Atherosclerotic Plaque Instability Research Articles

The Effects of the oxLDL/β2GPI/anti-β2GPI Complex on Macrophage Autophagy and its Mechanism.

Previous research has established that the oxidized low-density lipoprotein/β2-glycoprotein I/anti-β2-glycoprotein I antibody (oxLDL/β2GPI/anti-β2GPI) complex can stimulate macrophages to secrete molecules associated with atherosclerosis (AS), such as monocyte chemotactic protein 1 (MCP-1), tissue factor (TF), and tumor necrosis factor-α (TNF-α). This complex also enhances the uptake of oxLDL, thereby accelerating foam cell formation through the Toll-like receptor-4/nuclear factor kappa B (TLR4/NF-κB) pathway. Given the critical role of macrophage autophagy in the instability of vulnerable atherosclerotic plaques, it is imperative to investigate whether the oxLDL/β2GPI/anti-β2GPI complex influences macrophage autophagy in AS. This study aims to elucidate the effects and underlying mechanisms of the oxLDL/β2GPI/anti-β2GPI complex on macrophage autophagy in AS. Experiments were conducted using murine macrophage RAW264.7 cells and the human monocytic cell line THP-1. Western blot analysis was employed to determine the expressions of autophagy-associated markers and signaling pathway proteins. Autophagosomes were detected through mRFP-GFP-LC3 adenoviral transfection and transmission electron microscopy (TEM). Treatment of macrophages with the oxLDL/β2GPI/anti-β2GPI complex resulted in decreased expressions of Beclin1 and LC3 proteins, alongside an upregulation of SQSTM1/P62 protein expression. Additionally, there was a reduction in the number of autophagosomes and autolysosomes. An increase in the phosphorylation levels of phosphoinositide-3-kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) was also observed. Notably, the expressions of autophagy-associated markers were partially restored when the TLR4/NF-κB and PI3K/AKT/mTOR pathways were inhibited by their respective inhibitors. Our findings indicate that the oxLDL/β2GPI/anti-β2GPI complex inhibits macrophage autophagy in AS via the TLR4/NF-κB and PI3K/AKT/mTOR signaling pathways.

Immunothrombosis in Acute Ischemic Stroke.

Ischemic stroke is one of the leading causes of disability and mortality worldwide. Thrombosis is the main pathological process of stroke and is therefore an important therapeutic target in stroke prevention. In recent years, with the development of endovascular treatment and therefore retrieving the thrombus for further investigation, evidence is accumulating that immune cells are inextricably linked to stroke pathogenesis. Circulating immune cells have been found to induce immunothrombosis, and they actively participate in the formation of the thrombus by promoting platelet recruitment and thrombin activation. Additionally, the formation of thromboinflammation leads to increased instability of atherosclerotic plaques. We review the concepts of stroke immunothrombosis and thromboinflammation and the effect of immune cells on vessel recanalization and patient outcome. In addition, we elaborate on the possible mechanism of immune cells being activated and participating in thrombosis in ischemic stroke.

Body mass index as a contributor to the accumulation of lipidic plaque materials in statin-treated type 2 diabetic patients with coronary artery disease: sub-analysis from the OPTIMAL randomized study

Abstract Background Patients with type 2 diabetes mellitus more likely exhibit obesity. Pathophysiologically, obesity promotes a range of metabolic disturbances including insulin resistance, dyslipidemia and hypertension, in addition to the secretion of adipokines and pro-inflammatory cytokines from excessive fat accumulation. These atherogenic features may promote instability of atherosclerotic plaques, which ultimately result in elevating a risk of atherosclerotic cardiovascular disease. However, it remains to be fully elucidated how obesity affects atherosclerotic plaque features in type 2 diabetic patients with coronary artery disease (CAD). Near-infrared spectroscopy (NIRS) imaging enables to quantitatively visualize lipidic plaque materials in vivo. This imaging modality provides insights into lipidic plaque features in obese patients with type 2 diabetes mellitus. Purpose To elucidate the association of body mass index (BMI, kg/m2) with lipidic plaque materials in type 2 diabetic patients. Methods The OPTIMAL study was a prospective randomized controlled trial to evaluate the efficacy of continuous glucose monitoring (CGM) guided glycemic control on coronary atherosclerosis in statin-treated type 2 diabetic participants with CAD requiring PCI. 94 patients were randomized into CGM-guided or HbA1c-guided glycemic control. Serial NIRS imaging was conducted to monitor non-culprit lesions at baseline and week 48. The current sub-analysis included 78 patients with both baseline BMI data and evaluable baseline NIRS/IVUS images. Results All of study subjects received a statin (high-intensity statin use=36%), and the averaged LDL-C level was 86.7±26.3 mg/dL. The average BMI and HbA1c level were 24.7±3.1 kg/m2 and 7.5±0.9%, respectively (Table 1). On NIRS imaging analysis, maxLCBI4mm at non-culprit lesions was 286.2±167.0, and 21.8% of study subjects exhibited maxLCBI4mm >400 (Table 2). BMI was associated with maxLCBI4mm (p<0.001). Multivariate analysis adjusting clinical characteristics and LDL-C demonstrated that BMI was an independent contributor to maxLCBI4mm [estimate=17.15 (12.88-21.42), p<0.001] (Table 2). Even in patients receiving high-intensity statin, BMI was still associated with maxLCBI4mm (p<0.001). Conclusions A greater accumulation of lipidic plaque materials was observed in association with BMI in statin-treated type 2 diabetic patients with CAD. This presence of enhanced plaque vulnerability at non-culprit lesions, in the setting of obesity, may contribute to an increased risk of cardiovascular events in type 2 diabetic patients with CAD. The current finding suggests the need to adopt further therapeutic approaches to favourably modify plaque vulnerability in type 2 diabetic patients exhibiting obesity.Table 1:Clinical DemographicsTable 2:Factors Associated with maxLCBI

Plasma Somatostatin Levels Are Lower in Patients with Coronary Stenosis and Significantly Increase after Stent Implantation.

Background/Objectives: Stimulated capsaicin-sensitive peptidergic sensory nerves release somatostatin (SST), which has systemic anti-inflammatory and analgesic effects, correlating with the severity of tissue injury. Previous studies suggest that SST release into the systemic circulation is likely to serve as a protective mechanism during thoracic and orthopedic surgeries, scoliosis operations, and septic conditions, all involving significant tissue damage, pain, and inflammation. In a severe systemic inflammation rat model, SST released from sensory nerves into the bloodstream enhanced innate defense, reducing mortality. Inflammation is the key pathophysiological process responsible for the formation, progression, instability, and healing of atherosclerotic plaques. Methods: We measured SST-like immunoreactivity (SST-LI) in the plasma of healthy volunteers in different age groups and also that of stable angina patients with coronary heart disease (CHD) using ELISA and tracked changes during invasive coronary interventions (coronarography) with and without stent implantation. Samples were collected at (1) pre-intervention, (2) after coronarography, (3) 2 h after coronarography initiation and coronary stent placement, and (4) the next morning. Results: There was a strong negative correlation between SST-LI concentrations and age; the plasma SST-LI of older healthy volunteers (47-73 years) was significantly lower than in young ones (24-27 years). Baseline SST-LI in CHD patients who needed stents was significantly reduced compared to those not requiring stents. Plasma SST-LI significantly increased two hours post stent insertion and the next morning compared to pre-intervention levels. Conclusions: Age-related SST decrease might be a consequence of lower gene expression within specific hypo-thalamic nuclei as has been previously demonstrated in rodent animals. Reperfusion of ischemic myocardium post-stent implantation may trigger SST release, potentially offering protective benefits in coronary heart disease. Investigating this SST-mediated mechanism could offer valuable insights for future therapies.

Relationship between biomarkers and platelet aggregation activity in presence of hydrogen sulfide in patients with coronary heart disease

Biological significance of hydrogen sulfide (H2S) in regulation of platelet functions and in development of thrombosis is being studied, but there is no consensus on the role of H2S in these physiological processes. The platelets are very sensitive to various mediators released from blood vessels and blood cells. Multiple pro-inflammatory molecules may exert direct effects on the state of cardiovascular system. Thus, an imbalance in the production of pro-inflammatory and anti-inflammatory cytokines increases the risk of thrombosis, and it can lead to endothelial dysfunction, instability and rupture of atherosclerotic plaques. The aim of our study was to determine concentrations and identify the relationships between certain biomarkers (LIGHT, PlGF, IFNá2, TNFáâ, IL-3, IL-5, IL-6, IL-8, IL-15, IL-17F, MIP-1á, CXCL16) and collagen-induced platelet aggregation in presence of hydrogen sulfide exposure in patients with coronary heart disease. We performed a simple one-step comparative study which included 22 patients with coronary artery disease (CHD). The level of biomarkers was determined by multiplex analysis (xMAP technology). Platelet aggregation activity was studied by the turbidimetric assay. All samples were examined against the background of a 30-min pre-incubation with hydrogen sulfide, with the addition of an aggregation inducer (collagen, 2 mmol/L). Sodium hydrosulfide at a concentration of 10-6 M was used as a hydrogen sulfide donor. The results of comparative and correlation analysis were considered reliable at a statistical significance level of p 0.05. The patients were divided into two groups, i.e., group 1 (n = 10) showed a reduced aggregation or a decreased size of aggregates against the background of preincubation with H2S. In group 2 (n = 12), preincubation with H2S was followed by increased degree or size of platelet aggregates. The concentrations of tumor necrosis factor ligand (LIGHT), interferon IFNá2, interleukins IL-3, IL-8, IL-15, IL-17F, chemokine CCL3/MIP-1a were significantly increased in group 2 patients, where collagen-induced platelet aggregation increased upon preincubation H2S, as compared with patients in group 1. The correlation analysis revealed positive correlations found that in the 1st group of patients between the concentrations of MIP-1a (Rs = 0.56, p = 0.03; Rs = 0.69, p = 0.01), IL-5 (Rs = 0.83, p = 0.01; Rs = 0.73, p = 0.01), and IL-8 (Rs = 0.60, p = 0.02; Rs = 0.95, p = 0.01), respectively, and with both size of aggregates and the index of the platelet aggregation degree. Moreover, distinct correlations between the aggregate size and the concentration of IL-6 (Rs = 0.53, p = 0.04) were revealed. In the 2nd group of patients, correlations were found with the size of aggregates and PIGF (Rs = 0.59, p = 0.04), and between CXCL16 values and the size of aggregates (Rs = 0.58, p = 0.04), like as with the degree of aggregation (Rs = 0.65, p = 0.04). Thus, we have found that, in 2 groups of patients with coronary heart disease with increased collagen-induced platelet aggregation, preincubated with H2S, higher concentrations of inflammatory biomarkers (IFNá2, IL-3, IL-8, IL-15, IL-17F, MIP-1á) were detected. One may suggest that the more pronounced proinflammatory state in this group of patients may cause platelet resistance to inhibitory effect of hydrogen sulfide. In the 1st group of patients, we revealed multiple correlations of aggregation parameters with values of inflammatory markers (IL-5, IL-6, IL-8, MIP- 1a), which may be a pre-requisite for different corrective therapies for the patients of these groups.

Identification and experimental validation of KMO as a critical immune-associated mitochondrial gene in unstable atherosclerotic plaque

BackgroundThe heightened risk of cardiovascular and cerebrovascular events is associated with the increased instability of atherosclerotic plaques. However, the lack of effective diagnostic biomarkers has impeded the assessment of plaque instability currently. This study was aimed to investigate and identify hub genes associated with unstable plaques through the integration of various bioinformatics tools, providing novel insights into the detection and treatment of this condition.MethodsWeighted Gene Co-expression Network Analysis (WGCNA) combined with two machine learning methods were used to identify hub genes strongly associated with plaque instability. The cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT) method was utilized to assess immune cell infiltration patterns in atherosclerosis patients. Additionally, Gene Set Variation Analysis (GSVA) was conducted to investigate the potential biological functions, pathways, and mechanisms of hub genes associated with unstable plaques. To further validate the diagnostic efficiency and expression of the hub genes, immunohistochemistry (IHC), quantitative real-time polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA) were performed on collected human carotid plaque and blood samples. Immunofluorescence co-staining was also utilized to confirm the association between hub genes and immune cells, as well as their colocalization with mitochondria.ResultsThe CIBERSORT analysis demonstrated a significant decrease in the infiltration of CD8 T cells and an obvious increase in the infiltration of M0 macrophages in patients with atherosclerosis. Subsequently, two highly relevant modules (blue and green) strongly associated with atherosclerotic plaque instability were identified. Through intersection with mitochondria-related genes, 50 crucial genes were identified. Further analysis employing least absolute shrinkage and selection operator (LASSO) logistic regression and support vector machine recursive feature elimination (SVM-RFE) algorithms revealed six hub genes significantly associated with plaque instability. Among them, NT5DC3, ACADL, SLC25A4, ALDH1B1, and MAOB exhibited positive correlations with CD8 T cells and negative correlations with M0 macrophages, while kynurenine 3-monooxygenas (KMO) demonstrated a positive correlation with M0 macrophages and a negative correlation with CD8 T cells. IHC and RT-qPCR analyses of human carotid plaque samples, as well as ELISA analyses of blood samples, revealed significant upregulation of KMO and MAOB expression, along with decreased ALDH1B1 expression, in both stable and unstable samples compared to the control samples. However, among the three key genes mentioned above, only KMO showed a significant increase in expression in unstable plaque samples compared to stable plaque samples. Furthermore, the expression patterns of KMO in human carotid unstable plaque tissues and cultured mouse macrophage cell lines were assessed using immunofluorescence co-staining techniques. Finally, lentivirus-mediated KMO silencing was successfully transduced into the aortas of high-fat-fed ApoE-/- mice, with results indicating that KMO silencing attenuated plaque formation and promoted plaque stability in ApoE-/- mice.ConclusionsThe results suggest that KMO, a mitochondria-targeted gene associated with macrophage cells, holds promise as a valuable diagnostic biomarker for assessing the instability of atherosclerotic plaques.

OxLDL as a prognostic biomarker of plaque instability in patients qualified for carotid endarterectomy.

Atherosclerotic plaque instability increases the risk of stroke. As such, determining the nature of an instability atherosclerotic plaque may speed up qualification for carotid endarterectomy (CEA), thus reducing the risk of acute vascular events. The aim of the study was to determine the diagnostic value of oxidized LDL cholesterol (ox-LDL), matrix metalloproteinase 9 (MMP-9) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in serum as a prognostic markers of instability atherosclerotic plaques. Serum was collected from 67 patients who underwent CEA in accordance with the qualification criteria. The levels of ox-LDL, MMP-9 and 8-OHdG were assessed by ELISA. The predictive value of the markers was determined based on an ROC curve, and the cut-off points with the highest sensitivity and specificity were determined. Patients with unstable atherosclerotic plaque had significantly higher serum ox-LDL, MMP-9 and 8-OHdG values. It was found that in patients before CEA, ox-LDL >31.4 ng/mL was associated with an 82.5% probability of unstable atherosclerotic plaque, MMP-9 >113.1 ng/mL with 78.6%, and 8-OHdG >2.15 ng/mL with 64.7%. Multivariate regression analysis found ox-LDL to be an independent factor associated with plaque instability. Patients with unstable plaques tend to have higher serum levels of ox-LDL, MMP-9 and 8-OHdG compared to those with stable plaques. The optimal cut-off point for ox-LDL (AUC 0.86, p <0.0001) was 31.14 ng/mL, with 91.18% sensitivity and 78.79% specificity. The high sensitivity and specificity of ox-LDL suggests that it can be used as an independent marker of plaque instability.

Notoginsenoside R1 decreases intraplaque neovascularization by governing pericyte-endothelial cell communication via Ang1/Tie2 axis in atherosclerosis.

Atherosclerosis represents the major cause of mortality worldwide and triggers higher risk of acute cardiovascular events. Pericytes-endothelial cells (ECs) communication is orchestrated by ligand-receptor interaction generating a microenvironment which results in intraplaque neovascularization, that is closely associated with atherosclerotic plaque instability. Notoginsenoside R1 (R1) exhibits anti-atherosclerotic bioactivity, but its effect on angiogenesis in atherosclerotic plaque remains elusive. The aim of our study is to explore the therapeutic effect of R1 on vulnerable plaque and investigate its potential mechanism against intraplaque neovascularization. The impacts of R1 on plaque stability and intraplaque neovascularization were assessed in ApoE-/- mice induced by high-fat diet. Pericytes-ECs direct or non-direct contact co-cultured with VEGF-A stimulation were used as the in vitro angiogenesis models. Overexpressing Ang1 in pericytes was performed to investigate the underlying mechanism. In vivo experiments, R1 treatment reversed atherosclerotic plaque vulnerability and decreased the presence of neovessels in ApoE-/- mice. Additionally, R1 reduced the expression of Ang1 in pericytes. In vitro experiments demonstrated that R1 suppressed pro-angiogenic behavior of ECs induced by pericytes cultured with VEGF-A. Mechanistic studies revealed that the anti-angiogenic effect of R1 was dependent on the inhibition of Ang1 and Tie2 expression, as the effects were partially reversed after Ang1 overexpressing in pericytes. Our study demonstrated that R1 treatment inhibited intraplaque neovascularization by governing pericyte-EC association via suppressing Ang1-Tie2/PI3K-AKT paracrine signaling pathway. R1 represents a novel therapeutic strategy for atherosclerotic vulnerable plaques in clinical application.

Influence of Dulaglutide on Serum Biomarkers of Atherosclerotic Plaque Instability: An Interventional Analysis of Cytokine Profiles in Diabetic Subjects-A Pilot Study.

Background and Objectives: The rise in global diabetes cases, reaching a staggering 529 million in 2021 from 108 million in 1980, underscores the urgency of addressing its complications, notably macrovascular ones like coronary artery, cerebrovascular, and peripheral artery diseases, which contribute to over 50% of diabetes mortality. Atherosclerosis, linked to hyperglycemia-induced endothelial dysfunction, is pivotal in cardiovascular disease development. Cytokines, including pentraxin 3 (PTX3), copeptin, lipoprotein(a) [Lp(a)], and matrix metalloproteinase-9 (MMP-9), influence atherosclerosis progression and plaque vulnerability. Inhibiting atherosclerosis progression is crucial, especially in diabetic individuals. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs), increasingly used for type 2 diabetes, show promise in reducing the cardiovascular risk, sparking interest in their effects on atherogenesis. This study sought to examine the effects of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) on biomarkers that indicate the instability of atherosclerotic plaques. These biomarkers include pentraxin 3 (PTX3), copeptin (CPC), matrix metalloproteinase-9 (MMP-9), and lipoprotein(a) [Lp(a)]. Materials and Methods: A total of 34 participants, ranging in age from 41 to 81 years (with an average age of 61), who had been diagnosed with type 2 diabetes mellitus (with a median HbA1c level of 8.8%), dyslipidemia, and verified atherosclerosis using B-mode ultrasonography, were included in the study. All subjects were eligible to initiate treatment with a GLP-1 RA-dulaglutide. Results: Significant reductions in anthropometric parameters, blood pressure, fasting glucose levels, and HbA1c levels were observed posttreatment. Moreover, a notable decrease in biochemical markers associated with atherosclerotic plaque instability, particularly PTX3 and MMP-9 (p < 0.001), as well as Lp(a) (p < 0.05), was evident following the GLP-1 RA intervention. Conclusions: These findings underscore the potential of GLP-1 RAs in mitigating atherosclerosis progression and plaque vulnerability, thus enhancing cardiovascular outcomes in individuals with type 2 diabetes mellitus.

The suppression of FSP1 expression via NRF2 promotes ferroptosis induced by reactive oxygen species in vascular smooth muscle cells

Death of vascular smooth muscle cells (VSMC) induced by reactive oxygen species (ROS) may occur as ferroptosis, contributing to atherosclerotic plaque instability and rupture. Although it is involved in ROS-induced VSMC death, the role of nuclear transcription factors erythroid 2 related factor 2 (NRF2) in ferroptosis remains unclear. This study was designed to determine the coupling between NRF2 and antioxidant ferroptosis suppressor protein 1 (FSP1) in ROS-induced VSMC ferroptosis. We exposed mouse aortic VSMCs to hydrogen peroxide (H2O2), and cell death was characterized by increased NRF2 expression and inhibition of FSP1 expression. The results demonstrated that VSMC exposure to H2O2 emerged as the characteristic of ferroptosis·H2O2 promoted the expression and nuclear translocation of NRF2 and downregulated FSP1 expression. These data imply a novel and important role for NRF2/FSP1 in ferroptosis for treating VSMCs ferroptosis-associated diseases.

Single-nucleus transcriptomics of epicardial adipose tissue from female pigs reveals effects of exercise training on resident innate and adaptive immune cells

BackgroundCoronary artery disease (CAD) is a leading cause of death in women. Epicardial adipose tissue (EAT) secretes cytokines to modulate coronary artery function, and the release of fatty acids from EAT serves as a readily available energy source for cardiomyocytes. However, despite having beneficial functions, excessive amounts of EAT can cause the secretion of proinflammatory molecules that increase the instability of atherosclerotic plaques and contribute to CAD progression. Although exercise mitigates CAD, the mechanisms by which exercise impacts EAT are unknown. The Yucatan pig is an excellent translational model for the effects of exercise on cardiac function. Therefore, we sought to determine if chronic aerobic exercise promotes an anti-inflammatory microenvironment in EAT from female Yucatan pigs.MethodsSexually mature, female Yucatan pigs (n = 7 total) were assigned to sedentary (Sed, n = 3) or exercise (Ex, n = 4) treatments, and coronary arteries were occluded (O) with an ameroid to mimic CAD or remained non-occluded (N). EAT was collected for bulk (n = 7 total) and single nucleus transcriptomic sequencing (n = 2 total, 1 per exercise treatment).ResultsBased on the bulk transcriptomic analysis, exercise upregulated S100 family, G-protein coupled receptor, and CREB signaling in neurons canonical pathways in EAT. The top networks in EAT affected by exercise as measured by bulk RNA sequencing were SRC kinase family, fibroblast growth factor receptor, Jak-Stat, and vascular endothelial growth factor. Single nucleus transcriptomic analysis revealed that exercise increased the interaction between immune, endothelial, and mesenchymal cells in the insulin-like growth factor pathway and between endothelial and other cell types in the platelet endothelial cell adhesion molecule 1 pathway. Sub-clustering revealed nine cell types in EAT, with fibroblast and macrophage populations predominant in O-Ex EAT and T cell populations predominant in N-Ex EAT. Unlike the findings for exercise alone as a treatment, there were not increased interactions between endothelial and mesenchymal cells in O-Ex EAT. Coronary artery occlusion impacted the most genes in T cells and endothelial cells. Genes related to fatty acid metabolism were the most highly upregulated in non-immune cells from O-Ex EAT. Sub-clustering of endothelial cells revealed that N-Ex EAT separated from other treatments.ConclusionsAccording to bulk transcriptomics, exercise upregulated pathways and networks related to growth factors and immune cell communication. Based on single nucleus transcriptomics, aerobic exercise increased cell-to-cell interaction amongst immune, mesenchymal, and endothelial cells in female EAT. Yet, exercise was minimally effective at reversing alterations in gene expression in endothelial and mesenchymal cells in EAT surrounding occluded arteries. These findings lay the foundation for future work focused on the impact of exercise on cell types in EAT.

The Role of Neutrophils, Lymphocytes and Monocytes in Ischemic Heart Disease: Friend or Foe?

Ischemic heart disease (IHD) remains a leading cause of morbidity and mortality globally. In recent years research has increasingly focused on the interplay between the white blood cells and the development and progression of IHD. Neutrophils, lymphocytes, and Monocytes play an important role in the immune system and were found to have dual roles in both protective mechanisms and harmful effects. Neutrophils are traditionally viewed as first responders to tissue injury. Their rapid infiltration aids in the clearance of cellular debris and pathogens, while the release of reactive oxygen species and inflammatory mediators can exacerbate tissue damage. Additionally, neutrophils participate in intercommunication with endothelial cells and platelets, influencing the progression of atherosclerosis and thrombosis. Lymphocytes, a key player in adaptive immune response, similarly exhibit a dual role in IHD. Their involvement extends beyond immune surveillance. Monocytes contribute to phagocytosis and tissue repair while some of their actions cause atherosclerotic plaque instability. This review provides an overview of IHD, covering its prevalence, pathogenesis, risk factors, clinical manifestations, diagnosis, and the involvement of white blood cells, including neutrophils, lymphocytes, and monocytes, in the disease process.

Relationship between fibroblast growth factor in plasma and carotid plaque neovascularization: a pilot study.

Unstable atherosclerotic carotid plaques with intraplaque neovascularization (IPN) carry a substantial risk for ischemic stroke. Conventional ultrasound methods fall short in detecting IPN, where superb microvascular imaging (SMI) has emerged as a promising tool for both visualizing and quantification. High levels of fibroblast growth factor 23 (FGF-23) have, in observational studies, been suggested as related to cardiovascular morbidity and mortality. The association of FGF-23 to atherosclerotic carotid plaque instability remains relatively unexplored. A cohort of twenty-nine patients with ≥50% atherosclerotic carotid stenosis underwent conventional carotid ultrasound, SMI, and blood tests, including measurement of FGF-23 in plasma. Nineteen patients were characterized as symptomatic and ten as asymptomatic. Our major findings were: i) Higher FGF-23 levels were strongly correlated with increased SMI-assessed IPN. ii) Neo-vessel count recorded by quantitative SMI was positively correlated to increased FGF-23 levels, but not with basic FGF levels. (iii) In contrast, traditional risk factors for plaque instability exhibited no noteworthy associations with SMI-assessed IPN or with FGF-23 levels. This pilot study suggest the potential of FGF-23 as a valuable marker for neovascularization and atherosclerotic carotid plaque instability as a risk factor for ischemic stroke. Further research involving larger cohorts and prospective data is necessary to understand FGF-23's role in this context comprehensively.

CXCL1 as a Potential Biomarker of Plaque Instability in Carotid Stenosis. Preliminary Report.

Biomarkers of atherosclerotic plaque instability are needed. This study aimed to evaluate the level of chemokine CXCL1 (CXC motif ligand 1) in plasma and atherosclerotic plaques in patients with carotid stenosis and correlate that with plaque morphology. The study group included 82 patients (30 women and 52 men) aged 50-90 years (mean 68.1 ± 8.9) who underwent elective carotid endarterectomy. The obtained atherosclerotic plaques were macroscopically and microscopically assessed according to the American Heart Association (AHA) classification. Fifty-one (62.2%) and 31 (37.8%) of the plaques were unstable and stable, respectively. The mean concertation of CXCL1 in plaques in asymptomatic and symptomatic patients was 0.00 (±0.00) vs 88.90 (±95.19) pg/ml, respectively (P = 0.000). The mean plasma concentration of CXCL1 in the study group was 42.40 (±85.79) pg/ml, while in the control group (healthy volunteers without lesions in the carotid arteries) it was 0.00 pg/mL (±0.00) (P = 0.000). The mean plasma CXCL1 concertation in asymptomatic and symptomatic patients was 22.08 (±49.13) versus 67.72 (±107.91) pg/ml, respectively (P = 0.031). Significantly higher CXCL1 concentration in atherosclerotic plaques and plasma in symptomatic patients compared with asymptomatic patients probably resulted from unstable lesions in the carotid arteries.

Blockade of endothelial adenosine receptor 2 A suppresses atherosclerosis in vivo through inhibiting CREB-ALK5-mediated endothelial to mesenchymal transition

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and morbidity and mortality rates continue to rise. Atherosclerosis constitutes the principal etiology of CVDs. Endothelial injury, inflammation, and dysfunction are the initiating factors of atherosclerosis. Recently, we reported that endothelial adenosine receptor 2 A (ADORA2A), a G protein-coupled receptor (GPCR), plays critical roles in neovascularization disease and cerebrovascular disease. However, the precise role of endothelial ADORA2A in atherosclerosis is still not fully understood. Here, we showed that ADORA2A expression was markedly increased in the aortic endothelium of humans with atherosclerosis or Apoe-/- mice fed a high-cholesterol diet. In vivo studies unraveled that endothelial-specific Adora2a deficiency alleviated endothelial-to-mesenchymal transition (EndMT) and prevented the formation and instability of atherosclerotic plaque in Apoe-/- mice. Moreover, pharmacologic inhibition of ADORA2A with KW6002 recapitulated the anti-atherogenic phenotypes observed in genetically Adora2a-deficient mice. In cultured human aortic endothelial cells (HAECs), siRNA knockdown of ADORA2A or KW6002 inhibition of ADORA2A decreased EndMT, whereas adenoviral overexpression of ADORA2A induced EndMT. Mechanistically, ADORA2A upregulated ALK5 expression via a cAMP/PKA/CREB axis, leading to TGFβ-Smad2/3 signaling activation, thereby promoting EndMT. In conclusion, these findings, for the first time, demonstrate that blockade of ADORA2A attenuated atherosclerosis via inhibition of EndMT induced by the CREB1-ALK5 axis. This study discloses a new link between endothelial ADORA2A and EndMT and indicates that inhibiting endothelial ADORA2A could be an effective novel strategy for the prevention and treatment of atherosclerotic CVDs.

What Is the Added Value of Carotid CEUS in the Characterization of Atherosclerotic Plaque?

Background and Objectives: Unstable atherosclerotic plaque in the arteries is one of the main risk factors for cerebral ischemia. Duplex ultrasound is a frequently used diagnostic method, but it has some limitations for microvascularization and neovascularization evaluation. The aim of this review was to evaluate the role of the new multiparametric US method-contrast-enhanced ultrasound (CEUS)-in atherosclerotic plaque instability verification. Materials and Methods: Original studies, reviews, and meta-analyses were included in this article. A total of 53 studies were retrieved; 29 were included in this study. Results: Carotid artery CEUS as a part of the multiparametric ultrasound method shows promising results and provides additional characteristics of soft- and high-risk atherosclerotic plaques; it can be advised in clinical practice for patients with carotid artery soft- and high-risk plaques. However, there are some limitations, such as extensive calcinosis with important acoustic shadows in carotid atherosclerotic plaque neovascularization diagnostics by CEUS. The added value of CEUS in the characterization of atherosclerotic plaque is that it indicates regions with high neovascularization and visualizes ulcerations on plaque surfaces, suggestive of increased instability risk.

Mechanisms of Atherosclerotic Plaque Instability

Cardiovascular disease (CVD) is the leading cause of mortality in humans worldwide. The main cause of CVD is the formation of thrombi due to by unstable atherosclerotic plaque rupture on the arterial wall. Long-term accumulation of thrombi results in vascular remodeling, and subsequent-stenosis of the lumen obstructs the blood flow, thereby leading to myocardial tissue ischemia and hypoxia. Sustained ischemia and hypoxia lead to myocyte necrosis, resulting in irreversible myocardial injury. Many molecular and cellular mechanisms are associated with atherosclerotic plaque instability (API). For example, macrophages can produce various inflammatory factors, adhesion factors, chemokines and matrix metalloproteinases (MMPs), which play important roles in the pathophysiological mechanisms of API and in maintaining plaque stability. These molecules may help predict unstable atherosclerotic plaques. If the plaque is stable, it will not be prone to rupture or thrombosis. Accordingly, in this review, we will discuss the different pathophysiological mechanisms of API and the related roles of macrophages in the mechanisms of API mainly in animal models and humans. We believe this review will provide a theoretical basis for the development of treatments and diagnostic approaches for the management of API.

Identification of a hub gene VCL for atherosclerotic plaques and discovery of potential therapeutic targets by molecular docking

BackgroundAtherosclerosis (AS) is a pathology factor for cardiovascular diseases and instability of atherosclerotic plaques contributes to acute coronary events. This study identified a hub gene VCL for atherosclerotic plaques and discovered its potential therapeutic targets for atherosclerotic plaques.MethodsDifferential expressed genes (DEGs) were screened between unstable and stable plaques from GSE120521 dataset and then used for construction of a protein-protein interactions (PPI) network. Through topological analysis, hub genes were identified within this PPI network, followed by construction of a diagnostic model. GSE41571 dataset was utilized to validate the diagnostic model. A key hub gene was identified and its association with immune characteristics and pathways were further investigated. Molecular docking and molecular dynamics (MD) simulation were employed to discover potential therapeutic targets.ResultsAccording to the PPI network, 3 tightly connected protein clusters were found. Topological analysis identified the top 5 hub genes, Vinculin (VCL), Dystrophin (DMD), Actin alpha 2 (ACTA2), Filamin A (FLNA), and transgelin (TAGLN). Among these hub genes, VCL had the highest diagnostic value. VCL was selected for further analysis and we found that VCL was negatively correlated with immune score and AS-related inflammatory pathways. Next, we identified 408 genes that were highly correlated with VCL and determined potential drug candidates. The results from molecular docking and MD simulation showed compound DB07117 combined with VCL protein stably, the binding energy is -7.7 kcal/mol, indicating that compound DB07117 was a potential inhibitor of VCL protein.ConclusionThis study identified VCL as a key gene for atherosclerotic plaques and provides a potential therapeutic target of VCL for the treatment of atherosclerotic plaques.

Arsenic trioxide alleviates atherosclerosis by inhibiting CD36-induced endocytosis and TLR4/NF-κB-induced inflammation in macrophage and ApoE-/- mice

BackgroundInflammation and lipid accumulation are key events in atherosclerosis progression. Despite arsenic trioxide’s (ATO) toxicity, at appropriate doses, it is a useful treatment for various diseases treatment. ATO prevents vascular restenosis; however, its effects on atherosclerotic plaque development and instability remain unclear. MethodsApoE-/- mice were fed high-fat diet for 4 months, and starting at the third month, ATO was intravenously administered every other day. Atherosclerotic lesion size, histological characteristics, and related protein and lipid profiles were assessed using samples from the aorta, carotid artery, and serum. The anti-inflammatory and anti-pyroptosis effects of ATO were investigated by stimulating RAW264.7 and THP-1 cell lines with oxidized low-density lipoprotein (ox-LDL) or lipopolysaccharide (LPS). ResultsATO reduced atherosclerotic lesion formation and plasma lipid levels in ApoE-/- mice. In the serum and aortic plaques, ATO reduced the levels of pro-inflammatory factors, including interleukin (IL) 6 and tumor necrosis factor α, but increased IL-10 levels. Mechanistically, ATO promoted the CD36-mediated internalization of ox-LDL in a peroxisome proliferator-activated receptor γ-dependent manner. Furthermore, ATO downregulated Toll-like receptor 4 (TLR4) expression in plaques and macrophages and inhibited p65 nuclear translocation and IκBα degradation. ATO reduced macrophage pyroptosis by downregulating NLR family pyrin domain-containing 3 (NLRP3) expression and caspase 1 activation. ConclusionATO has potential atheroprotective effects, especially in macrophages. The mechanisms were inhibition of CD36-mediated foam cell formation and suppression of inflammatory responses and pyroptosis mediated by TLR4/nuclear factor κB and NLRP3 activation. Our findings provide evidence supporting the potential atheroprotective value of ATO.

Активность теломеразы, гиперлипидемия и особенности атеросклеротического поражения брахиоцефальных артерий у бессимптомных пациентов трудоспособного возраста с субклиническим гипотиреозом

Aim. To study telomerase activity, lipidemia and to assess the severity of atherosclerotic lesions of the brachiocephalic arteries in asymptomatic patients of working age with subclinical hypothyroidism. Design. A cross-sectional cohort study. Materials and methods. Data on 131 patients of working age (32 men and 99 women) with different hormonal status of the thyroid gland (thyroid) without clinical signs of chronic cerebral circulatory insufficiency were analyzed. Based on the assessment of the hormonal status of the thyroid gland, 2 groups of patients were formed: 87 with laboratory-confirmed hypertension (thyroid-stimulating hormone level &gt; 4.0 mMU/l with normal characteristics of free fractions of thyroid hormones) and 44 patients without thyroid dysfunction. The groups formed were comparable in age, gender composition, presence and severity of hypertension, aggravated family history of early cardiovascular events, and smoking. All patients underwent ultrasound examination of the brachiocephalic arteries, determination of the lipid spectrum and telomerase concentration. The processing of the obtained data was carried out using statistical packages Excel, Statistica v. 10.0. The data obtained were interpreted as reliable, and the differences between the indicators were considered significant when the error-free prediction value was equal to or greater than 95% (p &lt; 0.05). Results. In the group of people with hypothyroidism, the proportion of people with multivessel atherosclerotic lesion was higher (34.5% (n = 30) vs. 13.6% (n = 6) (χ2 = 6.37; p &lt; 0.05)), one or a combination of several signs of instability of atherosclerotic plaque (41.4% (n = 36) vs. 18.2% (n = 8) (χ2 = 7.05; p &lt; 0.01)). In patients with subclinical hypothyroidism, precerebral atherosclerosis occurs against the background of atherogenic type IIa secondary hyperlipidemia (67.8% (n = 59) vs. 34.1% (n = 6) (χ2 = 13.52; p &lt; 0.001) in combination with insufficiency of antiatherogenic high density lipoproteins (74.7% (n = 65) vs. 45.5% (n = 20) (χ2 = 10.98; p &lt; 0.001)), lower values of telomerase concentration in comparison with the group of people without thyroid dysfunction: (8.2 (7.4–9.5) vs. 10.8 (10.1–12.2) ng/ml (p &lt; 0.001)). The relationship between the level of telomerase activity (r = –0.72; p &lt; 0.05) and the presence of subclinical hypothyroidism, atherosclerotic lesions of the precerebral bed in patients (r = –0.33; p &lt; 0.05) was established. Conclusion. In clinically healthy patients of working age with newly diagnosed, medically uncorrected subclinical hypothyroidism, the proportion of persons with ultrasound signs of multivessel atherosclerotic lesions of the brachiocephalic arteries is higher, and precerebral atherosclerosis occurs against the background of atherogenic type IIa secondary hyperlipidemia in combination with insufficiency of antiatherogenic high density lipoproteins, lower values of telomerase activity in comparison with the group of persons without thyroid dysfunction. Etiopathogenetic mechanisms of "early vascular aging", the criteria for stratification of risk groups for atherosclerosis-associated cardiovascular disease, the choice of diagnostic algorithms for visualizing preclinical stages of atherogenesis, and timely antiatherogenic tactics in asymptomatic patients with comorbid thyroid pathology require further study. Verification of a stenosing hemodynamically significant or non-hemodynamically significant atherosclerotic lesion of the coronary basin, regardless of the clinical component, is a factor of high cardiovascular risk requiring immediate correction of hyperlipidemia. Keywords: thyroid gland, hypothyroidism, hyperlipidemia, atherosclerosis, precerebral (brachiocephalic) arteries, telomerase activity, comorbid pathology.