bluuebunny/crossref_metadata_2025_split huggingface dataset:
Verification of a simplified aneurysm dimensionless flow parameter to predict intracranial aneurysm rupture status
Authors: Yang Runlin , Ren Yifan , Kok Hong Kuan , Smith Paul D , Kebria Parham Mohsenzadeh , Khosravi Abbas , Maingard Julian , Yeo Melissa , Hall Jonathan , Foo Michelle , Zhou Kevin , Jhamb Ashu , Russell Jeremy , Brooks Mark , Asadi Hamed 
Published: May 2024

Abstract

Objectives
Aneurysm number (An) is a novel prediction tool utilizing parameters of pulsatility index (PI) and aneurysm geometry. An has been shown to have the potential to differentiate intracranial aneurysm (IA) rupture status. The objective of this study is to investigate the feasibility and accuracy of An for IA rupture status prediction using Australian based clinical data.

Methods
A retrospective study was conducted across three tertiary referral hospitals between November 2017 and November 2020 and all saccular IAs with known rupture status were included. Two sets of An values were calculated based on two sets of PI values previously reported in the literature.

Results
Five hundred and four IA cases were included in this study. The results demonstrated no significant difference between ruptured and unruptured status when using An ≥1 as the discriminator. Further analysis showed no strong correlation between An and IA subtypes. The area under the curve (AUC) indicated poor performance in predicting rupture status (AUC1 = 0.55 and AUC2 = 0.56).

Conclusions
This study does not support An ≥1 as a reliable parameter to predict the rupture status of IAs based on a retrospective cohort. Although the concept of An is supported by hemodynamic aneurysm theory, further research is needed before it can be applied in the clinical setting.

Advances in knowledge
This study demonstrates that the novel prediction tool, An, proposed in 2020 is not reliable and that further research of this hemodynamic model is needed before it can be incorporated into the prediction of IA rupture status.
CDK4/6 inhibitor ribociclib induces cardiotoxicity in dynamic engineered heart tissues, mitigated by E2F1 overexpression
Authors: Linders A , Dias I , Meyer C , Jagersma R , Deiman F , Zhu J , Feinberg A , Bomer N , Van Der Meer P 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Research Council
CDK4/6 inhibitor Ribociclib induces cardiotoxicity in dynamic engineered heart tissues, mitigated by E2F1 overexpression

Background
Ribociclib, a novel chemotherapeutic agent for metastatic breast cancer, functions as a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor1. Its mechanism of action involves the CDK4/6-Rb-E2F1 pathway. Ribociclib use has very recently been associated with development of heart failure (HF)2, yet the causality of its cardiac effects remains to be explored.

Aims
This study aims to investigate ribociclib's cardiotoxic effects in dynamic human engineered heart tissues (dyn-EHTs), focusing on the CDK4/6-Rb-E2F1 axis.

Methods and Results
Dyn-EHTs were generated using human induced pluripotent stem cell derived cardiomyocytes (iPSC-CMs) and treated with repeated doses of ribociclib (7 µM) to mimic clinical drug administration. Post-treatment, dyn-EHTs exhibited a 17.0% (p&lt;0.001) increase in tissue dilatation, an 8.9% (p&lt;0.001) decrease in systolic force generation, and a 22.1% (p&lt;0.001) increase in systolic stress, indicating significant cardiac dysfunction. Additionally, an increase in phosphorylation levels of Rb protein (Ser249 and Thr252) was observed (FC=0.445, p=0.009). Overexpression of E2F1 in iPSCs resulted in a threefold increase in E2F1 protein expression and successfully mitigated the ribociclib-induced tissue dilatation (p=0.007), decreased systolic force generation (p=0.005), and increase in systolic stress (p=0.004) making their performance comparable to healthy controls, as shown by linear regression analysis.

Conclusions
Our study demonstrates that ribociclib induces significant cardiotoxic effects in dyn-EHTs and iPSC-CMs through the CDK4/6-Rb-E2F1 pathway. The prevention of these effects by E2F1 overexpression highlights the pathway's involvement in ribociclib's cardiotoxic profile. These findings emphasize the need for careful cardiac monitoring in patients treated with CDK4/6 inhibitors and suggest further research into specific mechanisms of cardiotoxicity in cancer therapeutics.Graphical Abstract
Differential sex-dependent role of lncRNAs in cardiomyopathy
Authors: Franco D , Martinez-Amaro F , Bonet F , Toro R , Perez De Castro I , Rochais F , Bouchard L , Salguero A , De La Pompa J L , Garcia-Padilla C 
Published: May 2024

Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Education and Science
Cardiovascular diseases are one of the most prevalent causes of mortality and morbidity worldwide. Structural diseases such as dilated and hypertrophic cardiomyopathy significantly contributed to it. In recent years, several studies have pinpointed the importance of non-coding genome in the pathogenesis of cardiomyopathy. We have previously reported the role of distinct lncRNAs in atrial fibrillation. We now explored the plausible role of these lncRNAs in cardiomyopathy by analyzing their expression in two different mouse mutant models of lamin (LMNA) - LMNAR249W and αMHCCreLMNAFF, a cardiac hypertrophic MyBPC3 mutant model as well as in experimental myocardial infarction mice. Importantly, both LMNA mutant models developed a dilated cardiomyopathy, a condition distinctly observed in males but not in females. Our data demonstrated that Walras, Gm26533, Wallrd, Walaa and Walrad are downregulated in females, but not males. Furthermore, differential deregulation is also observed in MyBPC3 mutant model but not in myocardial infarction. In vitro analyses demonstrated an estrogen-dependent regulation. In addition, expression analyses in distinct cardiovascular cell lines revealed enriched myocardial expression of Walras and Gm26533 while Wallrd and Walaa are preferentially expressed in endocardial cells. These data were further validated by in situ hybridization in embryonic cardiac tissues.
Walras overexpression resulted in enhanced expression of two key factors of UPR signaling pathway, i.e. Atf6 and Ire1, while Walras inhibition downregulated them. Upregulation of both UPR factors in Walrasgain-of-function assays is accompanied by increased cardiomyocyte apoptosis. In contrast, Walras inhibition resulted in increased Bcl2 expression and therefore increased cell viability. Mechanistically, Walras directly interacts with calumenin protein, a known protective factor against UPR-associated apoptosis, as demonstrated by pulldown assays. In sum, we demonstrated sex-dependent regulation of distinct lncRNAs in different cardiomyopathic mouse models and at least one of them, i.e. Walras contributes to UPR-associated apoptosis regulation, providing a causative link to the development of distinct cardiomyopathies.
Altered firing activity of intracardiac neurons isolated from mice carrying the Scn5a-1798insD mutation
Authors: Casini S , De Waal T M , Schumacher C , Veldkamp M W , Remme C A 
Published: May 2024

Abstract

Funding Acknowledgements
None.

Background
Dysfunction of the cardiac sodium channel Nav1.5 (encoded by SCN5A) is associated with arrhythmias and sudden cardiac death, the mechanisms of which have been extensively studied in cardiomyocytes. However, patients carrying an SCN5A mutation often display clinical symptoms which are not readily explained solely by alterations in cardiomyocyte electrophysiology. For instance, carriers of the SCN5A-1795insD mutation, which is associated with features of Brugada syndrome and Long QT syndrome type 3 (LQT3), display severe bradycardia leading to excessive QT-prolongation and sudden death especially occurring at rest or during the night, suggesting autonomic triggers. Interestingly, SCN5A is not only present in cardiomyocytes, but also in intracardiac neurons (ICN). ICN modulate cardiac electrophysiological properties and their dysregulation may contribute to arrhythmogenesis.

Purpose
To explore whether ICN from mice carrying the Scn5a-1798insD mutation (the murine equivalent of SCN5A-1795insD) display electrophysiological alterations that may (in part) contribute to the arrhythmogenic phenotype.

Methods and Results
ICN were isolated by enzymatic dissociation from fat pads located in the pulmonary veins and sinoatrial node regions of the hearts of wild-type (WT) and Scn5a-1798insD mice. Immunodetection of the cholinergic marker ChAT confirmed the prominent cholinergic phenotype of ICN. In agreement with previous reports in other species, we also detected the presence of Nav1.5 in murine ICN. Nav1.5 expression was mainly observed in ChAT positive cells. To evoke repetitive action potential (AP) firing in single ICN, 500 ms-sustained depolarizing current pulses were applied of increasing amplitude (from 0 pA to 150 pA). Two types of neurons were identified on the basis of firing pattern characteristics: accommodating (neurons that discharged multiple APs decrementing in frequency during the pulse) and tonic (neurons that discharged multiple APs at a high frequency). APs firing frequency did not differ between WT and Scn5a-1798insD accommodating ICN, while it was significantly increased in Scn5a-1798insD tonic ICN as compared to WT (at 100 pA, AP count/500ms in WT CMs: 29.5±1.7, n=24; at 100 pA, AP count/500ms in Scn5a-1798insD: 36.2±2.0, n=18, p=0.02).

Conclusions
The impact of SCN5A mutations on ICN function are unexplored, but may play an essential role in arrhythmogenesis. The increased AP firing frequency observed in Scn5a-1798insD ICN may lead to increased release of neurotransmitters, such as acetylcholine, that in turn may contribute to the bradycardia observed in patients. Overall, further elucidation of the electrophysiological consequences of inherited Nav1.5 dysfunction in ICN might provide novel therapeutic targets to prevent lethal arrhythmias.
Role of inflammatory populations and their intermediates in post-ischemic adverse remodeling in rat model of myocardial infarction
Authors: Bevilacqua E , Falcon D , Ordonez-Fernandez A , Del Toro R , Smani T 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Junta de Andalucía- Fondos FEDER

Background
Compelling evidence demonstrated the critical role of inflammation in ventricular adverse remodeling after acute myocardial infarction. However, it remains unclear how inflammatory cell population and their intermediates participate in the progress of the disease.

Purpose
This study aims to elucidate the role of inflammatory population in cardiac remodeling after myocardial infarction in a rat model, focusing on their role in fibrosis.

Methods
We used a surgical procedure by transient ligation of the left descendant coronary artery, to evoke ischemia-reperfusion (I/R) in rats. We performed FACS analysis to evaluate counts of neutrophils and two monocytes’ subsets: CD43lowHis48high (classical monocytes), and CD43highHis48low (non-classical monocytes), which are the most pro-inflammatory subset in peripheral blood. Subsequently, we performed immunofluorescence to detect pro-inflammatory M1 and M2 macrophages (CD68+ and CD163+) in the rat infarcted myocardium. Moreover, we sorted the two monocyte subsets and performed genes and microRNAs Array.

Results
FACS analysis of neutrophils and monocytes subsets showed an increased level of these cells in the rat model of myocardial infarction, one week after the post-ischemic event. In parallel, the infiltration of M1 macrophages was increased in the myocardium until 1 week after surgery, indicating a long extravasation of inflammatory cells after the ischemic event. Moreover, co-culture of fibroblasts and cardiomyocytes with intermediates released by inflammatory cells subjected to I/R increased the expression of fibrotic and apoptotic genes. In addition, the analysis of genes’ Array by GSEA indicated that CD43highHis48low monocytes had an enrichment score in pathways associated with angiogenesis, fibrosis and inflammation, while CD43lowHis48high population exhibited an enrichment in cytokines and inflammation, apoptosis and fibrosis. Finally, we found significant overexpression of microRNAs, for instance, miR-27a-3p, miR-29b-3p, miR-30e-5p and miR-194-5p in CD43highHis48low 24h after the I/R procedure. Those miRNAs are predicted to modulate pro-fibrotic genes.

Conclusions
The level of inflammatory cell populations is increased in I/R rat model. Moreover, these cells infiltrate in the myocardium likely to change the transcriptome of resident cells towards a pro-apoptotic and pro-fibrotic phenotype.
Meteorin-like regulates cardiac hypertrophy and associated metabolic plasticity during gestation and lactation
Authors: Blasco-Roset A , Ruperez C , Cerrato E , Villarroya F , Quesada-Lopez T , Planavila A 
Published: May 2024

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministerio de investigación y ciencia de España

Introduction
Pregnancy-induced cardiac hypertrophy is considered a physiological, reversible process (1, 2). However, cardiac remodeling after delivery and through lactation, as well as mechanisms driving hypertrophy reversion, remain undefined. In recent studies, we described the cardioprotective role of Meteorin-like (Metrnl) during pathological remodeling of the myocardium (3). Its role during gestation and lactation in the maternal heart is completely unknown.

Purpose
To characterize pregnancy-induced cardiac hypertrophy and its underlying mechanisms, and to determine the role of Metrnl in the cardiac remodeling associated to pregnancy and lactation.

Methods
C57BL/6J wild-type (WT) and Metrnl knockout (Metrnl-KO) female mice were studied during gestation, lactation and weaning. Echocardiographic measurements and cardiac samples were obtained from virgin control animals (V), pregnant mice at term (E18), lactating females at days 14 and 21 (L14 and L21), and mice 7 and 21 days after L21 weaning (W7 and W21).

Results
In WT females, pregnancy induces eccentric cardiac hypertrophy characterized by a major dilation of the left ventricle, a phenomenon that is maintained and further increased during lactation, reaching the highest degree of eccentric hypertrophy by L14. After weaning, hypertrophy is totally reversed (Figure 1A). By contrast, Metrnl-KO mice show a more pathological cardiac phenotype characterised by an exacerbated eccentric hypertrophy development accompanied by reduced ejection fraction. Post-weaning resolution is also delayed compared to WT. Next, we analysed cardiac metabolism since during the latest stages of gestation, the heart relies more on fatty acid utilization due to the increased glucose demands of the foetus (Figure 1B). We found that in WT mice, cardiac expression of genes linked to fatty acid oxidation (FAO; Acadm, Pdk4 and Cpt1b) is increased during gestation and repressed during lactation in parallel with cardiac Metrnl expression, recovering basal levels by W7. By contrast, in Metrnl-KO mice mitochondrial pyruvate transporter Mpc1 expression is increased during the whole process, while Pdk4 and Cpt1b protein levels are lower, suggesting a reliance of these hearts on glucose metabolism during pregnancy and post-partum.

Conclusions
The maternal heart develops an adaptive pregnancy-induced cardiac hypertrophy, a condition that initiates at gestation, peaks by day 14 of lactation and starts reverting upon weaning. Metrnl is necessary for the correct development of cardiac adaptations associated with pregnancy/lactation.Figure 1
Cryopreservation of human adult ventricular tissue for the preparation of viable myocardial slices
Authors: Lodrini A M , Husetic A , Kok T , Kruithof B P T , Hjortnaes J , Palmen M , Smits A M , Goumans M J 
Published: May 2024

Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): REGeRNA
Myocardial slices are ultra-thin slices of living adult myocardium which can be cultured. As a multicellular 3-D culture model, myocardial slices offer a novel opportunity to investigate how adult cardiomyocytes (CMs) interact with other cardiac cell types and the extracellular matrix, while providing long-term preservation of CMs cytoarchitecture and electrical phenotype. Additionally, myocardial slices are a new tool in drug discovery by allowing to test chronic treatments, as opposed to isolated CMs which are limited to acute timepoints.
Despite their benefits over other cardiac preparations, myocardial slices also have several limitations, of which one is the quality of the slices. The main determinant of myocardial slice quality is the procedure by which the cardiac tissue block is handled. Current methods depend on the preparation of slices directly after tissue excision, therefore limiting the moment when the experiment is performed.
We developed a protocol for the cryopreservation of human adult ventricular tissue allowing preparation of viable myocardial slices afterwards.
Fresh and cryopreserved cardiac tissue from donor hearts was processed and evaluated for viability, tissue integrity, and inflammatory markers using molecular biology and histological assays. The tissue samples retained viability, biomass, and tissue and vascular integrity following cryopreservation compared to fresh tissue. Additionally, we compared myocardial slices obtained from fresh or cryopreserved tissue and cultured for 24 hours. Histologically, normal cytomorphological features and gap junctions between CMs were preserved in all slices. Comparable retention of tissue viability and structural integrity post cryopreservation (4-6 weeks) and culture (up to 7 days) was observed in cardiac samples from 3 additional donors.
In summary, cold storage extends the time-interval between sample collection and slice preparation, allowing for more long-term, complex endpoints. Moreover, efficient banking of cryopreserved cardiac samples from various donors and disease states is critical for regular use of myocardial tissue slices in drug discovery and development. Additional research on the effects of cryopreservation on different cardiac cell types will allow to improve donor organ management to extend the donor pool and increase utilization rate.
LMNA p.Arg624His missense variant reduces lamin expression at mRNA level: elucidating molecular pathways toward cardiac involvement in laminopathies
Authors: Lozano-Velasco E , Morales-Alcazar C J , Martinez-Rodriguez A M , Cano-Carrillo S , Garcia-Ruano A B , Urbano-Moral J A , Franco D 
Published: May 2024

Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science and Innovation
LMNA is a gene encoding lamin A/C proteins of the cell nuclear lamina. Pathogenic variants in LMNA cause a group of diseases known as laminopathies, a common cause of dilated cardiomyopathy (DCM). LMNA is the second most frequently mutated gene in DCM. Although molecular mechanisms underlying the cardiac involvement are unclear, previous studies have shown a reduction of the lamin expression in LMNA heterozygous mutation carriers. We identified a missense variant in LMNA, c.1871G&gt;A (p.Arg624His), in a family affected with DCM. In this study, we analysed the impact of the p.Arg624His variant on the mRNA expression through quantitative PCR (qPCR) to demonstrate its pathogenicity. RNA was isolated from patient’s peripheral blood lymphocytes. Quantitative reverse transcription PCR (RT-qPCR) with LMNA specific primers was performed to measure lamin RNA levels. Whole-exome sequencing (WES) through next-generation sequencing (NGS) yielded an heterozygous missense variant in the LMNA gene (NM_170707.4(LMNA): c.1871G&gt;A; p.Arg624His; ClinVar ID 66870) classified as variant of uncertain significance (VUS) in five members of a family affected with DCM. Computational (In-Silico) programs predict a damaging effect and variant is absent from controls in population databases. RT-qPCR demonstrated a significant reduction in the LMNA mRNA expression between the control (II.1) and affected family members (II.3, III.1) (Figure 2). According to evidence of co-segregation, variant frequency, results of in-silico predictors and mRNA reduction, LMNA p.Arg624His variant has been reclassified as pathogenic. In this study we reclassified to pathogenic a variant of uncertain significance in LMNA which reduces mRNA expression and leads to cardiac laminopathy. Further investigations are needed to determine the effect on the protein.
Kbtbd13R408C-knockin mouse model reveals impaired relaxation kinetics as novel pathomechanism for NEM6 cardiomyopathy
Authors: Baelde R , Janssen V , Fortes Monteiro A , Galli R , Methawasin M , Granzier H , Kuster D , Van Der Velden J , Ottenheijm C , De Winter J 
Published: May 2024

Abstract
Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): VENI-Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO)
We identified a novel cardiomyopathy gene: KBTBD13 encoding kelch repeat and BTB (POZ) domain containing 13. The Dutch founder variant KBTBD13R408C not only affects skeletal muscle function resulting in nemaline myopathy type 6 (NEM6), but also affects the heart. In the Dutch NEM6 cohort, various cardiac abnormalities were observed, including systolic dysfunction, diastolic dysfunction, atrial fibrillation, ventricular tachycardia and three patients died of sudden cardiac death. The majority of NEM6 patients harbors the Dutch founder variant, c.1222C&gt;T, p.Arg408Cys (KBTBD13R408C). To provide insight in the mechanism underlying cardiac dysfunction in NEM6, here we assessed cardiac structure and function in Kbtbd13R408C-knockin mice, which closely recapitulate the well characterized skeletal muscle phenotype, i.e. impaired relaxation kinetics and mitochondrial dysfunction.
Pressure-volume loop analyses showed that the end-diastolic pressure-volume relation was steeper in Kbtbd13R408C-knockin mice, indicating diastolic dysfunction. Histological evaluation of cardiac structure revealed no increase in fibrosis in Kbtbd13R408C-knockin mice. Also, no alterations in titin isoform composition or myosin heavy chain composition were observed that could account for the increased diastolic stiffness. Next, we studied the contraction and relaxation kinetics in wild type (WT) and Kbtbd13R408C-knockin mice at the intact single cardiomyocyte level by a high-throughput contractility set-up. Our data showed a prolonged relaxation time in Kbtbd13R408C-knockin mice compared to WT mice, indicating impaired relaxation kinetics. No differences in the magnitude of contraction (percentage of shortening) was found between cardiomyocytes of Kbtbd13R408C-knockin and WT mice. In parallel, calcium-handling was assessed by calcium indicator Fura-2AM. These studies reveal that calcium-release is not affected, but calcium-reuptake is slower in Kbtbd13R408C-knockin mice, which might contribute to the impaired relaxation kinetics.
Current studies focus on how KBTBD13R408C affects calcium-reuptake kinetics and sarcomere kinetics in NEM6 cardiomyocytes. Hence, our studies provide the first insights in the pathomechanism underlying cardiac dysfunction in NEM6.