bluuebunny/crossref_metadata_2025_split huggingface dataset:
Semaglutide modulates adipogenic differentiation and extracellular acidification in epicardial (EAT) and subcutaneous (SAT) adipose tissue stromal cells from patients with cardiovascular disease
Authors: Basdas R , Sanchez-Lopez D , Nunez Caamano J R , Al-Rubaye S , Fu X , Martinez-Cereijo J M , Fernandez A L , Reija L , Gonzalez-Juanatey J R , Eiras S 
Published: October 2024

Abstract

Backround
Cardiovascular disease (CVD) is the main cause of death in the world. One of the known risk factors is the epicardial fat (EAT) accumulation, which is around the myocardium and coronaries playing a paracrine role over them. Although mature and functional adipocytes are involved in energy balance and glucose metabolism, the hypertrophic state increases the production of fatty acid binding protein 4 (FABP4), which is a pro-inflammatory adipokine, with consequences on extracellular acidification. Recent data shows that glucagon-like peptide receptor agonists 1 (GLP1ra) drug improves the insulin response and reduces EAT thickness. Although GLP1ra has a direct effect on hypothalamus for reducing food intake, this drug might play a direct role on adipogenesis process in this fat stromal cells.

Purpose
Our study aims to demonstrate the effect of semaglutide on adipogenesis and metabolism in epicardial and subcutaneous stromal cells from patients with cardiovascular disease.

Methods
The study was approved by the Galician Research Ethics Committee, and subcutaneous adipose tissue (SAT) and EAT samples from 17 patients were obtained undergoing open-heart surgery with informed consent. Stromal cells from biopsies were isolated and cultured. Adipogenesis was induced for 15 days with or without 1 nM semaglutide, given by Novo-Nordisk (Bagsværd, Denmark), using an adipogenesis cocktail. Cells were lysed and RNA was isolated for RT-qPCR. Target genes were amplified for Glucagon like peptide 1- receptor (GLP1R), differentiation, adipogenesis, glucose metabolism and cellular markers. Extracellular acidification rate was measured with glycolytic rate assay on Seahorse. Lipids accumulation was tested by AdipoRed staining.

Results
Stromal cells from both tissues express GLP1R but higher differentiation factor (PGC1α) was detected in SAT compared to EAT (p=0.02), as well as adipogenesis induction. After semaglutide treatment, we observed a downregulation of FABP4 and GLUT1 in EAT (p=0.01 and p=0.02, respectively). Despite FABP4 was not modulated on SAT, there was a reduction of PGC1α levels. (p=0.02). Since glitazones upregulate PGC1α, which is used for adipogenesis induction, these results might suggest the counteract mechanism of semaglutide. The metabolism assay showed that semaglutide reduces extracellular acidification rate in EAT cells (p=0.04) and oxidative glycolysis with semaglutide treatment (p=0.003) but not in SAT cells.

Conclusions
Semaglutide reduces adipogenesis, through modulation of PGC1α transcription factor in EAT from patients with cardiovascular disease and extracellular acidification and oxidative glycolysis. These results might help to understand one of the mechanisms associated with EAT reduction in patients with semaglutide treatment.
Skeletal myocyte-specific knockout of Ptpn1 and Ptpn2 enhances inflammatory response in muscle and increases mortality in polymicrobial sepsis
Authors: Brinschwitz B , Wulfert C , Stein V , Kappert K , Fielitz J 
Published: October 2024

Abstract

Background
Critically ill patients often suffer from heart and skeletal muscle atrophy and failure (intensive care unit acquired weakness; ICUAW). Inflammation and sepsis are major risk factors for ICUAW. Critically ill patients with sepsis frequently develop insulin resistance that decreases protein synthesis and increases protein degradation in muscle eventually leading to ICUAW. The link between inflammation and insulin resistance is not well understood, but protein tyrosine phosphatases (PTP), that inhibit insulin signaling via insulin receptor (INSR) dephosphorylation as well as inflammation-associated pathways, are implicated.
Hypothesis: We hypothesized that PTP1B and TC-PTP mediate inflammation-induced insulin resistance and muscle atrophy in heart and skeletal muscle.

Methods and Results
qRT-PCR analyses showed that the proinflammatory cytokines tumor necrosis factor (TNF), interleukin (IL)-1β, and IL-6 caused a ~2-fold increase in Ptpn1/PTP1B and Ptpn2/TC-PTP mRNA expression in C2C12 myocytes as well as in neonatal rat ventricular cardiomyocytes. Inhibition of the IL-6/GP130 pathway by siRNA and inhibitors in myocytes in vitro and skeletal muscle specific gp130 knockout mice in vivo attenuated IL-6-induced Ptpn1/PTP1B and Ptpn2/TC-PTP mRNA expression. CLP-induced polymicrobial sepsis was associated with a significant increase in gene expression and protein content of pro-inflammatory cytokines (Tnf, Il1b, Ifng) and leukocyte markers (CD68, CD11c, F4/80) in muscle of skeletal myocyte specific double knockout (Ptpn1+Ptpn2loxP/loxP, MCK cre, dKO) compared to wildtype (Ptpn1+Ptpn2loxP/loxP) mice in sepsis. This also resulted in a lower survival rate of dKO mice in sepsis (42% WT vs. 23% dKO). Immunohistological analyses revealed centralized nuclei, macrophage/monocyte infiltration and enhanced regeneration (Myh3, Pax7, Ki67) in tibialis anterior muscle of septic dKO mice. A strong activation of the NLRP3-inflammasome, as indicated by cleavage of caspase 1, GSDMD, GSDME and caspase 8, indicative for a pronounced inflammation and activated cell death pathways was observed in muscle of septic dKO mice.

Conclusion
The proinflammatory cytokine IL-6 increases the expression of Ptpn1 and Ptpn2 and enhances overall PTP activity. Selective inhibition of the IL-6R/GP130 signaling pathway by JAK2- and STAT3-inhibition as well as Gp130 deletion in myocytes in vivo attenuates those effects. Muscle-specific deletion of Ptpn1 and Ptpn2 in skeletal muscle leads to increased mortality, enhanced pro-inflammatory response and induced inflammatory, programmed cell death pathways in sepsis. Our data show that Ptpn1 and Ptpn2 play a key anti-inflammatory role in skeletal muscle.
Human macrophages are immunnoprofiled by pericardial fluid small extracellular vesicles modulating lipid metabolism mechanisms
Authors: Ben-Aicha S , Anwar A , Martino F , Kyriazis P , Sattler S , Punjabi P , Emanueli C 
Published: October 2024

Abstract

Background
Coronary artery disease (CAD) is the main cause of myocardial infarction and consequent ischemic heart disease (IHD). Macrophages are central to CAD. Small extracellular vesicles (sEVs) can shuttle microRNAs and other molecular cargos from cell to cell, mediating response in target cells. Recent evidence supports the sEVs role in modulating macrophage phenotype. The pericardial fluid (PF) contains sEVs and immune cells including cavity-like macrophages.

Purpose
This study investigates whether PF-sEVs regulate macrophages, contributing to a specific immunophenotype in CAD patients.

Methods
PF was collected from CAD patients undergoing coronary bypass surgery (CABG) and non-atherosclerotic patients operated for mitral valve repair (control group). sEVs were isolated and characterised for size (Nanosight tracking analysi), tetrasapanin content (Nanoview chips) and microRNA content (RNA seq analysis). Monocytes from healthy donors were isolated from buffy coats and differentiated into macrophages following established protocols. Macrophages were incubated with either CAD-sEVs or non-CAD sEVs for 24h at 37oC. The cells were collected and processed for mRNA analyses (qRT-PCR) and flow cytometry. Further bioinformatics were employed to understand functional pathways targeted by PF-sEVs-miRNA.

Results
In line with the human-PF macrophages profile, exposure to CAD-sEVs reduces the anti-inflammatory profile of human macrophages. CAD-sEVs treated macrophages showed a CCR2-, CD36+low, CD206+low profile. While non-CAD-sEVs did not statistically differ from PBS nor untouched groups, CAD-sEVs increased the mRNA level of IL1a, IL1b, TNFa and decreased MRC1. Bioinformatic analysis showed that 861 miRNAs were decreased in the PF-sEVs from CAD patients compared to non-CAD. miRNA targets prediction and pathway analyses reported that clusters of PF-miRNAs could regulate CD36, decreased in PF-macrophages.

Conclusions
We demonstrate, that sEVs isolated from PF-CAD reduce the anti-inflammatory profile of human macrophages, and target crucial lipid metabolism pathways. These clinically relevant results could drive to decipher improved therapeutics to modulate the epicardial/myocardial immune response in CAD patients.
Synthetic torpor confers cardioprotection against myocardial ischaemia/reperfusion injury in the rat
Authors: Ali Khan M , Taddei L , Elley M , Wilcox R , Pickering A , Ambler M 
Published: October 2024

Abstract

Introduction
Torpor is a hypothermic, bradycardic, hypometabolic state enabling animals, such as mice, to survive in unfavourable environmental conditions such as cold exposure or reduced food availability. It is thought to be a cardioprotective state. There is interest in developing models that mimic aspects of torpor in clinical settings such as ischaemia-reperfusion injury. The preoptic area of the hypothalamus (POA) has emerged as a key centre for triggering torpor in the mouse.

Purpose
Induce a synthetic torpor-like state in a species that does not naturally enter torpor (the rat) by chemoactivation of neurons in the POA that correspond to those that induce torpor in the mouse. Test the cardioprotective effects of synthetic torpor in the Langendorff ischaemia-reperfusion preparation.

Methods
Designer receptors exclusively activated by designer drugs (DREADDs) were used to exogenously activate excitatory neurons in the POA of the rat hypothalamus. Viral vectors (pAAV-CaMKIIa-hM3D(Gq)-mCherry) were stereotaxically injected bilaterally into the POA under ketamine and medetomidine anaesthesia, resulting in expression of DREADDs in excitatory neurons. Control animals received a vector delivering the gene for a fluorescent protein only. DREADD receptors in transfected neurons were activated by subsequent injection of Clozapine-N-Oxide (CNO, 2mg/kg IP), which results in neuronal activation and induces synthetic torpor. Heart rate and core temperature were monitored using implanted telemeters. 2 weeks after vector injection, animals were anaesthetised using 5% isoflurane and culled by cervical dislocation. Hearts were excised and ex-vivo whole heart perfusion at 37°C was performed using the Langendorff apparatus. Hearts were subjected to 30 minutes of global warm ischaemia followed by 60 minutes of reperfusion. Hearts were stained using tetrazolium triphenyl chloride, and infarct size as a proportion of the total heart area calculated.

Results
Chemoactivation of rat POA neurons induced synthetic torpor characterised by bradycardia (pre: 341.0 ± 17.73bpm, post: 233.4 ± 20.47bpm, paired t (4) = 5.4791, p = .0054) and hypothermia (36.2 ±0.40°C vs 31.6 ± 0.55°C (paired t (4) = 7.9023, p = .0014). CNO had no effect on heart rate or core temperature in control animals. The mean infarct size was significantly lower in synthetic torpor (21.54 ±2.84%) compared to control hearts (29.62 ±2.59%) (unpaired t (23) = 2.1054, p = .0464).

Conclusions
Synthetic torpor, induced centrally in a species for which torpor is not a natural behaviour, confers striking cardioprotection in an ex-vivo ischaemia-reperfusion model. This novel approach to cardioprotection against myocardial ischaemia/reperfusion injury should be further investigated as a potential therapeutic target for use in clinical practice.
The impedance drop early after energy delivery predicts steam pops during radiofrequency ablation
Authors: Takahashi S , Mine T , Miki T , Nakai M , Yoshikawa F , Takai K , Takada M , Fujita K , Nishibori M , Maruyama T , Ishihara M 
Published: October 2024

Abstract

Background
Steam pops during radiofrequency ablation (RFA) can cause serious complications. However, predictive factors for steam pops remain unclear.

Purpose
To investigate predictors for steam pops.

Methods
An in vitro experiment was performed using fresh bovine left ventricular myocardium. A myocardium cut into 4-5 cm slabs was fixed at the bottom of a constant temperature bath with temperature adjusted to 36.5 degrees Celsius, and a non-pulsatile flow rate of 5 L/min was generated. Using the catheter with a laser-cut 8Fr4.0mm flexible tip, RFA was applied at 30W, 60 seconds, perpendicular catheter placement to the tissue at various contact forces (5, 10, 20, 30, 40, 50g). A total of 138 lesions were created by applying RFA 23 times at each setting. Lesion depth and width were measured after RFA.

Results
Steam pops were observed in 49 of 138 lesions (36%). The higher impedance decrease in the first 5 seconds (-21.0±11.0Ω vs. -7.6±8.5Ω, P&lt;0.0001), the larger impedance drop from initial to minimum impedance (if steam pop occurred, minimum impedance before steam pop was applied) (-28.9±13.0Ω vs. -13.1±12.9Ω, P&lt;0.0001), higher initial impedance (132±48Ω vs. 87±38Ω, P&lt;0.0001), power regulation by temperature control (44.9% vs 4.5%, P&lt;0.0001), higher contact force (31.2±14.9g vs. 22.9±15.9g, P=0.0030), larger LSI (6.8±2.1 vs. 7.5±1.8, P=0.0037) were associated with steam pops. In multivariate analysis, the high impedance drops in the first 5 seconds (OR 2.0 for each 5Ω increase, 95%CI 1.0-1.3; P=0.033) and the power regulation by temperature control (OR 7.3, 95%CI 2.2-29.9; P=0.001) were independently related. In ROC curve analysis of the impedance drops in the first 5 seconds, an optimal cut-off value of steam pops was 8.0Ω (AUC 0.85, sensitivity 88%, specificity 73%) (figure 1). Steam pops were predicted with a sensitivity of 45% and specificity of 97% using both the impedance drop ≥ 8.0Ω in the first 5 seconds and power regulation by temperature control. Lesion depth and width were associated with total impedance reduction in lesions with an impedance drop &lt; 8.0Ω during the first 5 seconds (R²=0.14, P=0.0012 with depth, R²=0.21, P&lt;0.0001 with width), while were not associated with in lesions with an impedance drop ≥ 8.0Ω (figure 2).

Conclusion
The impedance drop early after RF energy delivery may predict steam pops during RFA.
Protective role of Metrnl on macrophage recruitment during the acute inflammatory phase in a mouse model of myocardial infarction
Authors: Ferrer-Curriu G , Soler-Botija C , Monguio-Tortajada M , Poblador F , Navarro Gascon A , Blasco Roset A , Villarroya F , Galvez-Monton C , Roura S , Bayes-Genis A , Planavila A 
Published: October 2024

Abstract

Introduction
Meteorin-like protein (Metrnl) is a cytokine involved in the attenuation of inflammation. Previously, a cardioprotective role of Metrnl against cardiac hypertrophy and ischemia/reperfusion has been described. After myocardial infarction (MI), macrophages recruited from the spleen, and their capacity to shift from inflammatory (M1) to reparative (M2) phases determines the fate of cardiac repair.

Purpose
The aim of this study was to analyse the function of Metrnl in a mouse model of permanent MI during the acute inflammatory phase.

Methods
Wild-type (WT), Metrnl Knock-out (Metrnl-/-) and Metrnl-reconstituted Metrnl-/- mice (AAV9-Metrnl, with myocardial-specific tropism) were subjected to MI by coronary artery ligation. After 4 days, cardiac function was assessed using echocardiography at baseline and 4 days post-MI. Monocyte populations were analysed in spleen and blood by flow cytometry, and macrophages infiltrating the infarcted myocardium by gene expression analyses.

Results
Echocardiographic analysis demonstrated that Metrnl deficiency led to cardiac dysfunction (FAC p=0.02) accompanied by myocardial dilation 4 days post-MI (EDV p=0.02; ESV p=0.01). On the contrary, the overexpression of Metrnl in the myocardium of AVV9-Metrnl mice restored cardiac function compared to Metrnl-/- group (FAC p=0.01, EDV p=0.04, ESV p=0.09). Furthermore, we observed a reduction in splenic monocytes (CD11b+F4/80+) in Metrnl-/- mice compared to the WT group at 4 days post-MI (p=0.06). In particular, a significant decrease in pro-inflammatory Ly6CHigh and CD86+ monocytes was noted in the spleens of Metrnl-/- mice compared to the WT group (p=0.03; p=0.04 respectively), suggesting their mobilization out of the spleen, but not in the AVV9-Metrnl group. Although the total number of Ly6CHigh and Ly6CLow monocytes in the bloodstream was similar in all groups, there was a trend to different expression in the CCR2 and CCR5 chemokine receptors (p=0.07; p=0.06 respectively). At the same time, M1 macrophage recruitment chemokines (CCL2) and inflammatory markers (TNFα) were significantly induced in the ischemic area of the infarcted myocardium compared to the remote zone in the WT and Metrnl-/- groups (CCL2 p=0.03; p=0.01 respectively; TNFα p=0.008;p=0.04 respectively). In contrast, TNFα and CCL2 genes were not induced in the ischemic area of AVV9-Metrnl mice. Regarding M2 macrophages, the Arg1 marker was significantly reduced in the ischemic zone of Metrnl-/- mice compared to the WT group (p= 0.01), while in the AVV9-Metrnl group was recovered (p= 0.04).

Conclusions
Our results demonstrate that the absence of Metrnl promotes the recruitment of inflammatory macrophages to the ischemic myocardium and is associated to cardiac dysfunction.
Developing endoscopic cell sheet delivery device using a beating human heart simulator and a pig model for minimally invasive cardiac regenerative therapy
Authors: Hori Y , Yamashita H , Murata K , Kuroda Y , Iida J , Hakamada K , Minatoya K , Masumoto H 
Published: October 2024

Abstract

Introduction
Recently, clinical trials have commenced for cardiac regenerative therapy utilizing stem cells in patients with heart failure. Among the various transplantation approaches, there is a growing demand for less invasive methods to transplant sheet/patch-shaped cell products onto the heart surface, rather than resorting to conventional open surgery. This is particularly important considering the need for immunosuppressants due to allogeneic cell transplantation.

Objective
This study aims to develop a device for endoscopic transplantation of cell sheets onto the beating heart surface.

Methods
Prototype devices, initially developed in our prior study using a static heart model (Regenerative Therapy, 2020), were refined to better suit the cell sheet transplantation procedure onto a beating heart. We constructed a three-dimensional (3D) model of a beating heart located inside a thoracic cavity model, based on human computed tomography data and a 3D printer dedicated to simulating endoscopic surgical procedures. Human mesenchymal stromal cell (MSC)-derived cell sheets were prepared using temperature-responsive culture dishes and transferred onto a beating heart model pulsating at 80 beats per minute. We assessed the technical feasibility (N=8). Furthermore, skeletal muscle tissue was harvested from the thigh of the Clawn miniature pigs, and skeletal myoblasts were cultured from enzymatically digested tissue to create a cell sheet for autologous transplantation (8.0×10⁶ cells/sheet). Subsequently, the cell sheets labeled with Hoechst 33342 were endoscopically transplanted onto the pig heart surface (N=2). The pigs were sacrificed one week later, and the engraftment of the cell sheet was histologically evaluated.

Results
Successful deployment of MSC sheets onto the beating heart model was achieved in all procedures with one trial (100% success rate). The procedure duration from device insertion to the completion of cell sheet transplantation averaged 142±19 seconds. In experiments on autologous transplantation of myoblast cell sheets, two cases were successfully accomplished, with the transplanted cell sheet positive for Hoechst 33342 observed on the heart surface.

Conclusion
We have developed an endoscopic cell sheet delivery device using a pulsating heart model and a pig model, which holds promise for minimally invasive cardiac regenerative therapy in the future. Further investigations into the safety of the procedure are warranted for the clinical application of this system.
Cardiac secreted-HSP90alpha in cardiomyocyte hypertrophy by N-Cadherin mediated signaling under pressure overload
Authors: Pan L , Huang C X , Jin X J , Lin J Y , Wang Y , Li J X , Wang X , Zhang L , Zhang G P , Dong H M , Dai Y X , Zou Y Z , Gong H 
Published: October 2024

Abstract

Background
Left ventricular hypertrophy (LVH) in response to pressure overload is strongly associated with adverse cardiovascular outcomes. Heat shock protein 90 (HSP90) has been reported to be involved in cardiac remodeling under stress.

Aims
Here, we evaluate whether serum HSP90α (an isoform of HSP90) increases and associates with cardiac hypertrophy in patients with hypertension or severe aortic stenosis (AS), and explore the potential mechanisms in experimental pressure overload mouse model.

Methods
Serum HSP90α levels in patients with hypertension or aortic stenosis (AS) were determined by ELISA. Pressure overload mouse model was built by a transverse aortic constriction (TAC). Cardiac function was assessed by echocardiography. Cardiac hypertrophy was examined by histology, western blot and RNA analysis.

Results
Serum levels of HSP90α were higher in patients with hypertension or AS than in the control group, respectively, and the levels positively correlated with LVH. HSP90α levels also increased in heart tissues of patients with obstructive hypertrophic cardiomyopathy (HCM), and mice after TAC, in parallel with the hypertrophic markers. TAC induced the enhanced expression and secretion of HSP90α from cardiomyocytes and cardiac fibroblasts. Knockdown of HSP90α or blockade of extracellular HSP90α (eHSP90α) prevent the development of LVH under pressure overload in vivo and in vitro. By Nano-HPLC-MS/MS analysis, we identified eHSP90α interacted with N-cadherin in cardiomyocyte surface, which induced the activation of β-catenin and promoted β-catenin to bind TCF7 (a member of TCF/Lef family) in nucleus, enhanced the transcription of hypertrophic genes, contributing to cardiac hypertrophy and dysfunction under pressure overload.

Conclusions
Our data demonstrated that cardiac secreted-HSP90α promoted myocardial hypertrophy by N-Cadherin mediated β-catenin/TCF7 signaling under pressure overload. It indicates the therapeutic potential of targeting HSP90α-initiated signaling against cardiac hypertrophy and dysfunction under pressure overload.