bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperlipidemia interferes with the behavior of variant NKT cells
Authors: Shukla P , Chakrabarti R 
Published: October 2024

Abstract

Background
NKT cells significantly influence atherosclerosis development. However, inconsistent findings on the function of the NKT cells and the invariant subset in atherosclerosis remains a challenge. Moreover, there is no clarity on the role and phenotype of the variant (vNKT) subset in atherosclerosis.

Purpose
To understand the role of the vNKT subsets in HFD-induced atherosclerosis.

Methods
We extracted the data for meta-analysis to understand the role of the whole NKT and iNKT cells in atherosclerosis. PRISMA guidelines were followed for the meta-analysis. In addition, C57BL/6 mice (WT) were fed with HFD for 20 weeks from 6-8 weeks of age. vNKTs were identified as CD3+NK1.1+CD1d-tetramer- within the CD3+NK1.1+ NKT cell population in both liver and spleen by flow cytometry. Intracellular cyotkines staining was performed. Statistical differences inthe means of two groups are calculated by two-tailed Student’s t-test with nonparametric Mann-Whitney tests. P-value&lt;0.05 was considered significant. All data represented as mean±SEM.

Results
The NKT cell numbers increased significantly in the spleen, lymph nodes, blood, and liver in the HFD-fed mice fed from 1.5 to 24 weeks in Apoe-/-, Ldlr-/- in comparison to wild-type mice (SMD, 2.51 [95% CI, 1.42, 3.61]). Contrary to this, the iNKT cell numbers and the iNKT TCR gene expression levels, decreased significantly in the HFD-fed mice (SMD, -2.04 [95% CI, -3.34, -0.75]). The reduction in iNKT cell numbers is also supported by the clinical data from the AMI patients when compared to healthy controls [SMD = -1.81, 95% CI = -2.89, -0.74] (Figure 1). In HFD-fed C57BL/6 hyperlipidemic mice, significantly increased levels of total cholesterol (HFD vs Chow; 226.5±29.66 vs 118.5±10.56 mg/dL, n=4) and LDLc (44.56±11.96 vs 16.69±1.13 mg%, n=4) was observed. The number of vNKTs in the liver was significantly increased by 46% (HFD vs Chow 28.35±2.28 vs 19.41±1.36, n=6-7) (Figure 2A). However, the CD8+ vNKTs were significantly decreased by 68.6% in the liver (4.72±0.99 vs 15.06±0.96) and the CD4+ vNKTs decreased more than two times in the HFD-fed WT liver (7.39±0.76 vs 18.28±0.36) (Figure 2B). Also, the intracellular IFN-γ+ vNKT cells doubled in their numbers in the HFD-fed spleen (14.31±1.39 vs 6.367±0.87) compared to the chow-fed mice (Figure 2C).

Conclusion(s)
Meta-analysis revealed dual nature of the NKT cells and its invariant subsets in atherosclerosis, since the whole NKTs increase whereas the iNKTs decrease in number. The vNKT subset actively participates in immune modulation in the HFD-induced hyperlipidemia by increasing their number, as well as by differentially regulating CD8 and CD4 co-receptors between chow and HFD. HFD induced a pro-inflammatory nature in the splenic vNKTs but not in liver vNKTs, that in turn may aggravate other immune cells. This data confirms the dual nature of the NKT subsets and reveals a crucial systemic involvement of vNKT cells in the progression of dyslipidemia.
Polyphenol-treatment without preceding glutaraldehyde fixation: a potential paradigm change for bioprosthetic heart valves
Authors: Melica B , Colli A , Zilla P , George I 
Published: October 2024

Abstract

Background
Glutaraldehyde (GA) is the common fixative agent for bioprosthetic heart valves (BHVs). However, its chemical instability can expose calcium binding sites and, at commercially used concentrations, GA does not ensure effective immunological tolerance, triggering an immune response correlated to degeneration. Recently, polyphenols (PPs) achieved an almost complete xenoantigens inactivation in GA-fixed BHVs ensuring chemical stability of the treated tissue while improving mechanical characteristics and adding anti-infective and anti-thrombotic properties [1-4].

Purpose
A new PP-based treatment has been introduced as a potential GA substitute in BHV manufacturing. The unique chemical properties of PPs permit them to interact with the tissue through stable chemical bonds without depolymerization over time, achieving several improvements that promise to extend the long-term durability of BHVs (Fig.1).

Methods
The study compared the effects of two cross-linking methods on bovine pericardial tissue: (1) traditional fixation in GA, and (2) treatment with PPs without GA. The type of chemical interaction between PPs and tissue was evaluated through nuclear magnetic resonance. The xenoantigens inactivation was quantified in-vitro by ELISA test and in-vivo in a humanized mouse animal model. Biomechanical properties were assessed through uniaxial stress-strain tests and cross-link density through the shrinkage temperature test. The protective effect against bacterial adhesion was evaluated against a strain of S aureus, while the inhibition of thrombosis was evaluated in-vivo in a pig animal model and in-vitro in a blood-loop using bovine blood with radio-labeled platelets.

Results
PPs effectuated multiple chemical bonds with and within the pericardium including cross-links based on covalent and hydrogen bonds, stacking, and electrostatic interactions. The inactivation of over 90% of surface-xenoantigens of the treated tissue allowed for superior biocompatibility (compared to &lt;50% by commercial GA concentrations). The increase in elongation exhibited by PP-treated tissue confirmed excellent biomechanical features (Fig.2) while a sufficient degree of cross-linking was demonstrated through an adequate shrinkage temperature. Furthermore, a significant degree of bacterial adhesion (86% inhibition evaluated with S. aureus) and thrombus formation (Fig.2, up to 90% inhibition) were observed.

Conclusion
There is a real clinical need for improved chemical stability, calcification resistance, and immunological tolerance of current BHVs (surgical and transcatheter). PP technology may substitute the use of GA extending their performance and durability, thereby opening trans-catheter heart valves to younger patients. Reducing the need for mechanical heart valves would also address the associated risks of lifelong anticoagulation therapy.Figure 1Figure 2
Utilizing cluster analysis of biomarkers alongside echocardiographic deformation parameters to forecast the outcome of atrial fibrillation post-ablation
Authors: Huang T C , Huang M , Lee P T , Li Y H 
Published: October 2024

Abstract

Background
Atrial fibrillation (AF) management often involves catheter ablation, but its recurrence necessitates careful clinical management and potential adjustments in medication or further ablation procedures. This study aims to investigate the predictive value of biomarkers and echocardiographic parameters for early AF recurrence.

Methods
In the prospective study, we enrolled patients with symptomatic paroxysmal or persistent atrial fibrillation undergoing catheter ablation. Pulmonary vein isolation was performed in every index procedure, with additional ablation or substrate modification as per physician preference. Blood samples were collected from both the atrium and peripheral vein to assess levels of tumor endothelial marker 1 (TEM1), galectin 3, connective tissue growth factor (CTGF), transforming growth factor-beta (TGF-β), C-terminal propeptide of procollagen type I (PICP), and Smad3. Pre-procedural echocardiographic parameters, including the E/e’ ratio, peak atrial longitudinal strain (PALS), and peak atrial contractile strain (PACS), were recorded. Clustering models with sparse canonical association analysis (CCA) were employed to develop predictive models integrating biomarker and echocardiographic data for early atrial fibrillation recurrence.

Results
Out of 80 prospectively enrolled patients, 68 completed the study, with six cases of early atrial fibrillation recurrence observed. Following dimension reduction and clustering, we found that the combined use of biomarkers and echocardiography significantly predicted atrial fibrillation recurrence (HR: 9.44, p=0.05, 95% CI: 1.0-88.9). Notably, among these parameters, TEM1 biomarker sampled from the peripheral vein (p=0.02), left atrium dimension (p=0.07), and left ventricle dimension (p=0.02) exhibited the most significant predictive power.

Conclusions
Our study highlights the effectiveness of integrating biomarkers and echocardiography parameters in predicting early recurrence of atrial fibrillation post-ablation in patients undergoing catheter ablation.main_figure
Inhibition of ketohexokinase prevents fructose-induced insulin resistance and endothelial dysfunction in high fat and sucrose-fed mice via enhancing energy expenditure
Authors: Viswambharan H , Visnagri A , Bonthron D T , Kearney M T 
Published: October 2024

Abstract

Introduction
Cardiovascular disease linked to fatty liver poses a significant threat to health. Consumption of high-fat diets (HFD) is known to trigger a cascade of health issues including obesity, diabetes and non-alcoholic fatty liver disease (NAFLD). These conditions are exacerbated, with the addition of dietary sugar to high-fat diets (HFSD), resulting in non-alcoholic steatohepatitis (NASH). Studies have shown that fructokinase (ketohexokinase or KHK) knockdown protects mice from HFSD-induced NASH.

Purpose
This study focused on examining the temporal changes of metabolic perturbations, triggered by sugar consumption, particularly in the transition from fatty liver to cardiovascular disease.

Methods
C57/BL6 wild type (WT) and KHK-knockout mice were fed with HFD or HFSD for different durations between 6 to 20 weeks, to induce NAFLD and NASH. Western blotting and quantitative-PCR were carried out on tissues and isolated endothelial cells for protein and mRNA expressions, respectively. Glucose and insulin tolerance tests and whole-body energy measurements were performed at different time-points. Combined Laboratory Animal Monitoring System was used to monitor various parameters of energy expenditure. Functional interactions between endothelial cells and adipose tissues were carried out using an in-house Organ-On-a-chip technology. Endothelial function was studied by measuring isometric tensions in organ bath.

Results
KHK-deficient mice had significantly lower weight compared to WT littermates. Wild-type mice fed HFD and HFSD exhibited significant glucose intolerance, insulin resistance, and endothelial dysfunction compared to KHK-knockout mice. However, HFSD led to more severe outcomes compared to HFD, demonstrating differing temporal effects on glucose intolerance and insulin resistance. Interestingly, KHK-knockout mice were significantly protected from the effects induced by HFSD, as well as, such as increased body weight, fasting hyperglycemia, hyperinsulinemia and endothelial function. KHK-knockout mice exhibited significant increase in oxygen consumption and energy expenditure, both in HFD and HFSD-fed conditions. These data suggest that high energy-expenditure is one of the primary mechanisms, in reducing adiposity and body weight in HFSD-fed knockout mice. Notably, KHK-deficient mice were protected against sugar-induced fat accumulation, random hyperinsulinemia and significant impairment of endothelial function.

Conclusions
A novel finding in this study is that KHK ablation protects not only against HFSD-induced, but also HFD-induced pathologies via significantly enhancing energy expenditure. The results suggest that targeting KHK could potentially mitigate the development of fatty liver and cardiovascular diseases, induced by high calorie diets.
cAMP/PKA-mediated in vitro angiogenesis: A novel interplay between PKA, RhoA/ROCK, and VEGFR2 signalling
Authors: Aslam M 
Published: October 2024

Abstract

Background and Aims
Others and we have previously demonstrated that cAMP/PKA signalling stabilise endothelial cell (EC) barrier function via modulating the activities of Rho GTPases, mainly RhoA and Rac1. In the present study we analysed whether cAMP/PKA also modulates EC angiogenesis capacity and whether Rho GTPases are involved in this function.

Methods
The study was carried out on cultured human umbilical vein ECs (HUVECs). RhoA and Rac1 activities were genetically manipulated by lentiviral-mediated over expression of dominant negative (DN) and constitutive active (CA) forms of RhoA and Rac1. Pharmacologically, specific activation and inhibition of PKA was achieved by using cAMP analogue N6-Benzoyl-cAMP (5 mM) and PKI (1 µM), respectively. Pharmacologically, Rac1 was inhibited using NSC 23766 (10 µM) and RhoA was activated using Rho activator I (Cytoskeleton Inc.). In vitro angiogenesis was analysed by 3-D spheroid assay and matrigel tube formation assay.

Results
Pharmacologically, specific activation of PKA induced EC migration (Wound healing assay), tube formation, and 3-D spheroids and potentiated the VEGF-induced in vitro angiogenesis. These pro-angiogenesis activities were abrogated by highly specific cell-permeable peptide inhibitor (PKI) of PKA. Activation of cAMP/PKA-signalling resulted in an increased VEGFR2 and Akt phosphorylation, increased Rac1 activity, and a strong inhibition of RhoA/Rock pathway. Pharmacological activation of RhoA but not inhibition of Rac1 abrogated PKA-induced VEGFR2 phosphorylation, tube formation and 3-D spheroids. Lentiviral mediated over-expression of constitutive active form of RhoA but not Rac1 abrogated PKA-induced VEGFR2 and Akt phosphorylation and angiogenesis. Moreover, pharmacological inhibition of Akt also abrogated PKA-mediated VEGFR2 phosphorylation and angiogenesis. Likewise, over expression of either dominant negative RhoA or pharmacological inhibitors of Rho kinase (ROCK) promoted basal and potentiated PKA-mediated VEGFR2 and Akt phosphorylation and angiogenesis.

Conclusion
We describe for the first time a novel interplay between PKA, RhoA/ROCK, Akt, and VEGFR2 signalling and angiogenesis. Inhibition of RhoA/ROCK plays an important role in mediating PKA-induced angiogenesis and activation of RhoA/ROCK signalling may offer an important target to intervene therapeutic angiogenesis.
High uric acid induces vascular endothelial cell injury via XBP1-PKM2 mediated glycolytic inhibition
Authors: Shali S , Gao Y B , Zeng L Z , Zhou P , Dai Y X 
Published: October 2024

Abstract

Background/Introduction
Although not fully understood, hyperuricemia induced endothelial dysfunction exhibits at the early onset of the pathology of atherosclerosis. Since aerobic glycolysis is the predominant energy source of endothelial cells, exploring the key glycolytic regulators that are responsible for maintaining the integrity of endothelial barrier may confer vascular homeostasis and prevent atherosclerosis.

Purpose
We aimed to investigate the role of high uric acid in the glycolysis of human umbilical vein endothelial cells (HUVECs), and reveal its potential molecular mechanism underlying endothelial cell injury early in their quiescence.

Methods
Glycolytic metabolism was determined by real-time extracellular flux analysis and seahorse test on the HUVECs exposed to high uric acid (600 and 800μmol/L). We examined the expression of pyruvate kinase muscle isoforms 2 (PKM2), a key enzyme of glycolysis, and transcription factor X-box binding protein 1 (XBP1), which was identified by RNA sequencing and chromatin immunoprecipitation combined with luciferase assay. Then, the effect of glycolytic regulation on the HUVECs functions under hypeuricemic condition was evaluated by molecular manipulating of XBP1-PKM2 signaling pathway.

Results
We observed that hyperuricemia inhibited glycolysis and led to reduced ATP production of HUVECs in vitro by inhibiting the expression of PKM2. In addition, both unsliced and sliced XBP1-(u/s) were also downregulated under the stimulation of high uric acid. Overexpression of XBP1-s increased the transcriptional level of PKM2 via binding the PKM2 promoter, and effectively recovered the glycolitic activity and ATP synthesis. Moreover, upregulating the XBP1-PKM2 pathway mitigated the HUVECs injury induced by hyperuricemia, including the abnormal release of endothelin-1, von Willebrand Factor, reactive oxygen species and nitric oxide, and poor cell proliferation, migration as well as tube formation.

Conclusions
Our data reveal that high uric acid induces HUVECs injury by downregulating glycolysis through the XBP1-PKM2 signaling axis.
Thrombin generation, fibrin clot permeation and lysis in patients with severe mitral regurgitation undergoing transcatheter edge-to-edge mitral valve repair: mitral fibrin study
Authors: Siniarski A , Stepien K , Golinska-Grzybala K , Trebacz J , Stapor M , Szlosarczyk B , Wozniak A , Gajos G , Nessler J , Legutko J , Gackowski A 
Published: October 2024

Abstract

Background/Introduction
The management of heart failure (HF), particularly in the context of reduced ejection fraction, is further complicated by an increased risk of thromboembolic events. Structural alterations of both left ventricle and mitral valve contribute to mitral regurgitation (MR). However, the body of evidence provides inconclusive insights into the relationship between MR and thromboembolic risk.

Purpose
This study aimed to investigate the impact of transcatheter edge-to-edge repair (TEER) on thrombin generation, clot permeation and clot lysis time in HF patients with severe MR eligible for mitral TEER.

Methods
A cohort of 31 HF patients with severe MR undergoing TEER underwent systematic evaluation at three time points. Coagulation parameters, including fibrinogen concentration, thrombin generation, fibrin clot permeability (Ks), and clot lysis time (CLT), were assessed. Comprehensive evaluations also covered echocardiographic, laboratory, and clinical parameters.

Results
TEER induced changes in fibrinogen levels (p=0.009, visit 3 vs. visit 2) and improved fibrin clot properties over a 50-day follow-up (Ks, p=0.005, visit 3 vs. visit 2). No significant differences were observed among time points in analyzed blood clot parameters. Linear regression, incorporating thrombin generation variables, Ks, and CLT for delta NT-proBNP, highlighted CLT as the sole predictor of NT-proBNP change between visit 2 and visit 1 (p=0.03; R2=0.18).

Conclusions
MR reduction through TEER led to transient alterations in fibrinogen concentration and improved fibrin clot characteristics. Additionally, baseline CLT emerged as a significant predictor of early NT-proBNP reduction, emphasizing its role as a key indicator of the hemodynamic response to TEER.
Sphingosine-1-phosphate reduces arterial thrombosis via enhanced endothelial thrombomodulin expression by S1PR1 signaling
Authors: Benkhoff M , Mourikis P , Barcik M , Dahlmanns J , Huckenbeck T , Knoop B , Trojovsky K , Ahlbrech S , Helten C , Dannenberg L , Hohlfeld T , Zeus T , Kelm M , Levkau B , Polzin A 
Published: October 2024

Abstract

Background
Sphingosine 1-phosphate (S1P) is an important lipid mediator in the cardiovascular system. Numerous links between S1P and blood coagulation have been described. However, results regarding the role of S1P in coagulation are inconclusive. A physiological antithrombotic regulator expressed by endothelial cells (EC) is thrombomodulin (TM). To date, the impact of S1P on TM-expression is unknown.

Methods
We evaluated S1P effects on TM-expression and subsequent platelet adhesion and thrombus formation. For this, we conducted cell culture with human umbilical cord venous endothelial cells (HUVECs), flow cytometry and flow chamber experiments. Additionally, in vivo arterial thrombus formation in mice was analyzed.

Results
Sphingosine kinase-1 deficient mice (SphK1-/-) have about 70% less circulating plasma S1P and show a significant reduction in TM expression on the aorta as compared to their littermates (WT: 207.2 ± 45.8 pg/g Aorta vs. SphK1-/- 124.5 ± 40.2 pg/g Aorta, p&lt;0.0001). In contrast, S1P incubation of 24 hours significantly increased TM-expression on HUVECs by about 30 percent. This effect was abolished by S1PR1-inhibition with W146. Treatment with S1P reduced platelet adhesion from whole blood to endothelial cells in the flow chamber experiments (Con: 100.00 ± 28.09% vs. S1P: 80.91 ± 22.85%, p&lt;0.0001). This effect could be reversed both by S1PR1 inhibition and with a TM-neutralizing antibody. P-selectin-expression on platelets was decreased after incubation with TM suggesting (Ctrl: 62.79 ± 13.30% vs. TM: 43.47 ± 11.36%, p=0.0222). Finally, to assess the in vivo effects of our findings, arterial thrombus formation in mice was performed. TM inhibited in vivo thrombus formation. Occlusion of the carotid artery could not be detected during the 30 minutes recording. In contrast, SphK1-/- mice with low S1P levels showed decreased times to first occlusion. Treatment with TM in these animals was able to reverse this effect.

Conclusion
We can conclude that the main findings of our study were (i) S1P increased endothelial TM-expression, (ii) which subsequently leads to reduced platelet adhesion and (iii) inhibition of arterial thrombus formation in vivo.
Genetically Engineered Clostridium Prevents Perivascular Adipose Tissue and Endothelial Senescence and Dysfunction in Aging
Authors: Saeedi S , Pugin B , Constancias F , Thomas A , Le Gludic S , Menni C , Beer J H , Paneni F , Ruschitzka F 
Published: October 2024

Abstract

Introduction
(Peri)vascular senescence is a bona fide risk for several aging-associated diseases that threatens healthspan. Gut microbiome may be one of triggers that promotes vascular diseases as host ages. However, the interplay between vascular senescence and gut microbiome is largely unknown. Our recent studies revealed an increase in gut-derived phenylacetic acid (PAA) in the aging population (TwinsUK Aging Cohort, n=7,303) and aged mice. Our preliminary shotgun metagenomics also showed that ppfor-harboring Clostridium sp. ASF356 age-dependently generates PAA, which induces perivascular adipose tissue (PVAT) and endothelial cell (EC) senescence and dysfunction in old mice. Yet, it remains unclear whether and how genetic engineering of Clostridium sp. ASF356 (by depleting ppfor gene) can prevent aortic PVAT-EC senescence and restore vascular function in aging.

Methods
For bacterial genetic engineering, we depleted ppfor gene in Clostridium ASF356 by ClosTron technique and further mono-colonized aged mice (24-months old) and germ-free mice, as control, to reduce plasma PAA and thereby prevent aortic PVAT-EC senescence and improve endothelial dysfunction.

Results
As a proof of the concept, our studies exhibited that mono-colonization of germ-free mice with wild-type Clostridium sp. ASF356 markedly elevates plasma PAA levels. It was accompanied by hallmarks of aortic PVAT-EC senescence, including increased DNA damage (↑ γ-H2A.X phosphorylation), heightened SASP (↑ IL-6 and VCAM1), and proliferative arrest (↑ p16INK4a and p21WAF1/Cip1). Additionally, our findings revealed upreglation of Notch1 in PVAT, contributing to reduced energy supply (↓ UCP1) and augmented senescence-messaging secretome (↑ IL-6) towards ECs.
Our further studies revealed that mono-colonization of aged mice (pre-treated with antibiotics) with Δppfor Clostridium ASF356 mutants intriguingly resulted in decreased plasma PAA levels. This intervention led to the rescues of cellular senescence in both aortic PVAT and ECs, consequently improving vascular function. Specifically, mice subjected to this treatment exhibited a significant reduction in SA-β-galactosidase+ cells, as well as decreased levels of γ-H2A.X phosphorylation, p16INK4a, p21WAF1/Cip1, and IL-6 in their aortic PVAT and ECs compared to wild-type aged mice.

Conclusions
The current study suggests that genetically engineered Δppfor Clostridium ASF356 mutants reverse cellular senescence and restore function in aortic PVAT and endothelial cells, highlighting the potential for targeted gut microbiome manipulation as an innovative senotherapy to combat vascular aging.