bluuebunny/crossref_metadata_2025 huggingface dataset:
Microscopic morphometry of abdominal aorta from men in New Orleans and Guatemala.
Authors: Restrepo C , Malcom G T , Strong J P , Toca V T , Tracy R E
Published: June 2011

Morphometric light microscope measurements were made on 154 abdominal aortas from 77 Guatemalan Indian-white (ladinos) men and from 77 new Orleans white men, aged 15 to 54 years. In each case, means were derived from 12 points measured independently. A progressive increase in intimal lipid with increasing age was observed in men from both countries. Extracellular intimal lipid was consistently higher in men from New Orleans than in those from Guatemala, although not always significantly so. Intimal thickness followed a similar pattern to intimal lipid regarding age and geographic location. Foam cells and leukocytes (mainly monocytes) did not follow a consistent pattern. The smooth muscle cell count was the only variable that was significantly greater in New Orleans men than in Guatemalans aged 15 to 34 years. Morphometric microscopic measurements were significantly correlated with unaided visual estimates of atherosclerotic lesions and with chemical determinations of lipid fractions in the arterial intima. All three methods, gross grading, microscopy, and chemistry, agree in revealing little or nor measureable difference between new Orleans men and Guatemalans younger than 35 years, but an accelerated divergence of the populations over age 35.
Systemic arterial compliance in patients with arteriosclerosis obliterans of the lower limbs. Observations on the effect of intravenous propranolol.
Authors: Levenson J A , Simon A C , Fiessinger J N , Safar M E , London G M , Housset E M
Published: June 2011

Hemodynamic parameters and systemic arterial compliance were measured in patients with arteriosclerosis obliterans of the lower limbs before and after acute administration of propranolol. Arterial compliance was evaluated from a simple viscoelastic model, enabling the calculation of diastolic drainage and diastolic blood flow as indices of the reservoir role of the larger arteries in overall circulation. In comparing basal conditions with normal subjects of the same age, patients with arteriosclerosis obliterans exhibited a significant decrease in arterial compliance (p less than 0.01) and heart rate (p less than 0.02) with a significant increase in systolic pressure (p less than 0.001). Diastolic drainage was increased (p less than 0.01) and was positively correlated with diastolic time (r = 0.73, p less than 0.001). Diastolic blood flow remained within normal ranges (52 +/- 2 vs 49 +/- 3 ml/m2/sec). After acute propranolol intravenous administration, heart rate and stroke volume decreased (p less than 0.001), while total peripheral resistance increased (p less than 0.001). Systemic arterial compliance and diastolic blood flow significantly decreased (p less than 0.01). The study provided evidence that in patients with arteriosclerosis obliterans, the diastolic blood flow was maintained in basal conditions despite the observed reduction in arterial compliance, and that intravenous propranolol administration decreased systemic arterial compliance and diastolic blood flow.
Use of 3H-cholesteryl linoleyl ether for the quantitation of plasma cholesteryl ester influx into the aortic wall in hypercholesterolemic rabbits.
Authors: Stein Y , Stein O , Halperin G
Published: June 2011

In this study use was made of 3H-cholesteryl linoleyl ether CLE), a nondegradable analogue of cholesteryl ester (CE) to measure plasma lipoprotein CE influx into rabbit aorta. Autologous serum labeled with 3H-CLE was injected into seven hypercholesterolemic rabbits, and more than 90% of the label was recovered in the plasma compartment 10 minutes after injection. Between 4 hours and 3 days the label was cleared from the circulation with a t1/2 of about 24 hours. Between 4 and 24 hours the lipoproteins isolated at d less than 1.006, d less than 1.019, and d less than 1.063 approached similar specific activity, assuming that 3H-CLE had mixed with the lipoprotein CE pool. The rabbits were killed 7 to 14 days after injection when plasma radioactivity decreased to less than 0.03% of injected dose/ml. Total recovery of the CLE ranged from 70% to 95% and 48% to 72% were found in the liver. The minimum influx of plasma CE into the aortic intima was determined by dividing the label found in the artery by the mean specific activity of the labeled compound in the plasma. The minimum influx into regions with atheromatous involvement ranged from 0.8 to 3.4 micrograms CE/cm2/hr. The rate of influx was highly correlated with the amount of CE mass in the intima and media indicating that the bulk of aortic CE is derived from plasma lipoprotein CE. The method described might be useful in distinguishing between possible effects of "antiatherogenic" drugs on plasma CE influx into the aortic wall from an effect on intracellular CE hydrolysis and subsequent efflux of free cholesterol from the artery.
The Heparin-Binding Proteins Apolipoprotein E and Lipoprotein Lipase Enhance Cellular Proteoglycan Production
Authors: Obunike Joseph C. , Pillarisetti Sivaram , Paka Latha , Kako Yuko , Butteri Mathew J. , Ho Yuan-Yaun , Wagner William D. , Yamada Nobuhiro , Mazzone Theodore , Deckelbaum Richard J. , Goldberg Ira J.
Published: June 2011

Abstract
—Apolipoprotein E (apoE) and lipoprotein lipase (LPL), key proteins in the regulation of lipoprotein metabolism, bind with high affinity to heparin and cell-surface heparan sulfate proteoglycan (HSPG). In the present study, we tested whether the expression of apoE or LPL would modulate proteoglycan (PG) metabolism in cells. Two apoE-expressing cells, macrophages and fibroblasts, and LPL-expressing Chinese hamster ovary (CHO) cells were used to study the effect of apoE and LPL on PG production. Cellular PGs were metabolically labeled with
35
[S]sulfate for 20 hours, and medium, pericellular PGs, and intracellular PGs were assessed. In all transfected cells, PG levels in the 3 pools increased 1.6- to 3-fold when compared with control cells. Initial PG production was assessed from the time of addition of radiolabeled sulfate; at 1 hour, there was no difference in PG synthesis by apoE-expressing cells when compared with control cells. After 1 hour, apoE-expressing cells had significantly greater production of PGs. Total production assessed with [
3
H]glucosamine was also increased. This was due to an increase in the length of the glycosaminoglycan chains. To assess whether the increase in PGs was due to a decrease in PG degradation, a pulse-chase experiment was performed. Loss of sulfate-labeled pericellular PGs was similar in apoE and control cells, but more labeled PGs appeared in the medium of the apoE-expressing cells. Addition of exogenous apoE and anti-human apoE antibody to both non–apoE-expressing and apoE-expressing cells did not alter PG production. Moreover, LPL addition did not alter cell-surface PG metabolism. These results show that enhanced gene expression of apoE and LPL increases cellular PG production. We postulate that such changes in vascular PGs can affect the atherogenic potential of arteries.
Fish Oil Supplementation Prevents Neointima Formation in Nonhypercholesterolemic Balloon-Injured Rabbit Carotid Artery by Reducing Medial and Adventitial Cell Activation
Authors: Faggin Elisabetta , Puato Massimo , Chiavegato Angela , Franch Rafaella , Pauletto Paolo , Sartore Saverio
Published: June 2011

Abstract
—We asked whether balloon-injured neointima formation in the presence of high/low serum cholesterol (CT) levels might be affected by dietary supplementation with fish oil (FO). To test this hypothesis, we examined the differentiation, proliferation, or apoptosis profile of smooth muscle cell (SMC) and adventitial cell response to a mild injury induced via a Fogarty catheter in the carotid artery of adult rabbits that had been fed a standard chow or 0.5% CT-enriched diet starting 4 weeks before the lesion. One week before surgery, animals received FO supplementation. This regimen was continued for the following 3 weeks. The effect of FO on the early proliferative/migratory response of carotid SMCs was also examined in 2- and 7-day–injured normocholesterolemic rabbits. As controls, animals subjected to 3-week endothelial injury and animals kept on a 7-week CT diet were used. Carotid cryosections from the various animal groups were evaluated for morphometry (image analysis), differentiation (immunofluorescence with monoclonal antibodies specific for smooth muscle markers, ie, myosin isoforms, SM22, and fibronectin), proliferation (bromodeoxyuridine incorporation), and apoptosis (terminal deoxynucleotidyl transferase–mediated dUTP nick end-labeling). FO treatment significantly reduced the development of intimal thickening in normocholesterolemic rabbits but had no efficacy in the presence of relatively higher serum CT levels. At day 2 (adventitia) and day 7 (neointima, media, and adventitia), the proliferation index of SMCs in FO-treated injured rabbits was markedly lower than in untreated injured controls. Concomitantly with the antiproliferative effect, FO was able to decrease the size of 2 cell types involved in the cell growth response to endothelial injury, namely, the “fetal-type” medial SMC subpopulation and the fibroblast-derived adventitial myofibroblasts. Thus, in our experimental conditions, a low CT level is a permissive condition for FO to prevent neointima formation to a considerable extent. This event is attributable to the early postinjury effect of FO on SMC/adventitial cell proliferation/differentiation patterns.
Modulation of Protein Kinase Activity and Gene Expression by Reactive Oxygen Species and Their Role in Vascular Physiology and Pathophysiology
Authors: Griendling Kathy K. , Sorescu Dan , Lassègue Bernard , Ushio-Fukai Masuko
Published: June 2011

Abstract—Emerging evidence indicates that reactive oxygen species, especially superoxide and hydrogen peroxide, are important signaling molecules in cardiovascular cells. Their production is regulated by hormone-sensitive enzymes such as the vascular NAD(P)H oxidases, and their metabolism is coordinated by antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. Both of these reactive oxygen species serve as second messengers to activate multiple intracellular proteins and enzymes, including the epidermal growth factor receptor, c-Src, p38 mitogen-activated protein kinase, Ras, and Akt/protein kinase B. Activation of these signaling cascades and redox-sensitive transcription factors leads to induction of many genes with important functional roles in the physiology and pathophysiology of vascular cells. Thus, reactive oxygen species participate in vascular smooth muscle cell growth and migration; modulation of endothelial function, including endothelium-dependent relaxation and expression of a proinflammatory phenotype; and modification of the extracellular matrix. All of these events play important roles in vascular diseases such as hypertension and atherosclerosis, suggesting that the sources of reactive oxygen species and the signaling pathways that they modify may represent important therapeutic targets.
Metabolic Cardiovascular Syndrome and Risk of Dementia in Japanese-American Elderly Men
Authors: Kalmijn S. , Foley D. , White L. , Burchfiel C. M. , Curb J. D. , Petrovitch H. , Ross G. W. , Havlik R. J. , Launer L. J.
Published: June 2011

Abstract
—Cardiovascular risk factors often cluster into a metabolic syndrome that may increase the risk of dementia. The objective of the present study was to assess the long-term association between clustered metabolic cardiovascular risk factors measured at middle age and the risk of dementia in old age. This prospective cohort study of cardiovascular disease was started in 1965 and was extended to a study of dementia in 1991. The subjects were Japanese-American men with an average age of 52.7±4.7 (mean±SD) years at baseline. Dementia was diagnosed in 215 men, according to international criteria, and was based on a clinical examination, neuropsychological testing, and an informant interview. The
z
scores were calculated for 7 risk factors (random postload glucose, diastolic and systolic blood pressures, body mass index, subscapular skinfold thickness, random triglycerides, and total cholesterol). The relative risk (RR [95% CI]) of dementia (subtypes) per 1 SD increase in the sum of the
z
scores was assessed after adjustment for age, education, occupation, alcohol consumption, cigarette smoking, and years of childhood lived in Japan. The
z
-score sum was higher in demented subjects than in nondemented subjects, indicating a higher risk factor burden (0.74 versus −0.06, respectively;
P
=0.008). Per SD increase in the
z
-score sum, the risk of dementia was increased by 5% (RR 1.05, 95% CI 1.02 to 1.09). The
z
-score sum was specifically associated with vascular dementia (RR 1.11, 95% CI 1.05 to 1.18) but not with Alzheimer’s disease (RR 1.00, 95% CI 0.94 to 1.05). Clustering of metabolic cardiovascular risk factors increases the risk of dementia (mainly, dementia of vascular origin).
Replication of Linkage of Familial Combined Hyperlipidemia to Chromosome 1q With Additional Heterogeneous Effect of Apolipoprotein A-I/C-III/A-IV Locus
Authors: Coon Hilary , Myers Richard H. , Borecki Ingrid B. , Arnett Donna K. , Hunt Steven C. , Province Michael A. , Djousse Luc , Leppert Mark F.
Published: June 2011

Abstract—Familial combined hyperlipidemia (FCHL), the most common familial dyslipidemia, is implicated in up to 20% of cases of premature coronary heart disease. Although underlying mutations for FCHL have yet to be identified, several candidate genes/regions have been identified. A positive linkage to chromosome 1q markers has been reported, with the highest lod score of 5.93 occurring at a location between D1S104 and D1S1677. Using the same diagnostic criteria, the Family Heart Study (FHS) has defined 71 FCHL families, comprising 170 cases, for a total of 137 possible affected sibling pairs. The FCHL criteria require elevation in serum low density lipoprotein cholesterol and triglyceride levels within the family, with at least 2 affected first-degree relatives. Markers D1S104 and D1S1677 were typed, and significant allele sharing was found in FCHL sibships (multipoint lod score with use of the model from the Finnish study was 2.52, and multipoint nonparametric score was 2.48;P=0.007), replicating linkage in this chromosome 1 region. In addition, previously reported linkage of FCHL to apolipoprotein A-I/C-III/A-IV has been investigated in FHS families. FHS results revealed positive but nonsignificant allele sharing among FCHL sibships with apolipoprotein A-I/C-III/A-IV by use of marker D11S4127 (nonparametric linkage score 1.11,P=0.13). Two-locus analyses of D1S104 and D11S4127 suggested possible heterogeneity rather than epistasis, with a maximum 2-locus lod score of 3.05. A nonparametric 2-locus analysis revealed significant improvement in the 2-locus versus single-locus scores. Finally, no linkage was found with markers near the lipoprotein lipase gene region.
Polymorphisms of the Human Matrix Gla Protein (
MGP
) Gene, Vascular Calcification, and Myocardial Infarction
Authors: Herrmann Stefan-Martin , Whatling Carl , Brand Eva , Nicaud Viviane , Gariepy Jérôme , Simon Alain , Evans Alun , Ruidavets Jean-Bernard , Arveiler Dominique , Luc Gerald , Tiret Laurence , Henney Adriano , Cambien François
Published: June 2011

Abstract
—The matrix Gla protein (MGP) is an important inhibitor of vessel and cartilage calcification that is strongly expressed in human calcified, atherosclerotic plaques and could modulate plaque calcification and coronary heart disease risk. Using a genetic approach, we explored this possibility by identifying polymorphisms of the
MGP
gene and testing their possible association with myocardial infarction (MI) and plaque calcification. Eight polymorphisms were identified in the coding and 5′-flanking sequences of the
MGP
gene. All polymorphisms were investigated in 607 patients with MI and 667 control subjects recruited into the ECTIM Study (Etude Cas-Témoins de l’Infarctus du Myocarde) and in 717 healthy individuals with echographically assessed arterial calcification and atherosclerosis who were participating in the AXA Study. In the ECTIM Study, alleles and genotypes were distributed similarly in patients and controls in the whole study group; in only 1 subgroup of subjects defined as being at low risk for MI were the concordant
A
−7 and Ala 83 alleles more frequent in patients with MI than in controls (
P
<0.003). In the AXA Study among subjects with femoral atherosclerosis, the same alleles were more common in the presence than the absence of plaque calcification (
P
<0.025). The other
MGP
polymorphisms were not associated with any investigated clinical phenotype. Transient transfection experiments with allelic promoter-reporter gene constructs and DNA-protein interaction assays were carried out to assess possible in vitro functionality of the promoter variants detected at positions −814, −138, and −7 relative to the start of transcription. When compared with the −138
T
allele, the minor −138
C
allele consistently conferred a reduced promoter activity of −20% (
P
<0.0001) in rat vascular smooth muscle cells and of −50% (
P
<0.004) in a human fibroblast cell line, whereas the other polymorphisms, including −7, displayed no evidence of in vitro functionality. We conclude that the
A
−7 or Ala 83 alleles of the
MGP
gene may confer an increased risk of plaque calcification and MI; however, the observed relationships are weak or limited to subgroups of patients and therefore need confirmation.
Factor Xa Activates Endothelial Cells by a Receptor Cascade Between EPR-1 and PAR-2
Authors: Bono Françoise , Schaeffer Paul , Hérault Jean-Pascal , Michaux Corinne , Nestor Anne-Laure , Guillemot Jean-Claude , Herbert Jean-Marc
Published: June 2011

Abstract—In addition to its pivotal role in hemostasis, factor Xa binds to human umbilical vein endothelial cells through the recognition of a protein called effector cell protease receptor (EPR-1). This interaction is associated with signal transduction, generation of intracellular second messengers, and modulation of cytokine gene expression. Inhibitors of factor Xa catalytic activity block these responses, thus indicating that the factor Xa–dependent event of local proteolysis is absolutely required for cell activation. Because EPR-1 does not contain proteolysis-sensitive sites, we investigated the possibility that signal transduction by factor Xa requires proteolytic activation of a member of the protease-activated receptor (PAR) gene family. Catalytic inactivation of factor Xa by DX9065 suppressed factor Xa–induced increase in cytosolic free Ca2+in endothelial cells (IC50=0.23 μmol/L) but failed to reduce ligand binding to EPR-1. In desensitization experiments, trypsin or the PAR-2–specific activator peptide, SLIGKV, ablated the Ca2+signaling response induced by factor Xa. Conversely, pretreatment of endothelial cells with factor Xa blocked the PAR-2–dependent increase in cytosolic Ca2+signaling, whereas PAR-1–dependent responses were unaffected. Direct cleavage of PAR-2 by factor Xa on endothelial cells was demonstrated by cleavage of a synthetic peptide duplicating the PAR-2 cleavage site and by immunofluorescence with an antibody to a peptide containing the 40–amino acid PAR-2 extracellular extension. These data suggest that factor Xa induces endothelial cell activation via a novel cascade of receptor activation involving docking to EPR-1 and local proteolytic cleavage of PAR-2.
Coimmobilized Native Macromolecular Heparin Proteoglycans Strongly Inhibit Platelet-Collagen Interactions in Flowing Blood
Authors: Kauhanen Petteri , Kovanen Petri T. , Lassila Riitta
Published: June 2011

Abstract
—We coimmobilized mast cell–derived heparin proteoglycans (HEP-PGs) of very high molecular weight (750 kDa) or unfractionated heparin (UFH) on coverslips together with collagen without altering the amount of immobilized collagen. Subsequently, platelet-collagen interactions were studied under both flowing and static conditions in
d
-phenylalanyl-
l
-prolyl-
l
-arginine chloromethyl ketone–anticoagulated blood and platelet-rich plasma (PRP), respectively. At a high shear rate (1600 1/s), the mean platelet deposition (PD) on collagen monomers was 7.5±6.1×10
6
/cm
2
(n=5). When the monomers were coimmobilized with UFH, PD was inhibited by 73% (2.0±1.2×10
6
/cm
2
), whereas HEP-PG completely blocked it (0.42±0.38×10
6
/cm
2
;
P
<0.05). Also, when collagen fibrils were used for coating, HEP-PG significantly inhibited PD. At a low shear rate (200 1/s) and under static conditions in PRP, the inhibitory effect of HEP-PG on PD was less marked. Inhibition of glycoprotein IIb/IIIa did not affect PD on coimmobilized HEP-PG in contrast to coimmobilized UFH or collagen alone. As a sign of inactivation, platelets adhering to the HEP-PG surface released considerably less β-thromboglobulin than did those adhering to pure collagen. In summary, immobilized HEP-PG strongly inhibited PD on collagen by attenuating adhesion-induced platelet activation. The stronger effect on collagen monomers suggests the inhibition of glycoprotein Ia/IIa–mediated activation.
Advanced Atherosclerotic Lesions in the Innominate Artery of the ApoE Knockout Mouse
Authors: Rosenfeld Michael E. , Polinsky Patti , Virmani Renu , Kauser Katalin , Rubanyi Gabor , Schwartz Stephen M.
Published: June 2011

Abstract
—Most previous studies of atherosclerosis in hyperlipidemic mouse models have focused their investigations on lesions within the aorta or aortic sinus in young animals. None of these studies has demonstrated clinically significant advanced lesions. We previously mapped the distribution of lesions throughout the arterial tree of apolipoprotein E knockout (apoE
−/−
) mice between the ages of 24 and 60 weeks. We found that the innominate artery, a small vessel connecting the aortic arch to the right subclavian and right carotid artery, exhibits a highly consistent rate of lesion progression and develops a narrowed vessel characterized by atrophic media and perivascular inflammation. The present study reports the characteristics of advanced lesions in the innominate artery of apoE
−/−
mice aged 42 to 60 weeks. In animals aged 42 to 54 weeks, there is a very high frequency of intraplaque hemorrhage and a fibrotic conversion of necrotic zones accompanied by loss of the fibrous cap. By 60 weeks of age, the lesions are characterized by the presence of collagen-rich fibrofatty nodules often flanked by lateral xanthomas. The processes underlying these changes in the innominate artery of older apoE
−/−
mice could well be a model for the critical processes leading to the breakdown and healing of the human atherosclerotic plaque.
Low Plasma Lycopene Concentration Is Associated With Increased Intima-Media Thickness of the Carotid Artery Wall
Authors: Rissanen Tiina , Voutilainen Sari , Nyyssönen Kristiina , Salonen Riitta , Salonen Jukka T.
Published: June 2011

Abstract
—Although a number of epidemiological studies have evaluated the association between β-carotene and the risk of cardiovascular diseases, there has been little research on the role of lycopene, an acyclic form of β-carotene, with regard to the risk of cardiovascular disease. We investigated the relationship between plasma concentrations of lycopene and intima-media thickness of the common carotid artery wall (CCA-IMT) in 520 middle-aged men and women (aged 45 to 69 years) in eastern Finland. They were examined from 1994 to 1995 at the baseline of the Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) study, a randomized trial concerning the effect of vitamin E and C supplementation on atherosclerotic progression. The subjects were classified into 2 categories according to the median concentration of plasma lycopene (0.12 μmol/L in men and 0.15 μmol/L in women). Mean CCA-IMT of the right and left common carotid arteries was 1.18 mm in men and 0.95 mm in women with plasma lycopene levels lower than the median and 0.97 mm in men (
P
<0.001 for difference) and 0.89 mm in women (
P
=0.027 for difference) with higher levels of plasma lycopene. In ANCOVA adjusting for cardiovascular risk factors and intake of nutrients, in men, low levels of plasma lycopene were associated with a 17.8% increment in CCA-IMT (
P
=0.003 for difference). In women, the difference did not remain significant after the adjustments. We conclude that low plasma lycopene concentrations are associated with early atherosclerosis, manifested as increased CCA-IMT, in middle-aged men living in eastern Finland.
Expression of Tumor Necrosis Factor-α in Cultured Human Endothelial Cells Stimulated With Lipopolysaccharide or Interleukin-1α
Authors: Imaizumi Tadaatsu , Itaya Hiroyuki , Fujita Kazumi , Kudoh Daisuke , Kudoh Seiji , Mori Kazuyuki , Fujimoto Koji , Matsumiya Tomoh , Yoshida Hidemi , Satoh Kei
Published: June 2011

Abstract
—Tumor-necrosis factor-α (TNF-α) is a proinflammatory cytokine with a wide variety of biological effects. The most important source of this cytokine is monocytes/macrophages. It is a potent agonist in the activation of endothelial cells; however, the precise role of endothelial cells as a source of TNF-α is not known. In the present study, we addressed the possibility that TNF-α is produced by cultured human umbilical vein endothelial cells (HUVEC) stimulated with factors such as lipopolysaccharide (LPS) or interleukin-1α (IL-1α). LPS and IL-1α induced expression of TNF-α mRNA in HUVEC. IL-1α induced expression and secretion of TNF-α protein, but LPS did not induce production of TNF-α protein. Most of the TNF-α protein in cell lysate was found in the membrane fraction. The mRNA for TNF-α–converting enzyme (TACE) was expressed in unstimulated HUVEC, and its level was not altered by treatment with LPS or IL-1α. Transfection of HUVEC with full-length cDNA encoding the precursor TNF-α enhanced secretion of TNF-α protein by these cells, and treatment of the cells with a TACE inhibitor reduced the secretion. These results suggest that HUVEC produce TNF-α and have TACE activity. Secreted TNF-α may be involved in autocrine activation of endothelial cells, and TNF-α retained in cell membrane may serve as a juxtacrine system to activate target cells on the endothelial surface.
The Arg123-Tyr166 Central Domain of Human ApoAI Is Critical for Lecithin:Cholesterol Acyltransferase–Induced Hyperalphalipoproteinemia and HDL Remodeling in Transgenic Mice
Authors: Holvoet Paul , De Geest Bart , Van Linthout Sophie , Lox Marleen , Danloy Sophie , Raes Kathleen , Collen Désiré
Published: June 2011

Abstract
—High density lipoprotein (HDL) metabolism and lecithin:cholesterol acyltransferase (LCAT)–induced HDL remodeling were investigated in transgenic mice expressing human apolipoprotein (apo) AI or an apoAI/apoAII chimera in which the Arg123-Tyr166 domain of apoAI was substituted with the Ser12-Ala75 domain of apoAII. Expression of apoAI and of the apoAI/apoAII chimera resulted in a respective 3.5-fold and 2.9-fold increase of HDL cholesterol. Human
LCAT
gene transfer into apoAI-transgenic mice resulted in a 5.1-fold increase of endogenous LCAT activity. This increase was associated with a 2.4-fold increase of the cholesterol ester–to–free cholesterol ratio of HDL, a shift from HDL
3
to HDL
2
, and a 2.4-fold increase of HDL cholesterol levels. Agarose gel electrophoresis revealed that human
LCAT
gene transfer into human apoAI–transgenic mice resulted in an increase of pre-β-HDL and of pre-α-HDL. In contrast, human
LCAT
gene transfer did not affect cholesterol levels and HDL distribution profile in mice expressing the apoAI/apoAII chimera. Mouse LCAT did not “see” a difference between wild-type and mutant human apoAI, whereas human LCAT did, thus localizing the species-specific interaction in the central domain of apoAI. In conclusion, the Arg123-Tyr166 central domain of apoAI is not critical for in vivo lipoprotein association. It is, however, critical for LCAT-induced hyperalphalipoproteinemia and HDL remodeling independent of the lipid-binding properties of apoAI.
Glucosylated Glycerophosphoethanolamines are the Major LDL Glycation Products and Increase LDL Susceptibility to Oxidation
Authors: Ravandi Amir , Kuksis Arnis , Shaikh Nisar A.
Published: June 2011

Abstract
—Glycation of both protein and lipid components is believed to be involved in LDL oxidation. However, the relative importance of lipid and protein glycation in the oxidation process has not been established, and products of lipid glycation have not been isolated. Using glucosylated phosphatidylethanolamine (Glc PtdEtn) prepared synthetically, we have identified glycated diacyl and alkenylacyl species among the ethanolamine phospholipids in LDL. Accumulation of these glycation products in LDL incubated with glucose showed a time- and glucose concentration–dependent increase. LDL specifically enriched with Glc PtdEtn (25 nmol/mg protein) showed increased susceptibility to lipid oxidation when dialyzed against a 5-μmol/L Cu
2+
solution. The presence of this glucosylated lipid resulted in a 5-fold increase in production of phospholipid-bound hydroperoxides and 4-fold increase in phospholipid-bound aldehydes. Inclusion of glucosylated phosphatidylethanolamine in the surface lipid monolayer of the LDL resulted in rapid loss of polyunsaturated cholesteryl esters from the interior of the particle during oxidation. Glycated ethanolamine phospholipids were also isolated and identified from atherosclerotic plaques collected from both diabetic and nondiabetic subjects. The present findings provide direct evidence for the previously proposed causative effect of lipid glycation on LDL oxidation.
Intravascular Ultrasound Combined With Raman Spectroscopy to Localize and Quantify Cholesterol and Calcium Salts in Atherosclerotic Coronary Arteries
Authors: Römer Tjeerd J. , Brennan James F. , Puppels Gerwin J. , Zwinderman Aailko H. , van Duinen Sjoerd G. , van der Laarse Arnoud , van der Steen Anton F. W. , Bom Nicolaas A. , Bruschke Albert V. G.
Published: June 2011

Abstract
—Coronary intravascular ultrasound (IVUS) can assess arterial wall architecture and localize large intravascular deposits, but it does not provide quantitative chemical information, which is essential in the evaluation of atherosclerotic lesions. Previously, it has been shown that Raman spectroscopy can be used to accurately quantify the relative weights of cholesterol, calcium salts, triglycerides, and phospholipids in homogenized arterial tissue. In the present study, we explore some benefits of combining IVUS and Raman spectroscopy to evaluate the intact arterial wall. IVUS images were collected in vitro from human coronary arterial segments in various stages of disease (n=7). The images were divided into radial segments (11 to 28 per image, 332 in total), each of which was classified visually as calcified or noncalcified tissue. The arteries were opened longitudinally, and Raman spectra were collected from locations at 0.5-mm intervals across the arterial luminal circumference. The spectra were used to calculate the chemical composition of the arterial wall at the examined locations. Generally, locations containing large amounts of calcium salts, as determined with Raman spectroscopy, were classified as calcified with IVUS. However, small calcific deposits (<6% of weight) were not readily detected with IVUS. The amounts and location of cholesterol determined with Raman spectroscopy were correlated closely with the presence of cholesterol observed by histochemistry, but these deposits could not be located accurately by IVUS. The combination of Raman spectroscopy and IVUS applied in vitro provides detailed information about the amount and location of calcific deposits and lipid pools in atherosclerotic plaques. Future advances in optical fiber technology may allow simultaneous collection of Raman spectra and IVUS images through the same catheter in vivo.
HMG CoA Reductase Inhibitors Reduce Plasminogen Activator Inhibitor-1 Expression by Human Vascular Smooth Muscle and Endothelial Cells
Authors: Bourcier Todd , Libby Peter
Published: June 2011

Abstract
—The clinical benefit of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) may derive from a qualitative, functional change in atherosclerotic lesions in addition to their lipid-lowering properties. We examined whether statins altered expression of the major determinants of fibrinolytic balance, plasminogen activator inhibitor-1 (PAI-1), and tissue-type plasminogen activator (tPA) in human vascular smooth muscle (SMC) and endothelial (EC) cells. Simvastatin reduced levels of PAI-1 antigen released from SMCs and ECs stimulated with platelet-derived growth factor or transforming growth factor-β (IC
50
≈1 μmol/L). Levels of EC-derived tPA increased 2-fold over the same concentrations of simvastatin that inhibited release of PAI-1. Simvastatin’s inhibitory effect was mimicked by C3 exoenzyme and prevented by geranylgeranyl pyrophosphate, but not by farnesyl pyrophosphate, suggesting the involvement of geranylgeranyl-modified intermediates. Decreased PAI-1 antigen was correlated with reduced mRNA transcription and activity of the PAI-1 promoter. By inhibiting expression of PAI-1 from SMCs and ECs while increasing expression of tPA from ECs, simvastatin may alter the local fibrinolytic balance within the vessel wall toward increased fibrinolytic capacity that, in turn, would reduce thrombotic risk after plaque rupture.
Protective Effect of a Thrombin Receptor (Protease-Activated Receptor 1) Gene Polymorphism Toward Venous Thromboembolism
Authors: Arnaud Emmanuel , Nicaud Viviane , Poirier Odette , Rendu Francine , Alhenc-Gelas Martine , Fiessinger Jean-Noël , Emmerich Joseph , Aiach Martine
Published: June 2011

Abstract
—The human protease-activated receptor 1 (PAR-1) is activated by thrombin at the surface of platelets and endothelial cells, 2 cells that are implicated in hemostasis and thrombosis. We studied the PAR-1 gene in a large case-control study from the Paris Thrombosis Study (PATHROS), and the possible implication of polymorphisms in venous thromboembolism was evaluated. Two polymorphisms were found in the 5′ regulatory region. The first is a C to T transition that is 1426 nucleotides upstream from the translation start site (−1426 C/T), and the second is a 13-bp insertion repeating the preceding −506 5′-CGGCCGCGGGAAG-3′ sequence (−506 I/D, where I indicates insertion and D indicates deletion), a putative
cis
-acting element of the
Ets
family. The third polymorphism is an A to T transversion in the intervening sequence (IVS) that is 14 nucleotides upstream from the exon 2 start site (IVS-14 A/T). The distribution of the 3 polymorphisms was otherwise similar in the 250 cases and the 1214 controls. A noteworthy sex heterogeneity led us to analyze men and women separately with regard to the −506 I/D polymorphism. We found that allele I was less frequent in male cases than in male controls (0.154 versus 0.247,
P
<0.01), with an odds ratio at 0.52 (95% CI 0.32 to 0.82,
P
<0.01). Furthermore, a reduction of prothrombin fragment 1+2 levels was observed in homozygous carriers of allele −506 I (
P
=0.04). Altogether, these data suggested a protective effect in men of −506 I/D polymorphism for venous thromboembolism.
Determinants of Population Changes in Fibrinogen and Factor VII Over 6 Years
Authors: Folsom Aaron R. , Wu Kenneth K. , Rasmussen Mandy , Chambless Lloyd E. , Aleksic Nena , Nieto F. Javier
Published: June 2011

Abstract
—Although numerous cross-sectional studies have identified possible determinants of plasma fibrinogen and factor VII levels, few prospective studies exist. We assessed the longitudinal relation of changes in fibrinogen and factor VII over 6 years with changes to other cardiovascular risk factors in a sample of 440 men and 549 women from the Atherosclerosis Risk in Communities (ARIC) study. Fibrinogen increased more in older participants, those with or who developed diabetes, those who at any time smoked, and those whose plasma HDL cholesterol or triglycerides decreased and increased less in female participants who started hormonal replacement therapy. Factor VII coagulant activity increased more in younger participants, women, those who gained greater weight or developed diabetes, those who quit smoking, those in whom plasma triglycerides decreased, and female participants who received hormonal replacement therapy. Thus, our longitudinal data suggest with some exceptions that adverse changes in cardiovascular risk factors are accompanied by increases in plasma levels of fibrinogen and factor VII.
Enhanced Expression of Osteopontin in Human Diabetic Artery and Analysis of Its Functional Role in Accelerated Atherogenesis
Authors: Takemoto Minoru , Yokote Koutaro , Nishimura Motonobu , Shigematsu Takashi , Hasegawa Toshio , Kon Shigeyuki , Uede Toshimitsu , Matsumoto Taro , Saito Yasushi , Mori Seijiro
Published: June 2011

Abstract
—We have previously reported that high glucose stimulates osteopontin (OPN) expression through protein kinase C–dependent pathways as well as hexosamine pathways in cultured rat aortic smooth muscle cells. The finding prompted us to study in vivo expression of OPN in diabetes mellitus. In the present study, we found by immunohistochemistry that medial layers of the carotid arteries of streptozotocin-induced diabetic rats and the forearm arteries of diabetic patients stained positively for OPN antibodies, whereas the staining from arteries of control rats and nondiabetic patients was negative. We also found that OPN stimulated the migration and enhanced platelet-derived growth factor (PDGF)-mediated DNA synthesis of cultured rat aortic smooth muscle cells. OPN and PDGF synergistically activated focal adhesion kinase as well as extracellular signal–regulated kinase; this finding seems to explain the OPN-induced enhancement of PDGF-mediated DNA synthesis. Taken together, our present results raise a possibility that OPN plays a role in the development of diabetic vascular complications.
Nitric Oxide Induces the Synthesis of Vascular Endothelial Growth Factor by Rat Vascular Smooth Muscle Cells
Authors: Dulak Józef , Józkowicz Alicja , Dembinska-Kiec Aldona , Guevara Ibeth , Zdzienicka Anna , Zmudzinska-Grochot Danuta , Florek Izabela , Wójtowicz Anna , Szuba Andrzej , Cooke John P.
Published: June 2011

Abstract
—Vascular endothelial growth factor (VEGF) is known to induce the release of nitric oxide (NO) from endothelial cells. However, the effect of NO on VEGF synthesis is not clear. Accordingly, the effect of endogenous and exogenous NO on VEGF synthesis by rat vascular smooth muscle cells (VSMCs) was investigated. Two in vitro models were used: (1) VSMCs stimulated to produce NO by treatment with interleukin (IL)-1β (10 ng/mL) and (2) VSMCs lipotransfected with pKecNOS plasmid, containing the endothelial constitutive NO synthase (ecNOS) cDNA. The synthesis of NO was inhibited by
N
ω
-nitro-
l
-arginine methyl ester (L-NAME, 2 to 5 mmol/L) or diaminohydroxypyrimidine (DAHP, 2.5 to 5 mmol/L), inhibitors of NOS and GTP cyclohydrolase I, respectively. Some cells treated with L-NAME or DAHP were supplemented with
l
-arginine (10 mmol/L) or tetrahydrobiopterin (BH
4
; 100 μmol/L), respectively. In addition, we studied the effect of sodium nitroprusside (SNP; 10 and 100 μmol/L) and chemically related compounds, potassium ferrocyanide and ferricyanide, on VEGF generation. IL-1β induced iNOS expression and NO generation and significantly upregulated VEGF mRNA expression and protein synthesis. L-NAME and DAHP totally inhibited NO generation and decreased the IL-1β–upregulated VEGF synthesis by 30% to 40%. Supplementation with
l
-arginine or BH
4
increased NO generation by L-NAME– or DAHP-treated cells, and VEGF synthesis was augmented by addition of BH
4
. The cells generating NO after pKecNOS transfection released significantly higher amounts of VEGF than cells transfected with control plasmids. Inhibition of NO generation by L-NAME decreased VEGF synthesis. In contrast to the effect of endogenous NO, we observed the inhibition of VEGF synthesis in the presence of high (10 or 100 μmol/L) concentrations of SNP. This effect was mimicked by chemically related ferricyanide and ferrocyanide compounds, suggesting that the inhibitory effect of sodium nitroprusside may be mediated by an NO-independent mechanism. The results indicate that endogenous NO enhances VEGF synthesis. The positive interaction between endogenous NO and VEGF may have implications for endothelial regeneration after balloon angioplasty and for angiogenesis.
Diabetes Mellitus
Authors: Kuller Lewis H. , Velentgas Priscilla , Barzilay Joshua , Beauchamp Norman J. , O’Leary Daniel H. , Savage Peter J.
Published: June 2011

Abstract
—Previously diagnosed diabetes mellitus, newly diagnosed diabetes mellitus, and impaired glucose tolerance are important determinants of the risk of clinical cardiovascular disease (CVD). We have evaluated the relation of patients with subclinical CVD, diabetes, and impaired glucose tolerance and “normal” subjects and the risk of clinical CVD in the Cardiovascular Health Study. Diabetes (1343), impaired glucose tolerance (1433), and normal (2421) were defined by World Health Organization criteria at baseline in 1989 to 1990. The average follow-up was 6.4 years (mean age 73 years). Diabetics had a higher prevalence of clinical and subclinical CVD at baseline. Compared with diabetes in the absence of subclinical disease, the presence of subclinical CVD and diabetes was associated with significant increased adjusted relative risk of death (1.5, CI 0.93 to 2.41), relative risk of incident coronary heart disease (1.99, CI 1.25 to 3.19), and incident myocardial infarction (1.93, CI 0.96 to 3.91). The risk of clinical events was greater for participants with a history of diabetes compared with newly diagnosed diabetics at baseline. Compared with nondiabetic nonhypertensive subjects without subclinical disease, patients with a combination of diabetes, hypertension, and subclinical disease had a 12-fold increased risk of stroke. Fasting blood glucose levels were a weak predictor of incident coronary heart disease as were most other risk factors. Subclinical CVD was the primary determinant of clinical CVD among diabetics in the Cardiovascular Health Study.
Regulated von Willebrand Factor Secretion Is Associated With Agonist-Specific Patterns of Cytoskeletal Remodeling in Cultured Endothelial Cells
Authors: Vischer Ulrich M. , Barth Holger , Wollheim Claes B.
Published: June 2011

Abstract
—von Willebrand factor (vWF), an adhesive glycoprotein involved in primary hemostasis, is stored and released from endothelial secretory granules called Weibel-Palade bodies. Regulated secretion occurs in reaction either to [Ca
2+
]
i
-raising agents (histamine or thrombin) or to cAMP-raising agents (epinephrine, adenosine, or forskolin). We investigated the pattern of release and the cytoskeletal requirements for secretion in response to these 2 classes of agonists. Secretion induced by [Ca
2+
]
i
-raising agents involves peripheral and central granules and is inhibited by colchicine-induced microtubule disruption. It is accompanied by Rho-dependent stress fiber formation and cell retraction. Secretion and remodeling occur in the same individual cells. However, secretion is potentiated by cytochalasin E and C3 toxin, indicating that stress fiber formation antagonizes vWF secretion. In contrast, vWF secretion induced by cAMP-raising agents involves the release of only peripheral granules (implying less vWF release on a per cell basis) and is not inhibited by microtubule disruption. cAMP-mediated secretion is accompanied by disruption of stress fibers, strengthening of the cortical actin rim, and preservation of cell-cell contacts. It is unaffected by cytochalasins or C3 toxin. In contrast to [Ca
2+
]
i
-raising agents, cAMP-raising agents induce secretion without cell retraction/intercellular gap formation. Thus, they are likely to play a physiological role in the regulation of endothelial vWF secretion and, therefore, of plasma vWF levels.
Expression of Macrophage (Mφ) Scavenger Receptor, CD36, in Cultured Human Aortic Smooth Muscle Cells in Association With Expression of Peroxisome Proliferator Activated Receptor-γ, Which Regulates Gain of Mφ-Like Phenotype In Vitro, and Its Implication in Atherogenesis
Authors: Matsumoto Kengo , Hirano Ken-ichi , Nozaki Shuichi , Takamoto Akiko , Nishida Makoto , Nakagawa-Toyama Yumiko , Janabi Mohamed Yakub , Ohya Takeshi , Yamashita Shizuya , Matsuzawa Yuji
Published: June 2011

Abstract
—CD36 is one of the major receptors for oxidized low density lipoproteins belonging to macrophage (Mφ) scavenger receptor (SR) class B and is thought to play an important role in the foam cell formation from monocyte-Mφ in the atherosclerotic lesions. Although it has been hypothesized that smooth muscle cells (SMCs) may be the other origin of foam cells in vivo, supporting data are still very limited. In the present study, we have tested the expression of a variety of SRs, including CD36, in 8 lots of primary human aortic SMCs (HASMCs) explanted from 8 different donors. Functional CD36 was expressed in cultured HASMCs, and the levels of expression were widely ranged between the lots. SR class A (SR-A) was expressed abundantly in CD36-negative lots. Other Mφ markers, such as CD32 and CD68, were expressed in all lots tested. These data suggest that the cultured HASMCs gained an Mφ-like phenotype. To determine the mechanism for the above-described phenotypic change, we have tested the expression of a nuclear receptor, peroxisome proliferator activated receptor-γ, in those cells. This nuclear receptor was abundantly expressed in CD36-positive lots, whereas c-
fms
was expressed abundantly in CD36-negative/SR-A–positive lots. The synthetic ligand of peroxisome proliferator activated receptor-γ, troglitazone, upregulated the expression of CD36 only in CD36-positive lots. These observations demonstrate that cultured HASMCs can gain an Mφ-like phenotype, possibly classified by the expression of CD36 or SR-A. The present study may support the possibilities of transformation of HASMCs into foam cells in vivo.
Rapid Restoration of Normal Endothelial Functions in Genetically Hyperlipidemic Mice by a Synthetic Mediator of Reverse Lipid Transport
Authors: Williams Kevin Jon , Scalia Rosario , Mazany Kirstin D. , Rodrigueza Wendi V. , Lefer Allan M.
Published: June 2011

Abstract
—Endothelial dysfunction is a major pathophysiological consequence of hypercholesterolemia and other conditions. We examined whether a synthetic mediator of lipid transport from peripheral tissues to the liver (ie, the “reverse” pathway) could restore normal endothelial function in vivo. Using assays of macrovascular and microvascular function, we found that genetically hypercholesterolemic apolipoprotein E knockout mice exhibited key endothelial impairments. Treatment of the mice for 1 week with daily intravenous bolus injections of large “empty” phospholipid vesicles, which accelerate the reverse pathway in vivo, restored endothelium-dependent relaxation, leukocyte adherence, and endothelial expression of vascular cell adhesion molecule-1 to normal or nearly normal levels. These changes occurred despite the long-standing hyperlipidemia of the animals and the persistence of high serum concentrations of cholesterol-rich atherogenic lipoproteins during the treatment. Our results indicate that dysfunctional macrovascular and microvascular endothelium in apolipoprotein E knockout mice can recover relatively quickly in vivo and that accelerated reverse lipid transport may be a useful therapy.