C-telopeptide

Henkel, W. (1996). Cross-link analysis of the C-telopeptide domain from type III collagen. Biochem. J. 318, 497-503. 

B8. Bonde, M., Garnero, P., Fledelius, C., Qvist, P., Delmas, P. D., and Christiansen, C., Measurement of bone degradation products in serum using antibodies reactive with an isomerized form of an 8 aminoacid sequence of the C-telopeptide of type collagen I. J. Bone Miner. Res. 12,1028—1034 (1997). 

Clinical PK/PD Calcitonin has a well-established mechanism of action published literature supports that salmon calcitonin, mediated through calcitonin receptors located on osteoclasts, inhibits bone resorption, thereby increasing bone mineral density. Since serum beta-CTx (C-telopeptides of type 1 collagen, corrected for creatinine) is a recognized marker of bone resorption, the effect of administered salmon calcitonin on serum beta-CTx is considered to be an adequate surrogate for pharmacodynamic comparisons. 

Widespread osteosclerosis, accompanied by increased serum concentrations of osteocalcin and C telopeptide, developed in a 56-year-old man who took indinavir 800 mg tds for 27 months (36). 

Bone markers are used to assess bone turnover (resorption or formation) in patients with osteoporosis. This testing is useful for identifying osteoporotic individuals with elevated bone resorption and for predicting and assessing the response to therapy. Markers of bone resorption include collagen cross-finks (N telopeptide, deoxypyridinoline, or C-telopeptide). Because bone resorption and formation are coupled, markers of bone formation (BAP and serum osteo-... 

Laboratory and other findings include increased markers of bone turnover, and abnormal radiographs and bone scans. The most common finding leading to the diagnosis of Paget s disease is increased serum ALP (up to tenfold). Increases in markers of bone resorption (N-telopeptide, deoxypyridinohne, and C-telopeptide) reflect the osteoclas-... 

Bone resorption markers are Listed in Box 49-5. N- and C-telopeptides of type I collagen (NTx and CTx) and deoxypyridinoline are most frequently measured. Other markers include serum tartrate-resistant acid phosphatase (TRAP) and hydroxyproline. Bone resorption markers, apart from TRAP, were initially measured in urine. More recently, methods using serum have been developed for a number of these analytes including N- and C-telopeptides. 

Figure 49-24 Pyridtnium cross-links and N-telopeptides of type I collagen. Cross-links occur at two intermolecular sites in the collagen fibril (i) two N-telopeptides are linked to a helical site at residue 930, and (2) two C-te opeptides are linked to helical residue 87.The location and amino acid sequence of the N-telopeptide (NTx) and the C-telopeptide (CTx) and the structures of the free pyridinium cross-links (pyridinoline and deoxypyridinoline) are shown.

Intermolecular cross-linking sites have been located that form the pyridinium cross-links in type I collagen (Figure 49-24). Two N-telopeptide sites are linked to the helical site at amino acid 930 (N-telopeptide) or two C-telopeptides are linked to the helical site amino acid 87 (C-telopeptide). 

Bonde M, Fledelius C, Qvist P, Christiansen C. Coated-tube radioimmunoassay for C-telopeptides of type I collagen to assess bone resorption. Clin Chem 1996 42 1639-44. 

Pedersen BJ, Ravn P, Bonde M. Type I collagen C-telopeptide degradation products as bone resorption markers. J Chn Ligand Assay 1998 21 118-27. 

Collagen type 11 C telopeptide C propeptide of type 11 collagen (CPU)... 

Another approach was presented in work of Bhowmik and coworkers [233] who performed molecular dynamics (MD) and steered MD (SMD) simulations in order to understand the loadcarrying behaviour of Col in the proximity of HAp. The Col molecule is helical overall with non-helical ends that are N- or C-telopeptides. The Col molecule with telopeptides interacts with specific surfaces of mineralized HAp (Fig. 21). 

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