Mechanotransduction in bone - role of the lacuno-canalicular network

The capacity of bone tissue to alter its mass and structure in response to mechanical demands has long been recognized but the cellular mechanisms inv olved remained poorly understood. Over the last several years significant p rogress has been made in this field, which we will try to summarize. These studies emphasize the role of osteocytes as the professional mechanosensory cells of bone, and the lacuno-canalicular porosity as the structure that m ediates mechanosensing. Strain-derived flow of interstitial fluid through t his porosity seems to mechanically activate the osteocytes, as well as ensu ring transport of cell signaling molecules and nutrients and waste products . This concept allows an explanation of local bone gain and loss, as well a s remodeling in response to fatigue damage, as processes supervised by mech anosensitive osteocytes.