bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 660: Local Hemodynamic Forces and Aqueous Cigarette Smoke Extract Affect Development of Endothelial Dysfunction
Authors: Giebe Sindy , Brunssen Coy , Brux Melanie , Cockcroft Natalia , Hewitt Katherine , Morawietz Henning 
Published: July 2021

Endothelial dysfunction is one of the first steps in the development of atherosclerosis. This proinflammatory phenotype is associated with decreased bioavailability of nitric oxide and a corresponding expression profile in the endothelial cells. Tobacco smoking promotes development of atherosclerotic plaques and local hemodynamic forces are key stimuli in this process. Low laminar flow is involved in the development of an unstable plaque phenotype, while high laminar flow has atheroprotective role. The molecular mechanisms controlling plaque stability in response to tobacco smoking remain largely unknown so far. Therefore, we exposed human endothelial cells to cigarette smoke extract (CSEaq) under disturbed flow conditions.
Primary human endothelial cells were stimulated with increasing dosages of CSEaq for 24h. Cell viability was reduced by CSEaq in a dose-dependent manner. The impact of specific flow conditions and different doses of CSEaq on the expression of atherosclerosis-related genes was investigated using a cone-and-plate viscometer. High laminar flow induced elongation of endothelial cells in the direction of flow, increased eNOS expression and NO release in a time-dependent manner. This increase was inhibited by CSEaq. Low laminar flow showed no effect on eNOS expression and NO release. The NRF2 antioxidative defense system was also induced by high laminar flow. NRF2 and NRF2 target genes HMOX1 and NQO1 were strongly activated by CSEaq. Furthermore, we monitored the expression of proinflammatory genes. CSEaq strongly induced adhesion molecule ICAM-1. Interestingly, VCAM-1 was unaffected by CSEaq. Induction of endothelial NADPH oxidase isoform 4 by CSEaq was prevented by high laminar flow. Catalase expression was not affected by flow and CSEaq, whereas CSEaq transiently increased SOD1 expression. Endothelial wound healing was improved by atheroprotective high laminar flow. Low flow did not affect wound healing. Furthermore, high laminar flow decreased adhesion of monocytes to endothelial cells, compared to low flow.
We suggest novel molecular mechanisms how tobacco smoking promotes the development of endothelial dysfunction. This can contribute to the formation of an unstable atherosclerotic plaque phenotype.
Abstract 224: Detoxification versus Healthy Aging: Aryl Hydrocarbon Receptor Deficiency Improves Vessel Functionality and Increases Healthy Lifespan
Authors: Altschmied Joachim , Eckers Anna , Jakob Sascha , Heiss Christian , Goy Christine , Brinkmann Vanessa , Ventura Natascia , Haendeler Judith 
Published: July 2021

Development of age-associated vascular diseases like atherosclerosis depends not only on genetic predisposition but also on environmental influences. Ligands of the aryl hydrocarbon receptor (AhR), a ubiquitously expressed transcription factor upregulating detoxifying enzymes, like dioxin and benzo[a]pyrene (BaP) have been shown to promote atherosclerosis. Furthermore, recovery of the blood flow after hindlimb ischemia is significantly enhanced in AhR-deficient mice demonstrating increased angiogenesis in the absence of AhR. Thus, there seems to be a link between AhR, vessel functionality and age-related cardiovascular diseases.
To investigate the role of the AhR in health span and vessel function, we analyzed AhR-deficient Caenorhabditis elegans, vessel stiffness in AhR-knockout mice and human subjects of different age and with varying levels of AhR expression as well as functional parameters in primary human endothelial cells (EC) after AhR activation.
AhR-deficient C. elegans showed not only an extended life span, but also enhanced motility. In AhR-knockout mice, we observed a reduced PWV in both old and young animals, suggesting that AhR impairs vessel function already at young age. Concomitantly, eNOS phosphorylation at serine 1178, a surrogate marker for eNOS activation, was enhanced in aortas of knockout animals. In line with this, the AhR agonist BaP increased an inhibitory phosphorylation on eNOS in EC. Moreover, BaP reduced migration of EC without changes in proliferation or apoptosis, an effect that was reversed by addition of the AhR antagonist 3’methoxy-4’nitroflavone. In human subjects we demonstrated not only a positive correlation between age and pulse wave velocity (PWV), a readout for vessel stiffness, but also between AhR expression in blood cells and PWV, again suggesting a negative impact of AhR on vessel functionality.
Our data demonstrate that loss of AhR extends life span as well as health span in C. elegans. Knockout of AhR in mice leads to improvement of vessel functionality by decreasing vessel stiffness. Finally, the PWV in humans positively correlates not only with age but also with the expression of AhR. Thus, AhR expression may be useful as a new predictor of healthy aging from nematodes to humans.
Abstract 316: Paraoxonase 1 (PON1) Promotes the Cholesterol Efflux and Regulates the Reverse Cholesterol Transport (RCT)
Authors: Ikhlef Souade , Berrougui Hicham , Khalil Abdelouahed 
Published: July 2021

Paraoxonase 1 (PON1) is a High Density Lipoprotein (HDL) associated enzyme which contributes to the antioxidant and anti-inflammatory properties of HDL. It also stimulates cholesterol efflux mediated by HDL. The purpose of this study is to determine the mechanism by which PON1 regulates this antiatherogenic activity of HDL. The oxidized phospholipids hydrolysis by PON1 results in the formation of Lysophosphatidylcholine (LPC). The phospholipase PON1 activity effect on the cholesterol efflux and the gene and protein expression were determined in vitro on J774 macrophages cells and was also determined in vivo on C57/BL6 male mice.
Our results show that due to its phospholipase activity, PON1 hydrolyzes oxidized LDL (oxLDL) and contributes to the formation of LPC, which stimulates cholesterol efflux from macrophages. Our results show that PON1 induced the expression of ABCA1 cholesterol transporters. Western blot as well as qPCR analysis show that PON1 stimulate PPARγ and LXRα nuclear receptors expression. Moreover, the use of ABCA1, PPARγ and LXRα inhibitors (respectively DIDS, GGPP and GW9662) affects the capacity of PON1 to stimulate cholesterol efflux, in particular by decreasing the proteins expression of interest (ABCA1, PPARγ and LXRα). Incubation of macrophages with purified LPC with macrophages induces a high expression of PPARγ-LXRα-ABCA1 pathway. Incubation of macrophages with PON1-oxLDL mixture and their injection to mice increase significantly the reverse cholesterol transport. Our results show that tPON1 stimulate both cholesterol efflux and RCT. via the regulation of the PPARγ-LXRα-ABCA1 pathway. This effect is attributed to the phospholipase activity of PON1 which mediates the hydrolysis of ox-LDL to form LPC.
Abstract 585: E3 ubiquitin-protein Ligase Casitas B Lineage Lymphoma b Deficiency Aggravates Atherosclerosis
Authors: Smeets Esther , Seijkens Tom , den Toom Myrthe , Meiler Svenja , Lutgens Esther 
Published: July 2021

E3 ubiquitin ligase Casitas B lineage Lymphoma b (Cbl-b) is a negative regulator in peripheral T cell activation. Cbl-b deficient T cells are hyper-reactive due to CD28-independent activation. Here we studied the effect of Cbl-b deficiency on T cell homeostasis in hypercholesterolemia and on atherogenesis in 20 wk old Cbl-b-/-/ApoE-/- mice.
Flow cytometric analysis of lymphoid tissues and aortic arches showed decreased CD4+:CD8+ T cell ratios in Cbl-b-/-/ApoE-/- mice. Cbl-b deficiency induced central memory CD8+ T cells expansion, whereas the proportion of naïve T cells decreased. We found that Cbl-b deficient CD8+ T cells are less apoptotic as indicated by decreased AnnexinV positivity and elevated expression of anti-apoptosis markers, such as Bcl-2. Pro-inflammatory, TNFa and IFNy, and cytotoxicity markers, granzyme B, are increased in Cbl-b deficient CD8+ T cells.
As expected from the increase of CD8+ T-cells in the aortic arch, Cbl-b-/-/ApoE-/- mice showed significantly more plaque development in the aortic root. The plaques contained higher leukocyte and T cell counts, but contained surprisingly less macrophages. The latter is caused by decreased monocyte recruitment resulting from lower MCP-1 levels. Moreover, the excess of CD8+ T cells induced enhanced cell death of macrophages. In vitro co-culture of Cbl-b deficient and wildtype CD8+ T cells with bone marrow derived macrophages revealed enhanced macrophage apoptosis in increased CD8+:macrophage ratios, irrespective of the CD8+ T cell genotype. Expression of the M1 macrophage markers, CD115 and CD64 was upregulated in Cbl-b deficient aortic arches, whereas M2 markers, CD206 and Arg-1, were decreased.
In conclusion, we show that Cbl-b deficiency decreases CD4+:CD8+ T cell ratio during hypercholesterolemia, through reduced apoptosis and possibly less susceptibility of CD8+ T cells to regulatory T cell suppression. This contributes to exacerbated atherosclerosis in Cbl-b deficient mice. Although plaques contained an excess of lymphocytes and T-cells, and macrophages where of an M1 phenotype, macrophage counts were decreased. This was caused by low MCP-1 levels due to CD8+ T cell induced macrophage apoptosis. These results reveal that Cbl-b balances immune reactions in atherosclerosis.
Abstract 624: Resolvin E1 Inhibits Thromboxane-Induced Contraction of Rat Aorta and Human Pulmonary Artery
Authors: Jannaway Melanie , Torrens Christopher , Warner Jane A , Sampson Anthony P 
Published: July 2021

Thromboxane is a vasoactive omega-6-derived lipid implicated in hypertension. Omega-3 fatty acid derivatives including resolvin (Rv) E1 have important roles in the resolution of inflammation, but their ability to mediate vasomotor activity is unknown. We assessed whether RvE1 modulates contraction of rat thoracic aorta and human pulmonary artery (HPA) in vitro.
Rats were culled by CO2 inhalation and cervical dislocation, and the thoracic aorta was removed. HPA were obtained with informed consent from lung tissue of surgical patients at Southampton General Hospital. Segments of aorta or HPA were incubated in DMEM-F12 with or without RvE1 (10 nM, 100 nM or 300 nM) for 1 or 24 hours, and then mounted on a wire myograph. Mounted segments were bathed at 37[[Unable to Display Character: &#61616;]]C in Kreb’s buffer, gassed (95%/5% O2/CO2) and set to 1.5 g of baseline tension. Functional integrity was confirmed by a contractile response to 125 mM KPSS. After washing to restore baseline tension, a cumulative concentration-response curve was defined to the stable thromboxane A2 mimetic U46619 (1 nM - 1 μM). Contractions are expressed as percent of KPSS response and differences determined by two-way ANOVA and by pairwise comparisons.
In rat aorta, treatment with RvE1 (10 nM) significantly shifted the U46619 curve rightwards, increasing the EC50 value 13-fold from 0.13 μM to 1.75 μM after 1 hour (n=5), and 4-fold from 0.093 μM to 0.41 μM after 24 hours (n=5). In contrast, 300 nM RvE1 caused no significant change in EC50 (1 hour 0.11 μM; 24 hours 0.097 μM, n=5).
In HPA segments, RvE1 (10 nM, 1 hour) increased the U46619 EC50 value 7-fold from 0.0079 μM to 0.054 μM (n=3), with a preliminary experiment suggesting a similar outcome after 24 hours. Higher concentrations of RvE1 had no significant effect, suggesting the relaxant action of RVE1 has a bell-shaped response curve. In preliminary experiments, RvE1 inhibited U-46619 contractions of bronchiolar airways from the same human donors.
Resolvin E1 is known for its immunomodulatory actions on leukocytes and also inhibits U46619-induced aggregation of platelets, but our results are the first evidence that this pro-resolution mediator can also inhibit contractions of intact vasculature from rat and human lung induced by a thromboxane mimetic.
Abstract 660: Inhibition of 14q32 “AngiomiR” MicroRNA-494 Reduces Atherosclerotic Lesion Formation, Increases Plaque Stability and Lowers Cholesterol Levels
Authors: Welten Sabine , Wezel Anouk , Bastiaansen Antonius , de Jong Rob , de Vries Margreet , Goossens Eveline , Peters Erna , Boonstra Martin , Kandimalla Ekambar , Kuiper Johan , Quax Paul , Bot Ilze , Nossent Yael 
Published: July 2021

We have shown that inhibition of 14q32 microRNAs (miRs) miR-329, miR-487b, miR-494 and miR-495 increased both angiogenesis and arteriogenesis, leading to a 40% increase in blood flow recovery after ischemia. As many vascular remodelling processes share underlying mechanisms, we also investigated the effects of 14q32 microRNA inhibition in atherosclerosis
When looking at expression patterns of 14q32 “angiomiRs”, we found that miR-494 was abundantly expressed in murine tissues involved in atherosclerosis, including the liver, spleen and carotid arteries. When looking at human carotid artery lesions, we found that miR-494 expression was doubled in vulnerable plaques compared to plaques of a stable phenotype.
We used Gene Silencing Oligonucleotides (GSOs) to inhibit miR-494 in ApoE-/- mice, after placing semi-constrictive collars around both carotid arteries for 28 days to induce atherosclerotic lesion formation. We observed efficient uptake of IRD-800CW-labeled GSO-494 into the carotid artery, leading to a 50% reduction of miR-494 expression and significant upregulation of multiple anti-atherogenic target genes. Atherosclerotic lesion formation was drastically reduced in mice treated with GSO-494 (GSO-Control: 47 ± 11*103 μm2; GSO-494: 16 ± 3*103 μm2), while plaque stability was increased, determined by both a decrease in necrotic core size and an increase in plaque collagen content. Furthermore, inhibition of miR-494 resulted in increased cholesterol efflux in vitro (p<0,05). Indeed, in vivo, plasma total cholesterol levels and VLDL fractions were decreased after miR-494 inhibition (GSO-Control: 30.4 ± 1.1 mM; GSO-494: 26.4 ± 0.7 mM).
In conclusion, inhibition of miR-494 results in smaller, more stable, atherosclerotic lesions, while simultaneously improving neovascularization. The so-called Janus phenomenon, which is a major drawback in translation towards the clinic, is hereby circumvented. The 14q32 miR-494 therefore provides a promising novel therapeutic target in prevention and treatment of atherosclerotic diseases.
Abstract 679: Modeling Thoracic Aortic Aneurysm of Bicuspid Aortic Valve Patients with Induced Pluripotent Stem Cells Reveals Distinct Phenotypes of Smooth Muscle Cells from Different LIneages
Authors: Jiao Jiao , Xiong Wei , Wang Lunchang , Chen Eugene , Yang Bo 
Published: July 2021

Ascending aortic aneurysm occurs in 35%-68% patients with bicuspid aortic valves (BAV), which is more frequently than it does in patients with normal trileaflet aortic valves (TAV). In contrast to recurrent aneurysms of the ascending aorta, descending aortic aneurysms is very rare in patients with BAV. Vascular Smooth Muscle Cells (SMCs) make up the media of the aortic walls, and their contractile properties help sustain vessel tone. Interestingly, ascending aorta is populated by SMCs arising from neural crest and descending aorta by SMCs from paraxial mesoderm. An intriguing hypothesis is that the distinct susceptibility of aneurysm in the ascending and descending aorta in patients with BAV is due in part to disparities in SMC embryonic origins.
To prove our hypothesis, we used an induced Pluripotent Stem Cells (iPS) model system to generate SMCs from neural crest and paraxial mesoderm. Firstly, iPSCs were established from a patient with BAV and ascending thoracic aortic aneurysm (BAV/TAA) and two control patients with normal aorta and TAV. The iPSCs pluripotency was verified by standard stem cell markers and teratoma formation. Neural crest stem cells (NCSCs) were differentiated from iPSCs and expressed neural crest markers, including P75, HNK1, AP2 and Sox9. In parallel, paraxial mesoderm cells (PMCs) were differentiated from iPSCs and expressed specific markers, including TCF15, TBX6, Meox1 and Pax1. The SMCs differentiated from both lineages had expression of SMC markers including MYH11, CNN1, ACTA2, SM22α. Interestingly, SMCs derived from BAV-NCSCs had significantly decreased in MYH11 and ACTA2 gene expression and impaired contractile property by gel contraction assay compared to SMCs derived from control-NCSCs. However, SMCs from BAV-PMCs had similar level of expression of MYH11 and ACTA2, and strong contractile activity with Carbacol treatment compared to SMCs derived from control PMCs. In conclusion, the iPS model system revealed decreased expression of contractile proteins and impairment of contractility in SMCs derived from NCSCs in BAV patient, but not in the SMCs derived from paraxial mesoderm cells. The high susceptibility of aneurysm in the ascending aorta in patients with BAV might be partly due to embryonic origin of the SMCs.
Abstract 692: Class II HDACs Are Required During Early Stage Mouse Embryonic Stem Cell Differentiation in Response to Nitric Oxide
Authors: Illi Barbara , Spallotta Francesco , Rosati Jessica , Mattiussi Stefania , Nanni Simona , Rotili Dante , Valente Sergio , Mai Antonello , Farsetti Antonella , Capogrossi Maurizio C , Gaetano Carlo 
Published: July 2021

INTRODUCTION & BACKGROUND: We have recently described that in mouse embryonic stem cells (ES) laminar shear stress provides chromatin programming signals. This effect is similar to that of nitric oxide (NO) which directly promotes cardiomyogenesis underlying the possible presence of a common mechanism of action the characterization of which has been the object of the present study.
METHODS & RESULTS: ES were treated with the NO donor DETANO from 1 to 24 hours (h) in the presence of absence of leukaemia inhibitory factor (LIF). In LIF-deprived cells the NO donor determined a marked global reduction in histone H3 acetylation paralleled by the expression of a number of cardiovascular markers. In this condition the stemness-associated gene product Oct4 decreased rapidly at mRNA and protein level underlying the potential opening of a NO-dependent differentiation program. Further class-II histone deacetylase (HDAC) 4, 5, and 7, rapidly shuttled to nucleus upon LIF deprivation. This phenomenon was transient as HDAC molecules returned to the cytoplasm in about 6 h. Intriguingly, the exposure of ES to the NO donor allowed the nuclear retention of these enzymes still detectable at the 6 h time-point. Further, we found that NO treatment stimulated the formation of nuclear complexes including the class II HDACs 4, 5 and the protein phosphatase 2A. Remarkably, ES treatment with the class II selective inhibitor MC 1568 prevented ES differentiation in the presence of NO.
CONCLUSIONS: These results suggest a potential role for class II HDACs in the NO-dependent early stage of ES commitment upon LIF removal.
Abstract 803: Diesel Exhaust Inhalation Enhances Thrombus Formation In Man
Authors: Lucking Andrew J , Lundback Magnus , Mills Nicholas L , Faratian Dana , Cassee Fleming , Donaldson Ken , Boon Nicholas , Badimon Juan J , Sandstrom Thomas , Blomberg Anders , Newby David E 
Published: July 2021

Background: Transient exposure to traffic-derived air pollution may be a trigger for acute myocardial infarction although the mechanism is unclear. The aim of this study was to investigate the effect of diesel exhaust inhalation on thrombus formation in man using an ex vivo model of thrombosis.
Methods and Results: In a double-blind randomized cross-over study, 20 healthy volunteers were exposed to diluted diesel exhaust (300 μg/m3) or filtered air during intermittent exercise for 1 or 2 hours. Thrombus formation, coagulation, platelet activation and inflammatory markers were measured at 2 and 6 hours after exposure. Thrombus formation was measured using the Badimon ex vivo perfusion chamber at low (212 /s) and high (1,690 /s) shear rates with porcine aortic tunica media as the thrombogenic substrate. Specimens were fixed, stained and thrombus area measured using computerized planimetry. Compared to filtered air, diesel exhaust increased thrombus formation in the low and high shear chambers by 24.2% (p<0.001) and 19.1% (p<0.001) respectively. This increased thrombogenicity was seen at two and six hours, and using two different types of diesel exposure. Although there were no effects on coagulation variables, diesel exhaust inhalation increased platelet-neutrophil (6.5% to 9.2%; P<0.05) and platelet-monocyte (21.0% to 25.0%; P<0.05) aggregates 2 hours following exposure.
Conclusions: Inhalation of diesel exhaust increases ex vivo thrombus formation and causes platelet activation in man. These findings provide a potential mechanism that links exposure to traffic-derived air pollution with acute atherothrombotic events including acute myocardial infarction.
Abstract 1066: Cardiac-restricted Disruption of Supressor of Cytokine Signaling-3 Leads to Dilated Cardiomyopathy in a gp130 Independent Manner
Authors: Yajima Toshitaka , Yasukawa Hideo , Zhou Hanbing , Yajima Tomoko , Lim Byung-Kwan , Kirk Knowlton 
Published: July 2021

We recently reported that cardiac-restricted overexpression of suppressor of cytokine signaling-3 (SOCS3) markedly increases cardiac myocyte susceptibility to virus infection. This suggests that endogenous SOCS3 also has significant biological effect in the cardiac myocyte. To understand physiological role of SOCS3 in the cardiac myocyte, we generated cardiac-specific SOCS3 knockout mice. The mice were born at the expected Mendelian ratio, but developed cardiac dysfunction (%FS; wt: 45±2.6 vs. ko: 31±4.5, mean±SE, n=8, p=0.017, 5-month-old) estimated by echocardiogram from 5 months of age and died with signs of dyspnea by 7 months of age. Postmortem analysis revealed significant pleural effusions and ascites, consistent with the presence of heart failure. Histological analysis showed that the heart has a thin left and right ventricular walls with chamber dilatation; however, typical findings of a myopathic heart such as myocyte disarray, inflammation and fibrosis were only rarely observed. Ultrastructure analysis of the dilated heart samples showed intact myofibrils, mitochondria, intercalated discs and gap junctions, suggesting that the myocyte had non-structural abnormalities that led to functional impairment. Unexpectedly calcium transients in the isolated adult myocytes from the failing hearts were significantly increased as compared to those from age-matched normal hearts (Fura-2 intensity ratio 340/380 nm; wt: 0.44±0.01 vs. ko: 0.54±0.01, mean±SE, n=3, p<0.0002), suggesting the decreased calcium sensitivity of SOCS3 deficient myocytes. We also observed spontaneous ventricular tachycardia in the knockout mice by telemetry analysis. Since SOCS3 has been reported to be a crucial negative-feedback regulator of gp130 signaling in vivo, we sought to determine whether the phenotype is due to overactivation of cardiac gp130 signaling. While gp130 downstream signaling such as STAT3, ERK and AKT pathways were significantly activated in the knockout heart, cardiac-specific knockout of both gp130 and SOCS3 did not rescue the dilated cardiomyopathy phenotype.
Conclusion: These results indicate that a gp130-independent mechanism is responsible for the dilated cardiomyopathy that occurs in SOCS3 deficient hearts.