bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 213: Myofilament Ca2+ Sensitization and Site-specific Phosphorylation of Contractile Proteins Following Myocardial Infarction: A Novel Role for Mast Cells
Authors: Ngkelo Anta , Kirk Jonathan , Richart Adele , Bonnin Philippe , Vilar Jose , Heymes Christophe , Rodewald Hans-Reimer , Kass David , Silvestre Jean-Sebastien 
Published: July 2021

Inflammatory cells orchestrate post-ischemic cardiac remodeling after myocardial infarction (MI). Studies in Kit mutant mice suggest key roles for mast cells in post-ischemic tissue remodeling. However, Kit mutations affect multiple cell types of both immune and non-immune origin. The aim of this study was to address the impact of mast cells on cardiac function following MI, using selectively mast cell-deficient mice (Cpa3Cre/+ mice).
In response to myocardial infarction, mast cells progenitors’ numbers (Lin-CD45+CD34+FcγRII/IIIhighβ7+) increased in the white adipose tissue (day 3) and in the heart (day 5) and mature mast cells (CD117+FcεRI+Sca1+) peaked at day 7 in the cardiac tissue. To assess the functional effect of this mast cell infiltration in the heart, cardiac function 14 days following MI was assessed in wild-type (WT) and Cpa3Cre/+ mice. There was a significant decrease of the left ventricular shortening fraction in Cpa3Cre/+ compared to WT mice (17.27±1.9 % vs 28.15±1.7, p<0.01) that was not due to adverse cardiac remodeling; with no significant difference on levels of fibrosis, cardiomyocyte apoptosis, infarct size or neovascularization. By contrast, we observed a significant reduction in cardiomyocyte contractility (both cell shortening and ±dL/dt) in Cpa3Cre/+ mice compared to WT mice 14 days post MI. In addition, Ca2+ sensitivity (EC50) declined in Cpa3Cre/+ -derived skinned myocytes (p<0.01 vs WT) and correlated with increased PKA-dependent phosphorylation of both cardiac troponin (cTn)I (Ser22/23) and myosin-binding protein-C (MyBPC) (Ser273) (p<0.05).
This study identifies a novel function of mast cells on modulating cardiomyocyte contractility via alteration of PKA-regulated Ca2+ handling and myofilament protein phosphorylation. Identification of the mast cell-dependent signaling pathway that targets cardiac performance will provide a new platform of regulators with potential cardioprotective properties.
Abstract 268: Adiponectin Ameliorates Palmitate Acid Induced Endothelial Inflammation in Endothelial Cells
Authors: Chen Xiuping , Zhao Wenwen , Zhang Xuenong , Wu Chuanhong 
Published: July 2021

Endothelial dysfunction (ED) is considered an early event of cardiovascular diseases including hypertension, atherosclerosis and so on. Inflammation participates centrally in all stages of cardiovascular diseases and is considered as a hallmark of endothelial dysfunction. In this study, the effect of adiponectin (APN), an adipocytokine derived mainly from adipocytes, on palmitate acid (PA)-induced inflammation in endothelial cells. Human umbilical vein endothelial cells (HUVECs) were treated with PA with or without APN pretreatment. The mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and ICAM-1 were measured with RT-PCR. The protein expression of ICAM-1, NOX1, NOX2, NOX4, and phosphorylation of MAPKs (JNK, ERK, and p38MAPK), IKKβ, p65 NF-κB were determined by Western blotting. Intracellular reactive oxygen species (ROS) and nitric oxide (NO) formation were determined with DCFH2-DA and DAF-FM respectively. APN significantly ameliorated PA-induced mRNA expression of TNF-α, IL-6 and ICAM-1 and protein expression of ICAM-1, NOX2, and phosphorylation of IKKβ, p65 NF-κB, p38MAPK, without affecting NOX2 and phosphorylation of JNK and ERK. APN also partly reversed PA induced ROS formation and NO decrease. NAC, a ROS scavenger, showed similar activities. The p38MAK inhibitor, SB203580, also reversed PA induced protein expression of ICAM-1 and mRNA expression of TNF-α, IL-6 and ICAM-1. Taken together, these results showed that APN improved PA induced endothelial dysfunction by regulating ROS/p38MAK/NF-κB pathways.
Acknowledgement: This study was supported by the National Natural Science Foundation of China (No. 81160048) and the Science and Technology Development Fund of Macau Special Administrative Region (No. 021/2012/A1).
Abstract 29: PCSK9 Association With Lipoprotein(a)
Authors: Tavori Hagai , Giunzioni Ilaria , Yeang Calvin , Tsimikas Sotirios , Shapiro Michael D , Duell Barton P , Fazio Sergio 
Published: July 2021

Monoclonal antibodies (mAb) against PCSK9 lower plasma LDL-cholesterol levels by increasing the lifespan of LDL receptors (LDLR). Significant effects on lipoprotein(a) [Lp(a)] have also been observed, but the mechanism for this is neither known nor intuitive since Lp(a) is not cleared by LDLR. Our and other laboratories have shown that PCSK9 associates with LDL in plasma. Here, we aimed to study whether PCSK9 also associates with Lp(a) particles and whether this association depends on Lp(a) levels and/or apo(a) size. Using sandwich ELISA we determined that plasma PCSK9 is indeed associated with Lp(a) particles in patient with high Lp(a) levels (>30mg/dl). We then isolated LDL and Lp(a) fractions from plasma of 8 patients with high Lp(a) levels, ranging from 36 to 224 mg/dl, and determined PCSK9 and apoB levels as well as apo(a) isoforms. Our results show a 17.8 fold higher PCSK9/apoB ratio for Lp(a) compared with LDL (Fig. 1A), which suggests a preferential distribution of PCSK9 with Lp(a), at least in high Lp(a) individuals. Surprisingly, the preferential association of PCSK9 with Lp(a) was inversely correlated to Lp(a) levels (Fig. 1B) and independent of LDL levels. Since Lp(a) levels are inversely correlated with the size of apo(a), we set out to determine whether PCSK9 association with Lp(a) is related to the molecular weight of apo(a). Using plasma of patients with two distinct apo(a) isoforms, we show that PCSK9 associates exclusively with the higher molecular weight of apo(a) (Fig. 1C).
Our results suggest that Lp(a)-bound PCSK9 exists in plasma of patients with high Lp(a) and that this association depends on the size of apo(a). This provides a possible mechanism for the reduction in Lp(a) caused by PCSK9mAb, as immune complexes mAb-PCSK9-Lp(a) may be cleared via the mononuclear phagocyte system.
Abstract 380: Vascular Pcsk9: A Mediator for Atherogenesis Independent of LDL Receptor
Authors: Sun Hua , Tan Michael , Teng Ba-bie 
Published: July 2021

PCSK9 (Proprotein convertase subtilisin/kexin type 9) increases the LDL levels by binding to hepatocyte LDL receptors (LDLR) and subjects it to degradation. We show that PCSK9 regulates apolipoprotein B (apoB) production by inhibiting its degradation process via the autophagic pathway, irrespective of the presence of LDLR. In addition to the role of PCSK9 in promoting hyperlipidemia, we hypothesized that vascular-PCSK9 in endothelial cells (EC) plays a role in initiating atherogenesis, irrespective of the presence of LDL receptor.
Our laboratory has generated double knockout mice lacking both LDLR and Apobec1 (apoB mRNA editing enzyme), named LDb, Ldlr-/-Apobec1-/-. They have the lipoprotein phenotype mimics human with hyperlipidemia; elevated levels of VLDL and LDL with low levels of HDL. They develop atherosclerotic lesions spontaneously. To investigate the role of PCSK9 in atherogenesis, we deleted Pcsk9 gene from LDb mice to generate the triple knockout mice (named LTp, Ldlr-/-Apobec1-/-Pcsk9-/-). In comparison to LDb mice (n=14), the LTp mice (n=8) had significantly decreased levels of cholesterol (387±10 vs. 313±14 mg/dl; p<0.0008) and triglyceride (304±15 vs. 204±2.3 mg/dl; p<0.0002). However, despite their high cholesterol levels at over 300 mg/dl, the atherosclerotic lesions in LTp mice were significantly decreased in comparison to LDb mice (8.8%±3.5 vs. 24%±3.3, p=0.004, n=5 vs. 5). We hypothesized that vascular PCSK9 regulates the development of atherosclerosis. We incubated LDL containing PCSK9 (LDL/PCSK9) on primary aortic endothelial cells (EC) obtained from LDb or LTp to study the effects of LDL/PCSK9 on inflammation. We show that LDL/PCSK9 could not induce the expressions of Lox-1, TLR-2, or ICAM-1 in EC from LTp, resulting in absence responses on proinflammatory markers (CCL2 and CCL7) and autophagic molecules (p62 and TRAF6). In conclusion, our results suggest that vascular PCSK9 play an essential role in atherogenesis.
Abstract 39: Circulating MiRNA Signature of Pet-Positive Abdominal Aortic Aneurysms: New Potential Predictors of Rupture
Authors: Courtois Audrey , Nusgens Betty , Hustinx Roland , Defraigne Jean-Olivier , Colige Alain , Sakalihasan Natzi 
Published: July 2021

Prediction of abdominal aortic aneurysm (AAA) rupture by specific biomarkers is a challenging issue in the field of vascular diseases. Small non-coding RNAs, miRNAs, are potent post-transcriptional regulators of gene expression and were found to be present in blood and to represent valuable biomarkers for a variety of diseases, notably in cancer. Recently, we showed that a positive uptake of 18F-fluorodeoxyglucose (FDG) in the aneurysmal wall observed by positron emission tomography (PET) was correlated with a higher instability of the wall which could lead to its rupture. Identifying circulating miRNAs correlated with a positive PET could help discriminating patients at higher risk of rupture.
The expression level of 372 miRNAs was evaluated by using the miScript PCR system (Qiagen) in the plasma of 45 AAA patients among whom 24 had no FDG uptake (A0) and 21 displayed a positive PET (A+). In a first approach, 4 pools of plasma samples from the A0 and the A+ groups were analyzed. 14 miRNAs were found significantly modulated (8 downregulated and 6 upregulated, p<0.05) in A+ as compared to A0 patients. The modulation of expression of 8 of these miRNAs was validated by qRT-PCR on the individual samples. Among the decreased miRNA, miR-204-5p has been previously found to be downregulated in the aneurysmal wall compared to healthy aortas. These 8 miRNAs found modulated in blood were then analyzed in the media of A+ wall at the FDG uptake site and compared to a negative site of the aneurysm from the same patient. Two of these 8 miRNAs, miR-125b-5p and miR-204-5p, were significantly downregulated in the FDG uptake site in 6 patients.
In conclusion, 8 circulating miRNAs might represent a new signature of PET+ AAA, at high risk of rupture. Moreover, 2 of them are significantly downregulated in the metabolically active aneurysmal wall prone to rupture. It is noteworthy that a validated target of miR-125b-5p is MMP13, a collagenase that we previously showed to be largely increased in the positive FDG uptake site of adventitia and that could be potentially involved in the ultimate degradation of collagen leading to aneurysmal rupture.
Abstract 418: Microfibrillar-Associated Protein 4 Deficiency Reduces Size and Incidence Rate of Angiotensin II Induced Abdominal Aortic Aneurysms in Mice
Authors: Kirketerp-Møller Katrine L , Stubbe Jane , Schlosser Anders , Kejling Karin , Møller Jesper B , Marcussen Niels , Hansen Pernille B , Shi Guo-Ping , Holmskov Uffe , Sørensen Grith L 
Published: July 2021

Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix (ECM) protein primarily located in elastic arteries. It can bind elastin and collagen, and furthermore activate vascular cells through cellular integrin binding and modulate matrix metalloprotinase (MMP) activity. We hypothesized that lack of MFAP4 would decrease vascular inflammation and abdominal aortic aneurysm (AAA) formation.
AAA was induced in 9-11 week old mice using two experimental mouse models:

1) Male

Mfap4
-/-
/ApoE
-/-

double knock-out (dKO) and

ApoE
-/-

littermate control mice were feed western diet and subjected to continuously angiotensin II (AngII, 1000 ng/kg/min) infusion for 9-28 days via subcutaneous osmotic mini-pumps. Arterial blood pressure was measured in the femoral artery.

2) 1.5 U/mL elastase was infused into the infrarenal aorta in

Mfap4
-/-

and littermate

Mfap4
+/+

mice for 5 minutes. Aortic blood flow was restored and the mice recovered for 9-16 days.

Aortic diameter was measured in mice subjected to AngII or elastase infusion at day 28 and 16 respectively. MMP activity was detected by zymography.

No difference in AAA formation was observed between genotypes after elastase perfusion. In response to AngII infusion dKO mice showed a significantly decrease in AAA diameter and incidence rate compared to

ApoE
-/-

mice. AngII-induced increase in blood pressure was not dependent of MFAP4. However, there was decreased aortic arch atherosclerotic plaque formation, MMP2 and MMP9 activity in aortic tissue from dKO mice compared to

ApoE
-/-

mice. Furthermore there was a non-significant tendency of decreased elastin degradation score in the AngII infused dKO mice, however this was not observed in the elastase perfused mice. Activity of MMP12 and extent of infiltrating leukocytes in aneurysmal tissue from both models will be further investigated.

In conclusion we observed a decreased AAA formation and MMP activity in

Mfap4
-/-
/ApoE
-/-

mice which was not explained by variation in blood pressure or altered elastin degradation. The data suggest that MFAP4 induces MMP2-activity and thus the propensity for AAA formation.
Abstract 439: Biomechanical Stimulation Promotes Translocation of Nuclear Factor of Activated T-cells 5 Into The Nucleus of Vascular Smooth Muscle Cells
Authors: Hödebeck Maren , Hecker Markus , Korff Thomas 
Published: July 2021

Chronic alterations in the biomechanical stimulation of vascular smooth muscle cells (VSMC) as experienced during hypertension lead to changes in VSMC phenotype and function and further enable the structural remodeling of the vessel wall. In this context, we recently reported that an increase in wall stress or biomechanical stretch is sufficient to activate nuclear factor of activated T-cells 5 (NFAT5). This transcription factor promotes the expression of gene products such as tenascin-C and κ-actin, both involved in VSMC migration. Based on these findings, we hypothesized that biomechanical stretch elicits NFAT5 mRNA expression and induces biochemical modifications of NFAT5 on the post-translational level, a prerequisite for its entry into the nucleus and transcriptional activity. To scrutinize this hypothesis, human arterial VSMC were exposed to biomechanical stretch (13%, 0.5 Hz) and subjected to detailed mRNA expression analyses. While a ~3-fold reduction in NFAT5 splice variant 1 (isoform A) mRNA expression was observed in stretch-stimulated VSMC as compared to the static controls (n=3, p<0.05), splice variant 3 (isoform C) mRNA levels were induced ~1.8-fold (n=3, p<0.05). Overexpression of corresponding Flag-tagged NFAT5 proteins in VSMC and subsequent immunofluorescence as well as biochemical analyses revealed that isoform A was primarily located in the cytoplasm of static and stretch-stimulated VSMC while isoform C was preferentially localized in the nucleus under baseline conditions and further accumulated in the nucleus upon biomechanical stimulation (n=3, p<0.05). Nuclear translocation of isoform C was amplified for phosphorylation-deficient mutants generated by exchanging serine to alanine at position 1197 even under static culture conditions while a phosphomimetic mutation at this residue (serine to glutamate) inhibited NFAT5c nuclear translocation (n=3, p<0.05).
Collectively, our findings indicate that exposure of VSMC to biomechanical stretch triggers the expression of NFAT5 isoform C and controls its entry into the nucleus via phosphorylation at S-1197. Current investigations are focusing on the impact of NFAT5 on hypertensive remodeling utilizing inducible smooth muscle cell-specific NFAT5-deficient mice.
Abstract 717: An Association between Frontal Non-hemorrhagic Stroke and Atrial Fibrillation.
Authors: Sedhom Daniel , Yager Neil , Ashamalla Michael , Ghate Ketan , Pieper Justin , Nguyen Veronica , Shkolnik Boris , Torosoff Mikhail 
Published: July 2021

Background:
Atrial fibrillation is a known risk factor for thromboembolic events. We sought to investigate an association between arrhythmia and stroke location in patients with non-hemorrhagic stroke.

Materials and methods:
The study cohort included 514 consecutive patients with non-hemorrhagic stroke treated at a single academic center. Stroke location was classified as frontal, occipital, lacunar, brainstem, left or right temporal, left or right parietal, cerebellar and insular. ANOVA, chi-square and logistic regression analyses were used. The study was approved by the institutional IRB.

Results:
Frontal embolic stroke was noted more frequently in patients with atrial fibrillation (29% vs. 15% in normal sinus rhythm, NSR, p<0.0001). No other anatomic location of the stroke was associated with arrhythmia.

Frontal strokes were more likely in patients with history of coronary artery disease (23% vs. 12%, p<0.005). However, there was no association between frontal stroke location and gender, age, history of hypertension, diabetes, dyslipidemia, peripheral vascular disease, or chronic renal insufficiency.
In multivariate logistic regression analysis, atrial fibrillation (HR 2.3; 95% CI 1.2-4.5, p=0.018) and history of coronary artery disease (HR 2; 95%CI 1.2-3.4, p=0.012) remained important predictors of frontal strokes.

Discussion:
Non-hemorrhagic strokes are common in patients with atrial fibrillation. We found increased prevalence of frontal embolic strokes in atrial fibrillation, possible due to the dual blood supply the frontal cerebrum from both the middle and anterior cerebral arteries. This association is intriguing and requires further studies.
Abstract 665: Hypertension Is Associated With Phenotypic Changes Of Peripheral Blood Monocytes.
Authors: Guzik Tomasz J , Bzowska Malgorzata , Czesnikiewicz-Guzik Marta , Jasiewicz-Honkisz Barbara , Adamek-Guzik Teresa , Korbut Ryszard , Pryjma Juliusz 
Published: July 2021

While immunopathogenesis of atherosclerosis is well defined, immunological mechanisms of hypertension (HTN) and its link to atherosclerosis remain unclear. We hypothesized, that primary HTN is associated with a pro-inflammatory and pro-atherogenic phenotype of circulating monocytes, characterized by co-expression of the Fc-gamma receptor (CD16+) and LPS receptor (CD14+high).
Methods: 132 subjects (74M and 58F) with typical clinical risk factors of atherosclerosis were studied. HTN (85%) was diagnosed based on blood pressure monitoring and use of anti-HTN drugs. Monocyte characteristics in the peripheral blood were determined by flow cytometry and plasma cytokine levels by ELISA.

Results: CD16+CD14+ cells were more prevalent in subjects with HTN and were highest in subjects whose blood pressure was poorly controlled (Figure

). A significant correlation between blood pressure levels at the time of study (JNC7) and prevalence of CD14+CD16+ monocytes was found (Figure

). These relationships remained significant in multi-variate analysis (p = 0.01; type 3 sum of squares ANOVA) taking into account other major risk factors for atherosclerosis or treatments. Further analysis of subpopulations showed that levels of CD16 +CD14+ (high) monocytes, rather than CD16 + CD14(dim) revealed a strong relationship to hypertension. These monocytes showed significantly higher expression of activation markers HLA-DR and CD45RA and TNF-α production(p<0.05). These results provide a novel marker of inflammation in hypertension and may provide a link between hypertension and the development of atherosclerosis, which has been clinically well defined, but mechanistically unclear.
Abstract 724: Synectin is Required for Normal PDGF Secretion and Smooth Muscle Cell Basic Science Recruitment
Authors: Paye Julie M , Chittenden Thomas W , Phng Li-Kun , Gerhardt Holger , Simons Michael 
Published: July 2021

Background: Synectin, a ubiquitously expressed scaffold and PDZ protein, has been shown to be a key regulator in the formation of arterial vasculature. Primary arterial endothelial cells isolated from synectin−/− mice exhibited defects in PDGF signaling that were not present in arterial synectin+/+ or either venous synectin+/+ or synectin−/− endothelial cells.
Methods: To address the role of synectin in mural cell recruitment, retinas from synectin−/− (KO) and synectin+/+ (WT) mice were stained for isolectin and alpha-smooth muscle actin. To determine the mechanisms responsible for defective smooth muscle cells recruitment, primary arterial and venous endothelial (EC) and smooth muscle (SMC) cells were isolated from synectin+/+ and synectin−/− mice.
Results: Examination of the retinal vasculature in synectin−/− mice demonstrated poor smooth muscle cell coverage of the forming arterial tree with a number of SMC cells sitting some distance away from the vessels, a defect reminiscent of retinal abnormalities observed in PDGF-B−/− mice. Western blot analysis of lysates from primary KO SMC demonstrated levels of PDGFR-β analogous to WT, although expression of PDGF-B was markedly reduced in lysates from arterial, but not venous, primary KO endothelial cells. Transduction of KO EC with an adenoviral synectin construct was sufficient to restore PDGF-B protein levels. Further, qPCR was used to determine whether defects in PDGF-B protein production were at the transcription or translation level. Interestingly, there was only a minor decrease in the amount of PDGF-B mRNA in KO compared to WT EC, suggesting that synectin deficiency has selectively affected post-transcriptional regulation of PDGF-B expression. Migration of WT and KO SMC in response to PDGF-B or conditioned media from WT and KO endothelial cells was also assessed to determine the cell type specificity of PDGF defects in KO mice.
Conclusions: Synectin is required for post-transcriptional regulation of PDGF-B in endothelial cells. Deficits in PDGF-B secretion by synectin−/− endothelial cells result in inadequate smooth muscle recruitment and coverage of arterial vessels.
Abstract 879: The Chemokine CXCL10 Is Involved In The Development Of Atherosclerotic Plaque Vulnerability
Authors: Segers Dolf , de Crom Rini , Leenen Pieter , Pasterkamp Gerard , Krams Rob 
Published: July 2021

Introduction: Atherosclerosis is an inflammatory disease in which monocyte/macrophages and Th1 cells are crucial cell types. The CXC-chemokine CXCL10 might play a pivotal role in its pathogenesis as it mediates chemoattraction of these cells. We previously found that high CXCL10 levels in human carotid plaques are associated with a vulnerable phenotype. Moreover, we identified CXCL10 as a possible biomarker for vulnerability in a mouse model for vulnerable plaque. The aim of the current study was to evaluate if CXCL10 has a critical role in the development of plaque vulnerability.
Methods: Atherosclerosis-susceptible female ApoE -/-mice on high fat, high cholesterol diet were instrumented with a perivascular shear stress-altering plastic cylinder to induce vulnerable plaque. In the first three weeks following surgery, mice were injected 3 times/week with a bioactivity-neutralizing CXCL10 antibody. After 9 weeks, plaques were harvested and sections were evaluated for macrophages (CD68), immune activation (MHC class II), smooth muscle cells (a-actin), lipids (Oil Red O) and collagen (picrosirius red).
Results: Lesion sizes were equal in both the intervention group and the control group. Also lipid accumulation was comparable in both groups. Despite unaffected macrophage content (30.1 vs 28.7% p = 0.73), we did find a 2-fold reduction of MHC class-II expression (4.9 vs 14.5% p = 0.011) in the antibody-treated group. This decline in activation of the immune system coincided with an increase in the presence of smooth muscle cells (12.6 vs 4.2% p = 0.034) and an increase in collagen content (9.7 vs 21.8% p = 0.014).
Conclusion: This study confirms a pivotal role of CXCL10 in the development of vulnerable plaque. Inhibiting CXCL10 resulted in an increase of plaque stability by decreasing immune activation and increasing smooth muscle cell and collagen content. Accordingly, CXCL10 is a potential marker for both diagnostic and therapeutic intervention.