Defining a role for novel biomarkers in acute coronary syndromes

Mechanism of Physical Exercise on Lowering Levels of C-Reactive Protein (CRP) in Overweight and Obese

Cases of overweight and obesity in the world increased continuously. In 2016, obesity increased by 3% in men and 6% in women compared to 1975. Overweight cases also increased by 20% in men and 23% in women compared to 1975. Overweight and obesity have been linked to an increase in adipose tissue in the body. Increased adipose tissue associated with inflammation, which one of its characteristics is an increase levels of C - Reactive Protein (CRP). This article aim is to describe the mechanism of physical exercise to diminish CRP level in overweight and obesity. Adipose tissue produces and releases various pro-inflammatory and anti-inflammatory factors such as leptin, adiponectin, resistin, TNF-α, IL-6, MCP-1 and CRP. One of the prevention and treatment of inflammatory for overweight and obesity cases is to do physical exercise. In cases of overweight and obesity, the physical exercise aims to increase energy expenditure. Physical exercise decreases the volume and amount of adipose and pre-adipose tissue as well as the number of endothelial cells and macrophages in adipose that contain pro-inflammation such as IL-1, TNF-α, CRP, serum amyloid protein (SAA), and cytokines. Physical exercise rises anti-inflammatory properties such as IL-10, IL-1ra which play a role in inhibiting the transduction of IL-1β signals and inhibiting TNF-α synthesis. Physical exercise also amplifies antioxidant enzymes such as SOD and GPX. The antioxidants play a role in fighting free radicals to reduce inflammation.

Biomarkers in heart failure: the past, current and future

Despite the enhanced knowledge of the pathophysiology of heart failure (HF), it still remains a serious syndrome with substantial morbidity, mortality, and frequent hospitalizations. These are due to the current improvements in other cardiovascular diseases (like myocardial infarction), the aging population, and growing prevalence of comorbidities. Biomarker-guided management has brought a new dimension in prognostication, diagnosis, and therapy options. Following the recommendation of natriuretic peptides (B-type natriuretic peptide and N-terminal-proBNP), many other biomarkers have been thoroughly studied to reflect different pathophysiological processes (such as fibrosis, inflammation, myocardial injury, and remodeling) in HF and some of them (like cardiac troponins, soluble suppression of tumorigenesis-2, and galectin 3) have subsequently been recommended to aid in the diagnosis and prognostication in HF. Consequently, multi-marker approach has also been approved owing to the varied nature of HF syndrome. In this review, we discussed the guidelines available for HF biomarkers, procedures for evaluating novel markers, and the utilities of both emerging and established biomarkers for risk stratification, diagnosis, and management of HF in the clinics. We later looked at how the rapidly emerging field-OMICs, can help transform HF biomarkers discoveries and establishment.

Cardiac biomarkers in heart failure

BACKGROUND

Heart failure is a syndrome characterized by the inability of the heart to meet the body's circulatory demands. Heart failure is a growing health issue worldwide and the prevalence of heart failure is expected to rise as populations age. Therapies and interventions for a variety of cardiac conditions continue to advance and biomarkers will play an increasing role in patient management.

METHODS

This is a review of the clinical research in blood based biomarkers for diagnosis, prognosis and therapeutic guidance of heart failure. The focus of this review is biomarkers that are currently available for clinical measurement, and their current and potential for applications for managing heart failure patients.

RESULTS

The various biologic pathways and physiologic processes of heart failure biomarkers represent a host of different including inflammation, remodeling, strain, neurohormonal activation, metabolism and cardiac myocyte injury. The clinical characteristics and applications of each heart failure biomarker are discussed.

CONCLUSION

As populations age and effective treatments and interventions for coronary artery disease improve, heart failure will increase in incidence and prevalence. Blood biomarkers will play an increasing role in the early diagnosis, therapeutic monitoring and management of heart failure patients in the future.

Clinical implications of elevated serum soluble CD137 levels in patients with acute coronary syndrome

OBJECTIVES

Atherosclerosis is a chronic inflammatory disease. Research has focused on identifying specific serum biomarkers to detect vulnerable plaques. These markers serve as diagnostic tools for acute coronary syndrome and assist in identifying high-risk patients. However, the existing data are limited and conflicting. This study tested the hypothesis that CD137 levels identify patients with acute coronary syndrome who are at a heightened risk for recurrent cardiac events.

METHODS

The levels of soluble CD137 (sCD137) were measured using ELISA in 180 patients with acute coronary syndrome and 120 patients with acute chest pain. Platelet activation was assessed by flow cytometry. Receiver operating characteristic curve analysis was performed to evaluate the prognostic characteristics of sCD137.

RESULTS

The levels of sCD137 were elevated in 75 patients with acute coronary syndromes and 20 patients with acute chest pain (>35.0 ng/ml). In patients with acute coronary syndrome, elevated sCD137 levels (>35.0 ng/ml) indicated an increased risk for major adverse cardiovascular events (OR =1.93, 95% CI: 1.39-2.54). Elevated serum levels of sCD137 and cTnT were correlated with a significantly increased risk of major adverse cardiovascular events in both groups after 30 days, six months and nine months of follow-up. The increased sCD137 levels were significantly correlated with the levels of troponin I (r = 0.4799, p<0.001). Importantly, 26 patients with normal cTnI levels had acute coronary syndrome. However, elevated sCD137 levels identified these patients as a being high-risk subgroup (OR = 2.14, 95% CI: 1.25-4.13).

CONCLUSIONS

Elevated sCD137 levels indicate an increased risk of cardiovascular events in patients with acute coronary syndrome. Soluble CD137 may be a useful prognostic marker or indicator for adverse events in patients with acute coronary syndrome.

Von Willebrand factor and oxidative stress parameters in acute coronary syndromes

Considering the role of von Willebrand factor (vWf) in hemostasis, and the role of oxidative stress in the development of endothelial dysfunction and atherosclerotic disease, the aim of our study was to investigate the relationship between vWf, parameters of oxidative stress and different types of acute coronary syndromes (ACS). Levels of vWf activity (vWfAct), vWf antigen (vWfAg), nitric oxide (estimated through nitrites–NO₂  ⁻), superoxide anion radical (O₂  ⁻), hydrogen peroxide (H₂O₂), index of lipid peroxidation (estimated through thiobarbituric acid reactive substances–TBARS), superoxide dismutase (SOD) and catalase (CAT) activity of 115 patients were compared with those of 40 healthy controls. ACS patients had significantly higher vWfAct and vWfAg levels, as well as TBARS levels, while their levels of NO₂  ⁻, H₂O₂, SOD and CAT activities were lower than controls'. vWfAg showed high specificity and sensitivity as a test to reveal healthy or diseased subjects. Multivariant logistic regression marked only vWfAg and TBARS as parameters that were under independent effect of ACS type. The results of our study support the implementation of vWf in clinical rutine and into therapeutic targets, and suggest that ACS patients are in need of antioxidant supplementation to improve their impaired antioxidant defence.

Evaluation of serum soluble OX40 ligand as a prognostic indicator in acute coronary syndrome patients

BACKGROUND

Long-term risk stratification in patients presented with acute coronary syndromes (ACS) is possible by measuring cardiac troponin (cTn). The present study evaluates the clinical predictive value of increased serum soluble OX40 ligand (sOX40L) in patients with ACS and acute chest pain.

METHODS

The levels of serum soluble OX40L were measured by ELISA in patients with ACS (168) and acute chest pain (106). The platelet activation was assessed by flow cytometry.

RESULTS

The levels of serum soluble OX40L were increased (> 40.0 ng/ml) in 56 patients with ACS (33.3%) and in 17 patients with acute chest pain (> 40.0 ng/ml), respectively. The increased sOX40L level was significantly correlated with measured levels of troponin I (r = 0.47, p < 0.001) and the increased soluble OX40L levels (> 40.0 ng/ml) were associated with higher risk for acute myocardial infarction (AMI), sudden death and recurrent angina. Both increased serum levels of sOX40L and cTnT showed a significantly increased risk of major adverse cardiovascular events (including AMI, sudden death and recurrent angina) in two groups during 30 days, 6 months and 9 months of follow-up.

CONCLUSION

In patients with ACS, elevation of baseline sOX40L levels indicates an increased risk for cardiovascular events. Serum soluble OX40L might be a useful prognostic marker or indicator for adverse events in patients with ACS.

Identification of myocardial injury in the emergency setting

Within the past decade, the use of biomarkers to detect myocardial injury in the emergency department (ED) has been given increasing prominence as evident by the numerous studies and guidelines documenting their use. This review details the scope of the clinical problem, the history of changes in the definition of myocardial infarction (MI) and the new approaches, as well as suggestions for using laboratory biomarkers in the early detection of MI in the ED.

Current Trends in Diagnostic Biomarkers of Acute Coronary Syndrome

The diagnosis and management of patients with acute coronary syndrome (ACS) have evolved dramatically over the past decade. Biomarkers play an important role in the diagnosis of ACS, especially in unstable angina and non-ST-segment elevation myocardial infarction. Among these, cardiac troponin and creatine kinase appear to be the most sensitive and specific markers of myocardial injury. Recent studies have revealed several novel biomarkers. Elevated levels of C-reactive protein and interleukin-6 are strong independent markers of increased mortality among patients with ACS. However, the ideal biomarkers that offer early detection, risk stratification, selection of therapy, monitoring disease progression, and treatment efficacy remain to be elucidated. This review assesses limitations and contemporary needs for biomarkers in the context of diagnosis of ACS. It also discusses the newly developing technologies for novel biomarkers or novel biomarker protein signatures discovery, and importance of point-of-care testing for future management. Key words: Cardiac troponin, Creatine kinase, NSTEMI

PAPP-A as a marker of increased long-term risk in patients with chest pain

OBJECTIVES

Long-term risk stratification in patients presenting with acute coronary syndromes (ACS) is possible by measuring cardiac troponin (cTn). The present study examined whether PAPP-A measured in an emergency department (ED) chest pain population in association with conventional and novel high sensitivity cTn (hs-cTnI) assays can predict long-term mortality.

METHODS

In 320 patients with cTn measurements the earliest heparinized plasma PAPP-A concentration after presentation was used for risk stratification for death by Kaplan-Meier and Cox analyses. Subgroup analyses using the earliest PAPP-A concentrations were also performed in a cohort of subjects with presentation cTnI < or = 99th percentile but with significantly changing cardiac troponin concentrations as measured by the AccuTnI assay and the hs-cTnI assay (n=45 and 120 subjects, respectively).

RESULTS

Subjects with PAPP-A concentrations in the highest tertile were at higher risk for death (HR > 2.00; p < or = 0.05 at 2 years) even after adjusting for cTnI at presentation. In the cohort with cTnI < or = 99th percentile but with changing hs-cTnI concentrations, subjects in the top PAPP-A tertile had a higher probability for death (p=0.02).

CONCLUSION

Early measurement of PAPP-A may identify chest pain patients at higher risk for long-term death. Additional prospective ACS studies are required to fully elucidate PAPP-A's role.