Tibolone has estrogenic, progestogenic, and androgenic effects. Although tibolone prevents bone loss, its effects on fractures, breast cancer, and cardiovascular disease are uncertain.
In this randomized study, we assigned 4538 women, who were between the ages of 60 and 85 years and had a bone mineral density T score of −2.5 or less at the hip or spine or a T score of −2.0 or less and radiologic evidence of a vertebral fracture, to receive once-daily tibolone (at a dose of 1.25 mg) or placebo. Annual spine radiographs were used to assess for vertebral fracture. Rates of cardiovascular events and breast cancer were adjudicated by expert panels.
During a median of 34 months of treatment, the tibolone group, as compared wit h the placebo group, had a decreased risk of vertebral fracture, with 70 cases versus 126 cases per 1000 person-years (relative hazard, 0.55; 95% confidence interval [CI], 0.41 to 0.74; P<0.001), and a decreased risk of nonvertebral fracture, with 122 cases versus 166 cases per 1000 person-years (relative hazard, 0.74; 95% CI, 0.58 to 0.93; P = 0.01). The tibolone group also had a decreased risk of invasive breast cancer (relative hazard, 0.32; 95% CI, 0.13 to 0.80; P = 0.02) and colon cancer (relative hazard, 0.31; 95% CI, 0.10 to 0.96; P=0.04). However, the tibolone group had an increased risk of stroke (relative hazard, 2.19; 95% CI, 1.14 to 4.23; P = 0.02), for which the study was stopped in February 2006 at the recommendation of the data and safety monitoring board. There were no significant differences in the risk of either coronary heart disease or venous thromboembolism between the two groups.
Tibolone reduced the risk of fracture and breast cancer and possibly colon cancer but increased the risk of stroke in older women with osteoporosis. (ClinicalTrials. gov number, NCT00519857.)
Alzheimer's disease (AD) is a devastating neurological disease characterized by pathological proteolytic cleavage of tau protein, which appears to initiate death of the neurons. The objective of this study was to investigate whether a proteolytic fragment of the tau protein could serve as blood-based biomarker of cognitive function in AD.
We developed a highly sensitive ELISA assay specifically detecting an A Disintegrin and Metalloproteinase 10 (ADAM10)-generated fragment of tau (Tau-A). We characterized the assay in detail with to respect specificity and reactivity in healthy human serum. We used samples from the Tg4510 tau transgenic mice, which over-express the tau mutant P301L and exhibit a tauopathy with similarities to that observed in AD. We used serum samples from 21 well-characterized Alzheimer's patients, and we correlated the Tau-A levels to cognitive function.
The Tau-A ELISA specifically detected the cleavage sequence at the N-terminus of a fragment of tau generated by ADAM10 with no cross-reactivity to intact tau or brain extracts. In brain extracts from Tg4510 mice compared to wt controls we found 10-fold higher levels of Tau-A (p<0.001), which indicates a pathological relevance of this marker. In serum from healthy individuals we found robust and reproducible levels of Tau-A, indicating that the analyte is present in serum. In serum from AD patients an inverse correlation (R2 = 0.46, p<0.001) between the cognitive assessment score (Mattis Dementia Rating Scale (MDRS)) and Tau-A levels was observed.
Based on the hypothesis that tau is cleaved proteolytically and then released into the blood, we here provide evidence for the presence of an ADAM10-generated tau fragment (Tau-A) in serum. In addition, the levels of Tau-A showed an inverse correlation to cognitive function, which could indicate that this marker is a serum marker with pathological relevance for AD.
Aim: The present study describes the assessment of true formation of type III collagen in different pathologies using a neo-epitope specific competitive Enzyme-linked immunosorbent assay (ELISA) towards the N-terminal propeptide of type III collagen (PRO-C3). Methods: The monoclonal antibody was raised against the N-protease mediated cleavage site of the N-terminal propeptide of type III collagen and a competitive ELISA was developed using the selected antibody. The assay was evaluated in relation to neo-epitope specificity, technical performance, and as a marker for liver fibrosis and muscle mass using the rat carbon tetrachloride (CCl4) model and a study of immobilization induced muscle loss in humans, respectively. Results: The ELISA was neo-epitope specific, technically stable and can be assessed in serum and plasma samples. In the CCl4 liver fibrosis model it was observed that serum PRO-C3 were significantly elevated in rats with liver fibrosis as seen by histology (56% elevated in the highest quartile of total hepatic collagen compared to control rats, p<0.001) and correlated significantly to total hepatic collagen in the diseased rats (r=0.46, p<0.01) and not in control rats, suggesting the pathological origin of the epitope. Human plasma PRO-C3 correlated significantly to muscle mass at baseline (R2=0.44, p=0.036). Conclusion: The developed neo-epitope specific serum ELISA for type III procollagen (PRO-C3) reflects true formation as it is specific for the propeptide cleaved off the intact collagen molecule. In a clinical and in a rodent study we showed that this marker was highly related to liver fibrosis and muscle mass.
Biochemical markers; type III collagen; formation; neo-epitope; liver fibrosis; muscle mass
Extracellular matrix remodelling is a prerequisite for plaque rupture in atherosclerotic lesion. Versican, an extracellular matrix proteoglycan present in normal and atherosclerotic arteries is a substrate for matrix metalloproteinases (MMPs) present in macrophage rich areas. The aim of the current study was to develop an immunoassay to detect a specific MMP-12 derived versican degradation fragment (VCANM) and assess its potential as a biomarker for extracellular matrix remodelling in atherosclerosis. A mouse monoclonal antibody raised against VCANM was used for the development of a competitive ELISA for detection of the fragment in plasma. VCANM was measured in plasma of patients with different levels of heart diseases. Patients experiencing I) acute coronary syndrome, II) stable ischemic heart disease and III) demonstrating high levels of coronary calcium deposits had significantly higher plasma levels of VCANM compared to a control group of individuals with no detectable coronary calcium deposits. VCANM was also detected by immunohistochemistry in coronary artery sections of patients with different degrees of atherosclerosis. VCANM ability to separate patients with atherosclerotic diseases from healthy individuals suggested VCANM as a potential biomarker for the pathological arterial matrix remodelling associated with atherosclerosis.
Versican; acute coronary syndrome; atherosclerosis; biomarker; matrix; remodeling; neo-epitope
Inflammation driven connective tissue turnover is key in rheumatic diseases, such as ankylosing spondylitis (AS). Few biomarkers are available for measuring disease prognosis or the efficacy of interventions applied in these tissue-related conditions. Type II collagen is the primary structural protein of cartilage and type III collagen of connective tissues, and obvious targets for the collagenalytic, which increase during tissue inflammation. The objective of the study was to investigate the diagnostic and prognostic utility of cartilage, C2M, and synovial, C3M, turnover biomarkers in AS. Serum samples were retrieved from patients suffering from AS (n = 103), RA (n = 47) and healthy controls (n = 56). AS progressors were defined as having new vertebral syndesmophytes or more that 3 unit change in mSASSS over a two-year period. Type II collagen degradation markers in serum were measured by the C2M ELISA, and type III collagen degradation by the C3M ELISA. Logistic regression and dichotomized decision tree were used to analyze the prognostic value of the markers individually or in combination. Both C2M and C3M levels were significantly higher in RA patients than in healthy controls (p<0.0001). Diagnostic utility was analyzed by ROC and areas under the curve (AUCs) were 72% and 89% for C2M and C3M, respectively. Both C2M and C3M, were significantly higher in serum samples from AS patient than from healthy controls (p<0.0001). The AUCs of C2M and C3M, respectively, were 70% and 81% for AS. A combination of C2M and C3M, dichotomized according to best cut-offs for individual markers, could correctly identify 80% of the progressors and 61% of the non-progressors. The present study is the first to show that specific biomarkers of cartilage and connective tissue degradation facilitate both diagnosis and prediction of progression of RA and AS.
Aim: To investigate whether increased levels of vimentin citrullinated peptides identified by MS in articular cartilage can be measured in pathologies other than rheumatoid arthritis and be utilised for diagnostic purposes. Methods: A monoclonal antibody against the sequence RLRSSVPGV-citrulline (VICM) was developed and evaluated in a carbon tetrachloride (CCl4) (n=52 + 28 controls) rat model of liver fibrosis and two clinical cohorts of adult patients with hepatitis C (HCV) (n=92) and non-alcoholic fatty liver disease (NAFLD) (n=62), and compared to healthy controls. Results: In CCl4-treated rats, mean systemic VICM levels increased 31% at week 12 (176 ng/mL, P<0.001), 41.7% at weeks 16 (190 ng/mL, P<0.001), 49.2% at weeks 20 (200 ng/ml, P<0.001), compared to controls (134 ng/mL). VICM levels correlated with total hepatic collagen determined by Sirius red staining of rat livers (r=0.75, P<0.05). In the HCV cohort, when stratified according to the METAVIR F score, VICM levels were 63% higher in F0 (632 ng/mL ±75, p<0.05), 54% in F1 (597 ng/mL ±41.3, p<0.05) and 62% in F2 (628 ng/mL ±59, p<0.05) all compared to controls. In the NAFLD cohort, VICM levels were 20.6% higher in F0 (339 ±12 ng/mL, P<0.05), 23.8% in F1 (348 ±12 ng/mL, P<0.05) and 28.8% in F2 (362 ±25 P<0.05). Conclusion: We demonstrated increased serological levels of citrullinated and MMP degraded vimentin in an animal model of liver fibrosis and in early fibrosis associated with HCV and NAFLD patients. These data suggest that citrullinated and MMP degraded proteins are also present in liver fibrosis.
Biomarker; citrulline; hepatitis C; NAFLD
Titin is a muscle-specific protein found in cardiac and skeletal muscles which is responsible for restoring passive tension. Levels and functioning of titin have been shown to be affected by cardiac damage. Due to the inherent difficulty of measuring titin levels in vivo in a clinical setting, we aimed to develop an assay that could reliably measure fragments of degraded titin in serum and potentially be used in the assessment of cardiac muscle damage.
A competitive ELISA was developed to specifically measure levels of the titin sequence 12670’ NVTVEARLIK 12679’, derived by the degradation of titin by matrix metalloproteinase (MMP)-12. Serum samples from 90 individuals were divided into 3 equally sized groups. One group had been diagnosed with acute myocardial infarction (AMI) while the remaining two were asymptomatic individuals either with CT-scan signs of coronary calcium (CT-plusCa) or without coronary calcium (CT-noCa).
Mean geometric levels of the titin fragment in the CT-noCa group were 506.5 ng/ml (±43.88). The CT-plusCa group showed 50.6% higher levels of the marker [763 ng/ml (±90.14)] (P < 0.05). AMI patients showed 56.3% higher levels [792 ng/ml (±149)] (P < 0.05).
The titin-12670 fragment is present in both individuals with undiagnosed and diagnosed CVD. The statistically significant increase in level of the marker in the AMI group is indicative that this neoepitope biomarker may be a useful serological marker in AMI.
Titin; CVD; MMP-12; Cardiovascular; Acute myocardial infarction; Biomarker; Neoepitope
Abdominal aortic calcifications (AACs) correlate strongly with coronary artery calcifications and can be predictors of cardiovascular mortality. We investigated whether size, shape, and distribution of AACs are related to mortality and how such prognostic markers perform compared to the state-of-the-art AC24 marker introduced by Kauppila. Methods. For 308 postmenopausal women, we quantified the number of AAC and the percentage of the abdominal aorta that the lesions occupied in terms of their area, simulated plaque area, thickness, wall coverage, and length. We analysed inter-/intraobserver reproducibility and predictive ability of mortality after 8-9 years via Cox regression leading to hazard ratios (HRs). Results. The coefficient of variation was below 25% for all markers. The strongest individual predictors were the number of calcifications (HR = 2.4) and the simulated area percentage (HR = 2.96) of a calcified plaque, and, unlike AC24 (HR = 1.66), they allowed mortality prediction also after adjusting for traditional risk factors. In a combined Cox regression model, the strongest complementary predictors were the number of calcifications (HR = 2.76) and the area percentage (HR = −3.84). Conclusion. Morphometric markers of AAC quantified from radiographs may be a useful tool for screening and monitoring risk of CVD mortality.
Abdominal aortic calcifications (AAC) predict cardiovascular mortality. A new scoring model for AAC, the Morphological Atherosclerotic Calcification Distribution (MACD) index may contribute with additional information to the commonly used Aortic Calcification Severity (AC24) score, when predicting death from cardiovascular disease (CVD). In this study we investigated associations of MACD and AC24 with traditional metabolic-syndrome associated risk factors at baseline and after 8.3 years follow-up, to identify biological parameters that may account for the differential performance of these indices.
Three hundred and eight healthy women aged 48 to 76 years, were followed for 8.3 ± 0.3 years. AAC was quantified using lumbar radiographs. Baseline data included age, weight, blood pressure, blood lipids, and glucose levels. Pearson correlation coefficients were used to test for relationships.
At baseline and across all patients, MACD correlated with blood glucose (r2 = 0.1, P< 0.001) and to a lesser, but significant extent with traditional risk factors (p < 0.01) of CVD. In the longitudinal analysis of correlations between baseline biological parameters and the follow-up calcification assessment using radiographs we found LDL-cholesterol, HDL/LDL, and the ApoB/ApoA ratio significantly associated with the MACD (P< 0.01). In a subset of patients presenting with calcification at both baseline and at follow-up, all cholesterol levels were significantly associated with the MACD (P< 0.01) index. AC24 index was not correlated with blood parameters.
Patterns of calcification identified by the MACD, but not the AC24 index, appear to contain useful biological information perhaps explaining part of the improved identification of risk of cardiovascular death of the MACD index. Correlations of MACD but not the AC24 with glucose levels at baseline suggest that hyperglycemia may contribute to unique patterns of calcification indicated by the MACD.
Cardiovascular disease; aortic calcification; risk factors; AAC24
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease associated with potentially debilitating joint inflammation, as well as altered skeletal bone metabolism and co-morbid conditions. Early diagnosis and aggressive treatment to control disease activity offers the highest likelihood of preserving function and preventing disability. Joint inflammation is characterized by synovitis, osteitis, and/or peri-articular osteopenia, often accompanied by development of subchondral bone erosions, as well as progressive joint space narrowing. Biochemical markers of joint cartilage and bone degradation may enable timely detection and assessment of ongoing joint damage, and their use in facilitating treatment strategies is under investigation. Early detection of joint damage may be assisted by the characterization of biochemical markers that identify patients whose joint damage is progressing rapidly and who are thus most in need of aggressive treatment, and that, alone or in combination, identify those individuals who are likely to respond best to a potential treatment, both in terms of limiting joint damage and relieving symptoms. The aims of this review are to describe currently available biochemical markers of joint metabolism in relation to the pathobiology of joint damage and systemic bone loss in RA; to assess the limitations of, and need for additional, novel biochemical markers in RA and other rheumatic diseases, and the strategies used for assay development; and to examine the feasibility of advancement of personalized health care using biochemical markers to select therapeutic agents to which a patient is most likely to respond.
Aortic calcification is a major risk factor for death from cardiovascular disease. We investigated the relationship between mortality and the composite markers of number, size, morphology and distribution of calcified plaques in the lumbar aorta.
308 postmenopausal women aged 48-76 were followed for 8.3 ± 0.3 years, with deaths related to cardiovascular disease, cancer, or other causes being recorded. From lumbar X-rays at baseline the number (NCD), size, morphology and distribution of aortic calcification lesions were scored and combined into one Morphological Atherosclerotic Calcification Distribution (MACD) index. The hazard ratio for mortality was calculated for the MACD and for three other commonly used predictors: the EU SCORE card, the Framingham Coronary Heart Disease Risk Score (Framingham score), and the gold standard Aortic Calcification Severity score (AC24) developed from the Framingham Heart Study cohorts.
All four scoring systems showed increasing age, smoking, and raised triglyceride levels were the main predictors of mortality after adjustment for all other metabolic and physical parameters. The SCORE card and the Framingham score resulted in a mortality hazard ratio increase per standard deviation (HR/SD) of 1.8 (1.51-2.13) and 2.6 (1.87-3.71), respectively. Of the morphological x-ray based measures, NCD revealed a HR/SD >2 adjusted for SCORE/Framingham. The MACD index scoring the distribution, size, morphology and number of lesions revealed the best predictive power for identification of patients at risk of mortality, with a hazard ratio of 15.6 (p < 0.001) for the 10% at greatest risk of death.
This study shows that it is not just the extent of aortic calcification that predicts risk of mortality, but also the distribution, shape and size of calcified lesions. The MACD index may provide a more sensitive predictor of mortality from aortic calcification than the commonly used AC24 and SCORE/Framingham point card systems.
We report the safety findings from a 3-year phase 3 study (NCT00205777) of bazedoxifene, a novel selective estrogen receptor modulator under development for the prevention and treatment of postmenopausal osteoporosis.
Healthy postmenopausal osteoporotic women (N = 7,492; mean age, 66.4 years) were randomized to daily doses of bazedoxifene 20 or 40 mg, raloxifene 60 mg, or placebo for 3 years. Safety and tolerability were assessed by adverse event (AE) reporting and routine physical, gynecologic, and breast examination.
Overall, the incidence of AEs, serious AEs, and discontinuations due to AEs in the bazedoxifene groups was not different from that seen in the placebo group. The incidence of hot flushes and leg cramps was higher with bazedoxifene or raloxifene compared with placebo. The rates of cardiac disorders and cerebrovascular events were low and evenly distributed among groups. Venous thromboembolic events, primarily deep vein thromboses, were more frequently reported in the active treatment groups compared with the placebo group; rates were similar with bazedoxifene and raloxifene. Bazedoxifene showed a neutral effect on the breast and an excellent endometrial safety profile. The incidence of fibrocystic breast disease was lower with bazedoxifene 20 and 40 mg versus raloxifene or placebo. Reductions in total and low-density lipoprotein levels and increases in high-density lipoprotein levels were seen with bazedoxifene versus placebo; similar results were seen with raloxifene. Triglyceride levels were similar among groups.
Bazedoxifene showed a favorable safety and tolerability profile in women with postmenopausal osteoporosis.
Trial registration number: NCT00205777; Trial registration date: September 16, 2005
Proteolytic degradation of Type I Collagen by proteases may play an important role in remodeling of atherosclerotic plaques, contributing to increased risk of plaque rupture.
The aim of the current study was to investigate whether human macrophage foam cells degrade the extracellular matrix (ECM) of atherosclerotic plaques by cathepsin K mediated processes.
We 1) cultured human macrophages on ECM and measured cathepsin K generated fragments of type I collagen (C-terminal fragments of Type I collagen (CTX-I) 2) investigated the presence of CTX-I in human coronary arteries and 3) finally investigated the clinical potential by measuring circulating CTX-I in women with and without radiographic evidence of aortic calcified atherosclerosis.
Immune-histochemistry of early and advanced lesions of coronary arteries demonstrated co-localization of Cathepsin-K and CTX-I in areas of intimal hyperplasia and in shoulder regions of advanced plaques. Treatment of human monocytes with M-CSF or M-CSF+LDL generated macrophages and foam cells producing CTX-I when cultured on type I collagen enriched matrix. Circulating levels of CTX-I were not significantly different in women with aortic calcifications compared to those without.
Human macrophage foam cells degrade the atherosclerotic plaques though cathepsin K mediated processes, resulting in increase in levels of CTX-I. Serum CTX-I was not elevated in women with aortic calcification, likely due to the contribution of CTX-I from osteoclastic bone resorption which involves Cathepsin-K. The human macrophage model system may be used to identify important pathway leading to excessive proteolytic plaque remodeling and plaque rupture.
We report a patient with Q fever endocarditis in a settlement in eastern Greenland (Isortoq, Ammassalik area). Likely animal sources include sled dogs and seals. Q fever may be underdiagnosed in Arctic areas but may also represent an emerging infection.
Q fever; Coxiella burnetii; endocarditis; bacteria; Greenland; Arctic; Inuit; dispatch
At present, no disease-modifying osteoarthritis drugs (DMOADS) are approved by the FDA (US Food and Drug Administration); possibly partly due to inadequate trial design since efficacy demonstration requires disease progression in the placebo group. We investigated whether combinations of biochemical and magnetic resonance imaging (MRI)-based markers provided effective diagnostic and prognostic tools for identifying subjects with high risk of progression. Specifically, we investigated aggregate cartilage longevity markers combining markers of breakdown, quantity, and quality.
The study included healthy individuals and subjects with radiographic osteoarthritis. In total, 159 subjects (48% female, age 56.0 ± 15.9 years, body mass index 26.1 ± 4.2 kg/m2) were recruited. At baseline and after 21 months, biochemical (urinary collagen type II C-telopeptide fragment, CTX-II) and MRI-based markers were quantified. MRI markers included cartilage volume, thickness, area, roughness, homogeneity, and curvature in the medial tibio-femoral compartment. Joint space width was measured from radiographs and at 21 months to assess progression of joint damage.
Cartilage roughness had the highest diagnostic accuracy quantified as the area under the receiver-operator characteristics curve (AUC) of 0.80 (95% confidence interval: 0.69 to 0.91) among the individual markers (higher than all others, P < 0.05) to distinguish subjects with radiographic osteoarthritis from healthy controls. Diagnostically, cartilage longevity scored AUC 0.84 (0.77 to 0.92, higher than roughness: P = 0.03). For prediction of longitudinal radiographic progression based on baseline marker values, the individual prognostic marker with highest AUC was homogeneity at 0.71 (0.56 to 0.81). Prognostically, cartilage longevity scored AUC 0.77 (0.62 to 0.90, borderline higher than homogeneity: P = 0.12). When comparing patients in the highest quartile for the longevity score to lowest quartile, the odds ratio of progression was 20.0 (95% confidence interval: 6.4 to 62.1).
Combination of biochemical and MRI-based biomarkers improved diagnosis and prognosis of knee osteoarthritis and may be useful to select high-risk patients for inclusion in DMOAD clinical trials.
To investigate the influence of water intake and dose timing on the pharmacokinetic and pharmacodynamic parameters of an oral formulation of salmon calcitonin (sCT).
The study was a randomized, partially-blind, placebo-controlled, single dose, exploratory crossover phase I study. 56 healthy postmenopausal women were randomly assigned to receive five treatments. The treatments comprised a combination of study medication (SMC021 (0.8 mg sCT + 200 mg 5-CNAC), SMC021 placebo, or 200 IU Miacalcic® NS nasal spray), water volume given with the tablet (50 or 200 ml water), and time between dosing and meal (10, 30, or 60 minutes pre-meal). Plasma sCT levels and changes in the bone resorption (C-terminal telopeptide of collagen type I) was investigated. Trial regristration
Oral delivery of 0.8 mg of sCT with 50 ml of water compared to that with 200 ml water resulted in a two-fold increase in maximum concentration (Cmax and AUC0–4) of plasma sCT but comparable time to reach maximum concentration (Tmax). The sCT AUC0–4 with 50 ml of water was 4-fold higher than that obtained with nasal calcitonin. The increased absorption of sCT resulted in increased efficacy demonstrated by AUC of the relative change of serum CTX-I measured in the 6 hours post dosing.
0.8 mg sCT with 50 ml of water taken 30 and 60 minutes prior to meal time resulted in optimal pharmacodynamic and pharmacokinetic parameters. The data suggest that this novel oral formulation may have improved absorption and reduction of bone resorption compared to that of the nasal form.
Breast and prostate cancer patients often develop lesions of locally high bone turnover, when the primary tumor metastasizes to the bone causing an abnormal high bone resorption at this site. The objective of the present study was to determine whether local increased bone turnover in breast and prostate cancer patients is associated with an increase in cartilage degradation and to test in vitro whether osteoclasts or cathepsin K alone generate CTXII from human bone.
The study included 132 breast and prostate cancer patient, where presence of bone metastases was graded according to the Soloway score. Total bone resorption (CTXItotal) and cartilage degradation (CTXII) were determined.
Breast and prostate cancer patients with bone metastases revealed significant increased levels of CTXItotal at Soloway scores 1 and higher compared to patients without bone metastases (p < 0.001). CTXII was statistically elevated at score 3 and 4 (p < 0.01). CTXII/CTXItotal significantly decreased at score 3 and 4 (p < 0.001). Levels of CTXItotal, CTXII and CTXII/CTXItotal changed +900%, +130%, and -90%, respectively at Soloway score 4 compared to score 0. The in vitro experiments revealed that osteoclasts released CTXI fragments but not CTXII from bone specimens. The same was observed for cathepsin K.
Data suggest that an uncoupling between bone resorption and cartilage degradation occurs in breast and lung cancer patient.
Physiological and pathophysiological cartilage turnover may coexist in articular cartilage. The distinct enzymatic processes leading to irreversible cartilage damage, compared with those needed for continuous self-repair and regeneration, remain to be identified. We investigated the capacity of repair of chondrocytes by analyzing their ability to initiate an anabolic response subsequent to three different levels of catabolic stimulation.
Cartilage degradation was induced by oncostatin M and tumour necrosis factor in articular cartilage explants for 7, 11, or 17 days. The catabolic period was followed by 2 weeks of anabolic stimulation (insulin growth factor-I). Cartilage formation was assessed by collagen type II formation (PIINP). Cartilage degradation was measured by matrix metalloproteinase (MMP) mediated type II collagen degradation (CTX-II), and MMP and aggrecanase mediated aggrecan degradation by detecting the 342FFGVG and 374ARGSV neoepitopes. Proteoglycan turnover, content, and localization were assessed by Alcian blue.
Catabolic stimulation resulted in increased levels of cartilage degradation, with maximal levels of 374ARGSV (20-fold induction), CTX-II (150-fold induction), and 342FFGVG (30-fold induction) (P < 0.01). Highly distinct protease activities were found with aggrecanase-mediated aggrecan degradation at early stages, whereas MMP-mediated aggrecan and collagen degradation occurred during later stages. Anabolic treatment increased proteoglycan content at all time points (maximally, 250%; P < 0.001). By histology, we found a complete replenishment of glycosaminoglycan at early time points and pericellular localization at an intermediate time point. In contrast, only significantly increased collagen type II formation (200%; P < 0.01) was observed at early time points.
Cartilage degradation was completely reversible in the presence of high levels of aggrecanase-mediated aggrecan degradation. After induction of MMP-mediated aggrecan and collagen type II degradation, the chondrocytes had impaired repair capacity.
A variety of factors contribute to the development of cognitive impairment in elderly people. Previous studies have focused upon a single or a few risk factors. In this study we assessed and compared the significance of a wide variety of potential risk factors for cognitive impairment in postmenopausal women.
A total of 208 pairs of elderly women (mean age = 73.2 years) were examined in a cross-sectional case-control study. Each pair consisted of a case (with impaired cognition) and a control subject matched by age and educational status. Cognitive functions were determined using a modified version of the Blessed test. Participants were also subjected to a general clinical examination and they were interviewed to collect information on lifestyle practices and comorbid disorders. Genotypes for the apolipoprotein E (APOE) epsilon4, catechol-O-methyltransferase (COMT) Val/Met, and brain-derived neurotropic growth factor (BDNF) Val/Met polymorphisms were determined. Data were analyzed by conditional logistic regression.
We identified a set of risk factors for age-related cognitive impairment. A statistical model for assessment of the importance of these factors was constructed. The factors in this model were physical exercise (odds ratio [OR] = 0.50, 95% confidence interval [CI] = 0.32–0.78), regular alcohol consumption (OR = 0.49, 95% CI = 0.29–0.83), metabolic syndrome (OR = 2.83, 95% CI = 1.26–6.39), depression (OR = 3.24, 95% CI = 1.28–8.22), and the APOE epsilon4 allele (OR = 1.76, 95% CI = 1.09–2.83). Also COMT genotype was present as a risk factor in the statistical model (p = 0.08).
Lifestyle risk factors, comorbid disorders, and genetic factors contribute to development of age-related cognitive impairment. The two former groups of risk factors appear to be particular important in this respect.
age-related cognitive impairment; risk factors; lifestyle choices; comorbid disorders; genetic susceptibility
Fragments of collagen type I containing the epitope AHDGGR (CTX) are generated during bone resorption. The aspartyl-glycine (DG) site within CTX is synthesised in the L-aspartyl peptide (αL) form, but converts to the age-modified forms L-isoaspartyl peptide (βL) and D-aspartyl peptide (αD) over time. The purpose of the present study was to test the ability of the various CTX forms to identify breast cancer patients with bone metastases and to investigate whether such patients had an altered CTX excretion pattern.
In this cross-sectional study we compared CTX excretion in healthy premenopausal and postmenopausal women with CTX levels in patients with breast cancer. The breast cancer cohort comprised eight hypercalcemic patients with bone metastases (HC+), 100 normocalcemic patients with bone metastases (NC+) and 15 normocalcemic patients without bone metastases (NC-).
In HC+ patients and NC+ patients, the excretion of αL CTX was highly increased compared with NC- patients (P < 0.01), with Z scores of 3.4 and 2.0, respectively. The excretion of the age-modified forms (βL and αD CTX) was less increased in HC+ patients and in NC+ patients as compared with NC- patients, with Z scores of 2.2 and 1.0, respectively, for βL CTX, and of 1.6 and 0.8, respectively, for αD CTX.
Assays for the various isoforms of CTX have different sensitivities to identify patients affected by bone metastases. The αL CTX isoform reflecting resorption of young bone appeared to provide the best differentiation of patients affected by breast cancer-induced bone metastases. In conclusion, patients affected by metastatic bone disease present an altered excretion pattern of CTX isoforms.
bone metastases; bone resorption; bone turnover; biomarkers; isomerisation
The frequency of epileptic seizures was observed in a controlled therapeutic trial on 23 epileptic inpatients before and after treatment with vitamin D2 or placebo in addition to anticonvulsant drugs. The number of seizures was reduced during treatment with vitamin D2 but not with placebo. The effect was unrelated to changes in serum calcium or magnesium. The results may support the concept that epileptics should be treated prophylactically with vitamin D.
The bone mineral content (B.M.C.) in both forearms (related to total body calcium) was measured by photon absorptiometry for a controlled therapeutic trial in a representative sample of epileptic outpatients, comprising 226 patients treated with one or two major anticonvulsant drugs (phenytoin, phenobarbitone, primidone).
Initially the mean B.M.C. value for all epileptic patients was 87% of normal. During treatment with 2,000 international units of vitamin D2 daily for three months an average B.M.C. increase of 4% was found, whereas the B.M.C. values remained unchanged in the placebo group and in the control groups. The incidence of hypocalcaemia and raised serum alkaline phosphatase was 12% and 43% respectively. The biochemical indices of osteomalacia were related to B.M.C. These results indicate that epileptic patients should be closely supervised for the occurrence of anticonvulsant osteomalacia, and, possibly, receive prophylactic treatment with vitamin D.
The bone mineral mass was estimated by photon absorptiometry in 23 epileptic patients on long-term treatment with phenytoin and in 20 normal subjects before and during treatment with vitamin D or placebo.
Initially, subnormal values of bone mineral mass were found in the epileptic patients. The group of epileptic patients treated with vitamin D showed a significant increase in bone mineral mass. The group of epileptic patients treated with placebo and the normal subjects treated with vitamin D or placebo showed no change in bone mineral mass.
The bone mineral content was measured in 10 epileptic patients on long-term treatment with phenytoin before and during treatment with vitamin D. None of the patients showed biochemical signs of osteomalacia. Initially subnormal values for bone mineral content were found, which increased significantly during treatment. The results suggest the occurrence of latent osteomalacia in a fairly high proportion of epileptic patients on anticonvulsants.