ABSTRACT: Reduced Retinal Microvascular Density, Improvement in Forepaw Reach, Comparative Microarray and Gene Set Enrichment Analysis using DNA Enzyme Targeting c-jun mRNA
Project description:Retinal neovascularization is a critical component in the pathogenesis of common ocular disorders that cause blindness, and treatment options are limited. We evaluated the therapeutic effect of a DNA enzyme targeting c-jun mRNA in mice with pre-existing retinal neovascularization. A single injection of Dz13 in a lipid formulation containing N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium methyl-sulfate and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine inhibited c-Jun expression and reduced retinal microvascular density. The DNAzyme inhibited retinal microvascular density as effectively as VEGF-A antibodies. Comparative microarray and gene expression analysis determined that Dz13 suppressed not only c-jun but a range of growth factors and matrix-degrading enzymes. Dz13 in this formulation inhibited microvascular endothelial cell proliferation, migration and tubule formation in vitro. Moreover, animals treated with Dz13 sensed the top of the cage in a modified forepaw reach model, unlike mice given a DNAzyme with scrambled RNA-binding arms that did not affect c-Jun expression. These findings demonstrate reduction of microvascular density and improvement in forepaw reach in mice administered catalytic DNA. Total RNA from pooled eyes was used to prepare labeled probes for microarrays. Pooled samples included a Control, Vehicle, Dz13 and Dz13_scrambled.
Project description:Retinal neovascularization is a critical component in the pathogenesis of common ocular disorders that cause blindness, and treatment options are limited. We evaluated the therapeutic effect of a DNA enzyme targeting c-jun mRNA in mice with pre-existing retinal neovascularization. A single injection of Dz13 in a lipid formulation containing N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium methyl-sulfate and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine inhibited c-Jun expression and reduced retinal microvascular density. The DNAzyme inhibited retinal microvascular density as effectively as VEGF-A antibodies. Comparative microarray and gene expression analysis determined that Dz13 suppressed not only c-jun but a range of growth factors and matrix-degrading enzymes. Dz13 in this formulation inhibited microvascular endothelial cell proliferation, migration and tubule formation in vitro. Moreover, animals treated with Dz13 sensed the top of the cage in a modified forepaw reach model, unlike mice given a DNAzyme with scrambled RNA-binding arms that did not affect c-Jun expression. These findings demonstrate reduction of microvascular density and improvement in forepaw reach in mice administered catalytic DNA.
Project description:Retinal microvascularization can provide important informations to systemic vascular phenomena. The non-invasive quantitative description of the retinal vascularization is now possible by performing OCT-angiography and their image analysis software (vascular density and retinal perfusion). Systemic microvacular changes during the establishment of oncological treatment by targeted antiangiogenic therapy are little described in the literature. The objective of this pilot study is to describe the evolution of the retinal vascular density of patients with antiangiogenic drugs. In addition, the evolution of the retinal vascular density of patients on antiangiogenic drugs will study as a function of the response to the treatment and the toxicity of these treatments.
Project description:Iron induces hepcidin by activating bone morphogenetic protein (BMP)6-SMAD signaling. Liver endothelial cells (LECs) produce BMP6, but the molecular mechanisms are incompletely understood. To address this, we performed proteomics and RNA-sequencing on LECs from iron-adequate and iron-loaded mice. Gene set enrichment analysis identified transcription factors activated by high iron, including Nrf-2, which was previously reported to contribute to BMP6 regulation, and proto-oncogene c-Jun (encoded by Jun). Jun knockdown blocked Bmp6, but not Nrf-2 pathway, induction by iron in LEC cultures. Moreover, chromatin immunoprecipitation of mouse livers showed iron-dependent c-Jun binding to predicted sites in Bmp6 regulatory regions. Finally, c-Jun inhibitor blunted induction of Bmp6 and hepcidin, but not Nrf-2 activity, in iron-loaded mice. However, Bmp6 expression and iron parameters were unchanged in endothelial Jun knockout mice. Our data suggest that c-Jun participates in iron-mediated BMP6 regulation independent of Nrf-2, though the mechanisms may be redundant and/or multifactorial.
Project description:To compare the gene expression profiles of unpassaged, proliferating HUVEC and human iris, retinal and choroidal microvascular endothelial cells. Gene expression profiling revealed significant differences between HUVEC and ocular microvascular endothelial cells suggesting that HUVE cells may not be a suitable surrogate when studying pathophysiological mechanisms of ocular disorders. There were significant differences in the gene expression of important cell signalling pathways in human retinal and choroidal ECs. These differences may be important in the mechanisms and treatment of choroidal and retinal neovascularisation. 12 arrays are included. Endothelial cells were derived from 4 tissues: iris, retina, choroid and human umbilical vein. RNA extracts from cells were hybridised to Affymetrix HGU133plus2 arrays in triplicate.
Project description:To compare the gene expression profiles of unpassaged, proliferating HUVEC and human iris, retinal and choroidal microvascular endothelial cells. Gene expression profiling revealed significant differences between HUVEC and ocular microvascular endothelial cells suggesting that HUVE cells may not be a suitable surrogate when studying pathophysiological mechanisms of ocular disorders. There were significant differences in the gene expression of important cell signalling pathways in human retinal and choroidal ECs. These differences may be important in the mechanisms and treatment of choroidal and retinal neovascularisation.
Project description:The goal of this study is to investigate the role of TET enzyme-mediated DNA demethylation on retinal development and cell fate specification. We utilized an allelic series of TET enzyme retinal conditional mouse mutants using the Chx10-Cre-GFP transgene, removing the TET enzymes from retinal progenitor cells. We observe that inhibition of DNA demethylation results in abnormal retinal development and a loss of visual function. As human retinoblastoma displays reduced TET3 protein expression and a reduction in 5hmC similar to our TET mutant models, we compare the RNA expression changes across human retinoblastoma and TET mutant retinas to identify common pathways that are altered when 5hmC is lost.
