title: Overexpression of myelin-associated glycoprotein after axotomy of the perforant pathway.
abstract: Myelin-associated glycoprotein (MAG) contributes to the prevention of axonal regeneration in the adult central nervous system (CNS). However, changes in MAG expression following lesions and the involvement of MAG in the failure of cortical connections to regenerate are still poorly understood. Here, we show that MAG expression is differently regulated in the entorhinal cortex (EC) and the hippocampus in response to axotomy of the perforant pathway. In the EC, MAG mRNA is transiently overexpressed by mature oligodendrocytes after lesion. In the hippocampus, MAG overexpression is accompanied by an increase in the number of MAG-expressing cells. Lastly, the participation of MAG in preventing axonal regeneration was tested in vitro, where neuraminidase treatment of axotomized entorhino-hippocampal cultures potentiates axonal regeneration. These results demonstrate that MAG expression is regulated in response to cortical axotomy, and indicate that it may limit axonal regeneration after CNS injury.
authors.affiliation: Development and Regeneration of the CNS, Cellular Biology Department, Barcelona Science Park-IRB, University of Barcelona, Josep Samitier 1-5, 08028 Barcelona, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Mingorance
authors.forename: Xavier
authors.initials: X
authors.lastname: Fontana
authors.forename: Eduardo
authors.initials: E
authors.lastname: Soriano
authors.forename: José A
authors.initials: JA
authors.lastname: Del Río
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001369:Axons / Q000187:drug effects / Q000378:metabolism*; D019771:Axotomy; D002450:Cell Communication / Q000187:drug effects / Q000235:genetics; D018920:Coculture Techniques; D018728:Entorhinal Cortex / Q000166:cytology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology; D006131:Growth Inhibitors / Q000235:genetics; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D018992:Myelin-Associated Glycoprotein / Q000096:biosynthesis / Q000235:genetics*; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology*; D009439:Neuraminidase / Q000494:pharmacology; D009836:Oligodendroglia / Q000378:metabolism; D009924:Organ Culture Techniques; D019580:Perforant Pathway / Q000293:injuries / Q000378:metabolism* / Q000601:surgery; D012333:RNA, Messenger / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D006131:Growth Inhibitors; D018992:Myelin-Associated Glycoprotein; D012333:RNA, Messenger; D009439:Neuraminidase