Comparative analysis of diffusive and stress induced nutrient transport efficiency in the lacunar–canalicular system of osteons

Issue title: Selected papers of the Euromech Colloquium No. 420, Mechanobiology of Cells and Tissues

Article type: Research Article

Authors: Petrov, Nikola | Pollack, Solomon R.

Affiliations: Institute of Mechanics and Biomechanics, 1113 Sofia, Bulgaria Tel.: +359 88 666 872; Fax: +3592 707 498; E‐mail: nikolapetrov@dir.bg | Department of Bioengineering, University of Pennsylvania, PA19104‐6392, USA Tel.: +1 215 898 8501; Fax: +1 215 573 2071; E‐mail: spollack@seas.upenn.edu

Abstract: Marker migration experiments suggest that cyclic mechanical loading of cortical bone in vivo increases marker penetration into bone. Is this a result of stress induced fluid flow or of stress stimulation of active transport processes? Active lacunar–canalicular transport of nutrients was suggested by Ham in 1979 on the basis of the presence of actin filaments in osteocyte processes and their suspected role in cell motility. In addition, Tanaka in 1984 observed active transport of microperoxidase in bone and Tanaka‐Kamioka et al. in 1998 observed experimentally that osteocyte processes are able to actively change their form. In this study we performed parametric and comparative analyses of the transport efficiencies of diffusion and stress generated fluid flow of (glucose) nutrients in lacunar–canalicular systems in cortical bone. The result obtained is that neither diffusion nor stress induced fluid flow is capable of sustaining osteocyte viability. It is possible that cyclic stress stimulates an active nutrient transport mechanism to supplement stress flows.

Journal: Biorheology, vol. 40, no. 1-3, pp. 347-353, 2003