title: Implication of matrix metalloproteinases 2 and 9 in ceramide 1-phosphate-stimulated macrophage migration.
abstract: Cell migration is a complex biological function involved in both physiologic and pathologic processes. Although this is a subject of intense investigation, the mechanisms by which cell migration is regulated are not completely understood. In this study we show that the bioactive sphingolipid ceramide 1-phosphate (C1P), which is involved in inflammatory responses, causes upregulation of metalloproteinases (MMP) -2 and -9 in J774A.1 macrophages. This effect was shown to be dependent on stimulation of phosphatidylinositol 3-kinase (PI3K) and extracellularly regulated kinases 1-2 (ERK1-2) as demonstrated by treating the cells with specific siRNA to knockdown the p85 regulatory subunit of PI3K, or ERK1-2. Inhibition of MMP-2 or MMP-9 pharmacologically or with specific siRNA to silence the genes encoding these MMPs abrogated C1P-stimulated macrophage migration. Also, C1P induced actin polymerization and potently increased phosphorylation of the focal adhesion protein paxillin, which are essential factors in the regulation of cell migration. As expected, blockade of paxillin activation with specific siRNA significantly reduced actin polymerization. In addition, inhibition of actin polymerization with cytochalasin D completely blocked C1P-induced MMP-2 and -9 expression as well as C1P-stimulated macrophage migration. It was also observed that pertussis toxin (Ptx) inhibited Akt, ERK1-2, and paxillin phosphorylation, and completely blocked cell migration. The latter findings support the notion that C1P-stimulated macrophage migration is a receptor mediated effect, and point to MMP-2 and -9 as possible therapeutic targets to control inflammation.
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Ordoñez
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain.
authors.forename: Io-Guané
authors.initials: IG
authors.lastname: Rivera
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain.
authors.forename: Natalia
authors.initials: N
authors.lastname: Presa
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain. Electronic address: antonio.gomez@ehu.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Gomez-Muñoz
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects*; D002518:Ceramides / Q000494:pharmacology*; D015638:Cytochalasin D / Q000494:pharmacology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000378:metabolism; D008264:Macrophages / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D051379:Mice; D051419:Paxillin / Q000378:metabolism; D037342:Pertussis Toxin / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D058105:Polymerization / Q000187:drug effects; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism
chemical_list: D000199:Actins; D002518:Ceramides; D051419:Paxillin; D043562:Receptors, G-Protein-Coupled; C065576:ceramide 1-phosphate; D015638:Cytochalasin D; D037342:Pertussis Toxin; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D019206:GTP-Binding Protein alpha Subunits, Gi-Go
keywords: Cell migration; Ceramide 1-phosphate; Ceramide kinase; Ceramides; Matrix metalloproteinases; Sphingolipids