Bone is a dynamic tissue undergoing permanent modeling and remodeling through the balanced activity of osteoclasts that resorb it and osteoblasts that produce new bone. Mechanical stimulation is known to play a key role for the maintenance of the skeleton. This implies sensing of extracellular signals by bone cells and their transduction into intracellular responses. In this review, we focus on the effects of mechanical signals on the biology of osteoclasts. We explore how mechanical stimuli directly influence osteoclast differentiation and bone resorbing activity. Podosomes, basic units of osteoclast adhesion structures, were recently shown to function as mechanosensors. We discuss how Src kinase and Rho family GTPases, which are podosomes constituents, could transduce mechanical signals towards the underlying actomyosin network in the osteoclast.
KeywordsBone Resorption Mechanical Stimulation Osteoclast Differentiation Tartrate Resistant Acid Phosphatase Osteoclast Precursor
This work was supported by research grants from the Fondation pour la Recherche Médicale (DVO20081013473) and the Association pour la Recherche sur le Cancer (3897). Virginie Vives is a recipient of a post doctoral fellowship from the Association pour la Recherche sur le Cancer. The authors are grateful to Cécile Gauthier-Rouvière, Gilles Gadea, Gilles Uzé and Philippe Fort for critical reading of the manuscript.
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