The Role of Exosomes in Bone Remodeling: Implications for Bone Physiology and Disease

Figure 1

The role of exosomes in the intricate processes of physiological bone remodeling. In bone remodeling, exosomes are exchanged mainly among osteoblasts, osteocytes, and osteoclasts and their precursors and also secreted by adipocytes, myoblasts, and the endothelium (shown), as well as by dendritic cells and synovial fibroblasts (not shown). Some exosomes function as mineral nucleation sites (“mineralizing exosomes” or “matrix vesicles”). Exosomes carry a variety of biomolecules such as proteins and miRNAs (upper right corner), which favor either bone synthesis (green arrows) or bone resorption (red arrows) depending on the type of secreting and receiving cell.