This SuperSeries is composed of the SubSeries listed below.
Endothelial GATA4 controls liver fibrosis and regeneration by preventing a pathogenic switch in angiocrine signaling.
Specimen part, Treatment
View SamplesLiver sinusoidal endothelial cells (LSEC) constitute discontinuous, permeable microvessels, with a characteristic program of gene expression that differs significantly from continuous microvascular endothelial cells e.g. in the lung. Gata4 is described as master regulator of LSEC specification during liver development. Here, we sought to analyze the role of endothelial Gata4 in the adult liver.
Endothelial GATA4 controls liver fibrosis and regeneration by preventing a pathogenic switch in angiocrine signaling.
Specimen part
View SamplesLiver sinusoidal endothelial cells (LSEC) constitute discontinuous, permeable microvessels, with a characteristic program of gene expression that differs significantly from continuous microvascular endothelial cells e.g. in the lung. LSEC play a pivotal role in liver fibrogenesis in the CDAA dietary model of non-alcoholic steatohepatitis (NASH).
Endothelial GATA4 controls liver fibrosis and regeneration by preventing a pathogenic switch in angiocrine signaling.
Specimen part, Treatment
View SamplesLiver sinusoidal endothelial cells (LSEC) constitute discontinuous, permeable microvessels, with a characteristic program of gene expression that differs significantly from continuous microvascular endothelial cells e.g. in the lung. Gata4 is described as master regulator of LSEC specification during liver development. Here, we sought to analyze the role of endothelial Gata4 in the adult liver.
Endothelial GATA4 controls liver fibrosis and regeneration by preventing a pathogenic switch in angiocrine signaling.
Specimen part
View SamplesAdult BALB/c female mice were injected intraperitoneally with a single dose at 20 mg per kg of antisense oligonucleotide either against miR-29a (5-TAACCGATTTCAGATGGTGCTA-3) or against a scrambled sequence (5-TCATTGGCATGTACCATGCAGCT-3 Antisense oligonucleotides contained 2-O-methoxyethyl (2-MOE), 2-flouro (2-F) 2'-alpha-flouro units with a phosphorothioate backbone (Regulus Therapeutics). Six days following the injection, liver was isolated, total RNA was prepared as described above, and the RNA was amplified and biotinylated using the MessageAmp Premier kit (Ambion). Samples (n=4 each experimental and control) were hybridized to Affymetrix GeneChip Mouse Genome 430 2.0 Arrays in the Childrens Hospital of Philadelphia Nucleic Acids Core Facilityand analyzed with the assistance of the Penn Bioinformatics Core. Probe intensities were normalized using the GCRMA method and the significance of the log2-transformed, GCRMA-normalized signal intensities was determined using SAM
MicroRNA profiling identifies miR-29 as a regulator of disease-associated pathways in experimental biliary atresia.
Sex, Specimen part, Treatment
View SamplesSoluble VEGFR-1 (sVEGFR-1) acts both as a decoy receptor for VEGFs and as an extracellular matrix protein for 51 integrin. A sVEGFR-1-derived peptide that interacts with 51 integrin promotes angiogenesis. However, canonical signal downstream integrin activation is not induced, resulting into lack of focal adhesion maturation. We performed a gene expression profile of endothelial cells adhering on sVEGFR-1 compared to that of cells adhering on fibronectin, the principal 51 integrin ligand. Three protein kinase-C substrates, adducin, MARCKS, and radixin were differently modulated. Adducin and MARCKS were less phosphorylated whereas radixin was higher phosphorylated in sVEGFR-1 adhering cells, the latter leading to prolonged small GTPase Rac1 activation and induction of a pathway involving the heterotrimeric G protein 13. Altogether, our data indicated endothelial cell acquisition of an highly motile phenotype when adherent on sVEGFR-1. Finally, we indicated radixin as accountable for the angiogenic effect of 51 integrin interaction with sVEGFR-1 that in turn depends on an active VEGF-A/VEGFR-2 signaling.
Endothelial cell adhesion to soluble vascular endothelial growth factor receptor-1 triggers a cell dynamic and angiogenic phenotype.
Specimen part
View SamplesRecessive dystrophic epidermolysis bullosa (RDEB) is a genodermatosis characterized by fragile skin forming blisters that heal invariably with scars. It is due to mutations in the COL7A1 gene encoding type VII collagen, the major component of anchoring fibrils connecting the cutaneous basement membrane to the dermis. Identical COL7A1 mutations often result in inter- and intra-familial disease variability, suggesting that additional modifiers contribute to RDEB course. Here, we studied a monozygotic twin pair with RDEB presenting markedly different phenotypic manifestations, while expressing similar amounts of collagen VII. Genome-wide expression analysis in twins' fibroblasts showed differential expression of genes associated with TGF- pathway inhibition. In particular, decorin, a skin matrix component with anti-fibrotic properties, was found to be more expressed in the less affected twin. Accordingly, fibroblasts from the more affected sibling manifested a profibrotic and contractile phenotype characterized by enhanced -smooth muscle actin and plasminogen activator inhibitor 1 expression, collagen I release and collagen lattice contraction. These cells also produced increased amounts of proinflammatory cytokines interleukin 6 and monocyte chemoattractant protein-1. Both TGF- canonical (Smads) and non-canonical (MAPKs) pathways were basally more activated in the fibroblasts of the more affected twin. The profibrotic behaviour of these fibroblasts was suppressed by decorin delivery to cells. Our data show that the amount of type VII collagen is not the only determinant of RDEB clinical severity, and indicate an involvement of TGF- pathways in modulating disease variability. Moreover, our findings identify decorin as a possible anti-fibrotic/inflammatory agent for RDEB therapeutic intervention.
Monozygotic twins discordant for recessive dystrophic epidermolysis bullosa phenotype highlight the role of TGF-β signalling in modifying disease severity.
Specimen part, Disease
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