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Ibanez, B.

Publications and source records attributed to Ibanez, B..

11 recordsLinked to original sources

Endothelial β3-Adrenergic Receptor activation prevents pulmonary hypertension

BackgroundPulmonary hypertension (PH) is a progressive vascular disease characterized by endothelial dysfunction, vascular remodeling and increased pulmonary vascular resistance. The {beta}3-adrenergic receptor ({beta}3-AR) has been implicated in cardiovascular regulation and cardioprotective mechanisms; however, its role in pulmonary vascular disease remains poorly understood. We investigated whether activation of {beta}3-AR protects pulmonary endothelial function and prevents the development of pre-capillary PH. Methods{beta}3-AR expression was evaluated in pulmonary endothelium from patients with Chronic Obstructive Pulmonary Disease (COPD) and in murine models of hypoxia-induced PH. Genetic mouse models including {beta}3-AR knockout (KO) and conditional {beta}3-AR overexpression in endothelial cells (EC) or in smooth muscle cells (SMC), were used to determine cell-specific roles. Pharmacological activation of {beta}3-AR was achieved using the selective {beta}3-agonist mirabegron in hypoxia-induced PH mice and monocrotaline-induced PH rats. Pulmonary vascular reactivity and vasodilatory responses to {beta}3-AR stimulation were evaluated by wire myography in isolated pulmonary arteries. Mechanistic studies were performed in human pulmonary artery endothelial cells (HPAEC) under hypoxic conditions, in human pulmonary arterial smooth muscle cells (HPASMC) and in endothelial nitric oxide synthase (NOS3) KO mice. Results{beta}3-AR was upregulated in pulmonary endothelium of COPD patients and mice exposed to chronic hypoxia. Genetic deletion of {beta}3-AR aggravated PH, whereas endothelial-specific overexpression attenuated the disease phenotype, reducing right ventricular systolic pressure (RVSP), vascular remodeling and right ventricular (RV) hypertrophy. Activation of {beta}3-AR with mirabegron improved pulmonary hemodynamics, reduced vascular remodeling and preserved RV function. {beta}3-AR activation promoted endothelial nitric oxide synthase (eNOS)-dependent NO production, indirectly inhibiting SMC proliferation. Additionally, {beta}3-AR activation improved mitochondrial fitness in endothelial cells by increasing uncoupling protein 2 (UCP2) expression, reducing reactive oxygen species (ROS) generation and preventing mitochondrial fragmentation. ConclusionsThese findings identify endothelial {beta}3-AR as a previously unrecognized regulator of pulmonary vascular homeostasis and provide a strong translational rationale for targeting the {beta}3-adrenergic pathway in PH. Given that mirabegron is already approved for clinical use, our results support its repurposing as a therapeutic strategy for pre-capillary forms of PH.

pharmacology and toxicology↗

Towards whole-heart quantitative myocardial perfusion using a dual-sequence framework with multiband acceleration

Background2D Quantitative Myocardial Perfusion (Qperf) MRI is limited by its inability to provide complete myocardial coverage within a heartbeat interval. This study developed and evaluated dual saturation multiband-accelerated Qperf imaging to achieve near-complete left ventricular coverage in free-breathing at an adequate in-plane spatial resolution, using a semi-automated Myocardial Blood Flow (MBF) framework for quantification deployable directly on the scanner console. MethodsA dual-saturation single-band QPerf sequence was modified for multiband imaging, enabling the acquisition of 6 high-resolution myocardial slices plus Arterial Input Function (AIF) during free-breathing. The technique was evaluated in 16 sedated pigs (13 healthy and 3 with LAD occlusion) under rest conditions on a 3T MRI scanner. Additionally, two healthy pigs underwent stress imaging as well. Statistical comparisons were performed between multiband and single-band MBF values in corresponding AHA segments. ResultsQualitatively, multiband QPerf provided superior left ventricular coverage and comparable image quality to single-band Qperf MBF maps, potentially enabling a more comprehensive detection of perfusion defects at rest. Quantitatively, multiband QPerf yielded lower MBF values than single-band QPerf (p < 0.01). However, Bland-Altman analysis (mean difference: -0.17 ml/min/g; 95% CI: -1.12 to 0.79 ml/min/g) and Passing-Bablok regression (intercept: -0.01 ml/min/g; 95% CI: - 0.37 to 0.28 ml/min/g) indicated that such discrepancy remained within the expected confidence intervals. Furthermore, the Passing-Bablok slope (0.88; 95% CI: 0.73-1.06) confirmed that mb-QPerf maintained sensitivity comparable to sb-QPerf in detecting perfusion changes under rest conditions. Finally, there was an overall increase in MBF values during stress vs rest conditions (average MBF Ratio 1.67 {+/-} 0.31) when comparing healthy pigs. ConclusionMultiband-accelerated Qperf is feasible, providing improved left ventricular coverage, adequate in-plane resolution, and a semi-automated MBF quantification framework directly on the scanner console. Compared to its single-band counterpart, multiband QPerf demonstrated a more comprehensive visualization of perfusion defects and comparable sensitivity and accuracy in detecting perfusion changes at rest. Further research and clinical validation in patient populations are needed to confirm its utility in the diagnosis of coronary artery disease.

bioengineering↗

Precon_all: A species-agnostic automated pipeline for non-human cortical surface reconstruction

Cortical surface reconstruction has changed how we study brain morphology and geometry. However, extending these methods to non-human species has been limited by the lack of standardized pipelines, anatomical templates, and variability in imaging protocols. To address these challenges, we present Precon_all, an open-source, species-agnostic pipeline that automates cortical surface reconstruction for non-human neuroimaging. It runs reliably across a wide range of anatomical structures and imaging conditions and has been successfully applied to datasets from primates, carnivores, and artiodactyls. Its modular framework mirrors human neuroimaging workflows, supports manual quality control, and produces outputs compatible with FreeSurfer and Connectome Workbench. In doing so, it substantially reduces technical barriers to non-human neuroimaging. As data-sharing initiatives continue to expand access to non-human imaging datasets, Precon_all provides a scalable and standardized solution that supports the broader adoption of surface-based methods for studying cortical evolution through comparative neuroscience.

neuroscience↗

Integrative multi-layer workflow for quantitative analysis of post-translational modifications

Novel algorithms based on ultratolerant database searching have paved the way for comprehensive analysis of all possible post-translational modifications (PTM) that can be detected by mass spectrometry-based proteomics, obviating their prior knowledge. These tools together with novel quantitative statistical models allow hypothesis-free approaches to study the role and impact of PTM on biological systems. However, interpretation of this information from a pathophysiological perspective is challenging due to the huge amounts of PTM data, the existence of chemical, structural, and statistical artifacts and the lack of dedicated tools for their analysis. Here we propose a novel integrative workflow that automatically captures several layers of PTM-related information, including variations in trypsin efficiency, zonal changes, specific PTM changes and hypermodified regions, allowing advanced control of artefacts and coherent and comprehensive interpretation of PTM data. We show the performance of the new workflow by reanalyzing proteomics data from animal models of mitochondrial heteroplasmy and ischemia/reperfusion, revealing relevant PTM information not previously detectable, including consistent detection of novel oxidative modifications in Met and Cys residues from raw proteomics data. The workflow is available through the application PTM-compass.

bioinformatics↗

Protein aggregation capture assisted profiling of the thiol redox proteome

Oxidative damage is critical in various diseases, including cardiovascular and neurological conditions. Thiol redox reactions, acting as oxidative stress sensors, influence protein structure and function. Redox proteomics based on differential alkylation of reduced and oxidized Cys forms using mass spectrometry enables comprehensive analysis of thiol redox status in cells and tissues. We introduce PACREDOX, an innovative redox proteomics approach based on the Protein Aggregation Capture (PAC) protocol and we demonstrate its compatibility with library free data-independent acquisition (DIA). PACREDOX reduces preparation time and costs compared to traditional methods, such as FASILOX, while maintaining thiol and proteome coverage. To enable library-free DIA, we corrected in silico spectral libraries in DIA-NN using experimental retention time data from beta-methylthiol-modified peptides. PACREDOX with DIA quantified 4,000 protein groups and [~]45,000 modified peptides in myocardial tissue from a porcine model of atrial fibrillation, including over 8,000 cysteine-containing peptides, 30% of which were reversibly oxidized. Benchmarking PACREDOX and DIA against FASILOX in a myocardial infarction model reflects the potential and efficiency of this methodology to study oxidative damage. Overall, PACREDOX offers a high-throughput, cost-effective strategy for thiol redox proteome analysis, compatible with label-free quantitative workflows.

systems biology↗

Extracellular vesicles from preeclampsia disrupt the blood-brain barrier via reduced claudin-5: potential role of vascular endothelial growth factor

BackgroundPhysiopathology of life-treating cerebrovascular complications in preeclampsia are yet unknown. We investigated whether disruption of the blood-brain barrier (BBB), generated using circulating small extracellular vesicles (sEVs) from women with preeclampsia or placentae cultured under hypoxic conditions, impairs the expression of tight junction proteins, such as claudin 5 (CLDN5), mediated by VEGF and activation of VEGF receptor 2 (KDR). MethodssEVs were isolated from plasma (normal pregnancy, sEVs-NP, n=9); preeclampsia, sEVs-PE, n=9) or placental explants from normotensive pregnancies, cultured in normoxia (sEVs-Nor, n=10) or hypoxia (sEVs-Hyp, n=10). The integrity of the BBB was evaluated using in vitro (human and mice brain endothelial cell lines) and in vivo (non-pregnant C57BL/6 mice (4 to 5 months old, (n=10) were injected with sEVs-Hyp), models. ResultssEVs-PE and sEVs-Hyp reduced CLND5 levels (p<0.05) in the endothelial cell membrane without affecting other tight junction proteins. These results were negated with sEVs-PE sonication. sEVs-Hyp injected into non-pregnant mice generated neurological deficits and BBB disruption, specifically in the posterior area of the brain, associated with reduction in CLND5 levels in the brain cortex. Furthermore, sEVs-PE and sEVs-sHyp had higher VEGF levels than sEVs-NP and sEVs-Nor, respectively. Human brain endothelial cells exposed to sEVs-PE or sEVs-sHyp exhibited a reduction in the activation of KDR. ConclusionsEVs from hypoxic placentae and plasma from women with preeclampsia disrupt the BBB, via reduction of CLDN5, a phenomenon that may involve VEGF contained within these vesicles. These findings will improve the elucidation of cerebrovascular alterations in women with preeclampsia.

physiology↗

Allergic inflammation triggers dyslipidemia via IgG signalling

BackgroundAllergic diseases begin early in life and are often chronic, thus creating an inflammatory environment that may precede or exacerbate other pathologies. In this regard, allergy has been associated to metabolic disorders and with a higher risk of cardiovascular disease, but the underlying mechanisms remain incompletely understood. MethodsWe used a murine model of allergy and atherosclerosis, different diets and sensitization methods, and cell-depleting strategies to ascertain the contribution of acute and late phase inflammation to dyslipidemia. Untargeted lipidomic analyses were applied to define the lipid fingerprint of allergic inflammation at different phases of allergic pathology. Expression of genes related to lipid metabolism was assessed in liver and adipose tissue at different times post-allergen challenge. Also, changes in serum triglycerides (TG) were evaluated in a group of 59 patients [&ge;]14 days after the onset of an allergic reaction. ResultsWe found that allergic inflammation induces a unique lipid signature that is characterized by increased serum TG and changes in the expression of genes related to lipid metabolism in liver and adipose tissue. Alterations in blood TGs following an allergic reaction are independent of T-cell-driven late phase inflammation. On the contrary, the IgG-mediated alternative pathway of anaphylaxis is sufficient to induce a TG increase and a unique lipid profile. Lastly, we demonstrated an increase in serum TG in 59 patients after undergoing an allergic reaction. ConclusionOverall, this study reveals that IgG-mediated allergic inflammation regulates lipid metabolism.

immunology↗

GDF15 antagonism limits severe heart failure and prevents cardiac cachexia in mice

Heart failure and associated cachexia is an unresolved and important problem. We report a new model of severe heart failure that consistently results in cachexia. Mice lacking the integrated stress response (ISR) induced eIF2 phosphatase, PPP1R15A, exhibit a dilated cardiomyopathy and severe weight loss following irradiation, whilst wildtype mice are unaffected. This is associated with increased expression of Gdf15 in the heart and increased levels of GDF15 in the circulation. We provide evidence that blockade of GDF15 activity prevents cachexia and slows the progression of heart failure. Our data suggests that cardiac stress mediates a GDF15 dependent pathway that drives weight loss and worsens cardiac function. We show relevance of GDF15 to lean mass and protein intake with patients with heart failure. Blockade of GDF15 could constitute a novel therapeutic option to limit cardiac cachexia and improve clinical outcomes in patients with severe systolic heart failure.

pathology↗

Planar cell polarity: intracellular asymmetry and supracellular gradients of Dachsous

The slope of a supracellular molecular gradient has long been thought to orient and coordinate planar cell polarity (PCP). Here we demonstrate and measure that gradient. Dachsous (Ds) is a conserved and elemental molecule of PCP; Ds forms intercellular bridges with another cadherin molecule, Fat (Ft), an interaction modulated by the Golgi protein Four- jointed (Fj). Using genetic mosaics and tagged Ds we measure Ds in vivo in membranes of individual cells over a whole metamere of the Drosophila abdomen. We find: 1. A supracellular gradient that rises from head to tail in the anterior compartment (A) and then falls in the posterior compartment (P). 2. There is more Ds in the front than the rear membranes of all cells in the A compartment, except that compartments most anterior and most posterior cells. There is more Ds in the rear than in the front membranes of all cells of the P compartment 3. The loss of Fj removes intracellular asymmetry anteriorly in the segment and reduces it elsewhere. Additional experiments show that Fj makes PCP more robust. Using Dachs (D) as a molecular indicator of polarity, we confirm that opposing gradients of PCP meet slightly out of register with compartment boundaries.

developmental biology↗

A White Matter Atlas and Common Connectivity Space Facilitate the Pig as a Translational Model in Neuroscience

Neuroimagings capability to quickly and rapidly phenotype the cortical organization of the whole brain brings with it the possibility to extend our understanding of cortical organization across the mammalian lineage. However, neuroimaging has thus far generally limited itself to a small number of species, with most animal studies being performed in either rodents or Non-Human Primates. Here we perform a first pass characterization of an animal which has recently seen its stock rise in the neuroscience community with the development of new models of neurological disease; the domestic pig. Characterizing the structural connectome of the pig, we create a white matter atlas, and an anatomical template which we use to build a horizontal translation between the pig and human based on a connectivity blueprint approach. We find that conserved trends of structural connectivity across species enabled spatial prediction of regions of interest between the pig and human, showing the potential horizontal translations have as a tool to assess the translational validity of porcine models of neurological disease. Releasing the anatomical template, white matter atlas, and connectivity blueprints, we hope to ease and promote the acceptance of the pig as an alternative large-animal model by the neuroimaging community.

neuroscience↗

Remote Ischemic Preconditioning Ameliorates Anthracycline-induced Cardiotoxicity and Preserves Mitochondrial Integrity

AimsAnthracycline-induced cardiotoxicity (AIC) is a serious adverse effect in a significant proportion of cancer patients. A central mechanism of AIC is irreversible mitochondrial damage. Despite major efforts, there are currently no effective therapies able to prevent AIC. Methods and ResultsForty Large-White pigs were included. In Study 1, 20 pigs were randomized 1:1 to remote ischemic pre-conditioning (RIPC, 3 cycles of 5 min leg ischemia followed by 5 min reperfusion) or no pretreatment. RIPC was performed immediately before each of five intracoronary doxorubicin injections (0.45 mg/kg) given at weeks 0, 2, 4, 6, and 8. A group of 10 pigs with no exposure to doxorubicin served as healthy controls. Pigs underwent serial cardiac magnetic resonance (CMR) exams at baseline and at weeks 6, 8, 12, and 16. After 16-week CMR, pigs were sacrificed and tissue samples collected. In study 2, 10 new pigs received 3 doxorubicin injections (with/out preceding RIPC) and were sacrificed 2 weeks after the third dose. In Study 1, LVEF remained unchanged in doxorubicin-treated pigs until week 6 (time of the fourth doxorubicin injection). From there on, LVEF progressively declined, but LVEF depression was blunted animals receiving RIPC before doxorubicin (RIPC-Doxo), which had a significantly higher LVEF at week 16 than doxorubicin treated pigs that received no pretreatment (Untreated-Doxo) (41.5{+/-}9.1% vs 32.5{+/-}8.7%, p=0.04). Preserved LVEF was mainly due to conserved contractile function, as evidenced by smaller LVESV, and better regional contractile function. In Study 2, transmission electron microscopy (TEM) after 3 doxorubicin doses showed fragmented mitochondria with severe morphological abnormalities in RIPC+Doxo pigs, together with upregulation of fission proteins and autophagy markers on western blot. At the end of the 16-week Study 1 protocol, TEM revealed overt mitochondrial fragmentation with structural fragmentation in Untreated-Doxo pigs, whereas interstitial fibrosis was significantly less severe in the RIPC+Doxo pigs. ConclusionIn a translatable large animal model of AIC, RIPC applied immediately before each doxorubicin injection resulted in preserved cardiac contractility with significantly higher long-term LVEF and less cardiac fibrosis. RIPC prevented mitochondrial fragmentation and dysregulated autophagy from the early stages of AIC. RIPC is a promising intervention for testing in clinical trials in AIC.

molecular biology↗