Estimation of serum neopterin in patients with acute coronary syndrome

Evaluation of neopterin levels and kynurenine pathway in patients with acute coronary syndrome

BACKGROUND

Coronary atherosclerosis is the leading cause of coronary artery disease. Several investigations have indicated that tear-sensitive plaques contain macrophages and T cells. Neopterin is an essential cellular immune response biomarker. The main goal of this study was to see if there were any changes in biomarkers like unconjugated pteridines, neopterin, and biopterin, as well as kynurenine pathway enzymes like indoleamine 2,3-dioxygenase (IDO), which catalyzes the rate-limiting step in tryptophan degradation, in patients with the acute coronary syndrome (ACS) caused by angiographic atherosclerosis.

METHODS

High-performance liquid chromatography was used to determine the amounts of neopterin, biopterin, and creatinine in urine samples, as well as tryptophan and kynurenine in serum samples. The enzyme-linked immunosorbent assay was used to assess the amounts of neopterin in serum samples. The measured parameters were evaluated between ACS patients and controls.

RESULTS

The measured levels of neopterin, biopterin and the kynurenine to tryptophan ratio reflecting IDO activity, and the specifically known biomarkers such as cardiac troponin, creatine kinase, myoglobin, and natriuretic peptides are statistically higher in ACS patients compared to control subjects. On the other hand, the measured parameters are inadequate to classify the conventional kinds of ACS, ST-elevation- and non-ST-elevation- myocardial infarction.

CONCLUSIONS

The study found that determining and using neopterin and IDO parameters as biomarkers in individuals with the ACS can support traditional biomarkers. However, it can be concluded that evaluating pteridine biomarkers solely have no privilege to clinical findings in ACS diagnosis and classification.

Pro-inflammatory Cytokines in Acute Coronary Syndromes

BACKGROUND

Over the last decades, the role of inflammation and immune system activation in the initiation and progression of coronary artery disease (CAD) has been established.

OBJECTIVES

The study aimed to present the interplay between cytokines and their actions preceding and shortly after ACS.

METHODS

We searched in a systemic manner the most relevant articles to the topic of inflammation, cytokines, vulnerable plaque and myocardial infarction in MEDLINE, COCHRANE and EMBASE databases.

RESULTS

Different classes of cytokines (intereleukin [IL]-1 family, Tumor necrosis factor-alpha (TNF-α) family, chemokines, adipokines, interferons) are implicated in the entire process leading to destabilization of the atherosclerotic plaque, and consequently, to the incidence of myocardial infarction. Especially IL-1 and TNF-α family are involved in inflammatory cell accumulation, vulnerable plaque formation, platelet aggregation, cardiomyocyte apoptosis and adverse remodeling following the myocardial infarction. Several cytokines such as IL-6, adiponectin, interferon-γ, appear with significant prognostic value in ACS patients. Thus, research interest focuses on the modulation of inflammation in ACS to improve clinical outcomes.

CONCLUSION

Understanding the unique characteristics that accompany each cytokine-cytokine receptor interaction could illuminate the signaling pathways involved in plaque destabilization and indicate future treatment strategies to improve cardiovascular prognosis in ACS patients.

Elevated serum neopterin and homocysteine increased the risk of ischemic stroke in patients with transient ischemic attack

Objective: To investigate the correlation between serum neopterin, homocysteine (Hcy) and the risk of developing ischemic stroke (IS) in patients with transient ischemic attack (TIA).

Methods: Ninety-two TIA patients were prospectively recruited at the First Affiliated Hospital of the Medical College, Shihezi University, Xinjiang Autonomous Region China. Of the included patients, 27 developed ischemic stroke (IS group) and other 65 cases did not (TIA group). Peripheral venous blood was obtained within 24 hours of TIA diagnosis. Serum neopterin, Hcy and serum lipid levels were tested and compared between IS and TIA groups.

Results: Serum neopterin (6.38±1.76 ng/mL vs 5.39±1.51 ng/mL), Hcy (17.95±4.10 μmol/L vs 15.30±3.66 μmol/L), TG (1.82±0.92 mmol/L vs 1.40±0.71 mmol/L) and LDL (3.31±0.67 mmol/L vs 2.69±0.62 mmol/L) of IS group were significantly higher than those of TIA group (p<0.05). The AUC of serum neopterin, Hcy, TG and LDL for predicting the risk of developing IS in patients with TIA were 0.68 (95%CI: 0.55-0.81, 0.68 (95%CI: 0.57-0.80), 0.64 (95%CI: 0.51-0.78) and 0.75 (95%CI: 0.63-0.86), respectively.

Conclusion: Serum neopterin, Hcy, TG and LDL are promising serological markers for predicting the increased risk of developing IS for patients with TIA.

Plasma levels of soluble VEGF receptor isoforms, circulating pterins and VEGF system SNPs as prognostic biomarkers in patients with acute coronary syndromes

Background

Development of collateral circulation in coronary artery disease is cardio-protective. A key process in forming new blood vessels is attraction to occluded arteries of monocytes with their subsequent activation as macrophages. In patients from a prospectively recruited post-acute coronary syndromes cohort we investigated the prognostic performance of three products of activated macrophages, soluble vascular endothelial growth factor (VEGF) receptors (sFlt-1 and sKDR) and pterins, alongside genetic variants in VEGF receptor genes, VEGFR-1 and VEGFR-2.

Methods

Baseline levels of sFlt-1 (VEGFR1), sKDR (VEGFR2) and pterins were measured in plasma samples from subgroups (n = 513; 211; 144, respectively) of the Coronary Disease Cohort Study (CDCS, n = 2067). DNA samples from the cohort were genotyped for polymorphisms from the VEGFR-1 gene SNPs (rs748252 n = 2027, rs9513070 n = 2048) and VEGFR-2 gene SNPs (rs2071559 n = 2050, rs2305948 n = 2066, rs1870377 n = 2042).

Results

At baseline, levels of sFlt-1 were significantly correlated with age, alcohol consumption, NTproBNP, BNP and other covariates relevant to cardiovascular pathophysiology. Total neopterin levels were associated with alcohol consumption at baseline. 7,8 dihydroneopterin was associated with BMI. The A allele of VEGFR-2 variant rs1870377 was associated with higher plasma sFlt-1 and lower levels of sKDR at baseline. Baseline plasma sFlt-1 was univariately associated with all cause mortality with (p < 0.001) and in a Cox’s proportional hazards regression model sFlt-1 and pterins were both associated with mortality independent of established predictors (p < 0.027).

Conclusions

sFlt-1 and pterins may have potential as prognostic biomarkers in acute coronary syndromes patients. Genetic markers from VEGF system genes warrant further investigation as markers of levels of VEGF system components in these patients.

Trial registration

Australian New Zealand Clinical Trials Registry. ACTRN12605000431628. 16 September 2005, Retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0894-1) contains supplementary material, which is available to authorized users.