title: Neural deletion of Tgfbr2 impairs angiogenesis through an altered secretome.
abstract: Simultaneous generation of neural cells and that of the nutrient-supplying vasculature during brain development is called neurovascular coupling. We report on a transgenic mouse with impaired transforming growth factor β (TGFβ)-signalling in forebrain-derived neural cells using a Foxg1-cre knock-in to drive the conditional knock-out of the Tgfbr2. Although the expression of FOXG1 is assigned to neural progenitors and neurons of the telencephalon, Foxg1(cre/+);Tgfbr2(flox/flox) (Tgfbr2-cKO) mutants displayed intracerebral haemorrhage. Blood vessels exhibited an atypical, clustered appearance were less in number and displayed reduced branching. Vascular endothelial growth factor (VEGF) A, insulin-like growth factor (IGF) 1, IGF2, TGFβ, inhibitor of DNA binding (ID) 1, thrombospondin (THBS) 2, and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) 1 were altered in either expression levels or tissue distribution. Accordingly, human umbilical vein endothelial cells (HUVEC) displayed branching defects after stimulation with conditioned medium (CM) that was derived from primary neural cultures of the ventral and dorsal telencephalon of Tgfbr2-cKO. Supplementing CM of Tgfbr2-cKO with VEGFA rescued these defects, but application of TGFβ aggravated them. HUVEC showed reduced migration towards CM of mutants compared with controls. Supplementing the CM with growth factors VEGFA, fibroblast growth factor (FGF) 2 and IGF1 partially restored HUVEC migration. In contrast, TGFβ supplementation further impaired migration of HUVEC. We observed differences along the dorso-ventral axis of the telencephalon with regard to the impact of these factors on the phenotype. Together these data establish a TGFBR2-dependent molecular crosstalk between neural and endothelial cells during brain vessel development. These findings will be useful to further elucidate neurovascular interaction in general and to understand pathologies of the blood vessel system such as intracerebral haemorrhages, hereditary haemorrhagic telangiectasia, Alzheimeŕs disease, cerebral amyloid angiopathy or tumour biology.
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Hellbach
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Stefan C
authors.initials: SC
authors.lastname: Weise
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Vezzali
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Shalaka D
authors.initials: SD
authors.lastname: Wahane
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Heidrich
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Deborah
authors.initials: D
authors.lastname: Roidl
authors.affiliation: Emmy Noether-Group for Stem Cell Biology, Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany, Center for Biological Signaling Studies (BIOSS), University of Freiburg, 79104 Freiburg, Germany and.
authors.forename: Jan
authors.initials: J
authors.lastname: Pruszak
authors.affiliation: Department of Cardiology and Angiology I, University Heart Center Freiburg, 79106 Freiburg, Germany.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Esser
authors.affiliation: Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 79104 Freiburg, Germany, tanja.vogel@anat.uni-freiburg.de.
authors.forename: Tanja
authors.initials: T
authors.lastname: Vogel
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000378:metabolism; D001921:Brain / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D002465:Cell Movement; D002543:Cerebral Hemorrhage / Q000378:metabolism / Q000473:pathology; D017077:Culture Media, Conditioned; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D018919:Neovascularization, Physiologic; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D058953:Neural Stem Cells / Q000378:metabolism / Q000473:pathology; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D020286:Pericytes / Q000378:metabolism / Q000473:pathology; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000235:genetics* / Q000378:metabolism; D055571:Secretory Pathway; D013687:Telencephalon / Q000098:blood supply / Q000378:metabolism / Q000473:pathology; D016212:Transforming Growth Factor beta / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D017077:Culture Media, Conditioned; D051858:Forkhead Transcription Factors; C489565:Foxg1 protein, mouse; D009419:Nerve Tissue Proteins; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; D016222:Fibroblast Growth Factor 2; D007334:Insulin-Like Growth Factor I; D017346:Protein Serine-Threonine Kinases; D000077294:Receptor, Transforming Growth Factor-beta Type II