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Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide and challenges the capacity of health care systems globally. Atherosclerosis is the underlying pathophysiological entity in two-thirds of patients with CVD. When considering that atherosclerosis develops over decades, there is potentially great opportunity for prevention of associated events such as myocardial infarction and stroke. Subclinical atherosclerosis has been identified in its early stages in young individuals; however, there is no consensus on how to prevent progression to symptomatic disease. Given the growing burden of CVD, a paradigm shift is required-moving from late management of atherosclerotic CVD to earlier detection during the subclinical phase with the goal of potential cure or prevention of events. Studies must focus on how precision medicine using imaging and circulating biomarkers may identify atherosclerosis earlier and determine whether such a paradigm shift would lead to overall cost savings for global health., Competing Interests: Funding Support and Author Disclosures Funding was provided by Novo Nordisk Foundation, Hellerup, Denmark. Dr Johri has received honoraria from Novo Nordisk, BMS, and Janssen; and has received research support from Philips, GE Healthcare, and Lantheus. Dr Nordestgaard has received consultancies and/or given talks for AstraZeneca, Sanofi, Regeneron, Ionis, Amgen, Kowa, Denka, Amarin, Novartis, Novo Nordisk, Esperion, Abbott, Silence Therapeutics, Ultragenyx, USV, Mankind, Lilly, Arrowhead, and Marea. Dr MacRae has received grants from the National Institutes of Health and the American Heart Association (One Brave Idea, Apple Heart, and Movement Study) and Samsung; has consultancies with Bayer, Biosymetrics, Clarify Health, Dewpoint Therapeutics, Dinaqor, Dr Evidence, Foresite Labs, Insmed, Pfizer, and Platform Life Sciences; and is a co-founder of Atman Health and Tanaist. Dr Kofoed has received research grants from AP Møller and wife Chastine McKinney Møllers Foundation, The Novo Nordisk Foundation, Sygeforsikringen Danmark, Research Council of Rigshopitalet, The University of Copenhagen, Canon Medical Systems, and GE Healthcare. Dr Bøttcher has participated on the advisory board for AstraZeneca, Bayer, Boehringer Ingelheim, Novartis, Novo Nordisk, and Sanofi. Dr Shapiro has served on the scientific advisory boards for Agepha, Amgen, Ionis, and Novartis; and has been a consultant for Amgen, Ionis, Novartis, Regeneron, and Shanghai Pharma Biotherapeutics. Dr Budoff has received grant support from General Electric. Dr Douglas has received research support from HeartFlow and Caption Health; and has received honoraria from UpToDate and Foresite Labs. Dr Nicholls has received research support from AstraZeneca, Amgen, Anthera, CSL Behring, Cerenis, Eli Lilly, Esperion, Resverlogix, New Amsterdam Pharma, Novartis, InfraReDx, and Sanofi-Regeneron; and has consultancies with Amgen, Akcea, Arrowhead, AstraZeneca, Boehringer Ingelheim, CSL Behring, Eli Lilly, Esperion, Kowa, Merck, Takeda, Pfizer, Sanofi-Regeneron, Vaxxinity, CSL Sequiris, Cyclarity, and Novo Nordisk. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 American College of Cardiology Foundation. All rights reserved.)

Background: Lead exposure is associated with cardiovascular disease. Atherosclerosis has been hypothesized to be one of the underlying mechanisms behind this association., Aim: To investigate whether lead exposure is associated with an increased risk of atherosclerosis in the carotid arteries in a large Swedish population-based cohort., Methods: We performed a cross-sectional study using data from the population-based Swedish CardioPulmonary bioImage Study (SCAPIS), including 5622 middle-aged men and women, enrolled 2013-2018. Blood lead (B-Pb), measured by inductively coupled plasma mass spectrometry, was used as exposure biomarker. The presence of atherosclerotic plaque in the carotid arteries (yes/no), total plaque area (mm 2 ) and the presence of large plaques (>25 mm 2 ) were determined by ultrasonography. Associations between B-Pb and the different outcomes were analysed using Poisson and linear regression models, adjusted for potential confounders., Results: Atherosclerotic plaque was present in 57% of the individuals, for whom the median total plaque area was 16 mm 2 (range: 0.2-222). The median B-Pb concentration was 14 μg/L (range: 0.75-203). After adjusting for potential confounders, individuals in the fourth quartile of B-Pb (Q4) had a prevalence ratio (PR) for plaque of 1.08 (95% CI: 1.01, 1.16) when compared with the first quartile (Q1). A 10 μg/L increase in B-Pb concentrations was associated with an increase of 0.92 mm 2 (95% CI: 0.14, 1.71) in total plaque area. The PR for large plaque was 1.09 (95% CI: 0.84, 1.42 for Q4 vs Q1)., Conclusions: This study shows an association between B-Pb and atherosclerosis in the carotid arteries providing some support for the hypothesis that atherosclerosis is one of the mechanisms underlying the association between lead exposure and cardiovascular disease., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Reduced lung function is associated with cardiovascular mortality, but the relationships with atherosclerosis are unclear. The population-based Swedish CArdioPulmonary BioImage study measured lung function, emphysema, coronary CT angiography, coronary calcium, carotid plaques and ankle-brachial index in 29,593 men and women aged 50-64 years. The results were confirmed using 2-sample Mendelian randomization. Lower lung function and emphysema were associated with more atherosclerosis, but these relationships were attenuated after adjustment for cardiovascular risk factors. Lung function was not associated with coronary atherosclerosis in 14,524 never-smokers. No potentially causal effect of lung function on atherosclerosis, or vice versa, was found in the 2-sample Mendelian randomization analysis. Here we show that reduced lung function and atherosclerosis are correlated in the population, but probably not causally related. Assessing lung function in addition to conventional cardiovascular risk factors to gauge risk of subclinical atherosclerosis is probably not meaningful, but low lung function found by chance should alert for atherosclerosis., (© 2023. The Author(s).)

Coronary artery calcification (CAC) is an established imaging biomarker of subclinical atherosclerosis, but its relationship to diurnal preference is not well studied. We investigated the association between chronotype and CAC in the Swedish CArdioPulmonary bioImage Study (SCAPIS) pilot cohort. Participants aged 50-64 years were randomly recruited and underwent extensive examination including imaging and accelerometry-assessed physical activity. 771 participants (47.3 % male, 57.6 ± 4.4 years) were included in this cross-sectional analysis. CAC was assessed by non-contrast computed tomography, and a CAC score > 10 was considered significant calcification. Self-assessed chronotype was classified as extreme morning, moderate morning, intermediate, moderate evening, or extreme evening. 10-year risk of first-onset cardiovascular disease was estimated by the Systemic Coronary Risk Evaluation 2 (SCORE2). Significant CAC was present in 29 % of the cohort. CAC prevalence increased from extreme morning to extreme evening type (22 %, 28 %, 29 %, 27 %, 41 % respectively, p = 0.018). In a multivariate logistic regression model controlling for confounders, extreme evening chronotype was independently associated with increased CAC prevalence compared to extreme morning type (OR 1.90, [95%CI 1.04-3.46], p = 0.037). When stratified by SCORE2 risk category (low: <5 %; moderate: 5 to <10 %; high: ≥10 %), significant CAC was most prevalent among extreme evening chronotypes in the low and moderate-risk groups, while chronotype seemed less important in the high-risk group (p = 0.011, p = 0.023, p = 0.86, respectively). Our findings suggest circadian factors may play an important role in atherosclerosis and should be considered in early cardiovascular prevention., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Patients with type 2 diabetes have an increased risk of death and cardiovascular events and people with diabetes or prediabetes have been found to have increased atherosclerotic burden in the coronary and carotid arteries. This study will estimate the cross-sectional prevalence of atherosclerosis in the coronary and carotid arteries in individuals with prediabetes and diabetes, compared with normoglycaemic individuals in a large population-based cohort., Methods: The 30,154 study participants, 50-64 years, were categorized according to their fasting glycaemic status or self-reported data as normoglycaemic, prediabetes, and previously undetected or known diabetes. Prevalence of affected coronary artery segments, severity of stenosis and coronary artery calcium score (CACS) were determined by coronary computed tomography angiography. Total atherosclerotic burden was assessed in the 11 clinically most relevant segments using the Segment Involvement Score and as the presence of any coronary atherosclerosis. The presence of atherosclerotic plaque in the carotid arteries was determined by ultrasound examination., Results: Study participants with prediabetes (n = 4804, 16.0%) or diabetes (n = 2282, 7.6%) had greater coronary artery plaque burden, more coronary stenosis and higher CACS than normoglycaemic participants (all, p < 0.01). Among male participants with diabetes 35.3% had CACS ≥ 100 compared to 16.1% among normoglycaemic participants. For women, the corresponding figures were 8.9% vs 6.1%. The prevalence of atherosclerosis in the coronary arteries was higher in participants with previously undetected diabetes than prediabetes, but lower than in patients with known diabetes. The prevalence of any plaque in the carotid arteries was higher in participants with prediabetes or diabetes than in normoglycaemic participants., Conclusions: In this large population-based cohort of currently asymptomatic people, the atherosclerotic burden in the coronary and carotid arteries increased with increasing degree of dysglycaemia. The finding that the atherosclerotic burden in the coronary arteries in the undetected diabetes category was midway between the prediabetes category and patients with known diabetes may have implications for screening strategies and tailored prevention interventions for people with dysglycaemia in the future., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Non-alcoholic fatty liver disease (NAFLD) is associated with increased secretion of apoB-containing lipoproteins and increased risk of coronary heart disease (CHD). ApoB-containing lipoproteins include low-density lipoproteins (LDLs) and triglyceride-rich lipoproteins (TRLs); and since both LDLs and TRLs are causally related to CHD, they may mediate a portion of the increased risk of atherosclerosis seen in people with NAFLD. In a cohort of 4161 middle aged men and women, we performed mediation analysis in order to quantify the mediating effect of apoB-containing lipoproteins in the relationship between liver fat and atherosclerosis-as measured by coronary artery calcium score (CACS). We found plasma apoB to mediate 17.6% (95% CI 11-24) of the association between liver fat and CACS. Plasma triglycerides and TRL-cholesterol (both proximate measures of TRL particles) mediated 22.3% (95% CI 11-34) and 21.6% (95% CI 10-33) of the association respectively; whereas LDL-cholesterol mediated 5.4% (95% CI 2.0-9.4). In multivariable models, the mediating effect of TRL-cholesterol and plasma triglycerides showed, again, a higher degree of mediation than LDL-cholesterol, corroborating the results seen in the univariable models. In summary, we find around 20% of the association between liver fat and CACS to be mediated by apoB-containing lipoproteins. In addition, we find that TRLs mediate the majority of this effect whereas LDLs mediate a smaller effect. These results explain part of the observed CAD-risk burden for people with NAFLD and further suggest that TRL-lowering may be particularly beneficial to mitigate NAFLD-associated coronary artery disease risk., (© 2023. Springer Nature Limited.)

Background: Gut microbiota have been implicated in atherosclerotic disease, but their relation with subclinical coronary atherosclerosis is unclear. This study aimed to identify associations between the gut microbiome and computed tomography-based measures of coronary atherosclerosis and to explore relevant clinical correlates., Methods: We conducted a cross-sectional study of 8973 participants (50 to 65 years of age) without overt atherosclerotic disease from the population-based SCAPIS (Swedish Cardiopulmonary Bioimage Study). Coronary atherosclerosis was measured using coronary artery calcium score and coronary computed tomography angiography. Gut microbiota species abundance and functional potential were assessed with shotgun metagenomics sequencing of fecal samples, and associations with coronary atherosclerosis were evaluated with multivariable regression models adjusted for cardiovascular risk factors. Associated species were evaluated for association with inflammatory markers, metabolites, and corresponding species in saliva., Results: The mean age of the study sample was 57.4 years, and 53.7% were female. Coronary artery calcification was detected in 40.3%, and 5.4% had at least 1 stenosis with >50% occlusion. Sixty-four species were associated with coronary artery calcium score independent of cardiovascular risk factors, with the strongest associations observed for Streptococcus anginosus and Streptococcus oralis subsp oralis ( P <1×10 -5 ). Associations were largely similar across coronary computed tomography angiography-based measurements. Out of the 64 species, 19 species, including streptococci and other species commonly found in the oral cavity, were associated with high-sensitivity C-reactive protein plasma concentrations, and 16 with neutrophil counts. Gut microbial species that are commonly found in the oral cavity were negatively associated with plasma indole propionate and positively associated with plasma secondary bile acids and imidazole propionate. Five species, including 3 streptococci, correlated with the same species in saliva and were associated with worse dental health in the Malmö Offspring Dental Study. Microbial functional potential of dissimilatory nitrate reduction, anaerobic fatty acid β-oxidation, and amino acid degradation were associated with coronary artery calcium score., Conclusions: This study provides evidence of an association of a gut microbiota composition characterized by increased abundance of Streptococcus spp and other species commonly found in the oral cavity with coronary atherosclerosis and systemic inflammation markers. Further longitudinal and experimental studies are warranted to explore the potential implications of a bacterial component in atherogenesis., Competing Interests: Disclosures S. Pita, N. Nielsen, and Drs Eklund, Holm, and Nielsen are employees of Clinical Microbiomics A/S, where samples were processed and DNA extraction and estimations of relative abundance of the metagenomics species were done. Dr Ärnlöv has received lecture fees from Novartis and AstraZeneca and has served on advisory boards for AstraZeneca and Boehringer Ingelheim, all unrelated to the article. Dr Nilsson has received lecture fees from Novartis, Novo Nordisk, Amgen, and Boehringer Ingelheim. The other authors declare no competing interests.

Background and Aims: Previous studies reported divergent results on whether metabolically healthy obesity is associated with increased coronary artery calcium and carotid plaques. We investigated this in a cross-sectional fashion in a large, well-defined, middle-aged population using coronary CT angiography (CCTA) and carotid ultrasound., Methods: In the SCAPIS study (50-65 years, 51% female), CCTA and carotid artery ultrasound were performed in 23,674 individuals without clinical atherosclerotic disease. These subjects were divided into six groups according to BMI (normal weight, overweight, obese) and the presence of metabolic syndrome (MetS) according to the NCEP consensus criteria., Results: The severity of coronary artery stenosis was increased in individuals with obesity without MetS compared to normal-weight individuals without MetS (OR 1.47, 95%CI 1.34-1.62; p < 0.0001), even after adjusting for non-HDL-cholesterol and several lifestyle factors. Such difference was not observed for the presence of carotid artery plaques (OR 0.94, 95%CI 0.87-1.02; p = 0.11). Obese or overweight individuals without any MetS criteria (except the waist criterion) showed significantly more pronounced stenosis in the coronary arteries as compared to the normal-weight individuals, while one criterion was needed to show increased plaque prevalence in the carotid arteries. High blood pressure was the most important single criterion for increased atherosclerosis in this respect., Conclusions: Individuals with obesity without MetS showed increased severity of coronary artery stenosis, but no increased occurrence of carotid artery plaques compared to normal-weight individuals without MetS, further emphasizing that obesity is not a benign condition even in the absence of MetS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Long-term exposure to air pollution is associated with cardiovascular events. A main suggested mechanism is that air pollution accelerates the progression of atherosclerosis, yet current evidence is inconsistent regarding the association between air pollution and coronary artery and carotid artery atherosclerosis, which are well-established causes of myocardial infarction and stroke. We studied associations between low levels of long-term air pollution, coronary artery calcium (CAC) score, and the prevalence and area of carotid artery plaques, in a middle-aged population-based cohort. The Swedish CArdioPulmonary bioImage Study (SCAPIS) Gothenburg cohort was recruited during 2013-2017 and thoroughly examined for cardiovascular risk factors, including computed tomography of the heart and ultrasonography of the carotid arteries. In 5070 participants (age 50-64 years), yearly residential exposures to air pollution (PM 2.5 , PM 10 , PM coarse , NO x , and exhaust-specific PM 2.5 1990-2015) were estimated using high-resolution dispersion models. We used Poisson regression to examine associations between long-term (26 years' mean) exposure to air pollutants and CAC score, and prevalence of carotid artery plaques, adjusted for potential confounders. Among participants with carotid artery plaques, we also examined the association with plaque area using linear regression. Mean exposure to PM 2.5 was low by international standards (8.5 μg/m 3 ). There were no consistent associations between long-term total PM 2.5 exposure and CAC score or presence of carotid artery plaques, but an association between total PM 2.5 and larger plaque area in participants with carotid plaques. Associations with traffic-related air pollutants were consistently positive for both a high CAC score and bilateral carotid artery plaques. These associations were independent of road traffic noise. We found stronger associations among men and participants with cardiovascular risk factors. The results lend some support to atherosclerosis as a main modifiable pathway between low levels of traffic-related ambient air pollution and cardiovascular disease, especially in vulnerable individuals., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population., Methods: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data., Results: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population., Conclusions: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.

Background: The general population is ubiquitously exposed to the toxic metal cadmium through the diet and smoking. Cadmium exposure is associated with increased morbidity and mortality in myocardial infarction and stroke. Atherosclerosis is the main underlying mechanism of myocardial infarction. However, associations between cadmium and coronary artery atherosclerosis have not been examined., Objectives: Our study sought to examine the hypothesis that blood cadmium (B-Cd) is positively associated with coronary artery calcification, as a measure of coronary artery atherosclerosis in the population-based Swedish SCAPIS study., Methods: Our analysis included 5,627 individuals (51% women), age 50-64 y, enrolled from 2013 to 2018. The coronary artery calcium score (CACS) was obtained from computed tomography. Blood cadmium was determined by inductively coupled plasma mass spectrometry (ICP-MS). Associations between B-Cd and coronary artery calcium score (CACS Agatston score) were evaluated using prevalence ratios (PRs) in models adjusted for sex, age, smoking, hypertension, diabetes, low-density cholesterol/high-density cholesterol ratio, and family history., Results: The median B-Cd concentration was 0.24 μ g / L . The prevalence of positive coronary artery calcium ( CACS > 0 ) was 41% and the prevalence of CACS ≥ 100 was 13%. Relative to the lowest quartile (Q) of B-Cd ( < 0.16 μ g / L ), the highest quartile (median 0.63 μ g / L ) was associated with a small but significant increase in CACS > 0 (PR 1.1; 95% CI: 1.0, 1.3), and a greater relative increase in CACS ≥ 100 (PR 1.6; 95% CI: 1.3, 2.0). When restricted to 2,446 never-smokers, corresponding PRs were 1.1 (95% CI 0.9, 1.3) for CACS > 0 (63 cases in Q4) and 1.7 (95% CI 1.1, 2.7) for CACS ≥ 100 (17 cases in Q4)., Discussion: Blood cadmium in the highest quartile was associated with CACS in a general population sample with low to moderate cadmium exposure. This supports the hypothesis that atherosclerosis is an important mechanism underlying the associations between cadmium and incident cardiovascular disease. The findings suggest that public health measures to reduce cadmium exposure are warranted. https://doi.org/10.1289/EHP8523.

Background: It is not clear if the European Systematic Coronary Risk Evaluation algorithm is useful for identifying prevalent subclinical atherosclerosis in a population of apparently healthy individuals. Our aim was to explore the association between the risk estimates from Systematic Coronary Risk Evaluation and prevalent subclinical atherosclerosis., Design: The design of this study was as a cross-sectional analysis from a population-based study cohort., Methods: From the general population, the Swedish Cardiopulmonary Bioimage Study randomly invited individuals aged 50-64 years and enrolled 13,411 participants mean age 57 (standard deviation 4.3) years; 46% males between November 2013-December 2016. Associations between Systematic Coronary Risk Evaluation risk estimates and coronary artery calcification and plaques in the carotid arteries by using imaging data from a computed tomography of the heart and ultrasonography of the carotid arteries were examined., Results: Coronary calcification was present in 39.5% and carotid plaque in 56.0%. In men, coronary artery calcium score >0 ranged from 40.7-65.9% and presence of carotid plaques from 54.5% to 72.8% in the age group 50-54 and 60-65 years, respectively. In women, the corresponding difference was from 17.1-38.9% and from 41.0-58.4%. A doubling of Systematic Coronary Risk Evaluation was associated with an increased probability to have coronary artery calcium score >0 (odds ratio: 2.18 (95% confidence interval 2.07-2.30)) and to have >1 carotid plaques (1.67 (1.61-1.74))., Conclusion: Systematic Coronary Risk Evaluation estimated risk is associated with prevalent subclinical atherosclerosis in two major vascular beds in a general population sample without established cardiovascular disease or diabetes mellitus. Thus, the Systematic Coronary Risk Evaluation risk chart may be of use for estimating the risk of subclinical atherosclerosis., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Cardiology.)

The Rho GTPase RAC1 is an important regulator of cytoskeletal dynamics, but the role of macrophage-specific RAC1 has not been explored during atherogenesis. We analyzed RAC1 expression in human carotid atherosclerotic plaques using immunofluorescence and found higher macrophage RAC1 expression in advanced plaques compared with intermediate human atherosclerotic plaques. We then produced mice with Rac1-deficient macrophages by breeding conditional floxed Rac1 mice (Rac1fl/fl) with mice expressing Cre from the macrophage-specific lysosome M promoter (LC). Atherosclerosis was studied in vivo by infecting Rac1fl/fl and Rac1fl/fl/LC mice with AdPCSK9 (adenoviral vector overexpressing proprotein convertase subtilisin/kexin type 9). Rac1fl/fl/LC macrophages secreted lower levels of IL-6 and TNF-α and exhibited reduced foam cell formation and lipid uptake. The deficiency of Rac1 in macrophages reduced the size of aortic atherosclerotic plaques in AdPCSK9-infected Rac1fl/fl/LC mice. Compare with controls, intima/media ratios, the size of necrotic cores, and numbers of CD68-positive macrophages in atherosclerotic plaques were reduced in Rac1-deficient mice. Moreover, we found that RAC1 interacts with actin-binding filamin A. Macrophages expressed increased RAC1 levels in advanced human atherosclerosis. Genetic inactivation of RAC1 impaired macrophage function and reduced atherosclerosis in mice, suggesting that drugs targeting RAC1 may be useful in the treatment of atherosclerosis., Competing Interests: The authors have declared that no competing interests exist.

Atherosclerosis - the pathophysiological mechanism shared by most cardiovascular diseases - can be directly or indirectly assessed by a variety of clinical tests including measurement of carotid intima-media thickness, carotid plaque, -ankle-brachial index, pulse wave velocity, and coronary -artery calcium. The Prospective Studies of Atherosclerosis -(Proof-ATHERO) consortium (https://clinicalepi.i-med.ac.at/research/proof-athero/) collates de-identified individual-participant data of studies with information on atherosclerosis measures, risk factors for cardiovascular disease, and incidence of cardiovascular diseases. It currently comprises 74 studies that involve 106,846 participants from 25 countries and over 40 cities. In summary, 21 studies recruited participants from the general population (n = 67,784), 16 from high-risk populations (n = 22,677), and 37 as part of clinical trials (n = 16,385). Baseline years of contributing studies range from April 1980 to July 2014; the latest follow-up was until June 2019. Mean age at baseline was 59 years (standard deviation: 10) and 50% were female. Over a total of 830,619 person-years of follow-up, 17,270 incident cardiovascular events (including coronary heart disease and stroke) and 13,270 deaths were recorded, corresponding to cumulative incidences of 2.1% and 1.6% per annum, respectively. The consortium is coordinated by the Clinical Epidemiology Team at the Medical University of Innsbruck, Austria. Contributing studies undergo a detailed data cleaning and harmonisation procedure before being incorporated in the Proof-ATHERO central database. Statistical analyses are being conducted according to pre-defined analysis plans and use established methods for individual-participant data meta-analysis. Capitalising on its large sample size, the multi-institutional collaborative Proof-ATHERO consortium aims to better characterise, understand, and predict the development of atherosclerosis and its clinical consequences., (© 2020 S. Karger AG, Basel.)

Background: The actin-binding protein FLNA (filamin A) regulates signal transduction important for cell locomotion, but the role of macrophage-specific FLNA during atherogenesis has not been explored., Methods: We analyzed FLNA expression in human carotid atherosclerotic plaques by immunofluorescence. We also produced mice with Flna-deficient macrophages by breeding conditional Flna-knockout mice ( Flna o/fl ) with mice expressing Cre from the macrophage-specific lysosome M promoter ( LC). Atherosclerosis in vivo was studied by transplanting bone marrow from male Flna o/fl / LC mice to atherogenic low-density lipoprotein receptor-deficient ( Ldlr -/- ) mice; and by infecting Flna o/fl and Flna o/fl / LC mice with AdPCSK9 (adenoviral vector overexpressing proprotein convertase subtilisin/kexin type 9). Furthermore, C57BL/6 mice were infected with AdPCSK9 and then treated with the calpain inhibitor calpeptin to inhibit FLNA cleavage., Results: We found that macrophage FLNA expression was higher in advanced than in intermediate human atherosclerotic plaques. Flna o/fl / LC macrophages proliferated and migrated less than controls; expressed lower levels of phosphorylated AKT and ERK1/2; exhibited reduced foam cell formation and lipid uptake; and excreted more lipids. The deficiency of Flna in macrophages markedly reduced the size of aortic atherosclerotic plaques in both Ldlr -/-BMT: Flnao/fl/LC and AdPCSK9-infected Flna o/fl / LC mice. Intima/media ratios and numbers of CD68-positive macrophages in atherosclerotic plaques were lower in Flna-deficient mice than in control mice. Moreover, we found that STAT3 interacts with a calpain-cleaved carboxyl-terminal fragment of FLNA. Inhibiting calpain-mediated FLNA cleavage with calpeptin in macrophages reduced nuclear levels of phosphorylated STAT3, interleukin 6 secretion, foam cell formation, and lipid uptake. Finally, calpeptin treatment reduced the size of atherosclerotic plaques in C57BL/6 mice infected with AdPCSK9., Conclusions: Genetic inactivation of Flna and chemical inhibition of calpain-dependent cleavage of FLNA impaired macrophage signaling and function, and reduced atherosclerosis in mice, suggesting that drugs targeting FLNA may be useful in the treatment of atherosclerosis.

Background and Aims: Several studies have confirmed the presence of bacterial DNA in atherosclerotic plaques, but its contribution to plaque stability and vulnerability is unclear. In this study, we investigated whether the bacterial plaque-profile differed between patients that were asymptomatic or symptomatic and whether there were local differences in the microbial composition within the plaque., Methods: Plaques were removed by endarterectomy from asymptomatic and symptomatic patients and divided into three different regions known to show different histological vulnerability: A, upstream of the maximum stenosis; B, site for maximum stenosis; C, downstream of the maximum stenosis. Bacterial DNA composition in the plaques was determined by performing 454 pyrosequencing of the 16S rRNA genes, and total bacterial load was determined by qPCR., Results: We confirmed the presence of bacterial DNA in the atherosclerotic plaque by qPCR analysis of the 16S rRNA gene but observed no difference (n.s.) in the amount between either asymptomatic and symptomatic patients or different plaque regions A, B and C. Unweighted UniFrac distance metric analysis revealed no distinct clustering of samples by patient group or plaque region. Operational taxonomic units (OTUs) from 5 different phyla were identified, with the majority of the OTUs belonging to Proteobacteria (48.3%) and Actinobacteria (40.2%). There was no difference between asymptomatic and symptomatic patients, or plaque regions, when analyzing the origin of DNA at phylum, family or OTU level (n.s.)., Conclusions: There were no major differences in bacterial DNA amount or microbial composition between plaques from asymptomatic and symptomatic patients or between different plaque regions, suggesting that other factors are more important in determining plaque vulnerability., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background: Autonomic dysfunction is a risk factor for cardiovascular disease (CVD), however, the exact mechanism linking autonomic dysfunction to cardiovascular disease is not known. In this study we hypothesized that autonomic dysfunction increases inflammation, which subsequently accelerates atherosclerosis. The aim of the current study was to investigate the association between autonomic tone, inflammation and atherosclerosis., Methods: 124 men under investigation for carotid atherosclerosis were examined for autonomic function (heart rate variability; HRV and baroreflex sensitivity; BRS), inflammatory markers (white blood cell count; WBCC and C-reactive protein; CRP) and degree of carotid atherosclerosis. The direct or indirect associations between autonomic function, inflammatory parameters and carotid plaque area were investigated with multiple linear regressions., Results: Male subjects with prevalent CVD showed larger carotid plaque area, higher WBCC, and reduced BRS compared to subjects with no history of CVD. Further, BRS was inversely associated with carotid plaque area (r = -0.21, p = 0.018) as well as inflammatory parameters WBCC and CRP (r = -0.29, p = 0.001, and r = -0.23, p = 0.009, respectively), whereas HRV only was inversely associated with WBCC (r = -0.22, p = 0.014). To investigate if inflammation could provide a link between autonomic function and carotid atherosclerosis we adjusted the associations accordingly. After adjusting for WBCC and CRP the inverse association between BRS and carotid plaque area was attenuated and did not remain significant, while both WBCC and CRP remained significantly associated with carotid plaque area, indicating that low-grade inflammation can possibly link BRS to atherosclerosis. Also, after adjusting for age, antihypertensive treatment and cardiovascular risk factors, BRS was independently inversely associated with both WBCC and CRP, and HRV independently inversely associated with WBCC. WBCC was the only inflammatory marker independently associated with carotid plaque area after adjustment., Conclusions: We demonstrate that autonomic dysfunction is associated with atherosclerosis and that inflammation could play an important role in mediating this relationship.

Background: The clinical use of carotid intima media thickness (cIMT) requires normal values, which may be subject to variation of geographical factors, ethnicity or measurement details. The influence of these factors has rarely been studied. The aim of this study was to determine whether normative cIMT values and their association with event risk are generalizable across populations., Design: Meta-analysis of individual participant data., Method: From 22 general population cohorts from Europe, North America and Asia we selected subjects free of cardiovascular disease. Percentiles of cIMT and cIMT progression were assessed separately for every cohort. Cox proportional hazards models for vascular events were used to estimate hazard ratios for cIMT in each cohort. The estimates were pooled across Europe, North America and Asia, with random effects meta-analysis. The influence of geography, ethnicity and ultrasound protocols on cIMT values and on the hazard ratios was examined by meta-regression., Results: Geographical factors, ethnicity and the ultrasound protocol had influence neither on the percentiles of cIMT and its progression, nor on the hazard ratios of cIMT for vascular events. Heterogeneity for percentiles of cIMT and cIMT progression was too large to create meaningful normative values., Conclusions: The distribution of cIMT values is too heterogeneous to define universal or regional population reference values. CIMT values vary widely between different studies regardless of ethnicity, geographic location and ultrasound protocol. Prediction of vascular events with cIMT values was more consistent across all cohorts, ethnicities and regions., (© The European Society of Cardiology 2016.)

Background: Large-scale epidemiological evidence on the role of inflammation in early atherosclerosis, assessed by carotid ultrasound, is lacking. We aimed to quantify cross-sectional and longitudinal associations of inflammatory markers with common-carotid-artery intima-media thickness (CCA-IMT) in the general population., Methods: Information on high-sensitivity C-reactive protein, fibrinogen, leucocyte count and CCA-IMT was available in 20 prospective cohort studies of the PROG-IMT collaboration involving 49,097 participants free of pre-existing cardiovascular disease. Estimates of associations were calculated within each study and then combined using random-effects meta-analyses., Results: Mean baseline CCA-IMT amounted to 0.74 mm (SD = 0.18) and mean CCA-IMT progression over a mean of 3.9 years to 0.011 mm/year (SD = 0.039). Cross-sectional analyses showed positive linear associations between inflammatory markers and baseline CCA-IMT. After adjustment for traditional cardiovascular risk factors, mean differences in baseline CCA-IMT per one-SD higher inflammatory marker were: 0.0082 mm for high-sensitivity C-reactive protein (p < 0.001); 0.0072 mm for fibrinogen (p < 0.001); and 0.0025 mm for leucocyte count (p = 0.033). 'Inflammatory load', defined as the number of elevated inflammatory markers (i.e. in upper two quintiles), showed a positive linear association with baseline CCA-IMT (p < 0.001). Longitudinal associations of baseline inflammatory markers and changes therein with CCA-IMT progression were null or at most weak. Participants with the highest 'inflammatory load' had a greater CCA-IMT progression (p = 0.015)., Conclusion: Inflammation was independently associated with CCA-IMT cross-sectionally. The lack of clear associations with CCA-IMT progression may be explained by imprecision in its assessment within a limited time period. Our findings for 'inflammatory load' suggest important combined effects of the three inflammatory markers on early atherosclerosis., (© The European Society of Cardiology 2014.)

Rationale: Cell proliferation and cell cycle control mechanisms are thought to play central roles in the pathogenesis of atherosclerosis. The transcription factor Zinc finger protein 148 (Zfp148) was shown recently to maintain cell proliferation under oxidative conditions by suppressing p53, a checkpoint protein that arrests proliferation in response to various stressors. It is established that inactivation of p53 accelerates atherosclerosis, but whether increased p53 activation confers protection against the disease remains to be determined., Objective: We aimed to test the hypothesis that Zfp148 deficiency reduces atherosclerosis by unleashing p53 activity., Methods and Results: Mice harboring a gene-trap mutation in the Zfp148 locus (Zfp148(gt/+)) were bred onto the apolipoprotein E (Apoe)(-/-) genetic background and fed a high-fat or chow diet. Loss of 1 copy of Zfp148 markedly reduced atherosclerosis without affecting lipid metabolism. Bone marrow transplantation experiments revealed that the effector cell is of hematopoietic origin. Peritoneal macrophages and atherosclerotic lesions from Zfp148(gt/+)Apoe(-/-) mice showed increased levels of phosphorylated p53 compared with controls, and atherosclerotic lesions contained fewer proliferating macrophages. Zfp148(gt/+)Apoe(-/-) mice were further crossed with p53-null mice (Trp53(-/-) [the gene encoding p53]). There was no difference in atherosclerosis between Zfp148(gt/+)Apoe(-/-) mice and controls on a Trp53(+/-) genetic background, and there was no difference in levels of phosphorylated p53 or cell proliferation., Conclusions: Zfp148 deficiency increases p53 activity and protects against atherosclerosis by causing proliferation arrest of lesional macrophages, suggesting that drugs targeting macrophage proliferation may be useful in the treatment of atherosclerosis., (© 2014 American Heart Association, Inc.)

A few studies in animals and humans suggest that metoprolol (β1-selective adrenoceptor antagonist) may have a direct antiatherosclerotic effect. However, the mechanism behind this protective effect has not been established. The aim of the present study was to evaluate the effect of metoprolol on development of atherosclerosis in ApoE(-/-) mice and investigate its effect on the release of proinflammatory cytokines. Male ApoE(-/-) mice were treated with metoprolol (2.5 mg/kg/h) or saline for 11 weeks via osmotic minipumps. Atherosclerosis was assessed in thoracic aorta and aortic root. Total cholesterol levels and Th1/Th2 cytokines were analyzed in serum and macrophage content in lesions by immunohistochemistry. Metoprolol significantly reduced atherosclerotic plaque area in thoracic aorta (P < 0.05 versus Control). Further, metoprolol reduced serum TNFα and the chemokine CXCL1 (P < 0.01 versus Control for both) as well as decreasing the macrophage content in the plaques (P < 0.01 versus Control). Total cholesterol levels were not affected. In this study we found that a moderate dose of metoprolol significantly reduced atherosclerotic plaque area in thoracic aorta of ApoE(-/-) mice. Metoprolol also decreased serum levels of proinflammatory cytokines TNFα and CXCL1 and macrophage content in the plaques, showing that metoprolol has an anti-inflammatory effect.

Introduction: We have previously shown that different forms of stress have distinctive effects on atherogenesis in mice. We showed that social stress increase atherosclerosis in ApoE(-/-) mice, while more physical forms of stress do not. Here we evaluated the effect of social disruption (SDR) stress on atherogenesis and evaluated cytokine release after SDR-stress and five more physical stressors., Methods: Male ApoE(-/-) mice were exposed to SDR-stress during 12 weeks, and atherosclerotic plaque area was assessed in aorta, aortic root and innominate artery. Further, male C57BL/6 mice were exposed to SDR-stress or five physical stressors, and cytokine and corticosterone levels were analyzed in plasma/serum samples immediately after stress., Results: We found a correlation between the level of SDR-stress and atherosclerotic plaque area in aorta and a numerical increased plaque area in aortic root. SDR stress did not affect histological features of plaque composition. However, SDR-stress increased levels of corticosterone, IL-6 and CXCL1. Plasma corticosterone increased for all five physical stressors, but IL-6 and CXCL1 only increased in the group exposed to restraint combined with rat odor., Conclusions: These findings suggest that SDR-stress is indeed atherogenic, in contrast to our previous results using the physical stressors. A possible explanation to this difference is that SDR-stress, but not physical stressors, leads to release of the pro-inflammatory cytokines IL-6 and CXCL1., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Psychosocial stress is suggested to play a significant role in development of cardiovascular disease. To evaluate the effects of repeated exposure to stress on atherosclerosis in atherosclerosis-prone ApoE(-/-) mice we used five different stressors. We further sought to determine whether stress combined with high salt diet induces dysfunctional neurohormonal regulation and impaired salt excretion, thus amplifying the atherogenic potential of salt. The five stressors were evaluated in male C57BL/6 mice and ApoE(-/-) mice (studies I and II) and then used in female ApoE(-/-) mice to study their effect on atherosclerosis (study III). The mice in study III received standard or high salt diet (8%) alone or in combination with stress for 12 weeks. Urine and plasma were collected for corticosterone and lipid analysis, respectively. Acute blood pressure (BP) and heart rate (HR) responses to stress were measured using telemetry. Plaque burden was assessed in the thoracic aorta and aortic root. Plaque morphology was investigated regarding macrophages and collagen content. Urinary corticosterone chronically increased in stressed mice (P<0.05 control vs. stress, P<0.05 control salt vs. stress salt). BP and HR increased acutely during all stressors (P<0.05). Body weight gain decreased significantly in the stress group (P<0.05 vs. control). However, stress did not alter plasma lipid levels, plaque area or plaque morphology. Increased BP and HR suggest an acute stress-related response in ApoE(-/-) mice. Furthermore, stress chronically decreased body weight gain and increased urinary corticosterone levels. Notably, despite an apparent stress effect, stress affected neither atherogenesis nor plaque morphology.

Objectives: High-salt diet likely elevates blood pressure (BP), thus increasing the risk of cardiovascular events. We hypothesized that a high-salt diet plays a critical role in subjects whose renin-angiotensin systems cannot adjust to variable salt intake, rendering them more susceptible to atherosclerosis., Methods: Apolipoprotein E-deficient (ApoE-/-) mice received standard or high-salt diet (8%) alone or in combination with fixed angiotensin II (Ang II) infusion (0.5 microg/kg per min). BP was measured using telemetry, and plaque burden was assessed in the thoracic aorta and innominate artery. We used urinary isoprostane as a marker for oxidative stress., Results: Although high-salt diet per se did not affect plaque extension, high salt combined with Ang II increased plaque area significantly in both the aorta and the innominate artery as compared with Ang II or salt alone (P < 0.05 and P < 0.01, respectively). High-salt diet did not affect BP or isoprostane levels, whereas Ang II infusion increased both BP and isoprostane levels (P < 0.05 and P < 0.01, respectively). Although high-salt diet combined with Ang II did not amplify BP, salt in combination with Ang II increased isoprostane levels further (P < 0.001 vs. Ang II alone). Ang II increases macrophage content in lesions (P < 0.05), whereas salt likely increases collagen content., Conclusion: High-salt diet per se does not influence BP in ApoE-/- mice and is only moderately atherogenic. Possibly mediated via increased oxidative stress, a high-salt diet combined with fixed high Ang II levels accelerates atherogenesis synergistically, beyond the effect of BP.

Social support and a stimulating environment have been suggested to reduce stress reactions and cardiovascular risk. The aim of this study was to assess the role of environmental enrichment and social interaction for development of atherosclerosis in atherosclerosis prone mice. Male ApoE-/- mice were divided into four groups and followed during 20 weeks: (i) enriched environment (E, n=12), (ii) deprived environment (ED, n=12), (iii) enriched environment with exercise (E-Ex, n=12) and (iv) socially deprived by individual housing (SD, n=10). Plasma lipid and cytokine concentrations were measured. Atherosclerosis was quantified in cross-sections of innominate artery and en face in thoracic aorta. Plaque area was significantly increased in SD mice in the innominate artery (P<0.05 vs. all other groups), but not in the thoracic aorta. Plasma lipids were increased in SD mice (P<0.001 vs. all for total cholesterol, P<0.05 vs. E and P<0.01 vs. ED for triglycerides). Plasma concentration of granulocyte-colony stimulating factor (G-CSF) was decreased in SD mice compared to E mice (P<0.05). Thus, social isolation increased atherosclerosis and plasma lipids in ApoE-/- mice. Reduction in plasma G-CSF levels may hamper endothelial regeneration in the atherosclerotic process. While environmental enrichment did not affect atherosclerosis, social isolation accelerated atherosclerosis.

Objective: Expression of the angiotensin type 2 receptor (AT2-receptor) occurs in many animal models of atherosclerosis. However, its expression in human plaques and its functional role remains undetermined. This study examined AT2-receptor expression in human atherosclerotic plaque and also explored its potentially important functional role in atherosclerosis., Material and Methods: We analysed carotid atherosclerotic plaques obtained from 14 Caucasian patients who had previously undergone endarterectomy for symptomatic carotid artery stenosis. Half of all subjects received treatment with an angiotensin receptor blocker (ARB) (n=7); the remaining subjects received no intervention in the renin-angiotensin system (n=7). Immunohistochemistry measured tissue expression of smooth muscle cells (a-actin), macrophages (CD68 antibody), collagen (picro-sirius), and AT2-receptor (AT2-receptor antibody)., Results: AT2-receptor expression occurred consistently in all specimens. Although cellular localisation varied, AT2-receptor expression levels correlated with macrophage levels (p<0.01). Compared to conventional treatment, ongoing ARB treatment affected neither AT2-receptor levels nor plaque composition., Conclusions: AT2-receptor is expressed in human atherosclerotic plaque. Furthermore, we detected no functionally important role of AT2-receptor expression and found no evidence that ARB treatment regulates AT2-receptor expression.

Estradiol, the major endogenous estrogen, reduces experimental atherosclerosis and metabolizes to 2-methoxyestradiol in vascular cells. Currently undergoing evaluation in clinical cancer trials, 2-methoxyestradiol potently inhibits cell proliferation independently of the classical estrogen receptors. This study examined whether 2-methoxyestradiol affects atherosclerosis development in female mice. Apolipoprotein E-deficient mice, a well-established mouse model of atherosclerosis, were ovariectomized and treated through slow-release pellets with placebo, 17beta-estradiol (6 microg/d), or 2-methoxyestradiol [6.66 microg/d (low-dose) or 66.6 microg/d (high-dose)]. After 90 d, body weight gain decreased and uterine weight increased in the high-dose but not low-dose 2-methoxyestradiol group. En face analysis showed that the fractional area of the aorta covered by atherosclerotic lesions decreased in the high-dose 2-methoxyestradiol (52%) but not in the low-dose 2-methoxyestradiol group. Total serum cholesterol levels decreased in the high- and low-dose 2-methoxyestradiol groups (19%, P < 0.05 and 21%, P = 0.062, respectively). Estradiol treatment reduced the fractional atherosclerotic lesion area (85%) and decreased cholesterol levels (42%). In conclusion, our study shows for the first time that 2-methoxyestradiol reduces atherosclerotic lesion formation in vivo. The antiatherogenic activity of an estradiol metabolite lacking estrogen receptor activating capacity may argue that trials on cardiovascular effects of hormone replacement therapy should use estradiol rather than other estrogens. Future research should define the role of 2-methoxyestradiol as a mediator of the antiatherosclerotic actions of estradiol. Furthermore, evaluation of the effects of 2-methoxyestradiol on cardiovascular disease endpoints in ongoing clinical trials is of great interest.

Human growth hormone (GH) excess is linked to increased cardiovascular morbidity and mortality. However, little is known about the effect of GH excess on atherosclerosis. We developed a new mouse model to assess the hypothesis that GH overexpression accelerates atherosclerotic lesion formation. apoE(-/-) mice were crossed with bovine GH (bGH) transgenic mice to yield apoE(-/-) mice overexpressing bGH (apoE(-/-)/bGH). The mice were fed either standard or Western diet. At 22 weeks, atherosclerotic lesion area of thoracic aorta was larger in apoE(-/-)/bGH mice compared with littermate apoE(-/-) mice fed either diet (standard: +161+/-50%, Western: +430+/-134%). Aortic sinus lesions were more severe in apoE(-/-)/bGH mice fed standard diet compared with littermate apoE(-/-) mice. apoE(-/-)/bGH mice had lower (VLDL+LDL)/HDL ratios compared with littermate apoE(-/-) mice, while systolic blood pressure was higher in apoE(-/-)/bGH mice, irrespective of diet. The levels of serum amyloid A and hepatic CRP mRNA were higher in apoE(-/-)/bGH mice than in littermate apoE(-/-) mice. In conclusion, this study shows that excess GH augments the development of atherosclerosis in apoE(-/-) mice. The mechanisms could be direct effects of GH on cellular processes in the vessel wall or the result of concomitant processes such as hypertension or a general inflammatory state.

Objective: Using an aortic constriction model in mice, we studied whether the increase in pressure or the activation of the renin-angiotensin system (RAS) and its main receptors is the main driving force for plaque progression., Methods: Male ApoE mice underwent sham surgery or placement of a suprarenal silver clip around the aorta (AoC). Half the group was treated with the selective AT1 receptor antagonist losartan (30 mg/kg per day) for 4 weeks., Results: Anesthetized mean arterial pressure (MAP) was increased in AoC mice compared to sham (106 +/- 3 versus 90 +/- 1 mmHg, P < 0.001). Losartan reduced MAP in sham mice (78 +/- 2 mmHg, P < 0.01) but not in AoC (AoC losartan 104 +/- 2 mmHg). Plasma renin concentration (PRC) was increased in AoC mice compared to sham [1.6 +/- 0.3 versus 0.8 +/- 0.2 milliGoldblatt units (mGU)/ml, P < 0.001]. Losartan treatment augmented this difference (18.7 +/- 3.7 versus 4.6 +/- 1.7 mGU/ml, P < 0.01). AT2 receptor mRNA expression was increased 5.8-fold by aortic constriction in thoracic aorta (P < 0.05) and the major site for expression of the AT2 receptor protein was within the plaques. The plaque area was increased in AoC mice compared to sham (0.61 +/- 0.09 versus 0.07 +/- 0.01%, P < 0.001); however, losartan did not alter plaque area., Conclusions: Our data do not support a role for the AT1 receptor in the progression of atherosclerosis in this model, since blockade with losartan did not alter plaque distribution. Furthermore, we found no support for the counteraction of atherogenesis by increased activity of the RAS acting on the AT2 receptor. Our data suggest that increased pressure is the main driving force for atherosclerosis in this model.

The alpha 7 nicotinic acetylcholine receptor (α7nAChR) regulates inflammation in experimental models and is expressed in human peripheral blood mononuclear cells (PBMCs) and in human atherosclerotic plaques. However, its role in regulating inflammation in patients with cardiovascular disease is unknown. This study aims to investigate whether α7nAChR stimulation can reduce the inflammatory response in PBMCs from patients with newly diagnosed coronary artery disease (CAD). Human PBMCs, extracted from patients with verified CAD (n = 38) and control participants with healthy vessels (n = 38), were challenged in vitro with lipopolysaccharide (LPS) in combination with the α7nAChR agonist PHA 568487. Cytokine levels of the supernatants were analyzed using a multiplex immunoassay. Patients in the CAD group were reexamined after 6 mo. The immune response to LPS did not differ between PBMCs from control and CAD groups. α7nAChR stimulation decreased TNFα in both control and CAD groups. The most pronounced effect of α7nAChR stimulation was observed in patients with CAD at their first visit, where 15 of 17 cytokines were decreased [IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-10, IL-12 (p70), IL-17A, G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1β, and TNFα]. In conclusion, stimulation with α7nAChR agonist PHA 568487 dampens the inflammatory response in human PBMCs. This finding suggests that the anti-inflammatory properties of the α7nAChR may have a role in treating CAD. NEW & NOTEWORTHY: The α7nAChR is an important regulator of inflammation; however, its anti-inflammatory function in patients with newly diagnosed coronary artery disease (CAD) remains unclear. We demonstrate that stimulation of α7nAChR with PHA 568487 attenuates the inflammatory response in immune cells extracted from healthy controls and patients with newly diagnosed CAD, with a more pronounced effect observed in patients with CAD. This suggests that the anti-inflammatory properties of α7nAChR may have a role in treating chronic inflammatory diseases. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to estimate the relationship between non-alcoholic fatty liver disease (NAFLD) and measures of atherosclerotic cardiovascular disease (ASCVD), and to determine to what extent such relationships are modified by metabolic risk factors. Methods: The study was conducted in the population-based Swedish CArdioPulmonary bioImage Study (SCAPIS) pilot cohort (n = 1015, age 50–64 years, 51.2% women). NAFLD was defined as computed tomography liver attenuation ≤40 Hounsfield Units, excluding other causes of liver fat. Coronary artery calcification score (CACS) was assessed using the Agatston method. Carotid plaques and intima media thickness (IMT) were measured by ultrasound. Metabolic status was based on assessments of glucose homeostasis, serum lipids, blood pressure and inflammation. A propensity score model was used to balance NAFLD and non NAFLD groups with regards to potential confounders and associations between NAFLD status and ASCVD variables in relation to metabolic status were examined by logistic and generalized linear regression models. Results: NAFLD was present in 106 (10.4%) of the subjects and strongly associated with obesity-related traits. NAFLD was significantly associated with CACS after adjustment for confounders and metabolic risk factors (OR 1.77, 95% CI 1.07–2.94), but not with carotid plaques and IMT. The strongest association between NAFLD and CACS was observed in subjects with few metabolic risk factors (n = 612 [60% of all] subjects with 0–1 out of 7 predefined metabolic risk factors; OR 5.94, 95% CI 2.13–16.6). Conclusions: NAFLD was independently associated with coronary artery calcification but not with measures of carotid atherosclerosis in this cohort. The association between NAFLD and CACS was most prominent in the metabolically healthy subjects. [ABSTRACT FROM AUTHOR]

The microbes and microbial pathways that influence host inflammatory disease progression remain largely undefined. Here, we show that variation in atherosclerosis burden is partially driven by gut microbiota and is associated with circulating levels of uric acid (UA) in mice and humans. We identify gut bacterial taxa spanning multiple phyla, including Bacillota , Fusobacteriota , and Pseudomonadota , that use multiple purines, including UA as carbon and energy sources anaerobically. We identify a gene cluster that encodes key steps of anaerobic purine degradation and that is widely distributed among gut-dwelling bacteria. Furthermore, we show that colonization of gnotobiotic mice with purine-degrading bacteria modulates levels of UA and other purines in the gut and systemically. Thus, gut microbes are important drivers of host global purine homeostasis and serum UA levels, and gut bacterial catabolism of purines may represent a mechanism by which gut bacteria influence health. [Display omitted] • Fecal transplant modulates atherosclerosis and blood uric acid levels • A bacterial gene cluster allows anaerobic growth on multiple purines • Genes required for purine degradation are widespread among gut bacteria • Purine-degrading bacteria modulate levels of uric acid and other purines in vivo Kasahara, Kerby et al. report that atherosclerosis burden is influenced by the gut microbiome and associated with higher blood uric acid levels. They demonstrate that specific gut bacteria lower systemic uric acid, and they identify environmental factors and a gene cluster that are required for anaerobic degradation of purines, including uric acid. [ABSTRACT FROM AUTHOR]

Background: Vascularization of atherosclerotic plaques has been linked to plaque vulnerability. The aim of this study was to test if the vascularization was increased in upstream regions of early atherosclerotic carotid plaques and also to test if the same pattern of vascularization was seen in complicated, symptomatic plaques. Methods: We enrolled 45 subjects with early atherosclerotic lesions for contrast enhanced ultrasound and evaluated the percentage of plaque area in a longitudinal ultrasound section which contained contrast agent. Contrast-agent uptake was evaluated in both the upstream and downstream regions of the plaque. We also collected carotid endarterectomy specimens from 56 subjects and upstream and downstream regions were localized using magnetic resonance angiography and analyzed using histopathology and immunohistochemistry. Results: Vascularization was increased in the upstream regions of early carotid plaques compared with downstream regions (30% vs. 23%, p = 0.033). Vascularization was also increased in the upstream regions of advanced atherosclerotic lesions compared with downstream regions (4.6 vs. 1.4 vessels/mm2, p = 0.001) and was associated with intra-plaque hemorrhage and inflammation. Conclusions: Vascularization is increased in the upstream regions of both early and advanced plaques and is in advanced lesions mainly driven by inflammation. [ABSTRACT FROM AUTHOR]

Atherosclerotic cardiovascular diseases are the leading causes of morbidity and mortality worldwide. We have previously shown that arachidonate 15-lipoxygenase B (ALOX15B) is highly expressed in atherosclerotic carotid plaques, and elucidation of mechanisms downstream of activated lipoxygenases may be relevant to our understanding of the genesis of atherosclerotic diseases. We examined 120 carotid plaques from patients with symptomatic carotid artery stenosis and showed that the extent of ALOX15B staining was significantly increased in carotid plaques with thrombosis. Impedance aggregometry analyses showed that the ALOX15B enzyme products 15-HETE and 15-HPETE increased platelet aggregation. By using a calibrated automatic thrombin assay, we showed that the ALOX15B products also increased both peak levels of thrombin and the total endogenous thrombin potential. Moreover, platelet aggregation was increased by addition of cell lysates from ischemic human macrophages, whereas platelet aggregation was reduced after knockdown of ALOX15B in human macrophages. Our data show that ALOX15B expression in human carotid plaques is associated with thrombus formation and that enzyme products of ALOX15B increase platelet aggregation and thrombin generation. We therefore propose that activated ALOX15B in macrophages may play a role in the induction of atherothrombotic events by increasing platelet aggregation and thrombin generation. [ABSTRACT FROM AUTHOR]

Objectives There is currently widespread exposure to the toxic metal cadmium through the diet as well as through smoking, and it has been suggested that cadmium exposure may increase the risk of cardiovascular disease. Here we examined whether cadmium exposure is associated with prevalence and growth of atherosclerotic plaques in the carotid arteries. Design and subjects The analyses were performed in a screening-based cohort of 64-year-old Caucasian women with stratified, random selection to groups with normal glucose tolerance, impaired glucose tolerance and diabetes ( n = 599). We measured cadmium concentrations in blood and urine at baseline. In addition, we performed ultrasound examination to determine the prevalence and area of atherosclerotic plaques in the carotid arteries and assessed smoking history and other cardiovascular risk factors at baseline and at a follow-up examination after a mean of 5.4 years. Results At baseline, blood cadmium levels were associated with increased risk of plaque and a large plaque area after adjustment for confounders. In women who had never smoked, blood cadmium levels correlated positively with plaque area at baseline. The occurrence of large plaques and the change in plaque area at follow-up were associated with blood and creatinine-corrected urinary cadmium concentrations at baseline after adjustment for confounders. Blood and urine cadmium levels added information to established cardiovascular risk factors in predicting progress of atherosclerosis. Conclusions We have shown that cadmium levels in blood and urine are independent factors associated with the development of atherosclerotic plaques at baseline as well as prospectively. This novel observation emphasizes the need to consider cadmium as a pro-atherogenic pollutant. [ABSTRACT FROM AUTHOR]

Atherosclerotic lesions are characterized by lipid-loaded macrophages (foam cells) and hypoxic regions. Although it is well established that foam cells are produced by uptake of cholesterol from oxidized LDL, we previously showed that hypoxia also promotes foam cell formation even in the absence of exogenous lipids. The hypoxia-induced lipid accumulation results from increased triglyceride biosynthesis but the exact mechanism is unknown. Our aim was to investigate the importance of glucose in promoting hypoxia-induced de novo lipid synthesis in human macrophages. In the absence of exogenous lipids, extracellular glucose promoted the accumulation of Oil Red O-stained lipid droplets in human monocyte-derived macrophages in a concentration-dependent manner. Lipid droplet accumulation was higher in macrophages exposed to hypoxia at all assessed concentrations of glucose. Importantly, triglyceride synthesis from glucose was increased in hypoxic macrophages. GLUT3 was highly expressed in macrophage-rich and hypoxic regions of human carotid atherosclerotic plaques and in macrophages isolated from these plaques. In human monocyte-derived macrophages, hypoxia increased expression of both GLUT3 mRNA and protein, and knockdown of GLUT3 with siRNA significantly reduced both glucose uptake and lipid droplet accumulation. In conclusion, we have shown that hypoxia-induced increases in glucose uptake through GLUT3 are important for lipid synthesis in macrophages, and may contribute to foam cell formation in hypoxic regions of atherosclerotic lesions [ABSTRACT FROM AUTHOR]

We examined whether high-sensitivity C-reactive protein (hsCRP) ≥2.0 mg/L was associated with increased intima-media thickness (IMT), plaque burden, and plaque echolucency in carotid arteries. Women (n = 635) from a population sample of 64-year-old females with varying degrees of glucose tolerance underwent risk factor assessment, measurement of hsCRP, and ultrasound examinations of the carotid arteries. Participants with hsCRP levels ≥2.0 mg/L had elevated carotid bulb IMT independently of other cardiovascular risk factors compared with those with hsCRP <2.0 mg/L. The participants with plaques in the highhsCRP group had larger total plaque area compared to those with plaque in the lower hsCRP group. Plaque echolucency did not differ between groups. High-sensitivity CRP levels ≥2.0 mg/L were accompanied by elevated IMT in the carotid bulbs independently of other cardiovascular risk factors. Total plaque area was larger among women with plaques in the high hsCRP group versus the lower hsCRP group. [ABSTRACT FROM PUBLISHER]

Background: The heterogeneous structure of carotid atherosclerotic plaques may be better understood if it is related to blood flow variations, influencing gene expression and cellular functions. Upstream of the maximum stenosis there is laminar blood flow and high shear stress, downstream there is turbulence and low shear stress. We studied if these variations were associated with differences in plaque morphology and composition between sites located up- and downstream of the maximum stenosis in symptomatic carotid plaques. Methods: Patients with symptomatic carotid stenosis were examined with magnetic resonance angiography to localize the maximum stenosis in-vivo, prior to endarterectomy. In 41 endarterectomized specimens, transverse tissue sections prepared up- and downstream of the maximum stenosis were compared using histopathology and immunohistochemistry. Results: The location of maximum stenosis relative the carotid bifurcation varied considerably between plaques. Compared with the downstream side, the upstream side of the stenosis had higher incidence of severe lesions with cap rupture and intraplaque hemorrhage, more macrophages, less smooth muscle cells and more collagen. Conclusions: The up- and downstream sides of symptomatic carotid plaques differed in plaque morphology and composition. This implies that the intraplaque location of sampling sites may be a confounding factor in studies of atherosclerotic plaques. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Social support and a stimulating environment have been suggested to reduce stress reactions and cardiovascular risk. The aim of this study was to assess the role of environmental enrichment and social interaction for development of atherosclerosis in atherosclerosis prone mice. Male ApoE- / - mice were divided into four groups and followed during 20 weeks: (i) enriched environment (E, n = 12), (ii) deprived environment (ED, n = 12), (iii) enriched environment with exercise (E-Ex, n = 12) and (iv) socially deprived by individual housing (SD, n = 10). Plasma lipid and cytokine concentrations were measured. Atherosclerosis was quantified in cross-sections of innominate artery and en face in thoracic aorta. Plaque area was significantly increased in SD mice in the innominate artery (P < 0.05 vs. all other groups), but not in the thoracic aorta. Plasma lipids were increased in SD mice (P < 0.001 vs. all for total cholesterol, P < 0.05 vs. E and P < 0.01 vs. ED for triglycerides). Plasma concentration of granulocyte-colony stimulating factor (G-CSF) was decreased in SD mice compared to E mice (P < 0.05). Thus, social isolation increased atherosclerosis and plasma lipids in ApoE- / - mice. Reduction in plasma G-CSF levels may hamper endothelial regeneration in the atherosclerotic process. While environmental enrichment did not affect atherosclerosis, social isolation accelerated atherosclerosis. [ABSTRACT FROM AUTHOR]

Abstract: Atherosclerotic stenotic and nonstenotic plaques of the carotid artery with low echogenicity have been shown to be associated with cardiovascular disease. The aim was to develop a new method for semiautomated ultrasound image analysis to classify nonstenotic carotid plaques, evaluate cases with multiple plaques and examine the association between a new image analysis feature of echogenicity and predictors of cardiovascular disease. The new image analysis feature, percentage white (PW), represents the fraction of bright structures inside a plaque and is integrated in an objective semiautomated method to evaluate echogenicity (SAMEE) in carotid plaques. PW was constructed to take into account overall echogenicity of the image as well as noise surrounding the plaque. Consecutive ultrasound examinations of carotid plaques from a population-based screening of 64-year-old women with varying risk for cardiovascular disease were selected for the present project; 92 far-wall and 47 near-wall plaques were used as a training dataset to develop the SAMEE algorithm with visual classification according to Gray-Weale as reference; 273 plaques were used to validate the method. All plaques were included in an analysis relating predictors of cardiovascular to average PW in all plaques, PW in the biggest plaque and to the plaque with lowest PW in each subject, respectively. In the training dataset the intermethodological variability between SAMEE and visual classification showed a κ of 0.78 and a sensitivity and specificity of 96% and 81%, respectively. In the validation set, SAMEE and visual classification showed a κ of 0.77, a sensitivity of 96% and a specificity of 80%. The reproducibility of PW was high, evidenced by r = 0.96 and CV = 9.85% at repeated examinations. Average PW values were associated with several predictors of cardiovascular risk: lipoprotein (a), HbA1c, blood glucose, apolipoproteinB/apolipoproteinA-I; and associated negatively with the levels of adiponectin and apolipoprotein A-I. In conclusion, PW integrated within a SAMEE is a new feature for assessment of echogenicity in carotid plaques and shows excellent reproducibility and agreement with visual assessment. (E-mail: ulrica.prahl@wlab.gu.se). [Copyright &y& Elsevier]

Background and aims Recent evidence suggests that the microbiota may be considered as an environmental factor that contributes to the development of atherosclerosis. Periodontal disease has been associated with cardio- and cerebrovascular events, and inflammation in the periodontium is suggested to increase the systemic inflammatory level of the host, which may in turn influence plaque composition and rupture. We previously showed that bacteria from the oral cavity and the gut could be found in atherosclerotic plaques. Methods To elucidate whether the oral microbiota composition differed between patients with asymptomatic and symptomatic atherosclerosis we performed pyrosequencing of the oral microbiota of 92 individuals including patients with asymptomatic and symptomatic atherosclerosis and control individuals without carotid plaques or previous stroke or myocardial infarction. Results The overall microbial structure was similar in controls and atherosclerosis patients, but patients with symptomatic atherosclerosis had higher relative abundance of Anaeroglobus (mean 0.040% (SD 0.049)) than the control group (0.010% (SD 0.028)) ( P = 0.03). Using linear regression analysis, we found that Parvimonas associated positively with uCRP and Capnocytophaga , Catonella and Lactobacillus associated with blood lipid markers. In conclusion, abundance of Anaeroglobus in the oral cavity could be associated with symptomatic atherosclerosis. [ABSTRACT FROM AUTHOR]

Despite firm evidence for an association between long-term ambient air pollution exposure and cardiovascular morbidity and mortality, results from epidemiological studies on the association between air pollution exposure and atherosclerosis have not been consistent. We investigated associations between long-term low-level air pollution exposure and coronary atherosclerosis. We performed a cross-sectional analysis in the large Swedish CArdioPulmonary bioImaging Study (SCAPIS, n = 30 154), a random general population sample. Concentrations of total and locally emitted particulate matter <2.5 μm (PM 2.5), <10 μm (PM 10), and nitrogen oxides (NO x) at the residential address were modelled using high-resolution dispersion models. We estimated associations between air pollution exposures and segment involvement score (SIS), coronary artery calcification score (CACS), number of non-calcified plaques (NCP), and number of significant stenoses, using ordinal regression models extensively adjusted for potential confounders. Median 10-year average PM 2.5 exposure was 6.2 μg/m3 (range 3.5–13.4 μg/m3). 51 % of participants were women and 51 % were never-smokers. None of the assessed pollutants were associated with a higher SIS or CACS. Exposure to PM 2.5 was associated with NCP (adjusted OR 1.34, 95 % CI 1.13, 1.58, per 2.05 μg/m3). Associations with significant stenoses were inconsistent. In this large, middle-aged general population sample with low exposure levels, air pollution was not associated with measures of total burden of coronary atherosclerosis. However, PM 2.5 appeared to be associated with a higher prevalence of non-calcified plaques. The results suggest that increased risk of early-stage atherosclerosis or rupture, but not increased total atherosclerotic burden, may be a pathway for long-term air pollution effects on cardiovascular disease. [Display omitted] • Firm evidence shows that air pollution is a risk factor for cardiovascular disease. • However, studies of the association with atherosclerosis remain inconclusive. • We assessed air pollution and atherosclerosis in a large Swedish multi-city study. • Air pollution was associated with non-calcified plaques but not total plaque burden. • Our results may indicate an association with early or vulnerable atherosclerosis. [ABSTRACT FROM AUTHOR]

Background and Aims The general population is exposed to cadmium through diet and smoking. Cadmium is pro-atherogenic and pro-inflammatory in experimental and observational studies. Cadmium levels in blood and carotid plaque endarterectomies correlate. Cadmium concentrations are much higher in plaque-areas that most frequently rupture. Here we investigated if blood cadmium concentrations are associated with macrophage density and the accumulation of CD14 as indicator of macrophage activation by lipopolysaccharide (LPS) in endarterectomies from patients with symptomatic carotid plaques. Methods Endarterectomies from ninety nine patients were fixed in formalin, embedded in paraffin, serially sectioned and stained for assessment of morphology. As predefined, the two section levels with most prevalent plaque rupture were used for further analyses. Macrophages were assessed as area of staining for CD68 (%). Blood cadmium was measured with ICP-MS. Results The CD68 median [25,75 percentiles] from the average of both sections were higher in cadmium tertile 3 than in tertile 1 (9.8 [4.9,16.1] % and 3.8 (0.6,12.4) %, p = 0.017). This difference remained in a multiple linear regression analysis with 10 log meanCD68 as dependent variable and adjustment for sex, age, smoking, statin treatment, index event, time between event and surgery (beta coefficient 0.44 [95% CI 0.05–0.87]. CD14 was not associated with blood cadmium. Conclusions The results showed that blood cadmium was associated with proinflammatory macrophage density in the sections of carotid plaques with most frequent rupture, previously shown to contain most cadmium. No association between cadmium and LPS-mediated macrophage-activation was found. Cadmium exposure may promote plaque inflammation. [ABSTRACT FROM AUTHOR]

Abstract: Background: Haptoglobin polymorphism generates three common human genotypes: Hp1-1, Hp2-1 and Hp2-2. Among subjects with diabetes, Hp2-2 is associated with an elevated risk to develop cardiovascular disease. The impact of haptoglobin genotype on subclinical carotid atherosclerosis is not known. We hypothesized that Hp2-2 was associated with increased occurrence of carotid atherosclerosis in subjects with diabetes. Methods: We studied a population-based sample of 64-year old women with diabetes (n =226), either established diabetes known before study entry (n =116) or new diabetes detected at study screening (n =110). Haptoglobin genotype was determined by PCR. Carotid atherosclerosis was assessed by ultrasound imaging. Results: In the entire diabetes cohort, no differences were observed in carotid intima-media thickness (IMT) or plaque prevalence between the genotype groups. However, among those with established diabetes, Hp2-2 was associated with higher plaque prevalence and larger carotid IMT compared with the Hp2-1 and Hp1-1 genotypes. Common cardiovascular risk factors did not differ between the genotype groups. Conclusions: The Hp2-2 genotype was associated with increased occurrence of subclinical carotid atherosclerosis in 64-year old women with established diabetes. This association was not explained by traditional risk factors for cardiovascular disease. These results extend previous observations that Hp2-2 is associated with clinical cardiovascular disease in diabetes. [Copyright &y& Elsevier]

Introduction: The European guidelines recommend using the Systematic COronary Risk Evaluation (SCORE) charts to assess the absolute risk of fatal atherosclerotic disease in apparently healthy persons in order to guide risk factor treatment. It is not clear if the SCORE algorithm is useful for identifying the prevalence of subclinical atherosclerosis in an unselected population. In this first interim analysis of the large Swedish CArdioPulmonary bioImage Study (SCAPIS) cohort, we explored the association between SCORE and prevalent calcification of the coronary arteries or prevalent plaques in the carotid arteries. Hypothesis: The SCORE estimated risk is associated with prevalent subclinical atherosclerosis in people without established cardiovascular disease or diabetes mellitus. Methods: We randomly invited individuals aged 50-64 years from the general population of six Swedish university cities. The study population included between November 2013 and December 2016 consisted of 13,397 participants, age 57 (SD 4.3) years; 46% males, after exclusion of subjects with; prevalent cardiovascular disease or diabetes mellitus; and missing data (n=2,318 and 589, respectively). In addition to the determination of the traditional cardiovascular risk factors, we recorded data from a computed tomography scan of the heart and ultrasonography of the carotid arteries. We analyzed coronary artery calcium score as present or absent coronary calcification. Presence of plaques in any of the carotid arteries were recorded. The individual SCORE value was calculated and log transformed before analyses. Results: Coronary calcification was present in 41% and plaques in any of the carotid arteries in 56% of the participants in the study population. One unit higher SCORE was associated with an odds ratio (OR) of 2.75 (95% CI, 2.62 to 2.90) for having coronary calcification, and with an OR of 1.85 (95% CI, 1.77 to 1.94) for having ≥1 carotid plaque on any side. Conclusion: In conclusion, SCORE estimated risk was associated with prevalent subclinical atherosclerosis in two major vascular beds in a general population sample without established cardiovascular disease or diabetes mellitus. [ABSTRACT FROM AUTHOR]