Tumor necrosis factor receptor levels are associated with carotid atherosclerosis

Evaluating thrombosis risk and patient-specific treatment strategy using an atherothrombosis-on-chip model

Platelets play an essential role in thrombotic processes. Recent studies suggest a direct link between increased plasma glucose, lipids, and inflammatory cytokines with platelet activation and aggregation, resulting in an increased risk of atherothrombotic events in cardiovascular patients. Antiplatelet therapies are commonly used for the primary prevention of atherosclerosis. Transitioning from a population-based strategy to patient-specific care requires a better understanding of the risks and advantages of antiplatelet therapy for individuals. This proof-of-concept study evaluates the potential to assess an individual's risk of forming atherothrombosis using a dual-channel microfluidic model emulating multiple atherogenic factors in vitro, including high glucose, high cholesterol, and inflammatory cytokines along with stenosis vessel geometry. The model shows precise sensitivity toward increased plasma glucose, cholesterol, and tumour necrosis factor-alpha (TNF-α)-treated groups in thrombus formation. An in vivo-like dose-dependent increment in platelet aggregation is observed in different treated groups, benefiting the evaluation of thrombosis risk in the individual condition. Moreover, the model could help decide the effective dosing of aspirin in multi-factorial complexities. In the high glucose-treated group, a 50 μM dose of aspirin could significantly reduce platelet aggregation, while a 100 μM dose of aspirin was required to reduce platelet aggregation in the glucose-TNF-α-treated group, which proves the model's potentiality as a tailored tool for customised therapy.

Glycyrrhizic Acid Inhibits High-Mobility Group Box-1 and Homocysteine-Induced Vascular Dysfunction

Hyperhomocysteinemia (HHcy) worsens cardiovascular outcomes by impairing vascular function and promoting chronic inflammation via release of danger-associated molecular patterns, such as high-mobility group box-1 (HMGB-1). Elevated levels of HMGB-1 have recently been reported in patients with HHcy. Therefore, targeting HMGB-1 may be a potential therapy to improve HHcy-induced cardiovascular pathologies. This study aimed to further elucidate HMGB-1's role during acute HHcy and HHcy-induced atherogenesis and to determine if inhibiting HMGB-1 with glycyrrhizic acid (Glyz) improved vascular function. Male New Zealand White rabbits (n = 25) were placed on either a standard control chow (CD; n = 15) or atherogenic diet (AD; n = 10) for 4 weeks. Rabbit serum and Krebs taken from organ bath studies were collected to quantify HMGB-1 levels. Isometric tension analysis was performed on abdominal aorta (AA) rings from CD and AD rabbits. Rings were incubated with homocysteine (Hcy) [3 mM] for 60 min to induce acute HHcy or rhHMGB-1 [100 nM]. Vascular function was assessed by relaxation to cumulative doses of acetylcholine. Markers of vascular dysfunction and inflammation were quantified in the endothelium, media, and adventitia of AA rings. HMGB-1 was significantly upregulated in serum (p < 0.0001) and Krebs (p < 0.0001) after Hcy exposure or an AD. Incubation with Hcy (p < 0.0001) or rhHMGB-1 (p < 0.0001) and an AD (p < 0.0001) significantly reduced relaxation to acetylcholine, which was markedly improved by Glyz. HMGB-1 expression was elevated (p < 0.0001) after Hcy exposure and AD (p < 0.0001) and was normalized after Glyz treatment. Moreover, markers of vascular function, cell stress and inflammation were also reduced after Glyz. These results demonstrate that HMGB-1 has a central role during HHcy-induced vascular dysfunction and inhibiting it with Glyz could be a potential treatment option for cardiovascular diseases.

Gender differences in fasting and postprandial metabolic traits predictive of subclinical atherosclerosis in an asymptomatic Chinese population

The prediction utility of Framingham Risk Score in populations with low conventional cardiovascular risk burden is limited, particularly among women. Gender-specific markers to predict cardiovascular risk in overtly healthy people are lacking. In this study we hypothesize that postprandial responses triggered by a high-calorie meal test differ by gender in their ability to triage asymptomatic subjects into those with and without subclinical atherosclerosis. A total of 101 healthy Chinese subjects (46 females, 55 males) at low risk of coronary heart disease completed the study. Subjects underwent cardiovascular imaging and postprandial blood phenotyping after consuming a standardized macronutrient meal. Prediction models were developed using logistic regression and subsequently subjected to cross-validation to obtain a de-optimized receiver operating characteristic (ROC) curve. Distinctive gender differences in postprandial trajectories of glucose, lipids and inflammatory markers were observed. We used gender-specific association with different combinations of postprandial predictors to develop 2 models for predicting risk of subclinical atherosclerosis in males (ROC AUC = 0.7867, 95% CI 0.6567, 0.9166) and females (ROC AUC = 0.9161, 95% CI 0.8340, 0.9982) respectively. We report novel postprandial models for predicting subclinical atherosclerosis in apparently healthy Asian subjects using a gender-specific approach, complementing the conventional Framingham Risk Score.Clinical Trial Registration: The trial was registered at clinicaltrials.gov as NCT03531879.

Longitudinal Study Reveals Long-Term Proinflammatory Proteomic Signature After Ischemic Stroke Across Subtypes

Inflammation contributes both to the pathogenesis of stroke and the response to brain injury. We aimed to identify proteins reflecting the acute-phase response and proteins more likely to reflect proinflammatory processes present before stroke by broadly profiling inflammation-related plasma proteins in a longitudinal ischemic stroke study.

Myocardin-Related Transcription Factor A Mediates LPS-Induced iNOS Transactivation

Macrophage-dependent inflammation plays a critical role in atherogenesis. Inducible nitric oxide synthase (iNOS) is one of key pro-inflammatory mediators produced in macrophages and its levels can be upregulated by lipopolysaccharide (LPS). The epigenetic mechanism whereby LPS induces iNOS transcription is incompletely understood. We show here myocardin-related transcription factor A (MRTF-A) potentiated iNOS promoter activity in macrophages. There was a decrease in LPS-induced iNOS expression in several cell models due to the lack of MRTF-A. LPS treatment promoted nuclear accumulation of MRTF-A and its interaction with NF-κB/p65 on the iNOS promoter. The absence of MRTF-A prevented the accumulation of active histone marks on the iNOS promoter in response to LPS treatment. Mechanistically, MRTF-A recruited ASH2, a key component of the mammalian histone H3K4 methyltransferase complex, to the iNOS promoter. Silencing of ASH2 attenuated iNOS expression following LPS treatment. Together, our data highlight a role for MRTF-A-dependent recruitment of H3K4 methyltransferase in iNOS induction and as such provide a novel target in the intervention of atherosclerosis.

Regional Molecular Signature of the Symptomatic Atherosclerotic Carotid Plaque

BACKGROUND

Many studies have explored molecular markers of carotid plaque development and vulnerability to rupture, usually having examined whole carotid plaques. However, there are regional differences in plaque morphology and known shear-related mechanisms in areas surrounding the lipid core.

OBJECTIVE

To determine whether there are regional differences in protein expression along the long axis of the carotid plaque and how that might produce gaps in our understanding of the carotid plaque molecular signature.

METHODS

Levels of 7 inflammatory cytokines (IL-1β, IL-6, IL-8, IL-10, IL-12 p70, IFN-γ, and TNF-α) and caspase-3 were analyzed in prebifurcation, bifurcation, and postbifurcation segments of internal carotid plaques surgically removed from symptomatic and asymptomatic patients. Expression profiles of miRNAs and mRNAs were determined with microarrays for the rupture-prone postbifurcation segment for comparison with published whole plaque results.

RESULTS

Expression levels of all proteins examined, except IL-10, were lowest in the prebifurcation segment and significantly higher in the postbifurcation segment. Patient group differences in protein expression were observed for the prebifurcation segment; however, no significant differences were observed in the postbifurcation segment between symptomatic and asymptomatic patients. Expression profiles from postbifurcation carotid plaques identified 4 novel high priority miRNAs differentially expressed between patient groups (miR-214, miR-484, miR-942, and miR-1287) and 3 high-confidence miRNA:mRNA targets, including miR-214:APOD, miR-484:DACH1, and miR-942:GPR56.

CONCLUSION

The results demonstrate regional differences in protein expression for the first time and show that focus on the rupture-prone postbifurcation region leads to prioritization for further study of novel miRNA gene regulation mechanisms.

Distinct inflammatory mediator patterns in young black and white adults: The African-predict study

OBJECTIVE

Inflammatory mediators have been implicated in the early stages of cardiovascular disease development, including hypertension. Since global reports reflect a higher hypertension prevalence in black than white populations, we hypothesise the involvement of specific inflammatory mediators. We therefore compared a detailed range of 22 inflammatory mediators between young black and white adults, and determined the relationship with blood pressure.

APPROACH AND RESULTS

We included 1197 adults (20-30 years; 50% black; 52% female) with detailed ambulatory blood pressures. Blood samples were analysed for 22 inflammatory mediators. For pro-inflammatory mediators, the black adults had higher C-reactive protein, interferon-inducible T-cell alpha chemoattractant, macrophage inflammatory protein 3 alpha (all p ≤ 0.008), but lower interferon-gamma, interleukin (IL)-1β, IL-8, IL-12, IL-17A, and tumour necrosis factor alpha (all p ≤ 0.048). For anti-inflammatory mediators the black group consistently had lower levels (IL-5, IL-10 and IL-13 (all p ≤ 0.012)), resulting in generally higher pro-to-anti-inflammatory ratios in black than white adults (p ≤ 0.001). In mediators with pro- and anti-inflammatory functions, the black group had lower granulocyte-macrophage colony-stimulating factor and IL-6 (both p ≤ 0.010). These patterns were confirmed after adjustment for age, sex and waist circumference, or when stratifying by hypertensive status, sex and socio-economic status. Multi-variable adjusted regression analyses and factor analysis yielded no relationship between inflammatory mediators and blood pressure in this young healthy population.

CONCLUSIONS

Black and white ethnic groups each consistently presented with unique inflammatory mediator patterns regardless of blood pressure, sex or social class. No association with blood pressure was seen in either of the groups.

Targeting thrombogenicity and inflammation in chronic HIV infection

Persons with HIV infection (PWH) have increased risk for cardiovascular disease (CVD), but the underlying mechanisms remain unclear. Coronary thrombosis is known to provoke myocardial infarctions, but whether PWH have elevated thrombotic propensity is unknown. We compared thrombogenicity of PWH on antiretroviral therapy versus matched controls using the Badimon chamber. Measures of inflammation, platelet reactivity, and innate immune activation were simultaneously performed. Enrolled PWH were then randomized to placebo, aspirin (81 mg), or clopidogrel (75 mg) for 24 weeks to assess treatment effects on study parameters. Thrombogenicity was significantly higher in PWH and correlated strongly with plasma levels of D-dimer, soluble TNF receptors 1 and 2, and circulating classical and nonclassical monocytes in PWH. Clopidogrel significantly reduced thrombogenicity and sCD14. Our data suggest that higher thrombogenicity, interacting with inflammatory and immune activation markers, contributes to the increased CVD risk observed in PWH. Clopidogrel exhibits an anti-inflammatory activity in addition to its antithrombotic effect in PWH.

The concentration of tumor necrosis factor in the blood serum and in the urine and selected early organ damages in patients with primary systemic arterial hypertension

Arterial hypertension is considered to be an inflammatory condition with low intensity. Therefore, an elevated concentration of inflammatory cytokines can be expected in patients with systemic arterial hypertension, including tumor necrosis factor (TNF).The study included a group of 96 persons aged 18 to 65 years: 76 patients with primary arterial hypertension and 20 healthy individuals (control group). Blood pressure was measured in all individuals using the office and ambulatory blood pressure monitoring (ABPM) measurement, blood was collected for laboratory tests [tumor necrosis factor (TNF), tumor necrosis factor receptor 1 (TNFR1)], and 24-hour urine collection was performed in which albuminuria and TNF concentration were assessed. Moreover, assessment of the intima-media thickness (IMT) in ultrasonography and left ventricular mass index (LVMI) in echocardiography were carried out.Statistically elevated TNF concentration in the blood serum (P = .0001) and in the 24-hour urine collection (P = .0087) was determined in patients with hypertension in comparison with the control group. The TNF and TNFR1 concentration in the serum and TNF in the 24-hour urine in the group of patients with arterial hypertension and organ damages and without such complications did not differ statistically significantly.We observed a positive and statistically significant correlation between TNFR1 concentration in the serum and TNF urine excretion in patients with hypertension (r = 0.369, P < .05)Patients with arterial hypertension are characterized by higher TNF concentrations in blood serum and higher TNF excretion in 24-hour urine than healthy persons.TNF and TNFR1 concentration in blood serum and TNF excretion in 24-hour urine in patients with early organ damages due to arterial hypertension do not differ significantly from those parameters in patients with arterial hypertension without organ complications.There is a positive correlation between TNFR1 concentration in the serum and TNF urine excretion in patients with hypertension.

Perspectives on ethnic and racial disparities in Alzheimer's disease and related dementias: Update and areas of immediate need

Alzheimer's disease and related dementias (ADRDs) are a global crisis facing the aging population and society as a whole. With the numbers of people with ADRDs predicted to rise dramatically across the world, the scientific community can no longer neglect the need for research focusing on ADRDs among underrepresented ethnoracial diverse groups. The Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART; alz.org/ISTAART) comprises a number of professional interest areas (PIAs), each focusing on a major scientific area associated with ADRDs. We leverage the expertise of the existing international cadre of ISTAART scientists and experts to synthesize a cross-PIA white paper that provides both a concise "state-of-the-science" report of ethnoracial factors across PIA foci and updated recommendations to address immediate needs to advance ADRD science across ethnoracial populations.

Comparative Study of Protein Expression Levels of Five Plaque Biomarkers and Relation with Carotid Plaque Type Classification in Patients after Carotid Endarterectomy

Atherosclerosis is an inflammatory process resulting in local plaque deposition in the vessel wall of arteries with symptoms to various areas of vascular tree. Identification of patients with progressive advanced atherosclerotic disease is mainly based on the known characteristics of the vulnerable or recently ruptured plaque. Molecular and cellular features associated with the vulnerable plaque are considered potential diagnostic markers for plaque rupture and thrombosis. Here, protein expression levels of the metalloproteases MMP-1, MMP-9, osteopontin (OPN), and cytokines TNFα and IL-6 in tissue extracts of carotid plaques in patients after endarterectomy were estimated by Western immunoblotting, after SDS-PAGE analysis and evaluated based on the ultrasonographic plaque morphology. The gender and age effect was also examined. MMP-1, MMP-9, and IL-6 were expressed in higher levels compared to OPN and TNFa as well as in symptomatic (with type II and III carotid plaque classification) than asymptomatic (type IV) patients with differences considered statistically significant (P values <0.05). A significant positive correlation between MMP-1 and IL-6 (with Pearson correlation coefficient 0.748) is also notable. The data give further insight into the possible role of specific biomarker and enhance the need for further studies in order to clarify the proper one(s) for detection of the vulnerable plaque and help identify patients at risk for cardiovascular events.

Serum tumor necrosis factor α levels are associated with new ischemic brain lesions after carotid artery stenting

OBJECTIVE

New diffusion-weighted imaging (DWI) lesions on magnetic resonance imaging (MRI) after carotid artery stenting (CAS) are associated with an increased risk of future cerebrovascular events. Therefore, we evaluated the association between the expression levels of serum inflammatory markers and new DWI lesions after CAS and the presence of intraplaque hemorrhage (IPH). We also explored the mechanisms underlying this association.

METHODS

A total of 225 inpatients with severe carotid artery stenosis were consecutively enrolled in this cohort study. Serum inflammatory marker levels were detected in all patients by enzyme-linked immunosorbent assay. In the final analysis, 128 patients who underwent CAS and received pretreatment and post-treatment MRI scans were enrolled. DWI was performed to detect new ischemia brain lesions. T1-weighted, T2-weighted, and time-of-flight sequences were also conducted to identify IPH.

RESULTS

Serum tumor necrosis factor α (TNF-α) levels were significantly higher in symptomatic patients as well as in IPH+ patients identified by carotid MRI. New DWI lesions were identified in 50% of patients after CAS. Univariate analysis showed that DWI+ patients after CAS exhibited older mean age, higher mean TNF-α levels, and more IPH on preoperative MRI and were less likely to have right carotid stenosis than DWI- patients. Multivariate logistic regression analyses revealed that serum TNF-α concentrations were associated with new DWI lesions after CAS (odds ratio, 1.245; 95% confidence interval, 1.068-1.451; P = .005). Finally, the specificity and sensitivity of serum TNF-α levels in predicting DWI+ patients after CAS were 0.828 and 0.453, respectively.

CONCLUSIONS

Higher serum TNF-α levels are associated with a higher likelihood of new DWI lesions after CAS and the presence of IPH. Therefore, TNF-α is a potentially valuable predictor of acute ischemic cerebral lesions after CAS and the presence of IPH.

Association Between Serum Tumor Necrosis Factor Receptor 1 and Trajectories of Functional Status: The Northern Manhattan Study

We hypothesized that tumor necrosis factor receptor 1 (TNFR1) levels are associated with long-term trajectories of functional status independently of vascular risk factors and the occurrence of stroke and myocardial infarction (MI) during follow-up. In the Northern Manhattan Study, stroke-free persons aged ≥40 years in northern Manhattan (New York, New York) had annual assessments with the Barthel index (BI) for a median of 13 years (1993-2015). Assessment of baseline demographic factors, risk factors, and laboratory studies included measurement of TNFR1 (n = 1,863). Generalized estimating equations models were used to estimate standardized associations between TNFR1 and 1) baseline functional status and 2) change in function over time, adjusting for demographic factors, vascular risk factors, social variables, cognition, and depression, as well as stroke and MI occurrence during follow-up. The mean age of participants was 70 (standard deviation (SD), 10) years; 66% were women, and 55% were Hispanic. The mean TNFR1 level was 2.57 mg/L. TNFR1 was associated with baseline BI (-0.93 BI points per SD increment in TNFR1; 95% confidence interval: -1.59, -0.26) and change over time (-0.36 BI points per year per SD increment in TNFR1; 95% confidence interval: -0.69, -0.03). In this large population-based study, higher TNFR1 levels were associated with greater baseline disability and disability over time, even with adjustment for baseline covariates and stroke and MI occurrence during follow-up.

Circulating TNF receptors predict cardiovascular disease in patients with chronic kidney disease

Cardiovascular disease (CVD) is the main public health problem in patients with chronic kidney disease (CKD); however, there is no established biomarker for predicting CVD morbidity and mortality in CKD. The aim of this study was to evaluate the role of circulating tumor necrosis factor receptors (cTNFRs) in predicting CVD risk in CKD patients.We prospectively recruited 984 patients with CKD from 11 centers between 2006 and 2012. The levels of cTNFR1 and cTNFR2 were determined by performing an enzyme-linked immunosorbent assay. During the mean follow-up period of 4 years, 36 patients experienced a CVD event. The median serum concentrations of cTNFR1 and cTNFR2 were 2703.4 (225.6-13,057.7) and 5661.0 (634.9-30,599.6) pg/mL, respectively, and the cTNFR1 level was closely correlated with the cTNFR2 level (r = 0.86, P < .0001). The urinary protein-to-creatinine ratio (UPCR) and estimated glomerular filtration rate (eGFR) were significantly correlated with the cTNFR2 level (r = 0.21 for UPCR, r = -0.67 for eGFR; P < .001 for all). Similar correlations were observed for serum cTNFR1 (r = 0.21 for UPCR, r = -0.75 for eGFR; P < .001 for all). In the Cox proportional hazard analyses, cTNFR1 (hazard ratio [HR] 2.506, 95% confidence interval [CI] 1.186-5.295, P = .016) and cTNFR2 (HR 4.156, 95% CI 1.913-9.030, P < .001) predicted CVD risk even after adjustment for clinical covariates, such as UPCR, eGFR, and high-sensitivity C-reactive protein. cTNFR1 and 2 are associated with CVD and other risk factors in CKD, independently of eGFR and UPCR. Furthermore, cTNFRs could be relevant predictors of CVD in CKD patients.

Soluble Tumor Necrosis Factor Receptors and Arterial Stiffness in Patients With Coronary Atherosclerosis

BACKGROUND

Soluble forms of tumor necrosis factor receptors (sTNFRs) are emerging target molecules of inflammatory disease. However, their role in vascular biology is not well known. This study was performed to investigate the association between serum concentrations of sTNFRs and arterial stiffness.

METHODS

A total of 117 consecutive patients with suspected coronary artery disease (CAD) (63.6 ± 11.0 years; men, 65%) who were referred for invasive coronary angiography (ICA) were prospectively enrolled. Arterial blood sTNFR1 and sTNFR2 were measured using commercially available ELISA kits. Brachial-ankle pulse wave velocity (baPWV) measurements were made within 24 hours of blood sampling for sTNFRs measurement.

RESULTS

Most of the patients (86.3%) had significant CAD (stenosis ≥ 50%) in ICA. In simple linear regression analyses, there were significant positive correlations of baPWV with sTNFR1 (r = 0.483, P < 0.001) and sTNFR2 (r = 0.366, P < 0.001). In multiple linear regression analyses, sTNFR1 (β = 0.316, P < 0.001) and sTNFR2 (β = 0.235, P = 0.005) had independent association with baPWV even after controlling for potential confounders.

CONCLUSION

sTNFR1 and sTNFR2 were independently associated with baPWV in patients undergoing ICA. This result may extend previous knowledge on close interactions between inflammation and arterial stiffening.

Inflammatory Markers and Outcomes After Lacunar Stroke: Levels of Inflammatory Markers in Treatment of Stroke Study

BACKGROUND AND PURPOSE

We hypothesized that concentrations of interleukin 6 (IL-6), serum amyloid A, tumor necrosis factor-α receptor 1, CD40 ligand, and monocyte chemoattractant protein 1 would predict recurrent ischemic stroke and major vascular events after recent lacunar stroke.

METHODS

Levels of Inflammatory Markers in the Treatment of Stroke (LIMITS) was an international, multicenter, prospective ancillary biomarker study nested within the Secondary Prevention of Small Subcortical Strokes (SPS3) study, a Phase III trial in patients with recent lacunar stroke. Crude and Adjusted Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CI) for recurrence risks.

RESULTS

Among 1244 patients with lacunar stroke (mean age, 63.3±10.8 years), there were 115 major vascular events (stroke, myocardial infarction, and vascular death). The risk of major vascular events increased with elevated concentrations of both tumor necrosis factor-α receptor 1 (adjusted HR per SD, 1.21; 95% CI, 1.05-1.41; P=0.01) and IL-6 (adjusted HR per SD, 1.10; 95% CI, 1.02-1.19; P=0.008). Compared with the bottom quartile (tumor necrosis factor-α receptor 1 <2.24 ng/L), those in the top quartile of tumor necrosis factor-α receptor 1 (>3.63 ng/L) were at twice the risk of major vascular events after adjusting for demographics (partially adjusted HR, 1.98; 95% CI, 1.11-3.52), though the effect attenuated after adjusting for other risk factors and statin use (adjusted HR, 1.68; 95% CI, 0.93-3.04). Serum amyloid A, CD40 ligand, and monocyte chemoattractant protein 1 were not associated with prognosis.

CONCLUSIONS

Among recent lacunar stroke patients, IL-6 and TNF receptor concentrations predict risk of recurrent vascular events, and they are associated with the effect of antiplatelet therapies.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059306.

Fibroblast Growth Factor 23 Is Associated With Carotid Plaque Presence and Area: The Northern Manhattan Study

OBJECTIVE

Elevated fibroblast growth factor 23 (FGF23), a hormone that regulates phosphate homeostasis, has been associated with mortality, cardiovascular events, and stroke, and to arterial calcification in chronic kidney disease, but its role in atherosclerosis is unclear and population-based studies are lacking. We hypothesized that elevated FGF23 would associate with carotid plaque presence, area, and echogenicity in the race/ethnically diverse community-based Northern Manhattan Study (NOMAS) sample.

APPROACH AND RESULTS

There were 1512 stroke-free NOMAS participants with FGF23 and 2-dimensional carotid ultrasound data (mean age, 68±9 years; 61% women; 62% Hispanic, 18% black, and 18% white). We used multivariable linear and logistic regression to evaluate FGF23, continuously and by quintiles, as a correlate of carotid plaque, plaque area (cubic root transformed), and echogenicity adjusting for sociodemographic and vascular risk factors. Participants with FGF23 levels in the top quintile were more likely to have carotid plaque (odds ratio, 1.49; 95% confidence interval, 1.02-2.19; P=0.04) and larger plaque area (β=0.32 mm(2), 95% confidence interval, 0.10-0.53 mm(2); P=0.004) than those in the lowest quintile, adjusting for estimated glomerular filtration rate, demographics, and vascular risk factors. Linear regression models also showed that log transformed FGF23 (LnFGF23) associated with greater odds of plaque presence (odds ratio, 1.26 per LnFGF23; 95% confidence interval, 1.01-1.58; P=0.04), and plaque area (β=0.19 mm(2) per LnFGF23; 95% confidence interval, 0.07-0.31 mm(2); P=0.002).

CONCLUSIONS

Higher FGF23 associated with greater likelihood and burden of carotid atherosclerosis independent of CKD. Atherosclerosis may be a mechanism through which FGF23 increases cardiovascular events and stroke.

Soluble TNF and IL-6 receptors: indicators of vascular health in women without cardiovascular disease

Cytokine receptor subunits are released from cells in a regulated manner and circulate in soluble forms at concentrations that are orders of magnitude greater than the concentrations of the cytokines themselves. The purpose of this study was to determine if the circulating concentrations of soluble receptor subunits for interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6) might serve as early indicators of vascular dysfunction independent of the traditional cardiovascular disease (CVD) risk factors in women. Healthy women, aged 20-50 years (n = 36), were assessed for circulating concentrations of the cytokines IL-1β, IL-6 and TNFα and the soluble cytokine receptor subunits interleukin-1 receptor type I (sIL-1RI), sIL-1RII, sIL-6Rα, glycoprotein 130 (s-gp130), soluble TNF receptor type 1 (sTNFR1), and sTNFR2, along with traditional CVD risk factors. Cytokine receptor subunit expression on mononuclear cells and the release of these subunits in vitro were also determined. Brachial artery flow-mediated dilation (FMD), carotid intima-media thickness (cIMT) and carotid-femoral pulse wave velocity (cfPWV) were assessed by ultrasonography and Doppler probes. Circulating sIL-6Rα correlated negatively with FMD (r = -0.56, p = 0.007) independent of age and other CVD risk factors. Circulating sTNFR1 correlated positively with cfPWV (r = 0.60, p = 0.002). TNFR1 receptor expression on monocytes correlated positively with cIMT (r = 0.51, p = 0.004). Plasma concentrations of IL-1β, IL-6 and TNFα were not significantly associated with FMD, cIMT or cfPWV. These data suggest that the receptors for IL-6 and TNFα, rather than the cytokines themselves, may be better indicators of early vascular changes that are associated with CVD.

Acculturative stress and inflammation among Chinese immigrant women

OBJECTIVE

Among Chinese immigrant populations, increasing duration of US residence is associated with elevated risk for various chronic diseases. Although life-style changes after migration have been extensively studied in immigrant populations, the psychosocial impact of acculturative stress on biological markers of health is less understood. Thus, the purpose of the present study is to examine associations between acculturative stress and inflammatory markers in a Chinese immigrant population.

METHODS

Study participants (n = 407 foreign-born Chinese American women) completed questionnaires assessing levels of stress, including acculturative stress and positive and negative life events in the previous year. Participant height and weight were measured using standard protocols, and blood samples were drawn for assessment of circulating serum levels of C-reactive protein (CRP) and soluble tumor necrosis factor receptor 2 (sTNFR2).

RESULTS

Higher levels of acculturative stress were significantly associated with higher levels of CRP (B = 0.07, 95% confidence interval = 0.01-0.13, p = .031) and sTNFR2 (B = 0.02, 95% confidence interval = 0.004-0.03, p = .012), adjusting for age and body mass index. The latter association was no longer statistically significant when overall acculturation (i.e., identification with American culture) was included in the model. Life events were not associated with CRP or sTNFR2.

CONCLUSIONS

This is one of the first studies to demonstrate that acculturative stress is associated with inflammatory markers in a Chinese immigrant population. Replication in other immigrant samples is needed to fully establish the biological correlates and clinical consequences of acculturative stress.

Nonconvulsive seizures in subarachnoid hemorrhage link inflammation and outcome

OBJECTIVE

Nonconvulsive seizures (NCSz) are frequent following acute brain injury and have been implicated as a cause of secondary brain injury, but mechanisms that cause NCSz are controversial. Proinflammatory states are common after many brain injuries, and inflammation-mediated changes in blood-brain barrier permeability have been experimentally linked to seizures.

METHODS

In this prospective observational study of aneurysmal subarachnoid hemorrhage (SAH) patients, we explored the link between the inflammatory response following SAH and in-hospital NCSz studying clinical (systemic inflammatory response syndrome [SIRS]) and laboratory (tumor necrosis factor receptor 1 [TNF-R1], high-sensitivity C-reactive protein [hsCRP]) markers of inflammation. Logistic regression, Cox proportional hazards regression, and mediation analyses were performed to investigate temporal and causal relationships.

RESULTS

Among 479 SAH patients, 53 (11%) had in-hospital NCSz. Patients with in-hospital NCSz had a more pronounced SIRS response (odds ratio [OR]=1.9 per point increase in SIRS, 95% confidence interval [CI]=1.3-2.9), inflammatory surges were more likely immediately preceding NCSz onset, and the negative impact of SIRS on functional outcome at 3 months was mediated in part through in-hospital NCSz. In a subset with inflammatory serum biomarkers, we confirmed these findings linking higher serum TNF-R1 and hsCRP to in-hospital NCSz (OR=1.2 per 20-point hsCRP increase, 95% CI=1.1-1.4; OR=2.5 per 100-point TNF-R1 increase, 95% CI=2.1-2.9). The association of inflammatory biomarkers with poor outcome was mediated in part through NCSz.

INTERPRETATION

In-hospital NCSz were independently associated with a proinflammatory state following SAH as reflected in clinical symptoms and serum biomarkers of inflammation. Our findings suggest that inflammation following SAH is associated with poor outcome and that this effect is at least in part mediated through in-hospital NCSz.

Soluble tumor necrosis factor receptors and heart failure risk in older adults: Health, Aging, and Body Composition (Health ABC) Study

BACKGROUND

Tumor necrosis factor (TNF) levels are associated with risk for heart failure (HF). The soluble TNF type 1 (sTNF-R1) and type 2 (sTNF-R2) receptors are elevated in patients with manifest HF, but whether they are associated with risk for incident HF is unclear.

METHODS AND RESULTS

Using Cox proportional hazard models, we examined the association between baseline levels of sTNF-R1 and sTNF-R2 with incident HF risk among 1285 participants of the Health, Aging, and Body Composition Study (age, 74.0±2.9 years; 51.4% women; 41.1% black). At baseline, median (interquartile range) of TNF, sTNF-R1, and sTNF-R2 levels was 3.14 (2.42-4.06), 1.46 (1.25-1.76), and 3.43 (2.95-4.02) ng/mL, respectively. During a median follow-up of 11.4 (6.9-11.7) years, 233 (18.1%) participants developed HF. In models controlling for other HF risk factors, TNF (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.02-1.61 per log2 increase) and sTNF-R1 (HR, 1.68; 95% CI, 1.15-2.46 per log2 increase), but not sTNF-R2 (HR, 1.15; 95% CI, 0.80-1.63 per log2 increase), were associated with a higher risk for HF. These associations were consistent across whites and blacks (TNF, sTNF-R1, sTNF-R2; interaction P=0.531, 0.091, and 0.795, respectively) and in both sexes (TNF, sTNF-R1, sTNF-R2; interaction P=0.491, 0.672, and 0.999, respectively). TNF-R1 was associated with a higher risk for HF with preserved versus reduced ejection fraction (HR, 1.81; 95% CI, 1.03-3.18; P=0.038 for preserved versus HR, 0.90; 95% CI, 0.56-1.44; P=0.667 for reduced ejection fraction; interaction P=0.05).

CONCLUSIONS

In older adults, elevated levels of sTNF-R1 are associated with increased risk for incident HF. However, addition of TNF-R1 to the previously validated Health ABC HF risk model did not demonstrate material improvement in net discrimination or reclassification.

Atherosclerotic biomarkers and aortic atherosclerosis by cardiovascular magnetic resonance imaging in the Framingham Heart Study

BACKGROUND

The relations between subclinical atherosclerosis and inflammatory biomarkers have generated intense interest but their significance remains unclear. We sought to determine the association between a panel of biomarkers and subclinical aortic atherosclerosis in a community-based cohort.

METHODS AND RESULTS

We evaluated 1547 participants of the Framingham Heart Study Offspring cohort who attended the 7th examination cycle and underwent both cardiovascular magnetic resonance imaging (CMR) and assays for 10 biomarkers associated with atherosclerosis: high-sensitivity C-reactive protein, fibrinogen, intercellular adhesion molecule-1, interleukin-6, interleukin-18, lipoprotein-associated phospholipase-A2 activity and mass, monocyte chemoattractant protein-1, P-selectin, and tumor necrosis factor receptor-2. In logistic regression analysis, we found no significant association between the biomarker panel and the presence of aortic plaque (global P=0.53). Using Tobit regression with aortic plaque as a continuous variable, we noted a modest association between biomarker panel and aortic plaque volume in age- and sex-adjusted analyses (P=0.003). However, this association was attenuated after further adjustment for clinical covariates (P=0.09).

CONCLUSIONS

In our community-based cohort, we found no significant association between our multibiomarker panel and aortic plaque. Our results underscore the strengths and limitations of the use of biomarkers for the identification of subclinical atherosclerosis and the importance of traditional risk factors.

Tumour necrosis factor receptor 1 and mortality in a multi-ethnic cohort: the Northern Manhattan Study

OBJECTIVE

to study the association between soluble tumour necrosis factor receptor 1 (sTNFR1) levels and mortality in the population-based Northern Manhattan Study (NOMAS).

METHODS

NOMAS is a multi-ethnic, community-based cohort study with mean 8.4 years of follow-up. sTNFR1 was measured using ELISA. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals (HR, 95% CI) for the association of sTNFR1 with risk of all-cause mortality after adjusting for relevant confounders.

RESULTS

sTNFR1 measurements were available in 1,862 participants (mean age 69.2 ± 10.2 years) with 512 all-cause deaths. Median sTNFR1 was 2.28 ng/ml. Those with sTNFR1 levels in the highest quartile (Q4), compared with those with sTNFR1 in the lowest quartile (Q1), were at an increased risk of all-cause mortality (adjusted HR: 1.8, 95% CI: 1.4-2.4) and non-vascular mortality (adjusted HR: 2.5, 95% CI: 1.5-3.6), but not vascular mortality (adjusted HR: 1.3, 95% CI: 0.9-1.9). There were interactions between sTNFR1 quartiles and medical insurance-status [likelihood ratio test (LRT) with 3 degrees of freedom, Pinteraction = 0.02] and alcohol consumption (LRT with 3 degrees of freedom, Pinteraction < 0.01) for all-cause mortality. In participants with no insurance or Medicaid, those with sTNFR1 in the top quartile had nearly a threefold increased risk of total mortality than the lowest quartile (adjusted HR: 2.9, 95% CI: 1.9-4.4).

CONCLUSION

in this multi-ethnic cohort, sTNFR1 was associated with all-cause and non-vascular mortality, particularly among those of a lower socioeconomic status.

Inflammatory markers in patients with internal carotid artery stenosis

INTRODUCTION

Available reports underline the significance of the inflammatory process in the development, progression and destabilisation of atherosclerotic plaques in the internal carotid artery (ICA). The aim of this study was to evaluate the relationship between the degree of ICA stenosis, ultrasound plaque morphology and serum concentration of selected inflammatory markers.

MATERIAL AND METHODS

Sixty-five patients with ICA stenosis > 50% (39 symptomatic) and 30 healthy volunteers were enrolled in the study. Clinical, neurological examination and laboratory evaluation (leucocyte count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fibrinogen, tumour necrosis factor-α (TNF-α), interleukins (1β, 6 and 10), anti-cytomegalovirus IgG antibody titre) were performed. Stenosis grade ≥ 70%, ulcerations on the plaque surface and a hypoechoic (or predominantly hypoechoic) structure of the plaque, obtained by colour-coded duplex examination, were accepted as the characteristics of unstable stenoses.

RESULTS

Unstable ultrasound features of ICA stenosis were found significantly more often in symptomatic than in asymptomatic patients (71.79% vs. 30.71% for stenosis degree ≥ 70%, p = 0.001 and 61.23% vs. 38.46% for unstable plaque morphology, p = 0.01). Patients with ICA stenosis had significantly higher serum concentrations of interleukin-6, fibrinogen, ESR and higher CRP values than the individuals from the control group (p = 0.001, p = 0.009, p = 0.036, p = 0.009 respectively). Patients with unstable plaques structure had significantly higher concentrations of TNF-α, interleukin-6, fibrinogen, higher number of leukocytes, monocytes and higher CRP values than patients with stable plaques (p = 0.008, p = 0.049, p = 0.012, p = 0.0002, p = 0.006, p = 0.0003 respectively). No significant differences in above-mentioned parameters between the groups with stenosis < 70% and ≥ 70% were found.

CONCLUSIONS

There is a relationship between the activity of the selected inflammatory markers in serum and atherosclerotic unstable internal carotid artery stenosis. There is no relationship between serum concentration of inflammatory markers and degree of carotid artery stenosis.

Inflammation and hypertension: are there regional differences?

Hypertension is a chronic disease with global prevalence and incidence rapidly increasing in low and medium income countries. The surveillance of cardiovascular risk factors, such as hypertension, is a global health priority in order to estimate the burden and trends, to appropriately direct resources, and to measure the effect of interventions. We propose here that the adoption of Western lifestyles in low and middle incomes countries has dramatically increased the prevalence of abdominal obesity, which is the main source of proinflammatory cytokines, and that the vascular systemic inflammation produced by adipose tissue contributes to the development of hypertension. The concentration of proinflammatory cytokines is higher in the Latin American population than that reported in developed countries, suggesting a higher susceptibility to develop systemic low-degree inflammation at a given level of abdominal obesity. These particularities are important to be considered when planning resources for health care programs. Moreover, studying these singularities may provide a better understanding of the causes of the burden of cardiovascular risk factors and the remarkable variability in the prevalence of these medical conditions within and between countries.

The role and importance of gene polymorphisms in the development of atherosclerosis

The development of atherosclerosis is a multifactorial process. The purpose of the study was to examine three genetic polymorphisms playing a role in the metabolic processes underlying the disease. We compared the data of 348 atherosclerotic non-diabetic patients with 260 atherosclerotic diabetic patients and 384 healthy controls. We analyzed the prevalence of myocardial infarction and stroke in three different groups of patients carrying different polymorphisms. It was proved that if the mutant TT eNOS Glu298ASP variant is present, a significantly higher number of myocardial infarctions can be observed than in patients carrying heterozygote GT or normal GG genotype. We proved that in the case of MTHFR 677CT heterozygote variants, the occurrence of myocardial infarction is significantly higher and the difference is also significant in case of the 677TT homozygote variant. It was verified that among patients with the mutant TNF-α AA genotype the occurrence of cardiovascular events was significantly higher. Screening the genetically high risk groups on the long run should be considered as an early detection opportunity that may give better chances for prevention and treatment. Understanding the inflammatory mechanisms of the atherosclerosis may give new therapeutical targets to pharmacologists.

Cardiovascular biomarkers and their utility in the older adult

Cardiovascular disease is the leading cause of morbidity and mortality in individuals over the age of 65 yet diagnosis, risk stratification and management continue to be more challenging than in younger adults due to the vast heterogeneity seen in this population. The current literature validates the use of biomarkers in addition to traditional risk assessment tools in younger and middle aged adults. The evidence for biomarkers in this older population is sparse; this review examines the epidemiological association of current biomarkers in the field and the utility of these markers in the diagnosis, risk discrimination and management of cardiovascular disease.

The metabolic syndrome and cognitive performance: the Northern Manhattan Study

BACKGROUND

The metabolic syndrome (MetS) is a risk factor for diabetes, stroke, myocardial infarction, and increased mortality, and has been associated with cognition in some populations. We hypothesized that MetS would be associated with lower Mini-Mental State Examination (MMSE) scores in a multi-ethnic population, and that MetS is a better predictor of cognition than its individual components or diabetes.

METHODS

We conducted a cross-sectional analysis among 3,150 stroke-free participants. MetS was defined by the modified National Cholesterol Education Program guidelines-Adult Treatment Panel III (NCEP-ATPIII) criteria. Linear regression and polytomous logistic regression estimated the association between MMSE score and MetS, its individual components, diabetes, and inflammatory biomarkers.

RESULTS

MetS was inversely associated with MMSE score (unadjusted β = -0.67; 95% CI -0.92, -0.41). Adjusting for potential confounders, MetS was associated with lower MMSE score (adjusted β = -0.24; 95% CI -0.47, -0.01), but its individual components and diabetes were not. Those with MetS were more likely to have an MMSE score of <18 than a score of ≥ 24 (adjusted OR = 1.94; 95% CI 1.26, 3.01). There was an interaction between MetS and race-ethnicity, such that MetS was associated with lower MMSE score among non-Hispanic whites and Hispanics but not non-Hispanic blacks.

CONCLUSIONS

MetS was associated with lower cognition in a multi-ethnic population. Further studies of the effect of MetS on cognition are warranted, and should account for demographic differences.

Inflammatory and neuroendocrine biomarkers of prognosis after ischemic stroke

Stroke is the third leading cause of mortality in the USA and one of the leading causes of severe morbidity. It is important to provide stroke patients and physicians with the most accurate prognostic information to optimize care and allocation of healthcare resources. Reliable prognostic markers available during the initial phase after acute stroke may aid clinical decision-making. Several interesting candidate biomarkers have been studied to address prognostic questions; this article will focus on selected inflammatory and neuroendocrine markers. The utility of a biomarker is defined by its ability to improve clinical decision-making and add timely information beyond that readily available from clinical examination and routine imaging. This aim has not been completely achieved yet for any biomarkers, but promising data are available and further studies are ongoing.

Upregulation of Inflammatory Mediators in End-Stage Renal Disease as Measured Using Biochip Array Technology

Systemic vascular changes contribute to both the pathogenesis and thrombotic comorbidities of end-stage renal disease (ESRD). This study aims to profile various biomarkers and better understand their role in the pathogenesis of ESRD. Plasma samples from 49 patients with ESRD and 56 control individuals were analyzed for markers for inflammation, specifically C-reactive protein (CRP), tumor necrosis factor receptor 1 (TNFR1), neutrophil gelatinase-associated lipocalin (NGAL); thrombomodulin (TM); neuron-specific enolase (NSE), and thrombosis-D-dimer (DD). Compared to controls, all markers studied showed a statistically significant upregulation in patients with ESRD. These results indicate a polypathologic process in patients with ESRD, leading to cardiovascular and cerebrovascular events. However, the clinical significance of previously untested markers, such as TNFR1, NGAL, and NSE, still needs to be further explored. This study further validates the role of endothelial damage and endogenous thrombotic processes in ESRD as evidenced by the increased levels of TM and DD.

Tumornecrosis-factor-α 308 GA polymorphism in atherosclerotic patients

The development of the atherosclerosis is a multifactorial process, where the clinical pattern is determined by environmental and genetic factors. Except for the classical risk factors of atherosclerosis (hypertension, lipid-metabolic disorders, diabetes, smoking) the clinical signs can be influenced by the genetic variants (polymorphisms) of the enzymes, which are responsible for the endothelial cell function and for the thrombotic factors. In our examination our aim was to define the TNF-α 308GA polymorphisms in atherosclerotic diabetic, atherosclerotic non-diabetic and healthy patients. We found correlation of the frequency of myocardial infarction and stroke in atherosclerotic diabetic and atherosclerotic non-diabetic patients. We proved that among patients with mutant TNF-α AA genotype the occurrence of cardiovascular events is significantly higher: Mutant AA homozygous genotype: control group 1, 6%, MI group 10,7%, p < 0,005, OR: 8,17 versus Normal GG allele: control group 76,7%, MI group 61,3%. The TNF-α AA genotype can have a clinical importance as a prognostic and therapeutic marker, although further studies are needed to confirm this hypothesis.

Determinants of inflammatory markers in a bi-ethnic population

BACKGROUND

Inflammation is a common pathophysiological pathway for a number of chronic diseases, and is strongly influenced by sociodemographic factors and lifestyle. Less is known about factors that may influence the inflammatory response in individuals of distinct ethnic backgrounds. Therefore, this study examined the relationship between ethnicity and blood levels of inflammatory markers in a sample of non-smoking church-goers.

METHODS

In a cross-sectional investigation, 508 men and women (> 35 years old, 62% White, 38% Black) participated in the Biopsychosocial Religion and Health substudy of the Adventist Health Study 2. The contribution of socioeconomic status (education level and difficulty meeting expenses for basic needs) and health covariates (exercise, vegetarian or other type of diet, body mass index, and presence of inflammatory conditions) toward serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) was assessed with linear regression models. Levels of interleukin-10 (IL-10), an anti-inflammatory marker, were also assessed.

RESULTS

Blacks showed higher levels of CRP and IL-6 than Whites. Controlling for sociodemographic and health variables attenuated the ethnic difference in CRP while IL-6 levels remained higher in Blacks than in Whites (beta = .118; 95% confidence interval = .014-.206; P = .025). Ethnic differences in IL-10 and TNF-alpha were not found. Vegetarian diet was associated with lower CRP levels while exercise frequency was associated with higher IL-10 levels.

CONCLUSION

Higher susceptibility of Blacks to inflammatory diseases may reflect higher IL-6, which could be important in assessing health disparities among Blacks and Whites. Vegetarian diet and exercise may counteract effects of disparities.

The Levels of Inflammatory Markers in the Treatment of Stroke study (LIMITS): inflammatory biomarkers as risk predictors after lacunar stroke

BACKGROUND

Inflammation is increasingly recognised as playing a central role in atherosclerosis, and peripheral blood markers of inflammation have been associated with incident and recurrent cardiac events. The relationship of these potentially modifiable risk markers to prognosis after ischaemic stroke is less clear. The Levels of Inflammatory Markers in the Treatment of Stroke (LIMITS) study will address hypotheses related to the role of inflammatory markers in secondary stroke prevention in an efficient manner using the well-established framework of the Secondary Prevention of Small Subcortical Strokes (SPS3) trial (NCT00059306).

METHODS

SPS3 is an ongoing Phase III multicentre secondary prevention trial focused on preventing recurrent stroke in patients with small vessel ischaemic stroke, or lacunes. In SPS3, patients are assigned in a factorial design to aspirin vs. aspirin plus clopidogrel, and to usual vs. aggressive blood pressure targets. The purpose of LIMITS is to determine whether serum levels of inflammatory markers - including high-sensitivity C-reactive protein, serum amyloid A, CD40 ligand, and monocyte chemoattractant protein-1 - predict recurrent stroke and other vascular events among lacunar stroke patients. The project will also determine whether these markers predict which people will respond best to dual antiplatelet therapy with clopidogrel and aspirin, as well the relationship to cognitive function.

ANALYSIS

plan Multivariable Cox proportional hazard regression modeling will be used to estimate hazard ratios for the effect of marker levels on risk of recurrent stroke and other outcomes after adjusting for additional potential risk factors, including age, gender, ethnicity, treatment arm, and traditional stroke risk factors. Interactions between marker levels and treatment assignment for both arms of the SPS3 study will be assessed. Observations will be censored at the time of last follow-up visit.

CONCLUSIONS

LIMITS represents an efficient approach to the identification of novel inflammatory biomarkers for use in risk prediction and treatment selection in patients with small vessel disease.

Aldose reductase regulates vascular smooth muscle cell proliferation by modulating G1/S phase transition of cell cycle

Abnormal proliferation of vascular smooth muscle cells (VSMC) is a key feature of development of cardiovascular complications, atherosclerosis, and restenosis. Patients with diabetes have higher risk for restenosis after coronary angioplasty than nondiabetic patients due to hyperglycemia-induced release of cytokines such as TNF-alpha. However, the molecular mechanisms regulating VSMC proliferation remain unclear. Herein, we report that inhibition of the polyol pathway enzyme aldose reductase (AR) prevents high glucose (HG)- and/or TNF-alpha-induced VSMC proliferation by accumulating cells at the G1 phase of the cell cycle. Treatment of VSMC with AR inhibitor sorbinil prevented HG- as well as TNF-alpha-induced phosphorylation of retinoblastoma protein and activation of E2F-1. Inhibition of AR also prevented HG- and TNF-alpha-induced phosphorylation of cyclin-dependent kinase (cdk)-2 and expression of G1/S transition regulatory proteins such as cyclin D1, cyclin E, cdk-4, c-myc, and proliferative cell nuclear antigen. More importantly, inhibition of AR prevented the increased expression of E2F-1 and proliferative cell nuclear antigen in diabetic rat aorta. Treatment of VSMC with the most abundant and toxic lipid aldehyde 4-hydroxy-trans-2-nonenal (HNE) or its glutathione conjugate [glutathionyl (GS)-HNE] or AR-catalyzed product of GS-HNE, GS-1,4-dihydroxynonane, resulted in increased E2F-1 expression. Inhibition of AR prevented HNE- or GS-HNE-induced but not GS-1,4-dihydroxynonane-induced up-regulation of E2F-1. Collectively, these results show that AR could regulate HG- and TNF-alpha-induced VSMC proliferation by altering the activation of G1/S-phase proteins such as E2F-1, cdks, and cyclins. Thus, inhibition of AR may be a useful therapeutic approach in preventing vascular complications.

Lipids and carotid plaque in the Northern Manhattan Study (NOMAS)

Background

Lipids, particularly low-density (LDL) and high-density (HDL) lipoproteins, are associated with increased risk of stroke and cardiovascular disease, probably due to atherosclerosis. The objective of this cross-sectional analysis was to investigate the relation between blood lipids and carotid plaque.

Methods

As part of a prospective population-based study to determine the incidence and risk factors of stroke in a multiethnic population, we evaluated 1804 participants with lipid measurements and B-mode ultrasound of carotid arteries (mean age 69 +/- 10 years; 40% men; 51% Hispanic, 26% black, 23% white). The association between lipid parameters and carotid plaque was analyzed by multiple logistic regression.

Results

Plaque was present in 61% of participants. Mean total cholesterol was 202 +/- 41 mg/dl. After controlling for other lipid parameters, demographics, and risk factors, the only cholesterol subfraction associated with carotid plaque was LDL (OR per standard deviation (SD) = 1.14, 95% CI 1.02-1.27). Neither HDL nor triglycerides independently predicted carotid plaque. Apolipoprotein B (ApoB) was also associated with risk of plaque (OR per SD = 1.29, 95% CI 1.03-1.60). Apolipoprotein A-I (apoA-1) was associated with a decrease in multiple plaques (OR per SD = 0.76, 95% CI 0.60-0.97), while lipoprotein a was associated with an increased risk of multiple plaques (OR per SD = 1.31, 95% CI 1.03-1.66). ApoB:ApoA-I had the strongest relation with carotid plaque (OR per SD = 1.35, 95% CI 1.08-1.69).

Conclusions

Among the common lipid parameters, LDL has the strongest relation with carotid plaque. Other lipid precursor proteins such as ApoB and ApoA-I may be stronger predictors of subclinical atherosclerosis, however, and better targets for treatment to reduce plaque formation and risk of cerebrovascular disease.

Soluble tumor necrosis factor receptor 1 level is associated with left ventricular hypertrophy: the northern Manhattan study

BACKGROUND

Although inflammatory markers may be associated with risk of cardiovascular events, few data are available regarding these markers and their association with left ventricular hypertrophy (LVH). We sought to evaluate whether inflammatory markers were independently associated with LVH in a multiethnic population in northern Manhattan.

METHODS

A population-based cross-sectional study was conducted in 660 participants without stroke, who had undergone both transthoracic echocardiography and testing for soluble tumor necrosis factor receptor (sTNFR) 1, interleukin (IL)-6, and high-sensitivity C-reactive protein (hsCRP). LV mass was calculated according to an established formula. LVH was defined as LV mass >90th percentile of the participants.

RESULTS

The mean age was 67.4 +/- 8.8 years, 35.5% were men, 61.7% were Hispanic, 19.7% were black, and 18.6% were white. In univariate analyses, hsCRP, IL-6, and sTNFR1 were significantly associated with LV mass. Multiple linear regression analyses demonstrated that sTNFR1 (P = 0.0008) was associated with LV mass after adjusting for demographic and medical risk factors, but hsCRP and IL-6 were not. When all markers were included in the same model, sTNFR1 remained significant, but hsCRP and IL-6 did not. Compared with the lowest quartile of sTNFR1, those in the highest quartile were more likely to have LVH (odds ratio = 1.84, 95% confidence interval, 0.97-3.64, P = 0.06).

CONCLUSIONS

sTNFR1, but not hsCRP nor IL-6, is independently associated with increased LV mass. Chronic subclinical inflammation including the TNFR1-associated system may contribute to LVH.

Dietary total fat intake and ischemic stroke risk: the Northern Manhattan Study

BACKGROUND

Dietary fat intake is associated with coronary heart disease risk, but the relationship between fat intake and ischemic stroke risk remains unclear. We hypothesized that total dietary fat as part of a Western diet is associated with increased risk of ischemic stroke.

METHODS

As part of the prospective Northern Manhattan Study, 3,183 stroke-free community residents over 40 years of age underwent evaluation of their medical history and had their diet assessed by a food-frequency survey. Cox proportional hazard models calculated risk of incident ischemic stroke.

RESULTS

The mean age of participants was 69 years, 63% were women, 21% were white, 24% black and 52% Hispanic. During a mean of 5.5 years of follow-up, 142 ischemic strokes occurred. After adjusting for potential confounders, risk of ischemic stroke was higher in the upper quintile of total fat intake compared to the lowest quintile (HR 1.6, 95% CI 1.0-2.7). Total fat intake >65 g was associated with increased risk of ischemic stroke (HR 1.6, 95% CI 1.2-2.3). Risk was attenuated after controlling for caloric intake.

CONCLUSIONS

The results suggest that increased daily total fat intake, especially above 65 g, significantly increases risk of ischemic stroke.

Higher body mass index (BMI) is associated with reduced glucocorticoid inhibition of inflammatory cytokine production following acute psychosocial stress in men

BACKGROUND

Body mass index (BMI) and mental stress seem to exert part of their cardiovascular risk by eliciting inflammation. However, the adverse effects of stress on inflammatory activity with BMI are not fully understood. We investigated whether higher BMI is associated with reduced glucocorticoid inhibition of inflammatory cytokine production following stress in men while controlling for age and blood pressure. We measured glucocorticoid inhibition of lipopolysaccharide (LPS)-stimulated release of the proinflammatory cytokine tumor necrosis factor (TNF)-alpha.

METHODS

Forty-two men (age range 21-65 years; BMI range 21-34 kg/m(2)) underwent the Trier Social Stress Test (combination of mock job interview and mental arithmetic task). Whole blood samples were taken immediately before and after stress, and during recovery up to 60 min post-stress. Glucocorticoid sensitivity of LPS-stimulated TNF-alpha expression was assessed in vitro with and without coincubating increasing doses of dexamethasone. Moreover, salivary cortisol was measured during the experiment and on a normal day for assessment of baseline circadian cortisol.

RESULTS

Higher BMI was associated with lower glucocorticoid sensitivity of monocyte TNF-alpha production after stress (main effect of BMI: p<0.001) and with more pronounced decreases of glucocorticoid sensitivity following stress (interaction of stress-by-BMI: p=0.002). Neither LPS-stimulated TNF-alpha release nor baseline glucocorticoid sensitivity were associated with BMI. Similarly, BMI was not associated with salivary cortisol, either in reaction to stress or in circadian cortisol secretion.

CONCLUSIONS

Our data suggest that with increasing BMI, glucocorticoids are less able to inhibit TNF-alpha production following stress. This might suggest a new mechanism linking BMI with elevated risk for adverse cardiovascular outcomes following stress.

Chlamydia pneumoniae IgA and elevated level of IL-6 may synergize to accelerate coronary artery disease

OBJECTIVES

A strong association of cytokines [interleukin (IL)-6, IL-2 and tumor necrosis factor (TNF)-alpha] with atherosclerosis is well documented. However, their role in Chlamydia pneumoniae (Cp)-associated progression of coronary artery disease (CAD) is not well studied. Hence we evaluated the presence of these cytokines in CAD patients positive for Cp immunoglobulin (Ig) A (low, medium, and high levels) CAD and compared with controls. Also the physiological and baseline characteristics in IL-6 positive CAD patients were studied.

METHODS

During the period from March 2005 to June 2007, 192 CAD patients and controls attending the cardiology clinic of Safdarjung Hospital, New Delhi, India were enrolled. ELISA was performed for the estimation of Cp IgA, high sensitive C-reactive protein (hsCRP), and cytokines IL-6, IL-2, and TNF-alpha in CAD patients and controls.

RESULTS

IL-6 was significantly higher in CAD patents with medium and higher Cp IgA levels (35 vs. 10 and 32 vs. 4) compared to controls. Physiological features and baseline characteristics of CAD were significantly higher in IL-6 positive CAD patients. Additionally, in CAD patients IL-6 was significantly correlated with hsCRP (p<0.001, r=0.42).

CONCLUSIONS

Our results lead us to hypothesize the role of IL-6 in the pathogenesis of CAD, which may subsequently get accelerated through Cp infection.

Hypoxia enhances lysosomal TNF-alpha degradation in mouse peritoneal macrophages

Infection, simulated by lipopolysaccharide (LPS), is a potent stimulator of tumor necrosis factor-alpha (TNF-alpha) production, and hypoxia often synergizes with LPS to induce higher levels of the secreted cytokine. However, we show that in primary mouse peritoneal macrophages and in three mouse peritoneal macrophage cell lines (RAW 264.7, J774A.1, and PMJ-2R), hypoxia (O(2) < 0.3%) reduces the secretion of LPS-induced TNF-alpha (P < 0.01). In RAW 264.7 cells this reduction was not regulated transcriptionally as TNF-alpha mRNA levels remained unchanged. Rather, hypoxia and LPS reduced the intracellular levels of TNF-alpha by twofold (P < 0.01) by enhancing its degradation in the lysosomes and inhibiting its secretion via secretory lysosomes, as shown by confocal microscopy and verified by the use of the lysosome inhibitor Bafilomycin A1. In addition, although hypoxia did not change the accumulation of the soluble receptor TNF-RII, it increased its binding to the secreted TNF-alpha by twofold (P < 0.05). We suggest that these two posttranslational regulatory checkpoints coexist in hypoxia and may partially explain the reduced secretion and diminished biological activity of TNF-alpha in hypoxic peritoneal macrophages.

Leukocyte count predicts outcome after ischemic stroke: the Northern Manhattan Stroke Study

Leukocyte counts predict incident cardiovascular disease, but little data are available on the relationship of leukocyte count to outcome after ischemic stroke. We hypothesized that leukocyte count at the time of incident ischemic stroke is associated with prognosis. Patients with first ischemic stroke were prospectively followed for 5 years for the occurrence of recurrent stroke, myocardial infarction (MI), or death. Cox proportional hazard models were constructed to estimate hazard ratios and 95% confidence intervals (CIs) for the effect of leukocyte count on outcomes after adjusting for other risk factors. Ischemic stroke patients (n = 655) were evaluated (mean age, 69.7 +/- 12.7 years; 45% men; 51% Hispanic, 28% black, and 19% white). Seventy percent of samples were drawn within 24 hours of stroke. Mean leukocyte count was 9.1 +/- 4.7 x 10(9)/L. Leukocyte count was a significant independent predictor of the 30-day risk of recurrent stroke, MI, or death after adjusting for age, sex, race/ethnicity, other risk factors, and stroke severity (adjusted hazard ratio per unit increase in leukocyte count, 1.07; 95% CI, 1.00 to 1.13). Leukocyte count was also a significant independent predictor of outcome events over 5 years (adjusted hazard ratio per unit increase in leukocyte count, 1.04; 95% CI, 1.00 to 1.07). Our findings indicate that elevated leukocyte count at the time of ischemic stroke predicts future recurrent stroke, MI, or death. Acute infectious complications of stroke or underlying inflammation could account for this association.

Eggs modulate the inflammatory response to carbohydrate restricted diets in overweight men

Background

Carbohydrate restricted diets (CRD) consistently lower glucose and insulin levels and improve atherogenic dyslipidemia [decreasing triglycerides and increasing HDL cholesterol (HDL-C)]. We have previously shown that male subjects following a CRD experienced significant increases in HDL-C only if they were consuming a higher intake of cholesterol provided by eggs compared to those individuals who were taking lower concentrations of dietary cholesterol. Here, as a follow up of our previous study, we examined the effects of eggs (a source of both dietary cholesterol and lutein) on adiponectin, a marker of insulin sensitivity, and on inflammatory markers in the context of a CRD.

Methods

Twenty eight overweight men [body mass index (BMI) 26–37 kg/m²] aged 40–70 y consumed an ad libitum CRD (% energy from CHO:fat:protein = 17:57:26) for 12 wk. Subjects were matched by age and BMI and randomly assigned to consume eggs (EGG, n = 15) (640 mg additional cholesterol/day provided by eggs) or placebo (SUB, n = 13) (no additional dietary cholesterol). Fasting blood samples were drawn before and after the intervention to assess plasma lipids, insulin, adiponectin and markers of inflammation including C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1(VCAM-1).

Results

Body weight, percent total body fat and trunk fat were reduced for all subjects after 12 wk (P < 0.0001). Increases in adiponectin were also observed (P < 0.01). Subjects in the EGG group had a 21% increase in this adipokine compared to a 7% increase in the SUB group (P < 0.05). Plasma CRP was significantly decreased only in the EGG group (P < 0.05). MCP-1 levels were decreased for the SUB group (P < 0.001), but unchanged in the EGG group. VCAM-1, ICAM-1, TNF-α, and IL-8 were not modified by CRD or eggs.

Conclusion

A CRD with daily intake of eggs decreased plasma CRP and increased plasma adiponectin compared to a CRD without eggs. These findings indicate that eggs make a significant contribution to the anti-inflammatory effects of CRD, possibly due to the presence of cholesterol, which increases HDL-C and to the antioxidant lutein which modulates certain inflammatory responses.