Positive and negative regulation of angiogenesis by soluble vascular endothelial growth factor receptor-1

Vascular endothelial growth factor receptor (VEGFR)-1 exists in different forms, derived from alternative splicing of the same gene. In addition to the transmembrane form, endothelial cells produce a soluble VEGFR-1 (sVEGFR-1) isoform, whereas non-endothelial cells produce both sVEGFR-1 and a different soluble molecule, known as soluble fms-like tyrosine kinase (sFlt)1-14. By binding members of the vascular endothelial growth factor (VEGF) family, the soluble forms reduce the amounts of VEGFs available for the interaction with their transmembrane receptors, thereby negatively regulating VEGFR-mediated signaling. In agreement with this activity, high levels of circulating sVEGFR-1 or sFlt1-14 are associated with different pathological conditions involving vascular dysfunction. Moreover, sVEGFR-1 and sFlt1-14 have an additional role in angiogenesis: they are deposited in the endothelial cell and pericyte extracellular matrix, and interact with cell membrane components. Interaction of sVEGFR-1 with α5β1 integrin on endothelial cell membranes regulates vessel growth, triggering a dynamic, pro-angiogenic phenotype. Interaction of sVEGFR-1/sFlt1-14 with cell membrane glycosphingolipids in lipid rafts controls kidney cell morphology and glomerular barrier functions. These cell-matrix contacts represent attractive novel targets for pharmacological intervention in addition to those addressing interactions between VEGFs and their receptors

Novel compound mutations in the mitochondrial translation elongation factor (TSFM) gene cause severe cardiomyopathy with myocardial fibro-adipose replacement

Primary mitochondrial dysfunction is an under-appreciated cause of cardiomyopathy, especially when cardiac symptoms are the unique or prevalent manifestation of disease. Here, we report an unusual presentation of mitochondrial cardiomyopathy, with dilated phenotype and pathologic evidence of biventricular fibro-adipose replacement, in a 33-year old woman who underwent cardiac transplant. Whole exome sequencing revealed two novel compound heterozygous variants in the TSFM gene, coding for the mitochondrial translation elongation factor EF-Ts. This protein participates in the elongation step of mitochondrial translation by binding and stabilizing the translation elongation factor Tu (EF-Tu). Bioinformatics analysis predicted a destabilization of the EF-Ts variants complex with EF-Tu, in agreement with the dramatic steady-state level reduction of both proteins in the clinically affected myocardium, which demonstrated a combined respiratory chain enzyme deficiency. In patient fibroblasts, the decrease of EF-Ts was paralleled by up-regulation of EF-Tu and induction of genes involved in mitochondrial biogenesis, along with increased expression of respiratory chain subunits and normal oxygen consumption rate. Our report extends the current picture of morphologic phenotypes associated with mitochondrial cardiomyopathies and confirms the heart as a main target of TSFM dysfunction. The compensatory response detected in patient fibroblasts might explain the tissue-specific expression of TSFM-associated disease

The proposal of a preventive conservation of an oil sketch by Anthony Van Dyke belonging to a private valencian collection

El diagnóstico que se realizó en un original de Van Dyck que actualmente se conserva en una colección privada valenciana para posteriormente desarrollar la propuesta de conservación preventiva oportuna introdujo a los autores de este artículo en una investigación rigurosa que ha permitido entender la técnica de la citada obra en relación a toda la trayectoria artística de este pintor. Esto supuso contrastar los datos histórico-artísticos que se recabaron en torno a los materiales y a las técnicas artísticas de Van Dyck con los que fueron reunidos en la última década en el Departamento de Conservación del Museo Nacional del Prado a raíz de las intervenciones que allí han experimentado varias de las obras de este autor, al igual que interpretar la citada comparativa a la luz de la información existente en torno al mercado del arte de la época. El resultado es un trabajo que centra la técnica de la pintura que es objeto de nuestro estudio en el panorama artístico-social y cultural en la que surgió, a la par que permite entender aspectos muy concretos de su estado de conservación que deberán tenerse en cuenta al elaborar su propuesta de conservación preventiva.The diagnosis carried out on an original by Van Dyke, that is currently conserved in a private Valencian collection, in order to develop the proposal of preventive conservation, has given the opportunity to the authors of this article in the form of rigorous research, enabling them to understand the technique of the above mentioned work in relation to the whole artistic trajectory of the painter. This meant contrasting the historic-artistic data obtained from the materials and the artistic techniques of Van Dyke with those that were grouped in the last decade at the Department of Conservation of the National Museum Prado. This was a result of the interventions that had undergone various works by this artist as well as to interpret the already mentioned comparison in light of the existing information about the art market of that period. The result is a piece of work that concentrates on the painterly technique which is the purpose of our study in the socio-artistic and cultural panorama in which it arose, as well as understanding the concrete aspects of its conservation state that should be taken into consideration when preparing the proposal for preventive conservation.Vázquez De Agredos Pascual, ML.; Yusa Marco, DJ.; Domenech Carbo, MT.; Rodríguez Gómez, M. (2008). En torno a la propuesta de conservación preventiva de un boceto al óleo de Anton van Dyck perteneciente a una colección privada valenciana. Arché. (3):167-172. http://hdl.handle.net/10251/31766167172

Proteomic and functional analyses reveal pleiotropic action of the anti-tumoral compound NBDHEX in Giardia duodenalis

Giardiasis, a parasitic diarrheal disease caused by Giardia duodenalis, affects one billion people worldwide. Treatment relies only on a restricted armamentarium of drugs. The disease burden and the increase in treatment failure highlight the need for novel, safe and well characterized drug options. The antitumoral compound NBDHEX is effective in vitro against Giardia trophozoites and inhibits glycerol-3-phosphate dehydrogenase. Aim of this work was to search for additional NBDHEX protein targets. The intrinsic NBDHEX fluorescence was exploited in a proteomic analysis to select and detect modified proteins in drug treated Giardia. In silico structural analysis, intracellular localization and functional assays were further performed to evaluate drug effects on the identified targets. A small subset of Giardia proteins was covalently bound to the drug at specific cysteine residues. These proteins include metabolic enzymes, e.g. thioredoxin reductase (gTrxR), as well as elongation factor 1B-gamma (gEF1B gamma), and structural proteins, e.g. alpha-tubulin. We showed that NBDHEX in vitro binds to recombinant gEF1B gamma and gTrxR, but only the last one could nitroreduce NBDHEX leading to drug modification of gTrxR catalytic cysteines, with concomitant disulphide reductase activity inhibition and NADPH oxidase activity upsurge. Our results indicate that NBDHEX reacts with multiple targets whose roles and/or functions are specifically hampered. In addition, NBDHEX is in turn converted to reactive intermediates extending its toxicity. The described NBDHEX pleiotropic action accounts for its antigiardial activity and encourages the use of this drug as a promising alternative for the future treatment of giardiasis. (C) 2017 The Authors. Published by Elsevier Ltd on behalf of Australian Society for Parasitology

In Vivo Targeting of Cutaneous Melanoma Using an Melanoma Stimulating Hormone-Engineered Human Protein Cage with Fluorophore and Magnetic Resonance Imaging Tracers

Nanoparticle (NP)-based materials are promising agents for enhancing cancer diagnosis and treatment. Once functionalized for selective targeting of tumor-expressed molecules, they can specifically deliver drugs and diagnostic molecules inside tumor cells. In the present work, we evaluated the in vivo melanoma-targeting ability of a nanovector (HFt-MSH-PEG) based on human protein ferritin (HFt), functionalized with both melanoma-targeting melanoma stimulating hormone (α-MSH) and stabilizing poly(ethylene glycol) (PEG) molecules. Independent and complementary techniques, such as whole-specimen confocal microscopy and magnetic resonance imaging, were used to detect in vivo localization of NP constructs with suitable tracers (i.e., fluorophores or magnetic metals). Targeted HFt-MSH-PEG NPs accumulated persistently at the level of primary melanoma and with high selectivity with respect to other organs. Melanoma localization of untargeted HFt-PEG NPs, which lack the α-MSH moiety, was less pronounced. Furthermore, HFt-MSH-PEG NPs accumulated to a significantly lower extent and with a different distribution in a diverse type of tumor (TS/A adenocarcinoma), which does not express α-MSH receptors. Finally, in a spontaneous lung metastasis model, HFt-MSH-PEG NPs localized at the metastasis level as well. These results suggest that HFt-MSH-PEG NPs are suitable carriers for selective in vivo delivery of diagnostic or therapeutic agents to cutaneous melanoma

A Smart Platform for Hyperthermia Application in Cancer Treatment: Cobalt-Doped Ferrite Nanoparticles Mineralized in Human Ferritin Cages

Magnetic nanoparticles, MNPs, mineralized within a human ferritin protein cage, HFt, can represent an appealing platform to realize smart therapeutic agents for cancer treatment by drug delivery and magnetic fluid hyperthermia, MFH. However, the constraint imposed by the inner diameter of the protein shell (<i>ca.</i> 8 nm) prevents its use as heat mediator in MFH when the MNPs comprise pure iron oxide. In this contribution, we demonstrate how this limitation can be overcome through the controlled doping of the core with small amount of Co(II). Highly monodisperse doped iron oxide NPs with average size of 7 nm are mineralized inside a genetically modified variant of HFt, carrying several copies of α-melanocyte-stimulating hormone peptide, which has already been demonstrated to have excellent targeting properties toward melanoma cells. HFt is also conjugated to poly(ethylene glycol) molecules to increase its <i>in vivo</i> stability. The investigation of hyperthermic properties of HFt-NPs shows that a Co doping of 5% is enough to strongly enhance the magnetic anisotropy and thus the hyperthermic efficiency with respect to the undoped sample. <i>In vitro</i> tests performed on B16 melanoma cell line demonstrate a strong reduction of the cell viability after treatment with Co doped HFt-NPs and exposure to the alternating magnetic field. Clear indications of an advanced stage of apoptotic process is also observed from immunocytochemistry analysis. The obtained data suggest this system represents a promising candidate for the development of a protein-based theranostic nanoplatform