SciCombinator

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Concept: VCAM-1

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Pomegranate (Punica granatum L.) juice (PJ) contains different types of antioxidants and bioactive polyphenols and has been reported to promote cardiovascular health through several mechanisms. The present study aimed to examine the effects of 2-week intake of fresh PJ on blood pressure, flow-mediated dilatation (FMD), serum lipid profile and concentrations of inflammatory and endothelial function biomarkers. Twenty-one hypertensive patients (aged 30-67 years) were recruited into the trial and assigned to receive either PJ (150 ml/day in a single occasion between lunch and dinner; n = 11) or the same amount of water (n = 10) for a period of 2 weeks. Systolic (SBP) and diastolic (DBP) pressures together with FMD and serum concentrations of lipid profile parameters, apolipoproteins A and B, intracellular adhesion molecule-1 (ICAM-1), vascular endothelial adhesion molecule 1 (VCAM-1), E-selectin, high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) were measured at baseline and at the end of trial. PJ consumption was associated with significant reductions in SBP (p = 0.002) and DBP (p = 0.038) but not FMD (p > 0.05). Serum levels of VCAM-1 (p = 0.008) were significantly reduced by PJ while those of E-selectin were elevated (p = 0.039). However, no significant effect was observed from PJ on serum levels of ICAM-1, hs-CRP, lipid profile parameters, apolipoproteins and IL-6 in any of the study groups (p > 0.05). Consumption of PJ for 2 weeks has effective hypotensive effects, and may improve endothelial function by decreasing serum concentrations of VCAM-1. These findings suggest PJ as a beneficial cardioprotective supplement for hypertensive subjects. Copyright © 2013 John Wiley & Sons, Ltd.

Concepts: Inflammation, Atherosclerosis, Antioxidant, Cardiovascular disease, Blood pressure, C-reactive protein, VCAM-1, Pomegranate

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Myocardial infarction (MI) leads to a systemic surge of vascular inflammation in mice and humans, resulting in secondary ischemic complications and high mortality. We show that, in ApoE(-/-) mice with coronary ligation, increased sympathetic tone up-regulates not only hematopoietic leukocyte production but also plaque endothelial expression of adhesion molecules. To counteract the resulting arterial leukocyte recruitment, we developed nanoparticle-based RNA interference (RNAi) that effectively silences five key adhesion molecules. Simultaneously encapsulating small interfering RNA (siRNA)-targeting intercellular cell adhesion molecules 1 and 2 (Icam1 and Icam2), vascular cell adhesion molecule 1 (Vcam1), and E- and P-selectins (Sele and Selp) into polymeric endothelial-avid nanoparticles reduced post-MI neutrophil and monocyte recruitment into atherosclerotic lesions and decreased matrix-degrading plaque protease activity. Five-gene combination RNAi also curtailed leukocyte recruitment to ischemic myocardium. Therefore, targeted multigene silencing may prevent complications after acute MI.

Concepts: Inflammation, Monocyte, Atherosclerosis, Cell adhesion molecule, Immunoglobulin superfamily, VCAM-1, E-selectin, P-selectin

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Rheumatic heart disease (RHD) is a chronic condition characterized by fibrosis and scarring of the cardiac valves and damage to the heart muscle, leading to congestive heart failure and death. This prospective cohort study was conducted to investigate the possible relation between the levels of serum adhesion molecules and acute rheumatic fever (ARF) carditis, valvular insult severity, and residual valvular lesion after improvement of rheumatic activity. Serum levels of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin were assayed by enzyme-linked immunoassay (ELISA) for 50 children with ARF carditis during activity and after improvement and for 50 healthy children as control subjects. After the acute attack, patients were followed up regularly to detect residual valvular lesion. The serum levels of these adhesion molecules were significantly higher in the patients than in the control group (p < 0.001). In addition, the levels of serum adhesion molecules were significantly higher in the patients with severe carditis than in the patients with mild to moderate carditis (p < 0.001). Among the severe carditis group, the level of serum adhesion molecules was significantly higher among the patients with heart failure than among the patients without heart failure (p < 0.001). Furthermore, the pretreatment serum levels of ICAM-1 and VCAM-1 were significantly higher among the patients with residual valve lesion (p = 0.002) than among those without the lesion (p < 0.001). The cutoff values were obtained for the prediction of residual valvular lesion (ICAM-1, >1,032.3 μg/ml; VCAM-1, >3,662.3 μg/ml; E-selectin, >104.8 μg/ml). Finally, by combining the three adhesion molecules in a single prediction model, the highest area under the curve (AUC) ± standard error (SE) was obtained (0.869 ± 0.052), and the positive likelihood ratio for having a residual valvular lesion was increased (17.33). Levels of serum adhesion molecules could predict residual valvular lesions in RHD patients. The authors recommend that the serum level of adhesion molecules be measured in all cases of ARF carditis.

Concepts: Cardiology, Heart, Rheumatic fever, Cell adhesion molecule, Rheumatism, Intercellular adhesion molecule, VCAM-1, Heart valve

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The effects of particulate matter (PM) on endothelial cells have been evaluated in vitro by exposing isolated endothelial cells to different types of PM. Although some of the findings from these experiments have been corroborated by in vivo studies, an in vitro model that assesses the interaction among different cell types is necessary to achieve more realistic assays. We developed an in vitro model that mimics the alveolar-capillary interface, and we challenged the model using TiO(2) nanoparticles (TiO2-NPs). Human umbilical endothelial cells (HUVECs) were cultured on the basolateral side of a membrane and pneumocytes (A549) on the apical side. Confluent co-cultures were exposed on the apical side to 10 μg/cm(2) of TiO2-NPs or 10 ng/mL of TNFα for 24 h. Unexposed cultures were used as negative controls. We evaluated monocyte adhesion to HUVECs, adhesion molecule expression, nitric oxide concentration and proinflammatory cytokine release. The TiO2-NPs added to the pneumocytes induced a 3- to 4-fold increase in monocyte adhesion to the HUVECs and significant increases in the expression of adhesion molecules (4-fold for P-selectin at 8 h, and about 8 to 10-fold for E-selectin, ICAM-1, VCAM-1 and PECAM-1 at 24 h). Nitric oxide production also increased significantly (2-fold). These results indicate that exposing pneumocytes to TiO2-NPs causes endothelial cell activation.

Concepts: Inflammation, Atherosclerosis, Blood vessel, In vivo, Endothelium, Nitric oxide, Vasodilation, VCAM-1

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OBJECTIVES:: In our previous research the antihypertensive properties of lycopene-containing tomato oleoresin have been revealed. The present study was aimed to assess if oleoresin interferes in the inflammatory signalling in endothelial cells, imitating reduction of inflammatory processes in the vessel wall and in this way to propose the mechanism for the reduction of blood pressure by oleoresin. METHODS AND RESULTS:: A wide number of functional and inflammatory markers were investigated in two cultured endothelial cell models [EA.hy926 and human umbilical vein endothelial cell (HUVEC)], exposed to oleoresin and carotenoids lycopene and lutein. All the carotenoids significantly improved basic endothelial function as measured by increased nitric oxide and decreased endothelin (ET-1) release. They were effective in attenuation of inflammatory nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signalling: decrease of tumour necrosis factor-alpha (TNF-α)-induced leukocytes adhesion, expression of adhesion molecules inter-cellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), and nuclear translocation of NF-κB components as well as some revert of inhibitor of kappa B (IκB) ubiquitination. In addition, the carotenoids were able to inhibit NF-κB activation in transfected endothelial cells. When combined with lutein, oleoresin exerted synergistic effect on preclusion of leukocytes adhesion. CONCLUSIONS:: Prevention of over-expression of adhesion molecules through inhibition of NF-κB signalling may be one of the main mechanisms driving carotenoids to attenuate inflammatory leukocyte adhesion to endothelium. This is the first profound study on the mechanisms involved in the positive action of natural tomato products in endothelial cells.

Concepts: Inflammation, Atherosclerosis, Blood vessel, Cell adhesion molecule, Endothelium, Nitric oxide, Vasodilation, VCAM-1

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Inhibitor of differention-3 (Id3) promotes B cells homing to the aorta and atheroprotection in Apoe(-/-) mice. We sought to determine the impact of loss of Id3 in the Ldlr((-/-)) mouse model of diet-induced atherosclerosis and identify novel Id3 targets in the vessel wall.

Concepts: Monocyte, Gene, Atherosclerosis, Macrophage, Blood vessel, VCAM-1

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BACKGROUND:: Switching from boosted protease inhibitors (PI/r) to raltegravir (RAL) results in a better plasma lipid profile than continuing PI/r. Whether this strategy affects plasma biomarkers associated with atherosclerosis is unknown. METHODS:: We assessed 48-week changes in fasting lipids and several biomarkers including serum high-sensitivity C-reactive protein (hsCRP), monocyte chemoattractant protein 1 (MCP-1), osteoprotegerin, interleukin (IL) 6, IL-10, tumor necrosis factor alpha (TNF-α), intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin and P-selectin, adiponectin, insulin, and D-dimer in otherwise healthy, virologically suppressed HIV-infected patients treated with PI/r who randomly switched from PI/r to RAL or continued with PI/r in the SPIRAL trial. Biomarkers and lipids at baseline and 48-week changes between both study arms were compared. Correlations between changes in biomarkers and changes in lipids were also evaluated. RESULTS:: Of 273 patients initiating study drugs in the SPIRAL trial, 233 (119 RAL, 114 PI/r) remained on allocated therapy for 48 weeks and had sera available for the purpose of this substudy. Triglycerides (-28%, P < 0.0001), total (-14%, P < 0.0001), low-density lipoprotein (-9%, P = 0.0069), and high-density lipoprotein (-10%, P = 0.0017) cholesterol decreased in RAL relative to the PI/r group. Among biomarkers, hsCRP (-40%, P < 0.0001), MCP-1 (-20%, P = 0.0003), osteoprotegerin (-13%, P = 0.0024), IL-6 (-46%,P < 0.0001), TNF-α (-27%, P = 0.0011), insulin (-26%, P < 0.0001), and D-dimer (-8%, P = 0.0187) decreased in RAL relative to PI/r group, whereas IL-10 (+1%, P = 0.7773), ICAM-1 (-6%, P = 0.1255), VCAM-1(0%, P = 0.8671), E-selectin (-9%, P = 0.2174), P-selectin (-6%, P = 0.3865), and adiponectin (+8%, P = 0.2028) remained unchanged. Biomarkers and lipids changes at 48 weeks were weakly correlated. CONCLUSION:: Switching from PI/r to RAL induced significant changes in several cardiovascular biomarkers that were not completely explained by lipid changes.

Concepts: Cholesterol, Inflammation, Atherosclerosis, Cardiovascular disease, Cell adhesion molecule, Lipid, Tumor necrosis factor-alpha, VCAM-1

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The process of atherosclerosis is affected by interactions among numerous biological pathways. Accumulating evidence shows that endoplasmic reticulum (ER) stress plays a crucial role in the development of atherosclerosis. Rho-kinase is an effector of small GTP-binding protein Rho, and has been implicated as an atherogenic factor. Previous studies demonstrated that fasudil, a specific Rho-kinase inhibitor, exerts a cardioprotective effect by downregulating ER stress signaling. However, the molecular link between ER stress and Rho-kinase in endothelial cells has not been elucidated. In this study, we investigated the mechanisms by which fasudil regulates endothelial inflammation during ER stress. Tunicamycin, an established ER stress inducer, increased vascular cellular adhesion molecule (VCAM)-1 expression in endothelial cells. Intriguingly, fasudil inhibited VCAM-1 induction. From a mechanistic stand point, fasudil inhibited expression of activating transcription factor (ATF)4 and subsequent C/EBP homologous protein (CHOP) induction by tunicamycin. Furthermore, fasudil attenuated tunicamycin-induced phophorylation of p38MAPK that is crucial for the atherogenic response during ER stress. These findings indicate that Rho-kinase regulates ER stress-mediated VCAM-1 induction by ATF4- and p38MAPK-dependent signaling pathways. Rho-kinase inhibition by fasudil would be an important therapeutic approach against atherosclerosis, in particular, under conditions of ER stress.

Concepts: Inflammation, DNA, Atherosclerosis, Endoplasmic reticulum, Cell adhesion molecule, Endothelium, Unfolded protein response, VCAM-1

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The underlying cause of major cardiovascular events, such as myocardial infarctions and strokes, is atherosclerosis. For accurate diagnosis of this inflammatory disease, molecular imaging is required. Toward this goal, we sought to develop a nanoparticle-based, high aspect ratio, molecularly-targeted magnetic resonance MR imaging contrast agent. Specifically, we engineered the plant viral nanoparticle platform tobacco mosaic virus (TMV) to target vascular cell adhesion molecule (VCAM)-1, which is highly expressed on activated endothelial cells at atherosclerotic plaques. To achieve dual optical and MR imaging in an atherosclerotic ApoE-/- mouse model, TMV was modified to carry near-infrared dyes and chelated Gd ions. Our results indicate molecular targeting of atherosclerotic plaques. Based on the multivalency and multifunctionality, the targeted TMV-based MR probe increased the detection limit significantly; the injected dose of Gd ions could be further reduced by three orders of magnitude compared to the suggested clinical use, demonstrating the utility of targeted nanoparticle cargo delivery.

Concepts: Inflammation, Myocardial infarction, Atherosclerosis, Blood vessel, Cardiovascular disease, Low-density lipoprotein, Endothelium, VCAM-1

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Neutrophils are essential for innate immunity and inflammation and many neutrophil functions are β2 integrin-dependent. Integrins can extend (E(+)) and acquire a high-affinity conformation with an ‘open’ headpiece (H(+)). The canonical switchblade model of integrin activation proposes that the E(+) conformation precedes H(+), and the two are believed to be structurally linked. Here we show, using high-resolution quantitative dynamic footprinting (qDF) microscopy combined with a homogenous conformation-reporter binding assay in a microfluidic device, that a substantial fraction of β2 integrins on human neutrophils acquire an unexpected E(-)H(+) conformation. E(-)H(+) β2 integrins bind intercellular adhesion molecules (ICAMs) in cis, which inhibits leukocyte adhesion in vitro and in vivo. This endogenous anti-inflammatory mechanism inhibits neutrophil aggregation, accumulation and inflammation.

Concepts: Immune system, Monocyte, In vivo, Cell adhesion molecule, In vitro, Neutrophil granulocyte, Integrin, VCAM-1