Osteocalcin as a Skeletal Maturity Indicator:A Review

Bone mineral metabolism helps in understanding the sequence of boneloss and bone remodeling and in identifying those persons at risk from osteoporosis. One of the approaches that has yielded useful information is the examination of the role of collagenous and noncollagenous bone proteins in bone mineral metabolism. Osteoblasts are the cells responsible for new bone formation, and osteoclasts the cells for resorption. Osteocytes are derived from osteoblasts but their function although not precisely established probably involves calcium homeostasis and bone cell destruction comparable to osteoclastosis. The term remodeling or bone turnover refers to the sequential processes of resorption and subsequent formation for maintenance of mineral homeostasis. In normal man this remodeling cycle occurs at a particular site about every 3 months. The osteoclasts and osteoblasts which are responsible for remodeling appear to be anatomically linked or coupled in equilibrium. Osteocalcin (OC) acts as a regulator of bone mineralization. It also regulates osteoblast and osteoclast activity. This review article lays emphasis on the structure and interaction of OC with various other molecules; its skeletal effects and therapeutic applications.