bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hypertension-induced cardiac pro-arrhythmic disorders of connexin-43 and extracellular matrix are attenuated in hairless versus wild-type of spontaneously hypertensive rats
Authors: Andelova K , Sykora M , Szeiffova Bacova B , Farkasova V , Stankovicova T , Knezl V , Pravenec M , Tribulova N 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Development Agency under the contract no. 21-0410
VEGA grants no. 2/0002/20, 2/0006/23

Background
Mechanical dysfunction and occurrence of malignant ventricular fibrillation (VF) are hallmarks of hypertensive heart disease and major health issue. Spontaneously hypertensive rats (SHR) that imitates human primary hypertension are prone to develop VF, mainly due to myocardial remodelling associated with disorders of electrical coupling protein connexin-43 (Cx43) and extracellular matrix (ECM) resulting in electrical instability. However, it is not known whether postnatal acclimation of hairless strain of SHR to surrounding temperature may induce cardio-protection. Therefore, we aimed to explore Cx43 and ECM alterations as well as susceptibility to inducible VF in hairless versus wild type SHR.

Design and Methods
Six-month-old wild type SHR males and females and hairless SHR housed at standard 22°C were examined. Biometric parameters, including electro- and echocardiography were registered. Left ventricular tissue was used for immunolabeling of Cx43 to reveal its topology and for western blotting to determine protein levels of Cx43 and its function modulating protein kinases, PKCε, PKCδ and PKCα as well as for ECM markers, TGF-β, SMAD2/3, MMP-2, collagen-1 and its histological deposition. Susceptibility of the heart to electrically-inducible VF was tested using isolated perfused heart technique.

Key results
Comparing to wild type males, hairless SHR exhibited less pronounced prolongation of QT and QRS interval as well as an increase of ejection fraction. Myocardial Cx43 and its variant phosphorylated at serine-368, which preserve electrical coupling, were increased and pro-arrhythmic cardiomyocyte Cx43 topology was attenuated in males and females hairless vs wild type SHR. Moreover, the level of β-catenin, which ensures mechano-electrical coupling, was also increased in hairless SHR. On the other hand, collagen-1 and hydroxyproline were lower and the TGF-β1 and SMAD2/3 proteins were suppressed in males hairless vs wild type SHR. Myocardial ECM remodelling was less pronounced in females regardless rat strain. Hairless SHR males were less susceptible to inducible VF compared to wild type SHR, while females were less prone to develop VF regardless the strain.
In conclusion, our findings imply that postnatal acclimation of hairless SHR is accompanied by attenuation of hypertension-induced adverse down-regulation of Cx43 and up-regulation of extracellular matrix proteins. It may contribute, at least in part, to the protection from malignant cardiac arrhythmias and mechanical dysfunction.
Alterations in oxidative phosphorylation complexes in arrhythmogenic cardiomyopathy using desmosomal KO cell model
Authors: Artigas Meleiro E , Vallverdu-Prats M , Brugada R , Alcalde M 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III (Fondo Investigación Sanitaria FIS)

Introduction
Arrhythmogenic cardiomyopathy (ACM) is an inherited disease that predominantly affects the right ventricle characterized by progressive cardiomyocyte loss and the replacement of the myocardium by fibro-fatty tissue, which can lead to sudden cardiac death (1). The main genetic causes of ACM are variants in desmosomal genes (PKP2, DSP, DSG2, DSC2 and JUP), representing up to 50% of patients (2).
We lack sufficient understanding at molecular level of the pathophysiological mechanisms that may trigger ACM and determine its progression. Recent studies have proposed a deficit in transcripts encoding for proteins from the electron transport chain, which may be a potential ACM molecular signature in samples from patients with ACM carrying mutations in PKP2 (3).

Purpose
Our study aims to deepen into the knowledge of this proposed mechanism in PKP2 deficiency using edited cell model and elucidating whether these mechanisms are also triggered in DSG2 and DSC2 deficiency, being a potential common ACM pathomechanism, or they are gene specific.

Methods
HL-1 edited cell lines for desmosomal genes previously generated by CRISPR/Cas9 (PKP2-KO, DSC2-KO and DSG2-KO) in our research group were used to perform our analysis (4). Expression profiling was performed by RNA-seq analysis.
To experimentally validate the RNA-seq analysis results, we performed western blot assays using total protein lysate to test protein levels of the five oxidative phosphorylation (OXPHOS) complexes for the PKP2-KO, DSC2-KO and DSG2-KO groups. To test if these differences have an impact at functional level, XFp cell Mito Stress Test (Agilent Technologies) was performed.

Results
RNA-seq analysis results showed numerous downregulated pathways related to aerobic respiration, the electron transport chain, oxidative phosphorylation and ATP synthesis in all three desmosomal KO lines.
Our experimental results showed a significant reduction of the OXPHOS complexes of the mitochondrial respiration chain at protein level in all PKP2-KO, DSC2-KO and DSG2-KO (Fig. 1).
At functional level, our preliminary results of Mito Stress Test suggest differences in basal and maximal respiration, ATP production, non-mitochondrial oxygen consumption and spare respiratory capacity between experimental groups.

Conclusions
Our results support previously published studies describing oxidative phosphorylation as a pathomechanism for PKP2 deficiency and also suggest that these mechanisms may be a common feature for desmosomal mutations in ACM.Total expression of OXPHOS complexes
Human in vitro disease modeling of ATTR cardiac amyloidosis
Authors: Qin J , Dokter I , Qiang Y , Lei Z , Sluijter J , Oerlemans M , Van Mil A 
Published: May 2024

Abstract
Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Pfizer Alnylam
Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive disease with deposition of TTR amyloid fibrils in the myocardium and cardiac dysfunction with dismal prognosis. In ATTR-CM, either genetic mutations (variant; v) or ageing (wild-type; wt) leads to TTR instability. Late diagnosis and a lack of human disease models limit disease understanding and therapeutic discovery.
This study aimed to model ATTR-CM in vitro by exposing various cardiac cell types and multicellular 3D cardiac spheroids to TTR fibrils, characterizing disease phenotypes and providing insights into the cellular mechanisms of disease progression.
Human recombinant TTR (WT, V30M, V122I) and acid induced fibrils were generated and characterized. Seeding hiPSC-cardiomyocytes (CMs) and endothelial cells (ECs) on TTR fibrils resulted in cell viability reduction. Confocal microscopy revealed the extracellular attachment of TTR fibrils, leading to sarcomere disorganization, prolonged calcium transients and disrupted electromechanical coupling in hiPSC-CMs, and declined migration capacity of ECs showing aberrant cell morphology. Similarly, cardiac spheroids incorporating TTR fibrils resulted in decreased cell viability and prolonged calcium transients with lower amplitude.
Our models show the discovery of early cellular ATTR-CM phenotypes, providing a novel approach to study the disease progression, potentially facilitating the identification of novel therapeutic targets and biomarkers.Cytotoxicity of TTR fibrils on hiPS-CMs
High-throughput proteomic analysis unveils metabolic and mitochondrial signaling rewiring by chronic ivabradine treatment in duchenne muscular dystrophy
Authors: Dostal C , Szabo P L , Marksteiner J , Podesser B K , Hilber K , Kiss A 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Austrian Science Fund (FWF)

Objective
Ivabradine (IVA) is indicated in symptomatic treatment of chronic stable angina, heart failure, and also in those who are unable to tolerate or have contraindications to the use of beta-blockers. It has been showed IVA may have cardiovascular benefits in Duchenne muscular dystrophy (DMD) patients. This study was aimed to investigate the sustained impact of chronic ivabradine (IVA) administration on cardiac function and potential underlying mechanism using high throutput proteomic analysis.

Methods
DMDmdx male and Sprague–Dawley wt (Sprague–Dawley) male rats were randomly allocated to vehicle (n = 6) or IVA (n=6; 10 mg/kg/day via drinking water for four months). Transthoracic echocardiography and unbiased proteomic analysis were performed to assess cardiac function and left ventricular (LV) tissue, respectively. Protein-protein interactions were graphically represented, and cluster analysis with subsequent enrichment analyses was conducted.

Results
Chronic IVA treatment significantly enhanced the LV ejection fraction (p&lt;0.05 compared to vehicle-treated DMDmdx rats). Proteomic data identified possible transcription factors (SPI1, IRF1, PPARA), consistent with previous studies. The reduction in copper metabolic changes associated with DMD can be attributed to the upregulation of Atox1 following IVA treatment. Mitochondrial dysfunction was effectively mitigated by IVA, as indicated by the different abundance of mitochondrial proteins. In addition, intercellular adhesion molecule 1 showed a reduction in the number of animals treated with ivabradine, indicating a further positive effect of the treatment.

Conclusion
In summary, this study demonstrated the beneficial effects of IVA in DMDmdx rat hearts. Cluster analysis of proteomic data revealed notable changes in cardiac metabolism, inflammation, and mitochondrial function. Ivabradine has emerged as a potential therapeutic approach to address these shifts, while proteomic pathway analysis may uncover new drugable targets to alleviate cardiomyopathy progression in DMD.Interaction of IvabradinProtein-protein interaction network
Zebrafish dspb-/- mutant as model for arrhythmogenic cardiomyopathy - impact of physical activity
Authors: Munteanu S , Wagih Gomez J , Nicolas Rocamora E M , Gil Ortuno C , Bernabe Garcia A , Judez Serrano A , Martinez Perez C , Gimeno Blanes J R , Cayuela Fuentes M L , Sabater Molina M 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Instituto de Salud Carlos III

Background
Zebrafish has been reported as a model to study the Arrythmogenic cardiomyopathy, which is generally associated with desmosomal gene mutations. We have identified a founder non-sense human variant in patients from our region (DSP p.Q447*) associated with left ventricle Arrythmogenic cardiomyopathy and we have selected it for modelling in zebra fish by CRISPR/Cas9 method, choosing exon 10 as the region of homology to be mutated and obtaining the p.T449fs* variant that determines a premature stop codon.

Purpose
Our aim was the characterization of dspb-/- mutants, studying the impact of physical activity in development of the disease.

Methods
The characterization of phenotype was performed through viability assays, cardiac function measurements and gene expression assays in larvae (3 days post fertilization) and adult (8 months old) individuals. The impact of physical activity was determined through moderated training periods (1 month) and endurance assays using a swimming tunnel.

Results
Viability assays showed that dspb mutants suffer a premature death, with significant higher mortality rates than the wildtype group (survival WT 89.7% vs dspb-/- 61.3%, p&lt;0.01). Larvae cardiac function showed dspb mutants had a higher heart rate (WT 106.8 ± 26.8 vs dspb-/- 141.0 ± 7.2, p&lt;0.01) while echocardiography showed differences in heart rate (WT 127.2 ± 49,8 vs dspb-/- 219.2 ± 26.8, p&lt;0.05), systolic (WT 26.9 ± 5.3 vs dspb-/- 18.5 ± 5.2, p&lt;0.05) and diastolic (WT 37.6 ± 8.4 vs dspb-/- 23.7 ± 5.4, p&lt;0.05) areas. Gene expression analysis in adult heart showed dspb expression drastically decreased (WT 0.9 ± 0.1 vs dspb-/- 0.4 ± 0.01, p&lt;0.01), whilst pkp2 expression increased (WT 0.9 ± 0.1 vs dspb-/- 2.59 ±0.22, p&lt;0.001) as well as dspa gene expression (wt 0.9 ± 0.1 vs dspb-/- 4.41 ± 0.18, p&lt; 0.001) as a compensation mechanism. Moderated long term physical activity had a positive impact in heart rate (dspb-/-pre 219.2 ± 26.8 vs dspb-/-post 138 ± 7.5, p&lt;0.01) and diastolic area (dspb-/-pre 24 ± 5 vs dspb-/-post 32 ± 2.1, p&lt;0.05). Adult mutants showed a better endurance showing improvement in immobile cumulative duration (dspb-/-pre 849.3 ± 29.3 vs dspb-/-post 179.8 ± 29.7, p&lt;0.01) and immobile frequency (dspb-/-pre 5399.5 ± 1127.8 vs dspb-/-post 1310 ± 481.9, p&lt;0.01).

Conclusion
The dspb-/- zebrafish presented pathological cardiac phenotype at larvae and adult stages, and less endurance in intensity exercises. The moderate exercise has turned out to be a beneficial modulator of the phenotype.
Antisense oligonucleotides as a potential therapeutic strategy in hypertrophic cardiomyopathy caused by MYBPC3 variants
Authors: Munteanu S , Nicolas Rocamora E M , Martinez Perez C , Bernabe Garcia A , Nicolas Villaescusa F J , Gimeno Blanes J R , Arechavala Gomeza V , Sabater Molina M 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Sociedad Española de Cardiología

Background/Introduction
Non-sense or frameshift mutations in the MYBPC3 gene encoding cardiac myosin-binding protein C (cMyBP-C) are a major cause for inherited forms of Hypertrophic Cardiomyopathy (HCM), the most frequent inherited cardiac disease, affecting 0.2% of the general population and represents the leading cause for sudden cardiac death in young athletes. During the last decade, RNA-based therapeutic approaches have been studied for neuromuscular disorders and recently became to be considered to envision causal therapies for cardiomyopathies, utilizing antisense oligonucleotide mediated exon skipping, which attempts to reframe mutated mybpc3 transcripts, resulting in shortened but functional protein. MYBPC3 gene has a total of 34 coding exons and, exons 2, 22, and 24-27 are ideal targets for skipping.

Purpose
We aim to design and evaluate antisense oligonucleotides (AONs) for efficient exon-skipping in targeted MYBPC3 exons.

Methods
We designed two specific AONs to mask the MYBPC3 exon 26 and confirmed successfully mediated exon skipping without disrupting the MYBPC3 reading frame. We chose a previously identified MYBPC3 c.2671insG/p.R891Afs*160 variant in exon 26, which causes a frameshift mutation leading to truncated MYBPC3 in HCM. Primary Human Cardiac Myocytes (PHCM) (Promocell) were transfected with the splice-site targeting AONs.

Results
In this study we designed two chemically modified AONs (AON1 and AON2) through the addition of a 2′-O-methyl RNA phosphorothioate backbone, targeting exonic splicing enhancers (ESEs) or splice sites (SSs) can induce skipping of MYBPC3 exon 26.
We evaluated AON1 (i26-3SS) and AON2 (ESE)-treated Primary Human Cardiac Myocytes (PHCM) show 26-27 exons skipping in comparison to control samples. The identity of the exon 26-27 skipped bands detected by RT-PCR was confirmed by Sanger sequencing and preservation of both nucleotide sequences of MYBPC3 exons 25 and 28 were observed.
These results indicate that AONs specifically for mutated MYBPC3 target exons, expanding the framework of future advancements in the therapeutic potential of antisense-mediated exon skipping MYBPC3-based HCM. In addition, skipping exons 26 and 27 we eliminate a total of 22 possible exonic mutations, which represent 7.2% of the total known MYBPC3 exonic mutations.

Conclusion(s)
These results demonstrate that disruption of the MYBPC3 reading frame due to a truncating HCM mutation can be restored by exon skipping in cardiomyocytes in vitro indicating RNA-based strategies as a potential treatment option for HCM.Exon skipping scheme
Connecting the dots: molecular pathways in bicuspid aortopathy explored
Authors: Pozo-Vilumbrales B , Soto-Navarrete M T , Martin-Chaves L , Lopez-Unzu M A , Pavon-Moron J , Rodriguez-Capitan J , Fernandez B 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Junta de Andalucía, Ministerio de Ciencia e Innovación

Background
Bicuspid aortic valve (BAV) is the most common congenital cardiac malformation. It predisposes to thoracic aortic dilatation (TAD), aneurysm and dissection. The current consensus is that the genetic defect that leads to the aortic valve malformation also causes structural anomalies of the ascending aorta. Altered hemodynamics caused by the abnormal valve morphology would accelerate aortic media degeneration. Molecular markers and pathways involved in the aetiology and pathophysiology of bicuspid aortopathy are poorly understood.

Objective
To elucidate the molecular and cellular mechanisms of the disease and to identify potential predictive molecular markers using a well-established isogenic hamster model (T strain) with a high (∼40%) incidence of BAV TAD.

Methods
Comparative quantitative proteomics combined with Western blot and morpho-molecular analyses in the ascending aorta of tricuspid aortic valve (TAV) and BAV animals from the T strain and TAV animals from a control strain. This strategy allows exploring independently the genetic and hemodynamic effects on the aorta in genetically homogeneous populations.

Results
The major molecular defect in the aorta of genetically homogeneous BAV individuals is PI3K/AKT overactivation caused by alterations in the EGF, ANGII and TGF-β signalling pathways. PI3K/AKT affects the downstream eNOS, MAP2K1/2, NF-κB, mTOR and WNT pathways. Most of these alterations are seen in independent patient studies with different clinical presentations, but not in TAV hamsters from the T strain, which mainly show downregulation of the WNT pathway.

Conclusions
We identify a combination of defective interconnected molecular pathways, directly linked to the central PI3K/AKT pathway, common to both BAV-associated TAD patients and hamsters. The defects indicate a shift of smooth muscle cells towards the synthetic phenotype induced by endothelial-to-mesenchymal transition, oxidative stress and inflammation. WNT signalling represents a genetic factor that may cause aortic structural abnormalities and aneurysm predisposition, whereas hemodynamics is the main trigger of molecular changes, likely determining the progression of aortopathy. We identify twenty-seven novel potential biomarkers with high predictive value.
Short- and long term preservation of cardiac tissue-engineered constructs
Authors: Janssen J , Chirico N , Ainsworth M , Viola M , Cedillo-Servin G , Vermonden T , Doevendans P , Serra M , Voets I , Malda J , Castilho M , Laake L , Sluijter J , Sampaio-Pinto V , Van Mil A 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): This research was financially supported by the Gravitation Program ‘‘Materials Driven Regeneration,’’ funded by the Netherlands Organization for Scientific Research (024.003.013) and the EU-funded project BRAV∃ (H2020, ID:874827).

Background
Cardiac tissue engineering (cTE) has already advanced towards the first clinical trials, investigating safety and feasibility of cTE construct transplantation in failing hearts. However, the lack of well-established preservation methods poses a hindrance to further scalability, commercialization, and transportation, thereby reducing their clinical implementation.

Purpose
In this study, hypothermic (short-term) preservation (4°C), and slow and fast freezing methods for cryopreservation, at -196°C and -150°C respectively, were investigated as potential solutions to extend the cTE construct implantation window and increase their clinical applicability.

Material and Methods
The cTE model used consisted of induced-pluripotent stem cell-derived cardiomyocytes and human cardiac fibroblasts embedded in a natural-derived hydrogel and supported by a polymeric melt electrowritten hexagonal scaffold. Constructs, composed of cardiomyocytes of different maturity, were preserved for three days, using several commercially available preservation protocols and solutions. Their viability, function (BPM and calcium handling), and metabolic activity were investigated after rewarming.

Results
Our observations suggest that cardiomyocyte maturation did not influence post-rewarming viability, however, aging positively influenced construct function pre- and post-storage. Hypothermic preservation in Hypothermosol ensured retained construct viability and function. Furthermore, fast-freezing outperformed slow-freezing, but both viability and function were severely reduced after rewarming.

Conclusion
In conclusion, whereas long-term preservation remains a challenge, hypothermic preservation in Hypothermosol represents a promising solution for cTE construct short-term preservation and potential transportation, aiding in off-the-shelf availability, ultimately increasing their clinical applicability.Graphical abstract
Lower activity of cholesteryl ester transfer protein (CETP) and the risk of dementia: a Mendelian randomization analysis
Authors: Schmidt A , Davidson M H , Ditmarsch M , Kastelein J J , Finan C 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): New Amterdam Pharma

Background
Elevated levels of low-density lipoprotein cholesterol (LDL-C) are linked to dementia risk, and conversely, increased plasma concentrations of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein-A1 (Apo-A1) associate with decreased dementia risk. Inhibition of cholesteryl ester transfer protein (CETP) meaningfully affects the concentrations of these blood lipids and may therefore provide an opportunity to treat dementia.

Methods
Drug target Mendelian randomization (MR) was employed to anticipate the on-target effects of lower CETP concentration (µg/mL) on plasma lipids, cardiovascular disease, Lewy body dementia (LBD), as well as Parkinson’s dementia. Replication was sought by performed Apo-A1 and Apo-B weighted MR analyses of CETP variants. Genetic associations with protein expression in cerebrospinal fluid (CSF) and brain were consulted to identify potential associations of plasma CETP with dementia implicated proteins.

Results
MR analysis of lower CETP concentration (per µg/mL) recapitulated the blood lipid effects observed in clinical trials of CETP-inhibitors, as well as protective effects on CHD (odds ratio (OR) 0.92, 95% confidence interval (CI) 0.89; 0.96), heart failure, abdominal aortic aneurysm any stroke, ischemic stroke, and small vessel stroke (0.90, 95%CI 0.85; 0.96); Figure. Consideration of dementia related traits indicated that lower CETP concentrations were associated higher total brain volume (0.04 per standard deviation, 95%CI 0.02; 0.06), lower risk of LBD (OR 0.81, 95%CI 0.74; 0.89) and Parkinson’s dementia risk (OR 0.26, 95%CI 0.14; 0.48). APOE4 stratified analyses suggested the LBD effect was most pronounced in APOE-ε4+ participants (OR 0.61 95%CI 0.51; 0.73), compared to APOE-ε4- (OR 0.89 95%CI 0.79; 1.01); interaction p-value 5.81×10-4. The aforementioned associations were replicated using Apo-B and Apo-A1 weighted analyses; Figure. Additionally, MR was employed to link plasma CETP concentration to the levels of CSF and brain proteins such as EPHA2 and CSF-1, which are in development as dementia drug targets.

Conclusion
These results suggest that inhibition of CETP may be a viable strategy to treat dementia.