title: Rho signaling pathway targeted to promote spinal cord repair.
abstract: The Rho signaling pathway regulates the cytoskeleton and motility and plays an important role in neuronal growth inhibition. Here we demonstrate that inactivation of Rho or its downstream target Rho-associated kinase (ROK) stimulated neurite growth in primary cells of cortical neurons plated on myelin or chondroitin sulfate proteoglycan substrates. Furthermore, treatment either with C3 transferase (C3) to inactivate Rho or with Y27632 to inhibit ROK was sufficient to stimulate axon regeneration and recovery of hindlimb function after spinal cord injury (SCI) in adult mice. Injured mice were treated with a single injection of Rho or Rho-associated kinase inhibitors delivered in a protein adhesive at the lesion site. Treated animals showed long-distance regeneration of anterogradely labeled corticospinal axons and increased levels of GAP-43 mRNA in the motor cortex. Behaviorally, inactivation of Rho pathway induced rapid recovery of locomotion and progressive recuperation of forelimb-hindlimb coordination. These findings provide evidence that the Rho signaling pathway is a potential target for therapeutic interventions after spinal cord injury.
authors.affiliation: Département de Pathologie et Biologie Cellulaire, Université de Montréal, Montréal, Québec, H3T 1J4, Canada.
authors.forename: Pauline
authors.initials: P
authors.lastname: Dergham
authors.forename: Benjamin
authors.initials: B
authors.lastname: Ellezam
authors.forename: Charles
authors.initials: C
authors.lastname: Essagian
authors.forename: Hovsep
authors.initials: H
authors.lastname: Avedissian
authors.forename: William D
authors.initials: WD
authors.lastname: Lubell
authors.forename: Lisa
authors.initials: L
authors.lastname: McKerracher
mesh_terms: D036002:ADP Ribose Transferases / Q000494:pharmacology; D000577:Amides / Q000494:pharmacology; D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects; D001905:Botulinum Toxins; D002469:Cell Separation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D019922:GAP-43 Protein / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D009043:Motor Activity / Q000187:drug effects; D009044:Motor Cortex / Q000187:drug effects / Q000378:metabolism; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology; D016501:Neurites / Q000187:drug effects / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D020127:Recovery of Function / Q000187:drug effects / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D016896:Treatment Outcome; D020741:rho GTP-Binding Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D054460:rho-Associated Kinases
chemical_list: D000577:Amides; D004791:Enzyme Inhibitors; D019922:GAP-43 Protein; D047908:Intracellular Signaling Peptides and Proteins; D011725:Pyridines; D012333:RNA, Messenger; C108830:Y 27632; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D001905:Botulinum Toxins; D020741:rho GTP-Binding Proteins