bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clec4e deletion in cardiac resident cells leads to smaller infarct size and better cardiac remodeling following myocardial ischemia-reperfusion injury
Authors: Algoet M , Oosterlinck W , Pusovnik M , Himmelreich U , Gsell W , Veltman D , Gillijns H , Caluwe E , Blazejczyk K , Janssens S 
Published: October 2024

Abstract

Introduction
Clec4e-signalling in cardiac resident cells and circulating immune cells stimulates recruitment of proinflammatory leukocytes to infarcted myocardium following ischemia reperfusion injury (I/R) and contributes to ischemic myocardial damage. Clec4e deletion is associated with reduced cardiac injury and better left ventricular structural and functional remodeling. The mechanisms of this cardioprotective effect remain unknown.
Research question: We investigated whether Clec4e gene function in cardiac resident cells vs infiltrating immune cells mediates cardioprotection during myocardial ischemia-reperfusion injury.

Methods
We generated chimeric mice by performing bone marrow transfer in wild type (WT) C57Bl6/J and C57Bl6/J Clec4e-/- mice. Following total body irradiation using 9.5 Gy in 8w-old WT and Clec4e-/- receptor mice, 5 x 10^6 bone marrow cells originating from Clec4e-/- and WT donor mice, respectively, were injected IV. Four weeks later, mice were anesthetized and subjected to ischemia reperfusion injury (I/R) by transient occlusion of the LAD for 60 min. Troponin levels were measured at 90 min post I/R and 7T-magnetic resonance imaging with late gadolinium enhancement (LGE) for infarct size evaluation was performed at 24 hours and 28 days post I/R without LGE. Mice were euthanized at 28 days post I/R and the heart and long shaft bones were processed for postmortem immunohistochemistry and analysis of BM chimerism.

Results
Immunohistochemical analysis of CLEC4E expression on a bone marrow smear 8 w post bone marrow transfer confirmed successful BM chimerism (7% vs 99%, p&lt;0.01). TnI levels at 90 minutes and LGE assessed infarct size on MRI at 24 hours were not significantly different between groups (n=17 in both groups) (42.1 vs 48.4 ng/ml, and 25.2 vs 31.5% of LVmass in Clec4e-/- mice with WT bone marrow versus in WT mice with Clec4e-/- BM, respectively) suggesting similar myocardial damage . After 28 days, mean LV end diastolic volumes (43µL vs 55µL), and mean end systolic volumes (13µL vs 25µL) were significantly (p&lt;0,05) smaller in Clec4e-/- mice with WT bone marrow resulting in better preserved global LV function (LVEF 62% vs 47%, p&lt;0,05, fig A). Infarct size, semiquantitatively assessed using planimetry on Sirius red stains showed a smaller infarct size in the Clec4e-/- mice with WT bone marrow (6.9% vs 19.8%, p&lt;0.01). Figure B shows a representative example of LGE infarct size to scar tissue on MRI and Sirius red staining.

Conclusion
Clec4e gene deletion in cardiac resident cells, but not in infiltrating hematopoietic immune cells is associated with better functional and structural remodeling after myocardial I/R. Inhibition of Clec4e signaling via blocking antibodies or small molecule inhibitors in cardiac myocytes might be a promising cardioprotective strategy.
The development of small-molecule ERBB4 agonists as a treatment for heart failure
Authors: Cools J , Feyen E , Van Den Bogaert S , Goovaerts B , Fu Y , Wuelfers E , Roderick L , Vandersickel N , De Keulenaer G W , Segers V F M 
Published: October 2024

Abstract
The neuregulin-1 (NRG1)/ERBB4 signaling pathway has emerged as a cardioprotective pathway and is a promising target for the treatment of chronic heart failure. Activation of ERBB4 signaling is known to decrease cardiomyocyte cell death and hypertrophy, and fibroblast collagen synthesis. Recombinant NRG1 (rNRG1) is currently tested in phase III clinical trials for heart failure, but its need for intravenous administration is a disadvantage. In an attempt to circumvent this, we hypothesized that small-molecule-induced activation of ERBB4 is feasible and would recapitulate the effects of its natural ligand on myocytes and fibroblasts.
To this end, we screened 10,240 compounds for their ability to induce homodimerization of ERBB4. We identified a series of 8 similar compounds (named EF-1 – EF-8) that concentration-dependently induced ERBB4 dimerization, with EF-1 being the most potent and effective compound (n = 4-5 independent repeats in each group; Emax = 27.9 ± 4.8% relative to NRG1, EC50 = 10.5 ± 4.5 x 10-6). EF-1 showed neither cytotoxicity nor increased cell proliferation of tumor cell lines. In vitro, EF-1 significantly decreased in a concentration-dependent manner hydrogen peroxide–induced cardiomyocyte cell death (n = 4 independent repeats in each group; P&lt;0.0001 compared to siERBB4, Fig. 1A), angiotensin-II (AngII)-induced cardiomyocyte hypertrophy (n = 20 individual cardiomyocytes in each group; P&lt;0.0001 compared to AngII/vehicle, Fig. 1B), and collagen expression in cultured human fibroblasts (n = 3 independent repeats in each group; P=0.03 compared to siERBB4, Fig. 1C). The observed effects in cultured cardiomyocytes and fibroblasts could be abrogated by siRNA targeting ERBB4, indicating that they were mediated by ERBB4. Moreover, when used in vivo, EF-1 (2 mg/kg/day) significantly decreased AngII-induced left ventricular Col1a1 and Col3a1 mRNA expression (n = 4-5 mice in each group; P=0.02 and P=0.004 compared to AngII/vehicle, respectively) and inhibited AngII-induced myocardial total and interstitial fibrosis in wild-type mice (n = 4-5 mice in each group, Fig. 2), but not in Erbb4-null mice. Moreover, EF-1 decreased acute cardiotoxicity (assessed by troponin release) in wild-type mice treated with doxorubicin (DOX; n = 8-9 mice in each group; P&lt;0.0001 compared to DOX/vehicle), but not in Erbb4-null mice.
In conclusion, we show that small-molecule-induced ERBB4 dimerization and activation is feasible, and recapitulates anti-fibrotic and cardiomyocyte protective effects in the heart in an ERBB4-dependent manner, both in vitro and in vivo. This could be the start for the further development of small-molecule ERBB4 agonists as a novel class of drugs to treat heart failure. Cardiomyocyte-protective effect in vitroAnti-fibrotic effect in vivo
Direct in vivo cardiac reprogramming with circular RNA of single transcription factor delivered by fibroblast-targeting lipid nanoparticles
Authors: Wang Q Z , Wang Z M , Huang Z Y , Ge J B 
Published: October 2024

Abstract

Background
Adult mammalian cardiomyocytes (CMs) hold limited capacity for self-regeneration, thus leading to permanent loss of functional myocardium once suffering from injury, especially myocardial infarction (MI). Therefore, cardiac regeneration therapy has been regarded as a potential path to help restore damaged tissue. Direct cardiac reprogramming is one of the most promising ways to boost cardiac regeneration as it could convert resident cardiac fibroblasts into functional induced cardiomyocytes (iCMs). However, difficulty of delivery has been one of the biggest problems that hinder the further clinical translation of this technique such as concerns of mostly used retrovirus vectors and lack of fibroblast-specific targeting ability. In our previous research, we have found that after knocking down of Ybx1 gene, single transcriptional factor Tbx5 could induce cardiac reprogramming of fibroblasts without adding traditional Mef2c and Gata4. But whether this cocktail could achieve in vivo direct cardiac reprogramming still remains to be explored.

Objective
We planned to develop fibroblast-targeting lipid nanoparticles (LNP) to delivery circular RNA(circRNA) of Tbx5 and small interfering RNA(siRNA) of Ybx1 to realize in vivo cardiac reprogramming in a mouse model of myocardial infarction.

Results
We first screened different formulations of tdTomato mRNA delivered-LNP both in primary neonatal cardiac fibroblasts and in the myocardial infarction model and found that formulation XF4d could realize specific selectively uptake by cardiac fibroblasts instead of cardiomyocytes. Then we succeeded in synthesizing XF4d LNP delivering Tbx5 circRNA and Ybx1 siRNA (LNPXF4d@Tbx5+siYbx1) and validated its stability at 4°C. Next, after infecting LNPXF4d@Tbx5+siYbx1, primary neonatal CFs and mouse embryonic fibroblasts could be reprogrammed into functional iCMs. We further measured the protein expression of Tbx5 and Ybx1 in CFs after LNPXF4d@Tbx5+siYbx1 treatment. What’s more, we used fibroblast-specific lineage tracing mice (Fsp1Cre/tdTomato mice) to prove the successful conversion of resident CFs into iCMs in the mouse model of myocardial infarction by intramyocardial injection of LNPXF4d@Tbx5+siYbx1. At last, we found that LNPXF4d@Tbx5+siYbx1 could help improve cardiac function after injury and reduce fibrosis, as measured by echocardiography and Masson’s trichrome staining.

Conclusion
We suggest that our fibroblast specific LNPs delivering single transcriptional factors could a promising method to realize in vivo cardiac reprogramming and help treat myocardial injury, with high possibility of clinical translation and less biosafety concerns.Graphical Abstract
Upregulation of the sodium potassium pump current supresses ectopic activity after stem cell delivery in the human-based heart after myocardial infarction
Authors: Riebel L , Wang Z , Martinez-Navarro H , Dasi A , Trovato C , Rodriguez B 
Published: October 2024

Abstract

Background
Cell therapy is being explored to restore the damaged and intrinsically irreparable human heart. Whilst preclinical studies showed improvements in cardiac function after injury, they also highlighted a critical pro-arrhythmic window when delivered cells produce ectopy-induced ventricular tachycardia. Recent experiments investigating the cells in vivo maturation suggested upregulation of the inward rectifier potassium current (IK1) and knock-out of the funny current (If) and sodium calcium exchanger (INaCa) to supress the arrhythmias[1].

Purpose
Whilst promising, such modifications may impact the cells’ calcium dynamics and ultimately, their efficacy. The goal of this study is to identify novel ionic targets that improve therapy safety whilst maintaining efficacy by employing the unique predictive capabilities of modelling and simulation.

Methods
For this, we used our established modelling and simulation framework of cell therapy in the chronically infarcted human heart with Purkinje, validated against experimental and clinical data from the action potential to the ECG. We incorporated experimentally observed gene expression of in vivo cell maturation[1] into our framework to reproduce human pluripotent stem cell-induced cardiomyocyte (hPSC-CM) electrophysiology at day 0 and day 14 after injection. To consider variability amongst experimentally reported hPSC-CMs, we also created a fast-beating hPSC-CM model by upregulating the SERCA pump current, If and INaCa.

Results
Our results showed that while day 0 hPSC-CMs did not cause spontaneous activity, day 14 hPSC-CMs produced ectopic beats in the ventricles every 1.5s. The rapid beating hPSC-CM phenotype at day 14 elicited tachycardia through spontaneous beating and intermittent re-entrant wavefronts (see Figure 1). Next, we demonstrated 65% upregulation of the sodium-potassium pump current (INaK) together with a 50% increase in IK1 and knock-out of If as a novel pathway to quiescence. Importantly, our simulations highlighted that compared to INaCa knock-out, an increase in INaK allowed for physiological calcium transients.

Conclusion
To conclude, in this work we have utilised modelling and simulation of the injured human heart to 1) capture pre-clinically observed arrhythmias after cell therapy and 2) identify INaK upregulation as a novel target to mitigate safety concerns, whilst preserving efficacy.
Exploration of vitamin D hydroxy metabolites C3 epimers in cardiovascular patients: comparative cross-sectional study
Authors: Abouzid M , Kruszyna L , Kagan L , Glowka F , Mikulska A A , Filipowicz D , Karazniewicz-Lada M 
Published: October 2024

Abstract

Background
Research on vitamin D deficiency has recently surged in popularity. This issue has been acknowledged as a widespread problem, often called a "pandemic", and approximately 90% of the Polish population suffers from vitamin D deficiency. The 3-epi-25(OH)D2 and 3-epi-25(OH)D3 metabolites are stereoisomers of 25(OH)D2 and 25(OH)D3 metabolites, and they may be accidentally measured when determining 25(OH)D levels and result in overestimating metabolite concentrations.

Purpose
Our study aims to identify vitamin D hydroxy metabolites (25-hydroxyvitamin D2, 25-hydroxyvitamin D3, and their epimers 3-epi-25-hydroxyvitamin D2 and 3-epi-25-hydroxyvitamin D3) in patients with cardiovascular disease and healthy volunteers. To our knowledge, no similar studies have been conducted on this topic.

Method
We included 27 adult patients with venous thrombosis (fourteen males and thirteen females, aged 64.11±14.84 years) and 35 healthy volunteers (thirty-three females and two males, aged 36.37±12.29 years). We used our validated UPLC-MS/MS method to measure the concentrations of 25(OH)D2, 25(OH)D3, 3-epi-25(OH)D2, and 3-epi-25(OH)D3. Statistica 13.3 with Plus Kit 3.0 was used for the statistical assessment. Normal variables were represented as mean and standard deviation, and non-normal variables as the median and interquartile range. A P-value &lt; 0.05 was considered statistically significant for all tests.

Results
Patients had significantly lower levels of epi-25(OH)D2 than the healthy control group (0.6 [0.4] ng/mL vs. 2.2 [1.3-4.3] ng/mL, p = 0.004). Similarly, they exhibited significantly lower levels of %epi-25(OH)D2 (8.6 [6-22.3] % vs. 39.4 [18.5] %, p = 0.035). Females had higher levels of 25(OH)D3 than males (26.5 [16.2-37.9] ng/mL vs. 18.8 [7.5] ng/mL, p = 0.04). They also exhibited higher levels of total 25(OH)D3 (30.3 [15.6] ng/mL vs. 19.4 [7.8] ng/mL, p = 0.016). Higher age (OR 1.12, 95% CI 1.07 to 1.18), being male (OR 17.77, 95% CI 3.54 to 89.3), and lower % 3-epi-25(OH)D2 (OR 0.92, 95% CI 0.84 to 0.998) were univariate predictors for patients with venous thrombosis.
Conclusion: Demographic factors within a given population may affect the 25(OH)D3 concentration. The results indicate that vitamin D epimeric metabolites, particularly epi-25(OH)D2, and their percentage were different in patients compared to healthy volunteers. Additional studies involving a larger population are necessary to fully comprehend the relationship between these vitamin D epimeric metabolites and cardiovascular health
The BET inhibitor Apabetalone protects against heart failure with preserved ejection fraction by suppressing myocardial inflammation
Authors: Costantino S , Gorica E , Mohammed S A , Telesca M , Mongelli A , Herwig M , Ambrosini S , Ruschitzka F , Hamdani N , Paneni F 
Published: October 2024

Abstract

Background
Posttranslational histone modifications, play a major role in cardiac hypertrophy and dysfunction. Apabetalone (APA), a selective inhibitor of bromodomain and extraterminal containing protein family (BET) proteins, prevents bromodomain-containing protein 4 (BRD4) interactions with chromatin thus modulating transcriptional programs in different organs.

Purpose
We sought to investigate whether APA could be beneficial in cardiometabolic heart failure with preserved ejection fraction (cHFpEF).

Methods
Mice were subjected to high fat diet feeding and L-NAME treatment for 15 weeks to induce cHFpEF. Histology, mouse echocardiography (Vevo3100) and Treadmill exhaustion test were performed. Unbiased gene expression profiling by PCR array and proteomics analysis (Olink) was employed in left ventricular (LV) myocardial specimens from HFpEF mice and control animals. Cultured cardiomyocytes (CMs) treated with palmitic acid (PA) were used as an in vitro model of metabolic stress. cHFpEF mice were chronically treated with the BET inhibitor APA (150mg/kg/day) or vehicle (DMSO). In order to translate our findings to the human setting, passive stiffness of skinned CMs collected from cHFpEF patients was assessed before and after APA treatment.

Results
HFpEF mice displayed LV hypertrophy, diastolic dysfunction, myocardial fibrosis, lung congestion and impaired exercise tolerance as compared to controls. Interestingly, diastolic dysfunction - assessed by E/A ratio and isovolumic relaxation time (IVRT) - and lung congestion were significantly reduced in HFpEF mice treated with APA, while exercise tolerance was improved. Transcriptomic analysis in PA-treated CMs and LV mouse specimens from cHFpEF mice showed a profound deregulation of genes controlling inflammation, namely IL-6, TNF-alpha, and IL-1beta. ChIP assays showed BRD4 occupancy on the promoter of several inflammatory genes, including IL6. Treatment with APA suppressed most of inflammatory genes, with a pronounced effect on IL6 expression. Moreover, APA reduced circulating levels of several inflammatory chemokines. The beneficial effects of APA were explained by modulation of IL-6/CaMKII/STAT3 pathway both in cHFpEF hearts and PA-treated CMs. In skinned CMs from cHFpEF patients, both APA and IL6 blockade were able to attenuate passive stiffness.

Conclusions
Our findings set the stage for preclinical studies and exploratory clinical trials testing APA in patients with cHFpEF.
The ghrelin receptor agonist AC01 improves cardiac function in non-human primates and in mice with heart failure by increasing cardiomyocyte contractility
Authors: Pironti G , Hage C , Carlstrom M , Champeroux P , Stahlberg M , Stromberg P , Lovati E , Andersson D C , Lund L H 
Published: October 2024

Abstract

Background
Current therapy for Heart Failure (HF) includes neurohormonal antagonist and modulator drugs that improve remodelling, symptoms and clinical outcomes. However, these drugs do not target the underlying problem of reduced contractility. Improving cardiac contractility without harmful consequences is an unmet need in heart failure therapy. The human peptide hormone ghrelin increases cardiac output in HF patients and increases contractility in murine cardiomyocytes.

Purpose
We aim to study the cardiovascular effects of a novel oral small molecule ghrelin receptor agonist, AC01, in in vivo and ex vivo mouse models and in non-human primates.

Methods
HF mice (N=11) underwent pressure-volume loops analysis of cardiac functional and hemodynamic to assess the effects of intravenous AC01 (N=7) or placebo (N=4). Primary cardiomyocytes isolated from HF (N=3) and SHAM (N=5) mice, were treated with combinations of vehicle, AC01, ghrelin receptor antagonist (D-Lys-3-GHRP-6) and pertussis toxin (PTX, a Gαi signalling inhibitor). Live cell imaging was performed to assess cardiomyocyte fractional shortening and Ca2+ signalling, while biochemistry assays were employed to measure PKA activity, and phosphorylation of cardiac Troponin I (cTnI). Cynomolgus monkeys (N=6) were instrumented with devices to measure pulse contour, central aortic blood pressure and ECG devices. Cardiovascular effects of AC01 following single oral dosing were assessed through pulse contour hemodynamic modelling and analysis of autonomic system activation.

Results
In HF mice, AC01 significantly improved cardiac output (p&lt; 0.01), stroke volume (p&lt; 0.001), and ejection fraction (p&lt; 0.001), and increased nominally the end-systolic pressure-volume curve relationship. In cardiomyocytes, AC01 dose-dependently improved fractional shortening (p&lt; 0.01) without increasing Ca2+ transient amplitudes. AC01 reduced PKA activity (p&lt; 0.05) and reduced phosphorylation of cTnI at Serine 23-24 (p&lt; 0.01). These effects were blocked by pre-treatment with either D-Lys-3-GHRP-6 or PTX. In monkeys, oral AC01 sustainably increased cardiac output (p&lt; 0.05) and stroke volume (p&lt; 0.05) and reduced heart rate without altering central systolic blood pressure or causing tachycardia or arrhythmia.

Conclusions
AC01 improved CO, SV, and EF in HF mice by increasing contractility in a load-independent fashion. AC01 increased cardiomyocyte contractility without affecting Ca2+ transient amplitudes, through ghrelin receptor Gαi signalling, leading to reduced phosphorylation of cTnI. AC01 improved left ventricle systolic function in monkeys. AC01 is a first in class novel inotrope, which improves contractility in different species without harmful mobilization of Ca2+. AC01 should be explored for the treatment of patients with heart failure.graphical abstract
CD14 blockade preserves left ventricular structure and systolic function in a murine model of ST-elevation myocardial infarction
Authors: Donner D G , D'elia A A , Bloom J , Kiriazis H , Wright D K , Tham Y K , Abbate A , Lavine K , Crowe D , Redlich G , Ziegelaar B W , Mcmullen J R , Wang B H , Kaye D M 
Published: October 2024

Abstract

Background
Cluster of differentiation-14 (CD14) facilitates the excessive pro-inflammatory monocyte-macrophage response to myocardial injury. Both acute and chronic infiltration of pro-inflammatory macrophages are implicated in the immunological progression of ischemic heart failure. However, investigation of clinically practicable strategies of CD14 blockade are yet to be reported.

Purpose
This fully blinded and randomised preclinical study evaluated the efficacy of a neutralising anti-CD14 antibody given at reperfusion in a murine model of reperfused ST-elevation myocardial infarction (STEMI) with key clinical features.

Methods
Large anterior STEMI was induced in 48 adult mice by left anterior descending coronary artery occlusion for 1 h prior to reperfusion and randomisation to receive anti-CD14 antibody, isotype control (IgG2a) or saline weekly for four weeks (independently blinded). Outcome measures included functional assessments by 9.4T cardiac magnetic resonance (CMR) imaging and ultra-high-resolution echocardiography at 21- and 28-days post-STEMI, respectively.

Results
Multi-plane short axis CMR at 21-days post-STEMI revealed greater left ventricular (LV) ejection fraction in the anti-CD14 antibody-treated group compared with saline- and isotype-treated controls (30±1 vs 19±1 and 20±1 %, respectively, p&lt;0.001; Figure 1A). CMR also revealed reduced LV dilatation with anti-CD14-treatment compared to control groups (76±5 vs 102±8 and 107±7 µl EDV in saline- and isotype-treated controls, respectively, p&lt;0.05). Parasternal long axis echocardiography at 28 days post-STEMI confirmed that anti-CD14 antibody treatment was associated with greater LV systolic function compared to saline and isotype controls (30±1 vs 24±1 and 25±2 % EF, respectively, p&lt;0.05; Figure 1B). Preservation of LV end-diastolic (86±4 vs 111±6 and 101±5 µl, p&lt;0.01) and end-systolic (61±3 vs 84±5 and 77±5 µl, p&lt;0.01) volumes was also observed with anti-CD14 treatment. Global longitudinal strain (GLS) of the LV was also significantly greater at 28 days post-STEMI with anti-CD14 treatment relative to saline and isotype controls (-8.5±0.4 vs -6.8±0.3 and -6.6±0.4 %, respectively, p&lt;0.05).

Conclusion(s)
The findings of this fully blinded and randomised preclinical study provide evidence of a clinically practicable strategy of CD14 blockade initiated at reperfusion to mitigate progressive LV systolic dysfunction and dilatation post-STEMI.Figure 1.Functional outcome measures