New insight into biology, molecular diagnostics and treatment options of unstable carotid atherosclerotic plaque: a narrative review

High-resolution magnetic resonance imaging features of time-of-flight magnetic resonance angiography signal loss and its relevance to ischemic stroke

Background

Focal signal loss of intracranial artery stenosis is commonly observed on three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA). We aimed to investigate the underlying pathophysiology of vessel signal loss observed on 3D-TOF-MRA and its relevance to recent ischemic stroke.

Methods

High-resolution magnetic resonance imaging (HR-MRI) was performed in 401 patients with unilateral or bilateral moderate-to-severe stenosis (50-99%) of the middle cerebral artery (MCA) on TOF-MRA. The patients were classified according to the presence or absence of focal signal loss in the M1 segment of the MCA. The wall features between the vessels with and without signal loss were compared, and their relationship with recent ischemic stroke was analyzed.

Results

A total of 414 stenotic lesions caused by atherosclerotic plaque were detected, including 231 with signal loss on TOF-MRA and 183 without. The signal loss group, compared to the group without signal loss, showed a higher degree of stenosis (P<0.001), grade 2 enhanced plaques (82.3% vs. 28.4%; P<0.001), and concentric pattern (63.2% vs. 34.4%; P<0.001). Multivariate analysis suggested grade 2 enhanced plaques and concentric pattern were independently associated with signal loss. Patients in the signal loss group were more likely to have had a recent ischemic stroke (62.4% vs. 40.4%; P<0.001).

Conclusions

In addition to the degree of stenosis, the vulnerability and morphology of plaques on HR-MRI may influence signals on 3D-TOF-MRA. The presence of signal loss on 3D-TOF-MRA is associated with recent ischemic stroke.

Gray-Scale Median in Patients with Symptomatic and Asymptomatic Carotid Atherosclerosis-Risk Factors and Diagnostic Potential

BACKGROUND

The identification of clinical factors affecting the gray-scale median (GSM) and determination of GSM diagnostic utility for differentiating between symptomatic and asymptomatic internal carotid artery (ICA) stenosis.

METHODS

This study included 45 patients with asymptomatic and 40 patients with symptomatic ICA stenosis undergoing carotid endarterectomy (CEA). Echolucency of carotid plaque was determined using computerized techniques for the GSM analysis. Study groups were compared in terms of clinical risk factors, coexisting comorbidities, and used pharmacotherapy.

RESULTS

Mean GSM values in the symptomatic group were significantly lower than in the asymptomatic group (p < 0.001). Both in the univariate as well as in the multiple regression analysis, GSM was significantly correlated with D-dimers and fasting plasma glucose levels and tended to correlate with β-adrenoceptor antagonist use in the symptomatic group. In asymptomatic patients, GSM was associated with the presence of grade 2 and grade 3 hypertension, and tended to correlate with the use of metformin, sulfonylureas, and statin. Independent factors for GSM in this group remained as grade 3 hypertension and statin's therapy. The receiver operating characteristic (ROC) analysis revealed that GSM differentiated symptomatic from asymptomatic ICA stenosis with sensitivity and specificity of 73% and 80%, respectively.

CONCLUSION

The completely diverse clinical parameters may affect GSM in symptomatic and asymptomatic patients undergoing CEA, whose clinical characteristics were similar in terms of most of the compared parameters. GSM may be a clinically useful parameter for differentiating between symptomatic and asymptomatic ICA stenosis.

Inflammatory Biomarkers to Predict Major Adverse Cardiovascular Events in Patients with Carotid Artery Stenosis

Background and Objectives: Inflammatory proteins and their prognostic value in patients with carotid artery stenosis (CAS) have not been adequately studied. Herein, we identified CAS-specific biomarkers from a large pool of inflammatory proteins and assessed the ability of these biomarkers to predict adverse events in individuals with CAS. Materials and Methods: Samples of blood were prospectively obtained from 336 individuals (290 with CAS and 46 without CAS). Plasma concentrations of 29 inflammatory proteins were determined at recruitment, and the patients were followed for 24 months. The outcome of interest was a major adverse cardiovascular event (MACE; composite of stroke, myocardial infarction, or death). The differences in plasma protein concentrations between patients with vs. without a 2-year MACE were determined using the independent t-test or Mann-Whitney U test to identify CAS-specific prognostic biomarkers. Kaplan-Meier and Cox proportional hazards analyses with adjustment for baseline demographic and clinical characteristics were performed to assess the prognostic value of differentially expressed inflammatory proteins in predicting a 2-year MACE in patients with CAS. Results: The mean age of the cohort was 68.8 (SD 10.2) years and 39% were female. The plasma concentrations of two inflammatory proteins were significantly higher in individuals with a 2-year MACE relative to those without a 2-year MACE: IL-6 (5.07 (SD 4.66) vs. 3.36 (SD 4.04) pg/mL, p = 0.03) and CD163 (233.825 (SD 230.306) vs. 159.673 (SD 175.669) pg/mL, p = 0.033). Over a follow-up period of 2 years, individuals with elevated levels of IL-6 were more likely to develop MACE (HR 1.269 (95% CI 1.122-1.639), p = 0.042). Similarly, over a 2-year period, patients with high levels of CD163 were more likely to develop MACE (HR 1.413 (95% CI 1.022-1.954), p = 0.036). Conclusions: The plasma levels of inflammatory proteins IL-6 and CD163 are independently associated with adverse outcomes in individuals with CAS. These CAS-specific prognostic biomarkers may assist in the risk stratification of patients at an elevated risk of a MACE and subsequently guide further vascular evaluation, specialist referrals, and aggressive medical/surgical management, thereby improving outcomes for patients with CAS.

Remnant cholesterol is associated with unstable carotid plaque in a neurologically healthy population

BACKGROUND

Remnant cholesterol (RC) is considered to be one of the most significant and important risk factors for atherosclerotic cardiovascular disease (ASCVD). Nonetheless, the association between RC and unstable carotid plaque remains unclear. Our primary objective is to ascertain whether RC exhibits an independent and significant association with unstable carotid plaque in a neurologically healthy population.

METHODS

In the cross-sectional study, we enrolled neurologically healthy participants who visited our centre for health checkups between 2021 and 2022. All eligible participants underwent a standardised questionnaire, physical examinations and laboratory testing. The carotid plaque was evaluated with a standard carotid ultrasound and an advanced ultrasound imaging technique called superb microvascular imaging. The correlation between lipids and unstable carotid plaque was primarily assessed utilising univariate and multivariate logistic regression.

RESULTS

The study totally enrolled 1100 participants who had an average age of 57.00 years (IQR: 49.00-63.00), with 67.55% being men. Among the participants, 321 (29.18%) had unstable carotid plaque. In the multivariate logistic regression analysis, higher RC had an independent association with an elevated incidence of unstable carotid plaque compared with the lowest concentrations of RC (OR=1.673, 95% CI 1.113 to 2.515, p=0.0134), but not other lipids. In addition, apolipoprotein A1 was negatively related to unstable carotid plaque (OR=0.549, 95% CI 0.364 to 0.830, p=0.0045).

CONCLUSIONS

Elevated concentrations of RC are independently and excellently correlated with unstable carotid plaque within a neurologically healthy population.

Inflammation in diabetes complications: molecular mechanisms and therapeutic interventions

At present, diabetes mellitus (DM) has been one of the most endangering healthy diseases. Current therapies contain controlling high blood sugar, reducing risk factors like obesity, hypertension, and so on; however, DM patients inevitably and eventually progress into different types of diabetes complications, resulting in poor quality of life. Unfortunately, the clear etiology and pathogenesis of diabetes complications have not been elucidated owing to intricate whole-body systems. The immune system was responsible to regulate homeostasis by triggering or resolving inflammatory response, indicating it may be necessary to diabetes complications. In fact, previous studies have been shown inflammation plays multifunctional roles in the pathogenesis of diabetes complications and is attracting attention to be the meaningful therapeutic strategy. To this end, this review systematically concluded the current studies over the relationships of susceptible diabetes complications (e.g., diabetic cardiomyopathy, diabetic retinopathy, diabetic peripheral neuropathy, and diabetic nephropathy) and inflammation, ranging from immune cell response, cytokines interaction to pathomechanism of organ injury. Besides, we also summarized various therapeutic strategies to improve diabetes complications by target inflammation from special remedies to conventional lifestyle changes. This review will offer a panoramic insight into the mechanisms of diabetes complications from an inflammatory perspective and also discuss contemporary clinical interventions.

Network Proteins of Human Sortilin1, Its Expression and Targetability Using Lycopene

BACKGROUND

Sortilin1 (SORT1) is a ubiquitously expressed transporter involved in sorting or clearing proteins and is pathologically linked to tissue fibrosis and calcification. Targeting SORT1 may have potential clinical efficacy in controlling or reversing cardiovascular fibrosis and/or calcification. Hence, this study assessed the protein-protein network of human SORT1 and its targetability using known nutra-/pharmaceuticals.

MATERIAL AND METHODS

Network proteins of human SORT1 were identified using the String database, and the affinity of the protein-protein interaction of this network was analysed using Chimera software (Chimera-1.17.3-mac64). The tissue-specific expression profile of SORT1 was evaluated and assessed for enrichment in different cell types, including immune cells. A library of in-house small molecules and currently used therapeutics for cardiovascular diseases were screened using AutoDock Vina to assess the targetability of human SORT1. The concentration affinity (CA) ratio of the small molecules was estimated to assess the clinical feasibility of targeting SORT1.

RESULTS

IGF2R, NTRK2, GRN and GGA1 were identified as high-affinity interaction networks of SORT1. Of these high-affinity interactions, IGF2R and GRN can be considered relevant networks in regulating tissue fibrosis or the microcalcification process due to their influence on T-cell activation, inflammation, wound repair, and the tissue remodelling process. The tissue cell-type enrichment indicated major expression of SORT1 in adipocytes, specialised epithelial cells, monocytes, cardiomyocytes, and thyroid glandular cells. The binding pocket analysis of human SORT1 showed twelve potential drug interaction sites with varying binding scores (0.86 to 5.83) and probability of interaction (0.004 to 0.304). Five of the drug interaction sites were observed to be targetable at the therapeutically feasible concentration of the small molecules evaluated. Empagliflozin, sitagliptin and lycopene showed a superior affinity and CA ratio compared to established inhibitors of SORT1.

CONCLUSION

IGF2R and GRN are relevant networks of SORT1, regulating tissue fibrosis or the microcalcification process. SORT1 can be targeted using currently approved small-molecule therapeutics (empagliflozin and sitagliptin) or widely used nutraceuticals (lycopene), which should be evaluated in a randomised clinical trial to assess their efficacy in reducing the cardiac/vascular microcalcification process.

Subclinical atherosclerosis in Behcet's disease and its inverse relation to azathioprine use: an updated meta-analysis

To evaluate the intima media thickness of carotid arteries (IMT) and its clinical, laboratory and treatment correlates in Behcet's disease (BD). Systematic search of EMBASE and PubMed databases from January 2016 to October 2022; we employed random effect meta-analyses for continuous outcomes and Peto's odds ratio for rare events. The meta-analysis included 36 case control studies: the IMT was greater in BD (n = 1103) than in controls (n = 832) (p < 0.0001) with wide heterogeneity (I2 = 86.9%); a sensitivity analysis that included mean age of BD participants, gender, disease duration and activity, atherogenic index of plasma, blood pressure, C-reactive protein, ethnicity, smoking status, anti-inflammatory and immune suppressive agents, revealed that male gender, mean age of participants and azathioprine use (the latter two in inverse fashion) partly explained the heterogeneity variance (p = 0.02, p = 0.005, and p = 0.01). The IMT was greater in vascular (n = 114) than in non-vascular BD (n = 214) (p = 0.006). BD patients (n = 782) had a greater pooled prevalence of carotid plaques than controls (n = 537) (13.1% vs. 2.97%, p < 0.0001). Subclinical carotid artery atherosclerosis represents a vascular feature of BD, independently of the traditional cardiovascular risk factors. The inverse correlations between IMT, age and azathioprine use suggest that thicker carotid arteries at disease onset eventually regress with immune suppressive treatment: this assumption needs verification on adequately designed clinical trials.

Aortic propagation velocity in predicting coronary artery disease: A systematic review and meta-analysis

INTRODUCTION

Coronary artery disease (CAD) and its outcome, myocardial infarction, is yet a significant etiology of mortality and morbidity nowadays. The aortic propagation velocity (APV) can be a simple, straightforward and novel echocardiographic index for the risk stratification in the evaluation of CAD. In this meta-analysis, we evaluated the predictive role of APV in CAD.

MATERIAL AND METHODS

Relevant electronic bibliographies (PubMed, ScienceDirect, Scopus, EMbase, the Cochrane library) were explored. Related reports were selected according to the inclusion and exclusion criteria. Meta-analysis was performed using the Comprehensive Meta-analysis 2.0 software.

RESULTS

Eventually, 5 articles met the inclusion criteria and included in the meta-analysis. Five studies with 490 patients reported the APV mean in CAD and non-CAD groups. A random-effect model was used and the pooled findings demonstrated a significant higher APV in non-CAD group compared to CAD group (SMD: 2.39, 95% CI: 1.70-3.07, P < .001, I2: 84%, Q: 19.03). The diagnostic value of APV in predicting CAD showed 86.3% sensitivity (95% CI: 74-91, P value < .001, I2: 65%, Q: 8.53, P value: .03) and 83.8% specificity (95% CI: 69-94, P value < .001, I2: 60%, Q: 9.89, P value: .01).

CONCLUSION

There was a predictive role of APV in CAD with suitable specificity and sensitivity. Moreover, aortic distensibility and aortic strain were significantly different in CAD and non-CAD patients. APV could be used as a good noninvasive tool for screening CAD.

Serum Uric Acid Levels Are Associated with the Echogenic Features of Carotid Plaque Vulnerability in Elderly Patients with Atherosclerotic Disease

Uric acid is a marker of inflammation and a risk factor for atherosclerosis that has been suggested to play a role in carotid plaque instability. Reduced atherosclerotic plaque echogenicity at ultrasound examination is associated with alarming histopathological features and inflammation. In this study, we investigated the relationship between serum uric acid (SUA) levels and echogenic patterns of plaque instability in elderly subjects with carotid atherosclerosis. Since uric acid metabolism largely depends on renal function, SUA levels were indexed for serum creatinine levels (SUA/SCr). We enrolled 108 patients aged 65 years or more (72.7 ± 5.9 years; 50 females and 58 males) who underwent carotid duplex ultrasound to evaluate plaque echogenicity by greyscale median (GSM). The regression analysis demonstrated a significant inverse association between the GSM and the SUA/SCr ratio (β: -0.567; 95% CI -0.751 to -0.384 and p < 0.0001). Stepwise multivariate regression showed that the SUA/SCr ratio explained 30.3% of GSM variability (β: -0.600; 95% CI -0.777/-0.424, p < 0.0001, and semi-partial correlation 0.303). After a mean period of 3.5 ± 0.5 years, 48 patients were reevaluated according to the same baseline study protocol. The regression analysis demonstrated a still significant inverse association between the GSM and the SUA/SCr ratio (β: -0.462; 95% CI -0.745 to -0.178 and p = 0.002). Stepwise multivariate regression showed that the SUA/SCr ratio explained 28.0% of GSM variability (coefficient -0.584, 95% CI -0.848/-0.319, p < 0.0001, and semi-partial R² 0.280). In conclusion, this study demonstrates that SUA levels indexed for serum creatinine are associated with the echogenic features of carotid plaque vulnerability in elderly patients with atherosclerotic disease. These data could suggest an influential role for uric acid metabolism in carotid plaque biology.

Enhanced Carotid Plaque Echolucency Is Associated with Reduced Cognitive Performance in Elderly Patients with Atherosclerotic Disease Independently on Metabolic Profile

Vulnerable carotid atherosclerotic plaques are related to an increased risk of cognitive impairment and dementia in advanced age. In this study, we investigated the relationship between the echogenicity of carotid plaques and cognitive performance in patients with asymptomatic carotid atherosclerotic plaques. We enrolled 113 patients aged 65 years or more (72.4 ± 5.9 years) who underwent carotid duplex ultrasound to evaluate plaque echogenicity by grey-scale median (GSM) and neuropsychological tests to assess cognitive function. The GSM values at baseline were inversely correlated with the number of seconds required to complete Trail Makin Test (TMT) A (rho: −0.442; p < 0.0001), TMT B (rho: −0.460; p < 0.0001) and TMT B-A (rho: −0.333; p < 0.0001) and directly correlated with Mini Mental State Examination (MMSE) and Verbal Fluency Test (VFT) score (rho: 0.217; p = 0.021 and rho: 0.375; p < 0.0001, respectively) and the composite cognitive z-score (rho: 0.464; p < 0.0001). After a mean period of 3.5 ± 0.5 years, 55 patients were reevaluated according to the same baseline study protocol. Patients with baseline GSM value higher than the median value of 29 did not show any significant variation in the z-score. Instead, those with GSM ≤ 29 showed a significant worsening of z-score (−1.2; p = 0.0258). In conclusion, this study demonstrates the existence of an inverse relationship between the echolucency of carotid plaques and cognitive function in elderly patients with atherosclerotic carotid disease. These data suggest that the assessment of plaque echogenicity if used appropriately, might aid in identifying subjects at increased risk for cognitive dysfunction.

lncRNA PCA3 Suppressed Carotid Artery Stenosis and Vascular Smooth Muscle Cell Function via Negatively Modulating the miR-124-3p/ITGB1 Axis

BACKGROUND & OBJECTIVES

Due to the hidden pathogen, carotid artery stenosis (CAS) always occurred at an advanced stage leading to serious sequelae and even deaths. The significance of long noncoding RNA (lncRNA) prostate cancer antigen 3 (PCA3) in CAS incidence and progression were evaluated aiming to explore a potential target for its therapy.

MATERIALS AND METHODS

Serum samples were collected from 83 asymptomatic CAS patients and 52 healthy individuals and PCA3 was compared using polymerase chain reaction (PCR). The PCA3 levels were compared between stable and unstable plaque in CAS patients. The effect of PCA3 on vascular smooth muscle cells (VSMCs) proliferation and motility was assessed by CCK8 and transwell assay.

RESULTS

PCA3 was downregulated in CAS patients and their unstable plaque tissues compared with healthy individuals and stable plaque, respectively. Reduced PCA3 could discriminate CAS patients with relatively high sensitivity and specificity and were associated with higher total cholesterol level and stenosis degree, unstable plaque, and complications. PCA3 downregulation predicted the adverse outcomes of CAS patients. In VSMCs, overexpressing PCA3 significantly suppressed cell proliferation, migration, and invasion, which was alleviated by miR-124-3p/ITGB1 axis.

CONCLUSION

PCA3 served as a biomarker of CAS and regulates the function of VSMCs through sponging miR-124-3p/ITGB1 and indirectly influence the stability of plaque.

The Correlation between Increased Expressions of NLRP3 Inflammasome Components in Peripheral Blood Mono-Nuclear Cells and Plaque Vulnerability in Human Carotid Atherosclerosis

Background

We aimed to determine whether NLRP3 inflammasomes in peripheral blood mononuclear cells (PBMC) were associated with carotid plaque instability in carotid atherosclerosis patients.

Methods

Consecutive 38 carotid atherosclerosis with vulnerable plaques, 22 carotid atherosclerosis with stable plaques, and 40 healthy subjects with no carotid or coronary artery stenosis were enrolled. They were referred to the Second Hospital of Dalian Medical University from 2013-2019. Carotid plaques were evaluated by modified plaque vulnerability risk score (MPVRS) and pathological assessment. The mRNA and protein expression of NLRP3 inflammasome components in PBMC were determined by quantitative real time PCR and Western blot analysis or ELISA.

Results

When consecutive study subjects undergoing carotid endarterectomy were divided into stable (≤4) and unstable (>4) plaque groups according to the MPVRS, the unstable plaque group had significantly raised mRNA and protein expression of NLRP3 inflammasome components in PBMC as compared with the stable plaque group and healthy subject group. Furthermore, subjects with higher NLRP3 protein expression in PBMC had greater incidence of cerebrovascular events.

Conclusion

Increased NLRP3 inflammasome components in PBMC is associated with instability of human carotid atherosclerotic plaques, suggesting NLRP3 inflammasome as a potential biomarker for monitoring carotid plaque instability.

The Unstable Carotid Plaque

Carotid revascularization is performed to prevent cerebrovascular events in patients with symptomatic (>50%) and asymptomatic high degree (>70%) carotid stenosis. As this operation carries significant risks for perioperative stroke, careful selection of patients who will benefit from the procedure is essential. Certain plaque characteristics, including texture, are associated with increased tendency for rupture and can be used to identify high-risk patients. Medical therapy, carotid endarterectomy, and carotid stenting are the mainstays for patient management. With careful selection of patients, all anesthesia techniques (general anesthesia, monitored anesthesia care, and regional anesthesia) can be used safely for these revascularization procedures.

Non-Coding RNAs in Regulating Plaque Progression and Remodeling of Extracellular Matrix in Atherosclerosis

Non-coding RNAs (ncRNAs) regulate cell proliferation, migration, differentiation, inflammation, metabolism of clinically important biomolecules, and other cellular processes. They do not encode proteins but are involved in the regulatory network of various proteins that are directly related to the pathogenesis of diseases. Little is known about the ncRNA-associated mechanisms of atherosclerosis and related cardiovascular disorders. Remodeling of the extracellular matrix (ECM) is critical in the pathogenesis of atherosclerosis and related disorders; however, its regulatory proteins are the potential subjects to explore with special emphasis on epigenetic regulatory components. The activity of regulatory proteins involved in ECM remodeling is regulated by various ncRNA molecules, as evident from recent research. Thus, it is important to critically evaluate the existing literature to enhance the understanding of nc-RNAs-regulated molecular mechanisms regulating ECM components, remodeling, and progression of atherosclerosis. This is crucial since deregulated ECM remodeling contributes to atherosclerosis. Thus, an in-depth understanding of ncRNA-associated ECM remodeling may identify novel targets for the treatment of atherosclerosis and other cardiovascular diseases.

Dynamic Changes of Carotid Atherosclerosis and Their Relation with Stroke Recurrence in Patients with Stroke or Transient Ischemic Attack

BACKGROUND AND PURPOSE

The purpose of this study was to show dynamic changes in carotid and vertebral artery using carotid Doppler ultrasonography (DUS) through a long-term follow- up exam, and determine their associations with stroke recurrence.

METHODS

We consecutively enrolled stroke or transient ischemic attack (TIA) patients who had undergone DUS more than twice with intervals of three months or more. Stroke recurrence during follow-up was also investigated by reviewing medical records. Progress or regress of plaque was defined as more than 0.1 mm change from the initial scan with a semi-quantitative measurement. The development of new plaque was also regarded as plaque progress. Increased intima-media thickness and plaque presence were interpreted at the initial and follow-up scans. Factors related to progression or regression were analyzed. The relationship between plaque change and stroke recurrence was investigated.

RESULTS

A total of 201 patients were enrolled (186 ischemic stroke patients and 15 TIA patients). There were 61 (30.3%) females. Their mean age was 64.2 ± 9.9 years. During a follow-up of 35.0 ± 22.6 (mean ± SD) months, plaque progress was observed in 92 (45.8%) and plaque regress in 13 (6.5%). Stroke recurred in 18 patients. Plaque progression showed no significant association with age, risk factors, statin use, or subtype. After adjustment of age, sex, diabetes, and stroke subtype, multiple logistic regression showed a significant association of plaque progression with stroke recurrence (odds ratio: 3.8, 95% confidence interval: 1.1 to 13.1, p = 0.034). Patients with plaque regress were significantly younger than those without plaque regress (57.8 years vs. 64.6 years, p = 0.041).

CONCLUSION

Plaque progression occurred in 46% of stroke or TIA patients. Plaque progression was significantly associated with clinical stroke recurrence. Plaque regressed in 6.5% of patients. Patients with regression were younger than those without.

Clinical Parameters and Epigenetic Biomarkers of Plaque Vulnerability in Patients with Carotid Stenosis

Atheromatous disease is the first cause of death and dependency in developed countries and carotid artery atherosclerosis is one of the main causes of severe ischaemic strokes. Current management strategies are mainly based on the degree of stenosis and patient selection has limited accuracy. This information could be complemented by the identification of biomarkers of plaque vulnerability, which would permit patients at greater and lesser risk of stroke to be distinguished, thus enabling a better selection of patients for surgical or intensive medical treatment. Although several circulating protein-based biomarkers with significance for both the diagnosis of carotid artery disease and its prognosis have been identified, at present, none have been clinically implemented. This review focuses especially on the most relevant clinical parameters to take into account in routine clinical practice and summarises the most up-to-date data on epigenetic biomarkers of carotid atherosclerosis and plaque vulnerability.

Current advances in the imaging of atherosclerotic vulnerable plaque using nanoparticles

Vulnerable atherosclerotic plaques of the artery wall that pose a significant risk of cardio-cerebral vascular accidents remain the global leading cause of morbidity and mortality. Thus, early delineation of vulnerable atherosclerotic plaques is of clinical importance for prevention and treatment. The currently available imaging technologies mainly focus on the structural assessment of the vascular wall. Unfortunately, several disadvantages in these strategies limit the improvement in imaging effect. Nanoparticle technology is a novel diagnostic strategy for targeting and imaging pathological biomarkers. New functionalized nanoparticles that detect hallmarks of vulnerable plaques are promising for advance further control of this critical illness. The review aims to address the current opportunities and challenges for the use of nanoparticle technology in imagining vulnerable plaques.

Markers of Carotid Plaque Destabilization in Patients With Sleep-Disordered Breathing

Sleep-disordered breathing (SDB) is a nightly respiratory condition characterized by intermittent hypoxia, leading to oxidative stress, inflammation, and atherosclerosis. However, most cellular markers of human carotid plaques in SDB have not yet been assessed. We aimed at characterizing the cellular, inflammatory, and nitro-oxidative stress markers in carotid plaques obtained from 25 patients undergoing endarterectomy and screened for SDB. Sleep studies were performed during their preoperative hospitalization night using the Watch-PAT 100 device. Oxygen desaturation index (ODI) was used for dividing patients into two groups. Fourteen patients with ODI >5 were designated as SDB and 11 patients with ODI ≤ 5 as non-SDB. Demographics, comorbidities, cardiovascular risk factors, and medications were recorded. Cellular markers in plaques were analyzed by immunofluorescence using confocal microscopy. The expression of neutrophils was identified by CD66b+ and neutrophil elastase, macrophage-foam cells were identified by CD163+, and scavenger receptors by CD68+ and CD36+ expression. Additional markers included 3-nitrotyrosine, endothelial CD31, and smooth muscle cell-actin (SMC-actin). Plaques' lipids were determined by immunohistochemistry with Oil Red O staining. Notably, significantly higher values were found for SDB as compared to patients with non-SDB for 3-nitrotyrosine (p <0.004) and intracellular lipids' content (p <0.02), whereas SMC-actin was lower (p <0.006). There were no significant differences between patients with carotid-associated symptoms (symptomatic) and patients without carotid-associated symptoms (asymptomatic). However, a sub-group of symptomatic patients with co-existent SDB expressed the highest 3-nitrotyrosin, and intracellular lipids levels, and the lowest SMC-actin levels, whereas non-SDB/asymptomatic patients expressed the lowest 3-nitrotyrosin and lipids levels and the highest SMS-actin levels among all patients. Accordingly, ODI was lowest in non-SDB/asymptomatic patients and highest in SDB/symptomatic. In conclusion, plaques of patients with SDB were characterized by markedly increased levels of 3-nitrotyrosine and intracellular lipids content. Conversely, SMC-actin levels were significantly lower. These three markers, such as increased 3-nitrotyrosine and intracellular lipids and decreased SMC-actin are associated with plaque vulnerability and instability. These findings are in line with earlier reports demonstrating increased intima-media thickness in large cohorts of sleep apnea and patients with SDB, and thus, may indicate a higher susceptibility to plaque vulnerability and rapture in patients with SDB.

Progerin mislocalizes myocardin-related transcription factor in Hutchinson-Guilford Progeria syndrome

Hutchinson-Guilford Progeria syndrome (HGPS) is a rare genetic disease of premature aging and early death due to cardiovascular disease. The arteries of HGPS children and mice are pathologically stiff, and HGPS mice also display reduced arterial contractility. We recently showed that reduced contractility is an early event in HGPS and linked to an aberrantly low expression of smooth muscle myosin heavy chain (smMHC). Here, we have explored the basis for reduced smMHC abundance and asked whether it is a direct effect of progerin expression or a longer-term adaptive response. Myh11, the gene encoding for smMHC, is regulated by myocardin-related transcription factors (MRTFs), and we show that HGPS aortas have a reduced MRTF signature. Additionally, smooth muscle cells (SMCs) isolated from HGPS mice display reduced MRTF nuclear localization. Acute progerin expression in WT SMCs phenocopied both the decrease in MRTF nuclear localization and expression of Myh11 seen in HGPS. Interestingly, RNA-mediated depletion of MRTF-A in WT SMCs reproduced the preferential inhibitory effect of progerin on Myh11 mRNA relative to Acta2 mRNA. Our results show that progerin expression acutely disrupts MRTF localization to the nucleus and suggest that the consequent decrease in nuclear coactivator activity can help to explain the reduction in smMHC abundance and SMC contractility seen in HGPS.