Serum Levels Of Carboxy-terminal Telopeptide Research Articles

Adiponectin attenuates profibrotic extracellular matrix remodeling following cardiac injury by up-regulating matrix metalloproteinase 9 expression in mice.

Adiponectin (APN) is a multifunctional adipocytokine that inhibits myocardial fibrosis, dilatation, and left ventricular (LV) dysfunction after myocardial infarction (MI). Coxsackievirus B3 (CVB3) myocarditis is associated with intense extracellular matrix (ECM) remodeling which might progress to dilated cardiomyopathy. Here, we investigated in experimental CVB3 myocarditis whether APN inhibits adverse ECM remodeling following cardiac injury by affecting matrix metalloproteinase (MMP) expression. Cardiac injury was induced by CVB3 infection in APN knockout (APN‐KO) and wild‐type (WT) mice. Expression and activity of MMPs was quantified by qRT‐PCR and zymography, respectively. Activation of protein kinases was assessed by immunoblot. In cardiac myocytes and fibroblasts APN up‐regulates MMP‐9 expression via activation of 5′ adenosine monophosphate‐activated protein kinase (AMPK) and extracellular signal‐regulated kinase (ERK)1/2 which function as master regulators of inflammation‐induced MMP‐9 expression. Correspondingly, APN further increased up‐regulation of MMP‐9 expression triggered by tumor necrosis factor (TNF)α, lipopolysaccharide (LPS) and R‐848 in cardiac fibroblasts. In vivo, compared to WT mice cardiac MMP‐9 activity and serum levels of carboxy‐terminal telopeptide of type I collagen (ICTP) were attenuated in APN‐KO mice in subacute (day 7 p.i.) CVB3 myocarditis. Moreover, on day 3 and day 7 post CVB3 infection splenic MMP‐9 expression was diminished in APN‐KO mice correlating with attenuated myocardial immune cell infiltration in subacute CVB3 myocarditis. These results indicate that APN attenuates adverse cardiac remodeling following cardiac injury by up‐regulating MMP‐9 expression in cardiac and immune cells. Thus, APN mediates intensified collagen cleavage that might explain inhibition of LV fibrosis and dysfunction.

Serum carboxy-terminal telopeptide of type I collagen (I-CTP) is predictive of clinical outcome in peripheral artery disease patients following endovascular therapy.

Peripheral artery disease (PAD) is a risk factor for the development of heart failure and mortality. The serum levels of carboxy-terminal telopeptide of type I collagen (I-CTP), a marker for collagen degradation derived from the extracellular matrix of vascular and myocardial tissue, is reportedly a useful marker for cardiac events in patients with heart disease. However, it remains unclear whether I-CTP can predict poor clinical outcome in patients with PAD. Serum I-CTP was measured in 246 consecutive PAD patients who underwent endovascular therapy. Patients were prospectively followed during a median follow-up period of 887days with the end points of major adverse cardiovascular events (MACE). I-CTP was significantly higher in patients with critical limb ischemia than those without. A multivariate Cox proportional hazard analysis revealed that I-CTP was an independent predictor of MACE after adjusting for confounding factors. Patients were stratified into three groups based on I-CTP level tertile, and those with third tertile had higher levels of brain natriuretic peptide levels and high-sensitivity C-reactive protein compared to the other two groups. Kaplan-Meier analysis demonstrated that patients in the highest tertile of I-CTP also had the greatest risk of MACE. The net reclassification index significantly improved with the addition of I-CTP to basic predictors. I-CTP is a reliable marker and indicator for MACE in patients with PAD.

Dehydroepiandrosterone sulfate and bone resorption rates as reflected by serum levels of C-terminal telopeptide of type I collagen: A study in healthy men

Sex steroid hormones contribute to the physiological regulation of bone turnover in males. To address this issue, we investigated serum estradiol (E2), total testosterone (T), and DHEAS concentrations, along with serum levels of carboxy-terminal telopeptide of type I collagen (sCTx), in a sample of 76 healthy men aged 23 to 87. The concentration of sCTx declined with age. Both T and DHEAS, at variance with E2, showed a significant age-related decline. T, DHEAS and sCTx significantly (p<0.01) correlated with each other. DHEAS and T were significantly associated after correcting for age (r=0.35, p=0.002) or body mass index (r=0.65, p<0.0001). DHEAS, but not T, significantly correlated with sCTx after correcting for age (r=0.26, p=0.026, and r=0.20, p=0.08, respectively). Stepwise multiple regression analysis showed that only DHEAS (but not T or E2) was a significant independent predictor of sCTx (p=0.0001). Our results show that adrenal androgens play a crucial role in regulating bone resorption in aging men.