C-telopeptide

C-telopeptide pyridinoline cross-links. Sensitive indicators of periodontal tissue destruction

C-telopeptides and related pyridinoline cross-links of bone Type I collagen are sensitive markers of bone resorption in osteolytic diseases such as osteoporosis and osteoarthritis. We have studied the release of C-telopeptide pyridinoline crosslinks of Type I collagen as measures of bone destruction in periodontal disease. Studies in preclinical animal models and humans have demonstrated the relationship between radiographic bone loss and crevicular fluid C-telopeptide levels. We have recently found that C-telopeptide levels correlate strongly with microbial pathogens associated with periodontitis and around endosseous dental implants. Host-modulation of bone-related collagen breakdown has been shown by studies in humans demonstrating that MMP inhibition blocks tissue destruction and release of C-telopeptides in patients with active periodontal disease.

Specific Collagen Peptides Improve Bone Mineral Density and Bone Markers in Postmenopausal Women-A Randomized Controlled Study

Introduction: Investigations in rodents as well as in vitro experiments have suggested an anabolic influence of specific collagen peptides (SCP) on bone formation and bone mineral density (BMD). The goal of the study was to investigate the effect of 12-month daily oral administration of 5 g SCP vs. placebo (CG: control group) on BMD in postmenopausal women with primary, age-related reduction in BMD. Methods: 131 women were enrolled in this randomized, placebo-controlled double-blinded investigation. The primary endpoint was the change in BMD of the femoral neck and the spine after 12 months. In addition, plasma levels of bone markers-amino-terminal propeptide of type I collagen (P1NP) and C-telopeptide of type I collagen (CTX 1)-were analysed. Results: A total of 102 women completed the study, but all subjects were included in the intention-to-treat (ITT) analysis (age 64.3 ㊣ 7.2 years; Body Mass Index, BMI 23.6 ㊣ 3.6 kg/m?; T-score spine -2.4 ㊣ 0.6; T-score femoral neck -1.4 ㊣ 0.5). In the SCP group (n = 66), BMD of the spine and of the femoral neck increased significantly compared to the control group (n = 65) (T-score spine: SCP +0.1 ㊣ 0.26; CG -0.03 ㊣ 0.18; ANCOVA p = 0.030; T-score femoral neck: SCP +0.09 ㊣ 0.24; CG -0.01 ㊣ 0.19; ANCOVA p = 0.003). P1NP increased significantly in the SCP group (p = 0.007), whereas CTX 1 increased significantly in the control group (p = 0.011). Conclusions: These data demonstrate that the intake of SCP increased BMD in postmenopausal women with primary, age-related reduction of BMD. In addition, SCP supplementation was associated with a favorable shift in bone markers, indicating increased bone formation and reduced bone degradation.

Bone turnover: Biology and assessment tools

Bone turnover includes two processes: resorption (removal of old bone) and formation (laying down of new bone). N-terminal propeptide of type I procollagen (PINP) and C-telopeptide of type I collagen (CTX-I) are markers of bone formation and resorption, respectively, that the International Osteoporosis Foundation and the International Federation of Clinical Chemistry recommend for clinical use. Bone turnover markers (BTM) are subject to sources of variability, including feeding (lower resorption) and recent fracture (increased levels of all markers). Controllable patient-related factors should be adapted as much as possible (eg blood collection after an overnight fast) to minimize pre-analytical variability. Uncontrollable factors should be considered in the interpretation of the BTM measurements. BTM do not improve prediction of bone loss or fracture within an individual. In osteoporotic patients, BTM may help to assess the response to anabolic and antiresorptive therapies, to assess compliance to the treatment, or to indicate possible secondary causes of osteoporosis. BTM reflect changes in bone metabolism induced by anti-osteoporotic treatment. Anti-resorptive drugs induce a rapid dose-dependent decrease in bone resorption, whereas bone formation stimulating medications increase the levels of bone formations markers. BTM may be used for monitoring anti-osteoporosis therapy. The expected effect during the anti-resorptive therapy is to decrease the PINP by at least 10 ng/mL and to attain the target level of less than 35 ng/mL. The expected effect during the bone formation-stimulating therapy is to increase the PINP by at least 10 ng/mL and to attain the target level of more than 69 ng/mL.

Assessing the utility of serum C-telopeptide cross-link of type 1 collagen as a predictor of bisphosphonate-related osteonecrosis of the jaw: A systematic review and meta-analysis

Background: The authors of this systematic review and meta-analysis assessed the utility of serum C-telopeptide cross-link of type 1 collagen (sCTX), a biomarker of bone resorption, as a predictor of the development of bisphosphonate-related osteonecrosis of the jaw (BRONJ).
Types of studies reviewed: The authors searched for studies involving adult participants, written in English, and published through January 20, 2016, using the following electronic databases: the Cochrane Library, MEDLINE via PubMed, and Web of Science. They also searched Google Scholar and the reference lists of all eligible trials and reviews. They identified 16 articles that met their inclusion criteria (9 controlled studies and 7 case series). They applied the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews and meta-analyses. They independently extracted data in duplicate, including the characteristics of study participants, risk factors, control groups, and outcomes. They assessed risk of bias, and they resolved any disagreements between review authors through discussion.
Results: A meta-analysis with 9 controlled studies revealed no significant difference in mean sCTX values between patients with BRONJ and control participants (difference in means, -31.417; 95% confidence interval [CI], -91.560 to 28.726; P = .306). A second meta-analysis with 4 studies showed no significant difference in risk of having an sCTX value below 150 picograms per milliliter for patients with BRONJ compared with control participants (risk ratio, 1.892; 95% CI, 0.636-5.626; P = .251).
Conclusions and practical implications: A systematic review of the literature with meta-analysis does not support the use of sCTX levels as a predictor of the development of BRONJ. Further prospective large sample studies are needed to understand the role of sCTX as a predictor for BRONJ.

The relationship between urinary C-Telopeptide fragments of type II collagen, knee joint load, pain, and physical function in individuals with medial knee osteoarthritis

Objective: Considering the osteoarthritis (OA) model that integrates the biological, mechanical, and structural components of the disease, the present study aimed to investigate the association between urinary C-Telopeptide fragments of type II collagen (uCTX-II), knee joint moments, pain, and physical function in individuals with medial knee OA.
Methods: Twenty-five subjects radiographically diagnosed with knee OA were recruited. Participants were evaluated through three-dimensional gait analysis, uCTX-II level, the WOMAC pain and physical function scores, and the 40m walk test. The association between these variables was investigated using Pearson's product-moment correlation, followed by a hierarchical linear regression, controlled by OA severity and body mass index (BMI).
Results: No relationship was found between uCTX-II level and knee moments. A significant correlation between uCTX-II level and pain, physical function, and the 40m walk test was found. The hierarchical linear regression controlling for OA severity and BMI showed that uCTX-II level explained 9% of the WOMAC pain score, 27% of the WOMAC physical function score, and 7% of the 40m walk test.
Conclusion: Greater uCTX-II level is associated with higher pain and reduced physical function and 40m walk test performance in individuals with medial knee OA.