Effects of an Intervention with Selenium and Coenzyme Q10 on Five Selected Age-Related Biomarkers in Elderly Swedes Low in Selenium: Results That Point to an Anti-Ageing Effect-A Sub-Analysis of a Previous Prospective Double-Blind Placebo-Controlled Randomised Clinical Trial

Background: Ageing is associated with cardiovascular disease (CVD). As no single biomarker reflects the full ageing process, we aimed to investigate five CVD- and age-related markers and the effects of selenium and coenzyme Q10 intervention to elucidate the mechanisms that may influence the course of ageing. Methods: This is a sub-study of a previous prospective double-blind placebo-controlled randomized clinical trial that included 441 subjects low in selenium (mean age 77, 49% women). The active treatment group (n = 220) received 200 µg/day of selenium and 200 mg/day of coenzyme Q10, combined. Blood samples were collected at inclusion and after 48 months for measurements of the intercellular adhesion molecule (ICAM-1), adiponectin, leptin, stem cell factor (SCF) and osteoprotegerin (OPG), using ELISAs. Repeated measures of variance and ANCOVA evaluations were used to compare the two groups. In order to better understand and reduce the complexity of the relationship between the biomarkers and age, factor analyses and structural equation modelling (SEM) were performed, and a structural model is presented. Results: Correlation analyses of biomarker values at inclusion in relation to age, and relevant markers related to inflammation, endothelial dysfunction and fibrosis, demonstrated the biomarkers' association with these pathological processes; however, only ICAM1 and adiponectin were directly correlated with age. SEM analyses showed, however, that the biomarkers ICAM-1, adiponectin, SCF and OPG, but not leptin, all had significant associations with age and formed two independent structural factors, both significantly related to age. While no difference was observed at inclusion, the biomarkers were differently changed in the active treatment and placebo groups (decreasing and increasing levels, respectively) at 48 months (p ≤ 0.02 in all, adjusted), and in the SEM model, they showed an anti-ageing impact. Conclusions: Supplementation with selenium/Q10 influenced the analysed biomarkers in ways indicating an anti-ageing effect, and by applying SEM methodology, the interrelationships between two independent structural factors and age were validated.

Plasma osteoprotegerin predicts adverse cardiovascular events in stable coronary artery disease: the PEACE trial

Background

Osteoprotegerin (OPG) is a secretory glycoprotein and participates in the progression of atherosclerotic lesions. We aim to explore the relationship between OPG and the prognosis of coronary artery disease (CAD).

Methods

Plasma OPG concentrations were measured in 3,766 patients with stable CAD enrolled in the PEACE trial. The PEACE trial (NCT00000558) group followed up the patients and examined their future clinical outcomes.

Results

In summary, 208 (5.5%) primary outcomes occurred, 295 patients (7.8%) died from all-cause death, 128 (3.4%) died from cardiovascular causes, and 94 (2.5%) experienced heart failure during a median follow-up of 1,892 days. In addition, we found that higher plasma levels of OPG were associated with a higher incidence of all-cause death, cardiovascular death, and heart failure, even after adjusting clinical cofounders.

Conclusion

It was demonstrated that elevated plasma OPG levels were associated with an increased incidence of all-cause death, cardiovascular death, and heart failure in patients with stable CAD.

Systematic Review Registration

https://clinicaltrials.gov/ct2/show/NCT00000558?term=NCT00000558&draw=2&rank=1, identifier: NCT00000558.

Tumor Necrosis Factor Family Members and Myocardial Ischemia-Reperfusion Injury: State of the Art and Therapeutic Implications

Ischemic heart disease is the principal cause of death worldwide and clinically manifests as myocardial infarction (MI), stable angina, and ischemic cardiomyopathy. Myocardial infarction is defined as an irreversible injury due to severe and prolonged myocardial ischemia inducing myocardial cell death. Revascularization is helpful in reducing loss of contractile myocardium and improving clinical outcome. Reperfusion rescues myocardium from cell death but also induces an additional injury called ischemia-reperfusion injury. Multiple mechanisms are involved in ischemia-reperfusion injury, such as oxidative stress, intracellular calcium overload, apoptosis, necroptosis, pyroptosis, and inflammation. Various members of the tumor necrosis factor family play a key role in myocardial ischemia-reperfusion injury. In this article, the role of TNFα, CD95L/CD95, TRAIL, and the RANK/RANKL/OPG axis in the regulation of myocardial tissue damage is reviewed together with their potential use as a therapeutic target.

Serum osteoprotegerin levels, endothelial function and carotid intima-media thickness in type 2 diabetic patients

OBJECTIVES

Osteoprotegerin (OPG), a well-known protein that inhibits osteoclast formation and activity, might also be a potential marker for identifying patients with high cardiovascular risk. This study aimed to compare OPG levels, FMD, and CIMT measurements in subjects with vs. without diabetes and investigate the association of serum osteoprotegerin level with the early atherosclerotic markers, endothelial function, and carotid intima-media thickness (CIMT) in patients with type 2 diabetes mellitus (DM2).

METHODS

Forty-nine patients with DM2 (F/M: 26/23, 49.3 ± 10.0 years) and 45 healthy volunteers (F/M: 26/19, 48.3 ± 7.5 years) were included in this cross-sectional study. Serum OPG levels were measured by solid-phase enzyme-linked immunosorbent assay (ELISA). Fasting plasma glucose (FPG) and HbA1c levels were measured. CIMT was measured by B-mode ultrasound, and endothelial function was evaluated via flow-mediated dilation (FMD) of the brachial artery with Doppler ultrasonography.

RESULTS

Serum OPG levels were significantly higher in patients with DM2 (617.0 ± 111.0 pg/mL) compared to controls (481.0 ± 96.0 pg/mL, p < 0.001). While CIMT in diabetic patients (0.65 + 0.13 mm) was higher than controls (0.54 ± 0.10 mm, p = 0.009), FMD measurement was lower in DM2 group (4.2% ± 3.1 mm vs. 7.6% ± 4.1 mm, p = 0.01). Univariate analysis showed that OPG was associated with the presence of diabetes (OR: 6.999, p = 0.001, R²: 15.1%) and hypertension (OR = 6.925, p = 0.001, R²: 13.2%). There was no relationship between OPG levels and CIMT or FMD.

CONCLUSION

Osteoprotegerin and CIMT levels were increased, and FMD measurements were decreased in patients with DM2. No association between CIMT, FMD, and OPG measurements was observed. The presence of DM and hypertension were associated with circulating OPG levels.

Novel multi-marker proteomics in phenotypically matched patients with ST-segment myocardial infarction: association with clinical outcomes

Early prediction of significant morbidity or mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) represents an unmet clinical need. In phenotypically matched population of 139 STEMI patients (72 cases, 67 controls) treated with primary percutaneous coronary intervention, we explored associations between a 24-h relative change from baseline in the concentration of 91 novel biomarkers and the composite outcome of death, heart failure, or shock within 90 days. Additionally, we used random forest models to predict the 90-day outcomes. After adjustment for false discovery rate, the 90-day composite was significantly associated with concentration changes in 14 biomarkers involved in various pathophysiologic processes including: myocardial fibrosis/remodeling (collagen alpha-1, cathepsin Z, metalloproteinase inhibitor 4, protein tyrosine phosphatase subunits), inflammation, angiogenesis and signaling (interleukin 1 and 2 subunits, growth differentiation factor 15, galectin 4, trefoil factor 3), bone/mineral metabolism (osteoprotegerin, matrix extracellular phosphoglycoprotein and tartrate-resistant acid phosphatase), thrombosis (tissue factor pathway inhibitor) and cholesterol metabolism (LDL-receptor). Random forest models suggested an independent association when inflammatory markers are included in models predicting the outcomes within 90 days. Substantial heterogeneity is apparent in the early proteomic responses among patients with acutely reperfused STEMI patients who develop death, heart failure or shock within 90 days. These findings suggest the need to consider synergistic multi-biomarker strategies for risk stratification and to inform future development of novel post-myocardial infarction therapies.

Osteoprotegerin and RANKL-RANK-OPG-TRAIL signalling axis in heart failure and other cardiovascular diseases

Osteoprotegerin (OPG) is a glycoprotein involved in the regulation of bone remodelling. OPG regulates osteoclast activity by blocking the interaction between the receptor activator of nuclear factor kappa B (RANK) and its ligand (RANKL). More and more studies confirm the relationship between OPG and cardiovascular diseases. Numerous studies have confirmed that a high plasma concentration of OPG and a low concentration of tumour necrosis factor–related apoptosis inducing ligand (TRAIL) together with a high OPG/TRAIL ratio are predictors of poor prognosis in patients with myocardial infarction. A high plasma OPG concentration and a high ratio of OPG/TRAIL in the acute myocardial infarction are a prognostic indicator of adverse left ventricular remodelling and of the development of heart failure. Ever more data indicates the participation of OPG in the regulation of the function of vascular endothelial cells and the initiation of the atherosclerotic process in the arteries. Additionally, it has been shown that TRAIL has a protective effect on blood vessels and exerts an anti-atherosclerotic effect. The mechanisms of action of both OPG and TRAIL within the cells of the vascular wall are complex and remain largely unclear. However, these mechanisms of action as well as their interaction in the local vascular environment are of great interest to researchers. This article presents the current state of knowledge on the mechanisms of action of OPG and TRAIL in the circulatory system and their role in cardiovascular diseases. Understanding these mechanisms may allow their use as a therapeutic target in cardiovascular diseases in the future.

The relevance of microRNA in post-infarction left ventricular remodelling and heart failure

Myocardial infarction and post-infarction left ventricular remodelling involve a high risk of morbidity and mortality. For this reason, ongoing research is being conducted in order to learn the mechanisms of unfavourable left ventricular remodelling following a myocardial infarction. New biomarkers are also being sought that would allow for early identification of patients with a high risk of post-infarction remodelling and dysfunction of the left ventricle. In recent years, there has been ever more experimental data that confirms the significance of microRNA in cardiovascular diseases. It has been confirmed that microRNAs are stable in systemic circulation, and can be directly measured in patients’ blood. It has been found that significant changes occur in the concentrations of various types of microRNA in myocardial infarction and heart failure patients. Various types of microRNA are also currently being intensively researched in terms of their usefulness as markers of cardiomyocyte necrosis, and predictors of the post-infarction heart failure development. This paper is a summary of the current knowledge on the significance of microRNA in post-infarction left ventricular remodelling and heart failure.

The Emerging Role of Bone Markers in Diagnosis and Risk Stratification of Patients With Coronary Artery Disease

Molecules that govern bone metabolism, such as osteoprotegerin (OPG) and osteopontin (OPN), have been isolated from other tissues, including blood vessels. Atherosclerosis and coronary artery disease (CAD) are leading causes of mortality worldwide. Despite novel biochemical and imaging techniques, early detection of CAD is still unsatisfactory. Experimental data indicate that bone turnover markers (BTMs) contribute to the development of atherosclerosis. This finding has sparked interest in their clinical use. This narrative review analyzed information from >50 human studies, which strongly suggest that OPG, OPN, and alkaline phosphatase (ALP) serum concentrations are altered in patients with CAD. Osteoprotegerin seems to be more useful for the detection of early disease, while OPN and ALP are recruited in vessels after the establishment of disease. Osteocalcin may be used as a flow cytometry marker for endothelial progenitor cells and can constitute a marker to monitor response to interventional treatments and risk of restenosis. However, most data derive from observational studies. Incorporation of BTMs in multifactorial computational algorithms could further determine their role in CAD diagnosis and prognosis together with other imaging techniques and biochemical markers.

Osteoprotegerin and Cardiovascular Events in High-Risk Populations: Meta-Analysis of 19 Prospective Studies Involving 27 450 Participants

Background Osteoprotegerin is a cytokine involved in bone metabolism as well as vascular calcification and atherogenesis. Although circulating osteoprotegerin levels are robustly associated with incident cardiovascular disease ( CVD ) in the general population, its relevance as a biomarker among populations at high CVD risk is less clear. Methods and Results Three independent reviewers systematically searched PubMed, EMBASE , and Web of Science to identify prospective studies that had recruited participants on the basis of having conditions related to high CVD risk. A total of 19 studies were eligible for inclusion, reporting on 27 450 patients with diabetes mellitus (2 studies), kidney disease (7 studies), preexisting heart disease (5 studies), or recent acute coronary syndromes (5 studies) at baseline. Over a mean follow-up of 4.2 years, 4066 CVD events were recorded. In a random-effects meta-analysis, the pooled risk ratio for CVD events comparing people in the top versus the bottom tertile of osteoprotegerin concentration was 1.30 (95% confidence interval, 1.12-1.50; P<0.001; I2=68.3%). There was evidence for presence of publication bias ( P value from Egger's test=0.013). Correction for publication bias using the trim-and-fill method reduced the risk ratio to 1.21 (95% confidence interval, 1.03-1.42; P<0.001). The risk ratios did not vary significantly by population type, geographical region, statistical adjustment, sample or assay type, age, sex, or length of follow-up. Conclusions In populations at high CVD risk, elevated circulating osteoprotegerin levels are associated with a higher risk for future CVD events. The magnitude of association appears weaker than in the general population.

The Role of Osteoprotegerin as a Cardioprotective Versus Reactive Inflammatory Marker: the Chicken or the Egg Paradox

Cardiovascular disease is one of the most frequent causes of mortality and morbidity worldwide. Several variables have been identified as risk factors for cardiovascular disease. Recently, the role of receptor activator of nuclear factor kappa B, receptor activator of nuclear factor kappa B ligand, and the osteoprotegerin system has been recognized as more important in the pathogenesis of cardiovascular disease. Besides their roles in the regulation of bone resorption, these molecules have been reported to be associated with the pathophysiology of cardiovascular disease. There are conflicting data regarding the impact of osteoprotegerin, a glycoprotein with a regulatory role in the cardiovascular system. The aim of this review is to discuss the current knowledge and the role of osteoprotegerin in cardiovascular disease.

Osteoprotegerin Is Associated With Major Bleeding But Not With Cardiovascular Outcomes in Patients With Acute Coronary Syndromes: Insights From the PLATO (Platelet Inhibition and Patient Outcomes) Trial

Background

Elevated levels of osteoprotegerin, a secreted tumor necrosis factor–related molecule, might be associated with adverse outcomes in patients with coronary artery disease. We measured plasma osteoprotegerin concentrations on hospital admission, at discharge, and at 1 and 6 months after discharge in a predefined subset (n=5135) of patients with acute coronary syndromes in the PLATO (Platelet Inhibition and Patient Outcomes) trial.

Methods and Results

The associations between osteoprotegerin and the composite end point of cardiovascular death, nonprocedural spontaneous myocardial infarction or stroke, and non–coronary artery bypass grafting major bleeding during 1 year of follow‐up were assessed by Cox proportional hazards models. Event rates of the composite end point per increasing quartile groups at baseline were 5.2%, 7.5%, 9.2%, and 11.9%. A 50% increase in osteoprotegerin level was associated with a hazard ratio (HR) of 1.31 (95% confidence interval [CI], 1.21–1.42) for the composite end point but was not significant in adjusted analysis (ie, clinical characteristics and levels of C‐reactive protein, troponin T, NT‐proBNP [N‐terminal pro‐B‐type natriuretic peptide], and growth differentiation factor‐15). The corresponding rates of non–coronary artery bypass grafting major bleeding were 2.4%, 2.2%, 3.8%, and 7.2%, with an unadjusted HR of 1.52 (95% CI, 1.36–1.69), and a fully adjusted HR of 1.26 (95% CI, 1.09–1.46). The multivariable association between the osteoprotegerin concentrations and the primary end point after 1 month resulted in an HR of 1.09 (95% CI, 0.89–1.33); for major bleeding after 1 month, the HR was 1.33 (95% CI, 0.91–1.96).

Conclusions

In patients with acute coronary syndrome treated with dual antiplatelet therapy, osteoprotegerin was an independent marker of major bleeding but not of ischemic cardiovascular events. Thus, high osteoprotegerin levels may be useful in increasing awareness of increased bleeding risk in patients with acute coronary syndrome receiving antithrombotic therapy.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00391872.

Relationship between osteoprotegerin and mortality in decompensated heart failure with preserved ejection fraction

AIM

The aim of this study was to evaluate whether osteoprotegerin - an emerging inflammatory biomarker in cardiovascular diseases - predicts outcomes in patients with acute heart failure and preserved ejection fraction.

METHODS

We measured urea, creatinine, hemoglobin, high-sensitivity C-reactive protein, N-terminal pro-B-type natriuretic peptide and osteoprotegerin on admission in 177 patients admitted with decompensated heart failure and left ventricular ejection fraction at least 45%. The population was divided according to the median values of osteoprotegerin (158.6 ng/l). Primary and secondary endpoints were all-cause mortality and death/readmission at 1-year follow-up, respectively. Multivariable Cox models were generated for osteoprotegerin and common risk factors. We also evaluated the reclassification of patients into risk categories after adding this biomarker to the model.

RESULTS

A total of 43 patients died during the follow-up and 84 had a combined event. Kaplan-Meier curves showed significantly increased primary and secondary endpoints according to the median of osteoprotegerin (log-rank, P < 0.0001 and 0.001, respectively). After adjustment for age, estimated glomerular filtration rate, hemoglobin, N-terminal pro-B-type natriuretic peptide, BMI and New York Heart Association III-IV, osteoprotegerin was a significant predictor of primary endpoint evaluated as continuous and categorized variable (relative risk 2.49, 95% confidence interval 1.18-5.24, P = 0.016 and relative risk 2.35, 95% confidence interval 1.11-4.96, P = 0.025, respectively). The clinical prediction model with osteoprotegerin evaluated with Net Reclassification Index was not significant.

CONCLUSION

Osteoprotegerin is independently associated with all-cause mortality in patients hospitalized for heart failure with preserved ejection fraction. However, adding this biomarker into a risk model does not improve its prediction value.

Osteoprotegerin is a significant prognostic factor for overall survival in patients with primary systemic amyloidosis independent of the Mayo staging

Bone metabolism has not been systematically studied in primary (AL) amyloidosis. Thus we prospectively evaluated bone remodeling indices in 102 patients with newly diagnosed AL amyloidosis, 35 healthy controls, 35 newly diagnosed myeloma and 40 monoclonal gammopathy of undetermined significance patients. Bone resorption markers (C-telopeptide of type-1 collagen, N-telopeptide of type-1 collagen) and osteoclast regulators (soluble receptor activator of nuclear factor-κB ligand (sRANKL), osteoprotegerin (OPG)) were increased in AL patients compared with controls (P<0.01), but bone formation was unaffected. Myeloma patients had increased bone resorption and decreased bone formation compared with AL patients, while sRANKL/OPG ratio was markedly decreased in AL, due to elevated OPG in AL (P<0.001). OPG correlated with N-terminal pro-brain natriuretic peptide (P<0.001) and was higher in patients with cardiac involvement (P=0.028) and advanced Mayo stage (P=0.001). OPG levels above the upper value of healthy controls was associated with shorter survival (34 versus 91 months; P=0.026), while AL patients with OPG levels in the top quartile had very short survival (12 versus 58 months; P=0.024). In Mayo stage 1 disease, OPG identified patients with poor survival (12 versus >60 months; P=0.012). We conclude that increased OPG in AL is not only a compensation to osteoclast activation but may also reflect early cardiac damage and may identify patients at increased risk of death within those with earlier Mayo stage.

ST elevation myocardial infarction: recent advances and updates

ST elevation myocardial infarction (STEMI) remains a leading cause of morbidity, mortality and disability worldwide. Statistically, a trend towards improvements in morbidity and mortality has been consistent over the years, which is attributed primarily to the modification of risk factors, healthier lifestyles, treatment advances and better management of door-to-balloon times via STEMI systems. However, a major challenge in the coming years will be the baby boomers (born between the years 1946 and 1964) coming into old age. The first baby boomers turned 65 in year 2011. As the baby boomers age in the coming years, the incidence of coronary heart disease is likely to increase, and so there will be a greater need to have major advances in the management of coronary heart disease in order to deal with this additional incidence. The scope of this article is to review recent advances in the management of STEMI and to provide an updated overview.

High osteoprotegerin levels predict MACCE in STEMI patients, but are not associated with myocardial salvage

OBJECTIVES

High circulating levels of osteoprotegerin (OPG) carry prognostic impact in cohorts with various cardiovascular diagnoses. With the present study, we aim to investigate the role of OPG within the scale of myocardial damage.

DESIGN

This study includes 219 consecutive patients with acute ST-elevation myocardial infarction randomized to primary percutaneous coronary intervention (pPCI) or pPCI and remote ischemic per-conditioning. Salvage index via myocardial single-photon emission CT assessment (data available in 61% of the patients) was performed, and derived from Day 1 (myocardial area at risk) and Day 30 (final infarct size). Plasma OPG levels were measured using an in-house immunoassay. A combined end-point of all-mortality, myocardial infarction, stroke, readmission for heart failure and ischemic stroke/transient ischemic attack (Major Adverse Cardiac and Cerebrovascular Events [MACCE]) was used for follow-up; 45 (38-48 months).

RESULTS

High OPG levels were associated with the severity of cardiovascular disease. During follow-up, OPG was a predictor of MACCE (unadjusted, HR: 2.1, 95% CI: 1.14-3.85, P = 0.017). Adjustments for age, gender, and body mass index preserved the independent predictive power of OPG. However, OPG levels were neither associated with salvage index nor with the final infarct size. Remote ischemic per-conditioning had no effect on OPG levels.

CONCLUSION

Despite absent association between OPG levels and the scale of myocardial damage, high OPG levels predict a significantly increased risk of MACCE.

Osteoprotegerin: a new biomarker for impaired bone metabolism in complex regional pain syndrome?

Osteoprotegerin (OPG) is important for bone remodeling and may contribute to complex regional pain syndrome (CRPS) pathophysiology. We aimed to assess the value of OPG as a biomarker for CRPS and a possible correlation with radiotracer uptake in 3-phase bone scintigraphy (TPBS). OPG levels were analyzed in 23 CRPS patients (17 women; mean age 50±9.0 years; disease duration: 12 weeks [IQR 8-24]), 10 controls (6 women; mean age 58±9.6 years) and 21 patients after uncomplicated fractures (12 women; mean age: 43±15 years; time after fracture: 15 weeks [IQR: 6-22]). The CRPS and control patients also underwent TPBS. OPG in CRPS patients was significantly increased by comparison with both control groups (P=0.001; Kruskal-Wallis test; CRPS patients: 74.1 pg/mL [IQR: 47.1-100.7]; controls: 46.7 pg/mL [IQR: 35.5-55.0]; P=0.004; fracture patients: 45.9 pg/mL [IQR: 37.5-56.7]; P=0.001). As a diagnostic test for CRPS, OPG had a sensitivity of 0.74, specificity of 0.80, positive predictive value of 68% and negative predictive value of 84%. Receiver operating characteristic curve analysis showed an area under the curve of 0.80 (CI: 0.68-0.91). For the CRPS-affected hand, a significant correlation between OPG and TPBS region of interest analysis in phase III was detected (carpal bones; r=0.391; P=0.03). The persistent OPG increase in CRPS indicates enhanced osteoblastic activity shown by increased radiotracer uptake in TPBS phase III. A contribution of bone turnover to CRPS pathophysiology is likely. OPG might be useful as a biomarker for CRPS.

Risk assessment of post-infarction heart failure. Systematic review on the role of emerging biomarkers

The prognostic significance of cardiospecific troponins and natriuretic peptides in patients with myocardial ischemia is well established, and their measurement is now endorsed by the most important guidelines and recommendations for diagnosis and management of heart failure (HF). Additional biomarkers have also been investigated to support clinical judgment and diagnostic imaging in the stratification of risk of cardiac dysfunction in patients with myocardial infarction (MI). We have performed a systematic analysis of the current scientific literature regarding the most important biomarkers of HF, selecting all prospective studies with adequate sample size (i.e. >100 patients) that have assessed, during the early phase of myocardial ischemia, the prognostic value of emergent biomarkers for new-onset HF or deterioration of cardiac function in patients with MI. This analysis has provided some good evidence suggesting that, in most cases, the use of diagnostic biomarkers of cardiac dysfunction does not translate into efficient risk prediction of HF. However, some notable exceptions were found, including biomarkers of cardiac fibrosis (especially galectin-3), growth differentiation factor-15 (GDF-15), osteoprotegerin, C-reactive protein (CRP), and red blood cell distribution width (RDW). Nevertheless, future studies with well-defined characteristics including the use of larger sample sizes, standardized end points, and replication populations, along with benchmark analyses against other consolidated biomarkers (i.e. cardiospecific troponins and natriuretic peptides), should be planned. Such evaluations will help to establish whether an integrated approach including biomarkers of different pathogenetic pathways - for example, apoptosis, stress of cardiomyocytes, cardiac fibrosis, inflammation, and extra-cardiac involvement - may be cost effective for identifying patients at increased risk of developing HF, and who, therefore, may benefit from a tailored therapeutic strategy.

Osteoprotegerin (OPG) as a biomarker for diabetic cardiovascular complications

Osteoprotegerin (OPG) is a glycoprotein involved in bone metabolisms and with a regulatory role in immune, skeletal and vascular systems. Recently, circulating OPG levels have emerged as independent biomarkers of cardiovascular disease (CVD) in patients with acute or chronic heart disease, as well as in the healthy population. Furthermore, OPG has been implicated in various inflammations and linked to diabetes and poor glycaemic control. This review focuses on the relations between circulating OPG levels and cardiovascular complications, with special emphasis on diabetic patients. OPG levels were observed to increase concurrently with the severity of diabetic complications, that is, with the highest circulating OPG levels observed in diabetic patients dying from CVD. Although the clinical prognostic use of OPG may seem far away, OPG does look promising as a biomarker in order to help the cardiologist to a better risk-stratification of the patients.

Association of serum osteoprotegerin with vascular calcification in patients with type 2 diabetes

Background

Osteoprotegerin is a member of the tumor necrosis factor-related family and inhibits RANK stimulation of osteoclast formation as a soluble decoy receptor. The goal of this study was to determine the relationship of serum osteoprotegerin with vascular calcification in patients with type 2 diabetes.

Methods

The subjects were 124 patients with type 2 diabetes mellitus, including 88 males and 36 females with a mean (± SD) age of 65.6 ± 8.2 years old. Serum levels of osteoprotegerin, osteocalcin, fibroblast growth factor 23 (FGF23), 25-hydroxyvitamin D3 and adiponectin were measured by ELISA. Vascular calcification in the cervical artery was examined by ultrasound sonography. The subjects were divided into 4 quartiles depending on serum osteoprotegerin levels.

Results

Vascular calcification was significantly higher in the 4th quartile and significantly lower in the 1st quartile of serum osteoprotegerin levels, compared to other quartiles. There were no differences in serum osteoprotegerin and vascular calcification among patients with different stages of diabetic nephropathy, but serum FGF23 levels were elevated in those with stage 4 diabetic nephropathy. Simple regression analysis showed that serum osteoprotegerin levels had significant positive correlations with age, systolic blood pressure and serum adiponectin levels, and significant negative correlations with BMI and serum 25-hydroxyvitamin D3.

Conclusions

These findings suggest that elevated serum osteoprotegerin may be involved in vascular calcification independently of progression of diabetic nephropathy in patients with type 2 diabetes.