Abstract 23: Identification of NCF4 as a Novel Regulator in Arterial Remodeling and Advanced Atherosclerosis

Arterial wall remodeling is a central multifactorial process in the development and progression of cardiovascular diseases. We employed an approach aimed at observing genetic variants associated with the progression of carotid intima-media thickness (cIMT) in order to identify novel pathways effecting vessel remodeling. This was achieved by conducting gene-centric analysis of 400,000 variants in 3,042 subjects with repeated cIMT measurements.

Rs16997464 on chr22 intergenic between neutrophil cytosolic factor-4 ( NCF4) and colony stimulating factor 2 receptor beta ( CSF2RB ) was associated with cIMT progression at array-wide significance (p <4.5x10 -7 ). The potential causative genes within this locus were investigated using a human vascular and non-vascular tissue biobank. Expression of 9 genes near rs16997464, were analyzed with the most significant association being with NCF4 in aortic adventitia. The effect of the variant on the function of the NCF4 gene product was further analyzed by comparing the oxidative burst capacity of neutrophils from subjects with different rs16997464 genotypes. We observed that neutrophils homozygous for the minor T allele, associated with slower cIMT progression, produced more extracellular ROS than neutrophils homozygous for the G allele, indicating a functional effect of rs16997464 on the NCF4 gene product p40 phox , a component of the NADPH oxidase 2 complex (NOX2).

In parallel, we investigated if the chr22 locus also influenced the cellular composition of the atherosclerotic plaque, by utilizing data from the Athero-Express Biobank. Here we found that the minor T allele associated with a higher smooth muscle cell (SMC) content in the plaque. Finally, using a partial ligation model in mice where ncf4 is mutated, resulting in a reduced but not absent NOX2-associated ROS formation, we observed a reduced neointima formation in the ncf4 -mutated strain compared with wild-type littermates.

Thus, this study identified rs16997464 in the NCF4-CSF2RB locus as a novel genetic determinant of cIMT progression, and provides evidence suggesting that NCF4 is involved in SMC proliferation and alteration of vessel wall pathophysiology.

Lipoprotein(a) and risk of sudden cardiac death in middle-aged Finnish men: A new prospective cohort study

BACKGROUND

Lipoprotein(a) [Lp(a)] is an established and independent risk factor for cardiovascular outcomes. However, the relationship of Lp(a) with risk of sudden cardiac death (SCD) is unknown. We aimed to assess the association of Lp(a) with risk of SCD in the Kuopio Ischemic Heart Disease prospective cohort study of 1881 men aged 42-61years at recruitment.

METHODS AND RESULTS

Plasma Lp(a) concentration was assessed at baseline and repeat measurements made several years apart. After a median follow-up of 24.7years, 141 SCDs were recorded. Hazard ratios (HRs) (95% confidence intervals [CI]) were assessed and were corrected for within-person variability in Lp(a) levels. The regression dilution ratio of loge Lp(a) adjusted for age was 0.84 (95% CI: 0.81-0.88). Lipoprotein(a) levels were log-linearly associated with risk of SCD. In analyses adjusted for established risk factors, the HR (95% CI) for SCD per 1 standard deviation (3.56-fold) higher baseline loge Lp(a) was 1.24 (1.05-1.47; P=0.013). This remained consistent on further adjustment for alcohol consumption, resting heart rate, lipids, and C-reactive protein 1.23 (1.04-1.46; P=0.018). HRs remained unchanged after accounting for incident coronary events and did not vary importantly in several relevant clinical subgroups. Adding Lp(a) to a SCD risk prediction model did not significantly improve risk discrimination beyond established risk factors, but improved the continuous net reclassification 30.2% (1.1 to 59.2%, P=0.042).

CONCLUSIONS

Available evidence shows a continuous and independent association between Lp(a) levels and risk of SCD. Further research is needed to replicate these findings.

Olive Oil Polyphenols Decrease LDL Concentrations and LDL Atherogenicity in Men in a Randomized Controlled Trial

BACKGROUND

Olive oil polyphenols have shown protective effects on cardiovascular risk factors. Their consumption decreased oxidative stress biomarkers and improved some features of the lipid profile. However, their effects on LDL concentrations in plasma and LDL atherogenicity have not yet been elucidated.

OBJECTIVE

Our objective was to assess whether the consumption of olive oil polyphenols could decrease LDL concentrations [measured as apolipoprotein B-100 (apo B-100) concentrations and the total number of LDL particles] and atherogenicity (the number of small LDL particles and LDL oxidizability) in humans.

METHODS

The study was a randomized, cross-over controlled trial in 25 healthy European men, aged 20-59 y, in the context of the EUROLIVE (Effect of Olive Oil Consumption on Oxidative Damage in European Populations) study. Volunteers ingested 25 mL/d raw low-polyphenol-content olive oil (LPCOO; 366 mg/kg) or high-polyphenol-content olive oil (HPCOO; 2.7 mg/kg) for 3 wk. Interventions were preceded by 2-wk washout periods. Effects of olive oil polyphenols on plasma LDL concentrations and atherogenicity were determined in the sample of 25 men. Effects on lipoprotein lipase (LPL) gene expression were assessed in another sample of 18 men from the EUROLIVE study.

RESULTS

Plasma apo B-100 concentrations and the number of total and small LDL particles decreased (mean ± SD: by 5.94% ± 16.6%, 11.9% ± 12.0%, and 15.3% ± 35.1%, respectively) from baseline after the HPCOO intervention. These changes differed significantly from those after the LPCOO intervention, which resulted in significant increases of 6.39% ± 16.6%, 4.73% ± 22.0%, and 13.6% ± 36.4% from baseline (P < 0.03). LDL oxidation lag time increased by 5.0% ± 10.3% from baseline after the HPCOO intervention, which was significantly different only relative to preintervention values (P = 0.038). LPL gene expression tended to increase by 26% from baseline after the HPCOO intervention (P = 0.08) and did not change after the LPCOO intervention.

CONCLUSION

The consumption of olive oil polyphenols decreased plasma LDL concentrations and LDL atherogenicity in healthy young men. This trial was registered at www.controlled-trials.com as ISRCTN09220811.

Olive Oil Polyphenols Enhance High-Density Lipoprotein Function in Humans

Objective—

Olive oil polyphenols have shown beneficial properties against cardiovascular risk factors. Their consumption has been associated with higher cholesterol content in high-density lipoproteins (HDL). However, data on polyphenol effects on HDL quality are scarce. We, therefore, assessed whether polyphenol-rich olive oil consumption could enhance the HDL main function, its cholesterol efflux capacity, and some of its quality-related properties, such HDL polyphenol content, size, and composition.

Approach and Results—

A randomized, crossover, controlled trial with 47 healthy European male volunteers was performed. Participants ingested 25 mL/d of polyphenol-poor (2.7 mg/kg) or polyphenol-rich (366 mg/kg) raw olive oil in 3-week intervention periods, preceded by 2-week washout periods. HDL cholesterol efflux capacity significantly improved after polyphenol-rich intervention versus the polyphenol-poor one (+3.05% and −2.34%, respectively; P =0.042). Incorporation of olive oil polyphenol biological metabolites to HDL, as well as large HDL (HDL 2 ) levels, was higher after the polyphenol-rich olive oil intervention, compared with the polyphenol-poor one. Small HDL (HDL 3 ) levels decreased, the HDL core became triglyceride-poor, and HDL fluidity increased after the polyphenol-rich intervention.

Conclusions—

Olive oil polyphenols promote the main HDL antiatherogenic function, its cholesterol efflux capacity. These polyphenols increased HDL size, promoted a greater HDL stability reflected as a triglyceride-poor core, and enhanced the HDL oxidative status, through an increase in the olive oil polyphenol metabolites content in the lipoprotein. Our results provide for the first time a first-level evidence of an enhancement in HDL function by polyphenol-rich olive oil.

Identification of the BCAR1-CFDP1-TMEM170A locus as a determinant of carotid intima-media thickness and coronary artery disease risk

BACKGROUND

Carotid intima-media thickness (cIMT) is a widely accepted marker of subclinical atherosclerosis. To date, large-scale investigations of genetic determinants of cIMT are sparse.

METHODS AND RESULTS

To identify cIMT-associated genes and genetic variants, a discovery analysis using the Illumina 200K CardioMetabochip was conducted in 3430 subjects with detailed ultrasonographic determinations of cIMT from the IMPROVE (Carotid Intima Media Thickness [IMT] and IMT-Progression as Predictors of Vascular Events in a High Risk European Population) study. Segment-specific IMT measurements of common carotid, bifurcation, and internal carotid arteries, and composite IMT variables considering the whole carotid tree (IMT(mean), IMT(max), and IMT(mean-max)), were analyzed. A replication stage investigating 42 single-nucleotide polymorphisms for association with common carotid IMT was undertaken in 5 independent European cohorts (total n=11,590). A locus on chromosome 16 (lead single-nucleotide polymorphism rs4888378, intronic in CFDP1) was associated with cIMT at significance levels passing multiple testing correction at both stages (array-wide significant discovery P=6.75 × 10(-7) for IMT(max); replication P=7.24×10(-6) for common cIMT; adjustments for sex, age, and population substructure where applicable; minor allele frequency 0.43 and 0.41, respectively). The protective minor allele was associated with lower carotid plaque score in a replication cohort (P=0.04, n=2120) and lower coronary artery disease risk in 2 case-control studies of subjects with European ancestry (odds ratio [95% confidence interval] 0.83 [0.77-0.90], P=6.53 × 10(-6), n=13 591; and 0.95 [0.92-0.98], P=1.83 × 10(-4), n=82 297, respectively). Queries of human biobank data sets revealed associations of rs4888378 with nearby gene expression in vascular tissues (n=126-138).

CONCLUSIONS

This study identified rs4888378 in the BCAR1-CFDP1-TMEM170A locus as a novel genetic determinant of cIMT and coronary artery disease risk in individuals of European descent.

A gene-centric study of common carotid artery remodelling

Background

Expansive remodelling is the process of compensatory arterial enlargement in response to atherosclerotic stimuli. The genetic determinants of this process are poorly characterized.

Methods

Genetic association analyses of inter-adventitial common carotid artery diameter (ICCAD) in the IMPROVE study (n = 3427) using the Illumina 200k Metabochip was performed. Single nucleotide polymorphisms (SNPs) that met array-wide significance were taken forward for analysis in three further studies (n = 5704), and tested for association with Abdominal Aortic Aneurysm (AAA).

Results

rs3768445 on Chromosome 1q24.3, in a cluster of protein coding genes (DNM3, PIGC, C1orf105) was associated with larger ICCAD in the IMPROVE study. For each copy of the rare allele carried, ICCAD was on average 0.13 mm greater (95% CI 0.08–0.18 mm, P = 8.2 × 10⁻⁸). A proxy SNP (rs4916251, R² = 0.99) did not, however, show association with ICCAD in three follow-up studies (P for replication = 0.29). There was evidence of interaction between carotid intima-media thickness (CIMT) and rs4916251 on ICCAD in two of the cohorts studies suggesting that it plays a role in the remodelling response to atherosclerosis. In meta-analysis of 5 case–control studies pooling data from 5007 cases and 43,630 controls, rs4916251 was associated with presence of AAA 1.10, 95% CI 1.03–1.17, p = 2.8 × 10⁻³, I² = 18.8, Q = 0.30). A proxy SNP, rs4916251 was also associated with increased expression of PIGC in aortic tissue, suggesting that this may the mechanism by which this locus affects vascular remodelling.

Conclusions

Common variation at 1q24.3 is associated with expansive vascular remodelling and risk of AAA. These findings support a hypothesis that pathways involved in systemic vascular remodelling play a role in AAA development.

LDL oxidative modification and carotid atherosclerosis: results of a multicenter study

OBJECTIVE

Serum LDL conjugated diene concentration is a marker of oxidative modification of LDL. We investigated the relationship between LDL conjugated dienes and cross-sectional subclinical atherosclerosis assessed by carotid IMT in high-risk subjects of a multicenter study.

METHODS

Serum LDL conjugated dienes and ultrasonographically assessed carotid intima-media thickness (IMT(mean), IMT(max) and IMT(mean-max)) were available for 553 subjects from Finland, France, Italy, the Netherlands, and Sweden.

RESULTS

In multivariate regression analysis, gender (p < 0.001), age (p < 0.001), systolic blood pressure (IMT(mean), p = 0.01; IMT(mean-max), p = 0.05) and serum LDL conjugated dienes (p = 0.02 for both IMT(mean) and IMT(mean-max)) were the strongest determinants of IMT variation, adjusted for study center, ultrasound videotape reader and serum LDL cholesterol. Pack-years of smoking, added into the regression model, did not destroy the significant association between increased serum LDL conjugated dienes and IMT. Ratio of LDL conjugated dienes to LDL particle cholesterol was higher in subjects of Northern recruiting centers than of Southern centers (r = 0.39, p < 0.0001).

CONCLUSIONS

There was a cross-sectional association between in vivo increased LDL oxidative modification and subclinical atherosclerosis after adjustment for traditional risk factors. The subjects in Northern countries of Europe had more oxidatively modified lipids per cholesterol in LDL particle than subjects in Southern countries.

Cross-sectional analysis of baseline data to identify the major determinants of carotid intima-media thickness in a European population: the IMPROVE study

AIMS

The 'IMPROVE study' was designed to investigate whether cross-sectional carotid artery intima-media thickness (IMT) and overall IMT progression are predictors of new vascular events in European individuals at high risk of cardiovascular diseases. This paper reports the results of the baseline analyses aimed at identifying the major determinants of increased carotid IMT (C-IMT).

METHODS AND RESULTS

IMPROVE is a prospective, multicentre, longitudinal, observational study. A total of 3711 subjects (age range 54-79 years) with at least three vascular risk factors (VRFs) were recruited in seven centres in Finland, France, Italy, the Netherlands, and Sweden. Collected variables included clinical, biochemical, genetic, socioeconomic, psychological, nutritional, and educational data, personal and family history of diseases, drug intake, and physical activity. By multiple linear regression analysis, C-IMT was positively associated with latitude, age, gender, pulse pressure, pack-years, and hypertension, and inversely with educational level (all P < 0.0001 for IMT(mean-max)). Latitude was the strongest independent determinant of C-IMT (partial r(2) for IMT(mean-max) = 0.109, P < 0.0001) and alone accounted for nearly half of the variation explained by the regression model (partial r(2) for IMT(mean-max) = 0.243, P < 0.0001). The geographical gradient for C-IMT paralleled the well-known north-to-south cardiovascular mortality gradient (r(2) for IMT(mean) = 0.96).

CONCLUSION

Latitude is an important determinant of C-IMT, which is not explained by between-country differences in established VRFs. Other unknown contributory mechanisms such as heritable, nutritional, or environmental factors may be important in the genesis of this geographical gradient.

Lycopene, lutein and beta-carotene as determinants of LDL conjugated dienes in serum

Oxidative modification of low-density lipoprotein (LDL) in the vascular endothelium is considered to be important in the development of early atherosclerosis. The aim of this study was to investigate the main determinants of serum LDL conjugated dienes in women (n=124) and men (n=225). We focused on the influence of fat-soluble vitamins and carotenoids on the concentration of conjugated dienes in LDL. In multivariate linear regression models, including age, body mass index, diastolic blood pressure, symptomatic ischaemic heart disease (IHD) or IHD history, statin medication, leukocytes and serum triglycerides as covariates, plasma lycopene (standardized beta=-0.33; P=0.002) and lutein (standardized beta=-0.22; P=0.027) concentrations were the strongest determinants of serum LDL conjugated dienes in women, whereas plasma beta-carotene (standardized beta=-0.23; P=0.002) was the most important factor in men. Furthermore, statin medication, diastolic blood pressure, age and serum triglycerides were significant determinants of LDL conjugated dienes. The regression model with lycopene contributed to 29% in women and 15% in men with beta-carotene of the variation of serum LDL conjugated dienes. Results of the present study suggest that plasma lycopene, lutein and beta-carotene are the most powerful antioxidants for explaining the content of in vivo oxidatively modified LDL in serum.

C18 hydroxy fatty acids as markers of lipid peroxidationex vivoandin vivo

Different C18 monohydroxy fatty acids (OHFAs) were evaluated for their usefulness as markers of plasma lipid peroxidation (unsaturated fatty acid oxidation) ex vivo and in vivo. First, plasma samples (n = 5) were exposed for 3 h to different radical fluxes ex vivo. The formation of OHFAs was assessed by using varying concentrations of Cu2+ ions and AAPH (2,2'-azobis(2-amidinopropane) hydrochloride) as radical flux initiators. Secondly, a cross-sectional study was carried out in 47 middle-aged men. In this study, plasma concentrations of different in vivo OHFAs were compared with other indices of lipid peroxidation. Under mild oxidation conditions (heparin plasma containing 4.2 or 8.3 mM AAPH), concentrations of all the measured OHFAs (8, 9, 10, 11, 12, 13, 15 and 16-OH acids) increased in an identical manner, but under highly oxidative conditions (heparin plasma containing 83 mM AAPH or 4.2 to 8.3 mM CuSO4) mainly 9 and 13-OHFAs were formed. In the cross-sectional study, plasma 11 and 13-OHFA levels were associated statistically significantly with plasma free F2alpha-isoprostanes, recognized index of in vivo lipid peroxidation (r = 0.305, p = 0.037 and r = 0.308, p = 0.035, respectively). In addition, 16-OHFA levels correlated with the ratio of electronegatively charged LDL to total LDL (r = 0.335, p = 0.021). With respect to the other OHFAs, 15-OHFA had no correlation with either other OHFAs or the reference substances used. In addition, occasionally there were contamination problems in the assessment of 12-OHFA. It is concluded that all of the measured C18 OHFAs can be used as indicators of plasma lipid peroxidation under mild oxidation conditions, though the 12 and 15-OHFAs may need to be used with some caution. Under high oxidation conditions, 9-and 13-OHFAs seem to be the most useful indices because of their high formation capacity.

Body iron is a contributor to oxidative damage of DNA

The transition metal iron is catalytically highly active in vitro, and not surprisingly, body iron has been suggested to promote oxidative stress in vivo. In the current analysis we studied the association of serum ferritin concentration and serum soluble transferrin receptor concentration with daily urinary 8-hydroxydeoxyguanosine excretion, a marker of oxidative stress, in 48 mildly dyslipidemic men in East Finland. In multivariate linear regression analyses allowing for age, smoking, body mass index and physical exercise, serum ferritin concentration predicted the excretion rate at B = 0.17 (95% CI 0.08-0.26, P = 0.001), and serum soluble transferrin receptor to ferritin concentration ratio (TfR/ferritin) predicted the excretion rate at B = - 0.13 (95% CI - 0.21 to - 0.05, P = 0.002). Our data suggest that body iron contributes to excess oxidative stress already at non-iron overload concentrations in these subjects.

Systematically missing confounders in individual participant data meta-analysis of observational cohort studies

One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154 012 participants in 31 cohorts.† Copyright © 2009 John Wiley & Sons, Ltd.

Serum lycopene and the risk of cancer: the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) study

PURPOSE

Lycopene is thought to decrease the risk of cancers, although previous epidemiologic studies have produced inconsistent results. The aim of the present study was to evaluate the protective effect of lycopene against the risk of cancer.

METHODS

The study population consisted of 997 middle-aged Finnish men in the Kuopio Ischaemic Heart Disease Risk Factor (KIHD) cohort. During the mean follow-up time of 12.6 years, a total of 141 cancer cases appeared, of which 55 were prostate cancers. The association between the serum concentrations of lycopene and the risk of cancer was studied using the Cox proportional hazard models.

RESULTS

An inverse association was observed between serum lycopene and overall cancer incidence. The adjusted risk ratio (RR) in the highest tertile of serum lycopene was 0.55 (95% confidence interval [CI], 0.34-0.89; p=0.015) compared with the lowest serum lycopene group. No association was observed between the lycopene concentrations and a prostate cancer risk. RR for other cancers was 0.43 (95% CI, 0.23-0.79; p=0.007).

CONCLUSIONS

These findings suggest that in middle-aged men, the higher circulating concentrations of lycopene may contribute to the lower risk of cancer, with the exception of prostate cancer.

Suitability of Smopex-102 cation-exchange fiber for analytical purposes and drug monitoring

The present study aimed to evaluate the suitability of Smopex-102 cation-exchange fiber for the separation of acidic and basic model drugs from biological fluids (e.g. serum) prior to chromatographic analysis. In addition, the interactions of the drugs with the fiber were studied. The study found that basic antidepressant model drugs bound to a considerably greater extent than acidic drugs to poly(acrylic acid) (PAA) grafted Smopex-102 cation-exchange fiber from 25 mM HEPES buffer (pH 7.0) and spiked serum. Drug binding from serum decreased except for acidic drugs due to drug distribution between serum proteins and cation-exchange fiber. Electrostatic interactions were possibly the most important factors affecting drug binding to the fiber. Basic drugs were released most effectively from the fiber by using acetic acid (mean released amount 123.7 +/- 36.3% and mean absolute recovery 95.4 +/- 23.8%). Results demonstrated that the cation-exchange fiber evaluated might be a potential material for separating basic drugs from protein-free and proteinaceous (e.g. serum) liquid solutions for subsequent monitoring and evaluation. However, the drug release solution and release time must be optimized more precisely in order to validate described sample preparation method for each basic drug.

Hopelessness — novel facet of the metabolic syndrome in men

Aims: Recent studies have shown that lack of hope is linked to cardiovascular morbidity and mortality. Little is known, however, about the relationship of hopelessness and the metabolic syndrome. The aim of this study is to examine the association of hopelessness and the metabolic syndrome. Methods: This cross-sectional study examines the relationship between hopelessness and the metabolic syndrome as defined by the National Cholesterol Education Program in a population-based cohort of 1743 non-diabetic men aged 42, 48, 54 and 60 years old at baseline (1984—89). Hopelessness was measured by one's expectations about the future and reaching goals. Results: In simple age-adjusted univariate analyses the prevalence of the metabolic syndrome, many of its components and other cardiovascular risk factors were more common in men with higher levels of hopelessness. In a logistic regression model adjusted for age, smoking, alcohol consumption, cardiovascular disease, adult socioeconomic status and physical activity, men in the highest third were 2.1 (95% CI 1.3—3.2) times more likely to have the metabolic syndrome than those in the lowest third. After further adjusting for body mass index and elevated depressive symptoms the respective figures were 1.9 (95% CI 1.2—3.1) and 2.1 (95% CI 1.4—3.4). Conclusions: Hopelessness was strongly associated with the metabolic syndrome in these middle-aged men, independent of other depressive symptoms and traditional cardiovascular risk factors. These findings suggest that hopelessness is very closely related to the metabolic syndrome. Therefore lifestyle management of the metabolic syndrome should also take into account patients' expectations more thoroughly than hitherto acknowledged.

Apolipoprotein E polymorphism is associated with both carotid and coronary atherosclerosis in patients with coronary artery disease

BACKGROUND AND AIMS

Apolipoprotein E (apoE) polymorphism plays a significant role in the development of atherosclerosis and cardiovascular disease. Therefore, the aim of the present study was to examine the association between apoE polymorphism and carotid intima-media thickness (IMT), and severity and extent of coronary artery disease (CAD).

METHODS AND RESULTS

B-mode ultrasound and quantitative coronary angiography (QCA) were used to assess carotid, and coronary artery atherosclerosis in 91 patients with clinically suspected CAD referred for cardiac catheterization. Two apoE phenotype groups were defined: apoE3 (E3/E3) and apoE4 (including E4/E3, E4/E4 phenotypes). Maximum IMT was higher in the apoE4 group than in the apoE3 group (p=0.022). The global atheroma burden index was similarly higher in the apoE4 group than in the apoE3 group (p=0.033). ApoE4 subjects had higher levels of apolipoprotein B (apoB) (p=0.008), triglycerides (p=0.006), remnant lipoprotein-cholesterol (RLP-C) (p=0.023), and lipoprotein(a) [(Lp(a)] (p=0.041) than apoE3 subjects. The mean LDL particle size was smaller in the apoE4 group than in the apoE3 group (p=0.041).

CONCLUSIONS

ApoE polymorphism was associated with both carotid and coronary atherosclerosis. Patients with the apoE4 isoform had an increased carotid IMT and a more severe and extensive CAD than patients with the apoE3 isoform.

Dyslipidaemia as a predictor of hypertension in middle-aged men

AIMS

Dyslipidaemia and hypertension are features of the metabolic syndrome, but the role of dyslipidaemia in the development of hypertension is less clear. We assessed the association of dyslipidaemia with incident hypertension during a 7-year follow-up in a population-based cohort of middle-aged men without hypertension at baseline.

METHODS AND RESULTS

In all, 88 of 311 men developed hypertension during the follow-up. A 1-SD increment in triglyceride concentrations was associated with a 1.6-fold [95% CI(confidence interval) 1.2-2.3] increased risk of developing hypertension, independently of features related to the metabolic syndrome. In separate multivariable models, the triglyceride content of high-density lipoprotein (HDL) cholesterol and apolipoprotein B concentrations were also associated with new-onset hypertension. In a stepwise backwards logistic regression model, concentrations of low-density lipoprotein (LDL) cholesterol [odds ratio (OR) 1.3, 95% CI 1.0-1.7 for a 1-SD change] and triglyceride content of HDL cholesterol (OR) 1.5, 95% CI 1.1-1.9) were positively associated with incident hypertension, whereas HDL concentrations (OR 0.7, 95% CI 0.5-0.9) seemed protective. In factor analyses, elevated triglyceride levels and related disturbances in lipid and cholesterol metabolism were associated with new-onset hypertension.

CONCLUSION

Dyslipidaemia characteristic of the metabolic syndrome predicts the development of hypertension during a 7-year follow-up of eastern Finnish men, independently of features related to insulin resistance. The recognition of dyslipidaemia and initiation of lifestyle treatment even in the absence of hypertension is likely to reduce the long-term burden of cardiovascular disease.

The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases

Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.

Isolation of drugs from biological fluids by using pH sensitive poly(acrylic acid) grafted poly(vinylidene fluoride) polymer membrane in vitro

Isolation of acidic and basic model drugs by using pH sensitive poly(acrylic acid) grafted poly(vinylidene fluoride) (PAA-PVDF) cation-exchange membrane from biological fluids was reported. Effects of drug charge and lipophilicity on adsorption were also investigated. In the present study, basic model drugs adsorbed to a considerably greater extent onto the membrane than acidic drugs. Albumin was not adsorbed onto the membrane. Results of our study exposed, that electrostatic interactions between positively charged basic drug and negatively charged PVDF-PAA membrane were the most important factor affecting drug adsorption onto the membrane. Adsorption of acidic and basic drugs onto the PVDF-PAA membrane was not related to drug lipophilicity. The results of present study demonstrated that basic drugs adsorbed extensively onto the membrane, but albumin did not, proposing that PAA-PVDF membrane may be suitable for isolating basic drugs from proteinaceous biological fluids (i.e. serum) for subsequent monitoring and evaluation.

Effects of astaxanthin supplementation on lipid peroxidation

Astaxanthin, the main carotenoid pigment in aquatic animals, has greater antioxidant activity in vitro (protecting against lipid peroxidation) and a more polar configuration than other carotenoids. We investigated the effect of three-month astaxanthin supplementation on lipid peroxidation in healthy non-smoking Finnish men, aged 19-33 years by using a randomized double-blind study design. Also absorption of astaxanthin from capsules into bloodstream and its safety were evaluated. The intervention group received two 4-mg astaxanthin (Astaxin) capsules daily, and the control group two identical-looking placebo capsules. Astaxanthin supplementation elevated plasma astaxanthin levels to 0.032 pmol/L (p < 0.001 for the change compared with the placebo group). We observed that levels of plasma 12- and 15-hydroxy fatty acids were reduced statistically significantly in the astaxanthin group (p = 0.048 and p = 0.047 respectively) during supplementation, but not in the placebo group and the change of 15-hydroxy fatty acid was almost significantly greater (p = 0.056) in the astaxanthin group, as compared with the placebo group. The present study suggests that intestinal absorption of astaxanthin delivered as capsules is adequate, and well tolerated. Supplementation with astaxanthin may decrease in vivo oxidation of fatty acids in healthy men.

Adsorption of drugs onto a pH responsive poly(N,N-dimethyl aminoethyl methacrylate) grafted anion-exchange membrane in vitro

The influence of charge and lipophilicity of acidic and basic model drugs on their adsorption onto poly(N,N-dimethyl aminoethyl methacrylic acid) grafted poly(vinylidene fluoride) (DMAEMA-PVDF) membranes was evaluated. The effect of serum proteins (albumin, IgG) and hormones (cortisol, free thyroxine (T(4)F) and thyrotropin (TSH)) on drug adsorption was also studied. Acidic model drugs (antiepileptics and benzodiazepies) adsorbed to a greater extent onto the membrane from Hepes buffer at ionic strength of 25mM and pH 7.0 than basic drugs (antidepressants) did. Adsorption of acidic model drugs was based on electrostatic interactions between positively charged tertiary amino groups of DMAEMA side-chain and acidic negatively charged drug. Albumin diminished the adsorption of drugs from serum onto the membrane. Lipophilicity was related to the adsorption of acidic model drugs from serum onto the membrane. The degree of grafting had the greatest effect on adsorption of lipophilic drugs, but no influence was observed on adsorption of hydrophilic drugs. The present results showed that acidic drugs and albumin adsorbed onto the membrane, which suggests that the PVDF-DMAEMA membrane may be suitable for separating acidic drugs from protein-free substances for subsequent monitoring and evaluation.

Effect of olive oils on biomarkers of oxidative DNA stress in Northern and Southern Europeans

High consumption of olive oil in the Mediterranean diet has been suggested to protect DNA against oxidative damage and to reduce cancer incidence. We investigated the impact of the phenolic compounds in olive oil, and the oil proper, on DNA and RNA oxidation in North, Central, and South European populations. In a multicenter, double-blind, randomized, controlled crossover intervention trial, the effect of olive oil phenolic content on urinary oxidation products of guanine (8-oxo-guanine, 8-oxo-guanosine and 8-oxo-deoxyguanosine) was investigated. Twenty-five milliliters of three olive oils with low, medium, and high phenolic content were administered to healthy males (n=182) daily for 3 wk. At study baseline the urinary excretion of 8-oxo-guanosine (RNA oxidation) and 8-oxo-deoxyguanosine (DNA oxidation) was higher in the Northern regions of Europe compared with Central and Southern European regions (P=0.035). Urinary excretion of the 8 hydroxylated forms of guanine, guanosine, deoxyguanosine and their nonoxidized forms were not different when comparing olive oils with low, medium, and high phenolic content given for 2 wk. Testing the effect of oil from urinary 8-oxo-deoxyguanosine changes from baseline to post-treatment showed a reduction of DNA oxidation by 13% (P=0.008). These findings support the idea that ingestion of olive oil is beneficial and can reduce the rate of oxidation of DNA. This effect is not due to the phenolic content in the olive oil. The higher DNA and RNA oxidation in Northern European regions compared with that in Central and Southern regions supports the contention that olive oil consumption may explain some of the North-South differences in cancer incidences in Europe.

The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial

BACKGROUND

Virgin olive oils are richer in phenolic content than refined olive oil. Small, randomized, crossover, controlled trials on the antioxidant effect of phenolic compounds from real-life daily doses of olive oil in humans have yielded conflicting results. Little information is available on the effect of the phenolic compounds of olive oil on plasma lipid levels. No international study with a large sample size has been done.

OBJECTIVE

To evaluate whether the phenolic content of olive oil further benefits plasma lipid levels and lipid oxidative damage compared with monounsaturated acid content.

DESIGN

Randomized, crossover, controlled trial.

SETTING

6 research centers from 5 European countries.

PARTICIPANTS

200 healthy male volunteers.

MEASUREMENTS

Glucose levels, plasma lipid levels, oxidative damage to lipid levels, and endogenous and exogenous antioxidants at baseline and before and after each intervention.

INTERVENTION

In a crossover study, participants were randomly assigned to 3 sequences of daily administration of 25 mL of 3 olive oils. Olive oils had low (2.7 mg/kg of olive oil), medium (164 mg/kg), or high (366 mg/kg) phenolic content but were otherwise similar. Intervention periods were 3 weeks preceded by 2-week washout periods.

RESULTS

A linear increase in high-density lipoprotein (HDL) cholesterol levels was observed for low-, medium-, and high-polyphenol olive oil: mean change, 0.025 mmol/L (95% CI, 0.003 to 0.05 mmol/L), 0.032 mmol/L (CI, 0.005 to 0.05 mmol/L), and 0.045 mmol/L (CI, 0.02 to 0.06 mmol/L), respectively. Total cholesterol-HDL cholesterol ratio decreased linearly with the phenolic content of the olive oil. Triglyceride levels decreased by an average of 0.05 mmol/L for all olive oils. Oxidative stress markers decreased linearly with increasing phenolic content. Mean changes for oxidized low-density lipoprotein levels were 1.21 U/L (CI, -0.8 to 3.6 U/L), -1.48 U/L (-3.6 to 0.6 U/L), and -3.21 U/L (-5.1 to -0.8 U/L) for the low-, medium-, and high-polyphenol olive oil, respectively.

LIMITATIONS

The olive oil may have interacted with other dietary components, participants' dietary intake was self-reported, and the intervention periods were short.

CONCLUSIONS

Olive oil is more than a monounsaturated fat. Its phenolic content can also provide benefits for plasma lipid levels and oxidative damage. International Standard Randomised Controlled Trial number: ISRCTN09220811.

Consumption of juice fortified with oregano extract markedly increases excretion of phenolic acids but lacks short- and long-term effects on lipid peroxidation in healthy nonsmoking men

Oregano has been shown to possess antioxidant capacity in various in vitro models and has thus been suggested to be potentially beneficial to human health, but studies in humans are lacking. The aim of this study was to investigate the bioavailability and the effects of Origanum vulgare extract supplementation on serum lipids and lipid peroxidation in healthy nonsmoking men. A four-week double-blinded supplementation trial was concluded in which volunteers (n = 45) were randomized to consume daily mango-orange juice (placebo), mango-orange juice enriched with 300 mg/d total phenolic compounds from oregano extract, or mango-orange juice enriched with 600 mg/d total phenolic compounds from oregano extract. The excretion of phenolic compounds was markedly increased in the higher phenolic group as compared to the placebo group, but no significant changes were observed in the safety parameters, serum lipids, or biomarkers of lipid peroxidation.

Plasma N-terminal fragments of natriuretic propeptides predict the risk of cardiovascular events and mortality in middle-aged men

AIMS

The prognostic significance of N-terminal pro-A-type (NT-proANP) and pro-B-type natriuretic peptides (NT-proBNP) is not well documented in population-based prospective studies. We, therefore, studied if both NT-proANP and NT-proBNP are predictive for overall death, cardiovascular events, and atrial fibrillation (AF) among middle-aged men without heart failure or AF at baseline.

METHODS AND RESULTS

Plasma NT-proANP and NT-proBNP were measured in a representative population-based sample of 905 men (age 46-65 years) from eastern Finland. There were 110 deaths [58 cardiovascular and 40 coronary heart disease (CHD)] and 59 cases of AF during a follow-up of 10 years. The multivariable adjusted risk for overall was 1.35-fold (95% CI 1.15-1.57) and 1.52-fold (95% CI 1.21-1.91) for CHD death for each SD (160.8 pmol/L) increment in NT-proANP. The respective risks were 1.26-fold (95% CI 1.12-1.42) and 1.44-fold (95% CI 1.22-1.60) for each SD (58.9 pmol/L) increment in NT-proBNP. The adjusted risks for future AF were 1.46 (P<0.001) and 1.72-fold (P<0.001) for each SD increment in NT-proANP and NT-proBNP, respectively.

CONCLUSION

The main finding of the present study is that NT-proANP and NT-proBNP are strong predictors of death from cardiovascular and other causes including AF. These natriuretic peptides add to the prognostic value of conventional risk factors and provide a non-invasive measure for identifying men with high risk of death and its co-morbidities.

Metabolic Syndrome and the Risk of Stroke in Middle-Aged Men

BACKGROUND AND PURPOSE

The metabolic syndrome, a clustering of disturbed glucose and insulin metabolism, obesity and abdominal fat distribution, dyslipidemia, and hypertension is associated with cardiovascular diseases. The aim of this study was to examine the relationship of metabolic syndrome, as defined by National Cholesterol Education Program (NCEP) and World Health Organization (WHO) criteria, with the risk for stroke.

METHODS

Population-based cohort study with an average follow-up of 14.3 years from eastern Finland. A total of 1131 men with no history of cardiovascular disease and diabetes at baseline participated. Sixty-five strokes occurred, of which 47 were ischemic strokes.

RESULTS

Men with the metabolic syndrome as defined by the NCEP criteria had a 2.05-fold (95% CI, 1.03 to 4.11; P=0.042) risk for all strokes and 2.41-fold (95% CI, 1.12 to 5.32; P=0.025) risk for ischemic stroke, after adjusting for socioeconomic status, smoking, alcohol, and family history of coronary heart disease. Additional adjustment for ischemic changes during exercise test, serum low-density lipoprotein cholesterol, plasma fibrinogen, energy intake for saturated fats, energy expenditure of leisure time physical activity, and white blood cell count, the results remained significant. The risk ratios among men with metabolic syndrome as defined by the WHO criteria were 1.82 (95% CI, 1.01 to 3.26; P=0.046) for all strokes and 2.16 (95% CI, 1.11 to 4.19; P=0.022) for ischemic stroke. After further adjustment, the respective risks were 2.08 (95% CI, 1.12 to 3.87; P=0.020) and 2.47 (95% CI, 1.21 to 5.07; P=0.013).

CONCLUSIONS

The risk of any stroke is increased in men with metabolic syndrome, in the absence of stroke, diabetes and cardiovascular disease at baseline. Prevention of the metabolic syndrome presents a great challenge for clinicians with respect to stroke.

Association of carotid intima-media thickness with angiographic severity and extent of coronary artery disease

The present study examined the association between carotid intima-media thickness (IMT) and severity and extent of coronary artery disease (CAD). B-mode ultrasound and quantitative coronary angiography were used to assess carotid and coronary artery atherosclerosis in 108 patients with known or suspected CAD who had been referred for cardiac catheterization. Maximum and mean IMT values of carotid arteries were measured and expressed as mean aggregate values. To evaluate anatomic severity and extent of CAD, several quantitative coronary angiographically derived parameters were incorporated into indexes. These quantitative coronary angiographic measurements reflected CAD severity, extent, and overall "atheroma burden" and were calculated for the entire coronary tree and separately for different coronary segments (i.e., left main, proximal, mid, and distal segments). Maximum and mean IMT values were significantly correlated with CAD severity (p = 0.004 and 0.005, respectively), extent (p = 0.022 and 0.016, respectively), and atheroma burden (p = 0.008 for the 2 values). Further, carotid IMT was correlated with quantitative angiographic indexes for mid and distal segments but not with the proximal segments of coronary vessels. In conclusion, our study shows an association between carotid IMT and severity and extent of CAD as assessed by quantitative coronary angiography. Carotid IMT seems to be a weaker predictor of coronary atherosclerosis in the proximal parts of the coronary tree than in the mid and distal parts.

Comparison of HPLC method and commercial ELISA assay for asymmetric dimethylarginine (ADMA) determination in human serum

The performance of a new ELISA assay kit (DLD Diagnostika GmbH, Hamburg, Germany) for the determination of asymmetric dimethylarginine (ADMA) was evaluated against a reversed phase HPLC method. ADMA concentrations of 55 serum samples were measured with both methods. The intra-assay CV for ADMA-ELISA was 19% (n=10). Inter-assay CVs for ADMA-ELISA were 9% for kit control 1 (0.410+/-0.037 microM) and 14% for kit control 2 (1.174+/-0.165 microM). The intra- and inter-assay CVs for HPLC assay for ADMA were 2.5% (0.586+/-0.015 microM) and 4.2% (0.664+/-0.028 microM), respectively. There was no correlation between these two methods (R(2)=0.0972). The effect of storage conditions of the samples on ADMA concentrations was investigated by HPLC. ADMA concentration was stable after four freezing and thawing cycles. Overall, the HPLC method offered better sensitivity, selectivity and, very importantly, simultaneous determination of ADMA, SDMA, l-homoarginine and l-arginine.

Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis

CONTEXT

Plasma fibrinogen levels may be associated with the risk of coronary heart disease (CHD) and stroke.

OBJECTIVE

To assess the relationships of fibrinogen levels with risk of major vascular and with risk of nonvascular outcomes based on individual participant data.

DATA SOURCES

Relevant studies were identified by computer-assisted searches, hand searches of reference lists, and personal communication with relevant investigators.

STUDY SELECTION

All identified prospective studies were included with information available on baseline fibrinogen levels and details of subsequent major vascular morbidity and/or cause-specific mortality during at least 1 year of follow-up. Studies were excluded if they recruited participants on the basis of having had a previous history of cardiovascular disease; participants with known preexisting CHD or stroke were excluded.

DATA EXTRACTION

Individual records were provided on each of 154,211 participants in 31 prospective studies. During 1.38 million person-years of follow-up, there were 6944 first nonfatal myocardial infarctions or stroke events and 13,210 deaths. Cause-specific mortality was generally available. Analyses involved proportional hazards modeling with adjustment for confounding by known cardiovascular risk factors and for regression dilution bias.

DATA SYNTHESIS

Within each age group considered (40-59, 60-69, and > or =70 years), there was an approximately log-linear association with usual fibrinogen level for the risk of any CHD, any stroke, other vascular (eg, non-CHD, nonstroke) mortality, and nonvascular mortality. There was no evidence of a threshold within the range of usual fibrinogen level studied at any age. The age- and sex- adjusted hazard ratio per 1-g/L increase in usual fibrinogen level for CHD was 2.42 (95% confidence interval [CI], 2.24-2.60); stroke, 2.06 (95% CI, 1.83-2.33); other vascular mortality, 2.76 (95% CI, 2.28-3.35); and nonvascular mortality, 2.03 (95% CI, 1.90-2.18). The hazard ratios for CHD and stroke were reduced to about 1.8 after further adjustment for measured values of several established vascular risk factors. In a subset of 7011 participants with available C-reactive protein values, the findings for CHD were essentially unchanged following additional adjustment for C-reactive protein. The associations of fibrinogen level with CHD or stroke did not differ substantially according to sex, smoking, blood pressure, blood lipid levels, or several features of study design.

CONCLUSIONS

In this large individual participant meta-analysis, moderately strong associations were found between usual plasma fibrinogen level and the risks of CHD, stroke, other vascular mortality, and nonvascular mortality in a wide range of circumstances in healthy middle-aged adults. Assessment of any causal relevance of elevated fibrinogen levels to disease requires additional research.

Polyphenol-rich phloem enhances the resistance of total serum lipids to oxidation in men

In humans, polyphenol supplementation studies have resulted in inconsistent findings in lipid peroxidation. Our aim was to investigate the effects of a 4-week consumption of polyphenol-rich phloem on serum lipids and lipid peroxidation in the hydrophilic fraction of serum and on isolated lipoproteins. We conducted a randomized double-blind supplementation study consisting of 75 nonsmoking hypercholesterolemic men. Participants consumed 70 g daily of either rye bread (placebo) or phloem-fortified rye bread containing 31 mg (low polyphenol, LP) or 62 mg (high polyphenol, HP) of catechins. The ex vivo susceptibility of total serum lipids and VLDL and LDL to oxidation after copper induction was measured as a lag time to the maximal oxidation rate at the baseline and after the supplementation. In the HP group, an increase in the oxidation resistance of total serum lipids was observed (11.4%), while no effect was seen in the LP group (-0.8%) or in the placebo group (-1.0%) (p = 0.007). No differences were observed in the oxidation resistance of VLDL and LDL between the study groups. The phloem also increased in vitro oxidation resistance of serum lipids and radical scavenging activity (DPPH.) in a dose-dependent manner. Our results suggest that polyphenols may inhibit lipid peroxidation in the hydrophilic fraction of serum.

C-reactive protein in the prediction of cardiovascular and overall mortality in middle-aged men: a population-based cohort study

AIMS

Cut-offs for C-reactive protein concentrations have been recommended for risk stratification, but little is known about how these cut-offs predict cardiovascular risk in population-based cohorts. We therefore assessed the association of C-reactive protein levels with cardiovascular mortality in a population-based cohort of 2321 middle-aged men stratified by the presence of cardiovascular disease (CVD) at baseline.

METHODS AND RESULTS

C-reactive protein concentrations were categorized according to current recommendations (1 and 3 mg/L). During the 15 year follow-up, 77 men without CVD and 121 men with CVD at baseline died of CVD. In men without CVD at baseline (n=1476), age-adjusted cardiovascular mortality was 4.1-fold higher (95% CI 2.1-8.2) for C-reactive protein levels between 3.0 and 9.9 mg/L at baseline than for C-reactive protein levels <1.0 mg/L. In men with CVD at baseline (n=845), the corresponding age-adjusted cardiovascular mortality was 3.3-fold higher (95% CI 2.0-5.3). Adjustment for conventional CVD risk factors attenuated the risk somewhat. Further adjustment for dietary and lifestyle factors and factors related to insulin resistance did not affect the association. Classification of C-reactive protein by tertiles gave qualitatively similar results, but identified twice as many men at high risk. C-reactive protein levels also predicted overall mortality.

CONCLUSION

Currently, recommended cut-offs for C-reactive protein levels identify men at risk for cardiovascular and overall death independently of conventional and other risk factors in a population-based sample of middle-aged men with and without CVD at baseline. Lower cut-offs may better identify men at high risk for cardiovascular death, but improvement of current recommendations will require standardization of C-reactive protein assays.

Prediction of cardiovascular mortality in middle-aged men by dietary and serum linoleic and polyunsaturated fatty acids

BACKGROUND

Substitution of dietary polyunsaturated for saturated fat has long been recommended for the primary prevention of cardiovascular disease (CVD), but only a few prospective cohort studies have provided support for this advice.

METHODS

We assessed the association of dietary linoleic and total polyunsaturated fatty acid (PUFA) intake with cardiovascular and overall mortality in a population-based cohort of 1551 middle-aged men. Dietary fat composition was estimated with a 4-day food record and serum fatty acid composition.

RESULTS

During the 15-year follow-up, 78 men died of CVD and 225 of any cause. Total fat intake was not related to CVD or overall mortality. Men with an energy-adjusted dietary intake of linoleic acid (relative risk [RR] 0.39; 95% confidence interval [CI], 0.21-0.71) and PUFA (RR, 0.38; 95% CI, 0.20-0.70) in the upper third were less likely to die of CVD than men with intake in the lower third after adjustment for age. Multivariate adjustment weakened the association somewhat. Mortality from CVD was also lower for men with proportions of serum esterified linoleic acid (RR, 0.42; 95% CI, 0.21-0.80) and PUFA (RR, 0.25; 95% CI, 0.12-0.50) in the upper vs lower third, with some attenuation in multivariate analyses. Serum and to a lesser extent dietary linoleic acid and PUFA were also inversely associated with overall mortality.

CONCLUSIONS

Dietary polyunsaturated and more specifically linoleic fatty acid intake may have a substantial cardioprotective benefit that is also reflected in overall mortality. Dietary fat quality seems more important than fat quantity in the reduction of cardiovascular mortality in men.

The effects of coffee consumption on lipid peroxidation and plasma total homocysteine concentrations: a clinical trial

Despite extensive research, the cardiovascular effects of coffee consumption in humans remain controversial. Our aim was to investigate the excretion of coffee phenols and the effects of filtered coffee consumption on oxidative stress and plasma homocysteine (tHcy) concentration in humans. The study consisted of a multiple-dose clinical supplementation trial and a single-dose study. In the long-term trial, 43 healthy nonsmoking men optionally consumed daily either no coffee, 3 cups (450 mL), or 6 cups (900 mL) of filtered coffee for 3 weeks, while in the short-term study 35 subjects consumed a single dose of 0, 1 (150 mL), or 2 cups (300 mL) of coffee. Long-term consumption of coffee increased the urinary excretion of caffeic and ferulic acid. The change in the total excretion of phenolic acids in 3 and 6 cups groups represented 3.8 and 2.5% of the amount ingested daily. Plasma tHcy concentrations increased nonsignificantly, but the consumption of coffee had neither short-nor long-term effects on lipid peroxidation or the activity of measured antioxidant enzymes. In conclusion, the consumption of filtered coffee does not have any detectable effects on lipid peroxidation in healthy nonsmoking men. The effect of coffee consumption on tHcy concentrations needs further investigation.

Serum antibody levels to Actinobacillus actinomycetemcomitans predict the risk for coronary heart disease

OBJECTIVE

The association between serum antibody levels to major periodontal pathogens and coronary heart disease (CHD) was analyzed in a prospective population-based study.

METHODS AND RESULTS

The population comprised 1023 men (aged 46 to 64 years) in the Kuopio Ischemic Heart Disease Study. The subjects with CHD at baseline (n=113) were more often seropositive for Porphyromonas gingivalis IgA (38.9% versus 28.5%, P=0.021) and IgG (60.2% versus 46.7%, P=0.007) than those without CHD. During the 10-year follow-up, 109 men free from CHD at baseline experienced an acute myocardial infarction or CHD death. The men with an end point were more often seropositive for Actinobacillus actinomycetemcomitans IgA (15.5% versus 10.2%, P=0.019) than those who remained healthy. In the highest tertile of A. actinomycetemcomitans IgA-antibodies compared with the lowest one, the relative risk (RR) for an end point adjusted for CHD risk factors was 2.0 (95% confidence interval [CI], 1.2 to 3.3). In the Porphyromonas gingivalis IgA-antibody tertiles, the highest RR of 2.1 (1.3 to 3.4) was observed in the second tertile. All antibody levels correlated positively with the carotid artery intima-media thickness.

CONCLUSIONS

High-serum antibody levels to major periodontal pathogens are associated with subclinical, prevalent, and future incidence of CHD. Periodontal pathogens or host response against them may contribute to the pathogenesis of CHD.

The metabolic syndrome and smoking in relation to hypogonadism in middle-aged men: a prospective cohort study

In men, hypoandrogenism is associated with features of the metabolic syndrome. It is not known whether men with the metabolic syndrome are at a higher risk of developing hypogonadism. We therefore assessed whether the metabolic syndrome predicts development of hypogonadism 11 yr later in 651 middle-aged Finnish men participating in a population-based cohort study. Men with the metabolic syndrome at baseline as defined by the World Health Organization (n = 114, 20%) had a 2.6-fold increased risk of developing hypogonadism as defined by total testosterone levels less than 11 nmol/liter at the 11-yr follow-up independent of age, smoking, and other potential confounders. Further adjustment for body mass index (OR, 2.0; 95% CI, 1.1-3.8) or baseline total testosterone levels (OR, 1.9; 95% CI, 1.0-3.4) attenuated the association. The association of the metabolic syndrome with hypogonadism as defined by calculated free testosterone levels less than 225 pmol/liter was similar, but weaker. The adjusted decrease in testosterone concentrations during the 11-yr follow-up was also greater in men with than without the metabolic syndrome. Smokers had a nonsignificantly lower risk of developing hypogonadism during follow-up, whereas a decrease in smoking increased the risk of hypogonadism. The metabolic syndrome predisposes to development of hypogonadism in middle-aged men. Prevention of abdominal obesity and the accompanying metabolic syndrome in middle age may decrease the risk of hypogonadism in men, especially in those who quit smoking.

Association between depressive symptoms and serum concentrations of homocysteine in men: a population study

BACKGROUND

Results of studies of the association between blood concentrations of homocysteine and depression in general populations and among psychiatric patients are inconsistent.

OBJECTIVE

The objective was to study the association between depression and serum concentrations of total homocysteine (tHcy).

DESIGN

A cross-sectional study of a sample of 924 men aged 46-64 y was conducted as a part of the Kuopio Ischaemic Heart Disease Risk Factor Study. Those who had a history of psychiatric disorder (6.0%) were excluded. Depressive symptoms were assessed with the 18-item Human Population Laboratory Depression Scale. Those who scored > or =5 at baseline or at the 4-y follow-up were considered to have a tendency toward depression.

RESULTS

The participants were ranked according to their blood tHcy concentration and divided into tertiles. Those in the upper tertile for serum tHcy had a more than twofold (odds ratio: 2.30; 95% CI: 1.35, 3.90; P=0.002) higher risk of being depressed than did those in the lowest tertile for serum tHcy. The results remained significant after adjustment for the month of study, history of ischemic heart disease, smoking habits, alcohol consumption, marital status, education, and socioeconomic status in adulthood (odds ratio: 2.23; 95% CI: 1.30, 3.83; P=0.004).

CONCLUSION

High serum concentrations of tHcy may be associated with depression in middle-aged men.

Dark chocolate consumption increases HDL cholesterol concentration and chocolate fatty acids may inhibit lipid peroxidation in healthy humans

Cocoa powder is rich in polyphenols and, thus, may contribute to the reduction of lipid peroxidation. Our aim was to study the effects of long-term ingestion of chocolate, with differing amounts of polyphenols, on serum lipids and lipid peroxidation ex vivo and in vivo. We conducted a 3 week clinical supplementation trial of 45 nonsmoking, healthy volunteers. Participants consumed 75 g daily of either white chocolate (white chocolate, WC group), dark chocolate (dark chocolate, DC group), or dark chocolate enriched with cocoa polyphenols (high-polyphenol chocolate, HPC group). In the DC and HPC groups, an increase in serum HDL cholesterol was observed (11.4% and 13.7%, respectively), whereas in the WC group there was a small decrease (-2.9%, p < 0.001). The concentration of serum LDL diene conjugates, a marker of lipid peroxidation in vivo, decreased 11.9% in all three study groups. No changes were seen in the total antioxidant capacity of plasma, in the oxidation susceptibility of serum lipids or VLDL + LDL, or in the concentration of plasma F2-isoprostanes or hydroxy fatty acids. Cocoa polyphenols may increase the concentration of HDL cholesterol, whereas chocolate fatty acids may modify the fatty acid composition of LDL and make it more resistant to oxidative damage.

Inflammation, abdominal obesity, and smoking as predictors of hypertension

Development of hypertension has been linked to chronic low-grade inflammation. However, it is not known whether this connection is mediated by features of the metabolic syndrome or smoking, or their changes, which themselves have been linked to inflammation. We studied the predictive value of highly sensitive C-reactive protein (hs-CRP), smoking, and abdominal obesity to the development of hypertension in an 11-year follow-up of a population-based study cohort comprising 379 middle-aged normotensive men. During the follow-up, 124 men (33%) developed hypertension. Men with hs-CRP > or =3.0 mg/L were 2.8x (95% confidence interval, 1.2 to 6.6) more likely to develop hypertension than with hs-CRP <1.0 mg/L even after adjustment for features of the metabolic syndrome, lifestyle factors, and their changes. Cigarette smoking was also associated with development of hypertension independently of inflammation and other confounders. Waist girth increased more in men who quit smoking than in other men. An increase in waist girth during follow-up strongly predicted incident hypertension. The decrease in smoking was not associated with a lower risk of hypertension in age-adjusted analyses. Hypertension is preceded by low-grade chronic inflammation in middle-aged white men independently of smoking or features of the metabolic syndrome. Furthermore, smoking may be a risk factor for hypertension. Although stopping smoking is beneficial with respect to health outcomes, the subsequent increase in weight and waist girth associated with smoking cessation may offset the decrease in the risk of hypertension that one may otherwise expect.

Adenovirus-mediated gene transfer of Lp-PLA2 reduces LDL degradation and foam cell formation in vitro

Oxidation of LDL generates biologically active platelet-activating factor (PAF)-like phospholipid derivatives, which have potent proinflammatory activity. These products are inactivated by lipoprotein-associated phospholipase A2 (Lp-PLA2), an enzyme capable of hydrolyzing PAF-like phospholipids. In this study, we generated an adenovirus (Ad) encoding human Lp-PLA2 and injected 10(8), 10(9), and 10(10) plaque-forming unit doses of Adlp-PLA2 and control AdlacZ intra-arterially into rabbits to achieve overexpression of Lp-PLA2 in liver and in vivo production of Lp-PLA2-enriched LDL. As a result, LDL particles with 3-fold increased Lp-PLA2 activity were produced with the highest virus dose. Increased Lp-PLA2 activity in LDL particles decreased the degradation rate in RAW 264 macrophages after standard in vitro oxidation to 60-80% compared with LDL isolated from LacZ-transduced control rabbits. The decrease was proportional to the virus dose and Lp-PLA2 activity. Lipid accumulation and foam cell formation in RAW 264 macrophages were also decreased when incubated with oxidized LDL containing the highest Lp-PLA2 activity. Inhibition of the Lp-PLA2 activity in the LDL particles led to an increase in lipid accumulation and foam cell formation. It is concluded that increased Lp-PLA2 activity in LDL attenuates foam cell formation and decreases LDL oxidation and subsequent degradation in macrophages.

Serum linoleic and total polyunsaturated fatty acids in relation to prostate and other cancers: a population-based cohort study

Dietary and serum fatty acid composition has been implicated in the pathogenesis of prostate and other cancers, but findings have been conflicting. Cohort studies reporting serum fatty acid composition are lacking. We assessed the association of fatty acid composition determined from dietary records and serum with incident cancer of the prostate and any site in a population-based cohort of 2,002 middle-aged Finnish men who were free of cancer at baseline and during the first 4 years of follow-up. During 12.6 years of follow-up, 46 men developed prostate cancer and 151 any cancer. Men with proportions of serum nonesterified [risk ratio (RR) 0.28; 95% confidence intervals (CI) 0.12-0.66] and esterified linoleic acid (RR 0.37; 95% CI = 0.16-0.86) and total polyunsaturated fatty acids (RR 0.30; 95% CI = 0.12-0.71) in the upper third were less than 1/3 as likely to develop prostate cancer during follow-up. Adjustment for possible confounders like socioeconomic status, physical activity, obesity and insulin concentrations did not attenuate the association. Similar but weaker associations with any cancer were found. Dietary linoleic acid intake also tended to be inversely associated with incident prostate cancer (age-adjusted RR for the upper vs. lower third 0.55; 95% CI = 0.26-1.14, p for the trend 0.097). Substitution of linoleic acid for saturated fat in middle-aged men consuming a high saturated-fat diet may decrease the risk of prostate and other cancers, although it is possible that some of the effect may be mediated by nutrients closely associated with vegetable fats.

Uric acid level as a risk factor for cardiovascular and all-cause mortality in middle-aged men: a prospective cohort study

BACKGROUND

Despite abundant epidemiologic evidence, the role of elevated serum uric acid level as a cardiovascular risk factor is controversial. We assessed the predictive value of serum uric acid levels for cardiovascular and overall mortality.

METHODS

A population-based prospective cohort study was performed of 1423 middle-aged Finnish men initially without cardiovascular disease, cancer, or diabetes. The main outcome measure was death from cardiovascular disease and any cause.

RESULTS

The mean follow-up was 11.9 years. There were 157 deaths during follow-up, of which 55 were cardiovascular. In age-adjusted analyses, serum uric acid levels in the upper third were associated with a greater than 2.5-fold higher risk of death from cardiovascular disease than levels in the lower third. Taking into account cardiovascular risk factors and variables commonly associated with gout increased the relative risk to 3.73. Further adjustment for factors related to the metabolic syndrome strengthened the risk to 4.77. Excluding the 53 men using diuretics did not alter the results. In age-adjusted analyses, men with serum uric acid levels in the upper third were 1.7-fold more likely to die of any cause than men with levels in the lower third. Adjustment for further risk factors strengthened the association somewhat.

CONCLUSIONS

Serum uric acid levels are a strong predictor of cardiovascular disease mortality in healthy middle-aged men, independent of variables commonly associated with gout or the metabolic syndrome. Serum uric acid measurement is an easily available and inexpensive risk marker, but whether its relationship to cardiovascular events is circumstantial or causal remains to be answered.

C-reactive protein and the development of the metabolic syndrome and diabetes in middle-aged men

AIMS/HYPOTHESIS

Low-grade inflammation has been implicated in the development of Type 2 diabetes and cardiovascular disease, but its role in the pathogenesis of the metabolic syndrome is unclear. We investigated the association between C-reactive protein (CRP) levels and the development of the metabolic syndrome and diabetes in men.

METHODS

Serum CRP concentrations and factors related to insulin resistance were determined in middle-aged Finnish men who participated in a population-based cohort study and were free of diabetes at baseline.

RESULTS

At the 11-year follow-up, 143 of 680 men had developed the metabolic syndrome as defined by the National Cholesterol Education Program (NCEP) and 103 of 598 men had developed the metabolic syndrome as defined by the World Health Organization (WHO). Our analyses excluded men with the metabolic syndrome by the respective definition at baseline. In all, 78 of 762 men developed diabetes over the same period. Men with CRP concentrations > or =3 mg/l had a several-fold higher age-adjusted risk of developing the metabolic syndrome (NCEP definition: odds ratio [OR]=3.2, 95% CI 1.9-5.5; WHO definition: OR=3.4, 95% CI 2.0-6.1) or diabetes (OR=4.1, 95% CI 2.1-8.0) than men whose CRP levels were <1.0 mg/l. Even after further adjustment for potentially confounding lifestyle factors and factors related to insulin resistance, the risk of diabetes (OR=2.3, 95% CI 1.0-5.1) was still increased in men with CRP concentrations > or =3 mg/l, but the association with the metabolic syndrome was no longer significant.

CONCLUSIONS/INTERPRETATION

Low-grade inflammation may increase the risk of the metabolic syndrome and diabetes in middle-aged men, but some of the risk is mediated through obesity and factors related to insulin resistance.