Atherosclerotic Formation Research Articles

Chronic Administration of Methamphetamine Aggravates Atherosclerotic Vulnerable Plaques in Apolipoprotein E Knockout Mice Fed with a High-cholesterol Diet.

It has been observed previously that chronic methamphetamine (METH) administration could upregulate neuropeptide Y (NPY) expression and promote atherosclerotic formation in apolipoprotein E knockout (ApoE-/-) mice fed with a normal cholesterol or high diet and NPY might be involved in the pathogenesis of METHinduced atherogenic effects through NPY Y1 receptor pathway. Vulnerable coronary atherosclerotic plaque (VP) is a critical pathological finding responsible for the acute coronary syndrome (ACS). In this study, we explored whether METH abuse could aggravate the formation of VP in ApoE-/- mice fed with high cholesterol diet. The purpose of this study was to observe if chronic METH administration could aggravate vulnerable plaque (VP) formation in ApoE-/- mice fed with a highcholesterol diet. Male ApoE-/- mice fed with a high-cholesterol diet were intraperitoneally injected with normal saline (NS) or 8 mg/kg/day METH (M8) for 24 weeks. Body weight was monitored from baseline to 24 weeks at 2 weeks intervals. After 24 weeks of treatment, plasma lipid variables were measured. Movat's staining and immunohistochemical staining were performed on frozen sections of the aortic roots to calculate VP percentage and intraplaque hemorrhage (IPH) percentage and detect expression of NPY, vascular endothelial growth factor (VEGF), and CD31. In vitro, the expressions of Y2R, VEGF, and CD31 were detected by immunofluorescence staining in aortic endothelial cells incubated with PBS, 100μM METH, 10nmol NPY, or 100μM METH plus 10nmol NPY for 12 hours. The CD31 positive area, percentage of IPH, VP, and the expressions of NPY and VEGF were significantly increased in the M8 group than in the NS group. In vitro, the expressions of Y2R, VEGF, and CD31 were significantly increased in the METH+NPY group than in the PBS, METH, and NPY groups and these effects could be blunted by treatment with a Y2R antagonist or DPPIV inhibitor. Chronic METH administration could aggravate VP in ApoE-/- mice fed with a high-cholesterol diet, possibly through upregulating vascular NPY and VEGF expression and promoting angiogenesis and vessel rupture in atherosclerotic plaques. Our findings indicated that increased VP formation might contribute to the development of acute coronary syndrome post-chronic METH abuse by activating DPPIV/NPY/Y2R pathway.

Scavenger receptor-AI targeted theranostic nanoparticles for regression of atherosclerotic plaques via ABCA1 modulation

ATP-binding cassette transporter A1 (ABCA1) plays a crucial role in atherosclerotic formation through mediated cholesterol efflux in macrophage-derived foam cells. In this study, a scavenger receptors AI (SR-AI) targeted theranostic nanoparticles was constructed for atherosclerosis regression via ABCA1 activation in foam cells. ABCA1-upregulator 5242331 and IR780 were encapsulated in PLGA-PEG micelles which were conjugated with SR-AI targeting peptide (PP1) to formulate the nanoparticles (SAU-NPs). Immunostaining revealed that SR-AI was highly expressed both in macrophage foam cells and in atherosclerotic plaque of ApoE−/− mice. The SAU-NPs have shown more active targeting to plaque lesion with higher stability compared with non-SR-AI targeted nanoparticles. The transformation from macrophage to foam cells was inhibited by SAU-NPs carried 5242331. Cholesterol deposition was effectively reduced in foam cells by SAU-NPs through activating the LXRα-ABCA1/ABCG1/SR-BI pathway. In conclusion, theranostic SAU-NPs which carried ABCA1-upregulator 5242331 exert beneficial effects on atherosclerosis regression via LXRα activation.

Defining the Potential Targets for Biological Activity of Isoegomaketone Based on Network Pharmacology and Molecular Docking Methods.

Isoegomaketone is a water-soluble natural ketone compound that is commonly present in Rabdosia angustifolia and Perilla frutescens. At present, it is known that isoegomaketone has a wide range of pharmacological activity, but there has been no thorough investigation of its potential targets. As a result, we examined the potential targets of isoegomaketone using the network pharmacology approach. In our study, the TCM Database@Taiwan was utilized to search for the chemical formula. The pharmacological characteristics of isoegomaketone were then evaluated in silico using the Swiss Absorption, Distribution, Metabolism, and Excretion (Swiss ADME) and Deep Learning-Acute Oral Toxicity (DL-AOT) methods, and the potential isoegomaketone target genes were identified using a literature study. Additionally, using the clusterProfiler R package 3.8.1, the Gene Ontology (GO) enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of target genes were performed. In order to obtain the protein interaction network, we simultaneously submitted the targets to the STRING database. After this, we performed molecular docking with respect to targets and isoegomaketone. Finally, we created visual networks of protein-protein interactions (PPI) and examined these networks. Our results showed that isoegomaketone had good drug-likeness, bioavailability, medicinal chemistry friendliness, and acceptable toxicity. Subsequently, through the literature analysis, 48 target genes were selected. The bioinformatics analysis and network analysis found that these target genes were closely related to the biological processes of isoegomaketone, such as atherosclerotic formation, inflammation, tumor formation, cytotoxicity, bacterial infection, virus infection, and parasite infection. These findings show that isoegomaketone may interact with a wide range of proteins and biochemical processes to form a systematic pharmacological network, which has good value for the creation and use of drugs.

Mathematical modeling and simulation of atherosclerotic formation and progress at arterial bifurcations

Atherosclerosis is a chronic inflammatory disease which is characterized by lipid deposits. Understanding the development of atherosclerosis plaque is of importance to the treatment of the disease. In this work, we develop a mathematical model for the formation and growth of atherosclerosis plaque, which includes the following key variables: low-density lipoprotein (LDL) and high-density lipoprotein (HDL), free radicals and oxidized LDL, and cells: macrophages (M), foam cells (F), endothelial cells and smooth muscle cells. The mass transports of LDL and HDL and their biochemical reactions through the endothelium are expressed by a coupled set of advection–diffusion-reaction equations with time-dependent porosity, and transport equations of dilute substance for the interfacial coupling at intima. A locally varying accumulation of the macrophages and foam cells at the arterial bifurcations with and without lesion is calculated using finite element method. The results suggest that inflammation and material accumulation are more likely to occur at the low shear stresses such as arterial bifurcations. The plaque growth decreases with the wall porosity. The average growth rate of plaque in the lesion is 1.3 times that in the healthy wall. Moreover, the plaque development in lesion may contribute to the plaque growth of the healthy wall. The model can help for understanding of the mechanisms in the formation of an early atherosclerotic plaque.

Abstract MP42: Macrophage Chromatin Remodeling Complex Subunit Baf60a In Atherosclerosis

Objectives: Atherosclerosis is a primary medical concern due to the increasing prevalence and lack of effective treatment that reverses the disease progression. While multiple genetic mutations/variations have been associated with atherosclerotic risk, the development of atherosclerosis in response to risk factors is also contributed by factors at the epigenetic and chromatin level. The SWI/SNF chromatin remodeling complex alters DNA accessibility and chromatin structure to modulate gene expression in response to external and internal cellular environments, potentially serving as an underexplored compartment of CVD and atherosclerosis development. Approach and Results: In an effort to identify key chromatin remodeling compartments involved in atherosclerotic foam cell formation, primary bone marrow-derived macrophages (BMDMs) were exposed to a pro-atherogenic environment, specifically to oxidized Low-density lipoprotein (oxLDL). We observed drastically and time-dependent decrease in the protein abundance of BAF60a, a transcription factor interacting subunit of the SWI/SNF chromatin remodeling complex. Macrophage-specific Baf60a deletion in ApoE deficient mice showed over 30% increase in aortic plaque formation after 16-weeks of western diet feeding (N=12, p=0.0097). Integrated analysis of RNA-seq and ATAC-seq regulatory network in oxLDL treated BAF60a deficient BMDMs identified a shift of chromatin accessibility, transcription factor footprint, and a reshape in gene expression patterns that regulate extracellular matrix organization, focal adhesion, integrin signaling, inflammation, and lead to foam cell formation which ultimately contribute to the atherosclerotic plaque build-up. Conclusions: Our data demonstrated the role of macrophage BAF60a in atherogenesis and suggested a potential therapeutic target to treat atherosclerosis, presumably by compensating for the loss of Baf60a.

TongGuanWan Protects Cardiac Hypertrophy through regulation of Apoptosis and Fibrosis

Cardiac hypertrophy is characterized by increased cardiomyocyte size including physiological and pathological hypertrophy. Doxorubicin (DOX) widely used as the most potent anthracycline antibiotic agents for a wide range of cancers. DOX is induce cardiac hypertrophy because of it has a dose-limiting side effect such as dilated cardiomyopathy and lipid peroxidation. TongGuanWan (TGW, 通關丸), a well-known traditional herbal formula, has been reported that delay atherosclerotic formation and development and improving diabetes. which is most closely related to diabetes mellitus. However, the protective effect of TGW on cardiac hypertrophy and fibrosis was not investigated. The aim of this study was to investigate the effects of TGW on cardiac hypertrophy and fibrosis, which has been implicated in heart failure in H9c2 cells and isoproterenol (ISO)-induced cardiac hypertrophy mice. In vitro, H9c2 cells were induced by DOX (1 μM) in the presence or absence of TGW (1–10 μg/ml) and incubated for 24 h. In vivo, TGW was administrated to ISO-induced cardiac hypertrophy mice (n=8) to 100 and 200 mg/kg/day concentrations, respectively. The experiment was measured for 2 weeks following TGW respectively. The results of in vitro study indicated that TGW inhibit the increase cell surface area and the upregulation of hypertrophy markers including atrial natriuretic peptide (ANP), B-type natriuretic peptide (BNP), beta-myosin heavy chain (β-MHC), and Myosin Light Chain-2 (MLC2) in H9c2 cells. In addition, TGW reduced DOX-induced the MAPKs protein expression and NF-κB p65 activation in H9c2 cells. TGW treatment remarkably inhibit activation of GATA-4/calcineurin/NFAT-3 signaling pathway under DOX conditions. Moreover, TGW significantly reduce DOX-induced expression of cell apoptosis-related proteins and fibrosis biomarkers. The results of in vivo study indicated that TGW significantly reduced the heart weight mass to body weight ratio (HW/BW) and left ventricle mass to body weight ratio (LV/BW) levels compared to the untreated the ISO-induced cardiac hypertrophy mice. Administration of TGW reduced protein expression of hypertrophy markers in cardiac hypertrophy mice. Moreover, TGW showed decreased that perivascular fibrosis and vessel hypertrophy in the heart tissues of cardiac hypertrophy mice, as determined by Picro-Sirius Red staining. TGW group significantly inhibited protein and mRNA expression levels of fibrosis related factors such as fibronectin, α-SMA and collagen type I compared to the untreated the ISO-induced cardiac hypertrophy group. Therefore, these results suggest that TGW may be potential therapies targeting the prevention and cure of cardiac hypertrophy and fibrosis, which finally causes sudden heart failure.

Influence of Intermittent Hypoxia/Hypercapnia on Atherosclerosis, Gut Microbiome, and Metabolome.

Obstructive sleep apnea (OSA), a common sleep disorder characterized by intermittent hypoxia and hypercapnia (IHC), increases atherosclerosis risk. However, the contribution of intermittent hypoxia (IH) or intermittent hypercapnia (IC) in promoting atherosclerosis remains unclear. Since gut microbiota and metabolites have been implicated in atherosclerosis, we examined whether IH or IC alters the microbiome and metabolome to induce a pro-atherosclerotic state. Apolipoprotein E deficient mice (ApoE−/−), treated with IH or IC on a high-fat diet (HFD) for 10 weeks, were compared to Air controls. Atherosclerotic lesions were examined, gut microbiome was profiled using 16S rRNA gene amplicon sequencing and metabolome was assessed by untargeted mass spectrometry. In the aorta, IC-induced atherosclerosis was significantly greater than IH and Air controls (aorta, IC 11.1 ± 0.7% vs. IH 7.6 ± 0.4%, p < 0.05 vs. Air 8.1 ± 0.8%, p < 0.05). In the pulmonary artery (PA), however, IH, IC, and Air were significantly different from each other in atherosclerotic formation with the largest lesion observed under IH (PA, IH 40.9 ± 2.0% vs. IC 20.1 ± 2.6% vs. Air 12.2 ± 1.5%, p < 0.05). The most differentially abundant microbial families (p < 0.001) were Peptostreptococcaceae, Ruminococcaceae, and Erysipelotrichaceae. The most differentially abundant metabolites (p < 0.001) were tauro-β-muricholic acid, ursodeoxycholic acid, and lysophosphoethanolamine (18:0). We conclude that IH and IC (a) modulate atherosclerosis progression differently in distinct vascular beds with IC, unlike IH, facilitating atherosclerosis in both aorta and PA and (b) promote an atherosclerotic luminal gut environment that is more evident in IH than IC. We speculate that the resulting changes in the gut metabolome and microbiome interact differently with distinct vascular beds.

MiR-520b inhibits endothelial activation by targeting NF-κB p65-VCAM1 axis

MiR-520b belongs to the miR-373/520 family, is expressed only in human and nonhuman primates. Previous reports indicated that the expression of miR-520b was repressed in human atherosclerotic plaque tissue compared with healthy vessels. However, the role of miR-520b in coronary artery disease still remains to be uncovered. In this study, we demonstrated that endothelial cells (ECs) in human atherosclerotic plaques expressed miR-520b and aimed to elucidate the impact of miR-520b on EC activation and inflammatory response. To determine the potential targets of miR-520b, we performed RNA-seq analysis by transfecting miR-520b mimics in ECs. The quantitative real-time PCR (qPCR) validation suggested that miR-520b over-expression reduced pro-inflammatory gene expression (e.g. ICAM1, VCAM1, SELE) while the inhibition of miR-520b induced their expression. By combining bioinformatics prediction and functional assays, we identified that RELA (Nuclear Factor-κB (NF-κB) Transcription Factor P65) was a direct target of miR-520b. Moreover, miR-520b mimics attenuated monocyte adhesion and monocyte trans-endothelial migration (the initial steps of atherosclerotic formation) in response to lipopolysaccharides (LPS) stimulation. Re-expression of a non-miR-targetable version of p65 could rescue the reduced monocyte cell attachment, suggesting that this process is NF-κB p65 dependent. MiR-520b reduced the abundance of NF-κB p65 in cytoplasmic fractions without corresponding increase in nuclear fractions, indicating that this regulation is independent of p65 translocation process. MiR-520b mimics attenuated the activity of VCAM-1 promoter, whereas miR-520b inhibitor activated its activity. However, miR-520b inhibitor had no effect on promoter activity containing the mutated NF-κB p65 binding sites, strongly demonstrating that the impact of miR-520b on VCAM1 gene is mediated by NF-κB p65.Thus, we concluded that miR-520b suppressed EC inflammation and the cross-talk between monocytes and ECs by down-regulating NF-κB p65-ICAM1/VCAM1 axis and might serve as a potential therapeutic target for EC dysfunction and atherosclerosis.

Prevalence, clinical characteristics and prognosis of intracranial artery atherosclerosis in heterozygous familial hypercholesterolemia: insights from magnetic resonance angiography imaging analysis

Abstract Introduction Heterozygous familial hypercholesterolemia (HeFH) exhibits substantially atherogenic substrate which involves coronary and peripheral arteries. Whether atherosclerosis in HeFH propagates to intracranial arteries causing stroke remains to be determined. Purpose To characterize intracranial artery stenosis (IAS) in subjects with HeFH. Methods 148 HeFH subjects who underwent MRI/MRA imaging to evaluate intracranial arteries were analyzed. IAS was defined as the presence of stenosis with its % diameter stenosis ≥25%. Clinical demographics and cardiovascular events (all-cause death, ACS, stroke and PAD) were compared in those with and without IAS. Results IAS was observed in 24.3% (=36/148) of study subjects. It was more frequently located at middle cerebral artery (30.6%=11/36), followed by internal carotid artery (25.0%=9/36). 47.2% of IAS exhibited % diameter stenosis ≥75%. Furthermore, 58.3% of HeFH patients with IAS exhibited concomitance of CAD, PAD or carotid stenosis. They were more likely to be older (Table). While there was no significant difference in LDL-C level, an elevated triglyceride level was observed in those with IAS (Table). Of note, during the observational period (median=14.1 years), IAS was associated with a greater likelihood of experiencing not only stroke but other cardiovascular events (all-cause death + ACS + PAD) (picture). Multivariate analysis demonstrated triglyceride level ≥1.7mmol/l as an independent predictor of IAS in HeFH patients (HR=5.53, 95% CI: 1.85–16.5, p=0.002). Conclusions Around one-fourth of HeFH patients harboured IAS, which was associated with concomitance of atherosclerosis in other vascular beds and the occurrence of stroke and other cardiovascular events. Given the relationship of IAS with hypertriglyceridemia, this lipid feature may be an important contributor to atherosclerotic formation which involves intracranial artery in HeFH patients. Clinical outcome Funding Acknowledgement Type of funding source: None

BFGF blockade reduces intraplaque angiogenesis and macrophage infiltration in atherosclerotic vein graft lesions in ApoE3*Leiden mice

Intraplaque angiogenesis increases the chance of unstable atherosclerotic plaque rupture and thrombus formation leading to myocardial infarction. Basic Fibroblast Growth Factor (bFGF) plays a key role in angiogenesis and inflammation and is involved in the pathogenesis of atherosclerosis. Therefore, we aim to test K5, a small molecule bFGF-inhibitor, on remodelling of accelerated atherosclerotic vein grafts lesions in ApoE3*Leiden mice. K5-mediated bFGF-signalling blockade strongly decreased intraplaque angiogenesis and intraplaque hemorrhage. Moreover, it reduced macrophage infiltration in the lesions by modulating CCL2 and VCAM1 expression. Therefore, K5 increases plaque stability. To study the isolated effect of K5 on angiogenesis and SMCs-mediated intimal hyperplasia formation, we used an in vivo Matrigel-plug mouse model that reveals the effects on in vivo angiogenesis and femoral artery cuff model to exclusively looks at SMCs. K5 drastically reduced in vivo angiogenesis in the matrigel plug model while no effect on SMCs migration nor proliferation could be seen in the femoral artery cuff model. Moreover, in vitro K5 impaired endothelial cells functions, decreasing migration, proliferation and tube formation. Our data show that K5-mediated bFGF signalling blockade in hypercholesterolemic ApoE3*Leiden mice reduces intraplaque angiogenesis, haemorrhage and inflammation. Therefore, K5 is a promising candidate to stabilize advanced atherosclerotic plaques.

MicroRNA predicts cognitive performance in healthy older adults

The expression of microRNA (miRNA) is influenced by ongoing biological processes, including aging, and has begun to play a role in the measurement of neurodegenerative processes in central nervous system. The purpose of this study is to utilize machine learning approaches to determine whether miRNA can be utilized as a blood-based biomarker of cognitive aging. A random forest regression combining miRNA with biological (brain volume), clinical (comorbid conditions), and demographic variables in 115 typically aging older adults explained the greatest level of variance in cognitive performance compared to the other machine learning models explored. Three miRNA (miR-140-5p, miR-197-3p, and miR-501-3p) were top-ranked predictors of multiple cognitive outcomes (Fluid, Crystallized, and Overall Cognition) and past studies of these miRNA link them to cellular senescence, inflammatory signals for atherosclerotic formation, and potential development of neurodegenerative disorders (e.g., Alzheimer’s disease). Several novel miRNAs were also linked to age and multiple cognitive functions, findings which together warrant further exploration linking these miRNAs to brain-derived metrics of neurodegeneration in typically aging older adults.

Association between serum uric acid level and endothelial dysfunction in elderly individuals with untreated mild hypertension.

BackgroundEndothelial dysfunction is the initial stage in atherosclerotic formation and progression and is associated with high serum uric acid (SUA) level. We hypothesized that reactive hyperemia index (RHI), which reflects endothelial function, is associated with SUA levels in elderly individuals with untreated mild hypertension.MethodsWe recruited 123 patients ≥ 60 years with untreated mild hypertension. The association between SUA level and RHI was analyzed using univariate correlation analysis and multiple regression analysis. The receiver operating characteristic (ROC) curve was performed to validate the cutoff value of SUA that can be used to predict endothelial dysfunction.ResultsThe serum uric acid level significantly increased in the RHI < 1.67 group, and this result was still observed in the subgroup of men. RHI was inversely associated with SUA level (P = 0.006) and the association was still observed after adjusting for factors, such as age, sex, smoking status, and creatinine level (P = 0.014). In the subgroup analysis, a positive association was observed only in men. In the ROC curve analysis, the optimal cutoff values of SUA for predicting endothelial dysfunction was 293.5 µmol/L in elderly mild hypertension patients and 287.0 µmol/L in men.ConclusionA high SUA level was considered an independent predictor of endothelial dysfunction among elderly individuals, particularly men with untreated mild hypertension.

Electronegative low-density lipoprotein of patients with metabolic syndrome induces pathogenesis of aorta through disruption of the stimulated by retinoic acid6 cascade.

Aims/IntroductionElectronegative low‐density lipoprotein (L5) is the most atherogenic fraction of low‐density lipoprotein and is elevated in people with metabolic syndrome (MetS), whereas the retinol‐binding protein 4 receptor (stimulated by retinoic acid 6 [STRA6]) cascade is disrupted in various organs of patients with obesity‐related diseases. Our objective was to investigate whether L5 from MetS patients capably induces pathogenesis of aorta through disrupting the STRA6 cascade.Material and MethodsWe examined the in vivo and in vitro effects of L5 on the STRA6 cascade and aortic atherogenic markers. To investigate the role of this cascade on atherosclerotic formation, crbp1 transfection was carried out in vitro.ResultsThis study shows that L5 activates atherogenic markers (p38 mitogen‐activated protein kinases, pSmad2 and matrix metallopeptidase 9) and simultaneously suppresses STRA6 signals (STRA6, cellular retinol‐binding protein 1, lecithin‐retinol acyltransferase, retinoic acid receptor‐α and retinoid X receptor‐α) in aortas of L5‐injected mice and L5‐treated human aortic endothelial cell lines and human aortic smooth muscle cell lines. These L5‐induced changes of the STRA6 cascade and atherogenic markers were reversed in aortas of LOX1−/− mice and in LOX1 ribonucleic acid‐silenced human aortic endothelial cell lines and human aortic smooth muscle cell lines. Furthermore, crbp1 gene transfection reversed the disruption of the STRA6 cascade, the phosphorylation of p38 mitogen‐activated protein kinases and Smad2, and the elevation of matrix metallopeptidase 9 in L5‐treated human aortic endothelial cell lines.ConclusionsThis study shows that L5 from MetS patients induces atherogenic markers by disrupting STRA6 signaling. Suppression of STRA6 might be one novel pathogenesis of aorta in patients with MetS.

107Diagnostic accuracy of optical coherence tomography for the identification of in-stent fibroatheroma following stent implantation: an ex-vivo histological validation study

Abstract Background Previous histopathological studies have demonstrated that new atherosclerotic formation within the neointima, called neoatherosclerosis, is one of the most important mechanisms leading to both very late in-stent restenosis and stent thrombosis after stent implantation. Therefore, to distinguish lipid-containing atherosclerotic neointima from other tissues using intracoronary imaging modalities is clinically important to prevent late stent failures. Purpose This study evaluated the diagnostic performance of optical coherence tomography (OCT) for the detection of “in-stent fibroatheroma” following stent implantation by comparing cross-sections of the model with the corresponding histological images. Methods Fifty stented coronary arteries from the 31 autopsy hearts were imaged by OCT. Coronary arterial histopathological specimens, all of which included more than 30% of %neointimal hyperplasia, were compared with the corresponding OCT cross-sections. Histological in-stent fibroatheroma was defined as neointima containing large necrotic core and inflammatory cells. OCT-derived in-stent fibroatheroma comprised a low-intensity tissue containing a poorly delineated region with invisible stent strut behind low signal intensity. Results A total of 122 OCT cross-sections were compared with histological images. OCT examination revealed that 24 images (20%) contained low-intensity tissue inside the neointima. Of those, 5 images, in which stent strut behind low signal intensity was invisible, were diagnosed as OCT-derived in-stent fibroatheroma (4%) (Figure A). By histological analysis, only 4 images were classified as in-stent fibroatheroma (3%) (Figure B). With histology as the gold standard, the sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy for OCT-derived in-stent fibroatheroma were 100%, 99%, 80%, 100%, and 99%, respectively. The only histological finding underlying the false-positive-diagnosis of OCT-derived in-stent fibroatheroma was foam cells accumulation without necrotic core on the neointimal surface (Figure C and D). Most tissue that showed low-intensity tissue with visible stent strut by OCT contained proteoglycan matrix and organized thrombus in the absence of an underlying necrotic core. Coregistration of OCT with histology Conclusion This study showed the potential capability of OCT based on the visualization of stent struts behind low-intensity regions for discriminating in-stent fibroatheroma from other neointimal tissues following stent implantation.

Different Impacts of Intermittent Hypoxia and Hypercapnia on Atherosclerotic Formation

Obstructive sleep apnea (OSA) is a common disorder characterized by intermittent hypoxia and hypercapnia (IHC) during sleep and has been considered a risk for atherosclerosis. However, the particular role of intermittent hypoxia (IH), intermittent hypercapnia (IC) or their combination (IHC) in inducing or promoting atherosclerosis remains obscure. To dissect the mechanisms involved, we examined atherosclerotic formation in the Aorta, Aortic arch and Pulmonary artery (PA) in pro‐atherogenesis mouse model apolipoprotein E (ApoE) deficient mice, after IHC, IH, or IC exposure on high fat diet (HFD) as compared to room air (RA) groups either under HFD or regular chow (RC). Our data revealed that all HFD‐treated mice exhibited more atherosclerotic lesions than those fed with RC (e.g. Aorta, RA‐HFD 8.1±0.8% vs RA‐RC 1.0±0.3%, p&lt;0.01). 10‐week IHC treatment expedited atherosclerosis in Aorta, Aortic arch and PA as compared to room air controls in the presence of HFD (Aorta, IHC‐HFD 13.8±1.0% vs RA‐HFD 8.1±0.8%, p&lt;0.01; Aortic arch, IHC‐HFD 28.5±1.9% vs RA‐HFD 16.6±2.0%, p&lt;0.01; PA, IHC‐HFD 28.9±2.8% vs RA‐HFD 12.2±1.5%, p&lt;0.01). Furthermore, IHC‐induced atherosclerosis in Aorta was significantly greater than in IC or IH (Aorta, IHC‐HFD 13.8±1.0% vs either IH‐HFD 7.6±0.4%, p&lt;0.01 or IC‐HFD 11.1±0.7%, p&lt;0.05), indicating that the effect of IHC is the result of potential interactions between IC and IH. Interestingly, in the PA, the largest atherosclerotic formation was observed in IH‐treated mice, followed by IHC then IC (PA, IH‐HFD 40.9±2.0% vs either IHC‐HFD 28.9±2.8%, p&lt;0.01 or IC‐HFD 20.1±2.6%, p&lt;0.01), suggesting that (a) IH has a greater effect on the PA than on the Aorta and (b) IC may alleviate IH‐ or IHC‐induced lesion in the PA. Our findings suggest that (1) IH, IC and IHC affect the development of atherosclerosis differently and (2) distinct vasculatures (Aorta and Pulmonary artery) react to IHC, IH, IC differently in atherogenesis.Support or Funding InformationSupported by the National Institutes of Health grant 5 P01 32573 (G.G.H.)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Decompensation of PEDF Accelerates Atherosclerosis Development via Promoting VEGFB-FATP3/4-Dependent Endothelial FA Uptake in Mice with Hyperlipidemia

Background: Pigment epithelial-derived factor (PEDF) is protectively involved in atherosclerosis induced by hyperlipidemia, but expression characteristics of PEDF and the role of PEDF in the later stage of progressive atherosclerosis remain unclear. Methods: Circulating PEDF were analyzed in patients with atherosclerotic cardiovascular disease (ASCVD) and in murine models of wildtype (WT) mice and ApoE-/- mice under long-term high-fat diet (HFD). PEDF-/-/ ApoE-/- mice and matching PEDF+/+/ ApoE-/- mice fed with HFD for 24, 36 and 48 weeks, combined with injections of adeno-associated virus encoding PEDF (AAV-PEDF) in ApoE-/-/PEDF-/- mice were used to investigate the effects of PEDF knockdown on vascular function and structure. Experiments in vitro and in vivo were applied to identify PEDF regulate vascular endothelial growth factor (VEGFB) signaling pathway mediated endothelial fatty acid (FA) uptake. Findings: Circulating PEDF was increased in ASCVD patients compared to normal individuals, while decreasing trends were confirmed in murine models of WT mice and ApoE-/- mice on long-term HFD. ApoE-/-/PEDF-/- mice placed on HFD were fatter and had accelerated atherosclerotic formation, as evidenced by higher serum lipid levels, increased atherosclerotic plaques, pronounced vascular dysfunction and increased lipid accumulation in peripheral tissues, whereas injections of AAV-PEDF in ApoE-/-/PEDF-/- mice significantly improved. Mechanistically, PEDF deletion activated VEGFB paracrine signaling by upregulating expressions of VEGFB in peripheral tissues and its downstream targets on endothelial cells, including its receptors, namely VEGFR1 and neuropilin-1, and fatty acid transport protein 3 and 4 to enhance FA uptake. Interpretation: Decreasing expression of PEDF may decompensate to aggravate atherosclerosis. Funding: National Nature Science Foundation of China, Science and Technology Project of Guangzhou. Declaration of Interest: The authors declare no conflict of interest. Ethical Approval: The study was approved by the ethical committees of Sun Yat-sen Memorial Hospital and Sun Yat-sen University.

Abstract WP494: Stroke Risk and Symptom Recognition Post Cardiac Catheterization

Over 1.4 million cardiac catheterization procedures(CCPs) take place yearly. CCP related stroke incidence in 1973 was reported as 0.23%. CCPs are invasive in nature; complications occurring due to unintentional trauma to atherosclerotic aortic plaques or thrombus formation on catheters/guidewires. With improved practice, current incidence is 0.06%. Performing &gt;4000 procedures in FY2017, our facility sought to compare our statistics vs. current literature. Cardiovascular disease was the leading cause of global death in 2013 (17.3 million); stroke at 11.8 million. Ninety-two million Americans live with cardiovascular disease/stroke after effects accruing $316 billion in indirect costs. Seventeen percent of strokes occur in hospital; with stroke suffered post CCPs having morbidity/mortality rates 19-37%. Time to recognition/treatment of stroke symptoms is vital for best outcomes. Increase in visual symptoms post CCPs was noted with questionable correlation to radial access. Staff education on atypical stroke symptom recognition/empowerment and comfort to initiate Code Strokes was conducted. There was variability in practitioner approach to calling Code Strokes vs. observing patients post symptom recognition. Meetings held with Cardiology, Neurology, Hospital Administration, Departmental Leadership, Stroke Manager came to consensus on patient management. There should be low threshold for performing screening neurological exams and calling Code Strokes. With more sensitive diagnostic tools, diagnosis should be streamlined. Code Stroke data was collected December 2015-November 2017. Data analysis showed 48 Code Strokes called; 30 confirmed (67% male, 63% radial, 57% interventional procedures). Presenting symptoms, in order of frequency, were: vision, arm drift/weakness, facial droop, speech. The typical FAST stroke assessment would not be helpful in majority of these patients, however, education to atypical symptoms was beneficial. Literature shows women have higher stroke risk after CCPs. Our analysis showed higher prevalence in men with radial access. The most common symptom of visual changes, results in NIHSS of 0, which may impact practitioners ordering stroke work-ups; when focus should be patient disability.

Abstract 16725: A Novel Role for MAGI1 in Disturbed Flow-Induced Endoplasmic Reticulum Stress in Endothelial Cells

Introduction: Atherosclerotic plaque predominantly develops in areas where endothelial cells (ECs) are exposed to disturbed flow (d-flow). Endoplasmic reticulum (ER) stress, characterized by the activation of ER transmembrane sensor ATF6 and transcription factor XBP-1, has been implicated in d-flow-induced atherogenesis. At d-flow regions, expression of both total and spliced XBP-1 and activation of ATF6 are increased, resulting in EC apoptosis. Additionally, over-expression of XBP-1 accelerates atherosclerotic formation. A recent genome-wide association study revealed a strong correlation between membrane-associated guanylate kinase with inverted domain structure-1 (MAGI1), a scaffold protein that associates with the tight and adherens junctions, and chronic inflammatory diseases. Hypothesis: We hypothesize that MAGI1 is crucial in d-flow-induced EC inflammation, apoptosis, and atherogenesis via regulating ER stress signaling. Methods and Results: Microarray analysis revealed that MAGI1 depletion inhibits ER-stress related genes, including XBP-1. qRT-PCR results confirmed that MAGI1 depletion abolished d-flow-mediated expression of spliced and full-length XBP-1 which correlated with reduced d-flow-induced apoptosis. To examine the mechanism by which MAGI1 regulates ER stress signaling, we found that MAGI1 is associated with ATF6, and that MAGI1-ATF6 complex formation is increased by inflammatory stimuli including d-flow and thrombin. Because the cleaved form of ATF6 can translocate from ER and Golgi to the nucleus, where it binds to ER-stress response elements and upregulates XBP-1 expression, we asked if MAGI1 facilitates ATF6 nuclear translocation. We found that thrombin-mediated ATF6 nuclear translation is significantly inhibited by MAGI1 depletion. Conclusions: Our results indicate that d-flow elicits the formation and translocation of a MAGI1-ATF6 complex from the cytosol to the nucleus that leads to ER stress via XBP1 induction and EC apoptosis. Our study suggests a novel role for endothelial MAGI1 as a link between d-flow and ER stress, both of which are fundamental constituents of atherogenesis.

Simultaneous inhibition of FXR and TGR5 exacerbates atherosclerotic formation

Simultaneous activation of bile acid receptors farnesoid X receptor (FXR) and G protein-coupled bile acid receptor 1 (TGR5) by INT-767 significantly reduces atherosclerotic formation. In this study, we investigated the effect of simultaneous inactivation of these bile acid receptors in atherosclerosis and which bile acid receptor mediates the anti-atherogenic effect of INT-767. To investigate the role of simultaneous inactivation of FXR and TGR5 in vivo, we generated LDL receptor knockout (LDLR) KO mice with FXR and TGR5 dual deficiency, which exhibited severe atherosclerosis and aortic inflammation through nuclear factor κΒ activation. The lipid-lowering effects of INT-767 were completely blocked by FXR single deficiency but not TGR5 single deficiency. INT-767 was able to block atherosclerotic formation and decrease levels of aortic cytokines and chemokines in LDLR KO mice under either FXR or TGR5 single deficiency. Dual deficiency of FXR and TGR5 completely blocked the anti-atherogenic and anti-inflammatory effects of INT-767 in LDLR KO mice. We demonstrated that 1) FXR and TGR5 dual deficiency exacerbated the development of atherosclerosis and 2) the anti-atherogenic effect of INT-767 requires the anti-inflammatory effect but not the lipid-lowering effect through the simultaneous activation of FXR and TGR5. Our results indicate that dual activation of FXR and TGR5 is a promising strategy for treating atherosclerosis.

Abstract 205: Stroke Risk and Symptom Recognition Post Cardiac Catheterization

Over 1.4 million cardiac catheterization procedures (CCPs) take place yearly. CPP related stroke incidence in 1973 was reported as 0.23%. CCPs are invasive in nature with complications occurring due to unintentional trauma to preexisting atherosclerotic aortic plaques or thrombus formation at catheter/guidewire tips. Less common causes of ischemic stroke are air, left ventricular clot, hypotension, arterial dissection, fractured guidewire. Transient neurological deficits have been reported following high-osmolar contrast injection into carotid/vertebral arteries. With improved practice, current stroke incidence is 0.06%. Performing &gt;4000 procedures in FY 2017, our facility sought to compare our statistics vs. current literature. Cardiovascular disease was the leading cause of global death in 2013 (17.3 million); stroke close behind at 11.8 million. Ninety-two million Americans live with cardiovascular disease/stroke after effects accruing $316 billion in indirect costs: health expenditures/lost productivity. Seventeen percent of strokes occur in the hospital; with stroke suffered post CCPs having morbidity/mortality rates of 19-37%.Time to recognition/treatment of stroke symptoms is vital to provide best outcomes. Increase in visual symptoms post CCPs was noted by Procedural Care Unit staff with questionable correlation to radial access usage. Staff education on atypical stroke symptom recognition/empowerment and comfort to initiate Code Stroke protocol was conducted. There was variability in practitioner approach to calling Code Strokes vs. observing patients post symptom recognition. Meetings were held with Cardiology, Neurology, Hospital Administration, Departmental Leadership, Stroke Manager to come to consensus on patient management. There should be a low threshold for performing screening neurologic exams: alertness, speech, visual, sensory, motor symptoms and for calling Code Strokes. With more sensitive diagnostic tools, the process of diagnosis should be streamlined. Real time Code Stroke data was collected from December 2015-November 2017;with final analysis completed in November 2017.The research team consisted of PCU Clinical Manager, PCU Clinical Lead, Stroke Manager. Data analysis showed 48 Code Strokes called; 30 being confirmed as strokes. Of confirmed cases 67% were male, 63% were radial, 57% had interventional procedures. Presenting symptoms of stroke, in order of frequency, were vision, arm drift/weakness, then facial droop and speech. The typical act FAST stroke assessment tool would not be helpful in the majority of these patients. Literature shows women have higher stroke risk after CCPs. Our analysis showed higher prevalence in men and with radial access. The most common symptom of visual changes, results in NIHSS scores of 0, which may impact practitioners ordering stroke work-ups; when focus should be on patient disability.