bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiation Safety and Electrophysiologists: Radiation Protection Status – Go for Zero Fluoroscopy European Heart Rhythm Association Registry
Authors: Krzowski Bartosz , Gawałko Monika , Peller Michał , Lodziński Piotr , Grabowski Marcin , De Potter Tom , Fiedler Lukas , Ernst Sabine , Duncker David , Chudzik Michał , Garcia Rodrigue , Russo Vincenzo , Yakushev Andriy , Kosiuk Jedrzej , Balsam Paweł
Published: July 2021

Background: The purpose of this study was to analyze electrophysiologists’ radiation-protective devices for occupational exposure across European countries. Methods: Data reported herein were gathered from the international, multicenter prospective Go for Zero Fluoroscopy registry performed in years 2018–2019. The registry encompassed 25 European electrophysiological centers from 14 countries and up to 5 operators from each center. Results: The analysis included 95 operators (median age: 39 years, 85% of male, median training time: 5 years). The most frequently used X-ray protection tools (used by ≥80% of the group) were lead aprons, thyroid shields, screens below the table, glass in the laboratory, and least often (<7%) protective gloves and cabin. No statistically significant differences regarding the number of procedures performed monthly, electrophysiologists’ experience and gender, and radiation exposure dose or radiation protection tools were observed, except lead thyroid shields and eyeglasses, which were more often used in case of fewer electrophysiological procedures performed (<20 procedures per month). Operators who were protected by >4 X-ray protection tools were exposed to lower radiation levels than those who were protected by ≤4 X-ray protection tools (median radiation exposure: 0.6 [0.2–1.1] vs. 0.2 [0.1–0.2] mSv per month, p < 0.0001; 1.1 [0.1–12.0] vs. 0.5 [0.1–1.1] mSv per year, p < 0.0001), respectively. Conclusions: Electrophysiologists’ radiation-protective devices for occupational exposure are similar across European centers and in accordance with the applicable X-ray protection protocols, irrespective of the level of experience, number of monthly performed EP procedures, and gender.
High Failure Rate After Valve-sparing Aortic Root Replacement Using the “Remodeling Technique” in Acute Type A Aortic Dissection
Authors: Leyh Rainer G. , Fischer Stefan , Kallenbach Klaus , Kofidis Theo , Pethig Klaus , Harringer Wolfgang , Haverich Axel
Published: July 2021

Background

Valve-sparing surgery including the replacement of the sinus of valsalvae were initially meant to be promising approaches in the treatment of acute type A aortic dissection. However, the long-term outcome after valve-sparing aortic root replacement in acute type A dissection is currently the subject of intense debate, and the evidence reported in the literature is sparse. Here we report on our experience on valve sparing aortic root replacement inpatients with acute type A dissection.

Methods

From August 1995 to November 2000, 30 patients with acute type A dissection received valve-sparing aortic root replacement. Two different techniques were performed: the “remodeling” technique, first described by Yacoub in 1983 (8 patients) and the “reimplantation” technique, initially described by David and Feindel, in 1992 (22 patients). Endpoints of the study were early and late mortality, as well as aortic valve-related complications and reoperations.

Results

The mean follow-up time was 22.6±15.4 months. The overall 30 day mortality was 17% (5/29) and the late mortality 4% (1/24). During the observation period, 4 patients had to be reoperated (n=3) for acute aortic valve regurgitation after aortic root remodeling and for acute aortic valve endocarditis (n=1) after aortic root reimplantation. In the 3 patients with acute aortic valve regurgitation, symptoms occurred 44, 24, and 17 months after the initial operation in these patients. Intraoperatively prolapsing aortic leaflets because of commissural detachment was found in all 3 cases. In all other patients the latest echocardiographic follow-up examination revealed freedom from aortic regugitation higher than grade 1.

Conclusions

The high failure rate of aortic root remodeling inpatients with acute type A aortic dissection is discouraging. Whether this technique should be applied in acute type A aortic dissection is questionable. In contrast, aortic root reimplantation lead to favorable midterm outcome. Thus, we recommend consideration of this technique for surgical treatment of patients with acute type A aortic dissection.
Dopamine Treatment of Postischemic Contractile Dysfunction Rapidly Induces Calcium-Dependent Pro-Apoptotic Signaling
Authors: Stamm Christof , Friehs Ingeborg , Cowan Douglas B. , Cao-Danh Hung , Choi Yeong-Hoon , Duebener Lennart F. , McGowan Francis X. , del Nido Pedro J.
Published: July 2021

Background

Ischemia and adrenergic stimulation of cardiomyocyte cultures have been shown to induce apoptotic cell death. We hypothesized that in a model of contractile dysfunction following ischemia, a commonly used catecholamine such as dopamine augments cardiomyocyte apoptosis via activation of calcium-dependent signaling cascades.

Methods and Results

Isolated perfused rabbit hearts were subjected to 45 minutes of normothermic ischemia with cardioplegic arrest. Hearts were reperfused for 120 minutes with unmodified perfusate (control), perfusate containing 20 nM dopamine, dopamine+2,3-butanedione monoxime (BDM), a MgATPase-inhibitor, or the calcium-sensitizing inotrope ORG 30029. Ischemia-reperfusion alone caused contractile dysfunction without significant myocardial necrosis (left ventricular pressure-volume curves; 1% triphenyltetrazolium chloride staining; creatine kinase release) or apoptosis (terminal deoxynucleotidyl transferase-mediated nick end labeling [TUNEL] analysis; immunoblotting for poly(ADP-ribose) polymerase [PARP] cleavage; activation of caspases-3, -8, and -9; expression of Bax/Bcl-2). Intracellular calcium [Ca
2+
]

i

measured by rhod-2 spectrofluorometry was increased in dopamine-reperfused hearts. Although postischemic dopamine treatment improved contractility, the number of apoptotic cardiomyocytes was significantly higher than in untreated postischemic hearts (32.5±9 versus 5.5±1.6/1000 nuclei,
P
<0.01). Further evidence of dopamine-stimulated apoptosis included PARP cleavage, activation of mitochondrial-derived caspase-9, and the terminal effector caspase-3. Dopamine also increased cellular content of pro-apoptotic Bax while decreasing anti-apoptotic Bcl-2. Simultaneous treatment with BDM suppressed contractility without affecting [Ca
2+
]

i

and did not reduce dopamine-stimulated apoptotic markers. When contractility was increased without elevating [Ca
2+
]

i

using ORG 30029, no activation of pro-apoptotic signaling cascades was found. Dopamine infusion in nonischemic hearts did not result in cardiomyocyte apoptosis.

Conclusions

Postischemic dopamine treatment of contractile dysfunction activates pro-apoptotic signal cascades, most likely via a calcium-dependent process and mitochondrial damage.
Method of Cell Transplantation Promoting the Organization of Intraarterial Thrombus
Authors: Hirano Koji , Shimono Takatsugu , Imanaka-Yoshida Kyoko , Miyamoto Keiichi , Fujinaga Kazuya , Kajimoto Masaki , Miyake Yoichiro , Nishikawa Masakatsu , Yoshida Toshimichi , Uchida Atsumasa , Shimpo Hideto , Yada Isao , Hirata Hitoshi
Published: July 2021

Background—

Endovascular aortic repairs have been developed as less invasive treatments for aortic aneurysms. Some aneurismal cavities, however, remain without organization, causing a re-expansion of the aneurysms. We studied cell transplantation into the aneurismal sac to promote the organization of thrombus for the complete healing of aneurysms.

Methods and Results—

Skin fibroblasts and skeletal myoblasts were isolated from rats for cell transplantation. An intraarterial thrombus model was made by ligation of the carotid artery. Culture medium (medium group, n=11), collagen gel (gel group, n=11), fibroblasts with collagen gel (F group, n=15), myoblasts with collagen gel (M group, n=12), or mixture of fibroblasts and myoblasts with collagen gel (F+M group, n=14) were injected into the thrombus. After 28 days, histologically, the arterial lumens of the F and M groups were partly filled with fibrous tissues, whereas in the F+M group organization was almost completed and luminal sizes diminished. Immunohistochemical staining demonstrated that α-smooth muscle actin-positive cells were more abundantly contained in the organized area of the F+M group than in the other groups. We also analyzed cellular function in vitro with immunofluorescence; coculture of fibroblasts and myoblasts showed that the fraction of α-smooth muscle actin-positive fibroblasts increased. This phenomenon accounts for the rapid organization of thrombus in the F+M group in vivo.

Conclusions—

Cell transplantation accelerated thrombus organization. Especially, myoblasts enhanced differentiation of fibroblasts into myofibroblasts, contributing to rapid thrombus organization. Cell transplantation into unorganized spaces seems applicable to endovascular treatment of aneurysms.
NOGA-Guided Analysis of Regional Myocardial Perfusion Abnormalities Treated With Intramyocardial Injections of Plasmid Encoding Vascular Endothelial Growth Factor A-165 in Patients With Chronic Myocardial Ischemia
Authors: Gyöngyösi Mariann , Khorsand Aliasghar , Zamini Sholeh , Sperker Wolfgang , Strehblow Christoph , Kastrup Jens , Jorgensen Eric , Hesse Birger , Tägil Kristina , Bøtker Hans Erik , Ruzyllo Witold , Teresiñska Anna , Dudek Dariusz , Hubalewska Alicja , Rück Andreas , Steen Nielsen Søren , Graf Senta , Mundigler Gerald , Novak Jacek , Sochor Heinz , Maurer Gerald , Glogar Dietmar , Sylven Christer
Published: July 2021

Background—

The aim of this substudy of the EUROINJECT-ONE double-blind randomized trial was to analyze changes in myocardial perfusion in NOGA-defined regions with intramyocardial injections of plasmid encoding plasmid human (ph)VEGF-A
165
using an elaborated transformation algorithm.

Methods and Results—

After randomization, 80 no-option patients received either active, phVEGF-A
165
(n=40), or placebo plasmid (n=40) percutaneously via NOGA-Myostar injections. The injected area (region of interest, ROI) was delineated as a best polygon by connecting of the injection points marked on NOGA polar maps. The ROI was projected onto the baseline and follow-up rest and stress polar maps of the 99m-Tc-sestamibi/tetrofosmin single-photon emission computed tomography scintigraphy calculating the extent and severity (expressed as the mean normalized tracer uptake) of the ROI automatically. The extents of the ROI were similar in the VEGF and placebo groups (19.4±4.2% versus 21.5±5.4% of entire myocardium). No differences were found between VEGF and placebo groups at baseline with regard to the perfusion defect severity (rest: 69±11.7% versus 68.7±13.3%; stress: 63±13.3% versus 62.6±13.6%; and reversibility: 6.0±7.7% versus 6.7±9.0%). At follow-up, a trend toward improvement in perfusion defect severity at stress was observed in VEGF group as compared with placebo (68.5±11.9% versus 62.5±13.5%,
P
=0.072) without reaching normal values. The reversibility of the ROI decreased significantly at follow-up in VEGF group as compared with the placebo group (1.2±9.0% versus 7.1±9.0%,
P
=0.016). Twenty-one patients in VEGF and 8 patients in placebo group (
P
<0.01) exhibited an improvement in tracer uptake during stress, defined as a ≥5% increase in the normalized tracer uptake of the ROI.

Conclusions—

Projection of the NOGA-guided injection area onto the single-photon emission computed tomography polar maps permits quantitative evaluation of myocardial perfusion in regions treated with angiogenic substances. Injections of phVEGF A
165
plasmid improve, but do not normalize, the stress-induced perfusion abnormalities.
Abstract 113: Glucose Metabolic Disorders in Aging-Associated Microglial NADPH Oxidase 2 Activation and Oxidative Damage of Cerebral Microvasculature and Neurons
Authors: Geng Li , Li Jian-Mei
Published: July 2021

Aging has been recognised to be a major risk factor for the development of cardiovascular and neurodegenerative diseases and growing evidence suggests a role for oxidative stress. A Nox2-containing NADPH oxidase has been reported to be a major source of reactive oxygen species (ROS) generation in the vascular system and in the brain. However, the role of Nox2 enzyme in aging-related metabolic disorders and vascular neurodegeneration remains unclear. In this study, we used age-matched wild-type (WT) and Nox2-deficient (Nox2
-/-
) mice on a C57BL/6 background at young (3-4 month) and aging (20-24 month) to investigate the role of Nox2 in aging-related oxidative stress, metabolic disorders and cerebral vascular dysfunction. There was an aging-related increase in blood pressure in WT mice (126 mmHg for young and 148 mmHg for aging) (P<0.05); however the blood pressure was well maintained without significant change in Nox2
-/-
aging mice. Compared to young WT mice, WT aging mice had significantly high levels of fasting serum insulin and this was accompanied with delayed clearance of glucose (P<0.05) indicating insulin resistance. In contrast, there was no indication of insulin resistance for Nox2
-/-
aging mice. We then examined aging-related brain oxidative stress. Compared to WT young mice, there were significant increases (2.7±0.7 folds) in the levels of ROS production by WT aging brain tissue homogenates as detected by lucigenin-chemiluminescence and DHE fluorescence. Increased ROS production in WT aging brain was accompanied by a significant increase (1.8±0.3 folds) in the Nox2 expression detected mainly in the microglial cells (labelled by Iba-1) and decreases in brain capillaries (labelled by CD31) (2.4±0.8 folds) and neurons (labelled by Neu-N) (2.9±0.5 folds) (all P<0.05). Knockout of Nox2 abolished aging-associated increases in brain ROS production and significantly reduced the aging-related pathophysiological changes in the brain. In conclusion, aging-associated metabolic disorders play a crucial role in aging-associated Nox2 activation and vascular neurodegeneration. Nox2-containing NADPH oxidase represents a valuable therapeutic target for oxidative stress-related brain microvascular damage and neurodegeneration.
Abstract 123: Perivascular Adiponectin Attenuates the Neointimal Response Potentially via Modulation of Hydrogen Sulfide
Authors: Trocha Kaspar , Tao Ming , Macarthur Michael , Longchamp Alban , Trevino Humberto , R. de Vries Margreet , Mitchell James , Ozaki C. Keith
Published: July 2021

Objective:
Intimal hyperplasia (IH) limits the durability of vascular interventions. Perivascular adipose serves as scaffolding for vessels and also as a source of adipokines, including adiponectin (APN). The globular domain of adiponectin (gAPN) has high affinity for endothelial AdipoR1 receptors and holds beneficial roles in vascular adaptations. Hydrogen sulfide (H
2
S) is a vasculo-protective gasotransmitter produced by cystathionine γ-lyase (CGL), and low circulating H
2
S levels associate with human vascular disease. We therefore hypothesized that APN knockout (KO) mice would be predisposed to IH, and that local administration of gAPN would protect APN KO mice from IH. Furthermore, we evaluated potential links between APN and H
2
S in these effects.

Approach and Results:
Wildtype (WT, n=7) and APN KO (n=8) mice maintained on high fat diet were subject to carotid focal stenosis. An additional group of APN KO mice (n=7) were treated by local injection of gAPN suspended in Matrigel. Carotids were harvested 28 days following surgery and analyzed 400-2800μm proximal to the stenosis microscopically. IH area was significantly increased at 400μm in APN KO mice compared to WT (p=<0.05, Fig. A), while gAPN significantly attenuated intimal area compared to untreated KO mice (p=<0.05, Fig. B). This finding was coupled with significant (p=<0.05, Fig. C) decrease in pre-operative baseline serum H
2
S production capacity in APN KO (lead acetate assay) compared to WT. Serum collected upon harvest trended toward increased H
2
S production capacity in APN KO mice treated with gAPN (Fig. D). Kidney CGL expression (Western) revealed a trend for increased in CGL expression in the gAPN group (Fig. E).

Conclusion:
In a focal stenosis model APN KO mice demonstrated increased distal IH; when administered locally, gAPN significantly attenuated IH. These data also uncover a reduction in H
2
S production capacity in APN KO mice, providing a novel potential link between these potent vasomediators.
Abstract 125: Association Between Abo Blood Group, Von Willebrand Factor and Factor VIII in Patients Undergoing Vascular Surgery
Authors: Ujueta Francisco , Nardi Michael A , Guo Yu , Perez Adriana , Rubin Maya , Adelman Mark , Rockman Caron B , Berger Jeffrey S
Published: July 2021

Background:
ABO blood groups have been associated with functional effects on factor VIII (FVIII), von Willebrand factor (vWF) and incident atherothrombosis. This study sought to examine the association between ABO blood type, FVIII and vWF in patients undergoing vascular surgery.

Method:
This is a retrospective analysis of data from a cohort of 181 patients undergoing elective vascular surgery. ABO blood type, FVIII and vWF was measured before surgery. The primary end point was the occurrence of MACE (defined as myocardial necrosis, myocardial infarction, stroke or death) within 30-days after surgery. Multivariable logistic regression modeling was used to estimate odds of MACE.

Results:
The mean age was 71.6 ± 9.8 and 29% were female. Non-O blood type was present in 105 patients (70 A, 27 B, 8 AB) and type O in 76 patients. Non-O had higher FVIII (128.2 ± 44.7 vs 112.4 ± 42.4, P<0.001) and vWF (176.0 ± 54.0 vs 133.2 ± 41.0, P<0.001) than type O. Thirty day MACE occurred in 38 (21.0%) patients; 25% in non-O and 15.8% in type O (P=0.13). After adjustment for age, sex, race, prior coronary artery disease and heart failure, patients with non-O blood type (vs. O) had a higher incidence of 30-day MACE (odds ratio 2.1, 95% CI 0.9 to 5.1, P=0.08) although statistical significance was not reached. There was no significant association between FVIII and vWF and 30-day MACE.

Conclusions:
Non-O blood type was associated with higher levels of FVIII and vWF and a trend towards increased 30-day MACE in patients undergoing vascular surgery. Larger studies across of ABO blood groups and perioperative events in different types of surgeries are warranted.
Abstract 127: Colchicine Attenuates Vein Wall Scarring in Murine Venous Thrombosis: Implications for Limiting the Post-Thrombotic Syndrome
Authors: Qi Guanming , Kessinger Chase W , Mauskapf Adam , Jhajj Harkamal S , Henke Peter , Jaffer Farouc A
Published: July 2021

Objective:
In this study, we investigated the effects of colchicine on vein wall inflammation and scarring, and thrombus burden/VT resolution, key drivers of the PTS.

Methods:
Inferior vena cava (IVC) stasis VT were created in C57BL/6 mice (n=60). Colchicine (0.2 or 0.02 mg/kg for high or low dose, respectively) was administered daily via intraperitoneal injection starting 24 hours after VT initiation. At VT timepoints of day 4, 8 and 14, mice were sacrificed and VT were resected for measurements of thrombus. Picrosirius-red staining of VT sections assessed vein wall thickness. Serial sections were processed for Carstairs fibrin staining and immunostaining. The number of vein wall fibroblasts and macrophages per 5 high-power fields (400х) were calculated.

Results:
Colchicine significantly decreased venous thrombus-induced vein wall scarring at Day 8 (PBS 71.53±6.97μm, Col lo 55.11±5.48μm, Col hi 46.84±2.03μm; n=5 per group; PBS vs Col lo, P < 0.01; Col lo vs Col hi, P < 0.05) and at Day 14 (PBS 55.29±8.97μm, Col lo 45.20±2.73μm, Col hi 42.68±3.57μm; n=4-7 per group; PBS vs Col lo, P < 0.05; PBS vs Col hi, P < 0.05; Col lo vs Col hi, P > 0.05). Colchicine reduced the number of vein wall F4/80+ macrophages (PBS vs Col hi, 73.33±8.63 vs 55.87±8.07, n=5 per group, P < 0.01) and FSP1+ cells (PBS vs Col hi, 73.80±8.01 vs 41.60±8.37, n=5 per group, P < 0.01) in DVT D8. Also, colchicine reduced RNA expression of both profibrotic (collagen I, collagen III, procollagen I, procollagen III, FSP1) and proinflammatory (IL-1β, CD68) markers in DVT D8 (n=8 per group, P < 0.05). Of note, despite possessing anti-inflammatory actions, colchicine did not impair VT resolution (measured by thrombus mass) at D4 PBS vs Col hi, 27.00±5.11 vs 23.47±6.03mg/cm, n=9-12 per group, P > 0.05) nor at D8 (PBS vs Col hi, 19.05±5.23 vs 15.58±6.52mg/cm, n=12 per group, P > 0.05).

Conclusion:
The FDA-approved agent colchicine reduces experimental VT-induced vein wall scarring without impairing thrombus resolution. Anti-scarring effects may be related to attenuated inflammation of fibrotic mediators in the vein wall and adherent thrombus. Colchicine may offer a clinically viable option to reduce the post-thrombotic syndrome induced by deep vein thrombosis.
Abstract 128: LRP1 Deletion in Smooth Muscle Cells of the Outer Aortic Media Promotes Angiotensin II-induced Thoracic Aortic Aneurysm
Authors: Sawada Hisashi , Rateri Debra L , Majesky Mark W , Daugherty Alan
Published: July 2021

Objective:
Low-density lipoprotein receptor-related protein 1 (LRP1) is a multifunctional protein that is linked to several vascular pathologies. LRP1 deletion in smooth muscle cells (SMCs) accelerates angiotensin II (AngII)-induced thoracic aortic aneurysm (TAA). In association with TAA formation, there is medial thickening that is characterized by a transmural gradient in which pathology progressively increases from lumen to adventitial aspect. We hypothesized that deletion of LRP1 in the outer medial layers of the proximal thoracic aorta has a pivotal role in the pathogenesis of TAA. The aim of this study was to determine whether LRP1 deletion in the outer media accelerates AngII-induced TAA formation.

Methods and Results:
SMCs in the outer media of the ascending aorta are derived from the second heart field, as demonstrated by lineage tracing studies using Cre under the control of Mef2c. Therefore, we used Mef2c-driven Cre to delete LRP1 in SMCs of the outer medial layers. Female LRP1 flox/flox mice were bred to male Mef2c-Cre1/0 mice to generate study mice. We first confirmed LRP1 deletion in Cre1/0 mice by both immunostaining and Western blot. LRP1 was expressed ubiquitously across smooth muscle cells of all aortic medial layers in Cre 0/0 mice. In mice expressing Mef2c-Cre, aortic LRP1 protein was detected only in SMCs of the inner laminar medial layers. Western blotting demonstrated LRP1 protein abundance in Cre expressing mice was reduced by 43%. Saline or AngII (1,000 ng/kg/min) was infused by subcutaneous osmotic pumps for 28 days into 12 - 14 week-old male Cre0/0 and 1/0 mice. As expected, systolic blood pressure increased similarly in both AngII-infused Cre 0/0 and 1/0 mice compared to saline-infused mice. Aortic rupture occurred within 3 to 10 days after AngII infusion in 17% of AngII-infused Cre 0/0 mice, while LRP1 deletion in Cre 1/0 mice increased aortic rupture to 27%. Aortic diameter in the survivors was significantly increased in Cre1/0 mice compared to Cre0/0 mice. Histologically, elastin fragmentation was detected in the aorta of AngII-infused Cre 0/0 mice and greater in Cre1/0 mice.

Conclusion:
LRP1 in second heart field-derived SMCs of the outer media may play a critical role in the pathogenesis of TAA.
Abstract 129: The Role of Mechanosensing and Fak Pathway in Acute Aortic Dissections in the

Myh11
R247c

Mouse Model
Authors: Wang Shanzhi , Kwartler Callie , Zhang Teddy , Peters Andrew , Milewicz Dianna
Published: July 2021

Thoracic aortic dissections (TAD) are a cause of premature deaths. The major risk factors for TAD are hypertension (HTN) and genetic variants. Here we used an engineered mouse model with a homozygous
Myh11
missense variant (

Myh11
R247C

) in the motor head of the smooth muscle myosin heavy chain to identify signaling pathways that lead to TAD.

Results:
The

Myh11
R247C

alteration decreases aortic contractility but does not cause aortic disease in mice. When hypertension is induced by feeding the mice L-NAME and a high salt diet, blood pressures were both significantly increased within 2 weeks in wildtype (WT) and mutant mice. About 20% of mutant mice (4/22) died within 2 weeks but none of the WT mice (0/13) died (p=0.1). Necropsy identified pericardial tamponade due to a retrograde dissection in the ascending aorta as the cause of death in the mutant mice. Electron microscopy analyses found abnormal formation of focal adhesions (FAs) in the mutant mice compared with WT, leading to greater distortion of FAs in the mutant mice when HTN was induced. RNA sequencing and pathway analysis of the

Myh11
R247C

aortas identified the FA signaling as the major pathway altered with HTN. Phosphorylated FAK was increased in

Myh11
R247C

aortas at baseline compared with WT, and increased further in

Myh11
R247C

aortas with HTN induction. To activate FA signaling, explanted smooth muscle cells (SMCs) were seeded on fibronectin-coated plates. Levels of phosphorylated regulatory light chain were dramatically increased in mutant SMCs compared with WT, presumably to compensate for the defective myosin motor. Apoptosis markers, Bid and Bax, were also increased. To determine if FAK signaling and elevated apoptosis were involved in aortic dissection in the mutant mice, either a FAK inhibitor (PF573228) or p53 inhibitor (pifithrin-α) were administered 7 days before and during HTN induction. Both treatments completely prevent dissection deaths (P=0.03 and 0.05). In contrast, when prosurvival pathways were inhibited using a tyrosine kinase inhibitor, imatinib, dissection deaths significantly increased (p=0.002).

Conclusion:
These data indicated aberrant mechanosensing through focal adhesions leading to increased apoptosis trigger aortic dissections in the

Myh11
R247C

mouse model.
Abstract 14: Characterization of the Oxidized Phospholipid Modification of Apolipoprotein(a) Kringle KIV10: Insights Into the Site of OxPC Addition
Authors: Scipione Corey A , DeWolfe Travis , Gauld James W , Boffa Michael B , Ravandi Amir , Koschinsky Marlys L
Published: July 2021

Elevated plasma levels of lipoprotein(a) (Lp(a)) are an independent and causal risk factor for coronary heart disease and aortic valve stenosis. Lp(a) consists of a low density lipoprotein (LDL)-like particle covalently linked to the unique glycoprotein apolipoprotein(a) (apo(a)). We have shown that apo(a) contains a covalent oxidized phosphocholine (oxPC) adduct on the KIV
10
domain, and that perturbation of the strong lysine binding site (LBS) in this kringle results in a lack of covalent oxPC addition. We have implicated this modification in proinflammatory processes, such as the ability of apo(a) to induce interleukin-8 expression in macrophages. Apo(a) from Old World monkeys and apes lacks covalent oxPC modification and contains mutations in KIV
10
, some of which impact the LBS. To identify the amino acids in human apo(a) that are covalently modified by oxPC, we mutagenized a KIV
10
KV di-kringle apo(a) that contains covalent oxPC modification. We mutated to alanine all residues that are either substituted in primate apo(a) or that can act as acceptors for covalent oxPC addition. The resulting variants were then subjected to immunoblotting analysis with E06, an IgM antibody that binds to oxPC, and assessment of lysine-binding ability using affinity chromatography. Mutation of His33 to Ala abolishes oxPC modification of apo(a) while retaining the lysine binding ability of KIV
10
. Thus, we have identified the long-sought location of the oxPC modification of apo(a). Molecular dynamic simulations of the oxPC-deficient mutant show no gross changes in the structure of KIV
10
, in contrast to mutations that abolish both lysine binding ability and oxPC addition that result in a collapsed lysine binding pocket. Using mass spectrometry, we have also identified noncovalently-associated oxPC present on apo(a). Interestingly, the abundance of these species appears to be reduced in the apo(a) variant containing a mutation in the strong lysine binding site in KIV
10
. Our findings allow the ability to assess the contributions to pathogenesis of the strong lysine binding site and oxPC modification of apo(a) kringle IV type 10 independently, and thus will enhance our understanding of the mechanisms by which Lp(a) contributes to atherothrombotic diseases.
Abstract 146: Deficiency of Cystathionine beta Synthase Alters Blood Brain Barrier Integrity and Exacerbates Cerebral Ischemia Reperfusion Injury in Mice
Authors: Gu Sean X , Sonkar Vijay , Kruger Warren D , Bottiglieri Teodoro , Lentz Steven R , Dayal Sanjana
Published: July 2021

Hyperhomocysteinemia is a risk factor for stroke; however the mechanisms by which elevated homocysteine leads to stroke are poorly defined. In a murine model of cystathionine beta synthase (CBS) deficiency, we investigated whether mild to severe elevation in plasma total homocysteine (tHcy) increases susceptibility to cerebral infarction and if this phenotype is associated with loss of blood brain barrier (BBB) integrity. We studied male
Cbs
-/- mice conditionally expressing a zinc-inducible mutated human
CBS
(I278T)
transgene along with
Cbs+/-
and
Cbs+/+
littermates at 10-14 weeks of age. The human transgene was allowed to express only until weaning to overcome the early mortality of
Cbs-/-
mice. Experimental stroke was induced with middle cerebral artery occlusion for one hour followed by 24 hours of reperfusion. TTC stained coronal sections were used to quantify the infarcted area. BBB integrity was assessed prior to injury using a standard Evan’s blue (EB) infusion method. Leakage of EB was quantified in brain homogenates and normalized to brain weight. Mild to severe increases in plasma tHcy were observed in
Cbs
+/- and
Cbs
-/- mice (6.1±0.3 and 309±18 μM, respectively) compared with
Cbs+/+
littermates (3.1±0.6 μM, P<0.01). Both
Cbs
+/- and
Cbs
-/- mice exhibited significant increases in infarct size following ischemia-reperfusion injury as compared to
Cbs+/+
mice (12.2±3% in
Cbs+/+
mice vs. 35.1±7.7% in
Cbs+/-
and 27.7±7.8% in
Cbs-/-
mice, P<0.05). A significant increase in EB extravasation was observed in
Cbs+/-
and
Cbs
-/- mice (3.8±0.8 and 4.8±0.2 μg/g, respectively) compared to
Cbs+/+
mice (1.7±0.4 μg/g, P<0.05). The similarity in extent of cerebral infarction observed in
Cbs+/-
and
Cbs-/-
mice suggests a threshold effect and that a mild increase in tHcy is enough to disrupt BBB integrity and produce a severe stroke phenotype in experimental murine models.
Abstract 160: Multiscale Entropy of Photoplethysmographic Pulse Amplitudes of Bilateral Fingertips Varies by Hand Dominance and Diabetes Status
Authors: Lin Gen-Min , Yang Chieh-Ming , Wu Hsien-Tsai
Published: July 2021

Objective:
Multiscale entropy (MSE) of photoplethysmographic (PPG) pulse amplitudes may reflect cardiovascular health. In addition, poor glycemic control and weak handgrip strength are related to microvascular dysfunction in diabetes. We hypothesized that MSE of PPG pulse amplitudes between dominant and non-dominant hand may differ by diabetes status.

Methods:
Of a middle-to-old aged and right hand-dominant population free of prior cardiovascular disease, we matched age, sex, and weight to select the unaffected (no type 2 diabetes, n =36), the well-controlled diabetes (HbA1c <8%, n =22), and the poorly-controlled diabetes (HbA1c ≥8%, n =22) groups. MSEs were calculated from simultaneous consecutive 1,500 resting PPG pulse amplitudes of bilateral index fingers. The small- and large-scale MSEs were defined as the average of scales 1 to 3 (MSE
1-3
) and scales 4 to 10 (MSE
4-10
), respectively. Intra- and inter-groups comparisons were performed by 1- and 2-sample t tests.

Results:
The inter- and intra-groups mean pulse amplitudes did not differ. In contrast, the pulse wave velocity was higher in the two diabetes groups, but was similar between two hands in each group. The dominant hand MSE
4-10
was lower in the poorly-controlled diabetes compared with the unaffected and well-controlled diabetes groups (1.25 vs. 1.52 and 1.49, p=0.001 and 0.017, respectively); whereas the non-dominant hand MSE
4-10
was lower in the well- and poorly-controlled diabetes groups than the unaffected (1.31 and 1.26 vs. 1.54, p=0.007 and 0.002 respectively). There was no intra-groups difference in MSE
4-10
, but a higher MSE
1-3
of dominant hand than that of non-dominant hand in the well-controlled diabetes (1.30 vs. 1.07, p=0.05).

Conclusion:
Diabetes status and hand activity are related to the MSE of PPG pulse amplitudes. The MSE indexes differed between two hands with euglycemia indicated that local physical inactivity might be an independent contributor to diabetic microvascular dysfunction.
Abstract 161: Diet-Induced Obesity Links to Breast Cancer Progression via LPA/PKD-1-CD36 Signaling Axis-Mediated Microvascular Remodeling
Authors: Yuan Ye , Dong Liuyi , Aguilera-Barrantes Irene , Chen Yiliang , Yuan Rong , Silverstein Roy , Ren Bin
Published: July 2021

Background:
Obesity increases breast cancer (BC) risk. However, the molecular links by which obesity promotes BC progression remain largely unknown. Lysophosphatidic acid (LPA) produced excessively in obesity is a lipid signaling mediator essential for vascular remodeling, angiogenesis and BC progression, in which protein kinase D1 (PKD-1) and angiogenic regulator CD36 play an important role.

Hypothesis:
Obesity promotes microvascular remodeling and angiogenesis for BC progression via LPA/PKD-1-CD36 signaling axis.

Methods:
The hypothesis was tested in tumor-associated endothelial cells (TAECs), BC cells and a diet-induced obesity (DIO) mouse model. Lentiviral transduction, qPCR, Western blotting and Halo pull-down assays, angiogenesis profiling and immunofluorescence and immunohistochemical assays were applied for analysis of gene and protein expression, and relevant signaling pathways. Seahorse Bioscience Extracellular Flux Analyzer was used to detect cellular mitochondrial respiration.

Results:
LPA/PKD-1-CD36 signaling was a
bona fide
BC promoter via stimulating microvascular remodeling in chronic DIO. ER
+
breast cancer grew faster and larger in the DIO mice than in the lean control, specifically accompanied by enhanced microvascular remodeling in a syngeneic ER
+
BC model. The expression of vascular endothelial cell growth receptor 2, and endothelial differentiation gene 2/LPA receptor 1 (Edg2/LPA
1
), and phospho-PKD-1 also increased, accompanied by CD36 downregulation in the tumor endothelium. TAECs exposed to LPA showed sustained nuclear PKD-1 phosphorylation, and elevated mRNA levels of ephrin B2, and reduced CD36 mRNA expression, along with increased proliferation, which was inhibited by a selective PKD inhibitor. Finally, LPA/PKD-1 signaling changed mitochondrial respiration in ECs and breast adenocarcinoma cells.

Conclusion:
These studies suggest that LPA/PKD-1-CD36 signaling axis links DIO to BC progression via stimulation of arteriolar remodeling of microvasculature in the tumor microenvironment. The axis-mediated changes in cellular metabolism may promote the microvascular remodeling process. Targeting this signaling axis could provide an additional novel therapeutic strategy against breast cancer.
Abstract 164: The Effects of Resveratrol Treatment on Vascular Function in Type 2 Diabetes Mellitus
Authors: Zhang Ji-Yao , Holbrook Monika , Inagaki Elika , Feng Bihua , Ko Dorae , Weisbrod Robert M , Bastin Reena , Stathos Margaret , Breton-Romero Rosa , Fetterman Jessica , Hamburg Naomi M
Published: July 2021

Patients with diabetes mellitus (DM) have abnormal vascular function characterized by premature aging and aortic stiffness. In animal models of metabolic disease, the plant-derived polyphenol, resveratrol, decreases arterial stiffness through SirT1 activation. Therefore, we hypothesized that resveratrol would improve vascular function and activate SirT1 in patients with DM. We performed a randomized, double-blind, placebo-controlled crossover study of resveratrol supplementation in 57 patients with DM (age 56±8 years, female 52%, African-American 67%, BMI 31.7±4.4 kg/m
2
). Patients consumed resveratrol 100 mg/d for 2 weeks followed by 300 mg/d for 2 weeks or a matched placebo containing no polyphenols with a two-week wash-out period between treatments. In the overall study group, there was a trend toward lower carotid-femoral pulse wave velocity (CFPWV) with resveratrol treatment (P=0.18). In a subset of patients with high arterial stiffness at baseline, resveratrol treatment lowered CFPWV without a change in systemic blood pressure consistent with reduced central aortic stiffness (Figure). Brachial artery flow-mediated dilation, reactive hyperemia, and pulse amplitude tonometry did not change. In a subset of 7 patients, we collected venous endothelial cells by J-wire biopsy and observed a trend toward increased SirT1 activity with resveratrol treatment. Our findings suggest that resveratrol supplementation may reverse arterial stiffening in patients with DM potentially through activation of endothelial SirT1 activity.
Abstract 169: A Non-Viral Functionalized Nanoparticle Based Hepatocyte-Targeting Cholesteryl Ester Hydrolase Gene Delivery Strategy for Potential Alleviation of Atherosclerosis
Authors: He Hongliang , Lancina Michael , Wang Jing , Korzun William , Yang Hu , Ghosh Shobha
Published: July 2021

Current atherosclerosis treatment strategies primarily focus on limiting further cholesteryl ester (CE) accumulation within the plaques by reducing plasma LDL-cholesterol levels (the primary source of plaque CE) using multiple strategies. No therapy is currently available to enhance the removal of CE, a crucial step to reduce the burden of existing disease. Increasing hepatic CE hydrolysis by adenovirus or transgene mediated over-expression of CE hydrolase (CEH) enhances final elimination of cholesterol from the body and is anti-atherosclerotic. In an effort to advance towards application of this anti-atherosclerotic strategy, in the present study we developed a non-viral hepatocyte-specific platform, namely, galactose-functionalized polyamidoamine (PAMAM) dendrimer G5.0 (Gal-G5) for delivery of CEH expression vector via the hepatocyte-specific asialoglycoprotein receptor (ASGPR). ASGPR is triggered by binding of galactose residues and facilitates receptor-mediated endocytosis of large molecules across the hepatocyte plasma membrane. The data presented herein show increased specific uptake of Gal-G5 by hepatocytes
in vitro
(See Figure, Panel A) and liver
in vivo
(Panel B). Gal-G5 mediated delivery of CEH expression vector upregulated CEH expression in hepatocytes (Panel C), led to increased intracellular hydrolysis of HDL-CE and subsequent conversion/secretion of released FC into bile acids (Panel D). Gal-G5 mediated increased CEH expression in the liver significantly increased the flux of FC from HDL-CE into bile (Panel E) as well as feces (Panel F). These data are consistent with adenovirus or transgene-mediated over-expression of CEH and are likely to be anti-atherogenic. In conclusion, the development of this relatively non-toxic and efficient liver-specific gene delivery platform is an encouraging step towards clinical translation of strategies to enhance hepatic processes involved in final elimination of cholesterol from the body.
Abstract 181: Insulin Receptor Signaling Regulates ApoA-I Secretion from Hepatocytes
Authors: Ji Ailing , Wang Xuebing , Bennett Lisa , Graf David B , Graf Gregory A , van der Westhuyzen Deneys R
Published: July 2021

The aim of the study was to assess the effect of insulin receptor (IR) signaling on hepatic apoA-I metabolism. The experimental approach was to compare hepatic apoA-I expression, secretion and cellular localization in IRfl/fl mice and LIRKO mice in which hepatic insulin receptors were specifically deleted by AAV delivered Cre-recombinase. Results showed that IR mRNA and protein levels were markedly reduced in the livers of LIRKO mice compared to control IRfl/fl mice. As expected, LIRKO mice exhibited decreased glucose tolerance and reduced hepatic insulin signaling. Knockdown of hepatic IR decreased plasma HDL cholesterol and apoA-I levels. Whereas apoA-I mRNA levels were similar in LIRKO and control hepatocytes, apoA-I protein levels were increased in both the liver and primary hepatocytes isolated from LIRKO mice. In contrast to apoA-I, apoE and apoB protein levels in the liver and in cultured hepatocytes, as well as in the plasma, were similar in LIRKO and control mice. ApoA-I accumulation in LIRKO hepatocytes was associated with a decreased rate of apoA-I secretion. Immunofluorescence staining demonstrated that apoA-I accumulated in LIRKO hepatocytes in membrane bound inclusions. These inclusions shared markers characteristic of early, late and recycling endosomes, and of lysosomes. We conclude that IR-mediated insulin signaling plays an important role in hepatic apoA-I secretion and consequent nascent HDL formation. Reduced apoA-I secretion from liver into the circulation may contribute to the lower HDL levels typically associated with insulin resistance.
Abstract 183: Loss of Notch1 Signaling in Endothelial Cells Suppresses Progression of Atherosclerosis
Authors: Liu Zhao-Jun , Li Yan , Zhang Leiming , Regueiro Manuela M , Wei Yuntao , Velazquez Omaida C
Published: July 2021

Introduction:
Notch signaling plays pivotal roles in vascular development and cardiovascular disease. Our previous studies showed that the Notch pathway is activated in luminal endothelial cells (EC) at atherosclerotic plaques and results in pro-inflammatory response and senescence of EC, implicating a potential involvement of Notch signaling in atherosclerosis. Here, we investigate the role of Notch signaling in atherosclerosis using genetic mouse model with inducible endothelial cell-specific Notch1 gene deletion on an ApoE-deficient background.

Methods:
A genetically engineered mouse model,

Notch1
FLOX/FLOX
/VE-cadherin-CreER
T2
/ApoE
-/-
,

which is a Tamoxifen-inducible endothelial cell-specific Notch1 gene knockout mouse on atherosclerosis-prone ApoE-deficient background, was established. Mice were fed with high-fat-diet (HFD) along with or without Tamoxifen treatment (i.p. 2 mg/day for 5 consecutive days) starting from 4-wk old and terminated on 16-wk old. Aortas were harvested to study the effects of loss of Notch1 signaling in endothelial cells on the progression of aortic atherosclerosis. Deletion of Notch1 in endothelial cells was validated by immunostaining. Aortic plaque burden was evaluated by quantification of proportion of total aorta containing atherosclerosis detected by Oil-Red-O and hematoxylin-eosin staining using computer-aided image analysis. Blood was tested to measure lipid profile.

Results:
Notch1 is deleted from endothelial cells in Tamoxifen-treated mice. Loss of endothelial Notch1 signaling significantly decreased aortic plaque burden [n=10 (Tamoxifen -) and 12 (Tamoxifen +),
P
<0.05]. The serum levels of total cholesterol, HDL, LDL, triglycerides and glucose were comparable between Tamoxifen-treated and -untreated mice.

Conclusions:
Inactivation of endothelial Notch1 signaling inhibits atherosclerotic plaque formation. The decrease in atherosclerosis was not due to changes in the serum levels of total cholesterol, HDL, LDL, triglycerides and glucose. Our findings demonstrate that loss of Notch1 signaling in endothelial cells suppresses progression of atherosclerosis. It highlights Notch1 signaling as an emerging therapeutic target for the treatment of atherosclerosis.
Abstract 190: The Role of Hepatic FoxO Transcription Factors in HDL-Mediated Reverse Cholesterol Transport
Authors: Lee Samuel X , Heine Markus , Schlein Christian , Ramakrishnan Rajasekhar , Liu Jing , Haimi Ido , Ginsberg Henry , Heeren Joerg , Rinninger Franz , Haeusler Rebecca
Published: July 2021

Insulin resistance and type 2 diabetes are associated with low levels of high-density lipoprotein-cholesterol (HDL-C). The insulin-repressible FoxO transcription factors are potential mediators of insulin’s effect on HDL-C. FoxOs mediate a substantial portion of insulin-regulated transcription, and poor FoxO repression is thought to contribute to the excessive glucose production in diabetes. In this work, we show that mice with liver-specific triple FoxO knockout (L-FoxO1,3,4), which are known to have reduced hepatic glucose production, also have increased HDL-C. This was associated with decreased expression of HDL-C clearance factors, scavenger receptor class B type I (SR-BI) and hepatic lipase, and defective selective uptake of HDL-cholesteryl ester by the liver. The phenotype could be rescued by re-expression of SR-BI. These findings demonstrate that hepatic FoxOs are required for cholesterol homeostasis and HDL-mediated reverse cholesterol transport to the liver.
Abstract 217: LOX-1 Primarily Contributes to M1 Macrophage Induced Foam Cell Formation
Authors: Popovic Branimir , Millin Antonella , Bakthavatsalam Deenadayalan , Velayutham Murugesan , Post Steven , Nagarajan Shanmugam
Published: July 2021

Objectives:
Modified LDL uptake by macrophages (MΦ) leading to foam cell formation is an early event in atherosclerosis. Recent studies suggest that MΦ polarization contributes to the progression of atherosclerosis. Therefore, we investigated the hypothesis that macrophage plasticity affects modified LDL uptake and subsequent foam cell formation.

Approach & Results:
Bone marrow-derived MΦ were treated with LPS and IFNγ or IL-4 to induce MΦ polarization to M(LPS/IFNγ or M1) and M (IL4 or M2) phenotypes. Foam cell formation was determined after incubating M(LPS/IFNγ) and M(IL4) MΦ with oxidized-LDL. Our results show that formation of foam cells was marginally increased in M(IL4) MΦ compared to un-polarized M(-) MΦ. However, accumulation of neutral lipids was higher in M(LPS/IFNγ) MΦ compared to M(IL4) MΦ indicating that foam cell formation is enhanced by polarization to pro-inflammatory M(LPS/IFNγ) MΦ. Interestingly, mRNA and protein expression of CD36, one of the major scavenger receptors, were lower in M(LPS/IFNγ) MΦ compared to un-polarized MΦ. To assess the specific contribution of CD36, foam cell formation was assessed in MΦ isolated from CD36-deficient mice. Notably, oxidized-LDL uptake and foam cell formation in CD36-deficient M(LPS/IFNγ) MΦ was similar to M(LPS/IFNγ) MΦ from wild type mice. This indicates that CD36 does not mediate the increased foam cell formation in M(LPS/IFNγ) MΦ. We therefore examined expression of LOX-1, another scavenger receptor implicated in foam cell formation. We found that both mRNA and protein expression for LOX-1 increased several fold in M(LPS/IFNγ) MΦ. We also showed that TLR4-mediated NF-κB activation is the primary mechanism for the increased LOX-1 expression and foam cell formation in M(LPS/IFNγ) polarized MΦ.

Conclusion:
Macrophage plasticity, specifically polarization of MΦ to pro-inflammatory M(LPS/IFNγ) phenotype promotes foam cell formation, which has implications for the progression of atherosclerosis.