Biochemical markers of bone turnover – uses and limitations

Abstract

Bone turnover markers of resorption and formation are released during the process of bone remodelling. These markers have been extensively studied in a number of therapeutic trials of osteoporosis during the past decade. This has led to better understanding of their physiology, clinical applications and possible ways to optimize analytical techniques. Bone markers can complement the results of bone mineral density in the management of osteoporosis, but their use in clinical practice is challenged by pre-analytical and analytical variability. This review will discuss different types of bone markers, their limitations, use in different metabolic bone diseases and current recommendations from the International Osteoporosis Foundation and the International Federation of Clinical Chemistry and Laboratory Medicine bone marker standards working group.

Bone remodeling markers and bone metastases: From cancer research to clinical implications

“…OC is considered a specific marker of osteoblast function. 10,11 P1NP is derived from extracellular processing of procollagen type I molecule. Procollagen contains amino-and carboxyterminal extensions that are enzymatically cleaved upon procollagen secretion, P1NP and P1CP.…”

“…Procollagen contains amino-and carboxyterminal extensions that are enzymatically cleaved upon procollagen secretion, P1NP and P1CP. 10 PYD and DPD are two nonreducible pyridinium crosslinks that are present in bone collagen, which are released into the circulation upon collagen breakdown either in a free state or Figure 1 Biochemical markers of bone turnover. Blue boxes/arrows represent bone formation markers: bone-specific alkaline phosphatase (BALP); osteocalcin (OC); propeptides of type I procollagen (P1NP and P1CP).…”

“…Since then, different ELISAs have been developed to quantify BALP isoenzyme in serum or heparin plasma. 10 Although reproducible and precise, these immunoassays still retain some crossreactivity with the liver isoenzyme: around 15% with the BALP Ostase immunoassay and 3-10% with the Alphase-B enzyme immunoassay. Therefore, BALP results must be carefully interpreted in patients with liver pathology.…”

Mecanismos intracelulares induzidos por leucotrienos durante a diferenciação osteogênica

“…O colágeno é um elemento importante na estrutura óssea sendo o colágeno tipo I o mais predominante na composição da matriz orgânica. Outras proteínas não colágenas como osteocalcina (OC), glicoproteínas, proteoglicanos, proteínas morfogenéticas ósseas (BMPs) e fatores de crescimento estão presentes em menores quantidades (HLAING, COMPSTON, 2014). Os elementos da matriz inorgânica são capazes de mineralizar a matriz orgânica por meio do cálcio e do fosfato que formam cristais na forma de hidroxiapatita (DATTA et al, 2008;FLORENCIO-SILVA et al, 2015).…”

“…Os marcadores de formação óssea são produzidos por células osteoblásticas ou derivados do metabolismo do procolágeno, já os marcadores de reabsorção são derivados da degradação de moléculas, produtos de osteoclastos ou degradação de colágeno (HLAING, COMPSTON, 2014).…”