bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 353: Elastase-Activated Stress Response of Vascular Cells
Authors: Grechowa Irina , Dorweiler Bernhard , Wallrath Anja , Horke Sven
Published: July 2021

Introduction:
Rupture of atherosclerotic plaques is the most abundant cause for stroke. The serine protease elastase plays an important role as it induces death of endothelial cells (ECs) and smooth muscle cells (SMCs), and breaks down the fibrous cap of atherosclerotic plaques. Increased elastase concentrations were found in patients with symptomatic stenosis. We previously showed that elastase activates the endoplasmic reticulum (ER) stress signaling pathway unfolded protein response (UPR) in rupture-prone plaques of human carotid artery. However, signaling pathways elicited by elastase in vascular cells were largely unknown. We hypothesized that elastase induces cell-type dependent responses in ECs, SMCs and macrophages (M[[Unable to Display Character: Ф]]).

Methods and Results:
Different forms of cell death and UPR activation were analyzed in primary and immortalized endothelial cells, coronary artery smooth muscle cells (HCASMCs) and M[[Unable to Display Character: Ф]] after treatment with human neutrophil elastase. To discriminate between the involved cell death types, three independent assays were performed. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-assay by confocal microscopy (p < .01), caspase3/7 activity by chemiluminescence-assays (p < .01) and cell-cycle analysis by flow cytometry revealed that an autophagic/apoptotic cell death was induced upon elastase treatment. This appeared specific for ECs, as it was absent in M[[Unable to Display Character: Ф]]. Necrosis (as determined by chemiluminescent lactate dehydrogenase-release assay) and necroptosis (assessed by flow cytometry) played only minor roles. The involvement of the UPR was investigated on protein and / or gene expression level. The high levels of GRP78, phospho-PERK, phospho-eIF2α, spliced XBP1 and CHOP indicate a strongly activated UPR that may give rise to the subsequent induced autophagic/apoptotic cell death.

Conclusion:
Elastase plays a significant role in plaque stability and cell survival likely through activation of a UPR/autophagic type of endothelial cell death. This may explain underlying molecular links how elastase destabilizes atherosclerotic plaques.
Abstract 361: Activation of Wnt Pathway in Macrophages During Atherosclerosis Regression
Authors: Menon Prashanthi , Vengrenyuk Yulia , Ogando Yoscar , Ramsey Stephen , Gold Elizabeth , Fisher Edward
Published: July 2021

Introduction and Objective:
Transcriptome analysis of plaque macrophages in two different mouse models of atherosclerosis regression revealed an over representation of consensus binding site sequences for the T-cell factor (TCF)/Lymphoid enhancer binding factor (LEF) family of transcription factors, suggesting canonical Wnt signaling pathway activation during regression in vivo. The canonical Wnt/β-catenin signaling pathway is important for cardiac development and regulates processes such as migration, invasion and tissue repair. However, its function in plaque macrophages is unclear. The objective of the study was to understand the role of canonical Wnt signaling in macrophages during regression using in vivo and in vitro approaches.

Methods and Results:
Immunohistochemistry of atherosclerotic arterial sections in mouse models of atherosclerosis regression (Reversa and aortic arch transplant) showed a significant increase in β-catenin expression in regressing vs. progressing macrophages. Elevated transcript levels of canonical Wnt downstream targets Ctnnb1, Lrp1 and Gja1 were detected in regressing plaque macrophages isolated by laser capture microdissection (LCM). Canonical Wnt signaling was further investigated in Wnt3a-stimulated primary bone marrow-derived macrophages (BMDM) in vitro, revealing upregulation of pathway target genes Ctnnb1 and Axin2. Furthermore, immunofluorescence analysis of BMDM stimulated with Wnt3a showed increased nuclear expression of β-catenin. Macrophage cell migration evaluated by scratch wound assay revealed a significant increase in migration in Wnt3a-treated vs. untreated BMDM.

Conclusions:
Our findings demonstrate that canonical Wnt signaling is activated in regressing plaque macrophages and regulates macrophage migration in vitro. Future studies are aimed at understanding the mechanism by which Wnt modulates macrophage migration.
Abstract 390: Use of Eptifibatide in patients with ventricular assist devices and Bleeding outcomes
Authors: Siddiqui Mohammed , Mazimba Sula , Tallaj Jose A , Pamboukian Salpy V
Published: July 2021

Background:
Pump thrombosis is a dreaded complication in patients with left ventricular assist devices (LVADs). Intravenous anticoagulation is often instituted prior to surgical pump exchange. The use of eptifibatide, a glycoprotein IIb/IIIa inhibitor has been reported with data showing increased adverse events by as much as 65%. This study evaluated eptifibatide use for suspected pump thrombus/thrombosis and bleeding outcomes

Methods:
This was a single center retrospective study of eptifibatide use in patients with suspected pump thrombus. All LVAD patients who received eptifibatide for suspected pump thrombus from October 22, 2011, through April 19, 2014 were included. Pump thrombosis was suspected if one or more was present: elevated lactate dehydrogenase, decreased haptoglobin, elevated free plasma hemoglobin and persistently elevated powers. The study was approved by the institutional board review.

Results:
A total of 17 patients (13 Heart Mate II, 3 Heart Ware and 1 Abiomed AB5000 LVAD) with 25 admission events received eptifibatide (dose range, 0.25-2 μg/kg/min). The mean time from device implantation to eptifibatide therapy was 660 days (range: 1 - 1809 days). 9 (36%) patients underwent pump exchange while the rest resolved medically. 7 (28%) patients had confirmed Pump/LVAD thrombus while 3 (12%) had major bleeding events (1-GI, 1-Oral and 1-Acute Intracranial Hemorrhage) requiring drug interruption. 8(47%) patients had combined 11 minor mucosal bleeding events (Oral-2, GU-5, GI-1 and Nasal-3) that did not require therapy interruption. 2 of the 3 (67%) patients with major bleeding died as a result.

Conclusions:
Minor bleeding is more common than major bleeding with eptifibatide use in patients with suspected pump thrombus. Comparative effectiveness studies of eptifibatide therapy in suspected pump thrombosis are needed to assess risk benefit ratio.
Abstract 391: Platelet CD40L Affects Thrombus Formation via Phosphatidylinositol 3-kinase ß, But Not Via CD40 or IKKα
Authors: Kuijpers Marijke J , Mattheij Nadine J , Cipolla Lina , van Geffen Johanna P , Lawrence Toby , Donners Marjo M , Boon Louis , Gerdes Norbert , Torti Mauro , Noels Heidi , Cosemans Judith M , Lievens Dirk , Lutgens Esther , Heemskerk Johan W
Published: July 2021

Objective:
To investigate the roles and signaling pathways of CD40L and CD40 in platelet activation and thrombus formation under atherothrombotic conditions.

Approach and Results:
Mouse platelets lacking CD40L (Cd40lg
-/-
Apoe
-/-
) showed diminished αIIbβ3 activation and α-granule secretion in response to collagen receptor (GPVI) stimulation, while CD40 deficient platelets (Cd40
-/-
Apoe
-/-
) showed increased responses. ADP- or thrombin-evoked activation was unaffected. In both Cd40lg
-/-
Apoe
-/-
and Cd40
-/-
Apoe
-/-
mice, formation of multi-layered thrombi was decreased on both atherosclerotic plaque material and collagen, in comparison to controls. Addition of CD40L prior to perfusion over collagen or plaque material enhanced dense aggregate formation in Apoe
-/-
, Cd40lg
-/-
Apoe
-/-
and Cd40
-/-
Apoe
-/-
blood. CD40L or low GPVI stimulation separately did not cause platelet aggregation. But when combined, aggregation was potentiated, even in the absence of CD40. This potentiation was antagonized by inhibiting PI3Kβ, as well as in platelets from Pik3cb
R/R
mice. CD40L enhanced Akt phosphorylation at low GPVI stimulation, which was again antagonized by PI3Kβ inhibition and absent in platelets from Pik3cb
R/R
mice. Finally, Chuk1
A/A
Apoe
-/-
mice, deficient in IKKα, displayed no differences in platelet aggregation - with or without CD40L - nor in thrombus formation in whole blood, indicating that these effects are not mediated via IKKα/NFkB.

Conclusions:
Under atherothrombotic conditions, CD40L enforces collagen-dependent platelet activation, by supporting integrin αIIbβ3 activation, secretion and dense thrombus formation via PI3Kβ, but not IKKα. Since shedding of CD40L starts minutes after activation, these results point to a joint role of both platelet-bound and soluble CD40L in controlling the size of rapidly formed thrombi.
Abstract 399: Oxidized Phospholipids Regulate Inflammatory Gene Transcription via Bromodomain Containing 4 (BRD4) In Vascular Endothelial Cells
Authors: Lee Sangderk , Kim Seon-Gu , Newcomb Rachel , Yang Lihua , Rateri Debra
Published: July 2021

Objective:
Atherosclerosis is a chronic inflammatory disease initiated by monocyte infiltration into the vessel wall. Oxidized phospholipids (Ox-PL) that accumulate in the subendothelial space during hyperlipidemia elicit changes in inflammatory gene transcription and endothelial cell function. Bromodomain-containing 4 (BRD4) reads histone acetyl epigenetic modification and regulates inflammatory gene transcription controlled by the modification in the endothelial cells. In this study, we tested whether oxidized phospholipids regulates inflammatory gene transcription via histone acetyl epigenetic modification and its reader BRD4 in vascular endothelial cells.

Methods and Results:
A representative Ox-PL, Ox-PAPC (oxidized 1-palmitoyl-2-arachidonoyl-sn-glycerol-3-phosphatidylcholine), regulates over 1,500 transcripts in human aortic endothelial cells (HAECs) including inflammatory IL-8 and monocyte chemoattractant protein 1 (MCP1). Gene silencing of histone acetyl transferases (HATs) p300 and CBP also inhibited transcription of inflammatory genes in endothelial cells, suggesting that the histone acetyl epigenetic modification are involved in inflammatory gene transcription by Ox-PAPC. Small molecule inhibitors of BRD4 or BRD4 gene silencing potently and selectively repressed inflammatory gene transcription by Ox-PAPC. Microarray analysis revealed that the inhibitor downregulated hundreds of genes involved in inflammation and apoptosis. The administration of the BRD4 inhibitor JQ1(+) in LDLR null mouse showed a significant inhibition of the inflammatory responses induced by hyperlipidemia in the vascular system.

Conclusion:
Histone acetyl epigenetic modification and the reader BRD4 mediates inflammatory gene transcription by oxidized phospholipids in the endothelial cells. Targeting of BRD4 may be an efficient approach to prevent hyperlipidemia-induced inflammation and atherosclerosis.
Abstract 401: The Lineage-specific Transcription Factor PU.1 Prevents Heterochromatinization of Macrophage-specific Genes During Hematopoietic Differentiation
Authors: Floer Monique , Tagore Mohita , McAndrew Michael J , Gjidoda Alison
Published: July 2021

We are using a quantitative approach to determine the fractional occupancy of nucleosomes at gene regulatory regions (i.e. enhancers and promoters) in primary mouse macrophages. This has allowed us to determine the dynamics of nucleosome removal at regulatory regions upon pro-inflammatory gene induction (Gjidoda, A. et al. 2014 Nucleosomes are stably evicted from enhancers but not promoters upon induction of certain pro-inflammatory genes in mouse macrophages. PLoS ONE 9(4): e93971). Moreover, we are interested in understanding how an accessible chromatin architecture is established at regulatory regions during macrophage differentiation, so that the transcriptional machinery can be recruited to these sites in mature cells. These studies have shown that the lineage-specific transcription factor PU.1 has to be present in hematopoietic progenitors to mark macrophage-specific genes for later induction. Using a previously established macrophage differentiation system from a PU.1-/- mouse as well as primary macrophages, we find that in the absence of PU.1 binding to the enhancer of a macrophage-specific gene, the enhancer is bound by PRC2 as cells are differentiated into mature macrophages. This leads to wrapping of the whole gene locus into heterochromatin, which is associated with tri-methylation of H3K27 and increased nucleosome occupancy. Our results show that one role of lineage-specific transcription factors is to prevent heterochromatinization of cell-type specific genes during differentiation to allow their expression in mature cells.
Abstract 425: Lycopene Modulates T Lymphocyte Function by Modulating Th1 Responses and Treg Lymphocyte Population
Authors: Mills Lynsey M , Wilson Heather , Thies Frank
Published: July 2021

Increased lycopene intake might have cardiovascular benefits, potentially through anti-inflammatory mechanisms. We recently showed that lycopene can influence lymphocyte activity by modulating processes involved in early cellular activation. T lymphocytes comprise different subsets, T cytotoxic, T helper 1 (Th1), T helper 2 (Th2) and T regulatory cells (Treg). We aimed to determine whether lycopene could specifically modulate T-cell subsets function and activity.

Peripheral blood mononuclear cells from 11 healthy adults were cultured for 18hr to 60h in the presence of lycopene-enriched liposomes (0-1.18μg lycopene/ml) with or without mitogens. The secretion of cytokines representative of Th1,Th2 and Treg activities were measured by ELISA (IL-2, IL-1β, IL-10, IFN-γ and TGF-β) or cytometric bead array (IL-4, IL-10, IL17 and IFN-γ). The population profile of Tc (CD3+/CD8+), Th (CD3+/CD4+), Treg (CD4+/CD25+), and the Treg subsets nTreg (CD4+/CD25+/FoxP3+) and iTreg (CD4+/CD25+/IL-10+) was determined by flow cytometry.

After 18h incubation, IL-2 concentration in the medium was significantly reduced (-29%, p=0.001) in the presence of lycopene (1.18μg/mL). Similar effects were observed after 36h and 60h culture for IFN-γ (-23%, p=0.015), Il-10 (-30%, p=0.023), IL-17 (-30%, p=0.019) but not IL-4 or TGF-β. The proportion of Treg cell was also significantly increased by 36% (p=0.001) in the presence of lycopene (1.18μg/mL) compared with non-treated activated cells. Furthermore, the proportions of iTreg cells were significantly increased by after incubation with lycopene while the proportion of nTreg cells decreased (-20.5 %, p=0.049).

We conclude that increased lycopene intake may be beneficial against atherogenesis by modulating T lymphocyte function, particularly in relation toTh1 and Treg.
Abstract 436: Deregulation of Xbp1 Expression Contributes to Impaired Cardiac Vegf Expression and Angiogenesis During Progression From Cardiac Hypertrophy to Failure in vivo
Authors: Duan Quanlu , Chen Chen , Wang Peihua , Ni Li , Yang Lei , Wang Dao Wen
Published: July 2021

Background:
Increased angiogenic factor expression and enhanced coronary angiogenesis is an adaptive response to increased workload during cardiac hypertrophy. Disruption of coordinated tissue growth and cardiac angiogenesis in the heart contributes to the progression from adaptive cardiac hypertrophy to heart failure, but its molecular mechanisms remained unknown. The aim of the present study was to establish a role for the unfolded protein response (UPR) in the deregulation of proangiogenic factor VEGF expression and cardiac angiogenesis and potential regulatory mechanisms in hypertrophic and failing heart.

Methods and results:
Compared to normal control, VEGF-A expression was increased in failing human heart tissue and blood samples, which correlated with the levels of XBP-1, a key unfolded protein response (UPR) inducible transcription factor. Consistently, Western blots showed that cardiac expression of XBP-1 and VEGF-A were induced in the early adaptive phase, but decreased in the maladaptive phase in rat hypertrophic and failing heart. Similarly, Experiments in cultured cardiomyocytes H9c2 (2-1) cells showed that UPR-induced VEGF-A up regulation was determined by XBP-1 expression level. Furthermore, XBP1 was measured as a target of miR-30* by targeting 3′ UTR. Finally, we found that miR-30* was significantly reduced in the early phase of cardiac hypertrophic animal model and in human failing hearts but was increased in the maladaptive diseased heart.

Conclusion:
These results suggest that miR-30*/XBP1 regulates VEGF-mediated cardiac angiogenesis, which regulates the transition of adaptive hypertrophy into heart failure. This revealed miR-30*/XBP1/VEGF pathwagy might provide potential diagnosis value and novel targets for prevention and treatment of heart failure.
Abstract 444: Differential Contribution of Oxygenases in Glycerol-Induced Acute Renal Failure in the Rats
Authors: Newaz Mohammad
Published: July 2021

Oxidative stress has long been identified as one if the mechanism in glycerol-induced acute renal failure (ARF), a disease model of human rhabdomyolysis. Besides NAD(P)H Oxidase, cyclooxygenase (COX) and xanthine oxidase (XO) are important oxygenase system that contributes in free radical generation in the biological system. In this study we explore involvement of these oxygenase system as the source of free radical in ARF and investigate the relationship between NAD(P)H oxidase, COX and XO in this process. Renal failure was induced in male Sprague Dawley rats by injecting glycerol (8 ml / kg; 50% v/v; i.m) with or without pretreatment of apocynin (Apo: mg/kg in drinking water, 7 days) a NAD(P)H Oxidase inhibitor. Rats were sacrificed 24 hrs after inducing ARF and kidney tissues were analyzed for biochemical assays. Glycerol increased free radical production by 39% as evident by elevated 8-isoprostane. Inhibition of NAD(P)H oxidase by apocynin reduced free radicals by 46%. In ARF rats, NAD(P)H oxidase, COX and XO activities were elevated by 106%, 70%, and 208%, respectively. Apocynin prevented this attenuation of NAD(P)H oxidase (54%; p<0.05) and COX (62%; p<0.05) but did not alter XO activity. These data suggests that NAD(P)H oxidase, COX, and XO are involved in generating oxidative stress in ARF. We also propose that COX-mediated free radical generation requires a functional NAD(P)H oxidase.
Abstract 451: Oxygen Regulation of Human Coronary Artery Smooth Muscle Cell Proliferation and Migration
Authors: Yang Mingming , Kamishima Tomoko , Dart Caroline , Quayle John M
Published: July 2021

Introduction:
Intimal thickening of blood vessels, a hallmark of several vascular diseases including atherosclerosis and a potential point of therapeutic intervention, is caused by vascular smooth muscle cell proliferation and migration. It has been suggested that oxygen availability in vessels not only regulates behavior of smooth muscle cells but also serves as a trigger that may lead to pathological responses. In this study we determined whether hypoxia elicits proliferative and migratory responses in Human Coronary Artery SMCs (HCASMCs).

Methods:
Proliferation of HCASMCs was assessed using a 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. SMCs were plated in 96-well plates (n=5), serum starved, and then placed under hypoxic or normoxic conditions for 2, 4 and 6 days (2D/4D/6D) before MTT was added to each well. Absorbance at the wavelength 570 nm was read on an ELISA plate reader, and percent change in cell viability was determined and normalized to control (cell viability under normoxia). Cell migration was characterized by scratch-wound assay. SMCs were seeded in 6 well plates overnight (n=3), then a ‘scratch’ on the cell monolayer was created for each well before putting into different oxygen levels for 4 hours, 12 hours and 24 hours. Images were captured at the beginning and at intervals during cell migration to close the scratch, and the degree of migration was determined by comparing the images.

Results:
Compared to normoxic condition, cell number changed to 118.1%±1.3% in 5% O
2
(p<0.05) and 98.2%%±1.9% in 1% O
2
after 2D; to 151.9% ±8.5% in 5% O
2
(p<0.001) and 119.4%±5.0% in 1% O
2
(p<0.05) after 4D; and to 163.0%±4.3% in 5% O
2
(p<0.001) and 120.3%±2.2% in 1% O
2
(p<0.05) after 6D. In the cell migration assay, the difference in migration rate between different groups after 4 hours was not obvious, but there was a significant difference after 12 hours (29.3%±1.3% closure in normoxia vs 39.8%±1.9% in 5% O
2
vs 40.9%±3.5% in 1% O
2
, p<0.05) and 24 hours (71.5%±4.4% in normoxia vs 87.2%±2.2% in 5% O
2
vs 87.5%±3.1% in 1% O
2
, p<0.05).

Conclusion:
Our studies reveal that hypoxia induces both proliferation and migration of HCASMCs.
Abstract 452: Hyperglycemia and Oxidative Stress Impair Fluid Shear Stress-mediated Endothelial Nitric Oxide Synthase Phosphorylation and Activation via Disrupting Adherens Junctions
Authors: Yin Meimei , Xu Suowen , Wong Chelsea , Mastrangelo Michael A , Jin Zheng-Gen
Published: July 2021

Endothelial dysfunction, characterized by a decrease of nitric oxide (NO) bioavailability in the vessel wall, plays a crucial role in the pathogenesis of atherosclerosis. Oxidative stress due to increased reactive oxygen species (ROS) is implicated in endothelial dysfunction associated with diabetes. However the molecular mechanisms by which oxidative stress causes endothelial dysfunction remain incompletely understood. Blood flow, which generates fluid shear stress acting on endothelium, is the most potent physiological stimulus for NO production through endothelial NO synthase (eNOS) activation. Here we report that hyperglycemia and oxidative stress impairs fluid shear stress signal transduction and eNOS activation in endothelium. We found that the exposure of endothelial cells (ECs) to ROS generators such as menadione and xanthine/xanthine oxidase inhibited laminar flow-mediated Akt and eNOS phosphorylation and activation in human endothelial cells. Moreover, ECs pre-exposed to high glucose that generates ROS production in ECs, failed to respond to laminar flow for Akt/eNOS phosphorylation and activation. Consequently NO production from ECs in response to laminar flow was attenuated by high glucose treatment. Mechanistically, we observed that hyperglycemia and oxidative stress altered endothelial adherens junction integrity, manifested by the alternation of the localization of cell-cell junction molecules vascular endothelial cadherin (VE-cadherin) and beta-catenin. Silencing VE-cadherin or beta-catenin with small interference RNA also inhibited laminar flow-mediated signaling for eNOS activation, which mimics the effects of oxidative stress, suggesting that cell-cell junction integrity is critical for fluid shear stress signal transduction and eNOS activation. Collectively, our results demonstrate that hyperglycemia and oxidative stress impair laminar flow-mediated eNOS activation through the alternation of endothelial junction integrity and fluid shear stress signal transduction. Our findings suggest a novel mechanism whereby oxidative stress induces diabetes-associated endothelial dysfunction.
Abstract 455: Systemic, But Not Smooth Muscle Cell-Specific, TGF-β Blockade Exacerbates Angiotensin II-Induced Abdominal Aortic Pathology
Authors: Angelov Stoyan N , Hu Jie H , Airhart Nathan , Jaffe Mia , Du Liang , Dichek David A
Published: July 2021

Objectives:
The role of TGF-β signaling in adult vascular homeostasis and aortic aneurysm formation is controversial. Some studies report an association between aneurysm formation and evidence of increased TGF-β signaling in the aortic media; other studies report that TGF-β signaling is critical for adult aortic homeostasis and protects against aortic aneurysm growth. Data supporting a protective effect of TGF-β signaling were reported in the mouse model of Ang II-induced abdominal aortic aneurysm (AAA). However, it is unclear whether this protection is conferred by systemic or SMC-specific actions of TGF-β. Based on data that emphasize a salutary role for TGF-β signaling in SMCs,
we hypothesized
that TGF-β signaling protects the adult aorta from Ang II-induced AAA by actions on medial SMC.

Methods:
We compared the incidence and severity of AAA among 3 groups of Ang II-infused mice (4 wk infusion of 1000 ng/kg/min; n = 25/group). Groups included: 1) no TGF-β signaling blockade (control); 2) systemic antibody-mediated TGF-β blockade; and 3) SMC-specific blockade of TGF-β signaling (using inducible SMC-specific Cre recombinase).

Results:
Mice with systemic TGF-β signaling blockade, but not mice with SMC-specific TGF-β blockade, had larger maximal abdominal aortic diameters than control mice [Control = 1.3 ± 0.1 mm, Systemic = 1.8 ± 0.2mm, SMC-specific = 1.2 ± 0.03 mm; p = 0.01 (Systemic vs Control) and p = 0.5 (SMC-specific vs Control)], increased prevalence of aortic pathology [Control = 42%, Systemic = 78%, SMC-specific = 36%; p = 0.02 (Systemic vs Control) and p = 0.9 (SMC-specific vs Control)] and more severe aortic pathology [median severity scores on 0 [[Unable to Display Character: –]] 4 scale: Control = 0, Systemic = 2, SMC-specific = 0; p = 0.06 (Systemic vs Control) and p = 0.5 (SMC-specific vs Control)]. The differences in aortic diameter and pathology could not be attributed to differences in BP, which did not differ among the groups [Control: SBP = 125 ± 4, MAP = 104 ± 4; Systemic: SBP = 128 ± 6, MAP = 105 ± 5, SMC-specific: SBP = 116 ± 6, MAP = 103 ± 8; p = 0.6 (Control vs Systemic) and p = 0.3 (Control vs SMC-specific)].

Conclusions:
We confirm a protective effect of TGF-β signaling in the Ang II model of AAA and conclude that TGFβ signaling prevents aortic damage and dilation by actions outside the aortic media.
Abstract 459: Surgery for Small Asymptomatic Abdominal Aortic Aneurysms
Authors: Filardo Giovanni , Powell Janet T , Martinez Melissa A , Ballard David J
Published: July 2021

Background:
Treatment of asymptomatic abdominal aortic aneurysms (AAAs) heavily depends on the size of the aneurysm. Large asymptomatic AAAs (diameter >5.5cm) are usually repaired surgically; very small AAAs (diameter <4.0cm) are monitored. Debate continues over the appropriate management for AAAs of 4.0-5.5cm diameter.

Methods:
The Cochrane Specialised Register and the CENTRAL databases were searched for randomized controlled trials in which patients with asymptomatic AAAs of 4.0-5.5cm were randomized to immediate repair or imaging-based surveillance at least every 6months. Outcomes had to include mortality/survival. Data were independently extracted by three researchers and were cross-checked.

Results:
Four trials (3314 patients) fulfilled the inclusion criteria. Two trials compared surveillance with early open repair and two trials compared surveillance with early endovascular repair (EVAR). The four trials showed an early survival benefit in the surveillance group (due to 30-day surgery operative mortality) but no significant differences in long-term survival (HR=0.88; 95%CI: 0.75, 1.02, mean follow up [FUP] 10yrs; HR=1.21, 95%CI: 0.95, 1.54, mean FUP 4.9yrs; HR=0.76, 95%CI: 0.30, 1.93, mean FUP 3yrs; HR=1.01, 95%CI: 0.49, 2.07, mean FUP 20months). A pooled analysis of patient-level data from two trials (6yrs FUP) showed no statistically significant survival difference between early open repair and surveillance (propensity-score adjusted HR=0.99; 95%CI: 0.83, 1.18), and that this lack of treatment effect did not vary by AAA diameter (P=0.39) or patient age (P=0.61). The meta-analysis of mortality at one year for EVAR trials likewise showed no significant association (RR at one year 1.15, 95%CI: 0.60, 2.17).

Conclusions:
The results from the four trials to date demonstrate no advantage to early repair for small AAA, regardless of whether open repair or EVAR is used and, at least for open repair, regardless of patient age and AAA diameter.
Abstract 46: Cellular Cholesterol Homeostasis is Altered in Murine Models of Rheumatoid Arthritis and is Linked to Enhanced Myelopoiesis
Authors: Dragoljevic Dragana , Kraakman Michael J , Ngo Devi , Whillas Alexandra , van Doornum Sharon , Wicks Ian , Febbraio Mark A , Chin-Dusting Jaye P , Murphy Andrew J
Published: July 2021

Rheumatoid arthritis (RA) is associated with a ~2-fold elevated risk of morbidity and mortality from atherosclerotic cardiovascular disease (CVD) compared with the general population. Atherosclerosis in RA patients tends to be more aggressive and therefore more challenging to treat. Identifying CVD in these patients is difficult as traditional CVD risk factors, such as changes in plasma lipid profiles (i.e. elevated LDL, decreased HDL) are not always observed, underscoring the need for better understanding of the reasons contributing to the enhanced atherosclerosis in RA patients. People with RA often have monocytosis and neutrophilia, which we hypothesize to plays causal roles in atherosclerosis. Two mouse models of RA were used, K/BxN serum transfer and collagen induced arthritis (CIA). Flow cytometry was used to quantify the abundance of leukocyte and stem cell subsets. BODIPY-cholesterol was employed to determine the membrane cholesterol status of the various cells. Prominent monocytosis and neutrophilia due to an expansion and increased proliferation of the haematopoietic stem and multipotential progenitor cells (HSPCs) in the bone marrow (BM) was observed in both models of RA. There was also an increase in the mobilisation of HSPCs into the circulation, which homed to the spleen, resulting in extramedullary haematopoiesis. Interestingly, key cholesterol efflux genes, Abca1, Abcg1 and Apoe were down regulated in the BM HSPCs isolated from the K/BxN mice, resulting in increased cell membrane cholesterol levels. We also observed an increase in the expression of the common beta subunit of the interlukin-3 receptor on the HSPCs and the M-CSF receptor in myeloid progenitor cells, likely explaining their increased proliferation and skewing to the myeloid lineage. Moreover, blood monocytes and neutrophils had increased membrane cholesterol content, independent of changes in plasma cholesterol levels. These data suggest that while plasma cholesterol levels may not be increased in RA, cellular cholesterol homeostasis might be increased. We hypothesize that this, together with enhanced monocyte production, underlies the increased risk of CVD in RA.
Abstract 461: Cilnidipine Attenuated Angiotensin II-induced Abdominal Aortic Aneurysms in Apolipoprotein E-deficient Mice
Authors: Kakio Yuki , Uchida Haruhito A , Umebayashi Ryoko , Wada Jun
Published: July 2021

Objective:
Chronic infusion of angiotensin II (AngII) promotes development of abdominal aortic aneurysms (AAAs) in hypercholesterolemic mice. Previous studies have shown that local inflammation and increased oxidative stress plays an important role on formation of AAAs. In addition, it is reported that voltage-dependent N-type Ca2+ channels in endothelial cells contribute to oxidative stress-related endothelial dysfunction induced by AngII in mice. Therefore, we hypothesized that cilnidipine, an N/L-type calcium channel blocker, exerts vasoprotective effect by inhibiting inflammation and superoxide generation in mice. The purpose of this study was to evaluate whether cilnidipine influenced AngII-induced AAAs.

Methods and Results:
Male apolipoprotein E deficient mice (8-12 weeks old) were fed a normal laboratory diet. Mice were infused subcutaneously with either cilnidipine or vehicle by osmotic minipumps. Three days later, mice were also infused subcutaneously with either AngII (1,000 ng/kg/min, n = 14-16) or saline (n = 4) each by osmotic minipumps for 4 weeks. AngII increased systolic blood pressure. Cilnidipine decreased blood pressure in AngII-infused mice, but had not effect during saline infusion. AngII infusion did not alter serum cholesterol concentrations. However, cilnidipine slightly decreased serumcholesterol concentrations in AngII-infused mice. Cilnidipine had no effect on body weights, heart rates, and urine total protein, but mildly restored plasma renin activity that were suppressed by AngII infusion. Cilnidipine did not affect ex vivo measurement of maximal diameter of abdominal aorta (1.04 ± 0.09 mm vs 1.11 ± 0.06 mm, n.s.) in saline infused mice. AngII infusion significantly increased ex vivo maximal diameters of abdominal aortas, but was attenuated by cilnidipine (1.79 ± 0.59 mm vs 1.26 ± 0.38 mm, P < 0.05). In addition, cilnidipine significantly reduced the incidence of AngII-induced AAAs (Cilnidipine: 38 %, Vehicle: 88 %; P < 0.05). Furthermore, gelatin zymography demonstrated that cilnidipine diminished AngII-induced increase in aortic MMP-9 protein abundance.

Conclusion:
Cilnidipine attenuated AngII-induced AAAs in male apolipoprotein E deficient mice.
Abstract 466: Metabolome Profile of Experimental Abdominal Aortic Abdominal Aneurysms
Authors: Wang Xin , Dalman Ronald L , Xuan Haojun , Fujimura Naoki , Deng Hongping , Iida Yasunori , Snyder Michael P , Xu Baohui
Published: July 2021

Abdominal aortic aneurysm (AAA) is a degenerative inflammatory disease involving multiple metabolic and signaling pathways. To date, no circulating biomarker accurately identifies AAAs in asymptomatic persons or predicts AAA progression or response to treatment following endovascular exclusion. This study sought to define the serum metabolome, the complete set of small molecule metabolites in experimental AAAs. Methods: AAAs were created via intra-aortic porcine pancreatic elastase (PPE) infusion in male C57BL/6J mice or 28-day subcutaneous infusion of angiotensin (Ang) II in male ApoE knockout (KO) mice. PBS was infused as the controls. Aortic diameter was measured via ultrasonography. Sera were prepared at sacrifice (14 (PPE) or 28 (Ang II) days following AAA initiation). Serum metabolites were identified via ultra performance liquid chromatography-mass spectrometry (UPLC-MS) and analyzed via O2PLS method using SIMCA software. Results: Substantial aortic enlargement occurred in C57BL/6J and ApoE KO mice following PPE and Ang II infusion compared to PBS-infused mice. In UPLC-MS assays, both O2PLS 2D and 3D score plots identified distinct metaboloic signatures between non-aneurysmal C57BL/6J and ApoE KO mice (PBS infusion). Further, 3D score plot differentiated aneurysmal (PPE or Ang II infusion) from non-aneurysmal metabolome in both PPE and Ang II infusion models. However, the 2D score plot failed to demonstrate the difference in the later model. Conclusion: Experimental AAA generates a characteristic metabolome, potentially providing pathogenetic clues as well as a convenient and reproducible biomarker for monitoring disease progression.
Abstract 476: Glucagon Like Peptide -1 Receptor Activation Does Not Affect Re-endothelialization But Reduces Intimal Hyperplasia via Direct Effects on Smooth Muscle Cells in a Non-diabetic Model of Arterial Injury
Authors: Eriksson Linnea , Saxelin Robert , Röhl Samuel , Roy Joy , Caidahl Kenneth , Nyström Thomas , Hedin Ulf , Razuvaev Anton
Published: July 2021

Background/Aims:
Diabetic patients have an increased risk of restenosis and late stent thrombosis after angioplasty, complications that are related to a defective re-endothelialization. Exendin-4, a stable GLP-1 receptor agonist has been suggested to influence the formation of intimal hyperplasia and to increase endothelial cell proliferation in vitro. Thus, the aim of the study was to investigate the mechanisms by which treatment with exendin-4 could influence re-endothelialization and intimal hyperplasia after vascular injury.

Methods:
40 male Sprague-Dawley rats were subjected to balloon injury of the left common carotid artery (LCCA) and treated for four weeks with exendin-4 (1 nmol/day) or vehicle. Intimal hyperplasia and vessel wall elasticity were monitored non-invasively by high frequency ultrasound and re-endothelialization was evaluated upon sacrifice using Evans blue dye. The LCCA was then sectioned for subsequent morphometric and immunohistochemical analyses. To further investigate if and how smooth muscle cells (SMCs) are directly affected by exendin-4 treatment, we studied proliferation and apoptosis of SMCs in vitro.

Results and Conclusion:
Exendin-4 selectively reduced proliferation of SMCs and intimal hyperplasia in vivo without affecting the re-endothelialization process, however treatment with exendin-4 improved arterial wall elasticity. Our data also show that exendin-4 significantly decreased the proliferation and increased the apoptosis of SMCs in vitro, effects that appear to be mediated through cAMP signaling and endothelial nitric oxide synthase following GLP-1 receptor activation. Together, these effects of exendin-4 are highly desirable and may lead to improved outcome for patients undergoing vascular interventions.
Abstract 478: FGF23 Expression in Cardiac Fibroblasts Is Augmented by S100/Calgranulins-Mediated Inflammation and Associated With Cardiac Hypertrophy, but Not in Angiotensin II-Induced Cardiac Hypertrophy
Authors: Hofmann Bowman Marion , Gardner Brandon , Earley Judy , Rateri Debra L , Daugherty Alan , Yan Ling
Published: July 2021

Background:
Serum S100A12 and fibroblast growth factor (FGF) 23 are biomarkers for cardiovascular mortality in patients with chronic kidney disease (CKD) and are associated with left ventricular hypertrophy (LVH). FGF23 is induced in cultured cardiac fibroblasts in response to cytokines including IL-6, TNF-a, LPS and S100/calgranulins. Moreover, hBAC-S100 transgenic mice with CKD had increased FGF23 in valvular interstitial cells and exhibited LVH. The present study was designed to examine cardiac FGF23 expression in other murine models of LVH in the absence of CKD.

Methods:
Hearts from five groups of male mice were studied: (i) C57BL6/J with transgenic expression a bacterial artificial chromosome of the human S100/calgranulins (S1008/9 and S100A12, hBAC-S100), (ii) wild type littermates, (iii) LDLR-/- infused with saline (29 days, 0.9%), (iv) LDLR-/- infused with angiotensin (Ang) II (29 days, 1000 ng/kg/min), and (v) fibroblast specific depletion of angiotensin II type 1a receptor (AT1aR) (S100A4-Cre x AT1aR-/- x LDLR-/-) infused with AngII.

Results:
hBAC-S100, but not wild type littermate mice, developed significant LVH at 10 months by heart weight/body weight (5.9 ±1.1 mg/g vs. 4.2 ±0.8, p<0.04), decreased E/A ratio, and increased LVPW thickness, and associated with increased expression of FGF23 mRNA and protein in cardiac tissue lysates (2-4 fold increase). Similarly, Ang II induced significant LVH compared to saline infused LDLR-/- mice (6.1±1.3 vs. 3.6 ±0.9 mg/g, p<0.01), and associated with increased mRNA for hypertrophic genes (ANP, BNP, b-MHC, CTGF and Col1a1). However, there was no significant difference in FGF23 mRNA and protein between Ang II and saline infused mice. Cardiac hypertrophy was attenuated in AngII-infused mice with deficiency of AT1aR (S100A4-Cre+/-xAT1aRxLDLR-/-). In vitro, Ang II (100nM) did not induce FGF23 in valvular interstitial fibroblasts or myocytes.

Summary:
Transgenic expression of S100/calgranulins is sufficient to induce LVH in aged mice with normal renal function, and this is associated with FGF23 expression in cardiac interstitial fibroblasts. Future studies are needed to determine whether cardiac FGF23 promotes LVH in a paracrine manner. However, FGF23 does not play a role in Ang II-induced LVH.
Abstract 480: Exacerbation of Arterial Stiffness in Obese Adiponectin Deficient Mice
Authors: Murali Megha , Taylor Carla , Zahradka Peter , Wigle Jeffrey
Published: July 2021

Background and Objective:
Arterial stiffness is recognized as being an independent predictor of incipient vascular disease associated with obesity and metabolic syndrome. In obese subjects, the decrease in the plasma level of adiponectin, an anti-diabetic and anti-atherogenic adipokine, is well known. Hence the aim of our study was to examine the effect of loss of adiponectin on the development of arterial stiffness in response to a high fat diet.

Methods and Results:
Male 8-week old adiponectin knockout (APN KO) and C57BL/6 (control) mice were fed a high fat diet (60% Calories from fat) for 12 weeks to induce obesity and insulin resistance (n=10/group). APN KO and C57BL/6 mice were fed a low fat diet (10% Calories from fat) and used as lean controls (n=10/group). After 12 weeks on the high fat diet, the APN KO mice weighed significantly more than the C57BL/6 mice (45.1±1.3 g vs 40.1±1.1 g, p=0.0008) but there was no difference in the final weights between genotypes fed the low fat diet. APN KO mice on both high and low fat diets for 12 weeks developed insulin resistance as measured by oral glucose tolerance test (Area under curve (AUC) mmol/L х min = 437±70 and 438±57) as compared to the C57BL/6 mice fed low or high fat diets (AUC mmol/L х min = 251±27 and 245±43). Arterial stiffness was determined by Doppler pulse wave velocity analysis of the femoral artery. Pulse wave velocity was increased in APN KO mice fed a high fat diet relative to those fed the low fat diet (12.56±0.78 cm/s vs 9.47±0.95 cm/s, p=0.0035; n=8-10). Pulse wave velocity was not different between C57BL/6 control mice on the low or high fat diets (10.63±0.73 cm/s and 10.86±0.50 cm/s), thus revealing that only mice deficient in adiponectin developed arterial stiffness in response to high fat diet.

Conclusions:
Potentiation of the vascular stiffness in diet-induced obese APN KO mice indicates that adiponectin has a role in modulating vascular structure and the APN KO mouse models the vascular changes that occur in human obesity and metabolic disorders. Morphometric analysis of the aortic tissues for vessel thickness and expression of extracellular proteins will further validate the potential role of adiponectin on the maintenance of arterial elasticity in addition to its known effect on eNOS mediated vasoprotection.
Abstract 50: A Phase I Clinical Trial Evaluating the Safety of With Allogeneic Adipose Tissue-derived Multilineage Progenitor Cells-transplantation Therapy in Homozygous Familial Hypercholesterolemia Patients
Authors: Koseki Masahiro , Yamashita Shizuya
Published: July 2021

Familial hypercholesterolemia (FH) is an inherited disorder, mainly caused by defects in low-density lipoprotein (LDL) receptor gene. The patients are characterized by high LDL cholesterol levels in the blood and premature cardiovascular disease. Although most of heterozygous FH patients are usually treated with statin, ezetimibe and bile acid sequestrants, homozygous FH patients are resistant to drug therapy. Therefore, in Japan, many of homozygous FH patients are treated by LDL-apheresis. LDL-apheresis is a great procedure to remove LDL cholesterol from the blood and contribute to improve prognosis of homozygous FH patients. However, the effect of removing LDL cholesterol is temporary and still not enough. As a definitive therapy, liver transplantation therapy could be one of options to recover LDL receptor, but donor is limited in Japan.

Therefore, based on the increase of the evidence about the safety of mesenchymal stem cells and percutaneous transhepatic portal approach in islet transplantation, we have developed a cell transplantation therapy with allogeneic adipose tissue-derived multilineage progenitor cells (ADMPCs), as an alternative treatment instead of liver transplantation.

Our group has already proved that xenogenic transplantation of human ADMPCs into Watanabe heritable hyperlipidemic rabbits resulted in significant reductions in total cholesterol, and the reductions were observed within 4 weeks and maintained for 12 weeks. These results suggested that hADMPC transplantation could correct the metabolic defects and be a novel therapy for inherited liver diseases.

Here, we report a protocol for the first-in-human clinical trial, which has been approved by the institutional review board and Ministry of Health, Labour and Welfare, Japan.
Abstract 501: Irregular Distribution and Accumulation of Desmin in Gastrocnemius Myofibers in Association With Abnormal Myofiber Morphology and Impaired Limb Function in a Mouse Model of Chronic, Hindlimb Ischemia
Authors: Koutakis Panagiotis , Swanson Stanley A , Zhu Zhen , Papoutsi Evlampia , Miserlis Dimitrios , Kim Julian Kyung-Soo , Pipinos Iraklis I , Casale George P
Published: July 2021

A myopathy characterized by myofiber degeneration and impaired limb function is present in the legs of patients with peripheral artery disease (PAD). A characteristic of myofibers in PAD legs is abnormal distribution and accumulation of desmin, a key protein of the myofiber cytoskeleton. Using a mouse model of chronic hindlimb ischemia, we investigated the effects of chronic inflow arterial occlusion on myofiber morphology and desmin expression in the gastrocnemius, in relation to limb function. Hindlimb ischemia was induced by staged ligation/division of the common femoral and iliac arteries of C57BL/6 mice and muscles were harvested 12 weeks later. Desmin expression was analyzed by quantitative fluorescence microscopy of slide-mounted gastrocnemius specimens and by Western Blot analysis of gastrocnemius lysates of 10 ischemic and 10 control mice. Gastrocnemius myofiber morphometrics were determined by fluorescence microscopy and limb muscle endurance was measured with a RotaRod apparatus. Desmin was significantly increased both in myofibers and in lysates of ischemic muscle compared to control muscle (+35%, p<0.001; +79%, p<0.01 respectively). Increased abundance was associated with a loss of organization of the protein, indicating damage to the cytoskeleton of the ischemic myofibers. These changes in desmin correlated with decreased cross-sectional area and solidity and increased roundness of the myofibers (p<0.01) and reduced limb muscle endurance (p <0.01). Using a mouse model of hindlimb ischemia, we have demonstrated that inflow arterial occlusion, produces a myopathy with abnormal distribution and accumulation of desmin, abnormal myofiber morphology and reduced limb muscle endurance, recapitulating the muscle pathology of PAD patients.
Abstract 506: Changes in Vascular Function from Pre-conception to Post-partum Among Mongolian Women
Authors: Davaasambuu Enkhmaa , Shufelt Chrisandra , Stuart Jennifer , Bairey Merz Noel , Fitzmaurice Garrett , Rich-Edwards Janet
Published: July 2021

Background:
A recent study found significant changes in maternal cardiovascular function from pre-conception to post-partum in British women.

Objective:
To document vascular function before, during, and after pregnancy as measured by brachial blood pressure, heart rate-corrected augmentation index (AIx75), and pulse wave velocity (PWV) in Mongolian women.

Methods:
70 women, planning to conceive, were enrolled in this prospective, longitudinal study. Within six months, 46 women conceived, 38 of whom delivered; of these, 27 with complete measurements were included in this analysis. Pre-conception, second trimester, third trimester, and 2 month post-partum vascular function were assessed using SphygmoCor arterial tonometry (Atcor Medical). Within-woman differences across time points, adjusted for age, parity and body mass index (BMI), were analyzed by repeated measures analysis of covariance.

Results:
Mean age was 31.3 ± 5.5 (SD) years, mean BMI was 21.9 ± 2.9 kg/m
2
and 81.5% were parous. We observed statistically significant differences across time points for AIx75 (p=0.02), with lowest levels in the second trimester and highest levels post-partum (Table). Brachial systolic and diastolic blood pressures and PWV were also lowest in the second trimester, but differences across time points were not statistically significant.

Conclusion:
In this pre-conception cohort followed through post-partum, we observed a significant, temporary decrease in AIx75 in pregnancy. The decrease in AIx75 represents increased vascular compliance necessary to accommodate the maternal physiologic and metabolic changes during pregnancy.