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Background and Aims: Ticagrelor reduces cardiovascular events in patients with acute coronary syndrome (ACS). Recent studies demonstrated the expression of P2Y12 on vascular cells including endothelial cells, as well as platelets, and suggested its contribution to atherogenesis. We investigated whether ticagrelor attenuates vascular dysfunction and inhibits atherogenesis in apolipoprotein E-deficient (apoe -/- ) mice., Methods: Eight-week-old male apoe -/- mice were fed a western-type diet (WTD) supplemented with 0.1% ticagrelor (approximately 120 mg/kg/day). Non-treated animals on WTD served as control. Atherosclerotic lesions were examined by en-face Sudan IV staining, histological analyses, quantitative RT-PCR analysis, and western blotting. Endothelial function was analyzed by acetylcholine-dependent vasodilation using aortic rings. Human umbilical vein endothelial cells (HUVEC) were used for in vitro experiments., Results: Ticagrelor treatment for 20 weeks attenuated atherosclerotic lesion progression in the aortic arch compared with control (p < 0.05). Ticagrelor administration for 8 weeks attenuated endothelial dysfunction (p < 0.01). Ticagrelor reduced the expression of inflammatory molecules such as vascular cell adhesion molecule-1, macrophage accumulation, and lipid deposition. Ticagrelor decreased the phosphorylation of JNK in the aorta compared with control (p < 0.05). Ticagrelor and a JNK inhibitor ameliorated impairment of endothelium-dependent vasodilation by adenosine diphosphate (ADP) in wild-type mouse aortic segments. Furthermore, ticagrelor inhibited the expression of inflammatory molecules which were promoted by ADP in HUVEC (p < 0.001). Ticagrelor also inhibited ADP-induced JNK activation in HUVEC (p < 0.05)., Conclusions: Ticagrelor attenuated vascular dysfunction and atherogenesis through the inhibition of inflammatory activation of endothelial cells. These effects might be a potential mechanism by which ticagrelor decreases cardiovascular events in patients with ACS., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background and Aims: Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are major components of n-3 polyunsaturated fatty acids (n-3 PUFAs) which inhibit atherogenesis, although few studies have examined the effects of the combination of EPA and DHA on atherogenesis. The aim of this study was to investigate whether DHA has additional anti-atherosclerotic effects when combined with EPA., Methods: Male 8-week-old apolipoprotein E-deficient (Apoe -/- ) mice were fed a western-type diet supplemented with different amounts of EPA and DHA; EPA (2.5%, w/w), low-dose EPA + DHA (2.5%, w/w), or high-dose EPA + DHA (5%, w/w) for 20 weeks. The control group was fed a western-type diet containing no n-3 PUFA. Histological and gene expression analysis were performed in atherosclerotic lesions in the aorta. To address the mechanisms, RAW264.7 cells were used., Results: All n-3 PUFA treatments significantly attenuated the development and destabilization of atherosclerotic plaques compared with the control. The anti-atherosclerotic effects were enhanced in the high-dose EPA + DHA group (p < 0.001), whereas the pure EPA group and low-dose EPA + DHA group showed similar results. EPA and DHA additively attenuated the expression of inflammatory molecules in RAW264.7 cells stimulated with LPS. DHA or EPA + DHA suppressed LPS-induced toll-like receptor 4 (TLR4) expression in lipid rafts on RAW264.7 cells (p < 0.05). Lipid raft disruption by methyl-β-cyclodextrin suppressed mRNA expression of inflammatory molecules in LPS-stimulated macrophages., Conclusion: n-3 PUFAs suppressed atherogenesis. DHA combined with EPA had additional anti-inflammatory effects and inhibited atherogenesis in Apoe -/- mice. The reduction of TLR4 expression in lipid rafts in macrophages by DHA might be involved in this mechanism, at least partially., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Vector flow mapping (VFM) is a novel echocardiographic technology which enables visualization of the intraventricular flow velocity vector. Dissipative energy loss (EL) derived from the velocity vector field of intraventricular blood flow is considered to reflect the efficiency of blood flow, and could be an indicator of left ventricular function. We aimed to determine the reference values of the EL derived from VFM within the left ventricle., Methods: VFM analysis was performed using echocardiography in 64 healthy children. The velocity vector fields of the intra-left ventricular blood flow were obtained from the apical 5-chamber view, and the EL values during systole and diastole were calculated. The measurements were averaged over three cardiac cycles, and indexed to body surface area (BSA)., Results: The mean subject age was 6.8±4.3 years. The mean EL was 4.10±2.35mW/m/m(2) BSA during systole and 16.24±11.63mW/m/m(2) BSA during diastole. On multivariate analysis, age and heart rate (HR) were independent predictors of systolic EL, whereas age, HR, and E wave peak velocity were independent predictors of diastolic EL. The regression equations used to predict the BSA-indexed systolic and diastolic EL were as follows: log10 (systolic EL)=-0.0332-0.00213×age (months)+0.00789×HR (beats/min) (adjusted R(2), 0.833; p<0.0001); and log10 (diastolic EL)=0.277-0.00346×age (months)+0.00570×HR (beats/min)+0.00564×E wave peak velocity (cm/s) (adjusted R(2), 0.867; p<0.0001)., Conclusions: The systolic and diastolic EL were positively correlated with HR and negatively correlated with age. Moreover, the diastolic EL was positively correlated with the E wave peak velocity. The present study provides reference values for the systolic and diastolic EL that can be used in future studies examining patients with heart disease., (Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Objective: Activated factor X (FXa) plays a key role in the coagulation cascade, whereas accumulating evidence suggests that it also contributes to the pathophysiology of chronic inflammation on the vasculature. In this study, we assessed the hypothesis that rivaroxaban (Riv), a direct FXa inhibitor, inhibits atherogenesis by reducing macrophage activation., Methods and Results: Expression levels of PAR-1 and PAR-2, receptors for FXa, increased in the aorta of apolipoprotein E-deficient (ApoE(-/-)) mice compared with wild-type mice (P < 0.01, P < 0.05, respectively). Administration of Riv (5 mg/kg/day) for 20 weeks to 8-week-old ApoE(-/-) mice reduced atherosclerotic lesion progression in the aortic arch as determined by en-face Sudan IV staining compared with the non-treated group (P < 0.05) without alteration of plasma lipid levels and blood pressure. Histological analyses demonstrated that Riv significantly decreased lipid deposition, collagen loss, macrophage accumulation and matrix metallopeptidase-9 (MMP-9) expression in atherosclerotic plaques in the aortic root. Quantitative RT-PCR analyses using abdominal aorta revealed that Riv significantly reduced mRNA expression of inflammatory molecules, such as MMP-9, tumor necrosis factor-α (TNF-α). In vitro experiments using mouse peritoneal macrophages or murine macrophage cell line RAW264.7 demonstrated that FXa increased mRNA expression of inflammatory molecules (e.g., interleukin (IL)-1β and TNF-α), which was blocked in the presence of Riv., Conclusions: Riv attenuates atherosclerotic plaque progression and destabilization in ApoE(-/-) mice, at least in part by inhibiting pro-inflammatory activation of macrophages. These results indicate that Riv may be particularly beneficial for the management of atherosclerotic diseases, in addition to its antithrombotic activity., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Objective: Endogenous ligands such as high-mobility group box 1 (HMGB1) and nucleic acids are released by dying cells and bind to Toll-like receptors (TLRs). As TLR9 is involved in both microbial and sterile inflammation by detecting both bacterial and endogenous DNA, we investigated its role in inflammation and lesion formation in a mouse model of vascular injury., Methods and Results: C57BL/6 (WT) and TLR9 KO mice were subjected to wire-mediated vascular injury. Anti-HMGB1 antibody and purified HMGB1 protein were chronically delivered around the injured arteries by gelatin hydrogel, and neointima formation at 4 weeks after injury was evaluated. In addition, the same vascular injury was performed in bone-marrow chimeric mice (WT bone marrow into TLR KO mice; TLR9 KO bone marrow into WT mice). We also evaluated the production of inflammatory cytokines by mouse macrophages in response to HMGB1 and CpG-ODN. In wild-type mice after vascular injury, anti-HMGB1 antibody significantly reduced neointima formation and HMGB1 protein accelerated neointima hyperplasia. HMGB1 failed to accelerate lesion formation in TLR9 KO mice. The bone marrow transplantation study revealed that TLR9 in bone marrow-derived cells played a fundamental role in neointima formation. In vitro, HMGB1 and CpG-ODN synergistically induced the production of inflammatory cytokines by macrophages., Conclusions: HMGB1 serves as an endogenous mediator of inflammation and lesion formation via the TLR9 pathway in response to vascular injury. Blockade of HMGB1 and/or TLR9 may represent a novel approach to treating atherosclerosis., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Background: Inflammation is a critical contributing factor to the development and progression of atherosclerosis. Pentraxin 3 (PTX3) is produced abundantly in atherosclerotic lesions while C-reactive protein (CRP) is mainly produced in the liver. In this study, we investigated whether plasma levels of PTX3 might be a sensitive marker both for the severity of coronary artery disease and vulnerable plaques. Next, we determined whether assays for inflammatory molecules can be used to monitor the therapeutic effects of telmisartan on stabilization of vulnerable atherosclerotic plaques., Methods and Results: We measured PTX3 concentrations in the peripheral and coronary sinus plasma of 40 patients with angina pectoris (AP) and 20 control subjects. Next, in 28 patients with AP, we determined the correlation between levels of inflammatory molecules and the computed tomography (CT) density of plaques as a quantitative index of plaque vulnerability. There was no significant difference in peripheral plasma PTX3 concentrations between patients with AP and control subjects, while coronary sinus plasma PTX3 concentrations were significantly higher in AP patients than control subjects. The concentrations of PTX3 in coronary sinus and peripheral plasma correlated with Gensini scores as an index of severity of coronary atherosclerosis. Interestingly, there was a significantly negative correlation between plasma PTX3 concentrations and CT density (r=-0.67, p<0.01). On the other hand, CT density did not correlate with the peripheral plasma concentrations of monocyte chemoattractant protein-1 (MCP-1) or high-sensitivity CRP (hsCRP). Furthermore, telmisartan treatment for 6 months decreased plasma concentrations of PTX3 but not those of MCP-1 or hsCRP in 12 patients with essential hypertension. Multivariate regression analysis revealed that changes in PTX3 levels were independent of blood pressure changes., Conclusions: PTX3 is likely more specific than hsCRP as an indicator of coronary plaque vulnerability that could lead to plaque rupture., (Copyright © 2011 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: Dehydroepiandrosterone sulfate (DHEAS) is thought to be associated with life expectancy and anti-aging. However, its biological significance in atherosclerosis remains controversial. Therefore, the aim of this study was to determine whether DHEAS is associated with development of carotid atherosclerosis in subjects with cardiovascular risk factors., Subjects and Methods: A total of 419 Japanese individuals (208 males and 211 females) were recruited from Tokushima University Hospital, Japan. In all subjects, maximum intima-media thickness (max-IMT) in all carotid arteries, and mean-IMT and mean blood flow volume (BFV) in the common carotid arteries (CCA) were measured by ultrasonography; endothelial function was assessed by flow-mediated vasodilation of the brachial artery (%FMD). Serum DHEAS and classical cardiovascular risk factors were also evaluated. Statistical significance was determined by multiple regression analysis to elucidate independent determinants of max-IMT, mean-IMT, mean CCA-BFV, and %FMD., Results: Serum DHEAS levels were higher in males than in females. Multiple regression analysis revealed that DHEAS was an independent negative factor for both max-IMT and mean-IMT in males but not in females. In contrast, DHEAS was the sole positive factor for mean CCA-BFV in females but not in males. In addition, there was no significant relationship between %FMD and DHEAS regardless of sex and other confounding factors., Conclusion: Although DHEAS is not involved in endothelial function, DHEAS is inversely associated with sex-dependent diverse carotid atherosclerosis such as increased max-IMT and mean-IMT in males and decreased CCA-BFV in females., (Copyright 2010 Elsevier Ireland Ltd. All rights reserved.)

Aims: It was reported that administration of angiogenic growth factors can augment collateral growth in ischemic tissues. It is assumed that angiogenic effects of cell transplantation may be mainly mediated by secretion of angiogenic cytokines. We tested feasibility of clinical use of ONO-1301, a synthetic small molecule that stimulates secretion of growth factors from various cell types, to treat patients with chronic myocardial ischemia., Main Methods: Effects of ONO-1301 on fibroblasts and endothelial cells were evaluated in vitro. We examined the efficacy of local delivery of ONO-1301 in models of rat hindlimb ischemia and swine chronic ischemic myocardium., Key Findings: ONO-1301 stimulated hepatocyte growth factor secretion from human fibroblasts. ONO-1301 promoted vascular-like tube formation by endothelial cells in vitro. Direct injection of a slow-release form of ONO-1301 (SR-ONO) to rat hindlimb ischemic muscle enhanced perfusion recovery. In a swine cardiac ischemia model, direct injection of SR-ONO into the ischemic myocardium significantly augmented collateral formation (SR-ONO vs. control; 1.7+/-0.2 vs. 1.0+/-0.2 Rentrop score), with improved local ventricular wall motion, reduced enlargement of left ventricular diastolic volume (49.5+/-1.9 mL vs. 59.7+/-4.2 mL) and increased cardiac index (4.2+/-0.1 vs. 3.4+/-0.2 L/min/m(2)). Histological analysis revealed that SR-ONO suppressed fibrosis in ischemic tissue (collagen volume fraction; 7.5+/-1.1% vs. 12.8+/-2.2%) and enhanced neovascularization (capillary density, 275.6 vs. 159.3/mm(2); arterioles 36.6 vs. 25.5 /mm(2))., Significance: Local delivery of SR-ONO might be effective for therapeutic angiogenesis and propose that local administration of slow-release of synthetic small molecules represents new strategy for therapeutic angiogenesis.