title: Interaction of ARC and Daxx: A Novel Endogenous Target to Preserve Motor Function and Cell Loss after Focal Brain Ischemia in Mice.
abstract: The aim of this study was to explore the signaling and neuroprotective effect of transactivator of transcription (TAT) protein transduction of the apoptosis repressor with CARD (ARC) in in vitro and in vivo models of cerebral ischemia in mice. In mice, transient focal cerebral ischemia reduced endogenous ARC protein in neurons in the ischemic striatum at early reperfusion time points, and in primary neuronal cultures, RNA interference resulted in greater neuronal susceptibility to oxygen glucose deprivation (OGD). TAT.ARC protein delivery led to a dose-dependent better survival after OGD. Infarct sizes 72 h after 60 min middle cerebral artery occlusion (MCAo) were on average 30 ± 8% (mean ± SD; p = 0.005; T2-weighted MRI) smaller in TAT.ARC-treated mice (1 μg intraventricularly during MCAo) compared with controls. TAT.ARC-treated mice showed better performance in the pole test compared with TAT.β-Gal-treated controls. Importantly, post-stroke treatment (3 h after MCAo) was still effective in affording reduced lesion volume by 20 ± 7% (mean ± SD; p < 0.05) and better functional outcome compared with controls. Delayed treatment in mice subjected to 30 min MCAo led to sustained neuroprotection and functional behavior benefits for at least 28 d. Functionally, TAT.ARC treatment inhibited DAXX-ASK1-JNK signaling in the ischemic brain. ARC interacts with DAXX in a CARD-dependent manner to block DAXX trafficking and ASK1-JNK activation. Our work identifies for the first time ARC-DAXX binding to block ASK1-JNK activation as an ARC-specific endogenous mechanism that interferes with neuronal cell death and ischemic brain injury. Delayed delivery of TAT.ARC may present a promising target for stroke therapy.
  
  
  
  Up to now, the only successful pharmacological target of human ischemic stroke is thrombolysis. Neuroprotective pharmacological strategies are needed to accompany therapies aiming to achieve reperfusion. We describe that apoptosis repressor with CARD (ARC) interacts and inhibits DAXX and proximal signals of cell death. In a murine stroke model mimicking human malignant infarction in the territory of the middle cerebral artery, TAT.ARC salvages brain tissue when given during occlusion or 3 h delayed with sustained functional benefits (28 d). This is a promising novel therapeutic approach because it appears to be effective in a model producing severe injury by interfering with an array of proximal signals and effectors of the ischemic cascade, upstream of JNK, caspases, and BIM and BAX activation.
authors.affiliation: Center for Stroke Research, Max-Delbrück Center for Molecular Medicine, D-13092 Berlin, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Donath
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Junfeng
authors.initials: J
authors.lastname: An
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Sabrina Lin Lin
authors.initials: SL
authors.lastname: Lee
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, Neurology, and.
authors.forename: Karen
authors.initials: K
authors.lastname: Gertz
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Anna Lena
authors.initials: AL
authors.lastname: Datwyler
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, Neurology, and.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Harms
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Susanne
authors.identifier: 0000-0002-5053-2211
authors.initials: S
authors.lastname: Müller
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Tracy Deanne
authors.initials: TD
authors.lastname: Farr
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, German Center for Neurodegenerative Diseases, D-10117 Berlin, Germany.
authors.forename: Martina
authors.identifier: 0000-0002-1815-2745
authors.initials: M
authors.lastname: Füchtemeier
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Gisela
authors.identifier: 0000-0001-6485-1136
authors.initials: G
authors.lastname: Lättig-Tünnemann
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Janet
authors.identifier: 0000-0003-3011-4386
authors.initials: J
authors.lastname: Lips
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Marco
authors.initials: M
authors.lastname: Foddis
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Larissa
authors.initials: L
authors.lastname: Mosch
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: René
authors.initials: R
authors.lastname: Bernard
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology.
authors.forename: Ulrike
authors.identifier: 0000-0003-2595-0224
authors.initials: U
authors.lastname: Grittner
authors.affiliation: Departments of Experimental Neurology.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Balkaya
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, Psychiatry.
authors.forename: Golo
authors.initials: G
authors.lastname: Kronenberg
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, Neurology, and Cluster of Excellence NeuroCure Charité-Universitätsmedizin Berlin, D-10117 Berlin, Germany, German Center for Neurodegenerative Diseases, D-10117 Berlin, Germany, German Center for Cardiovascular Diseases, D-10117 Berlin, Germany, and Berlin Institute of Health, D-10117 Berlin, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Dirnagl
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, Neurology, and Cluster of Excellence NeuroCure Charité-Universitätsmedizin Berlin, D-10117 Berlin, Germany, German Center for Neurodegenerative Diseases, D-10117 Berlin, Germany, German Center for Cardiovascular Diseases, D-10117 Berlin, Germany, and Berlin Institute of Health, D-10117 Berlin, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Endres
authors.affiliation: Center for Stroke Research, Departments of Experimental Neurology, Neurology, and Berlin Institute of Health, D-10117 Berlin, Germany christoph.harms@charite.de.
authors.forename: Christoph
authors.identifier: 0000-0002-2063-2860
authors.initials: C
authors.lastname: Harms
mesh_terms: D000818:Animals; D017209:Apoptosis; D002545:Brain Ischemia / Q000378:metabolism* / Q000473:pathology*; D002352:Carrier Proteins / Q000378:metabolism*; D056970:Co-Repressor Proteins; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D015696:Gene Products, tat / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018832:Molecular Chaperones; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D011485:Protein Binding; D060066:Protein Interaction Maps
chemical_list: D002352:Carrier Proteins; D056970:Co-Repressor Proteins; D003598:Cytoskeletal Proteins; C491473:Daxx protein, mouse; D015696:Gene Products, tat; D047908:Intracellular Signaling Peptides and Proteins; D018832:Molecular Chaperones; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; C092069:activity regulated cytoskeletal-associated protein
keywords: TAT protein transduction; behavioral outcome; brain ischemia; endogenous neuroprotection; middle cerebral artery occlusion; penumbra