bluuebunny/crossref_metadata_2025_split huggingface dataset:
Secretomes from human epicardial adipocytes modulate atrial lymphatics and atrial fibrosis
Authors: Takahashi M , Abe I , Harada T , Yamasaki H , Takano M , Kondo H , Teshima Y , Miyamoto S , Takahashi N 
Published: October 2024

Abstract

Background
Cardiac lymphatics maintains myocardial fluid and immune cell homeostasis. Downregulation of cardiac lymphatics leads to cardiac dysfunction through impairment of inflammation and edema. On the other hand, it is well known that adipose tissue accumulation causes lymphatic dysfunction and impairs lymphedema.

Purpose
We evaluated the expression of atrial lymphatics in human left atrial appendage (LAA) histologically and biologically. Subsequently, we examined secretomes from epicardial adipose tissue (EAT)-derived adipocytes and validated if they change atrial lymphatics expression using ex vivo Organo-culture system.

Methods
Human LAA samples were collected from forty-two patients during cardiovascular surgery. They were categorized into the sinus rhythm (SR) group (n=16, 73.1±10.4 years), the paroxysmal AF (PAF) group (n=13, 69.8±12.6 years) and the persistent AF (PeAF) group (n=13, 71.2±6.5 years).
Human EAT were also excised from patients with and without AF (SR; n=5, AF; n=11) during cardiovascular surgery. Preadipocytes were extracted from EAT by homogenization and collagenase treatment, and cultured to confluence. After differentiation and maturation to adipocytes, cell culture supernatant (CCS) was collected, and was dropped onto the epicardial side of left atrial tissues excised from 8 weeks old male rats for 7 days using an ex vivo organo-culture system.

Results
In human LAA samples, mRNA expression of lymphangiogenesis-related genes (LYVE1, PROX1, VEGFC, and VEGFR3) was significantly lower in the PeAF group compared to the SR group (p=0.0370, &lt;0.0001, 0.0157, and 0.0009). The number of LYVE1-positive atrial lymphatic endothelial cells (LECs) was also significantly lower in the PeAF group compared to the SR group and the PAF group (p=0.0186 and 0.038). There was a negative correlation between the number of LYVE1-positive atrial LECs and the area percentage of atrial myocardial fibrosis (r=-0.5350, p&lt;0.001).
In the experiment using organo-culture system, lymphangiogenesis-related genes expression (Lyve1, Prox1, Vegfc, and Vegfr3) of rat atria treated with CCS of adipocytes from AF patients was significantly lower than those from SR patients (p=0.0391, 0.0100, 0.0034, and 0.0338). Furthermore, the CCS of adipocytes from AF patients contained higher protein levels of leptin, which is known to suppress lymphangiogenesis (p=0.0357). Leptin treatment (100ng/ml) on rat atria also decreased lymphangiogenesis-related genes expression such as Lyve1, Prox1, Vegfc, and Vegfr3 (p=0.0413, &lt; 0.0001, &lt;0.0001, and 0.0190).

Conclusions
Our study with human LAA demonstrated that atrial lymphatics interact with atrial myocardial fibrosis/progression of AF. Furthermore, our findings indicate that secretomes from EAT-derived adipocytes regulate atrial lymphatics expression, and leptin plays an important role in modulating atrial lymphangiogenesis.
Identification of genetic variants associated with exercise-induced atrial fibrillation in high-performing racehorses
Authors: Mattingsdal M , Nath L C , Sorensen E , Nissen S D , Fintl C , Tveit A , Aaronaes M , Myrstad M , Buhl R , Franklin S H , Christophersen I E 
Published: October 2024

Abstract

Background
Atrial fibrillation (AF) is the most common cardiac arrhythmia in athletes. Despite a lower burden of classical cardiovascular risk factors, the prevalence of AF in athletes is comparable to that in the general population of similar age (~13%, mean age 65.5), suggesting that exercise-induced AF may have different underlying mechanisms. The prevalence of AF in thoroughbred (TB) and standardbred (STB) racehorses is also relatively high (~5%), suggesting exercise as an independent risk factor. Due to selective breeding and complete control of pedigrees, racehorses are well-suited for genetic studies. Common and rare genetic variation explain a substantial part of AF variance, but no study has identified genetic variants associated with exercise-induced AF in any species.

Objective
In this project, we aimed to use the racehorse as a model to identify genetic variants associated with exercise-induced AF, and in a future study, possibly replicate the results in human athletes. Here we present preliminary results from the genome-wide association study (GWAS) of AF in racehorses.

Methods
We collected blood or hair samples from 181 STB and TB racehorses in which 71 had paroxysmal or persistent AF verified by ECG. We extracted DNA and performed whole-genome genotyping using a commercial equine genotyping platform (670k markers). We phased and imputed un-genotyped markers and increased the sample size of the control group, using publicly available equine data from similar breeds from the European Nucleotide Archive. We conducted a GWAS of 7.85 million markers in 71 cases and 296 controls using PLINK2 with covariates adjusted for population stratification, batch and sex.

Results
We identified one significant locus downstream of the protocadherin gene PCDH18 associated with AF in racehorses. The same locus has been associated with the ECG-trait P-wave terminal force in humans. Changes in P-wave terminal force is associated with increased atrial size, delayed interatrial conduction, left ventricular fibrosis and left atrial function, and considered a good predictor of AF occurrence. Several non-significant but interesting signals were also identified including the genes SLC6A15 (amino acid transport), MYBPH (myosin binding), MYF6 and MYOG (myoblast differentiation).

Conclusion
In these preliminary results, we have identified a new genetic locus associated with AF in racehorses. In addition, we have identified several candidate genes for further studies to elucidate the genetic background of exercise-induced AF. We aim to replicate our findings in a population of human athletes. Our results may aid the development of risk prediction tools for exercise-induced AF and new drugs for tailored treatment of AF in general.
Engineering hiPSC-derived tissue models for advanced amyloidosis research and therapy development
Authors: Montero Calle M , Anaut Lusar I , Larequi E , Coppiello G , Aranguren X , Salterain N , Garcia De Yebenes M , Prosper F , Gavira J J , Mazo Vega M M , Iglesias Garcia O 
Published: October 2024

Abstract

Introduction
Transthyretin (TTR) amyloid cardiomyopathy (ATTR-CM) is a life-threatening disease currently lacking an optimal therapy, stemming from the absence of representative models. Our work aims to stablish for the first time an all-human 3D model of ATTR-CM where the main cellular and extracellular players of the pathology are present.

Methodology
A human induced pluripotent stem cell (hiPSC) line was derived from a patient carrying a p.Ser43Asn TTR mutation and differentiated into hepatocytes (hiPSC-HEPs), cardiomyocytes (hiPSC-CMs) and cardiac fibroblasts (hiPSC-CFs). Cells were embedded in a hydrogel (tailored for each cell type) and combined with a designed 3D printed scaffold using Melt Electro Writing (MEW) technology. Tissues were maintained in culture for up to 4 weeks and characterized by staining, albumin production, electrophysiological, plus genomic analysis. Exposure to TTR fibrils (TTR-FIB) was evaluated.

Results
Human hepatic and cardiac functional tissues can be generated using MEW-designs. These constructs exhibited albumin production and an active spontaneous contraction, respectively. Moreover, tissues displayed well distributed cells throughout the 3D-structure, positive for specific hepatic and cardiac mature markers. Interestingly, electrophysiological analysis showed that cardiac tissues displayed shortened calcium transients after TTR-FIB exposure compared to unexposed tissues. However, no differences were found in terms of beat rate, metabolic activity and gene expression for the concentrations used.

Conclusion
We have developed an advanced model of ATTR-CM capable of recapitulating the multisystem complexity of the disease, which will contribute to advancing our understanding of the mechanisms of the disease, and help discovering and formulating new treatments.
Genome-wide association analysis reveals insights into the molecular etiology of dilated cardiomyopathy
Authors: Zheng S , Henry A , Consortium H E R M E S , Ware J S , Lumbers R T 
Published: October 2024

Abstract

Introduction
Dilated cardiomyopathy (DCM) is a primary heart muscle disease characterized by ventricular dilatation and impaired contractility. While considered a Mendelian disorder, recent evidence highlights the important role of common genetic variation. Better characterization of the genetic architecture will provide opportunities for improved diagnosis, risk stratification and biological understanding.

Methods
We performed a GWAS meta-analysis of 14,256 DCM cases and 1,185,671 controls of European ancestry from 16 studies (GWASDCM). To improve discovery power, we performed multi-trait analysis of GWAS (GWASMTAG) with three genetically correlated and clinically relevant cardiac imaging traits in 36,203 individuals. To identify effector genes at loci, we used a two-step approach: 1) the nearest gene and top 3 genes prioritized by PoPS or V2G were selected as candidates; and 2) totality of evidence including 5 additional methods (coding variant, co-localization with expression, TWAS, ABC-model, and known Mendelian cardiomyopathy genes) was summarized in a single score. We performed rare variant burden analysis (MAF&lt;0.1%) for predicted truncating variants (PTV) in established DCM-causing genes to highlight DCM genetic architecture, and in prioritized GWAS genes, against DCM and quantitative CMR traits in UK Biobank (UKB) and 100,000 Genomes Project (GeL), implemented by REGENIE. A polygenic score (PGS) generated using a Bayesian framework (PRS-CS) was assessed for association with the same outcomes in UKB participants, including among PTV carriers in established DCM-causing genes.

Results
We identified 80 independent loci, of which 65 were novel (62 loci in GWASDCM, and 54 loci in GWASMTAG) (Figure 1A). High-confidence genes were prioritized at 62 loci, including in genes with established roles in Mendelian cardiomyopathies (TTN, BAG3, FLNC, MYBPC3, FHOD3, ALPK3), and were enriched in key biological processes (Figure 1B). We characterized DCM genetic architecture across the allelic spectrum (Figure 2A). Rare variant burden analysis highlighted novel associations with DCM and quantitative traits for PTVs in NEDD4L and MAP3K7 in UKB that were replicated in GeL (Figure 2B). PGS was associated with DCM and quantitative CMR traits (OR per PGS SD 1.8, P&lt;1x10-16) (Figure 2C). Individuals in the top centile had 4-fold increased risk of having DCM compared with median risk. PGS stratified penetrance of rare variants in 1,546 carriers of pathogenic variants (top quintile 7.3%, bottom quintile 1.7%, P 0.005).

Conclusion
We have performed the largest DCM GWAS, resulting in 80 significant loci (65 novel), and prioritized genes using a systematic approach. We identify novel DCM-causing genes (NEDD4L and MAP3K7) and generate a PGS that associates with DCM and modulates penetrance in carriers of Mendelian disease-causing rare variants.Figure 1Figure 2
Disparities in the access to atrial fibrillation ablation in Denmark
Authors: Zoerner C R , Toennesen J , Riis-Vestergaard L D , Middelfart C , Hein R , Rasmussen P V , Ruwald M H , Gislason G H , Hansen M L 
Published: October 2024

Abstract

Background
Atrial fibrillation (AF) is a common arrhythmia that can lead to serious complications such as stroke, heart failure, as well as reduced quality of life. Radiofrequency and cryoablation are safe and effective treatments for AF, but they are not offered equally to all patients.

Purpose
The study aims to identify the demographic groups more or less likely to undergo AF ablation.

Methods
Using nationwide National Registries, all Danish patients with newly diagnosed AF between the 1st of January 2005, and the 31st of December 2018 were identified. The association between patients, stratified by gender, age, level of education and attachment to the job market, and the likelihood of receiving AF ablation was investigated using multivariable Cox proportional-hazard analysis. Cumulative incidence of AF ablation among these groups was calculated using the Aalen-Johansen estimator, taking death as a competing risk into account.

Results
A total of 176,248 patients were included in the study. Men were more likely to receive ablation than women (7% vs 3%). When analysing age, patients aged 25-44 and 45-64 were most likely to receive ablation, while only 0.7% of patients aged 80 or above received ablation. The rate of ablation significantly decreased with decreasing level of education. Patients with a Ph.D. or doctorate degree were more likely to receive ablation than patients with only basic school education (22% vs 2%). Finally full-time employed patients were most likely to receive ablation, followed by self-employed, unemployed, on sick leave, undergoing education, and early retired patients. Retired patients were the least likely to receive ablation (3%).

Conclusion
This study found that women, older patients, patients with lower levels of education, and patients who are not employed or who are retired are less likely to receive AF ablation. These findings suggest that there are significant social and economic disparities in AF ablation treatment in Denmark.Ablation by educationForest plot: Cox analysis
Remodeling of adult rat heart subjected to pressure overload from the neonatal period is dependent on the sex
Authors: Olejnickova V , Zabrodska E , Hrdlicka J , Holzerova K , Peskova M , Papousek F , Kvasilova A , Sedmera D 
Published: October 2024

Abstract

Background
Congenital heart diseases (CHD) represents the most common birth defect. Despite progress in their treatment improving acute survival, there is a paucity of data concerning the long-term consequences of CHD in adults.

Purpose
Here, we investigate the remodeling in adult rat hearts subjected to pressure overload from the early postnatal period.

Methods
We used the neonatal abdominal aortic constriction (AAC) model to analyze morphological, functional (by echocardiography), and electrophysiological long-term outcomes. Given the known differences in cardiac pathologies between males (M) and females (F), we focused on the role of sex in cardiac remodeling.

Results
Our data showed that both sexes exhibited a similar left ventricular weight/body weight ratio at the age of 12 weeks, indicating comparable left ventricle (LV) enlargement as a response to AAC (increase by 103 ± 9 % in M AAC and 99 ± 10 % in F AAC vs. sham-operated animals). However, the right ventricular weight/body weight and lung/ body weight ratios, indicative of LV failing, differed significantly between sexes with better values in F AAC. The favorable cardiac remodeling in F AAC was corroborated by significantly smaller LV systolic and diastolic diameters, along with a lower amount of myocardial fibrosis. Using optical mapping, we revealed preserved longitudinal and transversal conduction velocities (CVL; CVT) in females (CVL 104 ± 8 vs. 109 ± 8 cm/s and CVT 66 ± 7 vs. 59 ± 6 cm/s in F AAC and F Sham, respectively). However, compared to M Sham, the conduction velocities in M AAC showed a significant decrease (CVL 80 ± 3 vs. 92 ± 3 cm/s and CVT 35 ± 2 vs. 54 ± 3 cm/s). Similarly, the amount of connexion 43 (Cx43) and its phosphorylated state (Cx43Ser368) was preserved in F AAC while exhibiting a decrease in M AAC compared to the sham-operated controls. Thus, electrophysiological findings implicate that while the adult M AAC underwent pro-arrhythmogenic remodeling due to the elevated workload, the adult F AAC preserved physiological conduction properties.

Conclusion
Our data showed different consequences of the increased pressure load exposed from early after birth to the adult M and F heart. These findings highlighted the involvement of both sexes in cardiac studies.
Human coronary blood single-cell sequencing combined with exosome proteomic profiling reveals the molecular mechanism of recurrent in-stent restenosis (R-ISR)
Authors: Jiang Y , Miao Y 
Published: October 2024

Abstract

Background
Percutaneous coronary intervention (PCI) is recognized as the core treatment for symptomatic myocardial ischemia and acute coronary syndrome (ACS). However, the complex pathogenesis of recurrent in-stent restenosis (R-ISR) after stent implantation is still insufﬁciently understood.

Purpose
This study reports the first single-cell RNA sequencing and proteomic profiling to characterize pathogenesis of R-ISR in humans.

Methods
To reveal the pathophysiology and molecular mechanism of R-ISR, we performed single-cell RNA sequencing to identify RISR-induced changes in transcriptional landscape in coronary blood mononuclear cell composition. Besides, proteomic profiling of human coronary plasma-derived exosomes was used to further screen different proteins. Transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and western blot analysis were performed to identify exosomes. In vitro cell biology experiments were used to validate the discoveries of bioinformatics analysis.

Results
Compared with normal subjects, the percentage of FCGR3B high monocytes, memory T cells and plasmacytoid dendritic cells (DCs) was increased in R-ISR. Furthermore, we observed a marked increase in the expression of JUN, FOS, CXCL8, S100A8 enriched in the IL-17 signaling pathway that is known to play a crucial role in activating inflammation, mediating immune response, and even maintaining inflammation to chronicity. According to in vitro experiments, the co-cultured system demonstrated that FCGR3B high monocytes isolated from RISR patients activated the expression of inflammatory factors in endothelial cells (ECs), such as IL-1β, IL-6 and TNF-α. Inflammatory activated endothelial cells could release a large amount of exosomes, proteomic profiling of exosomes isolated from ECs observed a significant upregulation of MYLK expression, which could promote proliferation and migration of vascular smooth muscle cells (VSMCs) by activating VEGFR-2 signaling pathway.

Conclusions
Our study reveals a novel subset of FCGR3B high monocytes in R-ISR patients that could activate ECs inflammation via IL-17 signaling pathway. Activated ECs release exosomes rich in MYLK, which promote proliferation and migration of VSMCs, ultimately leading to repeated restenosis.
MicroRNA-145-5p restricts cardiac scar resolution during cardiac regeneration
Authors: Wang H , Perttunen S , Immonen K , Narumanchi S , Hagerstrom I , Kalervo K , Paavola J , Laine M , Tikkanen I , Lakkisto P 
Published: October 2024

Abstract

Background
Human hearts have a very limited capacity to renew cardiomyocytes following injury. The lost myocardium is permanently replaced with noncontractile fibrotic tissue, consequently leading to heart failure. In contrast, zebrafish retain cardiac regenerative capacity during their lifetime. After injury, zebrafish hearts undergo transient fibrotic scarring that subsequently resolves and is replaced with new cardiomyocytes over time. Thus, understanding the molecular mechanisms governing cardiac scar resolution in zebrafish could offer insights into enhancing the regenerative capacities of human hearts.

Objective
We aimed to decipher the molecular pathways associated with zebrafish cardiac scar resolution.

Methods
We investigated the mRNA and miRNA responses to injury at 14 days post-injury by high-throughput transcriptome profiling of RNAs isolated from healthy or cryoinjured hearts. The prediction of miRNA-mRNA interactions was performed to identify the most differentially expressed miRNAs and their target genes. These miRNAs and genes were validated in zebrafish regenerating hearts and in the left ventricles of ischemic cardiomyopathy or dilated cardiomyopathy patients. The potential role of identified miRNAs in cardiac scar resolution was investigated in human cardiac fibroblasts.

Results
Principal component analyses identify two distinct clusters in both the mRNAome and miRNAome corresponding to healthy and injured hearts, indicating significant changes in transcriptome profiles during zebrafish cardiac regeneration. Gene set enrichment analyses indicate that molecular pathways involved in extracellular matrix organization and inflammatory response are markedly activated whereas genes associated with mitochondrial organization and oxidative phosphorylation are downregulated in injured hearts. We observed the downregulation of miR-145-5p and the upregulation of procollagen V in the injured hearts. In contrast to zebrafish, in the left ventricles of ischemic cardiomyopathy patients, miR-145-5p is significantly upregulated and procollagen V α1 is downregulated. Theoretical prediction of miRNA-mRNA interactions indicates procollagen V α1 is negatively correlated with miR-145-5p. Overexpression of miR-145-5p in human cardiac fibroblasts downregulates collagen V α1 and alpha smooth muscle actin, upregulates procollagen I and matrix metalloproteinase 9, and inhibits cell proliferation and migration. In contrast, inhibition of miR-145-5p upregulates collagen V α1 and alpha smooth muscle actin, downregulates procollagen I and matrix metalloproteinase 9, and stimulates cell proliferation and migration.

Conclusion
Our study suggests that miR-145-5p may play a role in the suppression of myofibroblast transdifferentiation via collagen V α1, which restricts scar resolution and cardiac repair.
Clinical implications of atrial fibrillation recurrence vs. burden following catheter ablation: outcome data from 3 contemporary clinical trials using an insertable cardiac monitor
Authors: Goldenberg I , Huang D T , Aktas M , Steinberg J , Mcnitt S , Polonsky S , Zareba W 
Published: October 2024

Abstract

Background
Recurrence of atrial fibrillation (AF) following catheter ablation is typically defined in clinical trials in a binary fashion, e.g. &gt; 30 seconds or none. However, the clinical implications of this endpoint, adopted from formal guidelines, have been questioned.

Purpose
We hypothesized that assessment of AF burden can provide incremental clinical and management implications to the dichotomous definition of AF recurrence following ablation.

Methods
The study population comprised 147 patients enrolled in 3 ongoing multicenter randomized clinical trials (ICM REDUCE-AF [N=67]); HYBRID-AF (N=55] and DAPA-AF [N=25]), each employing an insertable cardiac monitor (ICM) to assess post-ablation AF recurrence and burden. The rate of cardiovascular (CV)-related healthcare utilization (CV-HCU, defined as the total number CV admissions, ED visits, cardioversions, procedures, and unplanned office visits) was compared based on AF recurrence (defined as &gt;2 minutes of ICM-detected AF) vs. based on AF burden post-ablation (defined as time in AF divided by total monitoring time).

Results
Among the 147 study patients, mean age was 65 years; 53 (36%) were women; and 78 (53%) had persistent AF. At 12-months post-ablation (excluding blanking), the cumulative probability of AF recurrence was 60% (Figure 1A). However, 27% of AF recurrences were associated with a very low AF burden (≤0.1%) and low CV-HCU (10 events per 100 patient-months), similar to patients without AF recurrence (11 events per 100 patient-months). In contrast, recurrences with a higher AF burden (&gt;0.1%; mean 17% ± 25%) were associated with a 3-fold higher rate of CV-HCU (31 events per 100 patient-months, p&lt;0.001; Figure 1B). Findings were consistent regardless of AF-type, comorbidities or LVEF.

Conclusions
A substantial proportion of AF recurrences following contemporary AF ablation are associated with a very low AF burden without apparent effect on CV outcomes, whereas higher AF burden is associated with increased CV-HCU. These findings stress the need to move beyond a dichotomous definition of AF recurrence and to monitor AF burden post-ablation to guide management decisions in contemporary clinical practice.Figure 1