title: Proteinase-activated receptor-1 regulation of macrophage elastase (MMP-12) secretion by serine proteinases.
abstract: The serine proteinases plasmin and thrombin convert proenzyme matrix metalloproteinases (MMPs) into catalytically active forms. In addition, we demonstrate that plasmin(ogen) and thrombin induce a significant increase in secretion of activated murine macrophage elastase (MMP-12) protein. Active serine protease is responsible for induction, as demonstrated by the absence of MMP-12 induction in plasminogen(Plg)-treated urokinase-type plasminogen activator-deficient macrophages. Since increased MMP-12 protein secretion was not accompanied by an increase in MMP-12 mRNA, we examined post-translational mechanisms. Protein synthesis was not required for early release of MMP-12 but was required for later secretion of activated enzyme. Immunofluorescent microscopy demonstrated basal expression in macrophages that increased following serine proteinase exposure. Inhibition of MMP-12 secretion by hirudin and pertussis toxin demonstrated a role for the thrombin G protein-coupled receptor (protease-activated receptor 1 (PAR-1)). PAR-1-activating peptides were able to induce MMP-12 release. Investigation of signal transduction pathways involved in this response demonstrate the requirement for protein kinase C, but not tyrosine kinase, activity. These data demonstrate that plasmin and thrombin regulate MMP-12 activity through distinct mechanisms: post-translational secretion of preformed MMP-12 protein, induction of protein secretion that is protein kinase C-mediated, and extracellular enzyme activation. Most importantly, we show that serine proteinase MMP-12 regulation in macrophages occurs via the protein kinase C-activating G protein-coupled receptor PAR-1.
authors.affiliation: Divisions of Dermatology and Respiratory and Critical Care, Department of Medicine, Children's Place,Washington University School of Medicine at Barnes-Jewish Hospital, St.Louis, MO 63110, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Raza
authors.forename: L C
authors.initials: LC
authors.lastname: Nehring
authors.forename: S D
authors.initials: SD
authors.lastname: Shapiro
authors.forename: L A
authors.initials: LA
authors.lastname: Cornelius
mesh_terms: D000818:Animals; D029742:Caenorhabditis elegans Proteins; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D004789:Enzyme Activation; D005341:Fibrinolysin / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000502:physiology; D008264:Macrophages / Q000201:enzymology*; D051379:Mice; D010196:Pancreatic Elastase / Q000235:genetics / Q000378:metabolism*; D010958:Plasminogen / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000502:physiology*; D018179:Receptors, Thrombin / Q000502:physiology; D012697:Serine Endopeptidases / Q000502:physiology*; D013917:Thrombin / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D029742:Caenorhabditis elegans Proteins; D018179:Receptors, Thrombin; D010958:Plasminogen; D003513:Cycloheximide; D017346:Protein Serine-Threonine Kinases; D012697:Serine Endopeptidases; D010196:Pancreatic Elastase; D013917:Thrombin; D005341:Fibrinolysin; D019204:GTP-Binding Proteins