bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Expression of Lectinlike Oxidized Low Density Lipoprotein Receptor-1 in Initial Atherosclerotic Lesions of Watanabe Heritable Hyperlipidemic Rabbits
Authors: Chen Mingyi , Kakutani Makoto , Minami Manabu , Kataoka Hiroharu , Kume Noriaki , Narumiya Shuh , Kita Toru , Masaki Tomoh , Sawamura Tatsuya
Published: June 2011

Abstract
—A novel lectinlike oxidized low density lipoprotein receptor-1 (LOX-1) was recently identified in bovine aortic endothelial cells. It is strongly suggested to have a potential role in the initiation and development of atherosclerosis. In this study, we have isolated cDNA clones encoding the rabbit homologue of LOX-1 by screening a rabbit placenta cDNA library. In amino acid sequence and domain structure organization, the rabbit LOX-1 is highly conserved with the human counterpart. Transfection of rabbit LOX-1 cDNA to HEK-293 cells confers on them the activity to bind and internalize oxidized low density lipoprotein. Rabbit LOX-1 was identified as a 45-kDa protein by Western blot analysis with a specific monoclonal antibody. Notably, analyses by reverse transcription–polymerase chain reaction and Western blot revealed that LOX-1 was accumulated in 8-week-old Watanabe heritable hyperlipidemic rabbit aortas compared with normal rabbit aortas. Immunostaining confirmed that the augmented expression of LOX-1 was primarily localized within the intima at the earliest stages of atherogenesis. The most prominent staining was in the endothelial cells of lesions. Furthermore, the distinctive staining of LOX-1 was identified in the endothelium of nonlesion areas of Watanabe heritable hyperlipidemic rabbit aortas. Taken together, these findings support the possibility that LOX-1 might be involved in the initiation of atherosclerosis.
p53, p21
WAF1/CIP1
, and MDM2 Involvement in the Proliferation and Apoptosis in an In Vitro Model of Conditionally Immortalized Human Vascular Smooth Muscle Cells
Authors: Hsieh J.-Kuang , Kletsas Dimitris , Clunn Gerard , Hughes Alun D. , Schachter Michael , Demoliou-Mason Catherine
Published: June 2011

Abstract
—Using an in vitro model of a conditionally immortalized cell line, we have investigated how human vascular smooth muscle cells (VSMCs) are affected by the expression of simian virus 40 (SV40) large T antigen (LT antigen), which binds to cell cycle regulators such as the tumor suppressor protein p53. Cells were obtained after infection of saphenous vein-derived VSMCs with a nonreplicative retroviral vector containing a temperature-sensitive mutant of SV40 LT antigen and were shown to have maintained some characteristics and responses of VSMCs. Under permissive-temperature conditions (36°C), the increased rate of cell proliferation was shown to be associated with expression of LT antigen and with LT antigen binding to and inactivation of p53. p53 inactivation failed to block apoptosis induced by serum withdrawal or UV irradiation. Downregulation of LT antigen expression at a nonpermissive temperature (39°C) was shown to be associated with growth arrest, increased expression of the cell cycle inhibitor p21
WAF1/CIP1
, increased murine double minute-2 promoter activity, and differential expression of murine double minute-2 gene products, suggesting that p53-induced transcription/transactivation may be involved in VSMC cycle control but not necessarily in apoptosis. The established SMC line HVTs-SM1 may be a useful model for study of the processes involved in myointimal hyperplasia and cellular aging, as well as for the study of cell cycle control in general.
Intronic Polymorphism in the Fatty Acid Transport Protein 1 Gene Is Associated With Increased Plasma Triglyceride Levels in a French Population
Authors: Meirhaeghe Aline , Martin Geneviève , Nemoto Masami , Deeb Samir , Cottel Dominique , Auwerx Johan , Amouyel Philippe , Helbecque Nicole
Published: June 2011

Abstract
—Fatty acids play important biological roles in cells. The precise mechanism whereby fatty acids cross the plasma membrane is still poorly understood. They can cross membranes because of their hydrophobic properties and/or be transported by specific proteins. Recently, a gene coding for fatty acid transport protein 1 (FATP1), an integral plasma membrane protein implicated in this process, was cloned in humans. We screened the gene by single-strand conformation polymorphism analysis and detected an A/G polymorphism in intron 8. We analyzed the potential relations of this genetic polymorphism with various obesity markers and with plasma lipid profiles in a random sample of 1144 French subjects aged 35 to 64 years. We detected statistically significant associations between this
FATP1
A/G polymorphism and an increase in plasma triglyceride levels, mainly in women. These results suggest that genetic variability in the
FATP1
gene may affect lipid metabolism, especially in women, and reinforce the potential implication of FATP1 in lipid homeostasis.
Functional Characterization of 4 Polymorphisms in Promoter Region of Hepatic Lipase Gene
Authors: van ′t Hooft Ferdinand M. , Lundahl Björn , Ragogna Francesca , Karpe Fredrik , Olivecrona Gunilla , Hamsten Anders
Published: June 2011

Abstract
—Hepatic lipase (HL) is a lipolytic enzyme involved in the metabolism of plasma lipoproteins, especially high density lipoproteins. Association studies have provided strong evidence for relations of common mutations in the promoter region of the HL gene to postheparin plasma HL activity and the plasma high density lipoprotein cholesterol concentration, but the functional relevance of these polymorphisms has not been evaluated to date. We analyzed the physiological significance of 4 common polymorphisms (−250G/A, −514C/T, −710T/C, and −763A/G, all in strong linkage disequilibrium) in the promoter of the HL gene by use of electrophoretic mobility shift assays and transient transfection studies in HepG2 cells. No consistent evidence was found for a significant contribution of any of these polymorphisms to the basal rate of transcription of the HL gene. These data suggest that the 4 polymorphisms in the promoter region of the HL gene are in linkage disequilibrium with ≥1 as-yet-unknown functional polymorphisms in the HL gene locus with a significant effect on HL metabolism and/or enzymatic activity.
Noncholesterol Sterols and Cholesterol Lowering by Long-Term Simvastatin Treatment in Coronary Patients
Authors: Miettinen T. A. , Strandberg T. E. , Gylling H.
Published: June 2011

Abstract
—Coronary patients with low baseline ratios of serum cholestanol and plant sterols to cholesterol (indicating low cholesterol absorption) but not those with high ratios (high absorption) experienced reduced recurrences of coronary events during simvastatin treatment in the Scandinavian Simvastatin Survival Study. Thus, in the present study, serum cholesterol, its precursor sterols (reflecting cholesterol synthesis), plant sterols (campesterol and sitosterol), and cholestanol were measured before and during a 5-year period of placebo treatment (n=433) and simvastatin treatment (n=434) in patients from a subgroup of the Scandinavian Simvastatin Survival Study to determine whether changes in cholesterol synthesis and serum levels were related to cholesterol absorption. Serum cholesterol level was unchanged, the ratios of cholesterol precursor sterols to cholesterol were decreased, and the ratios of plant sterols to cholesterol were increased in relation to increasing baseline ratios of cholestanol quartiles. The latter predicted 5-year ratios and simvastatin-induced reductions of the precursor sterols, with the lowering of the ratios (cholesterol synthesis reduction) being almost twice higher in the lowest versus the highest quartile. The ratios of plant sterols, especially campesterol, to cholesterol were markedly increased during simvastatin treatment, mostly in subjects with the highest baseline cholestanol quartiles. Simvastatin reduced serum cholesterol more (
P
=0.003) in the lowest versus the highest cholestanol quartile during the 5-year treatment period. The results show for the first time that baseline cholesterol metabolism, measured by serum noncholesterol sterols, predicts the effectiveness of simvastatin in reducing cholesterol synthesis and serum levels of cholesterol. The drug suppresses the synthesis of cholesterol markedly more effectively in subjects with high than with low baseline synthesis but reduces respective serum cholesterol levels less markedly than synthesis. Subjects with high cholesterol absorption and low synthesis may need a combination therapy to lower more effectively their serum cholesterol levels and prevent an increase in the levels of plant sterols.
Influence of Fibrin Network Conformation and Fibrin Fiber Diameter on Fibrinolysis Speed
Authors: Collet J. P. , Park D. , Lesty C. , Soria J. , Soria C. , Montalescot G. , Weisel J. W.
Published: June 2011

Abstract
—Abnormal fibrin architecture is thought to be a determinant factor of hypofibrinolysis. However, because of the lack of structural knowledge of the process of fibrin digestion, relationships between fibrin architecture and hypofibrinolysis remain controversial. To elucidate further structural and dynamic changes occurring during fibrinolysis, cross-linked plasma fibrin was labeled with colloidal gold particles, and fibrinolysis was followed by confocal microscopy. Morphological changes were characterized at fibrin network and fiber levels. The observation of a progressive disaggregation of the fibrin fibers emphasizes that fibrinolysis proceeds by transverse cutting rather than by progressive cleavage uniformly around the fiber. Plasma fibrin clots with a tight fibrin conformation made of thin fibers were dissolved at a slower rate than those with a loose fibrin conformation made of thicker (coarse) fibers, although the overall fibrin content remained constant. Unexpectedly, thin fibers were cleaved at a faster rate than thick ones. A dynamic study of FITC–recombinant tissue plasminogen activator distribution within the fibrin matrix during the course of fibrinolysis showed that the binding front was broader in coarse fibrin clots and moved more rapidly than that of fine plasma fibrin clots. These dynamic and structural approaches to fibrin digestion at the network and the fiber levels reveal aspects of the physical process of clot lysis. Furthermore, these results provide a clear explanation for the hypofibrinolysis related to a defective fibrin architecture as described in venous thromboembolism and in premature coronary artery disease.
Factor V Antigen Levels and Venous Thrombosis
Authors: Kamphuisen P. W. , Rosendaal F. R. , Eikenboom J. C. J. , Bos R. , Bertina R. M.
Published: June 2011

Abstract
—Clotting factor V has a dual function in coagulation: after activation, procoagulant factor V stimulates the formation of thrombin, whereas anticoagulant factor V acts as a cofactor for activated protein C (APC) in the degradation of factor VIII/VIIIa, thereby reducing thrombin formation. In the present study, we evaluated whether plasma factor V levels, either decreased or increased, are associated with venous thrombosis. High procoagulant factor V levels may enhance prothrombinase activity and increase the thrombosis risk. Low anticoagulant factor V levels could reduce APC-cofactor activity in the factor VIII inactivation (APC-resistant phenotype), which might also promote thrombosis. Low factor V levels in combination with factor V Leiden could lead to a more severe APC-resistant phenotype (pseudohomozygous APC resistance). To address these issues, we have measured factor V antigen (factor V:Ag) levels in 474 patients with thrombosis and 474 control subjects that were part of the Leiden Thrombophilia Study (LETS). Factor V:Ag levels increased by 7.6 U/dL for every successive 10 years of age. Mean factor V:Ag levels were 134 (range 41 to 305) U/dL in patients and 132 (range 47 to 302) U/dL in controls. Neither high nor low factor V:Ag levels were associated with venous thrombosis. We found that factor V:Ag and factor VIII antigen levels in plasma were correlated, but factor V did not modify the thrombotic risk of high factor VIII levels. The normalized APC ratio was not influenced by the factor V:Ag level in subjects with or without factor V Leiden. We conclude that neither low nor high factor V:Ag levels are associated with venous thrombosis and that factor V:Ag levels do not mediate the thrombotic risk associated with high factor VIII levels.
Infection and Atherosclerosis
Authors: Epstein Stephen E. , Zhu Jianhui , Burnett Mary Susan , Zhou Yi Fu , Vercellotti Gregory , Hajjar David
Published: June 2011

Abstract
—Infection has been implicated as a cause of atherosclerosis since the first half of the 19th century. Over the years, sporadic publications have appeared in the literature reflecting a persistent but relatively low level of research activity in this area. In the last decade, however, publications relating to this topic have increased markedly. And very recently, new epidemiological and mechanistic data relating infection to several different diseases, including atherosclerosis, have appeared, stimulating the emergence of important paradigm shifts in how we think about the causes of chronic disease. The following article reviews some of these newer concepts as they relate to a possible role of infection in atherosclerosis.
Interactions of Oxidants With Vascular Signaling Systems
Authors: Wolin Michael S.
Published: June 2011

Abstract
—Individual reactive oxygen species (ROS) and oxidation products of NO interact with vascular signaling mechanisms in ways that appear to have fundamental roles in the control of vascular physiological and pathophysiological function. The activities of ROS-producing systems (including various NADPH and NADH oxidases, xanthine oxidase, and NO synthase) in endothelium and/or vascular smooth muscle are controlled by receptor activation, oxygen tension, metabolic processes, and physiological forces associated with blood pressure and flow. This review focuses on how the chemical properties and metabolic sensing interactions of individual ROS (including superoxide anion, hydrogen peroxide, and peroxynitrite) interact with cellular regulatory systems to produce vascular responses. These species appear to often function through producing selective alterations in individual heme or thiol redox–regulated systems (including guanylate cyclase, cyclooxygenase, mitochondrial electron transport, and tyrosine phosphatases) to initiate physiological responses through signaling pathways that control phospholipases, protein kinases, ion channels, contractile proteins, and gene expression.
Vascular Protection
Authors: Zachary Ian , Mathur Anthony , Yla-Herttuala Seppo , Martin John
Published: June 2011

Abstract
—There is widespread interest in the use of the angiogenic cytokine, vascular endothelial growth factor (VEGF), for the treatment of cardiovascular disease. The main paradigm for VEGF cardiovascular therapy is the stimulation of “therapeutic angiogenesis” in ischemic myocardial and peripheral vascular limb disease. In this review, approaches to VEGF therapy based on the therapeutic angiogenesis model are critically assessed, and the alternative mechanism of vascular protection is advanced. Vascular protection is defined as the VEGF-induced enhancement of endothelial functions that mediate the inhibition of vascular smooth muscle cell proliferation, enhanced endothelial cell survival, suppression of thrombosis, and anti-inflammatory effects. VEGF-induced synthesis of NO and prostacyclin are both likely to be key mediators of VEGF-dependent vascular protection. Investigation into vascular protection should help us to gain insight into the underlying mechanisms of the cardiovascular actions of VEGF and should prove valuable in the development of novel therapeutic approaches based on local VEGF gene delivery.
Impaired Superoxide Production Due to a Deficiency in Phagocyte NADPH Oxidase Fails to Inhibit Atherosclerosis in Mice
Authors: Kirk Elizabeth A. , Dinauer Mary C. , Rosen Henry , Chait Alan , Heinecke Jay W. , LeBoeuf Renée C.
Published: June 2011

Abstract
—Superoxide, the reduced form of molecular oxygen, has been implicated in the genesis of vascular disease. One potential mechanism involves oxidation of low density lipoprotein into an atherogenic particle. A second involves reaction with nitric oxide to generate peroxynitrite, a highly oxidizing intermediate. A third involves regulation of signal transduction in artery wall cells. One well-characterized pathway for superoxide production resides in macrophages, the cellular hallmark of the early atherosclerotic lesion. Macrophages contain a membrane-bound NADPH oxidase that reduces oxygen to superoxide. In the current studies, we used mice that are deficient in the gp91-phox subunit of the NADPH oxidase–a model of chronic granulomatous disease (CGD)–to explore the role of superoxide in atherosclerotic vascular disease. Wild-type and CGD mice on the C57BL/6 background received a high-fat diet for 20 weeks to induce hypercholesterolemia. At the end of this period, the 2 strains of mice had comparable plasma lipid levels, and their atherosclerotic lesions were similar in size. We also crossed CGD mice with apolipoprotein E–deficient (apoE−/−) mice to generate spontaneously hypercholesterolemic animals that lacked functional NADPH oxidase. After 24 weeks, the CGD-apoE−/− animals had lower plasma cholesterol and triglyceride levels than did the apoE−/− animals, but there was no difference in the extent of atherosclerotic plaque. Our findings suggest that superoxide generated by the NADPH oxidase of phagocytes does not promote atherosclerosis in mice with either diet-induced or genetic forms of hypercholesterolemia.
Genetic Variation in Human Stromelysin Gene Promoter and Common Carotid Geometry in Healthy Male Subjects
Authors: Gnasso Agostino , Motti Corradino , Irace Concetta , Carallo Claudio , Liberatoscioli Laura , Bernardini Sergio , Massoud Renato , Mattioli Pier Luigi , Federici Giorgio , Cortese Claudio
Published: June 2011

Abstract
—A common variant in the promoter of the human stromelysin gene, causing reduced enzyme expression, has been associated with the progression of coronary atherosclerosis. On the other hand, increased stromelysin activity may promote plaque rupture. The present study was undertaken to investigate the relationship between the genetic variation in the human stromelysin gene promoter and common carotid geometry. Forty-two healthy male subjects without major coronary heart disease risk factors were investigated. The polymorphism in the stromelysin gene promoter was studied through polymerase chain reaction amplification with the use of mutagenic primers. Age, blood pressure, lipids, glucose, viscosity, and body mass index were similar in homozygotes for the 5A allele (5A/5A), heterozygotes (5A/6A), and homozygotes for the 6A allele (6A/6A). Serum matrix metalloproteinase-3 levels did not differ significantly among genotypes. Common carotid diameters and intima-media thickness, measured by noninvasive ultrasonography, were significantly larger in 6A/6A subjects (for respective 6A/6A, 5A/6A, and 5A/5A subjects, diameter at the R wave was 0.63±0.09, 0.55±0.06, and 0.53±0.04 cm [mean±SD],
P
<0.005 by ANOVA; intima-media thickness was 765±116, 670±116, and 630±92 μm [mean±SD],
P
<0.05 by ANOVA). Wall shear stress, calculated as blood velocity×blood viscosity/internal diameter, was significantly lower in 6A/6A subjects (for respective 6A/6A, 5A/6A, and 5A/5A subjects, mean wall shear stress was 10.4±2.9, 13.5±3.5, and 12.6±1.9 dyne/cm
2
[mean±SD],
P
<0.05 by ANOVA).The results demonstrate that the gene polymorphism in the promoter region of stromelysin is associated with structural and functional characteristics of the common carotid artery in healthy male subjects without major risk factors for atherosclerosis. Individuals with the 6A/6A genotype (associated with lower enzyme activity) show a triad of events, namely, increased wall thickness, enlarged arterial lumen, and local reduction of wall shear stress, which might predispose them to atherosclerotic plaque localization.
Are Retinal Arteriolar Abnormalities Related to Atherosclerosis?
Authors: Klein Ronald , Sharrett A. Richey , Klein Barbara E. K. , Chambless Lloyd E. , Cooper Lawton S. , Hubbard Larry D. , Evans Greg
Published: June 2011

Abstract
—The objective of this study was to describe associations of retinal arteriolar abnormalities with clinical and subclinical manifestations of atherosclerosis and a broad group of risk factors for vascular disease. A biracial population of 8772 adults (aged 48 to 72 years) living in 4 communities was examined from 1993 to 1995 were studied for that purpose. Retinal arteriovenous nicking and focal arteriolar narrowing were determined by light-box grading of a 45° fundus photograph by use of a standardized protocol. Diameters of arterioles and venules were measured in digitized photographs, and a summary arteriolar-to-venular ratio was derived as an index of generalized arteriolar narrowing. Focal arteriolar narrowing was associated only with hypertension. Generalized arteriolar narrowing was associated with carotid plaque but not with any other evidence of atherosclerosis, either clinical (cardiovascular disease or stroke) or subclinical (carotid or popliteal artery thickness or lower limb obstructive disease), or with plasma cholesterol. It was also associated with smoking, with inflammatory markers (white blood cell count, fibrinogen, and reduced albumin), and with the triglyceride and high density lipoprotein cholesterol changes associated with inflammation. Arteriovenous nicking was inconsistently associated with subclinical atherosclerosis. It was not associated with cardiovascular disease, stroke, or plasma cholesterol. Arteriovenous nicking was associated with markers of inflammation and vascular endothelial dysfunction (von Willebrand factor and factor VIII). Arteriolar narrowing and nicking appear to be related to hypertension and inflammatory factors. Nicking may also be related to endothelial dysfunction. Results suggest that these arteriolar changes are pathologically distinct from atherosclerosis. Including their measurement in population studies may permit evaluation of the independent contribution of arteriolar disease to various ischemic diseases of the heart, brain, and other organs.
Molecular Characterization and Localization of the NAD(P)H Oxidase Components gp91-
phox
and p22-
phox
in Endothelial Cells
Authors: Bayraktutan Ulvi , Blayney Lynda , Shah Ajay M.
Published: June 2011

Abstract
—The production of reactive oxygen species (ROS) within endothelial cells may have several effects, including alterations in the activity of paracrine factors, gene expression, apoptosis, and cellular injury. Recent studies indicate that a phagocyte-type NAD(P)H oxidase is a major source of endothelial ROS. In contrast to the high-output phagocytic oxidase, the endothelial enzyme has much lower biochemical activity and a different substrate specificity (NADH>NADPH). In the present study, we (1) cloned and characterized the cDNA and predicted amino acid structures of the 2 major subunits of rat coronary microvascular endothelial cell NAD(P)H oxidase, gp91-
phox
and p22-
phox
; (2) undertook a detailed comparison with phagocytic NADPH oxidase sequences; and (3) studied the subcellular location of these subunits in endothelial cells. Although these studies revealed an overall high degree of homology (>90%) between the endothelial and phagocytic oxidase subunits, the endothelial gp91-
phox
sequence has potentially important differences in a putative NADPH-binding domain and in putative glycosylation sites. In addition, the subcellular location of the endothelial gp91-
phox
and p22-
phox
subunits is significantly different from that reported for the neutrophil oxidase, in that they are predominantly intracellular and collocated in the vicinity of the endoplasmic reticulum. This first detailed characterization of gp91-
phox
and p22-
phox
structure and location in endothelial cells provides new data that may account, in part, for the differences in function between the phagocytic and endothelial NAD(P)H oxidases.
Oxidized LDL–Induced NF-κB Activation and Subsequent Expression of Proinflammatory Genes Are Defective in Monocyte-Derived Macrophages From CD36-Deficient Patients
Authors: Janabi Mohamed , Yamashita Shizuya , Hirano Ken-ichi , Sakai Naohiko , Hiraoka Hisatayo , Matsumoto Kengo , Zhang Zhongyan , Nozaki Shuichi , Matsuzawa Yuji
Published: June 2011

Abstract
—CD36 is 1 of the class B scavenger receptor expressed on monocytes, monocyte-derived macrophages (Mφ), platelets, and adipocytes. In our previous studies, we reported that the uptake of oxidized low density lipoproteins (OxLDLs) is reduced by ≈50% in Mφ from CD36-deficient patients compared with that in control subjects. Recently, we have shown that CD36 is highly expressed in human atherosclerotic aorta. Possibilities have been raised that besides the wide distribution and multifunctional characteristics of CD36, this molecule may also be involved in the mediation of intracellular signaling. The aim of the present study was to elucidate the role of CD36 in cytokine secretion and to investigate the CD36-mediated intracellular signaling stimulated by OxLDL. On addition of OxLDL or thrombospondin-1, the Mφ from CD36-deficient patients secreted significantly less amounts of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) compared with those from controls. RNase protection assay with multiprobe template sets demonstrated that after incubation with OxLDL, the mRNAs of a variety of cytokines, including genes encoding IL-1Ra, IL-1β, IL-6, TNF-α and -β, and interferon (IFN)-γ and -β, were significantly lower in the Mφ of patients. The addition of antibody against CD36 attenuated this OxLDL-induced response in controls. We also observed a reduced response in nuclear factor-κB (NF-κB) activity in OxLDL-stimulated Mφ from CD36-deficient patients. Unlike OxLDL, stimulation by lipopolysaccharide induced an increase in NF-κB activity in Mφ from CD36-deficient patients, suggesting that lipopolysaccharide-mediated signaling was conserved. These results demonstrate that in addition to the reduced OxLDL uptake that we reported previously, CD36-deficient patients may also have an impaired response of OxLDL-induced NF-κB activation and subsequent cytokine expression.
Arterial Mechanical Changes in Children With Familial Hypercholesterolemia
Authors: Yacine Aggoun  , Bonnet Damien , Sidi Daniel , Girardet Jean Philippe , Brucker Eric , Polak Michel , Safar Michel E. , Levy Bernard I.
Published: June 2011

Abstract
—Atherosclerosis is preceded by a phase of changes in the arterial wall that could have functional consequences even before the appearance of atheromatous changes. We hypothesized that early alterations of the mechanical properties of the arterial wall could precede clinical and echographic modifications. We used an automatic, computerized, ultrasonic procedure to evaluate geometric and mechanical characteristics of the common carotid artery (CCA) in normotensive children with primary familial class IIA hypercholesterolemia (FH; n=30; mean±SD age, 11±2 years old; mean±SD systolic/diastolic blood pressure, 109±9/55±7 mm Hg). These subjects were compared with age-matched, nonobese control subjects (n=27; 11±3 years old; 112±10/55±7 mm Hg). Noninvasive ultrasonic measurements were performed by the same investigator to measure the CCA luminal systolic and diastolic diameters and intima-media thickness (IMT). The cross-sectional compliance, cross-sectional distensibility, and the incremental elastic modulus of the CCA wall were then calculated. Finally, we assessed the degree of reactive hyperemia in the brachial artery produced after distal cuff occlusion and release. The changes in brachial arterial diameter in response to reactive hyperemia (endothelium-dependent dilation) and to glyceryltrinitrate (endothelium-independent dilation) were then measured. In patients with FH, we observed a significant reduction of systodiastolic variations in diameter (by 20%,
P
<0.001) without a significant difference in IMT. Cross-sectional compliance and cross-sectional distensibility were significantly reduced in FH subjects (by 15%,
P
<0.05 and 19%,
P
<0.01, respectively). In parallel, the incremental elastic modulus was significantly increased (by 27%,
P
<0.01) in children with FH. No correlation was evident between the carotid incremental modulus and either IMT or plasma low density lipoprotein cholesterol level. There was no difference in diameter of the brachial artery at rest in control and FH subjects (3.0±0.5 versus 3.0±0.4 mm). The reactive hyperemia and glyceryltrinitrate dilation were also similar in the 2 groups. However, the flow-mediated dilation of the brachial artery was smaller in the FH subjects (4.2±2.9%) than in controls (9.0±3.1%,
P
<0.001). In FH, endothelium-dependent dilation was negatively correlated with the plasma low density lipoprotein cholesterol level (
P
<0.04). These results indicate that increased stiffness of the CCA wall in children with FH is independent of blood pressure and could be related to endothelial dysfunction. Thus, alterations in CCA wall mechanics could be early and easily measurable markers of atheromatous changes in the arterial wall.
Long-Term Effects of Vitamin E, Vitamin C, and Combined Supplementation on Urinary 7-Hydro-8-Oxo-2′-Deoxyguanosine, Serum Cholesterol Oxidation Products, and Oxidation Resistance of Lipids in Nondepleted Men
Authors: Porkkala-Sarataho Elina , Salonen Jukka T. , Nyyssönen Kristiina , Kaikkonen Jari , Salonen Riitta , Ristonmaa Ulla , Diczfalusy Ulf , Brigelius-Flohe Regina , Loft Steffen , Poulsen Henrik E.
Published: June 2011

Abstract
—We studied the long-term effects of vitamins E and C and their combination on lipid peroxidation in vivo and in vitro. The Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) trial is a double-masked placebo-controlled randomized clinical trial to study the effects of vitamin C (500 mg of slow release ascorbate per day), vitamin E (182 mg of RRR-α-tocopherol acetate per day), and the combination of both antioxidants. Lipid peroxidation measurements were carried out for 48 male participants at entry and at 12 and 36 months. Compared with placebo, vitamin E and the vitamin combination increased plasma lipid–standardized α-tocopherol during the first 12 months by 68.2% and 65.2% (
P
<0.001 for both), respectively, and reduced serum 7β-hydroxycholesterol by 50.4% (
P
=0.013) and 44.0% (
P
=0.041), respectively. The net change of lipid standardized α-tocopherol was 63.8% after 36 months of vitamin E supplementation and 43.3% for the combination. Vitamin C supplementation elevated plasma total ascorbate level by 30.1% (
P
=0.043) in 12 months and by 91.1% (
P
=0.001) in 36 months. Neither vitamin E, vitamin C, nor the combination influenced the urinary excretion rate of 7-hydro-8-oxo-2′-deoxyguanosine or the antioxidative capacity of plasma. Vitamin E and the combination of vitamins E and C enhanced the oxidation resistance of isolated lipoproteins and total serum lipids. Our data indicate that long-term supplementation of nondepleted men with a reasonable dose of vitamin E alone or in combination with slow release vitamin C reduces lipid peroxidation in vitro and in vivo, whereas a relatively high dose of vitamin C alone does not.
Reduction of Aortic Wall Motion Inhibits Hypertension-Mediated Experimental Atherosclerosis
Authors: Tropea Bradford I. , Schwarzacher Severin P. , Chang Albert , Asvar Chris , Huie Phil , Sibley Richard K. , Zarins Christopher K.
Published: June 2011

Abstract
—Hypertension is a well-known risk factor for coronary artery disease and carotid and lower extremity occlusive disease. Surgically induced hypertension in hypercholesterolemic animals results in increased aortic wall motion and increased plaque formation. We tested the hypothesis that reduction in aortic wall motion, despite continued hypertension, could reduce plaque formation. New Zealand White rabbits (n=26) underwent thoracic aortic banding to induce hypertension and were fed an atherogenic diet for 3 weeks. In 13 rabbits, a segment of aorta proximal to an aortic band was externally wrapped to reduce wall motion. All animals were fed an atherogenic diet for 3 weeks. Four groups were studied: 1, coarctation control (no wrap, n=7); 2, coarctation with loose wrap (n=6); 3, coarctation with firm wrap (n=7); and 4, control (noncoarcted, n=6). Wall motion, blood pressure, and pulse pressure were measured at standard reference sites proximal and distal to the coarctation by use of intravascular ultrasound. Quantitative morphometry was used to measure intimal plaque. Mean arterial pressure and cyclic aortic wall motion were equally increased proximal to the aortic coarctation in all 3 coarcted rabbit groups compared with the control group (
P
<0.001). Wall motion in the segment of aorta under the loose and firm wraps was no different from the control value. The external wrap significantly reduced intimal thickening in the 4 groups by the following amounts: group 1, 0.30±0.03 mm
2
; group 2, 0.06±0.02 mm
2
; group 3, 0.04±0.02 mm
2
; and group 4, 0.01±0.01 mm
2
(
P
<0.001). Localized inhibition of aortic wall motion in the lesion-prone hypertensive aorta resulted in significant reduction in intimal plaque formation. These data suggest that arterial wall cyclic motion may stimulate cellular proliferation and lipid uptake in experimental atherosclerosis.
Serum Homocysteine Levels Are Associated With the Development of (Micro)albuminuria
Authors: Jager Agnes , Kostense Piet J. , Nijpels Giel , Dekker Jacqueline M. , Heine Robert J. , Bouter Lex M. , Donker Ab J. M. , Stehouwer Coen D. A.
Published: June 2011

Abstract
—Microalbuminuria is a strong indicator of the risk of future cardiovascular disease and renal dysfunction. Slightly increased levels of homocysteine, an independent risk factor for atherothrombotic disease, have recently been found to be associated with the presence of (micro)albuminuria. However, it is unknown whether increased homocysteine levels precede the occurrence of (micro)albuminuria. Normoalbuminuric subjects (n=316, 66 with non–insulin-dependent diabetes mellitus [NIDDM]) of an age-stratified, sex-stratified, and glucose tolerance–stratified sample of a population-based cohort study were investigated at baseline and after a mean follow-up duration of 6.1 years. Development of (micro)albuminuria was defined as a mean albumin-to-creatinine ratio >2.0 mg/mmol at the follow-up examination. The cumulative incidence of (micro)albuminuria was 14.0% (9.7 % to 18.3%) among nondiabetic subjects and 22.7% (12.9% to 32.5%) among NIDDM patients. Age-adjusted, sex-adjusted, and glucose tolerance status–adjusted logistic regression analyses showed development of (micro)albuminuria to be significantly associated with baseline homocysteine levels >19.0 μmol/L compared with homocysteine levels <9.1 μmol/L (odds ratio [OR] 5.1, 95% CI 1.1 to 23.0). For homocysteine levels of 9.1 to 14.0 μmol/L and 14.1 to 19.0 μmol/L, the values were OR 1.2 (95% CI 0.5 to 3.0) and OR 1.8 (95% CI 0.6 to 5.3), respectively. Additional adjustment for baseline insulin resistance, blood pressure, body mass index, presence of cardiovascular disease and retinopathy, current smoking, or estimates of glomerular filtration rate did not materially affect the results. Substituting homocysteine levels as a continuous variable for categories of homocysteine levels showed that a 5-μmol/L increase of the homocysteine level was associated with an increased risk of developing (micro)albuminuria (OR 1.38, 95% CI 0.97 to 1.95) . Analyses performed in nondiabetic and diabetic subjects separately gave similar results among nondiabetic subjects. Among diabetic subjects, the association between homocysteine level and (micro)albuminuria could not be estimated, because there was an insufficient number of diabetic subjects with high homocysteine levels. Hyperhomocysteinemia is an independent determinant of the development of (micro)albuminuria among nondiabetic subjects, even after adjustment for estimates of glomerular filtration rate. We could neither confirm nor reject an association between homocysteine levels and the development of (micro)albuminuria among NIDDM subjects. These data suggest that homocysteine may play a pathophysiological role in the development of (micro)albuminuria.
Induction of Endothelial-Leukocyte Interaction by Interferon-γ Requires Coactivation of Nuclear Factor-κB
Authors: De Caterina Raffaele , Bourcier Todd , Laufs Ulrich , La Fata Vito , Lazzerini Guido , Neish Andrew S. , Libby Peter , Liao James K.
Published: June 2011

Abstract
—To determine whether nuclear factor (NF)-κB is necessary to confer endothelial cell responsiveness to interferon (INF)-γ in terms of vascular cell adhesion molecule (VCAM)-1 expression and leukocyte adhesion, human endothelial cells were treated with IFN-γ in the presence of low concentrations (LCs) of interleukin (IL)-1α (≤100 pg/mL), which activates NF-κB but does not induce VCAM-1 expression. Although IFN-γ induced major histocompatibility complex class II antigen expression and although a high concentration of IL-1α (10 ng/mL) induced leukocyte adhesion and VCAM-1 expression, neither IFN-γ nor LC IL-1α was able to induce VCAM-1 expression or leukocyte adhesion. However, the combination of IFN-γ and LC IL-1α induced VCAM-1 expression and increased leukocyte adhesion (67% and 49% of high-concentration IL-1α, respectively). Electrophoretic mobility shift assays and immunoblotting of nuclear extracts showed that IFN-γ activated signal transducers and activators of transcription (STAT)-1α and interferon regulatory factor (IRF)-1 but not NF-κB, whereas LC IL-1α activated NF-κB but not STAT-1α or IRF-1. Nuclear run-on studies showed that LC IL-1α is necessary but not sufficient for inducing VCAM-1 gene transcription and that the combination of IFN-γ and LC IL-1α is required for full VCAM-1 gene transcription. These findings suggest that factors that activate NF-κB can synergize with IFN-γ in promoting endothelial-leukocyte interaction.
Dysregulation of Extracellular Adenosine Levels by Vascular Smooth Muscle Cells From Spontaneously Hypertensive Rats
Authors: Dubey Raghvendra K. , Mi Zaichuan , Gillespie Delbert G. , Jackson Edwin K.
Published: June 2011

Abstract
—The objective of this investigation was to determine whether the regulation of extracellular adenosine levels by smooth muscle cells (SMCs) from conduit arteries (aorta) and resistance microvessels (renal arterioles) is different in spontaneously hypertensive rats (SHR) versus normotensive Wistar-Kyoto (WKY) rats. Basal extracellular adenosine levels were decreased in cultured aortic and arteriolar SHR SMCs, and the increase in extracellular adenosine levels induced by stimulation of the cAMP-adenosine pathway was less in aortic and arteriolar SHR SMCs. Extracellular adenosine levels were lower in SHR SMCs, however, even when the cAMP-adenosine pathway was inhibited with 3-isobutyl-1-methylxanthine. Inhibition of adenosine kinase with iodotubercidin and inhibition of adenosine deaminase with erythro-9-(2-hydroxy-3-nonyl) adenine increased extracellular adenosine; however, only inhibition of adenosine deaminase equalized extracellular adenosine levels in SHR versus WKY SMCs. Membrane-disrupted SHR SMCs metabolized exogenous adenosine faster than WKY SMCs did, and this difference was abolished by inhibition of adenosine deaminase but not adenosine kinase. SHR SMCs demonstrated a greater proliferative response than WKY SMCs. This enhanced proliferative response was not blocked by adenosine per se or inhibition of adenosine kinase but was blocked by inhibition of adenosine deaminase and by 2-chloroadenosine (adenosine deaminase–resistant adenosine analogue). We conclude that dysregulation of extracellular adenosine levels exists in SHR SMCs, that this dysregulation is not due to a defect in the cAMP-adenosine pathway but rather to enhanced activity of adenosine deaminase, and that the dysregulation of extracellular adenosine mediates the enhanced proliferative response of SHR SMCs.
Metabolic and Lifestyle Determinants of Postprandial Lipemia Differ From Those of Fasting Triglycerides
Authors: Sharrett A. R. , Heiss G. , Chambless L. E. , Boerwinkle E. , Coady S. A. , Folsom A. R. , Patsch W.
Published: June 2011

Abstract
—Despite the reported association of lipoprotein responses to a fatty meal with atherosclerosis, little is known about the determinants of these responses. Plasma triglyceride, retinyl palmitate, and apolipoprotein B-48 responses to a standardized fatty meal containing a vitamin A marker were measured in 602 Atherosclerosis Risk in Communities (ARIC) study participants. To focus on postprandial responses specifically, which have been reported to be related to atherosclerosis independently of fasting triglycerides, analyses for determinants of postprandial responses were adjusted for fasting triglycerides. Major determinants of fasting triglycerides, namely, diabetes, obesity, other factors related to insulin resistance, and male sex, were not independently associated with postprandial responses. Fasting triglycerides were the strongest predictor of postprandial lipids, but independent of triglycerides, the predictors of postprandial responses were smoking, diet, creatinine, and alcohol. Smokers had substantially increased retinyl palmitate and apolipoprotein B-48 responses, indicators of chylomicrons and their remnants. Persons who consume more calories or ω3 fatty acids had reduced chylomicron responses. Triglyceride responses were associated positively with serum creatinine levels and negatively with moderate alcohol consumption. Thus, determinants of fasting and postprandial lipids differ. The independent atherogenic influence of postprandial lipids may relate more to smoking and diet than to obesity and insulin resistance.
Cytoskeletal Effects of Rho-Like Small Guanine Nucleotide–Binding Proteins in the Vascular System
Authors: van Nieuw Amerongen Geerten P. , van Hinsbergh Victor W.M.
Published: June 2011

Abstract
—Rho-like small GTPases, with their main representatives (Rho, Rac, and Cdc42), have been recognized in the past decade as key regulators of the F-actin cytoskeleton. Rho-like small GTPases are now known to play a major role in vascular processes caused by changes in the actin cytoskeleton, such as smooth muscle cell contraction, endothelial permeability, platelet activation, and leukocyte migration. Data are now accumulating regarding the involvement of Rho GTPases in vascular disorders associated with vascular remodeling, altered cell contractility, and cell migration. The unraveling of signal transduction pathways used by the Rho-like GTPases revealed many upstream regulators and downstream effector molecules, and their number is still growing. An important action of Rho, Rac, and Cdc42 is their ability to regulate the phosphorylation status of the myosin light chain, a major regulator of actin-myosin interaction. Present knowledge of the Rho-like small GTPases has resulted in the development of promising new strategies for the treatment of many vascular disorders, including hypertension, vasospasms, and vascular leakage.
Troglitazone Inhibits Formation of Early Atherosclerotic Lesions in Diabetic and Nondiabetic Low Density Lipoprotein Receptor–Deficient Mice
Authors: Collins Alan R. , Meehan Woerner P. , Kintscher Ulrich , Jackson Simon , Wakino Shu , Noh Grace , Palinski Wulf , Hsueh Willa A. , Law Ronald E.
Published: June 2011

Abstract
—Peroxisome proliferator–activated receptor-γ (PPARγ) is a ligand-activated nuclear receptor expressed in all of the major cell types found in atherosclerotic lesions: monocytes/macrophages, endothelial cells, and smooth muscle cells. In vitro, PPARγ ligands inhibit cell proliferation and migration, 2 processes critical for vascular lesion formation. In contrast to these putative antiatherogenic activities, PPARγ has been shown in vitro to upregulate the CD36 scavenger receptor, which could promote foam cell formation. Thus, it is unclear what impact PPARγ activation will have on the development and progression of atherosclerosis. This issue is important because thiazolidinediones, which are ligands for PPARγ, have recently been approved for the treatment of type 2 diabetes, a state of accelerated atherosclerosis. We report herein that the PPARγ ligand, troglitazone, inhibited lesion formation in male low density lipoprotein receptor–deficient mice fed either a high-fat diet, which also induces type 2 diabetes, or a high-fructose diet. Troglitazone decreased the accumulation of macrophages in intimal xanthomas, consistent with our in vitro observation that troglitazone and another thiazolidinedione, rosiglitazone, inhibited monocyte chemoattractant protein-1–directed transendothelial migration of monocytes. Although troglitazone had some beneficial effects on metabolic risk factors (in particular, a reduction of insulin levels in the diabetic model), none of the systemic cardiovascular risk factors was consistently improved in either model. These observations suggest that the inhibition of early atherosclerotic lesion formation by troglitazone may result, at least in part, from direct effects of PPARγ activation in the artery wall.
Troglitazone Inhibits Atherosclerosis in Apolipoprotein E–Knockout Mice
Authors: Chen Zhong , Ishibashi Shun , Perrey Stéphane , Osuga Jun-ichi , Gotoda Takanari , Kitamine Tetsuya , Tamura Yoshiaki , Okazaki Hiroaki , Yahagi Naoya , Iizuka Yoko , Shionoiri Futoshi , Ohashi Ken , Harada Kenji , Shimano Hitoshi , Nagai Ryozo , Yamada Nobuhiro
Published: June 2011

Abstract
—Atherosclerotic coronary heart disease is a common complication of the insulin resistance syndrome that can occur with or without diabetes mellitus. Thiazolidinediones (TZDs), which are insulin-sensitizing antidiabetic agents, can modulate the development of atherosclerosis not only by changing the systemic metabolic conditions associated with insulin resistance but also by exerting direct effects on vascular wall cells that express peroxisome proliferator–activated receptor-γ (PPAR-γ), a nuclear receptor for TZDs. Here we show that troglitazone, a TZD, significantly inhibited fatty streak lesion formation in apolipoprotein E–knockout mice fed a high-fat diet (en face aortic surface lesion areas were 6.9±2.5% vs 12.7±4.7%,
P
<0.05; cross-sectional lesion areas were 191 974±102 911 μm
2
vs 351 738±175 597 μm
2
,
P
<0.05; n=10). Troglitazone attenuated hyperinsulinemic hyperglycemia and increased high density lipoprotein cholesterol levels. In the aorta, troglitazone markedly increased the mRNA levels of CD36, a scavenger receptor for oxidized low density lipoprotein, presumably by upregulating its expression, at least in part, in the macrophage foam cells. These results indicate that troglitazone potently inhibits fatty streak lesion formation by modulating both metabolic extracellular environments and arterial wall cell functions.