Overexpression of DMP1 accelerates mineralization and alters cortical bone biomechanical properties in vivo.

Ankush Bhatia, Michael Albazzaz, Alejandro A Espinoza Orías, Nozomu Inoue, Lisa M Miller, Alvin Acerbo, Anne George, Dale R Sumner

Department of Anatomy and Cell Biology, Rush Medical College, 600 S Paulina St., Rm 507, Chicago, IL 60612, USA. ankush_bhatia@rush.edu

Journal of the mechanical behavior of biomedical materials 2012 Jan

filter terms:

Dentin matrix protein-1 (DMP1) is a key regulator of biomineralization. Here, we examine changes in structural, geometric, and material properties of cortical bone in a transgenic mouse model overexpressing DMP1. Micro-computed tomography and three-point bending were performed on 90 femora of wild type and transgenic mice at 1, 2, 4, and 6 months. Fourier transform infrared imaging was performed at 2 months. We found that the transgenic femurs were longer (p<0.01), more robust in cross-section (p<0.05), stronger (p<0.05), but had less post-yield strain and displacement (p<0.01), and higher tissue mineral density (p<0.01) than the wild type femurs at 1 and 2 months. At 2 months, the transgenic femurs also had a higher mineral-to-matrix ratio (p<0.05) and lower carbonate substitution (p<0.05) compared to wild type femurs. These findings indicate that increased mineralization caused by overexpressing DMP1 led to increased structural cortical bone properties associated with decreased ductility during the early post-natal period. Copyright © 2011 Elsevier Ltd. All rights reserved.

Citation

Ankush Bhatia, Michael Albazzaz, Alejandro A Espinoza Orías, Nozomu Inoue, Lisa M Miller, Alvin Acerbo, Anne George, Dale R Sumner. Overexpression of DMP1 accelerates mineralization and alters cortical bone biomechanical properties in vivo. Journal of the mechanical behavior of biomedical materials. 2012 Jan;5(1):1-8