Atherosclerotic Samples Research Articles

Examining the Relationship: Porphyromonas gingivalis Presence in Subgingival and Atherosclerotic Plaques of Cadavers

Background: Atherosclerosis and periodontitis are chronic inflammatory diseases characterized by inflammation and tissue destruction. Porphyromonas gingivalis, a key pathogen in periodontal disease, is implicated in initiating inflammation and tissue damage. Objectives: Given the potential link between periodontitis and the development of atherosclerotic plaques, this study aimed to investigate the presence of P. gingivalis DNA in subgingival and atherosclerotic plaques obtained from cadavers at the Tehran Forensic Medicine Center. Methods: In this cross-sectional study, cadavers with a postmortem interval of 6 hours and atherosclerotic plaques in their coronary arteries, along with subgingival plaques exhibiting pocket depths exceeding 5 mm, were examined. Subgingival plaque samples were collected from the deepest sites, while atherosclerotic plaque samples were harvested. Real-time PCR was employed to detect the presence of P. gingivalis in all samples, and the McNemar test was used for data analysis. Results: A total of 25 cadavers were included in the analysis, and both subgingival and atherosclerotic plaque samples were assessed. P. gingivalis DNA was identified in 40% of subgingival plaque samples and 16% of atherosclerotic plaque samples. Moreover, all positive atherosclerotic plaque samples also tested positive for P. gingivalis in the subgingival plaque. McNemar's analysis revealed a statistically significant difference between the subgingival and atherosclerotic samples (P-value = 0.03). Additionally, a correlation coefficient of 0.53 was obtained. Conclusions: While the study has certain limitations, the findings indicate a significant association between the presence of P. gingivalis in subgingival and coronary atherosclerotic plaques. Further investigations are warranted to elucidate the precise role of this periopathogen in atherosclerotic plaque formation.

Local vascular Klotho mediates diabetes-induced atherosclerosis via ERK1/2 and PI3-kinase-dependent signaling pathways

Background and aimsDiabetes is one of the major causes of cardiovascular disease (CVD). As high as 29 % of patients with diabetes develop atherosclerosis. Vascular Smooth Muscle Cells (VSMCs) are a key mediator in the pathogenesis of atherosclerosis, generating pro-inflammatory and proliferative characteristics in atherosclerotic lesions. MethodsWe used human atherosclerotic samples, developed diabetes-induced atherosclerotic mice, and generated loss of function and gain of function in Klotho human aortic smooth muscle cells to investigate the function of Klotho in atherosclerosis. ResultsWe found that Klotho expression is decreased in smooth muscle actin-positive cells in patients with diabetes and atherosclerosis. Consistent with human data, we found that Apoe knockout mice with streptozotocin-induced diabetes fed on a high-fat diet showed decreased expression of Klotho in SMCs. Additionally, these mice showed increased expression of TGF-β, MMP9, phosphorylation of ERK and Akt. Further, we utilized primary Human Aortic Smooth Muscle Cells (HASMCs) with d-glucose under dose-response and in time-dependent conditions to study the role of Klotho in these cells. Klotho gain of function and loss of function studies showed that Klotho inversely regulated the expression of atherosclerotic markers TGF-β, MMP2, MMP9, and Fractalkine.Further, High Glucose (HG) induced Akt, and ERK1/2 phosphorylation were enhanced or mitigated by endogenous Klotho deficiency or its overexpression respectively. PI3K/Akt and MAPK/ERK inhibition partially abolished the HG-induced upregulation of TGF-β, MMP2, MMP9, and Fractalkine. Additionally, Klotho knockdown increased the proliferation of HASMCs and enhanced α-SMA and TGF-β expression. ConclusionsTaken together, these results indicate that local vascular Klotho is involved in diabetes-induced atherosclerosis, which is via PI3K/Akt and ERK1/2-dependent signaling pathways.

Investigating the potential of catheter-assisted pulsed focused ultrasound ablation for atherosclerotic plaques.

Atherosclerosis is a condition in which an adhesive substance called plaque accumulates over time inside the arteries. Plaque buildup results in the constriction of arteries, causing a shortage of blood supply to tissues and organs. Removing atherosclerotic plaques controls the development of acute ischemic stroke and heart diseases. It remains imperative for positive patient outcomes. This study sought to develop a minimally invasive technique for removing arterial plaques by applying focused ultrasound (FUS) energy on the metal surface of a nitinol catheter wire to induce inertial cavitation. The induced cavitation can deplete plaque mechanically inside the arteries, leading towards improved recanalization of blood vessels. The enhanced cavitation effect induced by combining FUS with a metal catheter was first verified by exposing agar phantom gels with or without a 0.9-mm diameter nitinol wire to an acoustic field produced by a 0.5-MHz FUS transducer. The phenomenon was further confirmed in pork belly fat samples with or without a 3-mm diameter nitinol catheter wire. Cavitation was monitored by detecting the peaks of emitted ultrasound signals from the samples using a passive cavitation detector (PCD). Cavitation threshold values were determined by observing the jump in the peak amplitude of signals received by the PCD when the applied FUS peak negative pressure (PNP) increased. To simulate arterial plaque removal, FUS with or without a catheter was used to remove tissues from pork belly fat samples and the lipid cores of human atherosclerotic plaque samples using 2500-cycle FUS bursts at 10% duty cycle and a burst repetition rate of 20Hz. Treatment outcomes were quantified by subtracting the weight of samples before treatment from the weight of samples after treatment. All measurements were repeated 5 times (n=5) unless otherwise indicated, and paired t-tests were used to compare the means of two groups. A p-value of <0.05 will be considered significant. Our results showed that with a nitinol wire, the cavitation threshold in agar phantoms was reduced to 2.6MPa from 4.3MPa PNP when there was no nitinol wire in the focal region of FUS. For pork belly fat samples, cavitation threshold values were 1.0 and 2.0MPa PNP, with and without a catheter wire, respectively. Pork belly fat tissues and lipid cores of atherosclerotic plaques were depleted at the interface between a catheter and the samples at 2 and 4MPa FUS PNP, respectively. The results showed that with a catheter wire in the focal region of a 3-min FUS treatment session, 24.7 and 25.6mg of lipid tissues were removed from pork belly fat and human atherosclerotic samples, respectively. In contrast, the FUS-only group showed no reduction in sample weight. The differences between FUS-only and FUS-plus-catheter groups were statistically significant (p<0.001 for the treatment on pork belly samples, and p<0.01 for the treatment on human atherosclerotic samples). This study demonstrated the feasibility of catheter-assisted FUS therapy for removing atherosclerotic plaques.

Smooth muscle NF90 deficiency ameliorates diabetic atherosclerotic calcification in male mice via FBXW7-AGER1-AGEs axis

Hyperglycemia accelerates calcification of atherosclerotic plaques in diabetic patients, and the accumulation of advanced glycation end products (AGEs) is closely related to the atherosclerotic calcification. Here, we show that hyperglycemia-mediated AGEs markedly increase vascular smooth muscle cells (VSMCs) NF90/110 activation in male diabetic patients with atherosclerotic calcified samples. VSMC-specific NF90/110 knockout in male mice decreases obviously AGEs-induced atherosclerotic calcification, along with the inhibitions of VSMC phenotypic changes to osteoblast-like cells, apoptosis, and matrix vesicle release. Mechanistically, AGEs increase the activity of NF90, which then enhances ubiquitination and degradation of AGE receptor 1 (AGER1) by stabilizing the mRNA of E3 ubiquitin ligase FBXW7, thus causing the accumulation of more AGEs and atherosclerotic calcification. Collectively, our study demonstrates the effects of VSMC NF90 in mediating the metabolic imbalance of AGEs to accelerate diabetic atherosclerotic calcification. Therefore, inhibition of VSMC NF90 may be a potential therapeutic target for diabetic atherosclerotic calcification.

A Novel Macrophage Subpopulation Conveys Increased Genetic Risk of Coronary Artery Disease.

Coronary artery disease (CAD), the leading cause of death worldwide, is influenced by both environmental and genetic factors. Although over 250 genetic risk loci have been identified through genome-wide association studies, the specific causal variants and their regulatory mechanisms are still largely unknown, particularly in disease-relevant cell types such as macrophages. We utilized single-cell RNA-seq and single-cell multiomics approaches in primary human monocyte-derived macrophages to explore the transcriptional regulatory network involved in a critical pathogenic event of coronary atherosclerosis-the formation of lipid-laden foam cells. The relative genetic contribution to CAD was assessed by partitioning disease heritability across different macrophage subpopulations. Meta-analysis of single-cell RNA-seq data sets from 38 human atherosclerotic samples was conducted to provide high-resolution cross-referencing to macrophage subpopulations in vivo. We identified 18 782 cis-regulatory elements by jointly profiling the gene expression and chromatin accessibility of >5000 macrophages. Integration with CAD genome-wide association study data prioritized 121 CAD-related genetic variants and 56 candidate causal genes. We showed that CAD heritability was not uniformly distributed and was particularly enriched in the gene programs of a novel CD52-hi lipid-handling macrophage subpopulation. These CD52-hi macrophages displayed significantly less lipoprotein accumulation and were also found in human atherosclerotic plaques. We investigated the cis-regulatory effect of a risk variant rs10488763 on FDX1, implicating the recruitment of AP-1 and C/EBP-β in the causal mechanisms at this locus. Our results provide genetic evidence of the divergent roles of macrophage subsets in atherogenesis and highlight lipid-handling macrophages as a key subpopulation through which genetic variants operate to influence disease. These findings provide an unbiased framework for functional fine-mapping of genome-wide association study results using single-cell multiomics and offer new insights into the genotype-environment interactions underlying atherosclerotic disease.

Transcriptomic analysis reveals molecular characterization and immune landscape of PANoptosis-related genes in atherosclerosis.

Atherosclerosis is a chronic inflammatory disease characterized by abnormal lipid deposition in the arteries. Programmed cell death is involved in the inflammatory response of atherosclerosis, but PANoptosis, as a new form of programmed cell death, is still unclear in atherosclerosis. This study explored the key PANoptosis-related genes involved in atherosclerosis and their potential mechanisms through bioinformatics analysis. We evaluated differentially expressed genes (DEGs) and immune infiltration landscape in atherosclerosis using microarray datasets and bioinformatics analysis. By intersecting PANoptosis-related genes from the GeneCards database with DEGs, we obtained a set of PANoptosis-related genes in atherosclerosis (PANoDEGs). Functional enrichment analysis of PANoDEGs was performed and protein-protein interaction (PPI) network of PANoDEGs was established. The machine learning algorithms were used to identify the key PANoDEGs closely linked to atherosclerosis. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic potency of key PANoDEGs. CIBERSORT was used to analyze the immune infiltration patterns in atherosclerosis, and the Spearman method was used to study the relationship between key PANoDEGs and immune infiltration abundance. The single gene enrichment analysis of key PANoDEGs was investigated by GSEA. The transcription factors and target miRNAs of key PANoDEGs were predicted by Cytoscape and online database, respectively. The expression of key PANoDEGs was validated through animal and cell experiments. PANoDEGs in atherosclerosis were significantly enriched in apoptotic process, pyroptosis, necroptosis, cytosolic DNA-sensing pathway, NOD-like receptor signaling pathway, lipid and atherosclerosis. Four key PANoDEGs (ZBP1, SNHG6, DNM1L, and AIM2) were found to be closely related to atherosclerosis. The ROC curve analysis demonstrated that the key PANoDEGs had a strong diagnostic potential in distinguishing atherosclerotic samples from control samples. Immune cell infiltration analysis revealed that the proportion of initial B cells, plasma cells, CD4 memory resting T cells, and M1 macrophages was significantly higher in atherosclerotic tissues compared to normal tissues. Spearman analysis showed that key PANoDEGs showed strong correlations with immune cells such as T cells, macrophages, plasma cells, and mast cells. The regulatory networks of the four key PANoDEGs were established. The expression of key PANoDEGs was verified in further cell and animal experiments. This study evaluated the expression changes of PANoptosis-related genes in atherosclerosis, providing a reference direction for the study of PANoptosis in atherosclerosis and offering potential new avenues for further understanding the pathogenesis and treatment strategies of atherosclerosis.

Atherosclerotic Calcifications Have a Local Effect on the Peel Behavior of Human Aortic Media.

Aortic dissections, characterized by the propagation of a tear through the layers of the vessel wall, are critical, life-threatening events. Aortic calcifications are a common comorbidity in both acute and chronic dissections, yet their impact on dissection mechanics remains unclear. Using micro-computed tomography (CT) imaging, peel testing, and finite element modeling, this study examines the interplay between atherosclerotic calcifications and dissection mechanics. Samples cut from cadaveric human thoracic aortas were micro-CT imaged and subsequently peel-tested to map peel tension curves to the location of aortic calcifications. Empirical mode decomposition separated peel tension curves into high and low-frequency components, with high-frequency effects corresponding to interlamellar bonding mechanics and low-frequency effects to peel tension fluctuations. Finally, we used an idealized finite element model to examine how stiff calcifications affect aortic failure mechanics. Results showed that atherosclerosis influences dissection behavior on multiple length scales. Experimentally, atherosclerotic samples exhibited higher peel tensions and greater variance in the axial direction. The variation was driven by increased amplitudes of low-frequency tension fluctuations in diseased samples, indicating that more catastrophic propagations occur near calcifications. The simulations corroborated this finding, suggesting that the low-frequency changes resulted from the presence of a stiff calcification in the vessel wall. There were also modifications to the high-frequency peel mechanics, a response likely attributable to alterations in the microstructure and interlamellar bonding within the media. Considered collectively, these findings demonstrate that dissection mechanics are modified in aortic media nearby and adjacent to aortic calcifications.

Role of miR-15a-5p and miR-199a-3p in the inflammatory pathway regulated by NF-κB in experimental and human atherosclerosis.

Cardiovascular diseases (CVDs) prevalence has significantly increased in the last decade and atherosclerosis development is the main trigger. MicroRNAs (miRNAs) are non-coding RNAs that negatively regulate gene expression of their target and their levels are frequently altered in CVDs. By RT-qPCR, we analysed miR-9-5p, miR-15a-5p, miR-16-5p and miR-199a-3p levels in aorta from apolipoprotein knockout (ApoE-/- ) mice, an experimental model of hyperlipidemia-induced atherosclerosis, and in human aortic and carotid atherosclerotic samples. By in silico studies, Western blot analysis and immunofluorescence studies, we detected the targets of the altered miRNAs. Our results show that miR-15a-5p and miR-199a-3p are significantly decreased in carotid and aortic samples from patients and mice with atherosclerosis. In addition, we found an increased expression in targets of both miRNAs that participate in the inflammatory pathway of nuclear factor kappa B (NF-κB), such as IKKα, IKKβ and p65. In human vein endothelial cells (HUVECs) and vascular smooth muscle cells (VSMCs), the overexpression of miR-15a-5p or miR-199a-3p decreased IKKα, IKKβ and p65 protein levels as well as NF-κB activation. On the other hand, miR-15a-5p and miR-199a-3p overexpression reduced ox-LDL uptake and the inflammation regulated by NF-κB in VSMCs. Moreover, although miR-15a-5p and miR-199a-3p were significantly increased in exosomes from patients with advanced carotid atherosclerosis, only in the ROC analyses for miR-15a-5p, the area under the curve was 0.8951 with a p value of .0028. Our results suggest that the decrease of miR-199a-3p and miR-15a-5p in vascular samples from human and experimental atherosclerosis could be involved in the NF-κB activation pathway, as well as in ox-LDL uptake by VSMCs, contributing to inflammation and progression atherosclerosis. Finally, miR-15a-5p could be used as a novel diagnostic biomarker for advanced atherosclerosis.

Nuclear FAK in endothelium: An intrinsic inhibitor of NF-κB activation in atherosclerosis

Background and aimsHyperlipidemia leads to the accumulation of oxidized low-density lipoprotein (oxLDL) within the vessel wall where it causes chronic inflammation in endothelial cells (ECs) and drives atherosclerotic lesions. Although focal adhesion kinase (FAK) is critical in proinflammatory NF-κB activation in ECs, it is unknown if hyperlipidemia alters FAK-mediated NF-κB activity in vivo to affect atherosclerosis progression. MethodsWe investigated changes in EC FAK and NF-κB activation using Apoe−/− mice fed a western diet (WD). Both pharmacological FAK inhibition and EC-specific FAK inhibited mouse models were utilized. FAK and NF-κB localization and activity were also analyzed in human atherosclerotic samples. ResultsECs of hyperlipidemic mice clearly showed much higher levels of FAK activation in the cytoplasm, which was associated with increased NF-κB activation compared to normal diet (ND) group. On the contrary, FAK is mostly localized in the nucleus and inactive in ECs under healthy conditions with a low NF-κB activity. Both pharmacological and EC-specific genetic FAK inhibition in WD fed Apoe−/− mice exhibited a significant decrease in FAK activity and cytoplasmic localization, NF-κB activation, macrophage recruitment, and atherosclerotic lesions compared to the vehicle or FAK wild-type groups. Analyses of human atherosclerotic specimens revealed a positive correlation between increased active cytoplasmic FAK within ECs and NF-κB activation in the lesions. ConclusionsHyperlipidemic conditions activate NF-κB pathway by increasing EC FAK activity and cytoplasmic localization in mice and human atherosclerotic samples. As FAK inhibition can efficiently reduce vascular inflammation and atherosclerotic lesions in mice by reversing EC FAK localization and NF-κB activation, these findings support a potential use for FAK inhibitors in treating atherosclerosis.

Hyperuricemia promotes the progression of atherosclerosis by activating endothelial cell pyroptosis via the ROS/NLRP3 pathway.

Hyperuricemia closely correlates with the development of atherosclerosis, but little is known of the mechanism by which atherosclerosis progression occurs in hyperuricemia. Atherosclerosis appears to involve pyroptosis, an emerging mechanism of proinflammatory regulated cell death. This study tested the hypothesis that pyroptosis underlies the relationship between hyperuricemia and atherosclerosis, using ApoE-/- mice (a model of atherosclerosis), human umbilical vein endothelial cells (HUVECs), and human atherosclerotic arterial samples. We found that hyperuricemia can aggravate the aortic atherosclerotic plaque-load in ApoE-/- mice and promote endothelial cell pyroptosis. Additionally, hyperuricemia can increase the levels of serum inflammatory factors (including IL-1β and IL-18). Exposure to lipopolysaccharideplus a high concentration of soluble uric acid (≥12 mg/dL) induced cell pyroptosis in HUVECs, as evidenced by increased expression of pyroptosis-related proteins and elevated release of lactate dehydrogenase (a marker of tissue damage). Further, MCC950, a selective nucleotide-binding oligomerization domain (NOD)-like receptor 3(NLRP3) inflammasome inhibitor, and N-acetyl- l-cysteine, an antioxidant, attenuated HUVEC pyroptosis by inhibiting activation of the NLRP3 inflammasome and production of intracellular reactive oxygen species (ROS). Finally, we detected significantly higher expression of pyroptosis-associated proteins in carotid specimens from patients with hyperuricemia. Collectively, our findings suggest that hyperuricemia can aggravate endothelial cell pyroptosis in aortic atherosclerotic plaques, promoting the development of atherosclerosis. Additionally, a high concentration of soluble uric acid can trigger the activation stage of the NLRP3 inflammasome, mediating endothelial cell pyroptosis, and this process is regulated by the cellular ROS level.

The translational landscape of human vascular smooth muscle cells identifies novel short open reading frame-encoded peptide regulators for phenotype alteration.

The plasticity of vascular smooth muscle cells (VSMCs) enables them to alter phenotypes under various physiological and pathological stimuli. The alteration of VSMC phenotype is a key step in vascular diseases, including atherosclerosis. Although the transcriptome shift during VSMC phenotype alteration has been intensively investigated, uncovering multiple key regulatory signalling pathways, the translatome dynamics in this cellular process, remain largely unknown. Here, we explored the genome-wide regulation at the translational level of human VSMCs during phenotype alteration. We generated nucleotide-resolution translatome and transcriptome data from human VSMCs undergoing phenotype alteration. Deep sequencing of ribosome-protected fragments (Ribo-seq) revealed alterations in protein synthesis independent of changes in messenger ribonucleicacid levels. Increased translational efficiency of many translational machinery components, including ribosomal proteins, eukaryotic translation elongation factors and initiation factors were observed during the phenotype alteration of VSMCs. In addition, hundreds of candidates for short open reading frame-encoded polypeptides (SEPs), a class of peptides containing 200 amino acids or less, were identified in a combined analysis of translatome and transcriptome data with a high positive rate in validating their coding capability. Three evolutionarily conserved SEPs were further detected endogenously by customized antibodies and suggested to participate in the pathogenesis of atherosclerosis by analysing the transcriptome and single cell RNA-seq data from patient atherosclerotic artery samples. Gain- and loss-of-function studies in human VSMCs and genetically engineered mice showed that these SEPs modulate the alteration of VSMC phenotype through different signalling pathways, including the mitogen-activated protein kinase pathway and p53 pathway. Our study indicates that an increase in the capacity of translation, which is attributable to an increased quantity of translational machinery components, mainly controls alterations of VSMC phenotype at the level of translational regulation. In addition, SEPs could function as important regulators in the phenotype alteration of human VSMCs.

Macrophage-specific autophagy-related gene HSPB8 is involved in the macrophage polarization in atherosclerosis

BackgroundAtherosclerosis (AS) is a chronic inflammatory disease, as a main cause leading to vascular diseases worldwide. Although increasing studies have focused on macrophages in AS, the exact relating mechanism is still largely unclear. Our study aimed to explore the pathogenic role and diagnostic role of macrophage autophagy related genes (MARGs) in AS.MethodsAll datasets were downloaded from Gene Expression Omnibus database and Human Autophagy Database. The differential expression analysis and cross analysis were performed to identify candidate MARGs. GO and KEGG enrichment analyses were conducted to obtain the functional information. Moreover, we analyzed the correlation between target gene and macrophage polarization in AS. The correlation between target gene and plaque instability, different stages of AS were also analyzed.ResultsCompared with normal samples, a total of 575 differentially expressed genes (DEGs) were identified in AS samples. A total of 12 overlapped genes were obtained after cross-analysis of the above 575 DEGs and autophagy related genes (ARGs). Then, 10 MARGs were identified in AS samples, which were significantly enriched in 22 KEGG pathways and 61 GO terms. The expression of HSPB8 was significantly down-regulated in atherosclerotic samples compared with normal samples (with largest fold change). Meanwhile, the proportion of M-CSF in low HSPB8 expression AS group was higher than high expression AS group. Furthermore, the expression of HSPB8 was negatively correlated with most inflammatory factors.ConclusionThe downregulation of MARG HSPB8 probably involves in the M2 macrophage polarization in AS samples. HSPB8 is a promising diagnostic marker for AS patients.

Prevalence and association of mycoplasma infection in the development of coronary artery disease.

Coronary heart disease (CHD) has been associated with significant morbidity and mortality worldwide. Although remain controversial, several studies have demonstrated the association of M. pneumoniae infections with atherosclerosis. We evaluated the possible association of mycoplasma infections in patients diagnosed with atherosclerosis by ELISA and PCR methods. Atherosclerotic tissue samples and blood samples were collected for the detection of mycoplasma antibodies (IgA) by ELISA from the 97 patients with coronary artery disease (CAD). M. pneumoniae specific IgA, IgG and IgM were measured by using the Anti-M. pneumoniae IgA/IgG/IgM ELISA. Detection of M. pneumoniae targeting the P1 adhesion gene was performed by PCR Acute infection of M. pneumoniae was diagnosed in 43.3% (42) of patients by PCR. The M. pneumoniae specific antibodies were detected in 36.1% (35) of patients. Twenty-five (25.8%) cases had IgG antibodies, 15 (15.5%) cases had IgM antibodies, 3 (3.1%) cases had IgA antibodies, 10 (10.3%) cases had both IgM + IgG antibodies and 1 (1%) case of each had IgM + IgA and IgG + IgA antibodies. None of the cases was positive for all three antibodies. A Pearson correlation coefficient analysis revealed an excellent correlation between the PCR and the serological results (r=0.921, p<0.001). A majority (17, 40.5%) of the M. pneumoniae positive patients are within the 41-50 years of age group, followed by 10 (23.8%) patients in the age group of 61-70 years and 2 (4.8%) patients were >70 years of age. Our study reported an unusually higher prevalence of M. pneumoniae by serological tests (36.1%) and PCR (43.3%). Although the hypothesis of the association of M. pneumoniae and CAD is yet to be proven, the unusually high prevalence of M. pneumoniae in CAD patients indicates an association, if not, in the development of atherosclerosis.

Comprehensive assessment of markers of apoptosis and cell proliferation during progression of atherosclerosis after surgery in patients with peripheral arterial disease.

Determination of predictors that can affect development of atherosclerosis progression in the postoperative period is an urgent problem in vascular surgery. Integrated assessment of markers of apoptosis and cell proliferation in atherosclerotic lesions and their progression after surgery in patients with peripheral arterial diseases. The investigation included 30 patients with stage IIB-III peripheral arterial disease. All patients have undergone open surgical interventions on the arteries of the aorto-iliac and femoral-popliteal segments. During these interventions, intraoperative specimens were obtained from the vascular wall with atherosclerotic lesions. The following values were evaluated: VEGF А165, PDGF BB, and sFas. Samples of normal vascular wall were obtained from post-mortem donors and used as a control group. The levels of Bax and p53 were increased (p<0.001) in samples from arterial wall with atherosclerotic plaque, while sFas values were reduced (p<0.001), compared to their levels in control samples. Values of PDGF BB and VEGF A165 were 1.9 and 1.7 times higher in atherosclerotic lesion samples (p=0.001), in comparison with the control group. The levels of p53 and Bax were increased against a background of reduced sFas levels in samples with progression of atherosclerosis compared to their baseline values in samples with atherosclerotic plaque (p<0.05). Initially increased values of the Bax marker against a background of reduced sFas values in vascular wall samples from patients with peripheral arterial disease is associated with risk of atherosclerosis progression in the postoperative period.

The underlying molecular mechanisms and biomarkers of plaque vulnerability based on bioinformatics analysis

AimThe study aimed to identify the underlying differentially expressed genes (DEGs) and mechanism of unstable atherosclerotic plaque using bioinformatics methods.MethodsGSE120521, which includes four unstable samples and four stable atherosclerotic samples, was downloaded from the GEO database. DEGs were identified using LIMMA. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of DEGs were performed using the Database for metascape Visualization online tool. Based on the STRING database, protein–protein interactions (PPIs) network among DEGs were constructed. Regulatory networks were visualized using Cytoscape. We use the xCell to analyze the different immune cell subtypes.ResultsA total of 1626 DEGs (1034 up-regulated and 592 down-regulated DEGs) were identified between unstable and stable samples. I pulled 62 transcription factors (34 up-regulated TFs and 28 down-regulated TFs) from the Trust database. The up-regulated TFs were mainly enrichment in positive regulation of myeloid leukocyte differentiation, and the down-regulated TFs were mainly enrichment in connective tissue development. In the PPI network, RB1, CEBPA, PPARG, BATF was the most significantly up-regulated gene in ruptured atherosclerotic samples. The immune cell composition enriched in CD cells and macrophages in the unstable carotid plaque.ConclusionsUpregulated RB1, CEBPA, PPARG, BATF and down-regulated SRF, MYOCD, HEY2, GATA6 might perform critical promotional roles in atherosclerotic plaque rupture, furthermore, number and polarization of macrophages may play an important role in vulnerable plaques.

Abstract P3031: Highly Sensitive Impedance Microsensors Based On Graphene Quantum Dots For The Detection Of Metabolically Active Plaques In Animal Models

Detection of rupture-prone and unstable atherosclerotic lesions is of vital values for patients with acute coronary syndromes or stroke. Despite advances in diagnosis and therapy, sensing of metabolically active but angiographically invisible atherosclerotic lesions remains an unsatisfied clinical challenge but highly desirable. Graphene quantum dots (GQDs) have been widely studied in recent years due to its unique optical and electrical properties, thus providing a huge opportunity for building high-performance sensors. Herein, a highly sensitive impedance microsensor based on platinum nanoparticles (PtNPs) @GQDs was constructed for atherosclerotic lesions assessment, especially for the perception of metabolically active but angiographically invisible atherosclerotic lesions. We designed two-step procedures to prepare PtNPs@GQDs microsensors including electrochemical reduction of GQDs and subsequent electrochemical deposition of ultrafine PtNPs. Atherosclerotic lesions samples at mouse aorta and pig carotid confirm this microsensors with highly sensitive impedance signals and indicated possible atherosclerotic lesions. The equivalent circuits simulation suggested that synergetic PtNPs@GQDs creates more parallel conduction path, thus leading to highly sensitive impedance signals. Our studies offer a universal strategy to prepare high-performance impedance sensors and unique opportunities of translational medicine for early atherosclerotic disease detection and prevention of acute coronary syndromes and stroke.

Integrated Analysis of Gene Expression and Methylation Data to Identify Potential Biomarkers Related to Atherosclerosis Onset.

Atherosclerosis is a kind of chronic inflammatory cardiovascular disease. Epigenetic regulation plays a crucial role in atherosclerosis. Our study was aimed at finding potential biomarkers associated with the occurrence of atherosclerosis. Two datasets were downloaded from the Gene Expression Omnibus (GEO) database. The epigenome-wide association study (EWAS) analysis was performed on methylation data using CpGassoc package. The differential expression analysis was conducted on mRNA data using limma package. The GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) functional enrichment was done in clusterProfiler package. Finally, the logistic regression model was constructed using generalized linear model (glm) function. Between atherosclerotic vs. nonatherosclerotic samples, totally 4980 cytosine-phosphate-guanine (CpG) sites (annotated to 2860 genes) and 132 differentially expressed genes (DEGs) related to atherosclerosis were identified. The annotated 2860 genes and 132 DEGs were significantly enriched in 9 and 4 KEGG pathways and 289 and 132 GO terms, respectively. After cross-analysis, 6 crucial CpG sites were screened to build the model, including cg01187920, cg03422911, cg08018825, cg10967350, cg14473924, and cg25313204. The diagnostic model could reliably separate the atherosclerosis samples from nonatherosclerotic samples. In conclusion, the 6 CpG sites are probably potential diagnostic biomarkers for atherosclerosis, including cg01187920, cg03422911, cg08018825, cg10967350, cg14473924, and cg25313204.

Identification and Validation of Candidate Gene Module Along With Immune Cells Infiltration Patterns in Atherosclerosis Progression to Plaque Rupture via Transcriptome Analysis.

ObjectiveTo explore the differentially expressed genes (DEGs) along with infiltrating immune cells landscape and their potential mechanisms in the progression of atherosclerosis from onset to plaque rupture.MethodsIn this study, three atherosclerosis-related microarray datasets were downloaded from the NCBI-GEO database. The gene set enrichment analysis (GSEA) was performed for interpreting the biological insights of gene expression data. The CIBERSORTx algorithm was applied to infer the relative proportions of infiltrating immune cells of the atherosclerotic samples. DEGs of the datasets were screened using R. The protein interaction network was constructed via STRING. The cluster genes were analyzed by the Cytoscape software. Gene ontology (GO) enrichment was performed via geneontology.org. The least absolute shrinkage and selection operator (LASSO) logistic regression algorithm and receiver operating characteristics (ROC) analyses were performed to build machine learning models for differentiating atherosclerosis status. The Pearson correlation analysis was carried out to illustrate the relationship between cluster genes and immune cells. The expression levels of the cluster genes were validated in two external cohorts. Transcriptional factors and drug-gene interaction analysis were performed to investigate the promising targets for atherosclerosis intervention.ResultsPathways related to immunoinflammatory responses were identified according to GSEA analysis, and the detailed fractions infiltrating immune cells were compared between the early and advanced atherosclerosis. Additionally, we identified 170 DEGs in atherosclerosis progression (|log2FC|≥1 and adjusted p < 0.05). They were mainly enriched in GO terms relating to inflammatory response and innate immune response. A cluster of nine genes, such as ITGB2, C1QC, LY86, CTSS, C1QA, CSF1R, LAPTM5, VSIG4, and CD163, were found to be significant, and their correlations with infiltrating immune cells were calculated. The cluster genes were also validated to be upregulated in two external cohorts. Moreover, C1QA and ITGB2 may exert pathogenic functions in the entire process of atherogenesis.ConclusionsWe reanalyzed the transcriptomic signature of atherosclerosis development from onset to plaque rupture along with the landscape of the immune cell, as well as revealed new insights and specific prospective DEGs for the investigation of disease-associated dynamic molecular processes and their regulations with immune cells.

Pyroptosis-Related Gene Signature and Expression Patterns in the Deterioration of Atherosclerosis.

Background Pyroptosis has been shown to be involved in the overall process of atherosclerosis. This study was aimed at investigating pyroptosis-related gene expression patterns in atherosclerosis and their diagnostic significance. Methods and Results In GSE100927, fifty-four pyroptosis-related genes were identified. Between atherosclerotic plaques and normal samples, the expression patterns of pyroptosis-related genes were significantly different. In order to construct a pyroptosis-related risk score signature (PRSS), the least absolute shrinkage and selection operator (LASSO) was combined with multivariate logistic regression to screen twelve genes. The diagnostic efficiency of the PRSS performed well in GSE43292, as shown by the results of receiver-operating characteristics (ROCs). Consensus clustering identified two expression patterns of pyroptosis-related genes in different statuses of atherosclerotic plaque in GSE163154. The biological behavior of the different clusters was examined by the gene set variation analysis (GSVA). The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses revealed that the differentially expressed genes (DEGs) in the two clusters were enriched in the immune response. The Cytoscape software was used to construct protein-protein interaction (PPI) networks for hub gene screening. Following that, the Drug Gene Interaction Database (DGIdb) was utilized to find 47 possible medicines and chemical compounds that interact with hub genes in atherosclerotic plaques. Conclusion The results of this study showed that pyroptosis-related genes contribute to the progression of atherosclerosis and may serve as biomarkers in clinical diagnosis as well as novel therapeutic targets for the treatment of AS.

Abstract 128: A Chimeric Antigen Receptor Targeting MDA-LDL Activates Regulatory T Cells In The Presence Of Human Atherosclerotic Plaque

Introduction: Regulatory T cells (Tregs) suppress inflammation in atherosclerosis, and therefore have the therapeutic potential to reduce the risk of MI and stroke. However, there is currently no method to generate antigen specific Tregs that target atherosclerosis. We therefore engineered Tregs that express a Chimeric Antigen Receptor (CAR) targeting malonaldehyde-modified LDL (MDA-LDL), the most common form of oxidized LDL and a key molecular component of atherosclerosis. Methods: Novel single chain variable fragments (scFv) were synthesized using sequences from antibodies targeting human MDA-LDL. Oxidized-LDL specific CARs (ox-CARs) were subsequently engineered by fusing each scFv to an IgG4 hinge, CD28 transmembrane and CD28/CD3z cytoplasmic domains. CD4 + CD25 + CD127 low/- Tregs were purified from human blood via FACS and lentivirally transduced to express the novel ox-CARs (ox-CAR-Tregs). Human atherosclerotic plaques were obtained from patients undergoing carotid endarterectomy (CEA). Autologous ox-CAR-Tregs were analyzed for activation after ex-vivo co-culture with CEA samples. Results: A rationally designed panel of 42 ox-CARs were engineered using scFv derived from 12 antibodies targeting MDA-LDL. We first assessed CAR expression and activation in Jurkat T cells to identify promising ox-CAR variants for further evaluation in human Tregs. After culture in the presence of MDA-LDL, six ox-CAR-Treg variants consistently showed significant activation, compared to controls, based on CD71 expression, cytokine expression and proliferation in the absence of CD3/28 stimulation. Human atherosclerotic samples were identified to have substantial amounts of MDA-LDL epitopes using IHC. Autologous ox-CAR-Tregs showed a dose-dependent increase in CD71 expression after ex-vivo co-culture with atherosclerotic plaque. Conclusion: An optimized CAR targeting MDA-LDL activates Tregs when cultured with human atherosclerotic plaque ex-vivo.