title: Discoidin domain receptor 1 mediates collagen-induced inflammatory activation of microglia in culture.
abstract: Discoidin domain receptor 1 (DDR1) is a nonintegrin collagen receptor tyrosine kinase with an extracellular domain homologous to discoidin 1 of a soil-living amoeba Dictyostelium discoideum. We have previously demonstrated that DDR1 mediates collagen-induced nitric oxide production in J774A.1 murine macrophages. Because collagen is one of the main components of extracellular matrix in the central nervous system, we hypothesized that collagen also induces inflammatory activation of brain microglia, and DDR1 may mediate collagen-induced microglial activation. Using BV-2 mouse microglial cells and mouse primary microglial cultures, we have demonstrated that (1) collagen induces inflammatory activation of microglia as evidenced by production of nitric oxide, expression of inducible nitric oxide synthase, COX-2, CD40, and matrix metalloproteinase-9; (2) DDR1 is expressed in microglia and is phosphorylated by collagen treatment; and (3) collagen-induced microglial activation is abrogated by DDR1 blockade but not by integrin neutralization. We have further shown that p38 MAPK, c-Jun N-terminal kinase, and nuclear factor-kappa B are involved in the collagen-DDR1-induced microglial activation. Our results suggest that collagen can induce inflammatory activation of brain microglia and that DDR1 mediates this effect of collagen in an integrin-independent manner.
authors.affiliation: Department of Pharmacology, Brain Science and Engineering Institute, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Min-Chul
authors.initials: MC
authors.lastname: Seo
authors.forename: Sangseop
authors.initials: S
authors.lastname: Kim
authors.forename: Sang-Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Long Tai
authors.initials: LT
authors.lastname: Zheng
authors.forename: Eui Kyun
authors.initials: EK
authors.lastname: Park
authors.forename: Won-Ha
authors.initials: WH
authors.lastname: Lee
authors.forename: Kyoungho
authors.initials: K
authors.lastname: Suk
mesh_terms: D000818:Animals; D019013:CD40 Antigens / Q000378:metabolism; D002460:Cell Line; D003094:Collagen / Q000378:metabolism* / Q000494:pharmacology; D051546:Cyclooxygenase 2 / Q000378:metabolism; D000070818:Discoidin Domain Receptors; D004660:Encephalitis / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005911:Gliosis / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology; D016023:Integrins / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051379:Mice; D017628:Microglia / Q000187:drug effects / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis; D020794:Receptor Protein-Tyrosine Kinases / Q000187:drug effects / Q000378:metabolism*; D011975:Receptors, Mitogen / Q000187:drug effects / Q000378:metabolism*
chemical_list: D019013:CD40 Antigens; D016326:Extracellular Matrix Proteins; D016023:Integrins; D016328:NF-kappa B; D011975:Receptors, Mitogen; D009569:Nitric Oxide; D003094:Collagen; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D000070818:Discoidin Domain Receptors; D020794:Receptor Protein-Tyrosine Kinases; D020780:Matrix Metalloproteinase 9