Osteocytes and their role in bone remodeling

Abstract

Osteocytes are former osteoblasts that become entombed during the process of bone deposition and are regularly distributed throughout the mineralized bone matrix. Osteocytes are the most abundant cells in bone comprising more than 90% of cells within the matrix or on the bone surfaces. Increasing evidence supports the notion that osteocytes coordinate the function of osteoblasts and osteoclasts in response to both mechanical and hormonal stimuli. Osteocytes produce and secrete factors (such as sclerostin) that affect other bone cells by paracrine/autocrine mechanisms. In addition, osteocytes produce and secrete hormones (such as FGF23) that affect other tissues by endocrine mechanisms. This review summarizes the current understanding of osteocyte functions and the role of these cells in bone remodeling.