Osteocytes as mechanosensors in bone

Abstract

Osteocytes and lacunae and canaliculi system containing them form a syncytial network known as the osteocytic lacuno-canalicular system (OLCS), through which they also communicate with osteoblastic cells on the bone surface. There is evidence that the presence and absence of mechanical loads on bone cause changes in the expression of a variety of factors in osteocytes, suggesting that osteocytes may play a role as mechanosensors in the regulation of adaptive bone modeling and remodeling processes. Acting as mechanosensors of bone, osteocytes sense mechanical stimuli, transduce them into biochemical signals, and through the release of a number of factors, they communicate the stimulus to effector cells (osteoblasts and osteoclasts). It is through their cytoplasmic processes and the communication network in the OLCS that osteocytes have this ability. The changes in the perilacunar-pericanalicular environment would seemingly serve to amplify the strain, and enable signal transmission to the cells. The aim of this review is to present current knowledge on the mechanosensory function of osteocytes, and its relation with adaptive bone modeling and remodeling processes.