Bone Development Research Paper

Skeletal Development. Bone is a living tissue and from birth until death, it is constantly undergoing remodeling processes to maintain integrity and mineral composition. Remodeling is a process that is tightly regulated through the coordination of osteoclasts, which regulate bone resorption and osteoblasts, which mediate bone formation.

Osteoclasts are the cells responsible for bone resorption. The formation and activation of osteoclasts is mediated by the ratio of RANKL to osteoprotegerin (OPG), interleukin-1 (IL-1), interleukin-6 (IL-6), colony-stimulating factor (CSF), parathyroid hormone (PTH), 1,25-dihydroxyvitamin-D, and calcitonin (15, 18). Activated osteoclasts use integrin receptors beta-1 and αvβ3 found on their membrane to attach to bone by connecting to bone matrix peptides by binding to collagen, fibronectin, and laminin while αvβ3 binds to osteopontin and sialoprotein (19). Once bound to bone, osteoclasts form two polarized structures, which give them the ability to degrade bone tissue. This occurs through the

During this phase, preosteoblasts are recruited and transform into osteoblasts and will migrate to the bone surface to begin bone formation. Once production begins, transforming growth factor-beta (TGF-β) is released from the matrix and will decrease production of RANKL by osteoblasts, thereby inhibiting osteoclast activity (22). In order for bone formation to occur, osteoblasts must create new collagenous and non-collagenous substance, for the matrix while also monitoring mineralization of the matrix by ensuring proper calcium and phosphate deposits (22). They also produce high amounts of type 1 collagen, whose purpose is to fill the hollow parts of the bone made during the resorption phase. Throughout this process, various osteoblasts become embedded within the bone matrix, and become osteoclasts (23).

Factors Related to Bone