Método de detección de la Telangiectasia Hemorrágica Hereditaria

Método de detección de la Telangiectasia Hemorrágica Hereditaria. Método para la detección de la Telangiectasia Hemorrágica Hereditaria (HHT) que comprende el análisis in vitro de los productos de la expresión de los genes ENG o FLT1 Y ENG o ANGPT2 en muestras biológicas de pacientes y que, además, permite sub-clasificar las variantes HHT1 y HHT2 de la enfermedad. En particular, la presente invención se refiere a un kit para la detección molecular de HHT capaz de llevar a cabo la detección mencionada anteriormente.Peer reviewedConsejo Superior de Investigaciones Científicas (España), Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER)A1 Solicitud de patentes con informe sobre el estado de la técnic

Intra- and intergenotypic larval competition in Drosophila melanogaster : effect of larval density and biotic residues

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Local sclerotherapy with Polydocanol (Aethoxysklerol®) for the treatment of Epistaxis in Rendu-Osler-Weber or Hereditary Hemorrhagic Telangiectasia (HHT): 15 years of experience*

Producción CientíficaHereditary Haemorrhagic Telangiectasia or Rendu-Osler-Weber syndrome is a rare autosomal dominant vascular disease characterized by mucocutaneous and gastrointestinal telangiectases and localized arteriovenous malformations in lung, brain and liver. Epistaxis, due to rupture of telangiectases of the nasal mucosa, is the most frequent clinical manifestation, leading in many cases to severe impairment of the quality of life in the patients. Though several treatments have been used to reduce epistaxis, none have been completely effective, with the exception of polydocanol (Aethoxysklerol®) in submucosal or subpericondrial injections, which was first presented in 2000 with very good results. After fifteen years using polydocanol in submucosal injections on 45 patients and with nearly 300 injections, we have observed that in 95% of all cases, their nose bleeds improved with respect to frequency and quantity without any important side effects. There was just one case of septal perforation, another with increased septal perforation, and one patient who suffered from dizziness and blurred vision for a few minutes. In this paper the results obtained using this technique over a fifteen-year period will be presented and evaluated

Mutation affecting the proximal promoter of Endoglin as the origin of hereditary hemorrhagic telangiectasia type 1

[Background] Hereditary hemorrhagic telangiectasia (HHT) is a vascular multi-organ system disorder. Its diagnostic criteria include epistaxis, telangiectases in mucocutaneous sites, arteriovenous malformations (AVMs), and familial inheritance. HHT is transmitted as an autosomal dominant condition, caused in 85% of cases by mutations in either Endoglin (ENG) or Activin receptor-like kinase (ACVRL1/ACVRL1/ALK1) genes. Pathogenic mutations have been described in exons, splice junctions and, in a few cases with ENG mutations, in the proximal promoter, which creates a new ATG start site. However, no mutations affecting transcription regulation have been described to date in HHT, and this type of mutation is rarely identified in the literature on rare diseases.[Methods] Sequencing data from a family with HHT lead to single nucleotide change, c.-58G > A. The functionality and pathogenicity of this change was analyzed by in vitro mutagenesis, quantitative PCR and Gel shift assay. Student t test was used for statistical significance.[Results] A single nucleotide change, c.-58G > A, in the proximal ENG promoter co-segregated with HHT clinical features in an HHT family. This mutation was present in the proband and in 2 other symptomatic members, whereas 2 asymptomatic relatives did not harbor the mutation. Analysis of RNA from activated monocytes from the probands and the healthy brother revealed reduced ENG mRNA expression in the HHT patient (p = 0.005). Site-directed mutagenesis of the ENG promoter resulted in a three-fold decrease in luciferase activity of the mutant c.-58A allele compared to wild type (p = 0.005). Finally, gel shift assay identified a DNA-protein specific complex.[Conclusions] The novel ENG c.-58G > A substitution in the ENG promoter co-segregates with HHT symptoms in a family and appears to affect the transcriptional regulation of the gene, resulting in reduced ENG expression. ENG c.-58G > A may therefore be a pathogenic HHT mutation leading to haploinsufficiency of Endoglin and HHT symptoms. To the best of our knowledge, this is the first report of a pathogenic mutation in HHT involving the binding site for a transcription factor in the promoter of ENG.This study has been supported by grants from Ministerio de Economia y Competitividad of Spain (SAF2011-23475 and SAF2014-52374-R) to L.M. Botella and Centro de Investigación Biomedica en Red de Enfermedades Raras (CIBERER).Peer reviewe

Characterization of chicken endoglin, a member of the zona pellucida family of proteins, and its tissue expression

Endoglin is a TGF-β co-receptor expressed in endothelial cells, where it plays a crucial role in angiogenesis, cardiovascular development and vascular remodeling. In humans, mutations in the endoglin gene give rise to Hereditary Hemorrhagic Telangiectasia type 1 (HHT1), an autosomal dominant disorder associated with vascular lesions in skin, mucosa and internal organs. So far, endoglin cDNA has been sequenced in several species from mammals, amphibians and birds. While in mammals the characterization of endoglin protein expression and function is well documented, little is known about the protein homologue in birds. In silico analysis by multiple sequences alignment showed a low homology score of 30-33 between the full length chicken endoglin protein and several mammalian homologues. However, a high homology score (80-85) was observed with the cytoplasmic and transmembrane regions and the overall structure of the zona pellucida (ZP) and orphan domains of the extracellular region appear to be conserved. Transient expression of chicken endoglin allowed the identification of a 180-kDa disulfide linked homodimer similar to the mammalian homologues. To further characterize its tissue expression, the novel specific monoclonal antibody (mAb) 7H5A8 was generated against chicken endoglin transfectant cells. The mAb 7H5A8 specifically recognized chicken endoglin by western blot, immunoprecipitation, immunofluorescence flow cytometry as well as immunofluorescence microscopy assays and displayed a positive staining of the endothelium in veins and arteries from frozen tissue sections of lung and bursa of Fabricius. These results may help to further understand the endoglin expression in vertebrates. © 2011 Elsevier B.V.Ministerio de Ciencia e Innovación of Spain (SAF2010-19222 to CB and BFU2010-19144 to CC); Genoma España (MEICA); Centro de Investigación Biomédica en Red de Enfermedades Raras; Fondo de Investigaciones Sanitarias; European Union (PI081813)Peer Reviewe

5'UTR mutations of ENG cause hereditary hemorrhagic telangiectasia

<p>Abstract</p> <p>Background</p> <p>Hereditary hemorrhagic telangiectasia (HHT) is a vascular disorder characterized by epistaxis, arteriovenous malformations, and telangiectases. The majority of the patients have a mutation in the coding region of the activin A receptor type II-like 1 (<it>ACVRL1</it>) or Endoglin (<it>ENG</it>) gene. However, in approximately 15% of cases, sequencing analysis and deletion/duplication testing fail to identify mutations in the coding regions of these genes. Knowing its vital role in transcription and translation control, we were prompted to investigate the 5'untranslated region (UTR) of <it>ENG</it>.</p> <p>Methods and Results</p> <p>We sequenced the 5'UTR of <it>ENG </it>for 154 HHT patients without mutations in <it>ENG </it>or <it>ACVRL1 </it>coding regions. We found a mutation (c.-127C > T), which is predicted to affect translation initiation and alter the reading frame of endoglin. This mutation was found in a family with linkage to the <it>ENG</it>, as well as in three other patients, one of which had an affected sibling with the same mutation. <it>In vitro </it>expression studies showed that a construct with the c.-127C > T mutation alters the translation and decreases the level of the endoglin protein. In addition, a c.-9G > A mutation was found in three patients, one of whom was homozygous for this mutation. Expression studies showed decreased protein levels suggesting that the c.-9G > A is a hypomorphic mutation.</p> <p>Conclusions</p> <p>Our results emphasize the need for the inclusion of the 5'UTR region of <it>ENG </it>in clinical testing for HHT.</p

Screening pulmonary arteriovenous malformations in a large cohort of Spanish patients with hemorrhagic hereditary telangiectasia

39 p.-1 fig.-7 tab.Background and objectives Because of the serious nature of potential complications, screening for pulmonary arteriovenous malformations is required in patients with hereditary hemorrhagic telangiectasia. The aim of this study was to evaluate the utility of contrast echocardiography and compare the performance of two contrast agents: agitated saline and Gelofusine.Material and methods Two hundred and five patients screened for PAVMs using TTCE and computed tomography (CT) performed with an interval of less than 180 days. Contrast echocardiography studies were graded on a 4-point semiquantitative scale based on the amount of microbubbles seen in left heart chambers.Results Positive TTCE findings were seen in 137 (66.8%) patients, whereas CT confirmed PAVMs in 59 (43.1%). Two of 67 grade 1 patients; 18 of 42 grade 2; 17 of 22 grade 3 and all grade 4 had PAVMs on CT. Embolotherapy was feasible in 38.9% patients in grade 2 and 82.3% and 95.2% in grades 3–4. No patients in grade 1 were embolized. The mean cardiac cycle in which bubbles were first seen in the left heart in patients without and with PAVMs on CT was 6.1 and 3.9 (p < 0.0001). Compared to saline, Gelofusine produced an overall increase in grade.Conclusions No grade 1 patients had treatable PAVMs. There is a need for improvement in the selection of patients for CT in grade 2, where less than half have PAVMs on CT. The cardiac cycle may help to differentiate between patients with and without PAVMs. Gelofusine was not better than saline for PAVM screening.This study has been supported by grants from Instituto de Salud Carlos III (ISCIII; PI11/0246 to JAP), FEDER (to JAP), Ministerio de Economía y Competitividad of Spain (SAF2011-23475 to LMB and SAF2013-43421-R to CB), and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER; ISCIIICB06/ 07/0038 to CB).Peer reviewe

MMP-12, Secreted by Pro-Inflammatory Macrophages, Targets Endoglin in Human Macrophages and Endothelial Cells

Upon inflammation, monocyte-derived macrophages (MF) infiltrate blood vessels to regulate several processes involved in vascular pathophysiology. However, little is known about the mediators involved. Macrophage polarization is crucial for a fast and e cient initial response (GM-MF) and a good resolution (M-MF) of the inflammatory process. The functional activity of polarized MF is exerted mainly through their secretome, which can target other cell types, including endothelial cells. Endoglin (CD105) is a cell surface receptor expressed by endothelial cells and MF that is markedly upregulated in inflammation and critically involved in angiogenesis. In addition, a soluble form of endoglin with anti-angiogenic activity has been described in inflammation-associated pathologies. The aim of this work was to identify components of the MF secretome involved in the shedding of soluble endoglin. We find that the GM-MF secretome contains metalloprotease 12 (MMP-12), a GM-MF specific marker that may account for the anti-angiogenic activity of the GM-MF secretome. Cell surface endoglin is present in both GM-MF and M-MF, but soluble endoglin is only detected in GM-MF culture supernatants. Moreover, MMP-12 is responsible for the shedding of soluble endoglin in vitro and in vivo by targeting membrane-bound endoglin in both MF and endothelial cells. These data demonstrate a direct correlation between GM-MF polarization, MMP-12, and soluble endoglin expression and function. By targeting endothelial cells, MMP-12 may represent a novel mediator involved in vascular homeostasis.Ministerio de Ciencia, Innovación y Universidades of Spain (SAF2013-43421-R to C.B.; SAF2017-83785-R and SAF2014-23801 to A.L.C.)Consejo Superior de Investigaciones Cientificas (201920E022 to C.B.)Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER; ISCIII-CB06/07/0038 to C.B.)Czech Republic Specific University Research (SVV-260414 to P.N.)CIBERER is an initiative of the Instituto de Salud Carlos III (ISCIII) of Spain supported by FEDER fundsM.A. was funded with a fellowship from Ministerio de Ciencia e Innovación (BES-2008-003888)M.V. was supported by a short-term mobility fellowship from the European Erasmus Programm

Characterization of the human Activin-A receptor type II-like kinase 1 (ACVRL1) promoter and its regulation by Sp1

<p>Abstract</p> <p>Background</p> <p>Activin receptor-like kinase 1 (ALK1) is a Transforming Growth Factor-β (TGF-β) receptor type I, mainly expressed in endothelial cells that plays a pivotal role in vascular remodelling and angiogenesis. Mutations in the ALK1 gene (<it>ACVRL1</it>) give rise to Hereditary Haemorrhagic Telangiectasia, a dominant autosomal vascular dysplasia caused by a haploinsufficiency mechanism. In spite of its patho-physiological relevance, little is known about the transcriptional regulation of <it>ACVRL1</it>. Here, we have studied the different origins of <it>ACVRL1 </it>transcription, we have analyzed <it>in silico </it>its 5'-proximal promoter sequence and we have characterized the role of Sp1 in the transcriptional regulation of <it>ACVRL1</it>.</p> <p>Results</p> <p>We have performed a 5'Rapid Amplification of cDNA Ends (5'RACE) of <it>ACVRL1 </it>transcripts, finding two new transcriptional origins, upstream of the one previously described, that give rise to a new exon undiscovered to date. The 5'-proximal promoter region of <it>ACVRL1 </it>(-1,035/+210) was analyzed <it>in silico</it>, finding that it lacks TATA/CAAT boxes, but contains a remarkably high number of GC-rich Sp1 consensus sites. In cells lacking Sp1, <it>ACVRL1 </it>promoter reporters did not present any significant transcriptional activity, whereas increasing concentrations of Sp1 triggered a dose-dependent stimulation of its transcription. Moreover, silencing Sp1 in HEK293T cells resulted in a marked decrease of <it>ACVRL1 </it>transcriptional activity. Chromatin immunoprecipitation assays demonstrated multiple Sp1 binding sites along the proximal promoter region of <it>ACVRL1 </it>in endothelial cells. Furthermore, demethylation of CpG islands, led to an increase in <it>ACVRL1 </it>transcription, whereas <it>in vitro </it>hypermethylation resulted in the abolishment of Sp1-dependent transcriptional activation of <it>ACVRL1</it>.</p> <p>Conclusions</p> <p>Our results describe two new transcriptional start sites in <it>ACVRL1 </it>gene, and indicate that Sp1 is a key regulator of <it>ACVRL1 </it>transcription, providing new insights into the molecular mechanisms that contribute to the expression of <it>ACVRL1 </it>gene. Moreover, our data show that the methylation status of CpG islands markedly modulates the Sp1 regulation of <it>ACVRL1 </it>gene transcriptional activity.</p