Osteocytes and osteoclasts, a relationship under strain

Osteoclasts strongly contribute to proper bone quality and function. Their actions are largely coordinated by osteocytes, i.e., osteocytes devoid of mechanical stimuli produce a multitude of membrane bound and soluble factors that stimulate the formation of osteoclasts. Among these are inflammatory factors, the most well known being receptor activator of nuclear factor κB ligand, matricellular proteins, and growth factors/morphogens such as WNTs. The intimate relationship between osteocytes and osteoclasts suggests that a better knowledge of the factors produced by osteocytes could lead to a better understanding of osteoclast formation and activity. © 2014 Springer Science+Business Media New York.