Urokinase-type plasminogen activator regulates neurodegeneration and neurogenesis but not vascular changes in the mouse hippocampus after status epilepticus

• Published in: Neurobiology of disease 2010-03, Vol.37 (3), p.692-703
• Main Authors: Lahtinen, Laura, Ndode-Ekane, Xavier Ekolle, Barinka, Filip, Akamine, Yumiko, Esmaeili, Mohammed Hossein, Rantala, Jukka, Pitkänen, Asla
• Format: Article
• Language: English
• Subjects: Angiogenesis; Animals; Cell Movement - physiology; Cerebral Arteries - metabolism; Cerebral Arteries - pathology; Cerebral Arteries - physiopathology; Cytoprotection - physiology; Disease Models, Animal; Epilepsy; Epilepsy - metabolism; Epilepsy - pathology; Epilepsy - physiopathology; Epileptogenesis; Granule cell dispersion; Hippocampus; Hippocampus - metabolism; Hippocampus - pathology; Hippocampus - physiopathology; Kainic Acid - toxicity; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Microtubule-Associated Proteins - metabolism; Neovascularization, Pathologic - metabolism; Neovascularization, Pathologic - pathology; Neovascularization, Pathologic - physiopathology; Nerve Degeneration - metabolism; Nerve Degeneration - pathology; Nerve Degeneration - physiopathology; Neurodegeneration; Neurogenesis; Neurogenesis - physiology; Neurology; Neuropeptides - metabolism; Neurotoxins - toxicity; Plasminogen; Proteinase; Pyramidal Cells - metabolism; Pyramidal Cells - pathology; Status Epilepticus - metabolism; Status Epilepticus - pathology; Status Epilepticus - physiopathology; Stem Cells - metabolism; Urokinase-Type Plasminogen Activator - genetics; Urokinase-Type Plasminogen Activator - metabolism
• ISSN: 0969-9961; 1095-953X
• DOI: 10.1016/j.nbd.2009.12.008

Abstract Expression of urokinase-type plasminogen activator (uPA) is increased after brain injury, suggesting that, like in cancer tissue, uPA plays roles in brain remodeling. Here we injured brain with intrahippocampal kainic acid (KA) injection in adult Wt and uPA−/− mice. At 20 days post-injury, uPA−/− mice had more severe loss of contralateral pyramidal ( p < 0.05) and hilar neurons ( p < 0.05) than Wt mice. The number of doublecortin (DCX)-positive newly born neurons was also reduced in uPA−/− mice as compared to Wt ( p < 0.01). No difference was observed in granule cell dispersion or distribution of DCX-positive neurons in the dentate gyrus. uPA deficiency did not affect the total length of hippocampal blood vessels or vessel density. No differences were observed in the severity of status epilepticus or consequent epilepsy between the genotypes. These data indicate that uPA deficiency can unfavorably modulate both delayed neurodegeneration and neurogenesis but has little effect on post-injury neuronal migration and vascular density. Our results favor the idea that elevated uPA during the post-injury phase is neuroprotective.