These authors contributed equally to this work.
Cyclic stretching force-induced early apoptosis in human periodontal ligament cells
Article first published online: 19 JAN 2008
© 2008 The Authors
Volume 14, Issue 3, pages 270–276, April 2008
How to Cite
Zhong, W., Xu, C., Zhang, F., Jiang, X., Zhang, X. and Ye, D. (2008), Cyclic stretching force-induced early apoptosis in human periodontal ligament cells. Oral Diseases, 14: 270–276. doi: 10.1111/j.1601-0825.2007.01375.x
- Issue published online: 10 FEB 2008
- Article first published online: 19 JAN 2008
- Received 15 November 2006; revised 17 December 2006, 28 December 2006; accepted 4 January 2007
- early apoptosis;
- human periodontal ligament cells;
- stretching force
Objective: Human periodontal ligament (PDL) cells occur changes in morphology and express relative protein by stretching force. However, whether stretching force, especially excessive stretching force, induces PDL cell apoptosis is not yet clearly understood. In the present study we investigated the relationship between early apoptosis and stretching force in human PDL cells in vitro.
Materials and methods: The human PDL cells were obtained from healthy premolars. After three to five passages, the cells were stretched by strain 1%, 10% and 20% for 30 min, 1 h, 6 h and 12 h, then early apoptosis were detected through annexin fluorescein isothiocyanate (V-FITC) binding by flow cytometry and confocal laser scanning microscopy.
Results: The experiments indicated that human PDL apoptotic cells in the early stage increased in a time- and force-dependent manner in response to stretching strain within 6 h, and then apoptosis decreased at 12 h. Human PDL cells which stretched inclined parallel to each other and aligned their long axis perpendicular to the stretching force vector, but in the centre of the disc, cells showed minimal deformation and unidirectional alignment of PDL cells.
Conclusion: The overall results suggested that stretching force not only influenced morphology but also induced early apoptosis in human PDL cells.