Prognostic value of neopterin levels in treated patients with hypertension and chest pain but without obstructive coronary artery disease

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.

Role of neopterin as an inflammatory biomarker in congestive heart failure with insights on effect of drug therapies on its level

Inflammation has a major role in the pathogenesis of heart failure (HF). It triggers a cascade that leads to the release of pro-inflammatory cytokines which in turn cause cardiac hypertrophy, fibrosis, apoptosis, negative inotorpy and leukocyte recruitment which worsen the condition. Neopterin is an inflammatory biomarker which is released as a response to macrophage activation. Levels of neopterin are elevated in conditions which has an immunological component such as autoimmune disease, viral and bacterial infections and malignancy. Neopterin levels were found to be elevated in patients with HF. This is due to the fact that inflammation takes place during the development of the condition. Studies demonstrated that neopterin can be used as a biomarker for diagnosing HF, determining severity of the disease and monitoring its progression. Neopterin levels were higher in patients with New York Heart Association classification (NYHA) III–IV more than class I–II. Moreover, neopterin levels correlated well with morbidity and mortality. It has been suggested that neopterin be monitored levels to determine effectiveness of HF treatment options.

The impact of antihypertensive pharmacotherapy on interplay between protein-bound uremic toxin (indoxyl sulfate) and markers of inflammation in patients with chronic kidney disease

PURPOSE

Indoxyl sulfate (IS) is one of the most potent uremic toxins involved in chronic kidney disease (CKD) progression, induction of inflammation, oxidative stress, and cardiovascular diseases occurrence. It is proved that hypertension is a common CVD complication and a major death risk factor as well as contributes for decline in a renal function. The aim of our study was to investigate how implementing of antihypertensive therapy impact IS concentrations and the associations between IS and markers of renal function, inflammation and oxidative stress.

METHODS

Study was conducted on 50 patients diagnosed with CKD and hypertension, divided into three groups: without hypotensive therapy (CKD-NONE), hypotensive monotherapy (CKD-MONO), and hypotensive polypharmacotherapy (CKD-POLI), and 18 healthy volunteers. The markers of inflammation [interleukin-6, tumor necrosis factor-alpha (TNF-α), high-sensitive C-reactive protein (hs-CRP), neopterin, ferritin], oxidative status [superoxide dismutase (Cu/Zn-SOD), antibodies against oxidized low-density lipoprotein (oxLDL-abs)], and selectins were determinate using immunoenzymatic methods. IS levels were assayed using high-performance liquid chromatography and other parameters were analysed using routine laboratory techniques. Then cross-sectional analysis was performed.

RESULTS

Elevated levels of IS, indicators of kidney function, markers of inflammation and blood pressure values were observed in each CKD subgroups. There was no effect of antihypertensive therapy on IS levels between studied groups, as well as there was no clear relationship between IS and blood pressure values in each studied group. The positive associations between IS and Cu/Zn SOD, neopterin, hs-CRP, creatinine and neutrophils/lymphocytes ratio were observed in CKD-NONE and CKD-POLI subgroups. Additionally, in CKD-POLI group IS positively correlated with TNF-α, ferritin and neutrophils. In CKD-MONO group, IS was positively related to oxLDL-abs, neopterin, E-selectin and creatinine, whereas it was inversely associated with hs-CRP.

CONCLUSIONS

Our study showed for the first time that the antihypertensive therapy has no impact on IS levels in CKD patients with hypertension. However, the introduction of the antihypertensive therapy modified the dependencies between IS and the studied markers of kidney function, inflammation, oxidative stress and hematological parameters that are crucial for mortality and morbidity amongst the CKD patients with hypertension.

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.

Salivary Stress-Related Responses in Tinnitus: A Preliminary Study in Young Male Subjects with Tinnitus

Objective: This preliminary study examined if baseline measures of stress-related biomarkers as measured by salivary secretions of specific autonomic [measured by salivary α-amylase (sAA)], endocrine (measured by salivary cortisol), and immune (measured by salivary neopterin) responses are greater in male subjects with tinnitus in response to an induced-stress task.

Method: Twenty male subjects with no significant hearing loss, 10 with tinnitus, and 10 without tinnitus were enrolled in this study.Salivary secretions were collected before and after the induced stress task at four different time intervals.

Results: sAA levels were lower in the tinnitus group in comparison to subjects without tinnitus, suggesting impaired sympathetic activity in the subjects with tinnitus although these levels remained stable throughout the stress experiment.While no significant effects could be obtained for salivary cortisol or neopterin, salivary neopterin levels were trending toward significance over all measurements. Behavioral measures of stress were found to correlate negatively with measures of sAA and salivary neopterin.

Conclusion: The results of this study suggest impaired stress-related sAA mechanisms in male subjects with tinnitus, as evidenced by the different stress reactions induced in the endocrine system (as measured by salivary cortisol) and the immune system (as measured by salivary neopterin).

Cellular immune activity biomarker neopterin is associated hyperlipidemia: results from a large population-based study

BACKGROUND

Increased serum neopterin had been described in older age two decades ago. Neopterin is a biomarker of systemic adaptive immune activation that could be potentially implicated in metabolic syndrome (MetS). Measurements of waist circumference, triglycerides, high-density lipoprotein cholesterol (HDLC), systolic and diastolic blood pressure, glycated hemoglobin as components of MetS definition, and plasma total neopterin concentrations were performed in 594 participants recruited in the European Prospective Investigation into Cancer and Nutrition (EPIC).

RESULTS

Higher total neopterin concentrations were associated with reduced HDLC (9.7 %, p < 0.01 for men and 9.2 %, p < 0.01 for women), whereas no association was observed with the rest of the MetS components as well as with MetS overall (per 10 nmol/L: OR = 1.42, 95 % CI = 0.85-2.39 for men and OR = 1.38, 95 % CI = 0.79-2.43).

CONCLUSIONS

These data suggest that high total neopterin concentrations are cross-sectionally associated with reduced HDLC, but not with overall MetS.

Pathophysiological roles and clinical importance of biomarkers in acute coronary syndrome

Early diagnosis of acute coronary syndrome (ACS) is important to guide appropriate therapy at a time when it is most likely to be of value. Accurate prognostic and risk stratification will facilitate high-risk patients to have early advanced diagnostic investigations and early appropriate interventions in a cost-effective and efficient manner, while those patients at low risk of ACS complications do not need such costly diagnostic tests and unnecessary hospital admission. Recent investigations have demonstrated that elevation of biomarkers upstream from acute-phase biomarkers, biomarkers of plaque destabilization and rupture, biomarkers of myocardial ischemia, necrosis, and dysfunction may provide an earlier assessment of patient risk and identify patients with higher risk of having an adverse event. This review provides an overview of the pathophysiology and clinical characteristics of several well-established biomarkers as well as emerging biomarkers that may have potential clinical utility in patients with ACS. Such emerging biomarkers hold promise and need to be more thoroughly evaluated before utilization in routine clinical practice.

S, Cherian K. The clinical and biochemical parameters in relation to the serum neopterin levels in Indian children and adolescents

INTRODUCTION

An adverse pattern of blood lipids and cardiovascular abnormalities starts in obese children during childhood and neopterin serves as a marker for cardiovascular disease. Unfortunately, the data for children and adolescents, particularly, in the Indian population, are scarce. The present study aimed at evaluating the levels of serum neopterin in obese and overweight children and adolescents of the Indian population.

METHODS

The study groups included 296 school going children and adolescents. (96 obese and 97 overweight subjects were compared with 103 normal controls who were aged between 10-17 years). The anthropometric variables, the lipid profile, the fasting serum glucose which was analyzed by using an autoanalyzer and the serum neopterin levels were assayed by HPLC (Shimazdu) by using the method of Palfrey et al., 1993. The serum insulin levels were measured by using ELISA kits.

RESULTS

The serum neopterin levels (nmol/l) were elevated significantly in the obese (7.4±1.4) and overweight (6.4±0.8) (p<0.001) children and adolescents than in the controls (4.9±0.9). The serum neopterin levels showed a positive correlation with the BMI (r=0.79), WHR (r=0.5), systolic (r=0.44) and diastolic blood pressures (r= 0.25), insulin (r=0.57), HOMAIR (r=0.55), total cholesterol (r=0.35), triglycerides (r=0.20) and LDL-C (r=0.27) and they showed a negative correlation with HDL-C (r=-0.15) and fasting glucose (r= -0.3).

CONCLUSION

This study revealed a good relationship between serum neopterin and the anthropometric and biochemical parameters. We, therefore, aim to conduct regular camps at schools to counsel and advise the identified overweight and obese children to go for physical exercise and a balanced diet. The implementation of preventive measures from early childhood will have far reaching benefits, as even the prevalence of other obesity related disorders could decline.

Neopterin predicts the risk for fatal ischemic heart disease in type 2 diabetes mellitus: long-term follow-up of the HUNT 1 study

AIMS

Neopterin has emerged as a novel predictor of coronary events. The study aim was to compare the predictive value of neopterin and C-reactive protein (CRP) on long-term risk for fatal ischemic heart disease (IHD) in persons with newly diagnosed diabetes compared to persons without diabetes.

METHODS AND RESULTS

In 1984-1986 a large population study, HUNT 1, was conducted in Norway. During the study, 205 patients were diagnosed with formerly unknown diabetes. A matched control group without diabetes was selected from the HUNT 1 population. Fatal IHD was registered until 2004. Blood samples were drawn at baseline and serum was analysed for neopterin and CRP. Cox regression analysis with correction for age, gender, hypertension, body mass index, established cardiovascular disease and total cholesterol was used to estimate hazard ratios (HR) for fatal IHD. In the diabetes group, neopterin and CRP were independent predictors of fatal IHD, HR 2.59 (1.11-6.01) and 2.45 (1.05-5.69), respectively. Neither CRP nor neopterin were significant predictors of fatal IHD in the control group.

CONCLUSION

In subjects with diabetes, both neopterin and CRP were independent predictors of fatal IHD, suggesting that these two markers reflect different aspects of the pathogenesis underlying fatal coronary events.

Redox control of renal function and hypertension

Loss of redox homeostasis and formation of excessive free radicals play an important role in the pathogenesis of kidney disease and hypertension. Free radicals such as reactive oxygen species (ROS) are necessary in physiologic processes. However, loss of redox homeostasis contributes to proinflammatory and profibrotic pathways in the kidney, which in turn lead to reduced vascular compliance and proteinuria. The kidney is susceptible to the influence of various extracellular and intracellular cues, including the renin-angiotensin-aldosterone system (RAAS), hyperglycemia, lipid peroxidation, inflammatory cytokines, and growth factors. Redox control of kidney function is a dynamic process with reversible pro- and anti-free radical processes. The imbalance of redox homeostasis within the kidney is integral in hypertension and the progression of kidney disease. An emerging paradigm exists for renal redox contribution to hypertension.

Association between plasma thiols and immune activation marker neopterin in stable coronary heart disease

BACKGROUND

Studies have associated elevated plasma levels of the thiols homocysteine and cysteine with an increased risk of atherosclerosis. Their relationship with systemic inflammatory parameters and sclerosis scores was investigated in this study.

METHODS

Total homocysteine, total cysteine, neopterin and C-reactive protein (CRP) concentrations were measured in blood samples of 242 patients undergoing elective coronary angiography. A total of 181 patients had coronary artery disease (CAD), as defined by occlusion of > 75% of at least one of the three main coronary arteries, and 61 subjects did not have relevant coronary stenoses.

RESULTS

Total cysteine concentrations were higher in patients suffering from coronary artery sclerosis with stepwise increases relative to the extent of coronary artery sclerosis (p < 0.001). In contrast, neither total homocysteine nor the inflammatory markers, CRP and neopterin, differed between patients and controls. However, total homocysteine concentrations correlated with total cysteine (r = 0.468) and neopterin concentrations (r = 0.290), as well as serum creatinine (r = 0.226; all p < 0.001), the latter indicating a dependence of total homocysteine concentrations on kidney function. Total cysteine concentrations were associated with increased neopterin levels (r = 0.231, p < 0.001).

CONCLUSIONS

Total cysteine concentrations were well suited to estimate the extent of coronary artery sclerosis, while in our study of stable CAD patients total homocysteine was not increased compared to controls. The association between homocysteine, cysteine and parameters of immune activation and inflammation in our study suggests that these markers of CAD may be interdependent.

Elevated serum neopterin levels and adverse cardiac events at 6 months follow-up in Mediterranean patients with non-ST-segment elevation acute coronary syndrome

BACKGROUND

Little information exists regarding the prognostic role of biomarkers of inflammation in Mediterranean patients. High C-reactive protein and neopterin levels - a marker of macrophage activation - predict cardiovascular events in stable angina patients and patients with acute coronary syndromes (ACS). We sought to assess whether plasma neopterin levels predict adverse clinical outcomes in Mediterranean patients with non-ST elevation (NSTE) ACS, i.e. unstable angina (UA) and NSTE myocardial infarction (MI).

METHODS

We prospectively assessed 397 patients (74% men) admitted with NSTEACS, 147 (37%) had unstable angina and 250 (63%) NSTEMI. Blood samples for neopterin and CRP assessment were obtained at admission. The study endpoint was the composite of cardiac death, acute myocardial infarction and unstable angina at 180 days.

RESULTS

Baseline neopterin concentrations (nmol/L) were similar in unstable angina and NSTEMI patients (8.3 [6.6-10.7] vs. 7.9 [6.2-10.9]; p=0.4). Fifty-nine patients (14.9%) had events during follow-up. Twenty-nine (21.5%) patients with neopterin levels in the highest third experienced the combined endpoint, compared to 30 (11.5%) patients with neopterin levels in the second and the lowest thirds (log-rank 7.435, p=0.024). On multivariable hazard Cox regression, neopterin (highest vs. 1st and 2nd thirds, HR 1.762, 95% CI [1.023-3.036]) was independently associated with the combined endpoint.

CONCLUSION

Increased neopterin levels are an independent predictor of 180-day adverse cardiac events in Mediterranean patients with NSTEACS.

Elevated levels of neopterin in sleep-disordered breathing

BACKGROUND

Sleep-disordered breathing (SDB) is increasingly being recognized as an independent risk factor for hypertension and cardiovascular disease. Recent evidence suggests that the maladaptive physiologic response to SDB, particularly cardiovascular effects, may result in part from systemic inflammation. Although abnormal cytokine levels have been documented in SDB, data on whether SDB is associated with cellular activation are limited. Thus, this investigation sought to determine whether neopterin, a marker released by activated macrophages, is increased in SDB.

METHODS AND RESULTS

Fifty-five men, free of medical comorbidity, undergoing polysomnography had fasting serum tested for neopterin levels. Multivariable regression methods were used to quantify the association between neopterin and quartiles of the apnea hypopnea index (AHI) while accounting for body mass index, waist circumference, and percentage of body fat. Quartiles of AHI (I: < 3.83 events per hour; II: 3.83 to 11.98 events per hour; III: 11.99 to 36.82 events per hour; IV > 36.82 events per hour) indicated a range from no SDB through severe SDB. Compared to the subjects in the first AHI quartile, serum neopterin levels were higher by 3.0%, 10.9%, and 26.5% in the second, third, and fourth AHI quartiles, respectively (p < 0.001for linear trend). Neopterin levels also were higher in those with greater degree of sleep-related hypoxemia, more stage 1 sleep, and less stage 2 sleep.

CONCLUSION

The results of this study indicate that severity of SDB independently associates with serum levels of neopterin, a marker for macrophage activation that may play an important role in the pathogenesis of SDB-related cardiovascular disease.

Alterations in serum neopterin correlate with thrombolysis in myocardial infarction risk scores in acute coronary syndromes

OBJECTIVES

Using serum neopterin as a marker of macrophage activation, we sought to examine the relationship between serum neopterin levels, thrombolysis in myocardial infarction (TIMI) risk scores, and how different treatments of acute coronary syndromes affect change in neopterin.

METHODS

We examined serum neopterin concentrations at presentation and 72 h after treatment in 70 patients with acute coronary syndromes (35 with medical therapy, 25 with uncoated coronary stents, and 10 received rapamycin-eluting stents) using a commercially available immunoassay. Serum neopterin levels were determined for 36 patients with stable coronary artery disease. TIMI risk scores were calculated when appropriate (n=58).

RESULTS

Serum neopterin had a strong correlation with the TIMI risk score on admission (P<0.0001). The mean baseline neopterin levels in patients with acute coronary syndromes stratified with TIMI scores between 1 and 7 were the following: patients with TIMI 1 scores had a level of 3.3+/-0.4 nmol/l, TIMI 2 patients 4.6+/-0.6 nmol/l, TIMI 3 patients 5.5+/-1.4 nmol/l, TIMI 4 patients 7.5+/-2.4 nmol/l, TIMI 5 patients 10.8+/-3.3 nmol/l, TIMI 6 patients 17.5+/-4.0 nmol/l, and TIMI 7 patients 23.0+/-7.1 nmol/l. Mean changes in serum neopterin were significantly higher for the uncoated stent group than for each of the other three groups (P<0.05).

CONCLUSIONS

Serum neopterin concentrations have a high correlation with TIMI risk scores and may represent a marker useful in stratifying patients with acute coronary syndromes. Our results also suggest that the use of uncoated coronary stents results in macrophage activation not found with other treatment modalities.

Usefulness of neopterin levels and left ventricular function for risk assessment in survivors of acute myocardial infarction

BACKGROUND

Results of previous studies have shown that serum neopterin levels are higher in patients with acute myocardial infarction (AMI). However, little is known regarding the prognostic value of neopterin in survivors of AMI. The present study analyzes the prognostic value of neopterin serum concentration and left ventricular ejection fraction in survivors of AMI.

METHODS

The additional prognostic information provided by neopterin to parameters of left ventricular function in survivors of AMI was investigated through 82 patients with ST-segment elevation.

RESULTS

Binary logistic regression analysis identified the following predictors of 6-month cardiac death: Killip class >I at presentation (OR=2.4, 95% CI: 1.2 to 3.8, p=0.001), a reduced ejection fraction (OR=1.9, 95% CI: 1.3 to 2.2, p=0.001), and greater neopterin (OR=1.4, 95% CI: 1.1 to 1.6, p=0.01).

CONCLUSIONS

Neopterin is associated with mortality, in addition to parameters of ventricular function (Killip class and ejection fraction) in survivors of AMI.

Mechanism of neopterin-induced myocardial dysfunction in the isolated perfused rat heart

Neopterin is a sensitive marker for diseases involving increased activity of the cellular immune system in humans. Many studies, however, provide evidence for neopterin not only as a marker, but also for its characteristic effects. Recently, we were able to demonstrate a considerable influence of exogenous neopterin at a concentration of 100 mumol/l on cardiac performance in the Langendorff model of isolated perfused rat hearts. The present study was designed to investigate its possible mechanism. During co-infusion of neopterin at a concentration of 100 mumol/l with the unspecific nitric oxide synthase inhibitor N(G)-monomethyl-l-arginine monoacetate, the nitric oxide donor PAPA NONOate, the free radical scavenger N-acetylcysteine, or the pro-inflammatory cytokine tumor necrosis factor-alpha the effects on cardiac contractility parameters and coronary vascular resistance were studied in 67 male Sprague-Dawley rats. The temperature-controlled and pressure-constant Langendorff apparatus was used with retrograde perfusion of the aorta and a Krebs-Henseleit buffer. Neither the unspecific nitric oxide synthase inhibitor nor the nitric oxide donor excludes nitric oxide from playing a mechanistic role in our perfusion studies. Tumor necrosis factor-alpha was without any synergistic or antagonistic effects when co-treated with neopterin. N-acetylcysteine was most effective in abolishing neopterin-dependent effects on cardiac function. The negative effects of neopterin on cardiac performance might be due to an enhancement of oxidative stress by neopterin that can be attenuated by the antioxidant N-acetylcysteine. Neopterin has to be considered a pathogenic factor in the development of cardiac dysfunction in chronic disease states with high neopterin levels secondary to activation of the immune system.

Resveratrol suppresses interferon-gamma-induced biochemical pathways in human peripheral blood mononuclear cells in vitro

A wide range of biological activities of resveratrol (3,5,4'-trihydroxystilbene) in vitro and in vivo has been proved, including antioxidant, antitumor, and also anti-inflammatory effects. Resveratrol found in, e.g., grapes and red wine has been suggested to counteract the progression of coronary heart disease by lowering serum lipid concentrations and inhibiting platelet aggregation. Cellular immune activation is known to be involved crucially in the pathogenesis of coronary heart diseases. In this in vitro study, the modulatory effect of resveratrol on two interferon-gamma-mediated pathways, the degradation of tryptophan by the enzyme indoleamine 2,3-dioxygenase, and the production of neopterin by activation of the GTP-cyclohydrolase I, was tested. Cultures of human peripheral blood mononuclear cells were exposed to resveratrol, in combination with mitogenic stimulation. A significant down-regulatory effect of resveratrol on both biochemical pathways was found, and also the production of Th1-type cytokine interferon-gamma was significantly suppressed. If these results can be verified in vivo, an explanation is provided how resveratrol may interfere with immune activation and cytokine cascades, which are important in the development and progression of cardiovascular disorders and also other diseases.

Elevated serum neopterin predicts future adverse cardiac events in patients with chronic stable angina pectoris

AIMS

Serum levels of neopterin, an immune modulator secreted by activated macrophages, are elevated in patients with acute coronary syndromes compared with stable angina patients and control subjects. In unstable angina, serum neopterin levels correlate with the presence of vulnerable coronary stenosis, multiple complex coronary lesions, and patient outcome. The present study assessed the prognostic significance of raised serum neopterin concentrations in patients with stable angina pectoris.

METHODS AND RESULTS

We carried out a 1-year follow-up prospective study in 297 patients with chronic stable chest pain undergoing diagnostic coronary angiography. The primary study endpoint was the composite of non-fatal myocardial infarction, unstable angina, and cardiac death. Fifty-one patients (17.2%) had adverse coronary events during follow-up. Mean serum neopterin levels were significantly higher in patients with events compared with those without (P=0.02). On multiple regression analysis, neopterin levels (P=0.021), severity of coronary artery disease (P=0.009), and a history of previous myocardial infarction (P=0.001) were independent predictors of adverse events.

CONCLUSIONS

Serum neopterin is an independent predictor of major adverse coronary events in patients with chronic stable angina pectoris. This marker of macrophage activation may be useful for risk stratification in patients with chronic stable angina.

Anti-inflammatory compound resveratrol suppresses homocysteine formation in stimulated human peripheral blood mononuclear cells in vitro

Inflammation, immune activation and oxidative stress play a major role in the pathogenesis of cardiovascular disorders. In addition to markers of inflammation, moderate hyperhomocysteinemia is an independent risk factor for cardiovascular disease, and there is a link between the activation of immunocompetent cells and the enhanced formation of homocysteine in vitro. Likewise, anti-inflammatory drugs and nutrients rich in antioxidant vitamins are able to reduce cardiovascular risk and to slow down the atherogenic process. Resveratrol, a phenolic antioxidant synthesized in grapes and vegetables and present in wine, has also been supposed to be beneficial for the prevention of cardiovascular events. Apart from its strong antioxidant properties, resveratrol has also been demonstrated to act as an anti-inflammatory agent. In this study the influence of resveratrol on the production of homocysteine by stimulated human peripheral blood mononuclear cells (PBMCs) was investigated. Results were compared to earlier described effects of the anti-inflammatory compounds aspirin and salicylic acid and of the lipid-lowering drug atorvastatin. Stimulation of PBMCs with the mitogens concanavalin A and phytohemagglutinin induced significantly higher homocysteine accumulation in supernatants compared with unstimulated cells. Treatment with 10–100μM resveratrol suppressed homocysteine formation in a dose-dependent manner. Resveratrol did not influence the release of homocysteine from resting PBMCs. The data suggest that resveratrol may prevent homocysteine accumulation in the blood by suppressing immune activation cascades and the proliferation of mitogen-driven T-cells. The effect of resveratrol to down-regulate the release of homo-cysteine was comparable to the decline of neopterin concentrations in the same experiments. The suppressive effect of resveratrol was very similar to results obtained earlier with aspirin, salicylic acid and atorvastatin; however, it appeared that doses of compounds needed to reduce homocysteine levels to 50% of stimulated cells were always slightly lower than those necessary to achieve the same effect on neopterin concentrations. The influence of resveratrol and of all the other compounds on homocysteine production appears to be independent of any direct effect on homocysteine biochemistry.

Markers of Inflammation and Rapid Coronary Artery Disease Progression in Patients With Stable Angina Pectoris

BACKGROUND

Both endothelial cell activation and macrophage activation play a significant role in atherogenesis and atheromatous plaque vulnerability and may determine rapid coronary artery disease (CAD) progression. We sought to assess the association between serum inflammatory markers and rapid CAD progression in patients with chronic stable angina pectoris.

METHODS AND RESULTS

We studied 124 chronic stable angina pectoris patients (84 men; mean age, 61+/-10 years) who were on a waiting list for coronary angioplasty for a mean time of 4.8+/-2.4 months. CAD progression was defined as > or =10% diameter reduction of a pre-existing stenosis > or =50%, > or =30% diameter reduction of a stenosis <50%, development of a new stenosis > or =30% in a previously normal segment, or progression of any stenosis to total occlusion. CAD progression occurred in 35 patients (28%). After adjustment with binary logistic regression, neopterin (P<0.001), high-sensitivity C-reactive protein (P=0.017), matrix metalloproteinase-9 (P=0.002), soluble intercellular adhesion molecule 1 (P<0.001), and previous history of unstable angina (P=0.01) were independent predictors of rapid CAD progression. The association between rapid disease progression and inflammatory markers remained significant even when presence of complex lesions was introduced into the multivariate model.

CONCLUSIONS

Rapid CAD progression in patients with stable angina pectoris is associated with increased C-reactive protein levels and raised concentrations of biochemical markers of endothelial and macrophage activation.