Bone remodeling biomarkers of periodontal disease in saliva

ZENI SUSANA NOEMI

JOURNAL OF PERIODONTOLOGY

AMER ACAD PERIODONTOLOGY

Lugar: Chicago; Año: 2009 vol. 80 p. 1565 - 1566

0022-3492

We think that precise concepts of these two bone resorption markers may be of significant value for selecting therapy, monitoring response in treated individuals and predicting risk of bone mass loss and consequently risk of fracture. The sequence of reactions involved in the osteoclastic resorption process of bone is sufficiently important to justified detailed consideration. There are two types of proteolytic enzymes to breakdown the organic matrix of type I collagen, lysosomal cathepsins and matrix metalloproteinases (MMPs) (3). Cathepsin K, in acidic pH, attacks at multiple sites of the type I collagen, including several sites at the helical region (4). Thus the triple helix becomes susceptible for further action of proteolytic enzymes, including MMPs action later in the resorption process at neutral pH (3). Two of these breakdown crosslink peptides, from the carboxy-terminal telopeptide areas of type I collagen, are the CTX and ICTP which are used as bone resorption markers (5). Both markers are produced by different collagenolytic pathway (6).  While, CTX is generated by Cathepsin K, the ICTP is destroyed by this enzyme (7) and generated by metalloproteinases (MMP) such as MMP-9 and -12 (8). Therefore ICTP has been proposed to be called CTX-MMP (5).