ALP), osterix (OSX), and osteocalcin (OCN) were normalized to GAPDH. , p < 0.05; , p < 0.01; , p < 0.001. All data was based on three independent experiments.

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