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Frontiers in Immunology 2022Cardiovascular diseases, the notorious killer, are mainly caused by atherosclerosis (AS) characterized by lipids, cholesterol, and iron overload in plaques. Macrophages...
Cardiovascular diseases, the notorious killer, are mainly caused by atherosclerosis (AS) characterized by lipids, cholesterol, and iron overload in plaques. Macrophages are effector cells and accumulate to the damaged and inflamed sites of arteries to internalize native and chemically modified lipoproteins to transform them into cholesterol-loaded foam cells. Foam cell formation is determined by the capacity of phagocytosis, migration, scavenging, and the features of phenotypes. Macrophages are diverse, and the subsets and functions are controlled by their surrounding microenvironment. Generally, macrophages are divided into classically activated (M1) and alternatively activated (M2). Recently, intraplaque macrophage phenotypes are recognized by the stimulation of CXCL4 (M4), oxidized phospholipids (Mox), hemoglobin/haptoglobin complexes [HA-mac/M(Hb)], and heme (Mhem). The pro-atherogenic or anti-atherosclerotic phenotypes of macrophages decide the progression of AS. Besides, apoptosis, necrosis, ferroptosis, autophagy and pyrotopsis determine plaque formation and cardiovascular vulnerability, which may be associated with macrophage polarization phenotypes. In this review, we first summarize the three most popular hypotheses for AS and find the common key factors for further discussion. Secondly, we discuss the factors affecting macrophage polarization and five types of macrophage death in AS progression, especially ferroptosis. A comprehensive understanding of the cellular and molecular mechanisms of plaque formation is conducive to disentangling the candidate targets of macrophage-targeting therapies for clinical intervention at various stages of AS.
Topics: Atherosclerosis; Foam Cells; Humans; Macrophage Activation; Macrophages; Plaque, Atherosclerotic
PubMed: 35432323
DOI: 10.3389/fimmu.2022.843712 -
Pharmacology & Therapeutics Apr 2019Atherosclerosis, the principal cause of cardiovascular death worldwide, is a pathological disease characterized by fibro-proliferation, chronic inflammation, lipid...
Atherosclerosis, the principal cause of cardiovascular death worldwide, is a pathological disease characterized by fibro-proliferation, chronic inflammation, lipid accumulation, and immune disorder in the vessel wall. As the atheromatous plaques develop into advanced stage, the vulnerable plaques are prone to rupture, which causes acute cardiovascular events, including ischemic stroke and myocardial infarction. Emerging evidence has suggested that atherosclerosis is also an epigenetic disease with the interplay of multiple epigenetic mechanisms. The epigenetic basis of atherosclerosis has transformed our knowledge of epigenetics from an important biological phenomenon to a burgeoning field in cardiovascular research. Here, we provide a systematic and up-to-date overview of the current knowledge of three distinct but interrelated epigenetic processes (including DNA methylation, histone methylation/acetylation, and non-coding RNAs), in atherosclerotic plaque development and instability. Mechanistic and conceptual advances in understanding the biological roles of various epigenetic modifiers in regulating gene expression and functions of endothelial cells (vascular homeostasis, leukocyte adhesion, endothelial-mesenchymal transition, angiogenesis, and mechanotransduction), smooth muscle cells (proliferation, migration, inflammation, hypertrophy, and phenotypic switch), and macrophages (differentiation, inflammation, foam cell formation, and polarization) are discussed. The inherently dynamic nature and reversibility of epigenetic regulation, enables the possibility of epigenetic therapy by targeting epigenetic "writers", "readers", and "erasers". Several Food Drug Administration-approved small-molecule epigenetic drugs show promise in pre-clinical studies for the treatment of atherosclerosis. Finally, we discuss potential therapeutic implications and challenges for future research involving cardiovascular epigenetics, with an aim to provide a translational perspective for identifying novel biomarkers of atherosclerosis, and transforming precision cardiovascular research and disease therapy in modern era of epigenetics.
Topics: Animals; Atherosclerosis; Epigenesis, Genetic; Humans; Immunity; RNA, Untranslated; Risk Factors
PubMed: 30439455
DOI: 10.1016/j.pharmthera.2018.11.003 -
Cureus Apr 2023The main risk factor for atherosclerotic cardiovascular disease is smoking. Nicotine and carbon monoxide are two dangerous substances that are found in cigarette smoke.... (Review)
Review
The main risk factor for atherosclerotic cardiovascular disease is smoking. Nicotine and carbon monoxide are two dangerous substances that are found in cigarette smoke. The increased heart rate can have an almost instantaneous impact on the heart and blood vessels. Smoking is well known to cause oxidative stress, endanger the lining of the arteries, and accelerate the accumulation of fatty plaque in the blood vessels. It raises the danger of sudden thrombotic events, inflammatory alterations, and low-density lipoprotein oxidation. The smoke's carbon monoxide decreases the blood's capacity to deliver oxygen, adding to the heart's stress. Notably, these risks increase when diabetes, hypertension, high cholesterol, and glucose intolerance are present. It has a detrimental effect on peripheral blood vessels, raising the possibility of thromboangiitis obliterans. Stroke risk is known to be increased by smoking. As compared to those who continue to smoke, those who give up smoking have a much longer life expectancy. Chronic cigarette smoking has been shown to affect the macrophages' ability to remove cholesterol. Abstinence from smoking enhances the function of high-density lipoproteins and cholesterol efflux, lowering the risk of plaque buildup. In this review, we present the most recent information regarding the causal relationship between smoking and cardiovascular health as well as the long-term advantages of quitting.
PubMed: 37234135
DOI: 10.7759/cureus.38073 -
Cardiovascular Diabetology Jul 2023The TyG index is an indicator of insulin resistance (IR), which is associated with the development and prognosis of cardiovascular disease. This study aimed to summarize... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The TyG index is an indicator of insulin resistance (IR), which is associated with the development and prognosis of cardiovascular disease. This study aimed to summarize the relationship between the TyG index and the risk, severity, and prognosis of coronary artery disease (CAD) by performing a systematic review and meta-analysis.
METHODS
The PubMed, EMBASE, The Cochrane Library, and Web of Science databases were searched for articles published from inception until May 1, 2023. Cross-sectional studies, retrospective or prospective cohort studies recruiting patients with CAD were included. For the analysis of CAD severity, the outcomes were coronary artery calcification, coronary artery stenosis, coronary plaque progression, multi-vessel CAD, and in-stent re-stenosis. For the analysis of CAD prognosis, the primary outcome was major adverse cardiovascular events (MACE).
RESULTS
Forty-one studies were included in this study. Compared to patients with the lowest TyG index, those with the highest TyG index had a higher CAD risk [odds ratio (OR): 1.94, 95% confidence interval (CI) 1.20-3.14, I = 91%, P = 0.007]. Additionally, these patients were more likely to have stenotic coronary arteries (OR: 3.49, 95% CI 1.71-7.12, I = 0%, P = 0.0006), progressed plaques (OR: 1.67, 95% CI 1.28-2.19, I = 0%, P = 0.002), and with more vessels involved (OR: 2.33, 95% CI 1.59-3.42, I = 0%, P < 0.0001). When calculated as a categorized variable, it appears that acute coronary syndrome (ACS) patients with higher TyG index levels may have a higher incidence rate of MACE [hazard ratio (HR): 2.09, 95% CI 1.68-2.62, I = 87%, P < 0.00001], whereas chronic coronary syndrome (CCS) or stable CAD patients with higher TyG index levels showed a trend towards an increased incidence rate of MACE (HR: 1.24, 95% CI 0.96-1.60, I = 85%, P = 0.09). When calculated as a continuous variable, ACS patients had an HR of 2.28 per 1-unit/1-standard deviation increment of the TyG index (95% CI 1.44-3.63, I = 95%, P = 0.0005). Similarly, CCS or stable CAD patients had an HR of 1.49 per 1-unit/1-standard deviation increment of the TyG index (95% CI 1.21-1.83, I = 75%, P = 0.0001). Myocardial infarction with non-obstructive coronary arteries patients had an HR of 1.85 per 1-unit increment of the TyG index (95% CI 1.17-2.93, P = 0.008).
CONCLUSIONS
The TyG index is a simple new synthetic index that has been proven to be a valuable tool in the whole-course management of CAD patients. Patients with higher TyG index levels are at a higher risk of CAD, more severe coronary artery lesions, and worse prognosis compared to those with lower TyG index levels.
Topics: Humans; Coronary Artery Disease; Glucose; Retrospective Studies; Triglycerides; Prospective Studies; Cross-Sectional Studies; Risk Factors; Risk Assessment; Prognosis; Plaque, Atherosclerotic; Acute Coronary Syndrome; Blood Glucose; Biomarkers
PubMed: 37415168
DOI: 10.1186/s12933-023-01906-4 -
Frontiers in Cardiovascular Medicine 2023Individuals diagnosed with atherosclerotic cardiovascular disease (ACD) are exposed to an increased risk of cardiovascular events. Reducing low-density lipoprotein... (Review)
Review
INTRODUCTION
Individuals diagnosed with atherosclerotic cardiovascular disease (ACD) are exposed to an increased risk of cardiovascular events. Reducing low-density lipoprotein cholesterol (LDL-C) levels has been established as an effective approach to mitigate these risks. However, a comprehensive and up-to-date meta-analysis investigating the LDL-C-lowering effectiveness and the impact on coronary atherosclerotic plaque compositions of Ezetimibe has been lacking.
METHODS
We conducted a systematic review by meticulously analyzing databases such as MEDLINE, EMBASE, and the Cochrane CENTRAL for randomized controlled trials that evaluated the efficacy of ezetimibe in lowering LDL-C levels and its influence on coronary atherosclerotic plaques among individuals with ACD. This review encompassed studies available until August 1, 2023. In our analysis, we employed the weighted mean difference (WMD) as the aggregated statistical measure, accompanied by the corresponding 95% confidence interval (CI).
RESULTS
We encompassed a total of 20 eligible studies. Our findings unveiled that the combined therapy involving ezetimibe alongside statins led to a more substantial absolute decrease in LDL-C in comparison to using statins alone. This difference in means amounted to (-14.06 mg/dl; 95% CI -18.0 to -10.0; = 0.0001). Furthermore, upon conducting subgroup analyses, it became evident that the intervention strategies proved effective in diminishing the volume of dense calcification (DC) in contrast to the control group.
CONCLUSIONS
Our study findings indicate that the inclusion of ezetimibe in conjunction with statin therapy leads to a modest yet meaningful additional reduction in LDL-C levels when compared to using statins in isolation. Importantly, the introduction of ezetimibe resulted in a significant decrease in the volume of DC. However, it is worth noting that further investigation is warranted to delve deeper into this phenomenon.
PubMed: 38075958
DOI: 10.3389/fcvm.2023.1269172 -
Brain Circulation 2022Carotid stenosis is an important contributor to ischemic stroke risk with resultant significant impact on neurological disability and death in adults and with worldwide... (Review)
Review
Carotid stenosis is an important contributor to ischemic stroke risk with resultant significant impact on neurological disability and death in adults and with worldwide implications. Management of carotid stenosis is impacted by whether there are associated symptoms along with the degree of stenosis. Understanding of the pathogenesis of carotid atherosclerosis or stenosis is important in management of carotid stenosis. Atherosclerotic plaque formation is a chronic insidious process with a number of potential contributors to the formation of such a plaque. The definition of atherosclerosis is not simply limited to abnormal deposition of lipid but also includes a chronic, complex, inflammatory process. Molecularly, in atherosclerosis, there is decreasing nitric oxide (NO) bioavailability, activity and/or expression of endothelial NO synthase, or increasing degradation of NO secondary to enhanced superoxide production. These above changes cause endothelial dysfunction leading to formation of foam cell followed by formation on lipid plaque. After lipid plaque formation, stable or unstable atherosclerotic plaque is formed depending on the calcium deposition over the lipid plaque. It continues to be clearly established that carotid intervention for symptomatic high-grade carotid stenosis is best managed with intervention either by carotid endarterectomy or carotid stenting. However, asymptomatic carotid stenosis is the subject of considerable controversy in terms of optimal management. This review of carotid atherosclerosis is an attempt to incorporate the information provided by more recent studies on pathogenesis and management which may help in the decision-making process for optimal management for protection against stroke.
PubMed: 36267431
DOI: 10.4103/bc.bc_36_22 -
Stroke Jan 2015Ultrasonographic plaque echolucency has been studied as a stroke risk marker in carotid atherosclerotic disease. We performed a systematic review and meta-analysis to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND AND PURPOSE
Ultrasonographic plaque echolucency has been studied as a stroke risk marker in carotid atherosclerotic disease. We performed a systematic review and meta-analysis to summarize the association between ultrasound-determined carotid plaque echolucency and future ipsilateral stroke risk.
METHODS
We searched the medical literature for studies evaluating the association between carotid plaque echolucency and future stroke in asymptomatic patients. We included prospective observational studies with stroke outcome ascertainment after baseline carotid plaque echolucency assessment. We performed a meta-analysis and assessed study heterogeneity and publication bias. We also performed subgroup analyses limited to patients with stenosis ≥50%, studies in which plaque echolucency was determined via subjective visual interpretation, studies with a relatively lower risk of bias, and studies published after the year 2000.
RESULTS
We analyzed data from 7 studies on 7557 subjects with a mean follow-up of 37.2 months. We found a significant positive relationship between predominantly echolucent (compared with predominantly echogenic) plaques and the risk of future ipsilateral stroke across all stenosis severities (0% to 99%; relative risk, 2.31; 95% confidence interval, 1.58-3.39; P<0.001) and in subjects with ≥50% stenosis (relative risk, 2.61; 95% confidence interval, 1.47-4.63; P=0.001). A statistically significant increased relative risk for future stroke was preserved in all additional subgroup analyses. No statistically significant heterogeneity or publication bias was present in any of the meta-analyses.
CONCLUSIONS
The presence of ultrasound-determined carotid plaque echolucency provides predictive information in asymptomatic carotid artery stenosis beyond luminal stenosis. However, the magnitude of the increased risk is not sufficient on its own to iden tify patients likely to benefit from surgical revascularization.
Topics: Asymptomatic Diseases; Carotid Artery Diseases; Carotid Stenosis; Humans; Plaque, Atherosclerotic; Risk Assessment; Stroke; Ultrasonography
PubMed: 25406150
DOI: 10.1161/STROKEAHA.114.006091 -
Frontiers in Cardiovascular Medicine 2023Carotid atherosclerotic plaque is an important independent risk factor for stroke. Apolipoprotein E (APOE) influences cholesterol levels and certain isoforms are...
INTRODUCTION
Carotid atherosclerotic plaque is an important independent risk factor for stroke. Apolipoprotein E (APOE) influences cholesterol levels and certain isoforms are associated with increased carotid atherosclerosis, though the exact association between APOE and carotid plaque is uncertain. The study aimed to evaluate the association between APOE and carotid plaque.
METHODS
A systematic review was performed to retrieve all studies which examined the association between carotid plaque and APOE. This study was conducted in accordance with the PRISMA guidelines. Independent readers extracted the relevant data from each study including the type of imaging assessment, plaque definition, frequency of APOE E4 carrier status and type of genotyping. Meta-analyses with an assessment of study heterogeneity and publication bias were performed. Results were presented in a forest plot and summarized using a random-effects model.
RESULTS
After screening 838 studies, 17 studies were included for systematic review. A meta-analysis of 5 published studies showed a significant association between 4 homozygosity and carotid plaque [odds ratio (OR), 1.53; 95% CI, 1.16, 2.02; = .003]. Additionally, there was a significant association between patients possessing at least one 4 allele, heterozygotes or homozygotes, and carotid plaque (OR, 1.25; 95% CI, 1.03, 1.52; = .03). Lastly, there was no association between 4 heterozygosity and carotid plaque (OR, 1.08; 95% CI, 0.93, 1.26; = .30).
CONCLUSION
APOE 4 allele is significantly associated with extracranial carotid atherosclerotic plaque, especially for homozygous individuals.
PubMed: 38034385
DOI: 10.3389/fcvm.2023.1155916 -
Journal of the American Heart... Aug 2016Gadolinium enhancement on high-resolution magnetic resonance imaging (MRI) has been proposed as a marker of inflammation and instability in intracranial atherosclerotic... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Gadolinium enhancement on high-resolution magnetic resonance imaging (MRI) has been proposed as a marker of inflammation and instability in intracranial atherosclerotic plaque. We performed a systematic review and meta-analysis to summarize the association between intracranial atherosclerotic plaque enhancement and acute ischemic stroke.
METHODS AND RESULTS
We searched the medical literature to identify studies of patients undergoing intracranial vessel wall MRI for evaluation of intracranial atherosclerotic plaque. We recorded study data and assessed study quality, with disagreements in data extraction resolved by a third reader. A random-effects odds ratio was used to assess whether, in any given patient, cerebral infarction was more likely in the vascular territory supplied by an artery with MRI-detected plaque enhancement as compared to territory supplied by an artery without enhancement. We calculated between-study heterogeneity using the Cochrane Q test and publication bias using the Begg-Mazumdar test. Eight articles published between 2011 and 2015 met inclusion criteria. These studies provided information about plaque enhancement characteristics from 295 arteries in 330 patients. We found a significant positive relationship between MRI enhancement and cerebral infarction in the same vascular territory, with a random effects odds ratio of 10.8 (95% CI 4.1-28.1, P<0.001). No significant heterogeneity (Q=11.08, P=0.14) or publication bias (P=0.80) was present.
CONCLUSIONS
Intracranial plaque enhancement on high-resolution vessel wall MRI is strongly associated with ischemic stroke. Evaluation for plaque enhancement on MRI may be a useful test to improve diagnostic yield in patients with ischemic strokes of undetermined etiology.
Topics: Aged; Aged, 80 and over; Brain Ischemia; Cerebral Infarction; Contrast Media; Female; Gadolinium; Humans; Intracranial Arteriosclerosis; Magnetic Resonance Angiography; Male; Middle Aged; Plaque, Atherosclerotic; Prospective Studies; Retrospective Studies; Stroke
PubMed: 27528408
DOI: 10.1161/JAHA.116.003816 -
Stroke Feb 2023Over the last decades, several individual studies on sex differences in carotid atherosclerosis have been performed covering a wide range of plaque characteristics and... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Over the last decades, several individual studies on sex differences in carotid atherosclerosis have been performed covering a wide range of plaque characteristics and including different populations. This systematic review and meta-analysis aims to summarize previously reported results on sex differences in carotid atherosclerosis and present a roadmap explaining next steps needed for implementing this knowledge in clinical practice.
METHODS
We systematically searched PubMed, Embase, Web of Science, Cochrane Central, and Google Scholar for eligible studies including both male and female participants reporting prevalence of imaging characteristics of carotid atherosclerosis and meta-analyzed these studies. Studies had to report at least the following: (1) calcifications; (2) lipid-rich necrotic core; (3) intraplaque hemorrhage; (4) thin-or-ruptured fibrous cap; (5) plaque ulceration; (6) degree of stenosis; (7) plaque size; or (8) plaque inflammation. We prespecified which imaging modalities had to be used per plaque characteristic and excluded ultrasonography.
RESULTS
We included 42 articles in our meta-analyses (ranging from 2 through 23 articles per plaque characteristic). Men had more frequently a larger plaque compared to women and, moreover, had more often plaques with calcifications (odds ratio=1.57 [95% CI, 1.23-2.02]), lipid-rich necrotic core (odds ratio=1.87 [95% CI, 1.36-2.57]), and intraplaque hemorrhage (odds ratio=2.52 [95% CI, 1.74-3.66]), or an ulcerated plaque (1.81 [95% CI, 1.30-2.51]). Furthermore, we found more pronounced sex differences for lipid-rich necrotic core in symptomatic opposed to asymptomatic participants.
CONCLUSIONS
In this systematic review and meta-analysis, we demonstrate convincing evidence for sex differences in carotid atherosclerosis. All kinds of plaque features-plaque size, composition, and morphology-were more common or larger in men compared to women. Our results highlight that sex is an important variable to include in both study design and clinical-decision making. Further investigation of sex-specific stroke risks with regard to plaque composition is warranted.
Topics: Female; Male; Humans; Carotid Stenosis; Sex Characteristics; Magnetic Resonance Imaging; Carotid Artery Diseases; Plaque, Atherosclerotic; Hemorrhage; Calcinosis; Necrosis; Lipids; Carotid Arteries; Risk Factors
PubMed: 36444718
DOI: 10.1161/STROKEAHA.122.041046