title: MicroRNA-124 protects against focal cerebral ischemia via mechanisms involving Usp14-dependent REST degradation.
abstract: MicroRNAs (miRNAs) are highly conserved non-coding RNAs modulating gene expression via mRNA binding. Recent work suggests an involvement of miRNAs in cardiovascular diseases including stroke. As such, the brain-abundant miR-124 and its transcriptional repressor RE1-silencing transcription factor (REST) do not only have elementary roles in the developing and the adult brain, but also alter expression upon cerebral ischemia. However, the therapeutic potential of miR-124 against stroke and the mechanisms involved remain elusive. Here, we analyzed the therapeutic potential of ectopic miR-124 against stroke and its underlying mechanisms with regard to the interaction between miR-124 and REST. Our results show that viral vector-mediated miR-124 delivery increased the resistance of cultured oxygen-glucose-deprived cortical neurons in vitro and reduced brain injury as well as functional impairment in mice submitted to middle cerebral artery occlusion. Likewise, miR-124 induced enhanced neurovascular remodeling leading to increased angioneurogenesis 8 weeks post-stroke. While REST abundance increased upon stroke, the increase was prevented by miR-124 despite a so far unknown negative feedback loop between miR-124 and REST. Rather, miR-124 decreased the expression of the deubiquitinating enzyme Usp14, which has two conserved miR-124-binding sites in the 3'UTR of its mRNA, and thereby mediated reduced REST levels. The down-regulation of REST by miR-124 was also mimicked by the Usp14 inhibitor IU-1, suggesting that miR-124 promotes neuronal survival under ischemic conditions via Usp14-dependent REST degradation. Ectopic miR-124 expression, therefore, appears as an attractive and novel tool in stroke treatment, mediating neuroprotection via a hitherto unknown mechanism that involves Usp14-dependent REST degradation.
authors.affiliation: Department of Neurology, Faculty of Medicine, University Duisburg-Essen, Hufelandstr. 55, 45147, Essen, Germany. thorsten.doeppner@uk-essen.de
authors.forename: Thorsten R
authors.initials: TR
authors.lastname: Doeppner
authors.forename: Maria
authors.initials: M
authors.lastname: Doehring
authors.forename: Eva
authors.initials: E
authors.lastname: Bretschneider
authors.forename: Anil
authors.initials: A
authors.lastname: Zechariah
authors.forename: Britta
authors.initials: B
authors.lastname: Kaltwasser
authors.forename: Barbara
authors.initials: B
authors.lastname: Müller
authors.forename: Jan C
authors.initials: JC
authors.lastname: Koch
authors.forename: Mathias
authors.initials: M
authors.lastname: Bähr
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Hermann
authors.forename: Uwe
authors.initials: U
authors.lastname: Michel
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D002154:Calpain / Q000378:metabolism; D002470:Cell Survival / Q000502:physiology; D005947:Glucose / Q000494:pharmacology; D057809:HEK293 Cells; D006801:Humans; D015227:Lipid Peroxidation / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000502:physiology*; D009474:Neurons / Q000473:pathology* / Q000502:physiology; D010100:Oxygen / Q000494:pharmacology; D018091:Receptors, AMPA / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism*; D020521:Stroke / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D043222:Ubiquitin Thiolesterase / Q000378:metabolism*; D054875:Ubiquitination / Q000502:physiology; D000099229:RE1-Silencing Transcription Factor
chemical_list: D002154:Calpain; D005947:Glucose; D035683:MicroRNAs; D010100:Oxygen; D018091:Receptors, AMPA; D012097:Repressor Proteins; D017392:Thiobarbituric Acid Reactive Substances; D043222:Ubiquitin Thiolesterase; D000099229:RE1-Silencing Transcription Factor; C540079:Mirn124 microRNA, mouse; C469268:Usp14 protein, mouse; C104722:glutamate receptor ionotropic, AMPA 2