Utilization and Reference Values of Bone Turnover Markers: Osteocalcin and Procollagen Type 1 N- Propeptide
Abstrakt
All body bones undergo continual remodeling. This process consists of bone resorption and bone formation which are closely coupled actions.
Changes in bone tissue are accompanied by changes of biochemical markers. Plasma (and/or urine) concentration of these markers depends on bone resorption/formation activity, i.e., bone turnover rate.
Osteocalcin is important noncollagenous proteinin bone matrix, synthetized by osteoblasts and osteocytes. It is a good marker of bone turnover.
Its undercarboxylated form has a role in regulation of energy metabolism. Osteocalcin is also involved in biosynthesis of testosterone or neurotransmitter production.
Procollagen type 1 N-propeptide is a aminoterminal part of procollagen precursor cleaved by proteases during bone formation process. Its serum concentration is significantly related to newly formed collagen.
Procollagen type 1 N-propeptide is supposed to be the most reliable biochemical marker of bone formation at present time. Reference values of both laboratory markers for central European population of children and adolescents are presented, and some data about reference intervals in adults from different ethnic groups are mentioned.