title: Tissue inhibitor of metalloproteinases-3 facilitates Fas-mediated neuronal cell death following mild ischemia.
abstract: Tissue inhibitor of metalloproteinase-3 (TIMP-3) is a natural inhibitor of metalloproteinases involved in matrix degradation and ectodomain shedding of many cell-surface proteins, including death receptors and/or their ligands. In the present study, we examined the role of TIMP-3 in Fas-mediated neuronal cell death following cerebral ischemia, using both gene deletion and pharmacological approaches. In culture, exposure of primary cortical neurons to 2 h of oxygen-glucose deprivation (OGD) resulted in delayed neuronal cell death that was dependent on activation of the death receptor, Fas. Cortical cultures derived from timp-3(-/-) mice displayed partial resistance against OGD-induced neuronal cell death and also displayed increased shedding of Fas ligand (FasL) into the culture media, compared to wild-type control cultures. Both the increased neuroprotection and increased FasL shedding in timp-3(-/-) cultures were reversed by addition of exogenous metalloproteinase inhibitors, recombinant TIMP-3 or GM6001. In vivo, timp-3(-/-) mice showed marked resistance to a brief (30 min) middle cerebral artery occlusion (MCAO), but were not protected against more severe lesions induced by 90 min of MCAO. These studies demonstrate that TIMP-3 facilitates Fas-mediated neuronal cell death following OGD and plays a pro-apoptotic role in mild cerebral ischemia.
authors.affiliation: Department of Biology and Cell Biology Program, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Wetzel
authors.forename: L
authors.initials: L
authors.lastname: Li
authors.forename: K M
authors.initials: KM
authors.lastname: Harms
authors.forename: T
authors.initials: T
authors.lastname: Roitbak
authors.forename: P B
authors.initials: PB
authors.lastname: Ventura
authors.forename: G A
authors.initials: GA
authors.lastname: Rosenberg
authors.forename: R
authors.initials: R
authors.lastname: Khokha
authors.forename: L A
authors.initials: LA
authors.lastname: Cunningham
mesh_terms: D000818:Animals; D017209:Apoptosis; D002545:Brain Ischemia / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D053148:Caspase 3 / Q000378:metabolism; D015687:Cell Hypoxia; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D004151:Dipeptides / Q000494:pharmacology; D053222:Fas Ligand Protein / Q000378:metabolism; D008297:Male; D045726:Metalloproteases / Q000037:antagonists & inhibitors / Q000378:metabolism; D051379:Mice; D008817:Mice, Mutant Strains; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology* / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000378:metabolism* / Q000494:pharmacology; D019014:fas Receptor / Q000378:metabolism*
chemical_list: D004151:Dipeptides; D053222:Fas Ligand Protein; D008869:Microtubule-Associated Proteins; C079240:Mtap2 protein, mouse; C078131:N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide; D011994:Recombinant Proteins; D019717:Tissue Inhibitor of Metalloproteinase-3; D019014:fas Receptor; D045726:Metalloproteases; D053148:Caspase 3