tbuckley/cabot-search huggingface dataset:
Abstract 5460 Heat Shock Protein 27 Over-Expression in Hematopoietic Cells is Atheroprotective and Anti-Inflammatory
Authors: Tara A Seibert, Yong-Xiang Chen, Melissa McNulty, XiaoLing Zhoa, Kevin Sun, Katey Rayner, Edward R O’Brien
Journal: Circulation (2009)

Previously, we demonstrated that Heat shock protein 27 (HSP27) shows diminished expression with progression of human coronary atherosclerosis [ATVB 2005]. Moreover, we have shown that global over-expression of HSP27 (HSP27 o/e ) protects against the development of atherosclerosis in ApoE −/− mice in part via binding to Scavenger Receptor-A [Circ Res 2008]. More recent experiments reveal that macrophage apoptosis is less frequent in advanced (12 wk) lesions from apoE −/− HSP27 o/e mice and highlight macrophage specific anti-inflammatory protective mechanisms. The purpose of this study was to determine if blood-borne cells (e.g., mononuclear cells) are sufficient and required for the HSP27 atheroprotective phenotype in female ApoE −/− mice. Methods/Results: Female ApoE −/− mice (~10 Weeks old and ≥ 18.5 g), underwent μ -irradiation to eliminate endogenous bone marrow before receiving bone marrow from either female ApoE −/− or ApoE −/− HSP27 o/e donors. After 6 weeks of recovery recipients were placed on a high fat/cholesterol diet for 4 weeks to induce atherosclerosis before being euthanized. ApoE −/− mice receiving bone marrow from ApoE −/− HSP27 o/e had detectable levels of HSP27 mRNA in liver and spleen. In addition, the HA tag of the over-expression construct was detectable in liver sections and HSP27 was measured in the serum from mice receiving the ApoE −/− HSP27 o/e bone marrow. Over-expression of HSP27 in cells of hematopoietic origin resulted in a 52% reduction in aortic en face lesion burden (p=0.005) and a 32% reduction in the lesion area found in aortic sinus cross-sections (p=0.02). The macrophage content of lesions in both murine populations was similar. In vitro bone marrow derived macrophages from ApoE −/− HSP27 o/e mice had a 2.7-fold decrease in oxidized LDL uptake after 24 hrs (p=0.002) and were less adherent to LPS activated HUVECs (p&lt;0.05) when compared to ApoE −/− derived macrophages. In conclusion, the over-expression of HSP27 in bone marrow derived cells is sufficient and necessary to provide atheroprotection in ApoE −/− mice and points to a central role for HSP27 in reducing the inflammatory milieu of atherosclerotic lesions.
Abstract 5438: Directed Differentiation of Endothelial Cells From Coronary Artery Disease (CAD) Patients-derived iPS Cells
Authors: Sinae Kim, Changwon Park, Ji Woong Han, Sung-Whan Kim, Hyongbum Kim, Yong Jin Choi, Eugine Lee, Riyaz Patel, In-Hyun Park, George Q. Daley, Arshed Quyyumi, Young-sup Yoon
Journal: Circulation (2009)

Background. We recently generated Induced pluripotent stem (iPS) cells generated from peripheral blood mononuclear cells of coronary artery disease (CAD) patients. In this study, we sought to differentiate these iPS cells into endothelial cells (ECs), and to confirm their vasculogenic potential in vivo using multiple animal models. Methods and Results. In these experiments, iPS cells were spontaneously differentiated through embryoid body (EB) formation and were sorted for KDR using FACS. Next, we further cultured these KDR + cells for 21 days and sorted for KDR and CD31. These KDR + CD31 + cells showed a higher rate (~70%) of double positivity for UEA1 lectin and ac-LDL uptake. The KDR + CD31 + cells expressed endothelial specific proteins such as VE-cadherin and von Willebrand factor (vWF) under immunohistochemical examination, formed tubes when cultured in Matrigel, and expressed EC-specific genes ( KDR, CD31, CD34, eNOS, VE-cadherin, vWF ) as shown by qRT-PCR analysis. In this culture condition, the EC phenotype was maintained &gt; 2 months. Next, to verify their EC characteristics in vivo and provide bona fide evidence of EC commitment of iPS cells, Matrigel plug assay and a hindlimb ischemia model were employed. First, we injected a mixture of Matrigel and the KDR + CD31 + cells labeled with a red fluorescent dye, DiI, into the backs of athymic mice subcutaneously. Two months later, the mice were perfused with an endothelial cell marker, isolectin B4 (ILB4) to stain functional endothelium. The injected cells gave rise to vascular structures and were stained positive for ILB4. Second, we surgically induced hindlimb ischemia in nude mice and injected the KDR + CD31 + cells labeled with DiI into the hindlimb muscles immediately after the surgery. After sacrificing the mice nine days later, muscles were harvested and the tissues were subjected to immunohistochemistry with ILB4. Injected KDR + CD31 + cells expressed ILB4 and were incorporated into vascular structures, suggesting vasculogenesis. In conclusion. iPS cells derived from CAD patients can generate functionally competent ECs in vivo, Together the present study suggest that endothelially differentiated cells from iPS cells can be used therapeutically in an autologous manner to treat tissue ischemia.
Abstract 5224: CB1 Receptor Inhibition Leads to Decreased Vascular AT1 Receptor Expression, Inhibition of Oxidative Stress and Improved Endothelial Function
Authors: Vedat Tiyerili, Sebastian Zimmer, Suzin Jung, Kerstin Wassmann, Georg Nickenig, Sven Wassmann
Journal: Circulation (2009)

Inhibition of the cannabinoid receptor CB1 (CB1-R) exerts numerous effects such as modulation of blood pressure, insulin sensitivity and lipid concentrations. However, direct vascular effects of CB1-R inhibition remain unclear. Methods and Results: CB1-R expression was validated in vascular smooth muscle cells (VSMC) and aortic tissue of mice (real-time RT-PCR). Treatment of cultured VSMC with the selective CB1-R antagonist rimonabant resulted in reduced angiotensin II (ang II)-mediated reactive oxygen species (ROS) production (DCF fluorescence) and NADPH oxidase activity (lucigenin-enhanced chemiluminescence). Because rimonabant inhibited ang II-induced but not basal ROS production, and ang II activates NADPH oxidase through ang II type-1 receptor (AT1-R) stimulation, we analyzed AT1-R expression in VSMC. CB1-R inhibition with rimonabant or AM251 led to down-regulation of AT1-R protein expression (Western blot), stimulation with the CB1-R agonist CP55,940 resulted in AT1-R up-regulation, and co-incubation with CP55,940 abolished the effect of rimonabant, indicating that AT1-R expression is directly regulated by the CB1-R. The expression of rac1 and MnSOD was not affected. VSMC showed no significant expression of the CB2-R under basal conditions (real-time PCR, Western blot), and CB2-R inhibition had no impact on AT1-R expression in VSMC. To investigate the relevance of CB1-R inhibition in vivo, apolipoprotein E-deficient (ApoE−/−) mice were treated with cholesterol-rich diet and rimonabant or vehicle for 7 weeks. Consistent with the in vitro findings, CB1-R inhibition decreased AT1-R expression (real-time RT-PCR, Western blot), NADPH oxidase activity, and ROS production (L-012 chemiluminescence) in the aortic wall. Importantly, CB1-R inhibition improved endothelium-dependent vasodilation of isolated aortic segments (organ chamber experiments), indicating a functional relevance in vivo. Conclusions: CB1-R inhibition leads to decreased vascular AT1-R expression, NADPH oxidase activity and ROS production in vitro and in vivo. This antioxidative effect is associated with improved endothelial function in ApoE−/− mice, indicating beneficial direct vascular effects of CB1-R inhibition.
Abstract 4888: A Novel Role of Kruppel-like Factor 2 (KLF2) in Regulating Endothelial Barrier Function
Authors: Zhiyong Lin, Viswanath Natesan, Hong Shi, Daiji Kawanami, Caili Hao, Ganapati H Mahabaleshwar, G. Brandon Atkins, James H Finigan, Mukesh K Jain
Journal: Circulation (2009)

Background : Selective permeability is a life sustaining function of endothelial cells. Defects in permeability are implicated in several diseases such as sepsis, ischemia reperfusion injury and diabetes. Previous studies by our group and others have identified KLF2 as a molecular switch regulating endothelial gene expression and function. However the role of KLF2 in vascular permeability remains unknown. Methods and Results : Adenoviral overexpression of KLF2 in HUVECs strongly attenuated the increase of endothelial permeability by thrombin (1U/ml), histamine (200 μ M) and hydrogen peroxide (500 μ M) as measured by two independent assays – transendothelial electrical resistance (TER) and FITC-Dextran passage using a transwell system. Conversely, KLF2 deficiency in HUVECs (by siRNA knockdown) and primary mouse endothelial cells (derived from KLF2 +/+ and KLF2+/− mice) exhibited a marked increase in thrombin-induced permeability. To assess the effect of KLF2 in vascular permeability in vivo, we measured the leakage of Evans Blue dye into interstitial tissues of the mouse ear (expressed as μ g of dye/mg of ear tissue) after treatment with mustard oil. Consistent with our in vitro observation, by comparison to KLF2+/+ mice, KLF2 +/− mice exhibited a significantly higher degree of vascular leak (53.4±2.68 μ g/mg in KLF2+/+ versus 72.36±4.71 μ g/mg in KLF2+/−, p&lt;0.05). Mechanistically, our gain and loss-of-function studies indicate that KLF2 differentially affects key endothelial targets that regulate barrier function. Specifically, KLF2 markedly attenuated agonist- induced increase in Myosin Light Chain (MLC) phosphorylation (a key signaling molecule that promotes endothelial barrier permeability), increased Rac1 activation (a small GTPase that has been shown to confer barrier protection properties), and increased the expression of occludin and zona occludens-1 (tight junction proteins that promote barrier function). Conclusions : These observations identify KLF2 as an essential regulator of endothelial barrier function. Targeting of KLF2 function may be beneficial in disorders characterized by excessive vascular permeability such as sepsis. This research has received full or partial funding support from the American Heart Association, Founders Affiliate (Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, Vermont).
Abstract 5125: Elevated Serum Brain Natriuretic Peptide Level Predicts the Presence of the Left Atrial Appendage Dysfunction in Patients With Acute Ischemic Stroke
Authors: Harutoshi Tamura, Tetsu Watanabe, Shintaro Sasaki, Satoshi Nishiyama, Hiroki Takahashi, Takanori Arimoto, Tetsuro Shishido, Takehiko Miyashita, Takuya Miyamoto, Joji Nitobe, Isao Kubota
Journal: Circulation (2009)

Background: It is well known that the left atrial appendage (LAA) dysfunction plays an important role in the occurrence of the cardioembolic stroke. It has been reported that the atrium is the main source of brain natriuretic peptide (BNP) in atrial fibrillation patients without heart failure. Therefore, we hypothesized that serum BNP levels are sensitive predictor for LAA dysfunction and thrombus formation in patients with acute ischemic stroke. Methods: We performed trans-thoracic and esophageal echocardiography within 7 days after the onset (male, n=64, 69±11 years old; female, n=38, 68±15 years old) and measured serum hemostatic markers and BNP in 103 patients with ischemic stroke. No patients had history of heart failure. Results: LAA thrombus was detected in 8 patients (36%) among 22 patients with atrial fibrillation. Even in 3 patients (4%) among 80 patients with sinus rhythm, LAA thrombus was detected. There were no significant differences in left ventricular end-diastolic dimension (LVDd), and the ratio of the early diastolic trans-mitral inflow velocity (E) to mitral annular velocity (E′) between patients with and without LAA thrombus (LVDd, 49±6 vs. 47±5 mm; E/E′, 8.6±1.3 vs. 7.2±0.9). Serum BNP levels were markedly higher in patients with LAA thrombus formation than in those without it (191 (128 –278) vs. 39 (13–100) pg/ml, P&lt;0.01). Furthermore, in patients with sinus rhythm (n=80), the BNP levels were significantly correlated with LAA peak emptying flow velocity (R=−0.34, P&lt;0.01). The multivariate logistic regression analysis revealed that BNP &gt;120 was an independent predictor of LAA thrombus formation (odds ratio, 13.50; 95% confidence interval, 2.482–73.40; P=0.0026). Conclusions: The BNP levels were correlated with LAA peak emptying flow velocity. The elevated BNP level could be used as a non-invasive surrogate maker to predict LAA dysfunction and thrombus formation in patients with acute ischemic stroke.
Abstract 5118: Cardiac <i>β</i> 1-Adrenergic Receptor Blockade Promotes Angiogenesis in the Post-Ischemic Failing Heart via Activation of VEGF- and Akt-dependent Signalling Pathways
Authors: Carmela Zincarelli, Giuseppe Rengo, Luca Golino, Anastasios Lymperopoulos, Giovanna Giuseppina Altobelli, Vincenzo Cimini, Massimo Marchese, Claudio De Lucia, Walter J Koch, Dario Leosco
Journal: Circulation (2009)

Impaired angiogenesis in the post-myocardial infarction (MI) heart, contributes to the progression to heart failure (HF). The inhibition of vascular endothelial growth factor (VEGF) signaling has been shown to induce the transition from compensatory hypertrophy to failure. In the present study, we investigated whether treatment with β 1- adrenergic receptor ( β -AR) blockade Bisoprolol (B) may reactivate VEGF-dependent angiogenesis and counteract maladaptive remodeling in HF. 4 weeks from surgically-induced MI, 40 male Sprague Dawley rats, were randomized to receive B (10 mg/Kg/d, for 10 weeks) or vehicle. 10 sham-operated rats were also included in the study. Echocardiography revealed reduced cardiac LV diameters in B-treated compared to vehicle-treated rats. Moreover, B treatment was associated with increased LV capillary and arteriolar density, and with increased in vivo coronary perfusion and reserve. Importantly, 10 days after B treatment was started, increased cardiac VEGF expression and Akt and eNOS activation were observed by comparing B-treated to drug-untreated hearts. The concomitant administration of B and the mTOR inhibitor Rapamycin (R), which inhibits Akt activation, was associated with increased LV dilatation and dysfunction, and decreased myocardial capillary and arteriolar density compared to B treatment alone. Finally, to test whether the pro-angiogenic effects of B act via activation of VEGF expression, rats were intravenously injected with adenoviral vector encoding a decoy VEGF receptor (Ad-Flk) or a control adenovirus (Ad-C), at the start of the treatment. After 10 weeks from the start of the treatments, histological analysis revealed reduced capillary and arteriolar density, and coronary perfusion in B-treated+Ad-Flk compared to B-treated+Ad-C. Moreover, VEGF inhibition counteracted the positive effects of B on cardiac remodeling and function. In conclusion, β 1-AR selective blockade promotes angiogenesis in HF hearts via activation of VEGF- and Akt-dependent signaling pathways. The β -blocker-induced enhancement of vascular bed prevents progression from adaptive to maladaptive remodeling in the failing myocardium, thus counteracting the progressive dysfunction of the failing heart. This research has received full or partial funding support from the American Heart Association, Great Rivers Affiliate (Delaware, Kentucky, Ohio, Pennsylvania &amp; West Virginia).
Abstract 5140: The Transcription Factor Nrf2 is a Novel Target for the Treatment of Myocardial Ischemia-Reperfusion Injury
Authors: John W Calvert, D. B Grinsfelder, Marah Elston, Christopher B Pattillo, Christopher G Kevil, David J Lefer
Journal: Circulation (2009)

Background: Nuclear-factor-E2-related factor 2 (Nrf2), a member of the NF-E2 family of nuclear basic leucine zipper transcription factors, regulates the gene expression of a number of proteins that attenuate pro-oxidative and pro-apoptotic signaling pathways. The role of Nrf2 in myocardial ischemia-reperfusion (MI/R) injury has not been investigated. Therefore, we evaluated its role using an in vivo murine model of myocardial ischemia-reperfusion (MI/R) injury. Methods: Mice deficient in Nrf2 (Nrf2 KO; ICR background) were subjected to 30 minutes of MI followed by reperfusion for 24 hr, at which time the extent of myocardial infarction per area-at-risk (INF/AAR) or per left ventricle (INF/LV) was evaluated with TTC and serum troponin-I levels were measured. In separate studies, C57BL/6J mice were also subjected to MI followed by 24 hr of reperfusion. The known activator of Nrf2, sulforaphane (5 mg/kg) or vehicle was administered 30 min prior to myocardial ischemia. Results: Myocardial injury following I/R was found to be exacerbated in Nrf2 KO mice compared with Wild-Type mice, as evidenced by a 61% increase in infarct size relative to the area-at-risk (Inf/AAR; 43±7 vs. 27±0.1%, p&lt;0.01), a 59% increase in INF relative to the entire left ventricle (Inf/LV; 25±4 vs. 14.9±1.6%, p&lt;0.05), and an increase in circulating Troponin-I levels from 26±5.2 to 52.4±9 ng/mL (p&lt;0.05). In contrast, the administration of sulforaphane induced myocardial Nrf2 nuclear translocation and reduced infarct size by 40%. Conclusions: These data reveal that Nrf2 is an endogenous cardioprotective-signaling molecule that represents a novel target for the treatment of acute myocardial infarction.
Abstract 4907: LDL-loaded Macrophages Convert Smooth Muscle Cells Into Foam Cell Like Cells by Direct Transport of LDL/cholesterol During Cell-cell-contact
Authors: Soenke Weinert, David M Poitz, Joerg Herold, Alexander Schmeisser, Ruth H Strasser, Ruediger Braun-Dullaeus
Journal: Circulation (2009)

Lipid-loaded macrophages [MP] and vascular smooth muscle cells [VSMC] are key players of atherosclerotic plaque development. However, little is known about their interaction. We hypothesized that MP modulate VSMC behavior directly by cell cell contact. Monocyte-derived MP were exposed to fluorescence-labeled acetylated LDL [FL-LDL] prior co-culture. Semi-confluent VSMC were co-cultured with the FL-LDL-tagged MP in a ratio of 1:3, respectively. Immune cytochemistry revealed that up to 20% of sm-actin positive cells (VSMC) gained Fl-LDL particles. Transfer of the particles was abolished by cell separation in a trans-well co-culture system. Time-lapse microscopy demonstrated that the VSMC acquired the FL-LDL from MP within hours. No phagocytosis of apoptotic bodies was involved in this process. 3D high magnification microscopy demonstrated that, within 24 h, the entire cytosol of single VSMC was filled with FL-LDL. FL-LDL/FL-cholesterol complexes were also transferred and resulted in cholesterol positive lipid droplet formation in VSMC. Usage of the acidotropic fluorescence dye LysoTracker ™ demonstrated that some Fl-LDL was bioactive and reached the acidic lysosomes of VSMC. Marking all lysosomes with a fusion protein of LAMP1 and RFP demonstrated that the remaining FL-LDL was located in non acidic lysosomes. VSMC were then infected with a virus coding for a Rab5a-GFP fusion protein to mark all early endosomes. In contrast to endothelial cells (positive control) no co-localization of Rab5a-GFP and transported Fl-LDL in VSMC could be found, supporting a mechanism independent of phagocytosis. Rescue of the VSMC from co-culture and subsequent analysis demonstrated an increase in phagocytotic activity compared to VSMC co-cultured in a trans-well with MP. Xenogenic cell composure (rat VSMC, human MP) and subsequent quantitative RT-PCR with rat specific primers demonstrated induction of genes typical for MP (CD68 and Mac2) and a concomitant downregulation of cholersterol sensitve genes (HMG-CoA reductase) in VSMC. These results demonstrate an active and phagocytosis independent exchange of LDL/cholesterol from MP into VSMC and imply that MP are capable of transforming a plaque stabilizing VSMC into a plaque destabilizing foam cell like cell.
Abstract 5149: Ambulatory Blood Pressure in a Large Cohort of Treated Hypertensive Subjects
Authors: Alejandro De La Sierra, Jose R Banegas, Julian Segura, Manuel Gorostidi, Juan J de la Cruz, Luis M Ruilope
Journal: Circulation (2009)

Aim: To examine the concordance of blood pressure control by means of both clinic (office) measurements and ambulatory blood pressure monitoring (ABPM), in a large cohort of treated hypertensive subjects from the Spanish Ambulatory Blood Pressure Monitoring registry Methods: A total number of 43 499 hypertensives under antihypertensive treatment were analyzed. Office BP control was defined if the patient had BP below 140/90 mmHg. Ambulatory BP control was considered by means of 3 different criteria: if daytime BP (based on patient’s reported activity) was below 135/85 mmHg. if 24-hour BP was below 130/80 mmHg, and if nighttime BP was below 120/70 mmHg. Clinical characteristics were compared between patients with daytime BP below or above 135/85 mmHg Results: Table 1 shows numbers and proportions of patient having control or lack of control by means of office and ABPM (the 3 criteria used). Concordant control of BP was present in 17.4%, 15.7%, and 12.9%, by the 3 different criteria. The main source of difference between office and ABPM was the proportion of patients with isolated office resistance, the proportion of which, using the 3 aforementioned criteria was 34.5%, 29.1%, and 26.8%, respectively. When compared to patients with normal ABPM values, the presence of elevated daytime BP (higher than 135/85 mmHg) was associated (p&lt;0.001 for all comparisons) with male gender (57.5% vs 47.7%), diabetes (25.1% vs 20.9%), smoking (17.5% vs 12.5%), left ventricular hypertrophy on EKG (11.1 vs 9.1), and chronic kidney disease (3.0% vs 2.0%). Conclusion: Blood pressure control in the treated hypertensive population by using ABPM is twice as observed by office measurements. The proportion of patients with isolated office resistance (white coat) is relatively large. Normal values of ABPM in treated patients are more frequent in women, nondiabetic, and nonsmokers subjects, as well as in those without organ damage. Blood Pressure Control by means of Office and ABPM measurements
Abstract 4857: Relationship Between Arterial Stiffness and Cardiac Structure and Function in Patients With Hypertension and Diastolic Dysfunction: The VALIDD Trial
Authors: Anil Verma, Akshay Desai, Chung-Lieh Hung, Rajesh Janardhanan, Gerard Aurigemma, James Thomas, Michael Zile, Scott D Solomon
Journal: Circulation (2009)

Background: Although both vascular and ventricular stiffness are increased in hypertension, the degree to which these abnormalities are related has not been well characterized Methods: Echocardiographic measures of LV structure and function were assessed in 384 patients enrolled in the VALsartan In Diastolic Dysfunction (VALIDD) trial with mild hypertension (mean blood pressure 144±16/86±10 and LV hypertrophy &lt; 4%), no heart failure and evidence of diastolic dysfunction, based on Doppler assessment of myocardial relaxation velocities (E′). Arterial compliance was calculated as stroke volume (SV)/pulse pressure (PP) with a lower ratio indicative of reduced compliance. Peak longitudinal systolic strain rate (SR) was measured in all 12 LV segments from 2 and 4 chamber views using speckle tracking. Results: Arterial compliance decreased with older age, female gender, and systolic pressure. In a multivariate model reduced arterial compliance was independently associated with lower E′ (r=0.22, p&lt;0.001) and longitudinal systolic SR (r=−0.18, p&lt;0.001) and with higher filling pressures (assessed either as E/E′ or as NTproBNP), increased end diastolic instantaneous operative LV stiffness (E/E′ ratio/LV EDV) and with increased LV mass and concentric remodeling [Table ]. Conclusion: Even amongst patients with mild degree of hypertension, arterial stiffness is related to abnormalities in LV structure, and diastolic and systolic function. These results suggest that both diastolic dysfunction and arterial stiffness are pathophysiologically linked to end-organ consequences of hypertension.