Biomarkers in Bone Disease

The bone has the function of supporting the body; the bone is a tissue characterized by its rigidity, hardness, and power of regeneration and repair. The bone has several functions including protection of the vital organs, environment for marrow, mineral reservoir for calcium homeostasis, reservoir of growth factors and cytokines, and taking part in acid–base balance. Bone metabolism is a dynamic and continuous remodeling process that is normally maintained in a tightly coupled balance between resorption of old or injured bone and formation of new bone. Several hormones and factors are involved in bone metabolism, which regulation depends from the complex interaction among them. Considering the various phases of the bone cycle, markers of bone metabolism may be classified either as markers of bone formation, markers of bone resorption, and markers of bone metabolism regulation. The aim of this chapter will be to examine biochemical markers in bone metabolism in order to give readers a guide about the normal physiological process to better understand the mechanisms underlying bone diseases.