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

Figure 6

Activation of YAP in the PDLCs in the OTM murine model. Histological section at the tension side of the periodontium zone around the mesial root of right upper first molar during OTM was analyzed by immunohistochemical staining for YAP (a, brown) and RUNX2 (b, brown) in control group (Control) and experiment group after mechanical loading for 3 days (Exp 3d), 6 days (Exp 6d), and 12 days (Exp 12d). Nuclei were counterstained with hematoxylin (blue). The red boxed regions (tension side) and white boxed regions (compression side) were shown at a higher magnification. r for Root, ab for alveolar bone, and p for periodontium, while black arrow indicates the direction of force. The percentages of positive nuclear staining of YAP (c) and RUNX2 (d) at the tension side of periodontium were analyzed. , P < 0.01; , P < 0.01.

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