bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 122: Increased Plasma Sulfide in Vascular Surgery Patients Correlates with Reduced Post-Operative Mortality
Authors: Trocha Kaspar , Longchamp Alban , Hine Chistopher , MacArthur Michael , Ganahl Janine , Kip Peter , Tao Ming , Nagy Peter , Ozaki C. Keith , Mitchell James R.
Published: March 2019

Objective:
Hydrogen sulfide (H
2
S) is an endogenously produced gaseous signaling molecule with the potential to modulate vascular functions. Free plasma sulfide can be measured by various techniques, but no consistent relationship with cardiovascular disease has yet emerged. For example, sulfide levels are decreased in CHF patients, but elevated in PAD. We therefore sought to compare plasma sulfide levels from PAD patients to matched controls, and explore links between mortality rates and sulfide levels using two assays.

Approach & Results:
Patients undergoing carotid endarterectomy (n=49), open lower extremity revascularization (n=44) or leg amputation (n=22) were enrolled (mean age 68.9±9.6, 67% male). Blood was collected from 20 matched control patients, without PAD or CAD (mean age 67.9± 1.3, male 65%). Plasma sulfide was measured using two methods, first detection using lead acetate, and second using mass spectrometry. Controls had increased plasma sulfide levels measured by both methods (lead acetate, Fig. A; mass spec, Fig. B) compared to PAD patients (p<0.001, p=0.013). Also, PAD patients were divided into high (n=57) and low (n=58) sulfide (lead acetate) groups by median split. Low sulfide PAD patients had increased probability of post-op mortality (p=0.0337, Fig. C). To determine the source of plasma H
2
S detected by lead acetate, we tested the effects of detergent and proteolytic denaturation of plasma as well as of reducing agents on H
2
S release. We found denaturation increased plasma sulfide release, and that dithiothreitol was most effective at liberating H
2
S, suggesting bound sulfane sulfur as source of H
2
S detected using the lead acetate assay.

Conclusions:
Plasma free and bound sulfide were reduced in PAD patients compared to controls, and correlated with mortality. These findings provide evidence linking circulating sulfide to clinically meaningful events, and support directed H
2
S investigations toward diagnostic and therapeutic purposes.
Abstract 124: Radiotracer Imaging of Serial Changes in Angiosome Foot Perfusion in Critical Limb Ischemia Patients Undergoing Lower Extremity Revascularization: Association With 12-month Limb Salvage Outcomes
Authors: Chou Ting-Heng , Alvelo Jessica L , Papademetris Xenophon , Sumpio Bauer , Sinusas Albert J , Mena-Hurtado Carlos , Stacy Mitchel R
Published: March 2019

Introduction:
Single photon emission computed tomography (SPECT)/CT imaging is a standard approach for assessing myocardial perfusion, but has not been traditionally applied for evaluating peripheral vascular disease (PVD). Due to the prevalence of extremity perfusion abnormalities in PVD patients, SPECT/CT imaging may allow for sensitive physiological evaluation of regional changes in perfusion within the lower extremities following revascularization. Therefore, we assessed regional changes in angiosome foot perfusion following percutaneous revascularization in diabetic patients with critical limb ischemia (CLI) to evaluate the association between treatment-induced perfusion responses and clinical outcomes.

Methods:
Diabetic patients with CLI and non-healing ulcers (n=24) underwent SPECT/CT perfusion imaging of the feet before and after revascularization (Fig. 1A). CT images were segmented into angiosomes (i.e. vascular territories of the foot), and radiotracer uptake was expressed as standardized uptake values (SUVs). Post-treatment changes in perfusion within ulcerated angiosomes were quantified and limb salvage outcomes were assessed for the following 12 months.

Results:
Post-revascularization changes in perfusion were significantly higher in patients who experienced limb salvage compared to patients who underwent amputation in the 12-months after treatment (Fig. 1B). When patients were divided into groups (high and low perfusion responders) based on median perfusion response, patients with higher percent change in perfusion demonstrated a significantly higher incidence of amputation free survival (p=0.005; Fig. 1C).

Conclusion:
SPECT/CT imaging detects regional changes in foot perfusion following revascularization that are associated with limb salvage outcomes. Application of SPECT/CT perfusion imaging in the evaluation of PVD could assist with characterizing treatment success and predicting clinical outcomes.
Abstract 126: Genome Wide Association Study in the Million Veteran Program Identifies a Novel Role for Thrombosis in the Pathogenesis of Peripheral Artery Disease
Authors: Klarin Derek , Lynch Julie , Aragam Krishna , Assimes Tim , Lee Kyung , Shao Qing , Chaffin Mark , Natarajan Pradeep , Arya Shipra , Small Aeron , Sun Yan V , Saleheen Danish , Lee Jennifer S , Miller Donald , Reaven Peter , DuVall Scott , Boden William , Gaziano J. Michael , Concato John , Kathiresan Sekar , Rader Daniel J , Cho Kelly , Wilson Peter W , Chang Kyong-Mi , O'Donnell Christopher J , Tsao Phil S , Damrauer Scott M ,   VA Million Veteran Program
Published: March 2019

Introduction:
PAD is a leading cause of cardiovascular morbidity and mortality. Previously published GWAS have been limited by small sample sizes and have only identified 3 genome-wide significant (P<5x10
-8
) risk loci to date.

Hypothesis:
DNA sequence variants affecting multiple biological pathways are associated with PAD risk.

Methods:
Using electronic health record data, we identified individuals with and without clinical PAD from the 353,323 Million Veteran Program (MVP) participants genotyped on a customized Affymetrix Biobank array. We tested 32 million genotyped and imputed DNA variants for association with clinical PAD separately in participants of European (EUR), African (AFR), and Hispanic (HIS) ancestry using logistic regression models controlling for age, sex and population structure, and then performed trans-ethnic meta-analysis. The results were replicated with data from the UK Biobank.

Results:
We identified 31,307 individuals (24,009 EUR, 5,373 AFR, 1,925 HIS) with, and 211,753 individuals without, PAD. Following meta-analysis and replication, there were 19 genome-wide significant risk loci associated with PAD. We replicated a known association at
9p21
(P=4.3 x10
-39
), and identified several novel loci associated with PAD that were previously known to be associated with atherosclerosis (
LPA
,
HDAC9
), diabetes (
TCF7L2
), lipid levels (
LPL
,
CELSR2
), and tobacco use (
CHRNA3
). We also identified a novel association with PAD for the Factor V Leiden (FVL) mutation (OR 1.20, P=1.6x10
-12
), which remained significant after controlling for venous thromboembolism (OR 1.10, P=8.7x10
-4
). Sensitivity analysis demonstrated FVL is associated with increasing risk estimates for PAD severity (claudication OR 1.19, P=0.0012; rest pain OR 1.41, P=0.004; tissue loss OR 1.57, P=7x10
-9
).

Conclusions:
Using the MVP, we assembled the largest reported cohort of individuals with clinical PAD and genetic data worldwide. Our data replicate known causal risk factors and identify a novel association for FVL and its putative role for thrombosis in the development of clinical PAD.
Abstract 129: Parthenolide Inhibits Inflammatory Dysfunction of Human Aortic Endothelial Cells and Proliferation of Smooth Muscle Cells in vitro and Restenosis in a Rat Model
Authors: Wang Bowen , Zhang Mengxue , Shi Xudong , Guo Lian-Wang , Kent Craig
Published: March 2019

Background:
Cardiovascular diseases remain the leading cause of death in developed countries. Endovascular surgical interventions trigger uncontrolled proliferation of smooth muscle cells (SMCs) in the intima (intimal hyperplasia) leading to lumen re-narrowing (restenosis). Despite extensive efforts devoted to therapeutic methods with a focus on inhibiting SMC proliferation, restenosis persists at a significant rate. In recent years, a growing body of knowledge has underscored a crucial role for endothelium damage in the pathophysiology of restenosis, suggesting that preservation of the endothelium would provide an effective approach for effectively curbing restenosis.

Methods and Results:
We utilized high-throughput screening methods to search for small molecules that could inhibit the proliferation of human aortic SMCs without damaging human aortic endothelial cells (ECs). We identified such a lead compound in Prestwick Library;
i.e.
Parthenolide, a sesquiterpene lactone extracted from feverfew. Treatment with a low dose (1 μM) of Parthenolide for 96h inhibited SMC but not EC proliferation. When the cells were stimulated with inflammatory cytokines (TNF-α or IL-1β), Parthenolide mitigated cytokine-induced proliferation and MCP-1 production of SMCs, but rescued cytokine-induced endothelial dysfunction, including apoptosis, proliferation, decrease of eNOS, and increase of inflammatory markers. Mechanistic studies showed that while Parthenolide treatment in both SMCs and ECs induced NRF-2 activation (nuclear translocation), NRF-2 knockdown with siRNA diminished the aforementioned beneficial effects of Parthenolide in both cell types. In contrast, NFkB activation was not significantly affected by Parthenolide. In a rat balloon angioplasty model, perivascular delivery of Parthenolide in Pluronic gel effectively inhibited intimal hyperplasia and restenosis 14 days after surgery.

Conclusion:
These results indicate that the natural compound Parthenolide differentially attenuates pathological behaviors of both human vascular SMCs and ECs, whereas known agents as such are scarce. Thus Parthenolide may serve as a promising lead compound for future development of next-generation anti-restenotic therapeutics.
Abstract 131: P2Y
6
Receptor Inhibition Impairs Arteriogenesis
Authors: McEnaney Ryan M , McCreary Dylan , Tzeng Edith
Published: March 2019

Purinergic signaling plays a role in vessel remodeling among developing collateral arteries. We have previously shown that the P2Y
2
receptor, an ATP/UTP receptor, mediates arteriogenesis in a murine model of hindlimb ischemia. Intra-arterial administration of UTP increases perivascular inflammation and macrophage accumulation, necessary early events of arteriogenesis, an effect which was abolished among P2Y
2
-/- mice. Extracellular nucleotides can be dephosphorylated by ectonuclotidases which are expressed in various tissues, converting ATP/UTP into ADP/UDP. Our objective was to identify whether receptors for these derivative nucleotides would also have a role in arteriogenesis. Muscular branches of the caudal femoral artery were explanted from rat and assessed for purinergic receptor expression by immunofluorescence. Baseline expression of P2Y
2
is found among endothelial cells predominantly. Conversely, the P2Y
6
receptor is highly expressed in the media, with no appreciable staining in the endothelium. CD39, an ectonucleotidase, is expressed among VSMCs in developing collateral arteries (Figure). We then sought to identify whether inhibition of the P2Y
6
receptor, the ligand for which is UDP, would alter perfusion recovery after femoral artery ligation (FAL). Selective P2Y
6
receptor antagonist MRS2578 was intraperitoneally delivered via osmotic minipump at a rate of 20 ng/hr. FAL was performed and perfusion recovery monitored over 14 days using laser Doppler perfusion imaging (LDPI). Perfusion recovery was reduced in animals treated with MRS2578 when compared to vehicle (DMSO) at 7 and 14 days (figure). Two (out of 12) animals receiving MRS2578 were euthanized due to gangrene of the hindlimb. We have demonstrated in this work that the P2Y
6
receptor is another mediator of arteriogenesis. Our results also suggest an interesting spatial localization of purinergic receptors among resident vascular cells which may facilitate their function in arteriogenesis.
Abstract 134: The Current Patency Rate of Autologous Arteriovenous Fistula in the Snuff-Box and the Risk Factors for Its Failure
Authors: Okuyama Michihiro , Fujii Yasuhiro , Kobayashi Yasuyuki , Muraoka Genya , Otaka Nozomu , Oozawa Susumu , Uchida Haruhito A , Kasahara Shingo
Published: March 2019

Introduction:
Autologous snuff-box arteriovenous fistula (sAVF) is the first choice procedure as the primary AVF for chronic hemodialysis at this institution. The patency of the autologous AVF in the forearm was reported to be 43% to 85% at 1 year and 40 % to 69 % at 2 years. However, little is known about the patency of sAVF alone to date. In addition, there is a paucity of evidence for risk factors of its failure.

Objectives:
The purpose of this study was to describe the patency of sAVF and to verify the risk factors for its failure.

Methods:
Clinical records were retrospectively reviewed in 185 patients (114 male and 71 female patients) who underwent sAVF creation at our institution between March 2011 and December 2016. The average age was 64 ± 14 years (range, 23 to 90 years). The sAVF was created in the left and right arms in 155 patients and 30 patients, respectively. Nine patients had collagen vascular disease (CVD).

Results:
The primary patency rates were 93.0%, 66.9%, and 59.0% at 1 month, 1 year, and 2 years after surgery, respectively. The secondary patency rates were 98.9%, 89.3%, and 85.4% at 1 month, 1 year, and at 2 years after surgery, respectively. On multivariate analysis, female gender (
P
= 0.002), sAVF creation in the right arm (
P
= 0.013), and steroid use (
P
= 0.019) were the significant risk factors for the decreased primary patency rate. CVD (
P
= 0.001) and steroid use (
P
= 0.005) were the significant risk factors for the decreased secondary patency rate.

Conclusions:
The patency rate of sAVF in our institution was comparable to previously reported patency rates for the forearm AVF. A careful observation for sAVF is needed in patients with female gender, history of smoking, sAVF creation in the right arm, CVD, and steroid use.
Abstract 135: Sterol Efflux Function and HDL Associated APOF Levels Associate with Recovery from Stroke
Authors: Plubell Deanna L , Fenton Alexandra M , Minnier Jessica , Clark Wayne , Zakai Neil A , Quinn Joseph F , Alkayed Nabil J , Pamir Nathalie
Published: March 2019

Background:
Prospective cohort studies and meta-analyses examining the relationship between HDL-cholesterol (C) and stroke risk are discordant and question the value of HDL-C as a marker for stroke risk prediction. Changes in HDL-C protein composition and function after acute ischemic stroke, and their relationship to stroke recovery have not been studied. We investigated changes in HDL cholesterol efflux capacity (CEC) and proteome in response to acute ischemic stroke, and their correlation with long-term functional recovery after stroke.

Methods:
Plasma samples were collected from stroke patients either at 24 (early, N = 35) or 96 hours (late, N = 20) after stroke onset, in addition to age matched healthy controls (N = 35). Samples were analyzed for HDL proteome using mass spectrometry, and CEC using three independent assays for macrophage-, ABCA1- and ABCG1-dependent efflux. Stroke recovery was assessed at 3 months after stroke using the Modified Rankin Scores (MRS) and the NIH Stroke Scale (NIHSS).

Results:
Both macrophage- and ABCG1-mediated CEC were reduced by 50% (
P
<0.0001) and 20% (
P
<0.038) in early and late post stroke samples, respectively, compared to the control group. Patients who had comparable or increased CEC between the two-time points had lower NIHSS and MRS indicating better recovery. Proteomic analysis of HDL indicated a distinct time-dependent remodeling post stroke. Coagulation complement cascade proteins (FGB, FGA, A2M, C3) significantly increased (FDR>0.01) early and returned to control levels later, inflammation proteins (SAA1, SAA2, PON1, C4B) increased early and continued to increase. Interestingly, platelet adhesion proteins (DSG1, JUP, ITGB1, ITGA2, TUBB, DNAH3, PF4) were abundantly present in only later samples. Finally, apolipoprotein F (APOF) levels were 2 fold increased at 96 hour when compared to 24hour time points. APOF positively and significantly correlated with NIHSS (r=0.72, P=0.031)

Conclusion:
1) Patients with acute ischemic stroke who maintain or improve HDL CEC post stroke exhibit better recovery scores, 2) Post stroke HDL proteome remodeling is dynamic with distinct time-dependent protein signatures among which APOF correlates positively and strongly with stroke recovery.
Abstract 138: Revascularization Improves the Hemodynamics, Function, and Myopathy of the Legs of Claudicating Patients
Authors: Pipinos Iraklis , Myers Sara , Fuglestad Matthew , Koutakis Panagiotis , Kim Julian KS , Zhu Zhen , Thompson Jonathan R , Ha Duy , Johanning Jason M , Casale George
Published: March 2019

Introduction:
Patients with claudication due to peripheral artery disease (PAD) have walking and quality of life (QOL) limitations associated with development of ischemic myopathy. Characteristics of PAD-related ischemic myopathy include myofiber degeneration, mitochondrial dysfunction, and oxidative damage. We hypothesize that revascularization operations improve lower extremity hemodynamics, function, and QOL with improvements in key indicators of PAD-related ischemic myopathy.

Methods:
Patients undergoing open or endovascular revascularization were evaluated before and 6 months after intervention. QOL was assessed by Short Form-36 (SF-36) and Walking Impairment Questionnaire (WIQ). Walking performance was measured by six-minute walking distance (6MWD) and Gardner maximal Treadmill test (Peak Walking Time - PWT). Calf muscle biomechanics were measured by plantar flexor peak force (PFPF) and power generation (PFPG). Limb hemodynamics were measured with Ankle-Brachial Index (ABI) and myopathy was assessed
via
gastrocnemius biopsy. Myofibers were evaluated for mitochondrial function
via
respirometry while slide mounted specimens of the gastrocnemius were analyzed for biomarkers of morphology (myofiber cross-sectional area) and myofiber oxidative damage (carbonyl groups) by quantitative fluorescence microscopy.

Results:
We recruited 52 patients who underwent 34 open and 18 endovascular revascularizations. Average score improved in 7 of 8 SF-36 (p<0.03) and 4 of 4 WIQ categories (p<0.001). PWT and 6MWD increased 305±75s (111.9%, p<0.001) and 62±17M (21.3%, p<0.001) respectively. PFPF and PFPG increased 9.8±3.1N (17.1%, p=0.001) and 1.6±0.08W/Kg (26.9%, p<0.001) respectively. ABI increased from 0.46±0.03 to 0.87±0.03 (90.4%, p<0.001). Myofiber cross-sectional area increased 458±216 μm
2
(11.1%, p<0.05). Complex I-mediated mitochondrial respiration (normalized to citrate synthase activity) improved 8.1±2.8 (15.4%, p<0.01). Oxidative damage observed as carbonyl groups was reduced 132±60 grayscale units (8.0%, p<0.05).

Conclusions:
Revascularization operations improved the hemodynamics, QOL and leg function of PAD patients in association with improvement in PAD-related ischemic myopathy.
Abstract 150: Monocyte-Platelet Aggregates Correlate With the Prevalence and Severity of Aortic Aneurysms
Authors: Hadi Tarik , Boytard Ludovic , Barone Krista , Rockman Caron , Adelman Mark , Berger Jeffrey S , Ramkhelawon Bhama
Published: March 2019

Objective:
To determine whether monocyte-platelet aggregates (MPA) correlate with aortic aneurysm (AA) prevalence and severity.
BACKGROUND:
Inflammation and intraluminal thrombus are key hallmarks of complex AA. While monocytes fuel inflammation in AA, the contribution of platelets is unknown. We hypothesized that increased platelet activity yields to MPA that drive AA development and indicate disease severity.

Methods:
Blood was collected from 49 symptomatic patients admitted for aneurysm repair procedures (8 thoracic and 41 abdominal) and 36 matched controls. All subjects were on aspirin monotherapy. Platelet responsiveness to agonists was characterized by light transmission aggregometry. Flow cytometry analysis allowed leukocytes (CD45+)/monocytes (CD14+)-platelet (CD61+) aggregates (LPA/MPA) measurements in the blood and profiled MPA in post-surgical aneurysm tissues.

Results:
Platelet aggregation in response to ADP (57% vs. 35% aggregation, p<0.001) and arachidonic acid (24% vs. 16% aggregation, p=0.03), was increased in patients with AA versus controls. LPA (17.7 vs 6.2% CD61+ leukocytes, p=0.002) and MPA (18.0 vs 7.2% CD61+ Monocytes, p=0.008) were robustly increased in AA vs controls. MPA but not LPA was strongly and positively associated with AA size (p<0.0001). To delve into the role of MPA
in situ
in AA sac, platelets and tissue macrophage activation was characterized. Compared to the non-diseased part of the aorta, diseased section had significantly higher platelet infiltration (7.0% vs 1.2% CD61+ cells, p=0.006) and interaction with CD68+ tissue macrophages (8.3% vs. 0.7%, CD61+ macrophages p=0.03). Notably, macrophages highly expressed the adhesion protein, ICAM-1, in the diseased part (39.6 vs 3.3% in the non-diseased section, p<0.001) which further increased to 69.4% (p=0.01) when macrophages were in contact with platelets.

Conclusions:
Our data highlights MPA as a novel mediator valuable to predict AA prevalence and severity.
Abstract 153: Gut Microbiota-derived Lipolysaccarides Are Enhnaced in the Coronary Thrombi of Patients With Myocardial Infarction
Authors: Nocella Cristina , Carnevale Roberto , Calvieri Camilla , Cangemi Roberto , Cammisotto Vittoria , Mangeri Enrico , Dominici Marcello , Arrivi Alessio , Frati Giacomo , D'Amati Giulia , Tanzilli Gaetano , Violi Francesco
Published: March 2019

Background:
Gut microbiota seems to be implicated in the athero-thrombotic process. Its relationship with coronary thrombosis has never been investigated.

Methods:
Serum levels of bacterial lipopolysaccharides (LPS) against Escherichia Coli (EC) and EC DNA amplification by polymerase chain reaction, plasma sP-selectin, a marker of platelet activation, and zonulin, a marker of gut permeability, were measured in patients with ST-elevation myocardial infarction (STEMI) (n=50) or stable coronary disease (SA) (n=50) and controls (n=50). Serum LPS and sP-selectin were also measured in coronary thrombi and coronary blood of patients with STEMI and stable coronary disease, respectively. Immuno-histochemical analysis was performed in coronary thrombi of 12 STEMI patients. Finally, in vitro study was undertaken to evaluate if LPS stimulate leucocyte-platelet interaction.

Results:
Compared to controls, patients with SA and STEMI had higher systemic levels of LPS (p<0.001), sP-Selectin (p<0.001) and zonulin (p<0.001); these variables were higher in STEMI versus SA (p<0.001). LPS was significantly associated with serum zonulin (β=0.421; p<0.001), and sP-Selectin (Rs=0.501; p<0.001). Analysis of DNA Escherichia coli showed positivity in 10% of patients with coronary heart disease and no positivity in controls. Immuno-histochemical analysis of coronary thrombi showed positivity for leucocyte TLR4 and Cathepsin G (70% and 100% respectively). In vitro study showed that leucocyte incubation with LPS elicited formation of platelet aggregates, which were blunted by an inhibitor of Cathepsin G.

Conclusion:
Bacterial LPS is detected in coronary thrombi of STEMI patients and may be implicated in the thrombotic process via leucocyte-mediated platelet activation.
Abstract 164: Synthetic High-Density Lipoprotein Cholesterol Scavengers for the Treatment of Niemann-Pick C Disease
Authors: Fawaz Maria V , Schultz Mark , Azaria Ruth , Ming Ran , Lieberman Andrew , Schwendeman Anna
Published: March 2019

Background:
Niemann-Pick C disease (NPC) is genetic disorder caused by an accumulation of unesterified cholesterol in late endosomes and lysosomes due to defects in
NPC
genes. The levels of ABCA1 gene expression and concentration of high-density lipoproteins (HDL) are significantly decreased in NPC patients. Infusion of synthetic HDL (sHDL) in patients with atherosclerosis has been previously found safe (up to 100 mg/kg) and effective at reducing cholesterol in atheroma. The objective of this study is to identify sHDL composition capable of rescuing cholesterol storage in NPC.

Materials and Methods:
A panel of sHDL formulations was prepared by lyophilization method using commercially available Apolipoprotein A-I mimetic peptide, 5A, complexed in various ratios with phospholipids such as sphingomyelin (SM), palmitoyl-oleoyl phosphatidylcholine (POPC), or dimyristoyl phosphatidylcholine (DMPC). The efficacy of 5A alone and sHDLs was determined in primary patient NPC and wild type fibroblast cells using fluorescent filipin staining and cholesterol efflux assay. Trafficking of sHDL in NPC fibroblasts was assessed by confocal microscopy using fluorescently-labeled sHDL. Finally,
in vivo
study was executed to examine effects of our best sHDL formulation 5A-SM in NPC1 I1061T homozygotes and littermate controls treated with vehicle or sHDL (100 mg/kg, i.p., 3x/wk) for 4 weeks, starting at 7 wks of age. Neurological correction was accessed by the balance beam tests and body weight changes were tracked.

Results:
Treatment of NPC fibroblasts with sHDL resulted in a dose- and time-dependent rescue of lipid storage (5A-POPC<5A-SM<5A-DMPC). Cellular toxicity was observed only for 5A-DMPC (~30%). HDL trafficking studies revealed that sHDLs got endocytosed into cells and co-localized with LAMP1. Additionally, administration of 100 mg/kg 5A-SM resulted in a significant rescue of body weight (p<0.01) in the NPC mice with no toxicity to animals. However, neuro-correction after sHDL treatment in adult mice was not detected. The absence of neuro-correction observed in adult NPC mice suggest that the alternative delivery routes, treatment durations, or sHDL compositions are still needed.
Abstract 165: Proposed Mechanism of Inhibition of Paraoxonase 1 Activity by Isolevuglandins
Authors: Aggarwal Geetika , Davies Sean S
Published: March 2019

Paraoxonase 1 (PON1) is a High Density Lipoprotein (HDL) associated enzyme which binds to ApoAI and demonstrates lactonase, organophosphatase and arylesterase activity. Association of PON1 with ApoAI, results in a hyperactive state where PON1 activity increases 3-fold. Reduced PON1 activity has been consistently linked to increased atherosclerosis, but the mechanisms underlying this inhibition remain unclear. PON1 activity is found to be reduced in the settings of inflammation where myeloperoxidase (MPO) interacts with both ApoAI and PON1. Association of MPO with HDL generates substantial amounts of isolevuglandins (IsoLGs), lipid peroxidation products that irreversibly modify lysyl residues of proteins. We therefore hypothesized that association of MPO with HDL leads to IsoLG modifications of PON1 that reduce its activity. We found that incubating IsoLG with dextran purified HDL crosslinked PON1 and inhibited its PON1 activity (IC
50
7.5 μM). We then used purified recombinant PON1 to further elucidate the mechanism of inhibition. We considered four models for inhibition of PON1 activity by IsoLG: a) IsoLG directly modifies PON1 to render it inactive; b) IsoLG modifies PON1 near the ApoAI binding site so it cannot associate with ApoAI to become hyperactivated, but PON1 retains its basal activity; c) IsoLG modifies ApoAI near the PON1 binding site, blocking PON1 association and subsequent hyperactivation; d) IsoLG crosslinks PON1 associated with ApoAI to render it inactive. We found that incubation of IsoLG with PON1 inhibited both its basal activity and its hyperactivation when modified PON1 was subsequently incubated with HDL. However incubation of HDL with IsoLG for 1 h, but not 24 h, prior to incubating with PON1 resulted in significant loss of PON1 hyperactivity. The initial reaction of IsoLG with lysines forms pyrrole adducts that can still react to crosslink other proteins, but over time these pyrrole adduct oxidize to form non-reactive lactam adducts. Therefore, modification of ApoAI by IsoLG only appears to result in reduced PON1 activity prior to oxidation of ApoAI adducts to non-reactive lactam adducts, suggesting that crosslinking of ApoAI to PON1 drives loss of PON1 activity. Future studies will examine whether small molecule IsoLG scavengers can block MPO mediated inhibition of PON1 activity.
Abstract 167: Mechanism of Increased Low Density Lipoprotein Cholesterol and Decreased Triglycerides with Sodium-glucose Co-transporter 2 Inhibition
Authors: Basu Debapriya , Huggins Lesley-Ann , Scerbo Diego , Obunike Joseph , Mullick Adam E , Di Prospero Nicholas A , Eckel Robert H , Goldberg Ira J
Published: March 2019

Objective:
Although Sodium glucose cotransporter 2 (SGLT2) inhibition in humans sometimes leads to increased levels of low density lipoprotein (LDL) cholesterol, this therapy is associated with marked reduction in cardiovascular disease. In this study, we aimed to determine how SGLT2 inhibition alters circulating lipoproteins.

Approach and Results:
We used a mouse model in which plasma lipoprotein profiles were humanized by expression of human cholesteryl ester transfer protein and human apolipoprotein B100 to determine how SGLT2 inhibition alters lipoprotein profiles. The mice were fed a high fat diet and then were made partially insulin deficient using streptozotocin. SGLT2 was inhibited using a specific anti-sense oligonucleotide or canagliflozin, a clinically available oral SGLT2 inhibitor. Inhibition of SGLT2 increased circulating levels of LDL cholesterol and reduced plasma triglyceride levels. SGLT2 inhibition was associated with increased lipoprotein lipase activity in the post heparin plasma and decreased postprandial lipemia. The changes in lipoprotein metabolism were more significant in mice treated with SGLT2 ASO compared to canagliflozin.

Conclusions:
Our studies in mice recapitulate many of the changes in circulating lipids found with SGLT2 inhibition therapy in humans and suggest that the increased LDL cholesterol found with this therapy is due to greater lipolysis of triglyceride-rich lipoproteins. This change in lipoprotein physiology is likely, in part, to explain the reduced cardiovascular disease found with SGLT2 inhibition.
Abstract 170: Deep Phenotyping of HDL Particles: Characterization of Seven HDL Species and Their Relationship to Cardiometabolic Phenotypes in a Multi-Ethnic Population (Dallas Heart Study)
Authors: Hoeting Natalie , Ayers Colby R , Rohatgi Anand
Published: March 2019

Background:
Size-based HDL particle analysis based on small, medium, and large categories has led to inconsistent associations with cardiovascular disease (CVD). A new algorithm expands characterization of HDL-P from three to seven species, but the clinical significance remains unknown. We investigated the relationships between the seven HDL species and traditional risk factors, lipids, and cardiometabolic phenotypes in the Dallas Heart Study, a multiethnic, probability-based, population cohort of Dallas county adults.

Methods:
This study included 2,996 DHS participants (56% women, 50% Black), excluding those with prior CVD and statin users. HDL species were determined by nuclear magnetic resonance using the LP4 algorithm, with increasing size from H1P to H7P. Insulin resistance was determined by homeostatic model assessment index (HOMA-IR). Visceral fat was measured by MRI.

Results:
The largest HDL species were most directly associated with HDL cholesterol (HDL-C) (H6P: r = 0.61, p < 0.0001; H7P: r = 0.66, p < 0.0001). H2P was inversely associated with all HDL species including H1P (r = -0.19, p < 0.0001) and HDL-C (r = -0.18, p < 0.0001), but was directly associated with total cholesterol, triglycerides, and LDL-C (p < 0.0001). Female gender and Black ethnicity were associated with lower H2P levels (p < 0.0001). H2P alone was directly associated with diabetes, hypertension, waist circumference, insulin resistance, and visceral fat (Figure, p < 0.0001 for all values)

Conclusion:
Our study of a novel 7-species designation of HDL particles revealed that the smallest HDL particle species (H1P and H2P) confer differential associations with cardiometabolic phenotypes. These findings suggest further investigation specifically into the role of H2P and CVD.
Abstract 174: Lipid Levels after Acute Coronary Syndromes: a Perspective from a General Hospital
Authors: Pimentel Filho Pedro , Leivas Justo , Galvão André , Junqueira de Brum Joana Carolina , Michelotti Charline , Roessler Mohr Kauan
Published: March 2019

Background:
Low-density lipoprotein cholesterol (LDL-C) is a risk factor and even cause of atherosclerosis. High dose statins early in all Acute Coronary Syndrome (ACS) patients are now recommended. . Mean serum LDL-C vary relatively little over the early days of ACS and lipid therapy generally is not considered a priority during ACS . Initiation of statin is strongly associated with their use after discharge

Purpose:
To evaluate our data on lipids after ACS and compare with current standards of therapy.

Methods:
100 patients were analyzed during 6 months in 2016 in a step-down unit with ACS -unstable angina (UA), myocardial infarction with ST elevation (STEMI) and without ST elevation (NonSTEMI). Data regarded age, gender, type of ACS, coronary angiogram , medical therapy, lipid levels. Symmetric variables are described by mean and standard deviation(sd) and asymetric by the median and interquartile range. Categorical variables are described by frequencies and percentages . 95% confidence intervals for percentages are presented for main results.

Results:
56 men, 44 women, mean ages 64 years old (sd 12.5); 36 with diabetes; 42 UA, 35 NonSTEMI and 23 STEMI. Coronary angiograms in 98 patients, 4 without lesions . Medical therapy with aspirin in 100, clopidogrel 92,beta blockers 96, ACE inhibitors 63, angiotensin receptor blockers 12, calcium channel blockers 7, diuretics 20 , nitrates 9. Previous statin use in 32 and statin use during hospital stay and discharge in 99. The range of TC was 90 to 291 mg/dL (mean: 167,1; sd 40.8), LDL-C: 39 to 194mg/dL (mean 98.0; sd: 34.1); HDL-C from 20 to 68 mg/dL (mean :34.8; sd: 99.2); Triglycerides from 55 to 615 mg/dl ( median 151.5; interquartile range : 114.5 to 197.0) . Patients with LDL-C ≤ 70 mg/dL : 25% ( CI 95% : 16.9- 34.7); HDL-C ≥40 : 24% (CI 95% : 16.0 - 33.6). Lipid levels were measured in only 12 patients at arrival (CI 95% : 6.4 - 20.0), in 70 during hospital stay (CI 95% : 60.0 - 78.8); in 30 patients no measure at all (CI95% : 21.2 - 40.0).

Conclusion:
Knowledge of serum lipid levels early after ACS is very relevant and should facilitate initiation of lipid lowering therapy. There is still a large gap between current recommendations and clinical practice concerning lipids in ACS, as shown with our data.
Abstract 178: Bioactive Compounds in Fenugreek Ameliorate ER Stress and VLDL Overproduction via the Mediation of Insig Signaling
Authors: Khound Rituraj , Santra Dipak , Su Qiaozhu
Published: March 2019

A number of health-enhancing bioactive compounds have been identified in the seed of fenugreek, an annual legume. These compounds have been shown to exert multiple health beneficial effects on anti-obesity and type 2 diabetes. In this study, we characterized the molecular mechanisms of fenugreek seed in regulating lipid and lipoprotein metabolism and metabolic inflammatory stress. Two groups of hyperlipidemic mice induced by depletion of cAMP responsive element binding protein H were fed either a chow containing 2% fenugreek seed or vehicle control for 7 weeks. Q-RT-PCR and immunoblotting analysis demonstrated that fenugreek seed containing diet inhibited hepatic SREBP-1c activation and the subsequent de novo lipogenesis by enhancing expression of insulin-inducible gene-1 (Insig-1) and gene-2 (Insig-2). mRNA expression of PPARα and its target genes that were involved in fatty acid β-oxidation were also upregulated in the fenugreek seed treated-mice which was accompanied by significantly reduced hepatic lipid accumulation and VLDL secretion and improved endoplasmic reticulum (ER) stress. These actions ameliorated hepatic steatosis and systemic hyperlipidemia. Fenugreek seed further improved insulin sensitivity by upregulating expression of glucose transporters Glut-2 and Glut-4 and enhancing the activity of hepatic inulin signaling molecules, insulin receptor and AKT. In vitro, treating a rat hepatoma cell line, McA-RH7777, with trigonelline, a phytochemical compound in fenugreek seed, increased expression of Insig-2 which prevented the activation of SREBP-1c and the subsequent de novo lipid synthesis, resulting in less secretion of VLDL. Trigonelline treatment also attenuated ER stress induced by a free fatty acid, palmitic acid, indicated by the downregulation of GRP94/78 and reduced phosphorylation of JNK and eIF2α. This study unveiled a novel mechanism of the bioactive compound trigonelline in ameliorating metabolic inflammatory stress, hepatic steatosis, VLDL overproduction and insulin resistance via the mediation of Insig signaling. This evidence lands support for developing fenugreek seed as a nutraceutical supplement for the prevention and treatment of nutrient-surplus associated metabolic disorders.
Abstract 179: CETP Facilitates SAA Exchange Between Lipoproteins
Authors: Wilson Patricia G , Thompson Joel C , Webb Nancy R , de Beer Frederick C , Tannock Lisa R
Published: March 2019

Serum amyloid A (SAA) is a family of acute phase reactants that are elevated in chronic inflammatory conditions such as obesity and diabetes. SAA promotes atherosclerosis in mice. Although SAA is generally thought to be exclusively an HDL apolipoprotein, we and others have detected SAA on apoB-containing lipoproteins in obese/diabetic mice and humans. The goal of this study was to investigate mechanisms underlying SAA exchange between lipoprotein fractions. Obese humans with or without metabolic syndrome or type 2 diabetes were recruited. Plasma samples were collected fasting and hourly for 8h after consumption of a high fat drink. Whereas SAA was found predominantly on HDL in fasting samples, in diabetic subjects SAA shifted from HDL to VLDL and LDL in post prandial samples. Postprandial LDL and VLDL containing SAA had increased proteoglycan binding compared to fasting LDL and VLDL from the same subject. We previously reported that HDLs remodeled by CETP release lipid-free SAA. To determine if CETP facilitates SAA exchange between particles, HDL-containing SAA was incubated with SAA-free VLDL in the presence of increasing amounts of CETP. Even in the absence of CETP, 16±3% of HDL-associated SAA shifted to VLDL; in samples with CETP, 19-28% of total SAA was found on VLDL and up to 17% was lipid-poor/lipid-free. To investigate whether CETP promotes SAA exchange in vivo, SAA-deficient mice that lack CETP were injected with HDL containing SAA and then bled at 1, 3, 6 and 24 hours. Essentially all SAA was found on HDL at each time point. In contrast, in SAA-deficient mice expressing CETP by adenoviral vector, approximately 50% and 20% of SAA was associated with the VLDL and LDL fractions, respectively, 1h after injection of HDL-containing SAA. Thus, increased CETP activity in diabetes may promote the transfer of SAA from HDL to apoB-containing lipoproteins, leading to increased retention in the vasculature.
Abstract 184: Hyperglycemia Enhances Pro-inflammatory Properties of Macrophage-derived Exosomes to Drive Hematopoiesis in Apolipoprotein E-deficient Mouse
Authors: Bouchareychas Laura , Chung Allen , Wong David K , Duong Phat , Raffai Robert L
Published: March 2019

Background and Purpose:
Diabetes is recognized to enhance the frequency and severity of atherosclerosis and cardiovascular disease. Recent studies have shown that hyperglycemia is associated with enhanced hematopoiesis and macrophage accumulation in atherosclerotic lesions. We explored whether high glucose concentrations can enhance intercellular communication between mature macrophages and hematopoietic progenitors via exosomes to promote inflammation and diabetic atherosclerosis.

Methods:
Bone marrow derived macrophages (BMDM) from C57BL/6 mice were cultured with normal (5mM) or high glucose concentrations (25mM). Exosomes were isolated with our cushioned-density gradient ultracentrifugation method followed by nanoparticle tracking and western blot analysis. Pro-inflammatory properties of high glucose exosomes (HGexo) were tested
in vitro
by exposing them to BMDM cultured in normal low glucose. The capacity for BMDM-derived exosomes to alter systemic and vascular inflammation were next tested by infusing 25-30 weeks-old ApoE
-/-
mice fed a chow diet with 3 x 10
10
exosomes three times a week, for four weeks.

Results:
Our data show that HGexo can stimulate the expression of inflammatory cytokines (IL-6, IL-1ß) as well as NADPH oxidases (Nox-1 and Nox-4) in cultured BMDM. Furthermore, our findings show that intraperitoneally injected exosomes distribute to numerous organs and tissues including the bone marrow and the spleen. Lastly, HGexo enhance the expansion of multipotent and lineage committed hematopoietic progenitors.

Conclusions:
We identify that exosomes derived from cultured BMDM exposed to high glucose have the capacity to exert intercellular communication
in vitro
, and
in vivo.
Our findings suggest that exosomes produced by macrophages exposed to hyperglycemia could represent an unsuspected source of inflammation to accelerate atherosclerosis in diabetes.
Abstract 188: Macrophage-associated Lipin-1 Enzymatic Activity Primes Macrophages to Be Hyper-responsive to Additional Proinflammatory Stimulus
Authors: Vozenilek Aimee E , Blackburn Cassidy M , Klein Ronald L , Orr A W , Woolard Matthew D
Published: March 2019

Macrophage proinflammatory responses induced by oxidized low-density lipoproteins (oxLDL) contribute to atherosclerotic progression. Our previous data using mice lacking lipin-1 enzymatic activity in myeloid-derived cells demonstrated that stimulation of bone marrow-derived macrophages with oxLDL activates a lipin-1 dependent persistent PKCα/βII-ERK1/2-cJun signaling cascade that primes the macrophage to be hyper-responsive to subsequent proinflammatory stimulus. To further investigate the impact of lipin-1 enzymatic activity on oxLDL-induced macrophage proinflammatory responses, bone marrow-derived macrophages (BMDMs) were collected from mice lacking lipin-1 enzymatic activity in myeloid-derived cells and littermate control mice. Both the control BMDMs and BMDMs lacking lipin-1 enzymatic activity were then stimulated with oxLDL, lipopolysaccharide (LPS), or oxLDL and LPS. RNA was collected from the BMDMs and RNA sequencing was performed. The goal was to identify transcripts that are altered between the control BMDMs and BMDMs lacking lipin-1 enzymatic activity to define transcription factors and signaling pathways regulated by lipin-1 enzymatic activity on a global level. Our data demonstrates that the loss of lipin-1 enzymatic activity in BMDMs results in a reduction of proinflammatory transcripts, via loss of cJun activity, in response to the combination treatment of oxLDL and LPS when compared to the control BMDMs.
Abstract 197: Active (1,25 OH), but not Inactive (25-OH) Vitamin D levels are inversely associated with aortic Vascular Inflammation, Non-calcified Coronary Plaque Burden and Visceral Adiposity in Psoriasis
Authors: Playford Martin , Dey Amit , Zierold Claudia , Blocki Frank , Bonelli Fabrizio , Joshi Aditya , Teague Heather , Baumer Yvonne , Mehta Nehal N
Published: March 2019

Introduction:
Psoriasis (PSO), a chronic inflammatory disease associated with increased Cardiovascular (CV) risk provides an ideal model to study the role of vitamin D, a known anti-inflammatory molecule in PSO associated CV disease. Vitamin D exists as inactive 25-hydroxyvitamin D (25(OH)D) in the bloodstream which is converted to active 1,25-dihydroxyvitaminD (1,25(OH)2D) in target tissues. Cohort studies reporting CV disease among individuals with low vitamin D are inconsistent and solely measure 25(OH)D. While serum 25(OH)D is routinely measured , we propose that measurement of 1,25(OH)2D may perform better than 25(OH)D as a surrogate for CV disease.

Methods:
Consecutive PSO patients (N=122) and healthy controls (N=35) underwent FDG PET/CT and CCTA scans to measure vascular inflammation/ abdominal adiposity volume and coronary plaque burden respectively. Blood levels of both 1,25(OH)2D and 25(OH)D were measured by chemiluminescence (LIASON XL DIaSorin, Stillwater, MN).

Results:
PSO patients were middle-aged, mostly male, had moderate PSO severity and were at low CV risk by 10-year Framingham risk. PSO patients had lower serum 1,25(OH)2D compared to healthy controls (mean±SEM: 52.4±1.4 pg/ml versus 57.5±2.0, p<0.037) but 25(OH)D was not significantly different (28.7±1.3 versus 27.3±2.2, p=0.30). 1,25(OH)2D, but not 25(OH)D was negatively associated with PASI score beyond adjustment for CV risk factors and systemic/ biological therapy (B=-0.20, p=0.043 vs. B=0.12, p=0.25). Furthermore, serum 1,25(OH)2D but not 25(OH)D was inversely associated with non-calcified coronary burden (B=-0.16, p<0.001 versus B=0.01, p=0.84), vascular inflammation (B=-0.24, p=0.007 versus B=-0.13, p=0.16) and visceral adiposity (B=-0.43, p=0.026 versus B=-0.26, p=0.13) independent of traditional risk factors and statin/PSO therapy.

Conclusion:
Our data support that active 1,25(OH)2D may more accurately capture cardiometabolic disturbance compared to inactive 25(OH)D in humans.
Abstract 198: The Role of PI(4,5)P
2
in LDL Receptor Lysosomal Decay
Authors: Qin Yuanyuan , Kim Mee J , Ting Flora , Strelnikov Jacob , Harmon Joseph , Dose Andrea , Sun Hua , Teng Ba-Bie , Krauss Ronald , Medina Marisa
Published: March 2019

Upregulation of low density lipoprotein receptor (LDLR) activity reduces LDL levels and coronary disease risk. LDLR releases LDL in endosomes after internalization and then is either recycled to the cell surface or transported to lysosomes for decay. The transmembrane protein 55B (TMEM55B) is a phosphatase that hydrolyzes phosphatidylinositol-(4,5)-bisphosphate (PI(4,5)P
2
) and has been found to affect lysosome function. We reported
TMEM55B
regulates cellular cholesterol metabolism by modulating LDLR protein decay.

To evaluate whether
Tmem55b
affects cholesterol metabolism
in vivo
, we treated western diet fed C57BL/6J mice with antisense oligonucleotides against either
Tmem55b
or a non-targeting control for 4 weeks. Hepatic
Tmem55b
transcript and protein levels were reduced by ~70%, resulting in increased plasma total (1.5-fold, p<0.0001) and non-HDL-cholesterol (1.8-fold, p<0.0001). FPLC and ion mobility analyses revealed increased levels of small LDL particles that were enriched in apoE as determined by immunoblot. Notably,
Tmem55b
knockdown had no effect on plasma cholesterol levels in

Ldlr
-/-

mice. Increased LDLc (1.3-fold, p<0.05) was also observed in a murine model that lacks Ocrl, another phosphatase which hydrolyzes PI(4,5)P
2
.

Given the role of the lysosome in LDLR decay, we tested whether
TMEM55B
regulates LDLR via lysosomes. Using confocal microscopy,
TMEM55B
knockdown in HepG2 cells significantly increased PI(4,5)P
2
, decreased LDLR, increased lysosome staining, and reduced LDLR-lysosome colocalization. Impairment of lysosome function by incubation with NH
4
Cl or knockdown of the lysosomal proteins
LAMP1
or
RAB7
abolished the effect of
TMEM55B
knockdown on LDLR. Although there was no change in RAB11 levels, a marker of recycling endosomes, LDLR-RAB11 colocalization was reduced by 50% upon
TMEM55B
knockdown. Finally, incubation of HepG2 cells with PI(4,5)P
2
increased LDL uptake and reversed the inhibitory effect of
TMEM55B
overexpression .

Together, these findings suggest that TMEM55B increases plasma cholesterol through stimulating LDLR lysosomal degradation, reducing LDLR recycling to the plasma membrane through PI(4,5)P
2
, and thereby inhibiting plasma clearance of apoE-containing LDL particles.