Inflammatory and thrombotic mechanisms in coronary atherosclerosis

Constitutive induction of pro-inflammatory and chemotactic cytokines in cystathionine beta-synthase deficient homocystinuria

Cystathionine beta-synthase (CBS) deficient homocystinuria (HCU) is an inherited metabolic defect that if untreated, typically results in cognitive impairment, connective tissue disturbances, atherosclerosis and thromboembolic disease. In recent years, chronic inappropriate expression of the inflammatory response has emerged as a major driving force of both thrombosis and atherosclerotic lesion development. We report here a characterization of the abnormalities in cytokine expression induced in both a mouse model of HCU and human subjects with the disease in the presence and absence of homocysteine lowering therapy. HCU mice exhibited highly significant induction of the pro-inflammatory cytokines Il-1alpha, Il-1beta and TNF-alpha. Similarly, in untreated/poorly compliant human subjects with HCU we observed constitutive induction of multiple pro-inflammatory cytokines (IL-1alpha, IL-6, TNF-alpha, Il-17 and IL-12(p70)) and chemotactic chemokines (fractalkine, MIP-1alpha and MIP-1beta) compared to normal controls. These HCU patients also exhibited significant induction of IL-9, TGF-alpha and G-CSF. The expression levels of anti-inflammatory cytokines were unaffected in both HCU mice and human subjects with the disease. In the human subjects, homocysteine lowering therapy was associated with either normalization or significant reduction of all of the pro-inflammatory cytokines and chemokines investigated. We conclude that HCU is a disease of chronic inflammation and that aberrant cytokine expression has the potential to contribute to multiple aspects of pathogenesis. Our findings indicate that anti-inflammatory strategies could serve as a useful adjuvant therapy for this disease.

A topographical map of the causal network of mechanisms underlying the relationship between major depressive disorder and coronary heart disease

OBJECTIVE

Major depressive disorder (MDD) and coronary heart disease (CHD) are both clinically important public health problems. Depression is linked with a higher incidence of ischaemic cardiac events and MDD is more prevalent in patients with CHD. No single comprehensive model has yet described the causal mechanisms linking MDD to CHD. Several key mechanisms have been put forward, comprising behavioural mechanisms, genetic mechanisms, dysregulation of immune mechanisms, coagulation abnormalities and vascular endothelial dysfunction, polyunsaturated omega-3 free fatty acid deficiency, and autonomic mechanisms. It has been suggested that these mechanisms form a network, which links MDD and CHD. The aim of this review is to examine the causal mechanisms underlying the relationship between MDD and CHD, with the aim of constructing a topological map of the causal network which describes the relationship between MDD and CHD.

METHODS

The search term 'depression and heart disease' was entered into an electronic multiple database search engine. Abstracts were screened for relevance and individually selected articles were collated.

RESULTS

This review introduces the first topological map of the causal network which describes the relationship between MDD and CHD.

CONCLUSIONS

Viewing the causal pathways as an interdependent network presents a new paradigm in this field and provides fertile ground for further research. The causal network can be studied using the methodology of systems biology, which is briefly introduced. Future research should focus on the creation of a more comprehensive topological map of the causal network and the quantification of the activity between each node of the causal network.

Inflammation and thrombosis in diabetes

Patients with diabetes mellitus are at increased risk of cardiovascular morbidity and mortality. Atherothrombosis, defined as atherosclerotic lesion disruption with superimposed thrombus formation, is the most common cause of death among these patients. Following plaque rupture, adherence of platelets is followed by local activation of coagulation, the formation of a cross-linked fibrin clot and the development of an occlusive platelet rich fibrin mesh. Patients with diabetes exhibit a thrombotic risk clustering which is composed of hyper-reactive platelets, up regulation of pro-thrombotic markers and suppression of fibrinolysis. These changes are mainly mediated by the presence of insulin resistance and dysglycaemia and an increased inflammatory state which directly affects platelet function, coagulation factors and clot structure. This prothrombotic state is related to increased cardiovascular risk and may account for the reduced response to antithrombotic therapeutic approaches, underpinning the need for adequate antithrombotic therapy in patients with diabetes to reduce their cardiovascular mortality.

Analgesic and Anti-Inflammatory Activities of the Methanol Extract from Pogostemon cablin

Pogostemon cablin (PC) is a herbal medicine traditionally applied to treat not only common cold, nausea and diarrhea but also headache and fever. The aim of this study was to investigate the analgesic and anti-inflammatory properties of standardized PC methanol extract (PCMeOH) in vivo. Investigations were performed in mice with two analgesic models. One was acetic acid-induced writhing response and the other formalin-induced paw licking. The anti-inflammatory effect was tested by λ-carrageenan (Carr)-induced mice paw edema. These analgesic experimental results indicated that PCMeOH (1.0 g/kg) decreased the acetic acid-induced writhing responses and PCMeOH (0.5 and 1.0 g/kg) decreased the licking time in the second phase of the formalin test. Moreover, Carr-induced paw edema inflammation was significantly reduced in a dose-dependent manner when PCMeOH (0.5 and 1.0 g/kg) was administered 3 and 4 h after the Carr injection. Mechanistic studies showed that PCMeOH decreased the levels of malondialdehyde in the edema paw by increasing the activities of anti-oxidant enzymes, such as superoxide dismutase, glutathione peroxidase and glutathione reductase, in the liver and decreasing the cyclooxygenase 2 and tumor necrosis factor-α activities in the edema paw. This study has demonstrated the analgesic and anti-inflammatory effects of PCMeOH, thus verifying its popular use in traditional medicine.

Ultra-Sensitive C-Reactive Protein (US-CRP) in Patients With Periodontal Disease and Risk of Acute Myocardial Infarction

BACKGROUND

The purpose of this study was to determine if the US-CRP values associated with periodontal disease are risk markers for Acute Myocardial Infarction (AMI) and to determine if the US-CRP levels associated with recent AMI are higher in patients with Periodontal disease.

METHODS

In order to meet the goal of the study, a case control study design was conducted. The analysis sample consisted of 401 adults (30 - 75 years old), living in Bogota D.C., Colombia, from the Hospital Universitario San Ignacio, the Faculty of Dentistry at the Pontificia Universidad Javeriana, and the Fundacion Cardio Infantil. Patients with current infections, antibiotic use in the last 3 months, periodontal treatment at least six months before the baseline of this study, mouth ulcerations caused by any type of prosthesis, candidiasis, stomatitis, or less than 7 teeth in mouth were excluded. Periodontal examination for the case group and the control group was conducted by three previously calibrated examiners. Periodontal disease was diagnosed by the presence of bleeding on probing and attachment loss. The Chronic Periodontitis diagnosis was confirmed with these clinical signs, according to the 1999 Armitage classification. The assessment of the US-CRP was performed using the IMMULITE method containing one monoclonal and one polyclonal anti-CRP antibody. This method provides a measurement range of 0.1 - 500 mg/L. Statistical analysis of variables was performed with OR and confidence intervals. A multivariate analysis was performed to determine the association between the US-CRP increase, periodontal disease and acute myocardial infarction, adjusting for smoking and other confounding factors identified in the analysis.

RESULTS

The study population was constituted by 401 patients, 56.1% (225) males, with a mean age of 52.6. When groups were compared it was observed that, in those patients with AMI and chronic severe or moderate periodontitis, 24.2% had HDL-C values lower than 40 mg/dl, 78.8% had LDL-C values higher than 100 mg/dl, 55.2% had triglycerides over 150 mg/dl, and US-CRP over 2 mg/L in 53.3%.

CONCLUSIONS

Periodontal disease (moderate, severe, and chronic periodontal disease) may increase the risk of Acute Myocardial Infarction (AMI) by increasing the US-CRP levels.

Involvement of Depressive Catecholamines as Thrombosis Risk/Inflammatory Markers in Non-Smoker, Non-Obese Congestive Heart Failure, Linked to Increased Epidermal Growth Factor-Receptor (EGF-R) Production

The EGF-R, also known as HER-1 or erbB-1 (EGF-R/HER-1/erbB-1), is a member of the human epithelial receptor tyrosine kinase family. sEGF-R is considered to play a role in cardiac (patho)physiology. We aimed to investigate whether soluble EGF-R is increased in congestive heart failure (CHF) patients and if related to disease severity. Soluble EGF-R, vitamin D, parathyroid hormone (PTH) was studied, and being evaluated in relation to Ca(2+), lipids, hsCRP, fibrinogen, serotonin, norepinepherine (NE). The study compared non-smoker, non-obese male CHF patients (n = 50) with age and gender-matched essential hypertension (HTN) patients (n = 20). Moreover, comparison with healthy control volunteers (n = 20) were employed. EGF-R/HER-1/erbB-1 was higher (P = 0.013) in 50 CHF male patients mean 12 ± 0.7 fmol/ml, than in 20 HTN, 9.25 ± 0.6 fmol/ml or in 20 controls, 6.25 ± 1 fmol/ml. Serum EGF-R levels correlated positively with hsCRP and NE, and were highest among CVD patients (n = 70) as well as negatively with vitamin D and HDL-C. EGF-R/HER-1/erbB-1 levels are increased in HTN and more in CHF patients. This study confirms a strong association between catecholamines as well as EGF-R/HER-1/erbB-1 levels with PTH and low vitamin D levels, being related to hyperlipidemia and inflammation (hsCRP and fibrinogen) in CVD. Moreover, contributing to the complex process of the inflammatory component of atherosclerosis in hypertensive patients that leads eventually to CHF.

CALU A29809G polymorphism in coronary atherothrombosis: Implications for coronary calcification and prognosis

INTRODUCTION

Arterial calcification is a risk factor for atherosclerosis. Calumenin (CALU), a protein regulating proteins involved in coagulation and arterial calcification also has extracellular functions related to atherosclerosis. We recently described that CALU polymorphism A29809G was related to acenocoumarol requirements, and we wanted to evaluate its role in arterial calcification and prognosis.

PATIENTS AND METHODS

A total of 374 consecutive patients with non-ST-elevation acute coronary syndrome (nSTACS). In 175 of them, who underwent percutaneous coronary intervention, we assessed calcification in each main coronary artery. Follow-up at 1 and 6 months was performed for adverse end-points.

RESULTS

CALU 29809G carriers were more frequent in the low calcium group (P = 0.037). The presence of >or=3 cardiovascular risk factors and CALU polymorphism were associated with arterial calcification (OR 2.34, P = 0.049; and OR 0.34, P = 0.019, respectively). CALU 29809G allele was the only variable associated with events at 1 month (HR 0.42; P = 0.042). Multivariate analysis showed that, at 6 months, age and severe anginal symptoms were associated with worse prognosis (HR 2.13, P = 0.023; and HR 2.01, P = 0.011, respectively), whereas CALU 29809G allele associated with good prognosis (HR 0.59, P = 0.044). Our results suggest that CALU A29809G is associated with arterial calcification and short-term prognosis of the outcome of patients with nSTACS.

The peripheral blood mononuclear cell microRNA signature of coronary artery disease

BACKGROUND

MicroRNAs are being used in the oncology field to characterize tumors and predict the survival of cancer patients. Here, we explored the potential of microRNAs as biomarkers for coronary artery disease (CAD) and acute coronary syndromes.

METHODS AND RESULTS

Using real-time PCR-based profiling, we determined the microRNA signature of peripheral blood mononuclear cells (PBMCs) from stable and unstable CAD patients and unaffected controls. 129 of 157 microRNAs measured were expressed by PBMCs and low variability between separate PBMC pools was observed. The presence of CAD in general coincided with a marked 5-fold increase (P<0.001) in the relative expression level of miR-135a, while the expression of miR-147 was 4-fold decreased (P<0.05) in PBMCs from CAD patients as compared to controls, resulting in a 19-fold higher miR-135a/miR-147 ratio (P<0.001) in CAD. MicroRNA/target gene/biological function linkage analysis suggested that the change in PBMC microRNA signature in CAD patients is probably associated with a change in intracellular cadherin/Wnt signaling. Interestingly, unstable angina pectoris patients could be discriminated from stable patients based upon their relatively high expression level of a cluster of three microRNAs including miR-134, miR-198, and miR-370, suggesting that the microRNA signatures can be used to identify patients at risk for acute coronary syndromes.

CONCLUSIONS

The present study is the first to show that microRNA signatures can possibly be utilized to identify patients exhibiting atherosclerotic CAD in general and those at risk for acute coronary syndromes. Our findings highlight the importance of microRNAs signatures as novel tool to predict clinical disease outcomes.

Atherosclerosis, inflammation and Chlamydia pneumoniae

Coronary heart disease is the single most common cause of illness and death in the developed world. Coronary atherosclerosis is by far the most frequent cause of ischemic heart disease, and plaque disruption with superimposed thrombosis is the main cause of the acute coronary syndromes of unstable angina, myocardial infarction, and sudden death. Atherosclerosis is the result of a complex interaction between blood elements, disturbed flow, and vessel wall abnormality, involving several pathological processes: inflammation, with increased endothelial permeability, endothelial activation, and monocyte recruitment; growth, with smooth muscle cell proliferation, migration, and matrix synthesis; degeneration, with lipid accumulation; necrosis, possibly related to the cytotoxic effect of oxidized lipid; calcification/ossification, which may represent an active rather than a dystrophic process; and thrombosis, with platelet recruitment and fibrin formation. In this review we discuss these processes and the possible pathological effects of Chlamydia infection and the ensuing phlogosis.

Association between periodontal diseases and systemic diseases

Current evidence suggests that periodontal disease may be associated with systemic diseases. This paper reviewed the published data about the relationship between periodontal disease and cardiovascular diseases, adverse pregnancy outcomes, diabetes and respiratory diseases, focusing on studies conducted in the Brazilian population. Only a few studies were found in the literature focusing on Brazilians (3 concerning cardiovascular disease, 7 about pregnancy outcomes, 9 about diabetes and one regarding pneumonia). Although the majority of them observed an association between periodontitis and systemic conditions, a causal relationship still needs to be demonstrated. Further studies, particularly interventional well-designed investigations, with larger sample sizes, need to be conducted in Brazilian populations.

Elevated serum cytokines during human anaphylaxis: Identification of potential mediators of acute allergic reactions

BACKGROUND

Anaphylaxis is generally unanticipated and requires emergency management. Therefore, the biological mediators in human beings have been difficult to define.

OBJECTIVE

Our aim was to identify cytokines and chemokines whose concentrations increase during anaphylaxis in human beings and to determine how each correlates with severity.

METHODS

We measured the concentrations of potential mediators, including cytokines, chemokines, mast cell tryptase (MCT), and histamine, over 3 time points in 76 patients presenting to emergency departments with anaphylaxis and correlated these with a global severity scale, hypotension, and hypoxia.

RESULTS

IL-2, IL-6, IL-10, TNF receptor I, MCT, and histamine were significantly elevated in patients with severe reactions (n = 36) compared with moderate reactions (n = 40) and healthy controls. Histamine levels peaked at emergency department arrival, whereas other mediators peaked later. IL-4, IL-5, IL-13, IFN-gamma, and TNF-alpha were marginally elevated in severe reactions compared with healthy controls but did not correlate with reaction severity. Severe reactions tended to be either hypotensive (n = 19) or hypoxemic (n = 12). Levels of IL-6, IL-10, TNF receptor I, MCT, and histamine correlated with hypotension. No mediator correlated with hypoxemia or other respiratory features.

CONCLUSION

This study confirms that the concentrations of a number of cytokines are elevated in blood during anaphylaxis in human beings and that some correlate with the presence of hypotension. Others were only marginally elevated within a concentration range that available assays do not reliably detect. During respiratory reactions, mediators may be largely confined to the airways so that blood concentrations do not reflect activity.

Oxidative stress and platelet activation: markers of myocardial infarction in type 2 diabetes mellitus

We compared lipids, lipid peroxidation product malondialdehyde (MDA), the acute phase reactant high-sensitivity C-reactive protein (hsCRP), interleukin 1beta (IL-1beta), and platelet selectin (P-selectin) between healthy controls, type 2 diabetes mellitus (DM) participants without myocardial infarction (MI), as well as type 2 DM participants with MI. Malondialdehyde, IL-1beta, and P-selectin levels were significantly higher in the diabetic participants with MI than in either healthy controls or diabetic participants without MI. In the diabetic groups, fasting blood glucose (FBG) level, glycated hemoglobin (HbA(1c)), MDA, hsCRP, and P-selectin were all significantly positively correlated with each other. This study suggests that increased levels of oxidative stress markers, proinflammatory markers, and adhesion molecules contribute to the atherosclerotic process that eventually leads to coronary artery disease in diabetic patients.

Prevalence, predictors and outcome of vascular damage in systemic lupus erythematosus

Despite improved prognosis, patients with systemic lupus erythematosus (SLE) remain at increased risk for early death. Vascular events (VE) occur with increased frequency and contribute to premature death in SLE patients. As conventional cardiovascular risk factors do not fully explain this hazard, this study investigated the contribution of disease-specific features to VE development. Documented VE were classified as atherothrombotic, venous thrombotic, arterial thrombotic or tissue loss inducing vasculitis during a mean follow-up of nearly 12 years in the Tromsø Lupus cohort ( n = 158). The impact of disease-specific factors (organ manifestations, laboratory findings, drug treatment, weighted average SLE Disease Activity Index (WAS) and cumulative Damage Index) was assessed by odds ratios for VE in multivariate analysis. A total of 41 patients (26%) developed VE, and atherothrombotic events were most common (73%). Overall, VE prevalence was 3.5/100 patient years, and VE risk increased linearly over time, reaching 35% after 20 years. WAS scores >3 increased, and use of hydroxychloroquine and antihypertensive medication reduced overall VE risk. Age >40 years was the main risk factor for atherothrombotic events. VE nearly quadrupled the risk of death. VE occurred in 26% of SLE patients, predominantly as atherothrombotic disease. VE prevalence increased linearly over time leading to a four-fold risk of mortality. Strategies for reducing disease activity, including treatment with antimalarials and antihypertensive drugs, are most likely to reduce the risk associated with VE in SLE.

CagA antigen of Helicobacter pylori and coronary instability: insight from a clinico-pathological study and a meta-analysis of 4241 cases

BACKGROUND

Cytotoxin-associated gene-A (CagA) antigen is expressed by some virulent strains of Helicobacter pylori (H. pylori). The role of CagA antigen in coronary instability is unknown. We performed a clinico-pathological study and a meta-analysis in the attempt to shed new light on this complex issue.

METHODS

In the clinico-pathological study, 38 patients with unstable angina (UA), 25 patients with stable angina (SA), 21 patients with normal coronary arteries (NCA) and 50 age and sex matched healthy volunteers were enrolled. Serology for CagA was assessed in all patients. Specimens of atherosclerotic plaques were obtained from all patients by directional coronary atherectomy, and prepared for immunohistochemistry using anti-CagA monoclonal antibodies. The meta-analysis includes 9 studies assessing the association between seropositivity to CagA strains and acute coronary events.

RESULTS

The titre of anti-CagA antibodies was significantly higher in patients with unstable angina (161+/-90 RU/ml) compared to those with stable angina (83+/-59 RU/ml p<0.02), NCA (47.3+/-29 RU/ml p<0.01) and healthy controls (73+/-69 p<0.02). Anti-CagA antibodies recognized antigens localized inside coronary atherosclerotic plaques in all specimens from both stable and unstable patients. In the meta-analysis, seropositivity to CagA was significantly associated with the occurrence of acute coronary events with an odds ratio (OR) of 1.34 (95% CI, 1.15-1.58, p=0.0003).

CONCLUSIONS

Taken together these findings suggest that in a subset of patients with unstable angina, an intense immune response against CagA-positive H. pylori strains might be critical to precipitate coronary instability mediated by antigen mimicry between CagA antigen and a protein contained in coronary atherosclerotic plaques.

Proteomic analysis of differential protein expression in atherosclerosis

Although recent studies have shown that several pro-inflammatory proteins can be used as biomarkers for atherosclerosis, the mechanism of atherogenesis is unclear and little information is available regarding proteins involved in development of the disease. Atherosclerotic tissue samples were collected from patients in order to identify the proteins involved in atherogenesis. The protein expression profile of atherosclerosis patients was analysed using two-dimensional electrophoresis-based proteomics. Thirty-nine proteins were detected that were differentially expressed in the atherosclerotic aorta compared with the normal aorta. Twenty-seven of these proteins were identified in the MS-FIT database. They are involved in a number of biological processes, including calcium-mediated processes, migration of vascular smooth muscle cells, matrix metalloproteinase activation and regulation of pro-inflammatory cytokines. Confirmation of differential protein expression was performed by Western blot analysis. Potential applications of the results include the identification and characterization of signalling pathways involved in atherogenesis, and further exploration of the role of selected identified proteins in atherosclerosis.

Inflammatory and thrombotic processes are associated with vascular dysfunction in children with familial hypercholesterolemia

BACKGROUND

Evidence suggests that children with familial hypercholesterolemia (FH) have endothelial dysfunction. Inflammatory and haemostatic abnormalities are associated with advanced atherosclerosis and increased cardiovascular events. However, it is unknown whether these abnormalities present in FH children and contribute to their vascular dysfunction.

METHODS AND RESULTS

We studied 38 children with FH (19 males, 19 females aged 14.8+/-0.9 years mean+/-S.E.) and 41 healthy children (controls; 22 males, 19 females aged 15.4+/-0.7 years). Endothelium-dependent reactive hyperemia (RH%) and endothelium-independent nitrate hyperemia dilatation (NH%) were measured by strain gauge plethysmography. Inflammatory and haemostatic parameters were assessed by ELISA. RH% and NH% were significantly reduced in FH compared to controls (91.3+/-9.3% vs. 120.4+/-10.6% and 53.6+/-3.8% vs. 74.5+/-7.4%, p<0.05 for both). Total cholesterol and lipoprotein (a) were increased in FH children compared to controls (282.3+/-8.8 mg/dl vs. 163.8+/-4.6 mg/dl and 11.0[4.6, 30.7]mg/dl vs. 5.24[2.63, 11.0]mg/dl median [IQR] respectively; p<0.001 for both). Intercellular cell adhesion molecule (ICAM-1) and interleukin 1 beta (IL-1 beta) serum levels were increased in FH compared to controls (p<0.05 and <0.001, respectively). Plasminogen activator inhibitor 1 (PAI-1) levels were also higher in FH children (p<0.001). Multivariate analysis revealed that reactive hyperemia was independently associated with nitrate-dependent reactive hyperemia (beta=0.597(0.199), p<0.01), PAI-1(beta=-6.78(2.65), p<0.05), log IL-1 beta (beta=-102.8 (30.2), p<0.01), age (beta=-5.06 (2.35), p<0.05) and FH status (beta=-25.2(10.6), p<0.05) (R(2) for the model: 0.63, p=0.001).

CONCLUSIONS

Inflammatory and haemostatic abnormalities are present in FH children and contribute to the endothelial dysfunction observed in these children.

Role of pro-/anti-inflammatory cytokines and their correlation with established risk factors in South Indians with coronary artery disease

Cytokines are responsible for the modulation of immunological and inflammatory processes and play a significant role in the pathogenesis of coronary artery disease. We estimated the levels of pro-/anti-inflammatory cytokines in South Indian patients with coronary artery disease. The study population comprised of groups 1-3: 100 patients each with acute myocardial infarction, unstable angina, and stable angina, respectively, and group 4 (100 healthy controls). Cytokine levels (interleukin-6, interleukin-8, interleukin-10, and tumor necrosis factor-alpha) were estimated by enzyme-linked immunosorbent assay (ELISA). Interleukin-6, interleukin-8, and tumor necrosis factor-alpha levels were significantly higher in patients from groups 1 and 2, than in group 3 and controls. Acute myocardial infarction patients exhibited higher serum levels of interleukin-10 compared with other groups and control subjects. Patients with unstable angina had significantly lower interleukin-10 concentrations than those with stable angina. The ratios of pro-/anti-inflammatory cytokines in all the study groups increased significantly when patients with unstable angina were compared to other groups. In patients with acute myocardial infarction, interleukin-10 and tumor necrosis factor-alpha levels showed significant correlation with established risk factors such as body mass index, blood pressure, and lipid levels. Acute myocardial infarction patients show elevation in proinflammatory and anti-inflammatory cytokines, while unstable angina is associated with low levels of serum interleukin-10. Higher levels of anti-inflammatory cytokine interleukin-10 may be needed to provide protection in unstable angina. These cytokines are markers of coronary artery disease and may be used for the identification of high-risk patients with unstable angina/acute myocardial infarction.

Effects of insulin resistance on endothelial function: possible mechanisms and clinical implications

Insulin resistance (IR) is defined as a reduced responsiveness of peripheral tissues to the effects of the hormone, referring to abated ability of insulin in stimulating glucose uptake in peripheral tissues and in inhibiting hepatic glucose output. Insulin has both a vasodilatory effect, which is largely endothelium dependent through the release of nitric oxide, and a vasoconstrictory effect through the stimulation of the sympathetic nervous system and the release of endothelin-1. IR and endothelial dysfunction (ED) are not only linked by common pathogenetic mechanisms, involving deranged insulin signalling pathways, but also by other, indirect to the hormone's actions, mechanisms. Different treatment modalities have been proposed to affect positively both the metabolic effects of insulin and ED. Weight loss has been shown to improve sensitivity to insulin as a result of either altered diet or exercise. Exercise has favourable effects on endothelial function in normal states and in states of disease, in men and women, and throughout the age spectrum and, hence, in IR states. Metformin improves sensitivity to insulin and most likely affects positively ED. Studies have shown that inhibitors of the renin-angiotensin system alter IR favourably, while Angiotensin converting enzyme (ACE) inhibitors and Angiotensin receptor type II (ATII) inhibitors improve ED. Ongoing studies are expected to shed more light on the issue of whether treatment with the thiazolidinediones results in improvement of endothelial function, along with the accepted function of improving insulin sensitivity. Finally, improved endothelial function by such treatments is not in itself proof of reduced risk for atherosclerosis; this remains to be directly tested in clinical trials.

Cardiovascular disease and heritability of the prothrombotic state

Atherothrombotic disease remains a major cause of mortality worldwide, and family clustering suggests an important contribution of genetic factors to disease pathogenesis. Thrombus formation represents the final step in atherothrombosis, a process influenced by genetic and environmental factors. A major difficulty of investigating the genetic regulation of thrombotic conditions is the complexity of the phenotype and the relatively modest effects of individual genetic variations. We address in this review genetic aspects involved in regulating thrombosis potential and their impact on the development of atherothrombotic disease. The effects of common genetic polymorphisms in clotting factors are discussed and examples of complex gene-gene and gene-environment interactions are highlighted. Understanding the effects of genetic factors on predisposition to thrombotic disease and unravelling the complex gene-environment interactions will help to better understand the pathophysiology of this complex condition, which will enable the development of new preventative and treatment strategies.

Increased plasma and optic nerve levels of IL-6, TNF-alpha, and MIP-2 following induction of ischemic optic neuropathy in mice

PURPOSE

To investigate levels of proinflammatory cytokines in a mouse model of anterior ischemic optic neuropathy (rAION).

METHODS

AION was induced in C57/BL6 mice and levels of IL-6, TNF-alpha, and MIP-2 were measured in plasma by ELISA and in the optic nerves by RT-PCR at predetermined intervals.

RESULTS

Plasma: IL-6 levels were elevated immediately after rAION induction and decreased gradually thereafter. TNF-alpha showed an early peak on day 1 and again from day 21. MIP-2 levels were increased until day 7. Optic nerve: IL-6, TNF-alpha, and MIP-2 levels increased within a few hours and then decreased gradually. IL-6 had a second peak on day 3.

CONCLUSIONS

Proinflammatory cytokines may play a role in the pathogenesis of rAION.

Severity of periodontal disease correlates to inflammatory systemic status and independently predicts the presence and angiographic extent of stable coronary artery disease

BACKGROUND

Periodontal disease (PD) has been recognized as a risk factor for systemic diseases, but its involvement in the pathogenesis of coronary artery disease (CAD) remains debated.

OBJECTIVES

We sought to evaluate the potential relations between severity of the PD, inflammatory response and angiographic lesions extent in patients with stable CAD.

DESIGN

A total of 131 subjects referred to our centre for coronary angiography were evaluated for presence and extension of CAD, then divided into two groups, one with presence of lesions (cases, n = 85) and other one with absence of lesions (controls, n = 46). Mean periodontal pocket depth (PPkD), high sensitivity C reactive protein (hs-CRP), serum amyloid A protein (SAA) and fibrinogen levels were measured in all patients.

RESULTS

Cases and controls did not differ according to their baseline characteristics and prevalence of traditional cardiovascular risk factors. PPkD was greater in patients with CAD than in controls (2.24 +/- 1.28 mm vs 1.50 +/- 0.93 mm, P < 0.001 by Student's t-test). Systemic inflammatory response was more pronounced in cases than in controls, with higher values of hs-CRP, SAA and fibrinogen. Furthermore, PPkD values correlated with hs-CRP (r = 0.80, P < 0.001), SAA (r = 0.71, P < 0.001), fibrinogen levels (r = 0.72, P < 0.001) and the American College of Cardiology/American Heart Association angiographic score (r = 0.68, P < 0.001) in cases. Multivariate analysis indicated a persistent independent correlation between PPkD and angiographic score after adjustment for inflammatory markers levels.

CONCLUSION

In the present study, PD lesions predicted presence of CAD stenosis in patients with cardiovascular risk factors. PD severity was correlated to angiographic extent of coronary lesions, independent of systemic inflammatory status. Those results suggest that these patients might benefit from an intensive periodontal therapy to prevent CAD progression.

Protein adsorption during LDL-apheresis: proteomic analysis

BACKGROUND

The aim of our study was to investigate the clearance of functional proteins by different low-density lipoprotein-apheresis (LDL-A) methods with the help of proteomic analyses.

METHODS

Proteins were eluated from the different LDL-A columns and investigated with 2D electrophoresis combined with mass spectrometry methods. In parallel, we quantified the plasma protein loss from patients treated with double-filtration plasmapheresis (DFPP; n = 9), direct adsorption of lipoproteins (DALI; n = 5) or heparin-induced extracorporeal LDL precipitation (HELP; n = 7) with routine laboratory methods and western blots.

RESULTS

Proteomic analyses of the column-bound proteins revealed a column-type-dependent loss with the highest number of protein spots in DALI-treated patients (1001 +/- 36), followed by HELP (881 +/- 25) and DFPP (535 +/- 20). More than 70 functional proteins were identified. These proteins are involved in the coagulation pathway (e.g. kininogen1) and have adhesive (e.g. fibronectin), rheological (e.g. fibrinogen) and immunological/inflammatory properties (e.g. complement components). Quantification with western blot analyses demonstrated a significant depletion (P < 0.01) of these proteins comparing serum samples before and after the column with a systemic lowering in patients' serum.

CONCLUSIONS

These data reveal strong interaction between column and serum proteins during LDL-A. The clearance of proteins with adhesive, rheological, and inflammatory characteristics may have beneficial effects on microcirculation and reduce chronic inflammation but may also concomitantly induce side effects such as an increased bleeding risk.

A systematic review and meta-analyses on C-reactive protein in relation to periodontitis

AIM

Elevated plasma C-reactive protein (CRP) is regarded as a risk predictor for cardiovascular diseases. This systematic review explored the robustness of observations that CRP is elevated in periodontitis. Similarly, the effect of periodontal therapy on CRP levels was investigated.

MATERIAL AND METHODS

Selection of publications was based on: (1) cross-sectional (case-control) studies; (2) longitudinal (treatment) studies; (3) high-sensitivity CRP measurement; (4) median and/or mean (+/-SD) values presented; and (5) subjects with no systemic disorders.

RESULTS

Screening of the initially 448 identified studies and reference checking resulted in 18 suitable papers. The majority of the studies showed that CRP levels are higher in patients than in controls. Often, studies showed that patients had CRP levels >2.1 mg/l. A meta-analysis of 10 cross-sectional studies showed that the weighted mean difference (WMD) of CRP between patients and controls was 1.56 mg/l (p<0.00001). Evidence from available treatment studies (n=6) showed lower levels of CRP after periodontal therapy. Eligible treatment studies in a meta-analysis demonstrated a WMD of reductions of CRP after therapy of 0.50 mg/L (95% CI 0.08-0.93) (p=0.02).

CONCLUSIONS

There is strong evidence from cross-sectional studies that plasma CRP in periodontitis is elevated compared with controls. There is modest evidence on the effect of periodontal therapy in lowering the levels of CRP.

Hemodynamic regulation of inflammation at the endothelial-neutrophil interface

Arterial shear stress can regulate endothelial phenotype. The potential for anti-inflammatory effects of shear stress on TNFalpha-activated endothelium was tested in assays of cytokine expression and neutrophil adhesion. In cultured human aortic endothelial cells (HAEC), arterial shear stress of 10 dyne/cm(2) blocked by >80% the induction by 5 ng/mL TNFalpha of interleukin-8 (IL-8) and IL-6 secretion (50 and 90% reduction, respectively, in the presence of nitric oxide synthase antagonism with 200 microM nitro-L-arginine methylester, L-NAME). Exposure of TNFalpha-stimulated HAEC to arterial shear stress for 5 h also reduced by 60% (p < 0.001) the conversion of neutrophil rolling to firm arrest in a venous flow assay conducted at 1 dyne/cm(2). Also, neutrophil rolling lengths at 1 dyne/cm(2) were longer when TNFalpha-stimulated HAEC were presheared for 5 h at arterial stresses. In experiments with a synthetic promoter that provides luciferase induction to detect cis interactions of glucocorticoid receptor (GR) and NFkappaB, shear stress caused a marked 40-fold induction of luciferase in TNFalpha-treated cells, suggesting a role for GR pathways in the anti-inflammatory actions of fluid shear stress. Hemodynamic force exerts anti-inflammatory effects on cytokine-activated endothelium by attenuation of cytokine expression and neutrophil firm arrest.

Common community infections and the risk for coronary artery disease and acute myocardial infarction: evidence for chronic over-expression of tumor necrosis factor alpha and vascular cells adhesion molecule-1

BACKGROUND

Although several common community infections have been associated with the risk for coronary artery disease (CAD), their role in the development of acute myocardial infarction (AMI) is still unclear. We examined the prevalence of IgG and IgM (or IgA) antibodies against common infections such as HSV, Hepatitis A (HAV), Helicobacter pylori (HP), cytomegalovirus (CMV) and Chlamydia pneumoniae (CP), in CAD and AMI patients, and their relationship with pro-atherogenic inflammatory molecules.

METHODS

A total number of 337 subjects were included in this study: 150 patients with angiographically documented stable CAD, 138 patients admitted with AMI and 49 healthy individuals. Serum IgG and IgM against HAV, CMV and HSV, IgG against HP and IgG/IgA against CP were determined in all participants. Serum tumor necrosis factor alpha (TNF-alpha) and soluble vascular cells adhesion molecule (sVCAM-1), were determined by ELISA.

RESULTS

Patients with CAD were more likely to have anti-HAV IgG (94.4%), anti-HSV IgG (97.2%) and anti-HP IgG (55.1%) compared to healthy individuals (70.8%, 89.6% and 39.6% respectively, p<0.05 for all). In multivariate analysis, anti-HAV IgG was an independent predictor of CAD (beta(SE): 0.187(0.075), p=0.015). Among the CAD patients, the presence of anti-CP IgA was more frequent in those admitted with AMI (39%) compared to those with stable CAD (21%, p<0.05). Finally, both patients and controls had significantly higher levels of sVCAM-1 and TNF-alpha in the presence of anti-HAV IgG, compared to those without anti-HAV IgG (p<0.05 for all).

CONCLUSION

Past infections with HAV, HSV and HP are associated with higher risk for coronary atherosclerosis, while the presence of anti-HAV IgG is also associated with higher levels of TNF-alpha and sVCAM-1. Furthermore, the presence of recent infection by CP is associated with higher risk for AMI among CAD patients. These findings are important since they demonstrate that past HAV, HSV and HP infections may affect cardiovascular risk, while recent CP infection may be implicated in the triggering of AMI among CAD patients.

Tumor necrosis factor alpha and adalimumab differentially regulate CD36 expression in human monocytes

In chronic inflammatory diseases, such as rheumatoid arthritis, inflammation acts as an independent cardiovascular risk factor and the use of anti-inflammatory drugs, such as anti-tumor necrosis factor alpha (anti-TNFα), may decrease this risk. The phagocytosis of oxidized low density lipoproteins (LDLs) accumulated in the subendothelium by mononuclear cells influences atherosclerosis and depends on CD36 expression. We investigated the role of TNFα and adalimumab, a human anti-TNFα monoclonal antibody widely used in human pathology, in CD36 expression in human monocytes. Human monocytes were prepared by adherence from whole-blood buffy-coat fractions from healthy donors. CD36 expression was assessed by RT-PCR and flow cytometry, with various TNFα or adalimumab concentrations. Implication of peroxisome proliferator-activated receptor (PPAR)γ in the regulation of CD36 expression was assessed using specific inhibitor or gel shift assays. The impact of redox signaling was investigated using quantification of reactive oxygen species, antioxidant and a NADPH oxidase inhibitor. The F(ab')2 fragment of adalimumab was isolated and its effect was analyzed. TNFα inhibits both CD36 membrane expression and mRNA expression. This inhibition involves a reduction in PPARγ activation. In contrast, adalimumab increases both CD36 membrane expression and mRNA expression. This induction is independent of the Fc portion of adalimumab and involves redox signaling via NADPH oxidase activation. CD36 expression on human monocytes is inhibited by TNFα and independently increased by adalimumab. These data highlight that pro-inflammatory cytokines and their specific neutralization influence the expression of cellular receptors implicated in atherosclerosis. Further studies are needed to investigate the clinical implications of these results in accelerated atherosclerosis observed in rheumatoid arthritis.

Periodontitis may increase the risk of peripheral arterial disease

OBJECTIVES

The aim of this case control study was to evaluate whether periodontitis was associated with peripheral arterial disease (PAD).

SUBJECTS AND METHODS

Twenty-five patients diagnosed with aorto-iliac and/or femoro-popliteal occlusive disease and thirty-two generally healthy control subjects were enrolled in this study. Polymerase chain reaction (PCR) was used to identify Porphyromonas gingivalis, Treponema denticola, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Cytomegalovirus (CMV), Chlamydia pneumoniae, and Helicobacter pylori in tissue specimens taken from the anastomotic site of distal bypasses. Periodontal status was evaluated; serum IgG titres against the four listed bacteria were measured.

RESULTS

Periodontopathic bacteria were detected in 13/25 (52%) atherosclerotic specimens. CMV or C. pneumoniae was detected in 1/25 (4%) specimens; H. pylori was not detected from any of these specimens. Fontaine grade III or IV patients showed higher detection frequency of P. gingivalis than Fontaine grade II patients (57.1% vs 22.2%, P=0.09). After adjusting for age, gender, diabetes and smoking, periodontitis increased 5-fold the risk of having PAD (OR 5.45). There were preliminary indications that periodontitis was associated with increased serum IL-6 and TNF-alpha concentrations.

CONCLUSIONS

This study suggests that periodontitis may be associated with an increased risk of PAD. This association could result from the increased concentration of serum inflammatory cytokines in those with periodontitis.

Chemokines and left ventricular function in patients with acute myocardial infarction

BACKGROUND

Leukocytes are activated in the inflammatory process involving locally atherosclerotic lesions through adhesive molecules attaching to the surface of endothelial cells, especially during acute myocardial infarction. The aim of the study was to assess MCP-1, MIP-1alpha, and RANTES serum levels in patients with STEMI and to correlate them with the severity of left ventricle (LV) dysfunction.

METHODS

Forty patients were initially divided into two groups, with group 1 having an ejection fraction (EF) above 40% and group 2 an EF of 40% or less. Next, the patients were divided on the basis of wall motion score index (WMSI): group 3 had a WMSI of 1.3 or lower and group 4 had a WMSI above 1.3. A control group of ten volunteers was also included in the study. Serum samples were taken at admission as well as 3, 24, 48, 72 h, and 7 days after.

RESULTS

The baseline serum levels of MCP-1 and RANTES in group 1 were significantly higher than in the controls (p<0.05 and p<0.005, respectively). The highest concentrations of chemokines were observed 3 h after admission. The serum levels of MIP-1alpha on admission and 3 h later were significantly higher in group 1 than in group 2 (p<0.03 and p<0.01, respectively). Maximum MIP-1 concentrations were observed 3 h after admission in group 3 and 24 h after admission in group 4 (p<0.006). In group 1, MIP-1alpha 3 h after admission correlated positively with the EF (r=0.444, p<0.05). In group 1 there was a negative correlation between MIP-1alpha concentration 3 h after admission and LV end-diastolic dimension (r=-0.492, p<0.02).

CONCLUSIONS

Patients with myocardial infarction with an elevated ST segment had a significant increase in MCP-1, MIP-1alpha, and RANTES serum levels.

Effect of Pentoxifylline on inflammatory burden, oxidative stress and platelet aggregability in hypertensive type 2 diabetes mellitus patients

OBJECTIVES

Inflammation and oxidative stress are main culprits behind atherosclerosis in diabetes mellitus. This study explores the effect of add-on Pentoxifylline on inflammatory burden and oxidative stress in hypertensive diabetic patients.

RESEARCH DESIGN AND METHODS

60 hypertensive type 2 diabetic, aged > or = 45 years were evaluated for anthropometry, clinical parameters, C-reactive protein, total leukocyte count, erythrocyte sedimentation rate, serum albumin, plasma malondialdehyde, blood reduced glutathione, platelet aggregation and clot retraction profile. With informed consent and randomization, Pentoxifylline (400 mg) was prescribed to 30 patients orally twice daily with meals as add-on therapy to the standard therapeutic regimen for one month. The particular parameters were repeated in 26 patients in control group and 25 patients in Pentoxifylline group who completed the follow up. The study was a randomized, open, add-on clinical trial with parallel controls.

RESULTS

At one-month follow-up, in the Pentoxifylline group, there was 20.9% decrease (p<0.001) in C-reactive protein, 18% reduction (p<0.001) in erythrocyte sedimentation rate, 11.1% reduction (p<0.001) in total leukocyte count and 5.8% increase (p=0.003) in serum albumin. Pentoxifylline showed 20.2% reduction in plasma malondialdehyde and 4.6% increase in blood reduced glutathione level. In therapeutic dose range, Pentoxifylline exerted a significant anti-aggregatory effect and a dose dependent decrease in clot retraction in-vitro but there was no significant change in ex-vivo clot retraction. The control group showed no statistically significant change in parameters assessed.

CONCLUSION

This study reveals improvements in inflammatory markers, oxidative stress and platelet-aggregation by Pentoxifylline, thus preventing atherosclerosis in diabetes mellitus.

Pathology of inflammatory native valvular heart disease

Rheumatic disease is an important cause of inflammatory native heart valve disease. However, with increased understanding of the pathoetiology of valve disease and valve injury, it is evident that inflammation may play a role in many valve disorders. We are only beginning to understand these complex processes. With increasing knowledge that many of these processes are active, there may be opportunity for intervention or even prevention.

Coagulation and atherothrombotic disease

Atherothrombotic disease arises secondary to a complex gene-environment interaction. In the initial stages, the condition is clinically silent but with more advanced disease, an occlusive thrombus is formed resulting in the classical clinical manifestations. Both environmental factors and genetic variations in elements of the clotting cascade influence thrombosis risk by inducing quantitative and qualitative changes in the mature protein, which may affect the final structure of the clot and determine its resistance to lysis. Understanding the fine details of gene-environment interactions in relation to thrombus formation will help to shed more light on disease pathogenesis. Consequently, this will allow the development of more efficacious treatment strategies and will also help to identify subjects at risk, thereby enabling the introduction of early preventative measures.

Increased high sensitivity C-reactive protein and neutrophil count are related to increased standard cardiovascular risk factors in healthy Chinese men

BACKGROUND

Epidemiologic data regarding the role of inflammation in atherosclerosis have been based mainly on Caucasian populations. Thus, we analyzed the cross-sectional relationships of inflammatory biomarkers to cardiovascular risk factors (CVRF) and related variables in a large group of healthy Chinese men, a population with a markedly lower heart disease mortality rate compared with Western populations.

METHODS

The study consisted of 8374 men aged 20-80 who attended a voluntary health examination at a metropolitan university center between 1997 and 2002. The relationships between serum high sensitivity C-reactive protein (hsCRP), total white blood cell (WBC), neutrophil, and monocyte counts to CVRF were analyzed using multivariate linear and logistic regression analyses. Whether a dose-response effect existed between elevated levels of each marker and increasing numbers of CVRF was also evaluated.

RESULTS

The distribution of hsCRP was similar to Western studies. Both multivariate regression analyses showed all four markers to have significant correlations with body mass index, triglycerides, and adverse high density lipoprotein/low density lipoprotein ratio. Smoking was associated with increased levels of all four markers. Elevated neutrophil count had the most markedly progressive dose-response effect with increasing numbers of CVRF, whereas elevated monocyte count showed a drop in risk with CVRF of five and above.

CONCLUSION

We show in our study that with increasing numbers of standard CVRF, healthy Chinese men have progressive and increasing risks of having elevated levels of hsCRP, total WBC, and neutrophil counts. While the inflammatory markers surveyed were largely correlated with CVRF, the similar values of CRP between populations with divergent mortality rates suggest that a more complex relationship may exist between CRP and disease outcome. The possible utility of neutrophil count as a marker for cardiovascular disease risk in healthy men awaits further evaluation in prospective studies.

Effects of cinnamic acid on expression of tissue factor induced by TNFalpha in endothelial cells and its mechanisms

BACKGROUND

To observe the effects of cinnamic acid (CINN) on the expression of tissue factor (TF) induced by tumor necrosis factor alpha (TNFalpha) in human umbilical vein endothelium-derived cell line (ECV304) and the related mechanisms.

METHODS

Cellular TF activity was determined with 1-stage clotting assay in the presence or absence of anti-TF antibody or DEGR-Vlla. TF mRNA was examined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). I-kappaB was measured by Western blot analysis. Immunohistochemical analysis was performed to evaluate the activation of NF-kappaB.

RESULTS

CINN (500 microg/mL) significantly decreased the TF activity in ECV304 induced by TNFalpha (1000 U/mL) (p < 0.01) in a concentration-dependent fashion (r = -0.953, p < 0.05). CINN also inhibited the expression of TF mRNA induced by TNFalpha. Immunohistochemical analysis demonstrated NF-kappaB translocation from the cytoplasm to the nucleus, and Western blot analysis showed I-KB decrement in cytoplasm after treatment of endothelial cells with TNFalpha. CINN diminished these changes induced by TNFalpha.

CONCLUSION

CINN is able to attenuate TNFa-induced TF expression of vascular endothelial cells by inhibiting NF-kappaB activation.

Systemic markers of inflammation in periodontitis

This literature review summarizes current knowledge on the systemic levels of selected markers of inflammation in periodontitis. From samples of peripheral blood the following cellular factors are discussed: total number of white blood cells, red blood cells, and thrombocytes. Further, plasma levels of acute-phase proteins, cytokines, and coagulation factors are reviewed. From the available literature it appears that the total numbers of leukocytes and plasma levels of C-reactive protein are consistently higher in periodontitis patients compared to healthy controls. Numbers of red blood cells and levels of hemoglobin are lower in periodontitis and there is a trend towards anemia of chronic disease. Most systemic markers of inflammation discussed in this review are also regarded as predictive markers for cardiovascular diseases. Therefore, changes in these markers in periodontitis may be part of the explanation why periodontitis is associated with cardiovascular diseases and/or cerebrovascular events in epidemiological studies. It is hypothesized that possibly daily episodes of a bacteremia originating from periodontal lesions are the cause for the changes in systemic markers in periodontitis; the cumulative size of all periodontal lesions in the untreated severe patient may amount to 15 to 20 cm2.

Platelets in atherothrombosis

Atherosclerosis is a diffuse, systemic disease that affects the coronary, cerebral, and peripheral arterial trees. Disruption of atherosclerotic plaques leads to thrombus formation and arterial occlusion. This unpredictable and potentially life-threatening atherothrombotic sequence underlies clinical events such as angina, myocardial infarction, transient ischemic attacks, and stroke. One of the key components of a clot is the platelet. Although it was previously thought that platelets were relatively inactive cells that merely provided a framework for the attachment of other cells and proteins to mechanically stop bleeding due to injury, it is now known that this is not the case. Platelets secrete and express a large number of substances that are crucial mediators of both coagulation and inflammation. This article reviews the centrality of the platelet in atherothrombosis and briefly looks at the efficacy of antiplatelet agents in preventing and treating cardiovascular disease.

Association between Neopterin and Carotid Intima-Media Thickness in Hemodialysis Patients

BACKGROUND

Atherosclerotic lesions are heavily infiltrated by macrophages. Neopterin can be used as a marker of the activity of macrophages. Serum neopterin levels were elevated in non-renal patients with atherosclerosis. The intima-media thickness (IMT) of the carotid arteries in hemodialysis patients was significantly higher than in control subjects. In this study, we measured serum neopterin levels in hemodialysis patients and evaluated a possible correlation between neopterin levels and carotid IMT.

PATIENTS AND METHODS

Thirty-seven hemodialysis patients (26 male/11 female, mean age 47 +/- 15 years) and 12 healthy subjects (8 male/4 female, mean age 43 +/- 10 years) were included in this study. Serum neopterin levels were measured by using a commercial ELISA kit. Carotid IMT of the subjects were measured by high-resolution B-mode ultrasonography.

RESULTS

Carotid IMT values were 1.04 +/- 0.29 and 0.77 +/- 0.25 mm in hemodialysis patients and healthy controls, respectively (p < 0.01). Serum neopterin levels were 110.9 +/- 19.1 and 3.8 +/- 2.3 ng/ml in hemodialysis patients and healthy controls, respectively (p < 0.01). Serum neopterin levels were 103.2 +/- 21.3 ng/ml in hemodialysis patients with IMT < 1 mm (n = 15), and 116.7 +/- 15.4 ng/ml in hemodialysis patients with IMT > or = 1 mm (n = 22) (p < 0.05). Moreover, there was a significant correlation between serum neopterin levels and carotid IMT (p < 0.05, r = 0.363).

CONCLUSION

Our findings suggest that neopterin could be associated with the severity of carotid atherosclerosis in hemodialysis patients.

Elevated white cell count at commencement of peritoneal dialysis predicts overall and cardiac mortality

BACKGROUND

Higher total white blood cell counts (WCC) have been shown in the general population to be strongly and independently predictive of coronary heart disease and all-cause mortality. The aim of the present study was to evaluate the prognostic value of WCC in patients commencing peritoneal dialysis (PD).

METHODS

A cohort of 323 patients (mean age 55.1 +/- 17.7 years, 54% male, 81% Caucasian) commencing PD at the Princess Alexandra Hospital between January 1, 1998 and March 31, 2003 were prospectively followed until death, completion of PD therapy, or otherwise to the end of the study (January 2, 2004), at which point data were censored. Individuals with failed renal transplants (N= 17) and those with acute infections at the time of PD onset (N= 12) were not included. A multivariate Cox's proportional hazards model was applied to calculate hazard ratios and adjusted survival curves for time to death or cardiac death, adjusting for baseline demographic, clinical, and laboratory characteristics.

RESULTS

Median actuarial patient survival was 3.9 years [95% confidence interval (CI) 3.2-4.7 years]. The highest quartile of WCC (>9.4 x 10(9)/L) was significantly and independently associated with increased risks of both death from all causes [adjusted hazard ratio (HR) 2.27, 95% CI 1.09-4.74, P < 0.05] and cardiac death (HR 3.75, 95% CI 1.2-11.8, P < 0.05). Other adverse risk factors included older age, lower serum albumin, and the presence of coronary artery disease. Similar associations were found between mortality and PMN count, but not lymphocyte count.

CONCLUSION

Elevated baseline WCC or PMN count at the commencement of PD (in the absence of acute infection) strongly predicts all-cause and cardiovascular mortality. These data suggest that new PD patients with higher WCC may warrant closer monitoring and extra attention to modifiable cardiovascular risk factors.

Role of cytokines in cardiovascular diseases: a focus on endothelial responses to inflammation

Complex cellular and inflammatory interactions are involved in the progress of vascular diseases. Endothelial cells, upon exposure to cytokines, undergo profound alterations of function that involve gene expression and de novo protein synthesis. The functional reprogramming of endothelial cells by cytokines is of importance especially in patients with chronic vascular inflammation. The intercellular network of dendritic cells, T-lymphocytes, macrophages and smooth muscle cells generates a variety of stimulatory cytokines [e.g. TNF-alpha (tumour necrosis factor-alpha), IL (interleukin)-1, IL-6 and IFN-gamma (interferon-gamma)] and growth factors that promote the development of functional and structural vascular changes. High concentrations of proinflammatory cytokines increase oxidative stress, down-regulate eNOS (endothelial nitric oxide synthase) bioactivity and induce endothelial cell apoptosis. Chemoattractant cytokines [e.g. VEGF (vascular endothelial growth factor), TGF-beta1 (transforming growth factor-beta1) and IL-8] are important regulators of inflammation-induced angiogenesis and are directly modulated by nitric oxide. This review will focus on the vascular mechanisms orchestrated by cytokines and summarizes the current knowledge concerning the contribution of cytokines to cardiovascular diseases.

Exposure to welding fumes is associated with acute systemic inflammatory responses

AIMS

To investigate the acute systemic inflammatory response to welding fume exposure.

METHODS

Twenty four welders (42% smokers) and 13 non-exposed controls (23% smokers) were monitored at a welding school. Exposure to fine particulate matter (PM2.5) was assessed using cyclone samplers. Markers of systemic inflammation, including C-reactive protein (CRP), fibrinogen, and white blood cell (WBC) levels, were determined in peripheral blood samples collected at baseline and after 5.3 (SD 1.0) hours of exposure.

RESULTS

The median PM2.5 concentration for welders was 1.66 mg/m3, which was significantly greater than that for controls (0.04 mg/m3). Compared to non-smokers, smokers had a significantly higher baseline WBC count, but comparable levels of CRP and fibrinogen. In non-smokers, welding fume exposure was associated with a significant increase in WBC and neutrophil counts immediately following exposure (+0.8x10(3)/mul, 95% CI 0.1 to 1.6, and +1.0x10(3)/mul, 95% CI 0.4 to 1.7, respectively). A significant decrease in fibrinogen levels was observed in non-smokers (-32 mg/dl, 95% CI -63 to -1). No significant changes in WBC, neutrophil, and fibrinogen levels were found in smokers. Sixteen hours after welding exposure, CRP levels were found to be significantly increased in both non-smokers and smokers (0.90 mg/l, 95% CI 0.17 to 1.64). PM2.5 concentrations were found to be significantly associated with absolute neutrophil counts in non-smokers, and CRP levels in both non-smokers and smokers.

CONCLUSIONS

High levels of welding fume exposure induce acute systemic inflammation in a relatively young, healthy working population. These results also suggest that smoking may modify the effect of welding fume exposure on specific inflammatory markers.

A Pilot Study Into Measurements of Markers of Atherosclerosis in Periodontitis

BACKGROUND

Periodontitis may be a possible risk factor for atherosclerosis. The current pilot study explored arterial wall thickness and other variables associated with atherosclerosis in healthy subjects with and without periodontitis.

METHODS

Patients with moderate (N = 34) and severe periodontitis (N = 15) and controls (N = 14) were recruited. Intima media thickness (IMT) of the common carotid arteries (CCA), internal carotid arteries (ICA), and bifurcations of carotid arteries (BCA) was estimated bilaterally using B-mode ultrasound. An overall IMT was calculated as the mean of these six measurements. C reactive protein (CRP), fibrinogen, and von Willebrand factor (vWf) were measured in plasma as indicators of systemic inflammation and atherosclerotic disease. Microalbuminuria was determined as a marker of endothelial cell dysfunction.

RESULTS

IMT for CCA were 0.64, 0.68, and 0.69 mm for control, moderate, and severe periodontitis, respectively (not significant). IMT for BCA did not vary among groups. IMT of ICA was largest for severe periodontitis (0.81 mm); corresponding values for controls and moderate periodontitis were 0.58 and 0.55 mm, respectively (P= 0.023). Severe periodontitis patients had an overall IMT of 0.76 mm, while moderate periodontitis patients and controls had lower values (0.64 and 0.65 mm, respectively; P= 0.153). After adjusting for potential confounding factors, the increased IMT for ICA in severe periodontitis was also significant (Padj = 0.040). CRP (P= 0.020, Padj = 0.050) and vWf (P= 0.019, Padj = 0.013) were higher in periodontitis than controls; microalbuminuria was not different between groups. Power calculations suggest that a 4-fold expansion of the severe patient and control groups will result in a high chance (power level 80%) that a clinically significant association between the overall IMT and periodontitis will be observed.

CONCLUSION

The present pilot study indicates that a full study investigating the relationship between periodontitis and atherosclerosis is warranted.

Elevated plasma levels of interleukin 8 in patients with acute anterior ischaemic optic neuropathy

BACKGROUND/AIM

Alterations of the immune system may have a role in thrombogenesis. Artery sites occluded with thrombi apparently release pro-inflammatory cytokines. Non-arteritic anterior ischaemic optic neuropathy (NAION) results from occlusion of the blood supply to the optic nerve. The aim of this study was to analyse levels of pro-inflammatory cytokines in patients with acute event of NAION.

METHODS

Study participants included 10 patients (12 eyes) with NAION and 20 age matched controls with the same risk factors for atherosclerosis disease. Peripheral blood samples were obtained immediately at the acute onset of NAION. Plasma interleukin 8 (IL-8), IL-6, and tumour necrosis factor alpha (TNF-alpha) levels were measured immediately following diagnosis and during the follow up intervals.

RESULTS

The plasma levels of IL-8 were significantly higher in NAION patients at the time of diagnosis in comparison to the control group (p = 0.002), and decreased during the follow up period (6-12 months) (p = 0.05). There were no differences in plasma levels of IL-6 and TNF-alpha between NAION patients and controls, either in the acute phase or during the follow up period.

CONCLUSION

Plasma levels of IL-8 are elevated during the acute phase of NAION, but not IL-6 and TNF-alpha. These elevated levels are in accordance with other acute vascular thrombosis. The clinical significance of these findings should be further evaluated.

Effects of inflammatory cytokines on the release and cleavage of the endothelial cell-derived ultralarge von Willebrand factor multimers under flow

ADAMTS13 cleaves ultralarge and hyperreactive von Willebrand factor (ULVWF) freshly released from activated endothelial cells to smaller and less active forms. This process may be affected by the amount of ULVWF released and the processing capacity of ADAMTS13, contributing to the development of thrombotic diseases. We examined the effects of inflammatory cytokines on the release and cleavage of ULVWF to evaluate potential links between inflammation and thrombosis. Human umbilical vein endothelial cells were treated with interleukin 6 (IL-6), IL-8, or tumor necrosis factor alpha (TNF-alpha), and the formation of platelet-decorated ULVWF strings was quantitated. IL-8 and TNF-alpha significantly stimulated the release of ULVWF in a dose-dependent manner. IL-6 induced ULVWF release only when it was in complex with the soluble IL-6 receptor. IL-6, but not IL-8 nor TNF-alpha, inhibited the cleavage of ULVWF strings by ADAMTS13 under flowing, but not static, conditions. These results suggest that inflammatory cytokines may stimulate the ULVWF release (IL-8 and TNF-alpha) and inhibit the ULVWF cleavage (IL-6), resulting in the accumulation of hyperreactive ULVWF in plasma and on the surface of endothelial cells to induce platelet aggregation and adhesion on the vascular endothelium. The findings describe a potential linkage between inflammation and thrombosis that may be of therapeutic importance.