title: Osteoblasts extracellular matrix induces vessel like structures through glycosylated collagen I.
abstract: Extracellular matrix (ECM) plays a fundamental role in angiogenesis affecting endothelial cells proliferation, migration and differentiation. Vessels-like network formation in vitro is a reliable test to study the inductive effects of ECM on angiogenesis. Here we utilized matrix deposed by osteoblasts as substrate where the molecular and structural complexity of the endogenous ECM is preserved, to test if it induces vessel-like network formation by endothelial cells in vitro. ECM is more similar to the physiological substrate in vivo than other substrates previously utilized for these studies in vitro. Osteogenic ECM, prepared in vitro from mature osteoblasts at the phase of maximal deposition and glycosylation of collagen I, induces EAhy926, HUVEC, and HDMEC endothelial cells to form vessels-like structures and promotes the activation of metalloproteinase-2 (MMP-2); the functionality of the p-38/MAPK signaling pathway is required. Osteogenic ECM also induces a transient increase of CXCL12 and a decrease of the receptor CXCR4. The induction of vessel-like networks is dependent from proper glycosylation of collagens and does not occur on osteogenic ECMs if deglycosylated by -galactosidase or on less glycosylated ECMs derived from preosteoblasts and normal fibroblasts, while is sustained on ECM from osteogenesis imperfecta fibroblasts only when their mutation is associated with over-glycosylation of collagen type I. These data support that post-translational glycosylation has a role in the induction in endothelial cells in vitro of molecules conductive to self-organization in vessels-like structures.
authors.affiliation: Genetics, DIBIO, University of Genova, Corso Europa 26, 16132 Genova, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Palmieri
authors.forename: M
authors.initials: M
authors.lastname: Valli
authors.forename: S
authors.initials: S
authors.lastname: Viglio
authors.forename: N
authors.initials: N
authors.lastname: Ferrari
authors.forename: B
authors.initials: B
authors.lastname: Ledda
authors.forename: C
authors.initials: C
authors.lastname: Volta
authors.forename: P
authors.initials: P
authors.lastname: Manduca
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000235:genetics / Q000378:metabolism; D003094:Collagen / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D024042:Collagen Type I / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D017077:Culture Media, Conditioned / Q000737:chemistry; D004789:Enzyme Activation; D005109:Extracellular Matrix / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000502:physiology*; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D019718:Receptors, CXCR4 / Q000235:genetics / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: D054377:Chemokine CXCL12; D024042:Collagen Type I; D017077:Culture Media, Conditioned; D019718:Receptors, CXCR4; C022814:glycosylated collagen; D003094:Collagen; D048051:p38 Mitogen-Activated Protein Kinases; D020778:Matrix Metalloproteinase 2