Project description:Choroidal neovascularization (CNV) and the resulting retinal angiogenesis are pathological hallmarks of wet Age-related macular degeneration (AMD). The pathogenesis of CNV is not fully understood, but accumulated evidence has suggested the role of inflammation in the early stage of CNV. To better understand the molecular landscape during the early stage, we performed RNA-Seq and mass spectrometry-based proteomic analysis in the retina of the laser-induced CNV mouse model. Both transcriptomic and proteomic data showed dramatic activation of inflammatory response 3 days post photocoagulation. Integrative analysis suggested a moderate correlation between RNA-Seq and mass spec. Up-regulation of angiogenic factor, basic fibroblast growth factor-2 (Fgf-2), but not vascular endothelial growth factor (Vegf) was observed at both RNA and protein levels, highlighting Fgf-2 as a biomarker and potential therapeutic target during the early stage of CNV. In addition, enrichment analysis indicated a large overlap of inflammation-related genes and pathways at both levels. We also compared our findings with human retinal RNA-Seq data from AMD patients and controls. By using a multi-omics and comparative approach, our findings demonstrate the molecular landscape during the inflammatory stage of mouse CNV and provided new insight into the translation from the mouse model to understanding human AMD and its potential intervention and therapies.
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:Angiogenesis, the growth of new blood vessels from pre-existing vasculature, is essential for the development of new organ systems, but transcriptional control of angiogenesis remains incompletely understood. Here we report that FOXC1 is essential for retinal angiogenesis. Endothelial cell (EC)-specific loss of Foxc1 impairs retinal vascular growth and expression of Slc3a2 and Slc7a5, which encode the heterodimeric CD98 (LAT1/4F2hc) amino acid transporter and regulate the intracellular transport of essential amino acids and activation of the mammalian target of rapamycin (mTOR). EC-Foxc1 deficiency diminishes mTOR activity, while administration of the mTOR agonist MHY-1485 rescues perturbed retinal angiogenesis. EC-Foxc1 expression is required for retinal revascularization and resolution of neovascular tufts in a model of oxygen-induced retinopathy. Foxc1 is also indispensable for pericytes, a critical component of the blood-retina barrier during retinal angiogenesis. Our findings establish FOXC1 as a crucial regulator of retinal vessels and identify therapeutic targets for treating retinal vascular disease.
Project description:Blood vessel growth and remodelling are essential during embryonic development and disease pathogenesis. The diversity of endothelial cells (ECs) is transcriptionally evident and ECs undergo dynamic changes in gene expression during vessel growth and remodelling.Here, we investigated the role of the histone acetyltransferase HBO1 (KAT7), which is important for activating genes during development and histone H3 lysine 14 acetylation (H3K14ac). Loss of HBO1 and H3K14ac impaired developmental sprouting angiogenesis and reduced pathological EC overgrowth in the retinal endothelium. Single-cell RNA-sequencing of retinal ECs revealed an increased abundance of tip cells in Hbo1 deleted retinas, which lead to EC overcrowding in the retinal sprouting front and prevented efficient tip cell migration. We found that H3K14ac was highly abundant in the endothelial genome in both intra- and intergenic regions suggesting that the role of HBO1 is as a genome organiser that promotes efficient tip cell behaviour necessary for sprouting angiogenesis.
Project description:Angiogenesis, a process mediating the expansion of vascular beds in many physiological and pathological settings, requires dynamic changes in endothelial cell (EC) behavior. The molecular mechanisms governing EC activity during different phases of vascular growth, remodeling, maturation, and quiescence remain elusive. Here, we have employed actively translating transcriptome analysis of mouse retinal ECs for the characterization of dynamic gene expression changes during postnatal development and the identification of critical angiogenic factors.
Project description:In the developing retina, as in many other regions of the central nervous system, multipotent neural progenitor cells undergo unidirectional changes to produce differentiated cells in a precise spatiotemporal order. Here we profile the epigenetic and transcriptional changes that occur during retinal development in mice and humans. Although some progenitor genes and cell cycle genes were epigenetically silenced during retinogenesis, the most dramatic change was derepression of cell type–specific differentiation programs. We identified developmental stage–specific superenhancers and showed that the majority of epigenetic changes during murine retinal development are conserved in the human retina. To determine how the epigenome changes during tumorigenesis and reprogramming, we performed the same integrated epigenetic analysis of murine and human retinoblastomas and iPSCs derived from murine rod photoreceptors. The retinoblastoma epigenome mapped to the developmental stage when retinal progenitors switch from a neurogenic to a terminal pattern of cell division and murine retinoblastomas initiate earlier in development than human tumors. The epigenome of retinoblastomas was far more similar to that of normal retina than was the epigenome of retinal-derived iPSCs but we were able to identify retinal specific epigenetic memory. Together, these data provide an in depth view of the dynamic epigenome during neurogenesis and how that relates to developmental tumors and epigenetic memory in iPSCs produced from neurons.
Project description:In the developing retina, as in many other regions of the central nervous system, multipotent neural progenitor cells undergo unidirectional changes to produce differentiated cells in a precise spatiotemporal order. Here we profile the epigenetic and transcriptional changes that occur during retinal development in mice and humans. Although some progenitor genes and cell cycle genes were epigenetically silenced during retinogenesis, the most dramatic change was derepression of cell type–specific differentiation programs. We identified developmental stage–specific superenhancers and showed that the majority of epigenetic changes during murine retinal development are conserved in the human retina. To determine how the epigenome changes during tumorigenesis and reprogramming, we performed the same integrated epigenetic analysis of murine and human retinoblastomas and iPSCs derived from murine rod photoreceptors. The retinoblastoma epigenome mapped to the developmental stage when retinal progenitors switch from a neurogenic to a terminal pattern of cell division and murine retinoblastomas initiate earlier in development than human tumors. The epigenome of retinoblastomas was far more similar to that of normal retina than was the epigenome of retinal-derived iPSCs but we were able to identify retinal specific epigenetic memory. Together, these data provide an in depth view of the dynamic epigenome during neurogenesis and how that relates to developmental tumors and epigenetic memory in iPSCs produced from neurons.
Project description:In the developing retina, as in many other regions of the central nervous system, multipotent neural progenitor cells undergo unidirectional changes to produce differentiated cells in a precise spatiotemporal order. Here we profile the epigenetic and transcriptional changes that occur during retinal development in mice and humans. Although some progenitor genes and cell cycle genes were epigenetically silenced during retinogenesis, the most dramatic change was derepression of cell type–specific differentiation programs. We identified developmental stage–specific superenhancers and showed that the majority of epigenetic changes during murine retinal development are conserved in the human retina. To determine how the epigenome changes during tumorigenesis and reprogramming, we performed the same integrated epigenetic analysis of murine and human retinoblastomas and iPSCs derived from murine rod photoreceptors. The retinoblastoma epigenome mapped to the developmental stage when retinal progenitors switch from a neurogenic to a terminal pattern of cell division and murine retinoblastomas initiate earlier in development than human tumors. The epigenome of retinoblastomas was far more similar to that of normal retina than was the epigenome of retinal-derived iPSCs but we were able to identify retinal specific epigenetic memory. Together, these data provide an in depth view of the dynamic epigenome during neurogenesis and how that relates to developmental tumors and epigenetic memory in iPSCs produced from neurons.
Project description:Interactions among neuroglial and vascular components are crucial for retinal angiogenesis and blood-retinal barrier (BRB) maturation. Neuronal synaptic dysfunctions precede vascular abnormalities in many retinal pathologies. However, whether neuronal activity, specifically glutamatergic activity, regulates retinal angiogenesis and BRB maturation remains unclear. Using in vivo genetic studies in mice, single-cell RNA-sequencing and functional validation, we found that deep plexus angiogenesis and paracellular BRB maturation are delayed in Vglut1-/- retinas, where neurons fail to release glutamate. In contrast, deep plexus angiogenesis and paracellular BRB maturation are accelerated in Gnat1-/- retinas, where constitutively depolarized rods release excess glutamate. Mechanistically, Norrin expression and endothelial Norrin/b-catenin signaling are downregulated in Vglut1-/- retinas, and upregulated in Gnat1-/- retinas. Pharmacological activation of endothelial Norrin/ b-catenin signaling in Vglut1-/- retinas rescued both deep plexus angiogenesis and paracellular BRB integrity. Thus, our findings demonstrate that glutamatergic neuronal activity regulates retinal angiogenesis and BRB maturation by modulating Norrin/b-catenin signaling.