90 research outputs found

    Vascularised cardiac spheroids-on-a-chip for testing the toxicity of therapeutics.

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    Microfabricated organ-on-a-chips are rapidly becoming the gold standard for the testing of safety and efficacy of therapeutics. A broad range of designs has emerged, but recreating microvascularised tissue models remains difficult in many cases. This is particularly relevant to mimic the systemic delivery of therapeutics, to capture the complex multi-step processes associated with trans-endothelial transport or diffusion, uptake by targeted tissues and associated metabolic response. In this report, we describe the formation of microvascularised cardiac spheroids embedded in microfluidic chips. Different protocols used for embedding spheroids within vascularised multi-compartment microfluidic chips were investigated first to identify the importance of the spheroid processing, and co-culture with pericytes on the integration of the spheroid within the microvascular networks formed. The architecture of the resulting models, the expression of cardiac and endothelial markers and the perfusion of the system was then investigated. This confirmed the excellent stability of the vascular networks formed, as well as the persistent expression of cardiomyocyte markers such as cTNT and the assembly of striated F-actin, myosin and α-actinin cytoskeletal networks typically associated with contractility and beating. The ability to retain beating over prolonged periods of time was quantified, over 25 days, demonstrating not only perfusability but also functional performance of the tissue model. Finally, as a proof-of-concept of therapeutic testing, the toxicity of one therapeutic associated with cardiac disfunction was evaluated, identifying differences between direct in vitro testing on suspended spheroids and vascularised models

    Hipoglucemiantes. – Altramuz (Lupinus albus L.). IV. Actividad de los extractos acuosos

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    Puesta de manifiesto la acción antihiper e hipoglucemiante del Lupinus albus L. en trabajos anteriores, pretendemos ahora estudiar la solubilidad en agua de sus principios activos así como su termo estabilidad en medio acuoso.Once we have stated the antihiper and hypoglycemiant action of the Lupinus albus L. preceding works, we are trying to study the solubility of its elements in water, as well as its termostability in a watery medium

    Estudio comparativo de fármacos antidiabéticos orales. – III. Actividad antihiperglucemiante frente a la sobrecarga endovenosa de glucosa

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    En el presente trabajo se compara la actividad antihiperglucemiante frente a sobrecarga endovenosa de glucosa, de los treinta y dos antidiabéticos orales comercializados en nuestro país; empleándose conejos como animal de experimentación. Se ha realizado el estudio con dosis diferentes y administrando el fármaco antes de la sobrecarga de glucosa, así como simultáneamente a ella.The antihiperglucemic activity of the thirty two oral antidiabetic comercialized in Spain toward an endovenous overdose of glucose has been studied and compared, using rabbits as experimentation animals. The study has been carried out using two different doses and administering the drug either before the overdose of glucose or simultaneously with it

    Hypertensive pressure mechanosensing alone triggers lipid droplet accumulation and transdifferentiation of vascular smooth muscle cells to foam cells

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    Arterial Vascular smooth muscle cells (VSMCs) play a central role in the onset and progression of atherosclerosis. Upon exposure to pathological stimuli, they can take on alternative phenotypes that, among others, have been described as macrophage like, or foam cells. VSMC foam cells make up >50% of all arterial foam cells and have been suggested to retain an even higher proportion of the cell stored lipid droplets, further leading to apoptosis, secondary necrosis, and an inflammatory response. However, the mechanism of VSMC foam cell formation is still unclear. Here, it is identified that mechanical stimulation through hypertensive pressure alone is sufficient for the phenotypic switch. Hyperspectral stimulated Raman scattering imaging demonstrates rapid lipid droplet formation and changes to lipid metabolism and changes are confirmed in ABCA1, KLF4, LDLR, and CD68 expression, cell proliferation, and migration. Further, a mechanosignaling route is identified involving Piezo1, phospholipid, and arachidonic acid signaling, as well as epigenetic regulation, whereby CUT&Tag epigenomic analysis confirms changes in the cells (lipid) metabolism and atherosclerotic pathways. Overall, the results show for the first time that VSMC foam cell formation can be triggered by mechanical stimulation alone, suggesting modulation of mechanosignaling can be harnessed as potential therapeutic strategy

    Interés terapéutico de las estatinas en el tratamiento de la aterosclerosis

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    Los inhibidores de la HMG-Co A reductasa o estatinas, son fármacos muy utilizados en el tratamiento de lahipercolesterolemia, ya que consiguen disminuir la concentración plamática de lipoproteína de baja densidad (LDL)regulando la síntesis endógena de colesterol y por tanto, de receptores para LDL.Recientemente se ha comprobado como el tratamiento prolongado con estos fármacos disminuyen la mortalidad ymorbilidad cardiovascular. Este fenómeno puede explicarse por los efectos beneficiosos directos de las estatinas enel desarrollo de la placa de ateroma. Las estatinas disminuyen la proliferación y migración de células de musculaturalisa vascular e inducen apoptosis de estas células. También previenen la oxidación de LDL y la formación de célulasespumosas, reducen la respuesta inflamatoria asociada a la aterosclerosis, normalizan los fenómenos de coagulacióny fibrinolisis y por último mejoran significativamente la función endotelial. Todas estas propiedades parecen estarmediadas compuestos isoprenoides intermediarios de la ruta metabólica de la HMG-Co A reductasa, y son independientesde la concentración de colesterol en el medio.Por tanto, las estatinas también podrían ser utilizadas en enfermedades asociadas a disfunción endotelial independientementede las cifras analíticas de LDL, tal y como sucede en la hipertensión

    Therapeutical interest of statins in the treatment of atherosclerosis

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    Los inhibidores de la HMG-Co A reductasa o estatinas, son fármacos muy utilizados en el tratamiento de la hipercolesterolemia, ya que consiguen disminuir la concentración plamática de lipoproteína de baja densidad (LDL) regulando la síntesis endógena de colesterol y por tanto, de receptores para LDL. Recientemente se ha comprobado como el tratamiento prolongado con estos fármacos disminuyen la mortalidad y morbilidad cardiovascular. Este fenómeno puede explicarse por los efectos beneficiosos directos de las estatinas en el desarrollo de la placa de ateroma. Las estatinas disminuyen la proliferación y migración de células de musculatura lisa vascular e inducen apoptosis de estas células. También previenen la oxidación de LDL y la formación de células espumosas, reducen la respuesta inflamatoria asociada a la aterosclerosis, normalizan los fenómenos de coagulación y fibrinolisis y por último mejoran significativamente la función endotelial. Todas estas propiedades parecen estar mediadas compuestos isoprenoides intermediarios de la ruta metabólica de la HMG-Co A reductasa, y son independientes de la concentración de colesterol en el medio. Por tanto, las estatinas también podrían ser utilizadas en enfermedades asociadas a disfunción endotelial independientemente de las cifras analíticas de LDL, tal y como sucede en la hipertensión.HMG-Co A reductase inhibitors or statins, are widely used drugs in the treatment of hypercholesterolemia. They lower plasmatic concentration of low density lipoprotein (LDL) by regulating cholesterol synthesis and consequently synthesis of LDL receptors. Chronic treatment with these drugs has recently shown to be able to reduce cardiovascular-related morbidity and mortality. This fact could be explained by a direct benefic effect of statins in development of atherosclerotic plaque. Statins reduce vascular smooth muscle cell proliferation and migration , as well as they induce apoptosis of these cells. They also prevent LDL oxidation and foam cell formation, reducing inflammatory response associated to atherosclerosis, normalising coagulation and fibronolysis and improving endothelial function. All these properties seem to be mediated by intermediary isoprenoid compounds from HMG-Co A reductase metabolic pathway and do not depend of cholesterol concentration in the medium. Thus, statins could also be used in the treatment of some diseases associated to endothelial disfunction, independently of analytical LDL values, like hypertension

    Glioma stem cells invasive phenotype at optimal stiffness is driven by MGAT5 dependent mechanosensing.

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    BACKGROUND: Glioblastomas stem-like cells (GSCs) by invading the brain parenchyma, remains after resection and radiotherapy and the tumoral microenvironment become stiffer. GSC invasion is reported as stiffness sensitive and associated with altered N-glycosylation pattern. Glycocalyx thickness modulates integrins mechanosensing, but details remain elusive and glycosylation enzymes involved are unknown. Here, we studied the association between matrix stiffness modulation, GSC migration and MGAT5 induced N-glycosylation in fibrillar 3D context. METHOD: To mimic the extracellular matrix fibrillar microenvironments, we designed 3D-ex-polyacrylonitrile nanofibers scaffolds (NFS) with adjustable stiffnesses by loading multiwall carbon nanotubes (MWCNT). GSCs neurosphere were plated on NFSs, allowing GSCs migration and MGAT5 was deleted using CRISPR-Cas9. RESULTS: We found that migration of GSCs was maximum at 166 kPa. Migration rate was correlated with cell shape, expression and maturation of focal adhesion (FA), Epithelial to Mesenchymal Transition (EMT) proteins and (β1,6) branched N-glycan binding, galectin-3. Mutation of MGAT5 in GSC inhibited N-glycans (β1-6) branching, suppressed the stiffness dependence of migration on 166 kPa NFS as well as the associated FA and EMT protein expression. CONCLUSION: MGAT5 catalysing multibranched N-glycans is a critical regulators of stiffness induced invasion and GSCs mechanotransduction, underpinning MGAT5 as a serious target to treat cancer

    Coronavirus disease 2019 in patients with inborn errors of immunity: an international study

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    BACKGROUND:There is uncertainty about the impact of SARS-CoV-2 infection in individuals with rare inborn errors of immunity (IEI), a population at risk of developing severe COVID-19. This is relevant not only for these patients but also the general population, as studies of IEIs can unveil key requirements for host defense. OBJECTIVE:Describe the presentation, manifestations and outcome of SARS-CoV-2 infection in IEI to inform physicians and enhance understanding of host defense against SARS-CoV-2. METHODS:An invitation to participate in a retrospective study was distributed globally to scientific, medical and patient societies involved in the care and advocacy for patients with IEI. RESULTS:We gathered information on 94 IEI patients with SARS-CoV-2 infection. Median age was 25-34 years. 53 patients (56%) suffered from primary antibody deficiency, 9 (9.6%) had immune dysregulation syndrome, 6 (6.4%) a phagocyte defect, 7 (7.4%) auto-inflammatory disorder, 14 (15%) a combined immunodeficiency, 3 (3%) an innate immune defect, and 2 (2%) bone marrow failure. Ten were asymptomatic, 25 were treated as outpatients, 28 required admission without intensive care or ventilation, 13 required non-invasive ventilation or oxygen administration, 18 were admitted to intensive care units, 12 requiring invasive ventilation, and 3 extra corporeal membrane oxygenation. Nine patients (seven adults, two children) died. CONCLUSIONS:This study demonstrates that (1) >30% of IEI patients had mild COVID19, and (2) risk factors predisposing to severe disease/mortality in the general population also seemed to affect IEI patients, including more younger patients. Further studies will identify pathways that are associated with increased risk of severe disease and are non-redundant or redundant for protection against SARS-CoV-2.Isabelle Meyts, Giorgia Bucciol, Isabella Quinti, Bénédicte Neven, Alain Fischer, Elena Seoan

    Demographic, clinical and antibody characteristics of patients with digital ulcers in systemic sclerosis: data from the DUO Registry

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    OBJECTIVES: The Digital Ulcers Outcome (DUO) Registry was designed to describe the clinical and antibody characteristics, disease course and outcomes of patients with digital ulcers associated with systemic sclerosis (SSc). METHODS: The DUO Registry is a European, prospective, multicentre, observational, registry of SSc patients with ongoing digital ulcer disease, irrespective of treatment regimen. Data collected included demographics, SSc duration, SSc subset, internal organ manifestations, autoantibodies, previous and ongoing interventions and complications related to digital ulcers. RESULTS: Up to 19 November 2010 a total of 2439 patients had enrolled into the registry. Most were classified as either limited cutaneous SSc (lcSSc; 52.2%) or diffuse cutaneous SSc (dcSSc; 36.9%). Digital ulcers developed earlier in patients with dcSSc compared with lcSSc. Almost all patients (95.7%) tested positive for antinuclear antibodies, 45.2% for anti-scleroderma-70 and 43.6% for anticentromere antibodies (ACA). The first digital ulcer in the anti-scleroderma-70-positive patient cohort occurred approximately 5 years earlier than the ACA-positive patient group. CONCLUSIONS: This study provides data from a large cohort of SSc patients with a history of digital ulcers. The early occurrence and high frequency of digital ulcer complications are especially seen in patients with dcSSc and/or anti-scleroderma-70 antibodies

    BacHBerry: BACterial Hosts for production of Bioactive phenolics from bERRY fruits

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    BACterial Hosts for production of Bioactive phenolics from bERRY fruits (BacHBerry) was a 3-year project funded by the Seventh Framework Programme (FP7) of the European Union that ran between November 2013 and October 2016. The overall aim of the project was to establish a sustainable and economically-feasible strategy for the production of novel high-value phenolic compounds isolated from berry fruits using bacterial platforms. The project aimed at covering all stages of the discovery and pre-commercialization process, including berry collection, screening and characterization of their bioactive components, identification and functional characterization of the corresponding biosynthetic pathways, and construction of Gram-positive bacterial cell factories producing phenolic compounds. Further activities included optimization of polyphenol extraction methods from bacterial cultures, scale-up of production by fermentation up to pilot scale, as well as societal and economic analyses of the processes. This review article summarizes some of the key findings obtained throughout the duration of the project
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