tbuckley/cabot-search huggingface dataset:
Sex differences in cardiac ferroptosis after acute myocardial infarction in wild type and aryl hydrocarbon receptor knockout mice
Authors: C Delgado, R Fedichkina, L Martin-Nunes, M J Piedras, V Ramiro-Ponce, C Alvarez-Lucena, M Gil-Fernandez, M Fernandez-Velasco, L Bosca
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): MICIN/Agencia Estatal de Investigación (DOI: 10.13039/50110001103) (NextGeneration, EU/PRTR) Background and Purpose Ferroptosis is a new regulated programmed cell death pathway, driven by iron-dependent phospholipid peroxidation, that plays an important role in the development of cardiovascular diseases. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor of the basic Helix-Loop-Helix-PER-ARNT-SIM superfamily. Upon ligand binding, AhR translocates into the nucleus and dimerizes with the AhR nuclear translocator; the heterodimer then binds to dioxin-response elements located in the promoter region of receptor-regulated genes, most of which are involved in xenobiotic metabolism. Beyond its role in metabolizing exogenous toxins as part of an adaptive chemical response, it is well known that AhR is activated by endogenous ligands and it has been postulated that AhR has important functions in physiological and/or pathological conditions. Here we studied sex differences in cardiac ferroptosis after acute myocardial infarction (AMI) in mice and the implication of defective AhR signalling on this process. Methods and Results AMI was induced in 8–10-weeks-old males and females AhR+/+ and AhR-/- mice by ligation of the left anterior descending coronary artery. Animal care and experimental procedures followed the principles of animal care (NIH publication Nº85-23 revised 1985) and the guidelines for ethical care of experimental animals of the European Union (2010/63/EU). Survival analysis showed that 16% of AhR+/+male mice and 14% of AhR+/+ female mice died 72 h after AMI surgery whereas the mortality was 100% in AhR-/-male mice and only 17% in AhR-/- female mice group. The treatment of AhR-/- AMI male mice with ferrostatin (1 mg/kg i.p) increased survival to 40%. Immunofluorescence analysis of cardiac staining levels of 8-hydroxy-2’-deoxyguanosine revealed higher oxidative stress in AhR+/+AMI male mice compared with AhR+/+AMI females, 24 h after surgery. The absence of AhR in AMI males showed an increased oxidative stress that was similar to that obtained in AMI AhR+/+ males but significantly greater than that observed in AhR-/- AMI females. Finally, analysis of differential expressions of classical genes related to ferroptosis in AhR-/- AMI male and AMI female mice, 24 h after surgery, showed, only in males, a reduced expression of ferritin heavy chain 1 and ferroportin, and an increased expression of phospholipase A2. Conclusion Our results show that loss of AhR in males but not in females favours the ferroptosis process associated with myocardial ischemia, highlighting a possible role for this nuclear receptor in cardiac remodelling and survival after AMI.
Whole-blood transcriptome unveils altered immune response in acute myocardial infarction patients with aortic valve sclerosis
Authors: P Poggio, L Piacentini, V A Myasoedova, M Chiesa, C Vavassori, D Moschetta, V Valerio, G Giovanetti, I Massaiu, N Cosentino, G Marenzi, G I Colombo
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): Fondazione Umberto Veronesi (Research Grant 2011-12 to GIC) Fondazione Gigi e Pupa Ferrari ONLUS (FPF-14 to PP) Background Aortic valve sclerosis (AVSc) presents similar pathogenetic mechanisms to coronary artery disease (CAD) and is associated with short- and long-term mortality in CAD patients. Evidence of AVSc-specific pathophysiological traits in acute myocardial infarction (AMI) is currently lacking. Purpose We aimed to identify a blood-based transcriptional signature that could differentiate AVSc from non-AVSc patients during AMI. Methods Whole-blood transcriptome of AVSc (n = 44) and no-AVSc (n = 66) patients with AMI was assessed by RNA-sequencing on hospital admission. Feature selection, differential expression, and enrichment analyses were performed to identify gene expression patterns discriminating AVSc from no-AVSc and infer functional associations. Multivariable Cox regression analysis was used to estimate the hazard ratios of cardiovascular events in AVSc versus no-AVSc patients. Results This cross-sectional study identified a panel of 100 informative genes capable of distinguishing AVSc from no-AVSc patients with 94% accuracy. Further analysis revealed significant mean differences in 143 genes, of which 30 genes withstood correction for age and previous AMI or coronary interventions. Functional inference unveiled a significant association between AVSc and key biological processes, including acute inflammatory responses, type I interferons (IFN) response, platelet activation, and hemostasis. Notably, AMI patients with AVSc exhibited a significantly higher incidence of adverse cardiovascular events during a 10-year follow-up period, with a full adjusted hazard ratio of 2.4 (95% CI: 1.3–4.5). Conclusions Our findings shed light on the molecular mechanisms underlying AVSc and provide potential prognostic insights for AMI patients with AVSc. During AMI, AVSc patients showed increased type I IFN response and earlier adverse cardiovascular outcomes. Novel pharmacological therapies aiming at limiting type I IFN response during or immediately after AMI might improve poor cardiovascular outcomes of AMI patients with AVSc.
A novel DSP zebrafish model reveals training- and drug-induced modulation of arrhythmogenic cardiomyopathy phenotypes
Authors: R Celeghin, G Risato, G Beffagna, M Cason, M Bueno Marinas, M Della Barbera, N Facchinello, R Branas Casas, S Rizzo, L Dalla Valle, F Argenton, G Thiene, N Tiso, K Pilichou, C Basso
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Associazione Italiana per la Ricerca sul Cancro [AIRC grant IG-2017-19928], Italian Ministry of University and Research [grant PRIN 20173ZWACS] Introduction Arrhythmogenic cardiomyopathy (AC) is an inherited disorder characterized by progressive loss of the ventricular myocardium causing life-threatening ventricular arrhythmias, syncope and sudden cardiac death in young and athletes. About 40% of AC cases carry one or more mutations in genes encoding for desmosomal proteins, including Desmoplakin (Dsp). Methods We generated the first stable Dsp knock-out (KO) zebrafish line able to model cardiac alterations and cell signalling dysregulation, characteristic of the AC disease. Results Our stable Dsp knock-out (KO) zebrafish line was characterized by cardiac alterations, edema and bradycardia at larval stages. Histological analysis of mutated adult hearts showed reduced contractile structures and abnormal shape of the ventricle, with thinning of the myocardial layer, vessels dilation and presence of adipocytes within the myocardium. Moreover, TEM analysis revealed "pale", disorganized and delocalized desmosomes. Intensive physical training protocol caused a global worsening of the cardiac phenotype, accelerating the progression of the disease. Of note, we detected a decrease of Wnt/β-catenin signalling, recently associated with AC pathogenesis, as well as Hippo/YAP-TAZ and TGF-β pathway dysregulation. Pharmacological treatment of mutated larvae with SB216763, a Wnt/β-catenin agonist, rescued pathway expression and cardiac abnormalities, stabilizing the heart rhythm. Conclusion Our Dsp KO zebrafish line recapitulates many AC features observed in human patients, pointing at zebrafish as a suitable system for in vivo analysis of environmental modulators, such as the physical exercise, and the screening of pathway-targeted drugs, especially related to the Wnt/β-catenin signalling cascade.
Modulation of mitochondrial dynamism in kupffer cells impacts systemic metabolism
Authors: F Fantini, L Da Dalt, A Moregola, G B Vingiani, M Svecla, O Terenghi, J Nour, R Bellini, F Bonacina, G D Norata
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): University of Milan Background Kupffer Cells (KC) are hepatic resident macrophages that are essential for liver physiology and contribute to the development of Non-Alcoholic Fatty Liver Disease (NAFLD). The liver of patients with NAFLD shows different expression of some key regulators of inner mitochondrial membrane fusion compared with healthy subjects, including OPA1 protein, which is a mitochondrial protein whose activity promotes mitochondrial fusion and positive modulation of oxidative phosphorylation. Aim Given that Kupffer Cells have both immune and metabolic roles, their mitochondria are critical for their and energy requirements and their functionality. This project aims to study how the inhibition of OPA1-driven mitochondrial fusion affects immune-metabolic response and progression of NAFLD by exploring the role of OPA1 in both a Standard and High-fat diet context. Methods mice selectively lacking OPA1 in Kupffer Cells were fed with either a Standard diet or a High-fat diet for 20 weeks. The metabolic phenotype was assessed by in vivo indirect calorimetry, measurement of plasma and tissue lipid profile, glucose and insulin sensitivity assays, and complete immunophenotype characterization. Single cell RNA sequencing was also performed to profile with higher resolution the impact of OPA1 deficiency on Kupffer Cell function and cross talk with other liver cells types within the hepatic niche. Results Under Standard diet conditions mice selectively lacking OPA1 in Kupffer Cells show a significant reduction in the KC1 pro-inflammatory subset, while the pro-resolutive KC2 increases significantly. In addition, mice lacking OPA1 in KCs show a metabolic preference towards carbohydrates, despite comparable energy expenditure, O2 consumption and CO2 production. The systemic immune profile was comparable between the two groups, with an expected reduction in KC total number under High-fat diet conditions, where no significant differences were observed between the two groups in plasma cholesterol and triglyceride levels, while a significant reduction in liver fibrosis was observed with liver histology. Conclusions Taken together these preliminary data suggest that OPA1-mediated inhibition of mitochondrial fusion in Kupffer Cells affects the systemic metabolic response under Standard diet with a reflection also on High-fat diet conditions, where systemic metabolism is comparable between the two groups, but the loss of OPA1 appears to influence the progression of NAFLD through a reduction in total liver fibrosis. Ongoing studies aim to understand the molecular mechanisms underlying these different immune-metabolic responses.
Exploring PD-1+ and tissue resident memory T cells in atherosclerotic diseases
Authors: K Van Dijk, A De Jong, P H A Quax, M R De Vries
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): Health Holland Visual Sonics Background Checkpoint inhibitor therapy (ICI), a potent oncologic treatment, has been associated with an enhanced risk for atherosclerotic cardiovascular events and increased plaque progression. Among the key players affected by ICI are tissue resident memory T cells (Trm), a subset residing in tissues and characterized by CD44, CD69, PD-1, and CD103. Although Trms have been associated with chronic inflammatory conditions, their role in atherosclerosis and accelerated atherosclerosis, as observed in postinterventional diseases such as vein graft disease, remains elusive Here, we present an investigation into the role of PD-1 positive cells and Trms in accelerated atherosclerosis as found in vein graft disease. Methods Human carotid atherosclerotic plaques were stained with a MOVAT stain and scored to determine plaque stability. 25 Stable and 25 unstable plaques were stained for CD3+ T cells and PD-1. Hypercholesterolemic ApoE3*Leiden mice underwent vein bypass surgery and were sacrificed at t7, t14, t28 (n=6 per time point). The vein grafts were processed for flow cytometry to quantify the Trms population, using markers including CD4+, CD8+, CD44+, CD25-, CD69+, CD103+ and PD-1+. Hypercholesterolemic ApoE3*Leiden mice underwent vein bypass surgery. Biweekly, mice received ICI (anti-PD-L1) or control antibody (n=7). After 28 days vein graft morphology was assed using MOVAT staining and vein graft inflammation by staining MAC3 and CXCL10. Results Within human atherosclerotic plaques, PD-1-expressing T cells were predominantly located in the shoulder regions of the necrotic core. Unstable lesions exhibited significantly higher levels of PD-1 expressing CD3+ T cells compared to stable lesions (p=0.001). Furthermore, the percentage of PD-1 expression positively correlated with immune cell infiltration scores (p=0.019). In murine vein grafts, Trms were identified through flow cytometry. A trend was observed indicating an increase in the number of CD4 and CD8 Trms at t14 compared to t7 Trms (CD8+, CD44+, CD69+/CD103+). At t28, the number of CD4 and CD8 Trms decreased compared to t14, with PD1+ expressing Trms showing a similar trend, peaking at t14. Vein grafts in mice receiving anti-PD-L1 mAb showed no morphological differences compared to the control group. However, a significant difference in inflammation was noted in the anti-PD-L1 treated group, characterized by a higher number of macrophages (p=0.02) and increased expression of CXCL10 (p=0.008). Conclusion Here we demonstrate the association of PD-1+ T cells with unstable lesions and reveals that Trms increase during the inflammatory phase and decrease during the stabilizing phase of accelerated atherosclerosis. Trms emerge as potential detrimental targets of ICI therapy, which is characterized by increased inflammation.
Impact of immune system humanization on atherosclerosis in dyslipidemic immunocompromised mice
Authors: F Bonacina, A Moreola, J Nour, S Greco, G B Vingiani, G D Norata
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Cariplo Foundation. PRIN (Italian Ministry of University and Research) Background and aim Given the key role of immune response during atherosclerosis and the therapeutic interest on biologics targeting human immune cells, the need of experimental models to translate molecular mechanisms and test therapeutic approaches for atherosclerosis is continuously increasing. Here we provide an immune and metabolic characterization of an innovative immunodeficient mouse humanized with human hematopoietic cells on an atheroprone background. Methods LDLR-KO mice were crossed with the immunodeficient C57BL/6J strain Rag2-KO/IL2rg-KO/CD47-KO (TKO, IMSR_JAX:025730) to generate an immunocompromised dyslipidemic mouse (TKO-LDLR KO mice) recipient of human hematopoietic stem cells (hCD34+). Results TKO-LDLR KO were first characterized for their immune and metabolic profile. TKO mice are deficient in mature lymphocytes and NK cells and this profile was conserved in TKO-LDLR KO mice. Under high cholesterol diet, TKO-LDLR KO present monocytosis with increased levels of Ly6Chi monocytes compared to TKO-LDLR KO at standard diet, develop marked dyslipidemia, steatosis and atherosclerosis. This profile confirms the suitability of TKO-LDLR KO mice for atherosclerosis studies. Next we tested the impact of immune system humanization on atherosclerosis. TKO-LDLR KO pups received a low-dose irradiation (200 cGy) and thereafter 2 x 10^5 hCD34+ were injected in the liver. Engraftment of human leukocytes (hCD45+) was evaluated after two months by flow cytometry analysis from tail blood. This approach allows to reconstitute between 10-30% of hCD45+, mainly B and T cells. The humanization with hCD34+ cells worsens atherosclerosis development as compared to non-humanized TKO-LDLR KO mice. Conclusion We have generated and characterized the humanized dyslipidemic TKO-LDLR KO mouse. This mouse model presents human B and T cells and represents and important toll to investigate the impact of human adaptive immune cell pharmacological modulation in the context of atherosclerosis.
In vivo calcium and voltage mapping of the zebrafish heart
Authors: D Schepers, E Sieliwonczyck, B Vandendriessche, C Claes, J Bastianen, I Pintelon, W De Vos, D Snyders, M Alaerts, J Huisken, B Loeys
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Research Foundation Flanders (FWO) Purpose Inherited cardiac arrhythmias are characterized by a disturbance in the normal electrical functioning of the heart due to a dysfunction of cardiac ion channels, accessory proteins and/or structural components. This complex process is difficult to model in vitro, while in vivo mouse models differ substantially from humans with regards to cardiac electrophysiology. Thus, there is a need for alternative disease models in cardiac arrhythmia research. The zebrafish heart shows remarkable similarity to humans in its electrocardiogram and action potential (AP) morphology. Due to the optical translucency of zebrafish larvae, it is possible visualize the cardiac calcium and voltage dynamics across their entire hearts in vivo by use of genetically encoded calcium and voltage indicators (GECI and GEVI). We combined the fast kinetics of a next generation voltage reporter (Ace2N-mNeon) with a spectrally compatible calcium sensor (R-GECO) to create a sensitive high throughput method for in vivo characterization of the cardiac AP. Methods Ace2N-mNeon and R-GECO were expressed under control of a myocardial specific promoter via the Tol2kit system. The effect of sensor expression on normal physiology was assessed by patch clamp experiments. Fluorescence recordings were obtained with a Leica SP8 DLS microscope and a custom-built light sheet microscope. Our zebrafish sensor line was validated by experiments with quinidine drug exposure, as well as a novel model for long QT syndrome (LQTS) with a knock-in (KI) mutation in the cacna1c gene. Results Sensor expression did not significantly alter cardiac electrophysiology. The tg(myl7:Ace2N-mNeon/R-GECO) line demonstrated alterations in the heart rate, depolarization and repolarization induced by quinidine exposure. We observed a significantly prolonged ventricular repolarization in the LQTS KI line. Three-dimensional optical maps of AP characteristics across the entire zebrafish heart exhibited the physiological characteristics of the zebrafish cardiac electrophysiology, with activation initiated at the atrial venous pole and propagated towards the ventricular outflow tract, prolonged repolarization in the ventricles compared to the atria and slowed depolarization in the atrio-ventricular canal. Conclusion By expressing Ace2N-mNeon and R-GECO in the zebrafish heart, we were able to accurately detect drug- and mutation induced alterations in the cardiac AP, as well as AP characteristics across the entire heart, without compromising normal cardiac electrophysiology. Our transgenic line will provide a promising assay for future studies of cardiac arrhythmia.
The calcium-sensing-receptor (CaSR) in adipocytes contributes to sex-differences in the susceptibility to high fat diet induced obesity and atherosclerosis
Authors: S L Maas, S Adam, R Huchzermeier, K Abschlag, M Hohl, D Santovito, J Jankowski, E A L Biessen, E P C Van Der Vorst
Journal: Cardiovascular Research (2024)

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): IZKF Female mice are more resistant to the obesogenic effects of a high-fat diet (HFD), compared to male mice. Although the underlying mechanisms are poorly understood, sex hormones seem to play an important role. Interestingly, the activity of the estrogen receptor-α (ERα) is affected by the calcium-sensing-receptor (CaSR). Therefore, we investigated sex-differences upon HFD feeding and the role of adipocyte-specific CaSR herein. Adipocyte-specific Casr deficient mice (AdipoqCre+Casrflox) and control mice (Casrflox) were injected with AAV8-PCSK9 and fed a HFD for 12 weeks. Female mice have a lower visceral white adipose tissue (vWAT) mass then male mice, while this sex-difference is abolished upon adipocyte-specific Casr deficiency. Furthermore, while females showed an increase of IL-6, TNF-α and CCL2 in vWAT, compared to males, adipocyte-specific Casr deficiency rescued this sex-phenotype and demonstrated an inhibition of inflammatory signaling pathways. The expression of Erα, as well as associated genes involved in adipocyte differentiation, was increased in female mice in a mostly adipocyte-specific Casr dependent manner. Interestingly, circulating lipid levels were reduced in female compared to male mice, which coincided and correlated with decreased atherosclerotic plaque formation. These systemic effects were abrogated upon adipocyte-specific Casr deficiency. Our findings indicate that female mice show a more pronounced obesity associated vWAT dysfunction compared to males. This sex effect is abolished in mice with an adipocyte-specific Casr deficiency. In contrast, females show a diminished hyperlipidemic response to HFD feeding and less atherosclerotic plaque formation compared to males, an effect that was rescued by adipocyte-specific Casr deficiency.