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Arechederra M.,Complutense University of Madrid | Priego N.,Complutense University of Madrid | Vazquez-Carballo A.,Complutense University of Madrid | Sequera C.,Complutense University of Madrid | And 9 more authors.
Journal of Biological Chemistry | Year: 2015

p38 MAPKs regulate migration and invasion. However, the mechanisms involved are only partially known. We had previously identified fibulin 3, which plays a role in migration, invasion, and tumorigenesis, as a gene regulated by p38α. We have characterized in detail how p38 MAPK regulates fibulin 3 expression and its role. We describe here for the first time that p38α, p38γ, and p38δ down-regulate fibulin 3 expression. p38αhas a stronger effect, and it does so through hypermethylation of CpG sites in the regulatory sequences of the gene. This would be mediated by theDNAmethylase, DNMT3A, which is down-regulated in cells lacking p38α, but once re-introduced represses Fibulin 3 expression. p38α through HuR stabilizes dnmt3a mRNA leading to an increase in DNMT3A protein levels. Moreover, by knocking-down fibulin 3, we have found that Fibulin 3 inhibits migration and invasion in MEFs by mechanisms involving p38α/β inhibition. Hence, p38α pro-migratory/invasive effect might be, at least in part, mediated by fibulin 3 down-regulation in MEFs. In contrast, in HCT116 cells, Fibulin 3 promotes migration and invasion through a mechanism dependent on p38α and/or p38β activation. Furthermore, Fibulin 3 promotes in vitro and in vivo tumor growth of HCT116 cells through a mechanism dependent on p38α, which surprisingly acts as a potent inducer of tumor growth. At the same time, p38α limits fibulin 3 expression, which might represent a negative feed-back loop. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc. Source

Rossi E.,CSIC - Biological Research Center | Rossi E.,Research Center Biomedica En Red Of Enfermedades Raras Ciberer | Rossi E.,University of Paris Descartes | Smadja D.M.,AP HP | And 22 more authors.
Cellular and Molecular Life Sciences | Year: 2015

The circulatory system is walled off by different cell types, including vascular mural cells and podocytes. The interaction and interplay between endothelial cells (ECs) and mural cells, such as vascular smooth muscle cells or pericytes, play a pivotal role in vascular biology. Endoglin is an RGD-containing counter-receptor for β1 integrins and is highly expressed by ECs during angiogenesis. We find that the adhesion between vascular ECs and mural cells is enhanced by integrin activators and inhibited upon suppression of membrane endoglin or β1-integrin, as well as by addition of soluble endoglin (SolEng), anti-integrin α5β1 antibody or an RGD peptide. Analysis of different endoglin mutants, allowed the mapping of the endoglin RGD motif as involved in the adhesion process. In Eng+/− mice, a model for hereditary hemorrhagic telangectasia type 1, endoglin haploinsufficiency induces a pericyte-dependent increase in vascular permeability. Also, transgenic mice overexpressing SolEng, an animal model for preeclampsia, show podocyturia, suggesting that SolEng is responsible for podocytes detachment from glomerular capillaries. These results suggest a critical role for endoglin in integrin-mediated adhesion of mural cells and provide a better understanding on the mechanisms of vessel maturation in normal physiology as well as in pathologies such as preeclampsia or hereditary hemorrhagic telangiectasia. © 2015 The Author(s) Source

Rodriguez-Pena A.B.,Instituto Reina Sofia Of Investigacion Nefrologica | Rodriguez-Pena A.B.,University of Salamanca | Fuentes-Calvo I.,Instituto Reina Sofia Of Investigacion Nefrologica | Docherty N.G.,Instituto Reina Sofia Of Investigacion Nefrologica | And 11 more authors.
BioMed Research International | Year: 2014

Tubulointerstitial fibrosis is a major feature of chronic kidney disease. Unilateral ureteral obstruction (UUO) in rodents leads to the development of renal tubulointerstitial fibrosis consistent with histopathological changes observed in advanced chronic kidney disease in humans. The purpose of this study was to assess the effect of inhibiting angiotensin II receptors or Ras activation on early renal fibrotic changes induced by UUO. Animals either received angiotensin II or underwent UUO. UUO animals received either losartan, atorvastatin, and farnesyl transferase inhibitor (FTI) L-744,832, or chaetomellic acid A (ChA). Levels of activated Ras, phospho-ERK1/2, phospho-Akt, fibronectin, and α-smooth muscle actin were subsequently quantified in renal tissue by ELISA, Western blot, and/or immunohistochemistry. Our results demonstrate that administration of angiotensin II induces activation of the small GTPase Ras/Erk/Akt signaling system, suggesting an involvement of angiotensin II in the early obstruction-induced activation of renal Ras. Furthermore, upstream inhibition of Ras signalling by blocking either angiotensin AT1 type receptor or by inhibiting Ras prenylation (atorvastatin, FTI o ChA) reduced the activation of the Ras/Erk/Akt signaling system and decreased the early fibrotic response in the obstructed kidney. This study points out that pharmacological inhibition of Ras activation may hold promise as a future strategy in the prevention of renal fibrosis. © 2014 Ana B. Rodríguez-Peña et al. Source

Aristizabal J.A.,Hospital Universitario Of Salamanca | Aristizabal J.A.,Institute Investigaciones Biomedicas Of Salamanca Ibsal | Aristizabal J.A.,University of Salamanca | Chandia M.,Hospital Universitario Of Salamanca | And 8 more authors.
Revista Medica de Chile | Year: 2014

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm related to the presence of the BCR-ABL1 fusion gene, linked to t (9;22) (q34;q11). It is originated from an abnormal hematopoietic stem cell, which is characterized as its normal counterparts by long-term self-renewal and multi-lineage differentiation. Both leukemic and quiescent normal hematopoietic stem cells preferentially reside in the osteoblastic niche. Mesenchymal stromal cells (MSC) are located near them, playing a critical role in their regulation. Currently, with tyrosine kinase inhibitor (TKI) therapy, long term clinical responses are achieved in most CML cases. However, late treatment failures may be observed related to the persistence of leukemic stem cells. The interactions between the leukemic stem cell and the microenvironment may be responsible in part for these events. We review the interactions between the leukemic stem cell and BM stroma and its potential clinical and therapeutic implications. Source

Villar L.P.D.,University of Salamanca | Villar L.P.D.,Institute Investigaciones Biomedicas Of Salamanca Ibsal | Vicente B.,University of Salamanca | Vicente B.,Institute Investigaciones Biomedicas Of Salamanca Ibsal | And 7 more authors.
Parasite | Year: 2013

Most Schistosoma mansoni experimental infections are developed in several inbred strains of Mus musculus as definitive host. In contrast, Mus spretus is unexplored in Schistosoma infection studies. Mus spretus provides a high variation of immunological phenotypes being an invaluable tool for genetic studies and gene mapping. The aim of this study is to characterize hematological and immunological responses against Schistosoma mansoni infection in Mus spretus (SPRET/EiJ strain) vs. Mus musculus (CD1 strain) mice. Nine weeks after cercarial exposure, animals were perfused and the parasite burden was assessed. The parasitological data suggests that SPRET/EiJ mice tolerate higher parasite loads compared to CD1 strain. In addition, hematological parameters measured in Mus spretus group showed a significant increase in granulocytes population in early stages of infection compared to the CD1 cohort. Meanwhile, CD1 presented higher levels of lymphocytes and IgG1 in the late stages of S. mansoni experimental infection. © 2013 L. Perez del Villar et al., published by EDP Sciences. Source

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