tbuckley/cabot-search huggingface dataset:
Abstract 13228: SUMO2 Induces Cardiac Hypertrophy <i>in Vivo</i> and <i>in Vitro</i> , Independent of Sumoylation
Authors: Alexander Bernt, Ashraf Y Rangrez, Matthias Eden, Claudia Rohr, Sylvia Katz, Andreas Jungmann, Tatjana Williams, Oliver Ritter, Oliver J Müller, Hugo A Katus, Derk Frank, Norbert Frey
Journal: Circulation (2016)

Introduction: The calcineurin (Cn)-NFAT signaling axis is a pivotal pathway in cardiac physiology and pathophysiology including remodeling and pathological hypertrophy. Methods and results: We have previously shown that SUMO2 (S2) is a strong activator of Cn-NFAT signaling and, furthermore, is a direct interaction partner of Cn. S2 is sufficient and necessary to induce cardiomyocyte hypertrophy in NRVCMs. Interestingly, a sumoylation-deficient mutant of S2, S2ΔGG, yielded similar results in every parameter investigated. Overexpression of S2 or S2ΔGG enhances nuclear CnA localization as evidenced by subcellular fractionation as well as immunofluorescence experiments. The direct interaction of S2 and CnA is further supported by proximity-ligation-experiments in NRVCM. Additionally, knockdown of Ubc9, the sole E2-enzyme in the sumoylation cascade, had no significant influence on S2‘s effects, further supporting a sumoylation-independent mechanism. Knockdown of S2 revealed its necessity for agonist induced hypertrophy as shown by an abrogation of phenylephrine induced hypertrophy (median cell size: miRNeg+PE=512 μm 2 , miRS2+PE=519 μm 2 , n&gt;3000 cells) and diminished expression of fetal genes and Rcan-1.4 (miRNeg+PE vs. miR-S2+PE: Nppa : -41%, Nppb : -57%, Rcan1.4 : -80%; p&lt;0.001, n=6). On the basis of these in vitro findings, we designed an AAV9 gene transfer approach for S2 and S2ΔGG in mice, as a proof-of-principle for the in vivo relevance of this mechanism. In line with the proposed mechanism, both S2 constructs induced cardiac hypertrophy with elevated heart weight to body weight ratio (+25%, p&lt;0.05; n=6 mice) and increased lung weight to body weight ratio (+20%, p&lt;0.05) as a sign of heart failure. Consistent with pathological hypertrophy, fractional shortening (FS) and ejection fraction (EF) were reduced (FS, Ctrl: 25%, S2: 19%, S2ΔGG: 20%; p&lt;0.05; EF: Ctrl: 37%, S2: 26%, S2ΔGG: 30%; p&lt;0.01). Furthermore these animals showed elevated Nppb (S2: 2.7-fold, S2ΔGG: 2.4-fold; p&lt;0.01) and Rcan1.4 levels (S2: 4.5-fold, S2ΔGG: 5.5-fold; p&lt;0.01). Conclusions: We propose a mechanism where S2 causes cardiac hypertrophy, independent of sumoylation, by a direct interaction with calcineurin A, facilitating its translocation to the nucleus.
Abstract 13229: Varying ABCG1 Expression is Associated With Macrophage Apoptosis&amp;Phagocytosis
Authors: Si-Qi Shen, Fang Liu, Wei Wang, Lian-Feng Chen, Xiao-Wei Yan
Journal: Circulation (2016)

Introduction: ATP-binding cassette transporter G1(ABCG1)is a transmembrane protein mediated efflux of cellular cholesterol to HDL, which plays a vital part in macrophage lipid homeostasis, but the role of ABCG1 in atherosclerosis still remains controversial. Our previous study demonstrated that human ABCG1 -367 G&gt;A polymorphism in promoter region, which leads to lower ABCG1 protein expression, was associated with a reduced risk of CAD. However, the mechanism behind is not fully understood. Hypothesis: Oxysterols, the oxidized derivatives of cholesterol, whose efflux are mediated by ABCG1, exert cytotoxic effect on macrophage and accelerate cell apoptosis. Low ABCG1 expression induces excess oxysterols accumulation in macrophage, which augments the inflammatory response and accelerates apoptosis. Since defective apoptotic macrophage clearance in late lesions promotes atherosclerosis progression, we hypothesize that macrophage with lower ABCG1 expression may remove apoptotic cells more efficiently, thereby generating an antiatherogenic effect. Methods: To investigate the effect of ABCG1 expression on macrophage, we established ABCG1 knockdown cell line by means of lentivirus mediated shRNA. Apoptosis was determined by flow cytometry (FCM). Fluorescence labeled apoptotic model was generated and macrophage phagocytosis was evaluated. The inflammatory factors level and phagocytosis associated gene expression were measured by ELISA and realtime PCR. Results: Compared with control group, macrophage with lower ABCG1 expression had a higher secretion level of Inflammatory factors, such as TNF-α and IL-1β, showing an increased expression of classic inflammatory M1 phenotype markers,such as CD86 and TGF-β, and a down-regulation of CD163,Arg and IL-6 expression, which are markers of anti-inflammatory M2 phenotype macrophage. The apoptosis was significantly accelerated and the phagocytic clearance was enhanced after ABCG1 expression decreased, which means apoptotic cells could be removed more quickly. Both CD36 and Mertk showed a higher mRNA level in ABCG1 knockdown group. Conclusions: Decreased expression of macrophage ABCG1 may exert antiatherogenic function through accelerating apoptosis and enhancing phagocytosis.
Abstract 14123: Circulating miRNAs as Biomarkers of Afterload, Acute Vascular Reactivity, and Ventricular-Vascular Coupling in Pediatric Idiopathic Pulmonary Arterial Hypertension: Initial Clinical Studies
Authors: Vitaly O Kheyfets, Uyen Truong, Jamie Dunning, Kendall Hunter, Carmen C Sucharov, Dunbar Ivy, Shelley Miyamoto, Robin Shandas
Journal: Circulation (2015)

Introduction: Although it is known that structural remodeling of the pulmonary arteries (PA) leads to increases in right ventricular (RV) afterload in pediatric idiopathic pulmonary arterial hypertension (iPAH), evaluating such changes early in the process continues to be challenging. Since biological markers such as microRNAs may manifest earlier than functional markers, and since such markers may be detected using simple blood draws, identifying correlations between microRNAs and RV or pulmonary vascular functional parameters would be particularly useful in tracking this disease. Methods: Blood was collected for 14 pediatric patients with iPAH while undergoing right heart catheterization (RHC). Taqman Low Density Arrays (TLDA) was used to quantify miRNA expression in each patient. RHC data was used to compute pulmonary vascular impedance, ventricular-vascular coupling (VVC), and other hemodynamic markers. VVC was computed from the pressure tracing using the single beat pressure method (Vanderpool RR, et al. Heart 2015;101:37–43). Results: miR-21, which frequently appears in the PAH literature, was well correlated with pulmonary vascular resistance index (PVRi) (r = 0.81, P &lt; 0.001, see Fig. 1a). Fig. 1b shows that the ratio of miR-150/571 is an excellent predictor of VVC (r = 0.91, P &lt; 0.05). Random Forest statistical machine learning identified miR-683 as a classifier of acute vascular reactivity, confirmed with receiver operating curves (AUC = 0.88, see Fig. 1c) Conclusion: Over a dozen circulating miRNAs were identified as potential biomarkers for pediatric iPAH from the aforementioned arrays, with several having strong correlations to afterload and acute vascular reactivity. The ratio of miR-150 (recognized as biomarker of PAH) and miR-571 (recognized as biomarker of heart failure) appears particularly promising as a predictor of ventricular-vascular decoupling.
Abstract 14133: Angiotensin II-induced Vascular Fibrosis was Prevented by Caveolin-1 Deficient Mice
Authors: Tatsuo Kawai, Steven J Forrester, Katherine J Elliot, Satoru Eguchi, Victor Rizzo
Journal: Circulation (2015)

Introduction: We have recently reported that caveolin-1 (Cav1) enriched membrane microdomains in vascular smooth muscle cells (VSMC) mediates a metalloprotease ADAM17-dependent EGF receptor (EGFR) transactivation, which is linked to vascular remodeling induced by AngII. Hypothesis: We have tested our hypothesis that Cav1, a major structural protein of caveolae, plays a critical role in AngII-mediated vascular remodeling via regulation of ADAM17 and EGFR. Methods: In vivo: 8 week old male Cav1-/- and control Cav+/+ wild-type mice (WT) were infused with AngII (1 μg/kg/min) for 2 weeks to induce vascular remodeling and hypertension. In vitro: Rat aortic VSMCs were cultured and stimulated with 100 nM AngII. Results: Upon AngII infusion, histological assessments demonstrated medial hypertrophy and perivascular fibrosis of coronary and renal arteries in WT mice compared to sham-operated mice. The AngII-infused WT mice also showed a phenotype of cardiac hypertrophy with increased HW/BW ratio (mg/g: 8.0±0.6 vs 5.7±0.7 p&lt;0.01) compared with sham-operated WT control. In contrast, vascular remodeling but not cardiac hypertrophy were attenuated in Cav1-/- mice with AngII infusion; HW/BW ratio (8.6±0.5 vs 6.4±0.2 p&lt;0.05) compared to sham-operated mice. However, AngII induced similar levels of hypertension in both WT and Cav1-/- mice as assessed by telemetry (MAP mmHg: 142±9 vs 154±20). AngII infusion in WT mice enhanced ADAM17 and phospho-Tyr EGFR staining in heart and kidney vasculature, whereas AngII-infused Cav1-/- mice showed diminished ADAM17 and phospho-Tyr EGFR staining within the vasculature. In addition, IHC analyses revealed reduced vascular ER stress in heart and kidney samples of AngII-infused Cav1-/- mice compared to WT mice. In cultured rat VSMC, Cav1 silencing attenuated induction and activation of ADAM17 by AngII. Conclusions: These data suggest that Cav1, and presumably caveolae microdomains, plays a critical role in vascular fibrosis via vascular induction of ADAM17 and activation of EGFR independent of blood pressure or cardiac hypertrophy regulation.
Abstract 18: Differential Effect of Analyze Early versus Analyze Late prior to Initial Rhythm Analysis in Out-of-Hospital Cardiac Arrest: the Role of EMS Agency
Authors: Thomas D Rea, David Prince, Laurie Morrison, Clifton Callaway, Tom Aufderheide, Mohamud Daya, Ian Stiell, James Christenson, Judy Powell, Craig Warden, Lois van Ottingham, Peter Kudenchuk, Myron Weisfeldt
Journal: Circulation (2013)

Background: An effective resuscitation strategy in one community may not be effective in another community. We hypothesized that a strategy that prioritized initial Emergency Medical Services (EMS) rhythm analysis (Analyze Early) would provide a survival advantage among EMS systems with lower baseline ventricular fibrillation (VF) survival, while one prioritizing initial EMS CPR (Analyze Late) would provide a survival advantage among systems with higher baseline VF survival. Methods: We conducted an ancillary study of Analyze Early versus Analyze Late randomized trial of the Resuscitation Outcomes Consortium. Subjects were stratified according to pretrial EMS agency VF survival and their randomization arm. The primary outcome was survival to hospital discharge with favorable functional status. We used a binomial family mixed-effects model to determine whether outcomes from the trial intervention differed according to pretrial EMS agency VF survival. Results: Characteristics were similar among patients randomized to Analyze Early (n=4964) versus Analyze Late (n=4426). For EMS agencies with pretrial VF survival ≤20%, Analyze Early compared to Analyze Late was associated with a higher likelihood of favorable functional survival (5.5% versus 3.8%, OR=1.50 [1.11,2.0]). Conversely, among agencies with pretrial VF survival &gt; 20%, Analyze Early compared to Analyze Late was associated with lower likelihood of favorable functional survival (6.1% versus 7.5%, OR=0.82 [0.66,1.02]). In the multivariable model, for every 10% improvement in pretrial VF survival, Analyze Late versus Analyze Early was associated with a 34% increase in the odds of favorable functional survival (OR=1.34 [1.07-1.66]). Conclusion: In this ancillary investigation of a clinical trial evaluating initial EMS CPR strategy, we observed a robust interaction indicating the Analyze Early strategy was associated with greater survival among EMS agencies with lower pretrial VF survival while the Analyze Late strategy was associated with greater survival among EMS agencies with a higher pretrial VF survival. The findings support distinct EMS CPR strategies based on a system’s baseline VF survival in order to achieve optimal outcomes following out-of-hospital cardiac arrest.
Abstract 18991: A Mir-208-mef2 Axis Drives the Decompensation of Right Ventricular Function in Pulmonary Hypertension
Authors: Roxane Paulin, Gopinath Sutendra, Vikram Gurtu, Peter Dromparis, Evangelos D Michelakis
Journal: Circulation (2013)

Right Ventricular Failure (RVF) is the major cause of morbidity and mortality in PHT but remains understudied compared to left ventricular failure. The transition from a compensated to decompensated RV occurs much earlier in the RV for unknown reasons. RV and LV have different embryology; the Islet1/Mef2/Hand2 axis is specific for RV formation. Mef2 regulates metabolic, contractile and angiogenic genes critical for RV adaptation to pressure overload. MicroRNAs (miRNAs) have emerged as important determinants of LV development and disease, but little is known about RV miRNAs. We hypothesized that a miRNA-Mef2 axis is important in RV decompensation. We modeled RVF in the rat monocrotaline (MCT) PAH model in a clinical manner, establishing 3 sequential stages of RV response to PAH (n=6/group): a) normal RV at baseline (NRV, RVSP=38±2mmHg, CO=102±2ml/min and RV/LV+Septum=22±1); b) compensated RV (CRV) 3-4weeks post-MCT when mortality is minimal and cardiac output is stable (RVSP=66±8 mmHg, CO=80±13ml/min, RV/LV+Septum=48±3); c) decompensated RV (DRV) 4-6weeks post-MCT when contractility and cardiac output declines while RV size, ascites and mortality increase rapidly (RVSP=52±2mmHg, CO=67±10ml/min, RV/LV+Septum=58±2). Using unbiased miRNA arrays (n=9), we found that the levels of the cardiac-specific miRNA miR-208 progressively decreased in CRV and DRV, correlating with RV size increase (r=-0.68, n=20, p&lt;0.001); whereas its expression is known to remain stable in models of LV hypertrophy. The level of the miR-208 target, MED13, increased in DRV. MED13, a subunit of the complex mediator of transcription, activates the repressor NCoR1, which deacetylates Mef2 family members, decreasing their transcriptional activity. NCoR1 expression was increased in DRV, while Mef2 expression was decreased. We infected adult cardiomyocytes isolated from CRV free walls with an adenovirus expressing an anti-miR-208. This was associated with increased MED13 and NCoR1 levels, and decreased Mef2 expression, mimicking the transition to DRV in vivo. We identified an RV-specific miR-208-Mef2 axis characterizing the transition from CRV to DRV, which may lead to the discovery of much-needed biomarkers and treatments of RVF, for which there are currently no treatments.
Abstract 13235: Enhanced Receptor-independent Nucleoside Diphosphate Kinase Mediated G <sub>s</sub> Protein Signaling Contributes to Arrhythmogenic Calcium Mishandling in Atrial Fibrillation
Authors: Marina Schaefer, Issam Abu-Taha, Patrice Naud, Xiao Yan Qi, Vanessa Gundlach, Markus Kamler, Thomas Wieland, Stanley Nattel, Dobromir Dobrev
Journal: Circulation (2016)

Background: Enhanced G-protein related cyclic AMP (cAMP) signaling and abnormal Ca 2+ handling due to dysfunctional ryanodine receptor type-2 (RyR2) are implicated in atrial fibrillation (AF). Nucleoside diphosphate kinase (NDPK) forms complexes with G s proteins, increasing cAMP signaling via receptor-independent G protein activation. Here, we studied the possible proarrhythmic role of NDPKs in clinical (chronic AF, cAF) and experimental AF. Methods: NDPK and G protein expression were assessed by immunoblotting in atria from sinus rhythm (Ctl) and cAF patients; dogs undergoing AF-mimicking tachycardia remodeling (ATR, 400 bpm, 7 days) or AF-promoting chronic atrial ischemia; and canine atrial cardiomyocytes (CMs) paced in vitro for 24-48 hrs at 1 (P1) or 3 Hz (P3). cAMP was measured by immunoassay. Immunostaining was used for protein visualization. Spontaneous sarcoplasmic reticulum (SR) Ca 2+ release events (SCaEs) in CMs overexpressing NDPKs or EGFP-control (adenoviral gene-transfer) were recorded with epifluorescence (Indo-1). Results: NDPK-B, NDPK-C, Gα s and Gβ 1 were upregulated in cAF patient atria (Fig A). ATR and chronic atrial ischemia increased NDPK-B expression in canine atria (Fig B). In vitro tachypacing reproduced AF effects on NDPK/Gα s in CMs (Fig C). Accordingly, cAMP levels were higher in cAF patients and P3-paced CMs (Fig D-E). Adenoviral NDPK-B and NDPK-C overexpression increased cAMP levels (Fig F). NDPK-B, NDPK-C and Gα s co-localized at the plasma membrane when upregulated by tachypacing canine CMs. SCaEs, a proarrhythmic consequence of diastolic SR Ca 2+ leak, were enhanced in NDPK-B or NDPK-C overexpressing CMs, and the latency from last regular SR Ca 2+ release was reduced (Fig G). Conclusions: Receptor-independent NDPK-mediated G s -protein/cAMP signaling is upregulated in clinical and experimental AF, causes arrhythmogenic SCaEs, and is likely a novel contributor to ectopy-inducing atrial triggered activity due to SR Ca 2+ leak.
AttSiOff: a self-attention-based approach on siRNA design with inhibition and off-target effect prediction
Authors: Bin Liu, Ye Yuan, Xiaoyong Pan, Hong-Bin Shen, Cheng Jin
Journal: Med-X (2024)

Abstract Small interfering RNA (siRNA) is often used for function study and expression regulation of specific genes, as well as the development of small molecule drugs. Selecting siRNAs with high inhibition and low off-target effects from massive candidates is always a great challenge. Increasing experimentally-validated samples can prompt the development of machine-learning-based algorithms, including Support Vector Machine (SVM), Convolutional Neural Network (CNN), and Graph Neural Network (GNN). However, these methods still suffer from limited accuracy and poor generalization in designing potent and specific siRNAs. In this study, we propose a novel approach for siRNA inhibition and off-target effect prediction, named AttSiOff. It combines a self-attention-based siRNA inhibition predictor with an mRNA searching package and an off-target filter. The predictor gives the inhibition score via analyzing the embedding of siRNA and local mRNA sequences, generated from the pre-trained RNA-FM model, as well as other meaningful prior-knowledge-based features. Self-attention mechanism can detect potentially decisive features, which may determine the inhibition of siRNA. It captures global and local dependencies more efficiently than normal convolutions. The tenfold cross-validation results indicate that our model outperforms all existing methods, achieving PCC of 0.81, SPCC of 0.84, and AUC of 0.886. It also reaches better performance of generalization and robustness on cross-dataset validation. In addition, the mRNA searching package could find all mature mRNAs for a given gene name from the GENOMES database, and the off-target filter can calculate the amount of unwanted off-target binding sites, which affects the specificity of siRNA. Experiments on five mature siRNA drugs, as well as a new target gene (AGT), show that AttSioff has excellent convenience and operability in practical applications. Graphical Abstract
Abstract 14156: Airway Gene Delivery of Serca2a Ameliorates Chronic Pulmonary Hypertension in a Large Animal Preclinical Model
Authors: Jaume Aguero, Kiyotake Ishikawa, Lahouaria Hadri, Carlos G Santos-Gallego, Kenneth M Fish, Nadjib Hammoudi, Borja Ibanez, Ana Garcia-Alvarez, Krisztina Zsebo, Maria Plataki, Valentin Fuster, Jane A Leopold, Roger J Hajjar
Journal: Circulation (2015)

Downregulation of sarcoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) in the pulmonary vasculature leads to perturbations in Ca2+ homeostasis, endothelial dysfunction, and transition of pulmonary artery smooth muscle cells from a contractile to a proliferative phenotype. To assess the feasibility and benefits of sustained pulmonary vascular SERCA2a gene transfer, we created a model of chronic post-capillary PH in Yorkshire swine by partial pulmonary vein banding. Development of chronic PH was hemodynamically confirmed, and animals were randomized to intratracheal administration of adeno-associated virus type 1 (AAV1) carrying the human SERCA2a gene (n=10, AAV1.SERCA2a group) or Saline (n=10). Transduction efficacy after intratracheal delivery of AAV1 was confirmed by β-galactosidase detection in the distal pulmonary vasculature and significant overexpression of SERCA2a protein at the distal airway and small pulmonary arteries. Two months after gene delivery, disease progression was prevented in AAV1.SERCA2a treated animals as assessed by mean pulmonary pressure (29[5] vs 54[20] mmHg, p=0.027, Figure) and pulmonary vascular resistance index (3.2[2.2] vs 10.3[7.1] Wood units*m2, p=0.020) along with decreased small vessel remodeling in the AAV1.SERCA2a group (p&lt;0.05). RV ejection fraction (61[7] vs 50[7] % units, p=0.014) was preserved and improvement of RV end-diastolic pressure-volume relationship (0.12[0.08] vs 0.28[0.07] mmHg/ml, p=0.08) in AAV1.SERCA2a treated pigs versus Saline. In conclusion, airway-based delivery of AAV vectors to the pulmonary arteries is feasible, efficient, and safe in a clinically relevant chronic PH model. Selective vascular SERCA2a overexpression results in beneficial effects on pulmonary hemodynamics and RV performance, and may offer therapeutic benefit by modifying fundamental pathophysiology in pulmonary vascular diseases.
Abstract 14205: A Role of Inositol 1,4,5-trisphosphate Receptors to Inhibit the Progression of Pulmonary Arterial Hypertension
Authors: Akimichi Shibata, Keiko Uchida, Reina Ishizaki, Takatoshi Tsuchihashi, Jun Maeda, Katsuhiko Mikoshiba, Hiroyuki Yamagishi
Journal: Circulation (2015)

Backgroud: Inositol 1,4,5-trisphosphate receptor (IP3R) is an intracellular Ca2+ release channel in response to extracellular stimulation. There are three subtypes of IP3R (IP3R1, 2 and 3) and IP3R2 may be predominantly expressed in the pulmonary arterial smooth muscle cells (PASMCs). Objectives: To elucidate the role of IP3R2 in the progression of pulmonary arterial hypertension (PAH). Methods: The detailed expression pattern of IP3R2 in pulmonary vasculature during development and adulthood was investigated in lung sections of transgenic mice in which a LacZ reporter gene was knocked into the IP3R2 locus. In order to elucidate whether IP3R2 play a role in progression of PAH, we utilized chronic hypoxia (10% O2 for 6 weeks) -induced PAH mouse models. The severity of PAH was evaluated by transthoracic echocardiography, the weight of right ventricle, and the thickness of tunica media of pulmonary arteries, and compared between wild type (WT) and IP3R2 knock out (KO) mice. Proliferation and apoptosis in PASMCs were also assessed in both mice by immuno-staining with anti-phospho-histone H3 (PHH3) antibody and TUNEL assay, respectively. Further, in vitro, capacitative Ca2+ entry was assessed by Ca2+ imaging in primarily cultured PASMCs from WT and IP3R2 KO lungs by loading with fluorescent Ca2+ probe (Fluo-4AM). Results: Strong expression of the IP3R2 was detected in pulmonary arteries, predominantly in medial wall, from embryonic periods to the adulthood. IP3R2 KO mice showed higher RV pressure than those in WT mice by echocardiography. RV hypertrophy and medial wall thickness of PASMCs were more severely progressed in KO. There was no significant increase of PHH3 positive cells, while there was significant decrease of TUNEL positive cells in KO PASMCs compared with WT, suggesting that apoptosis was inhibited in KO PASMCs. Ca2+ imaging revealed that store-operated Ca2+ entry (SOCE) was enhanced in KO compared with WT. Taken together, loss of IP3R2 function leads to the acceleration of the progression of chronic hypoxia-induced PAH, with depressed apoptosis and enhanced SOCE in PASMCs. Conclusions: Although IP3R2 functions in increase of cytosolic Ca2+, it may play an inhibitory role in pathophysiology of PAH by influencing to the apoptosis and SOCE in PASMCs.