title: Mitogen-activated protein kinase inhibition in traumatic brain injury: in vitro and in vivo effects.
abstract: The authors provide the first in vitro and in vivo evidence that perturbations in mitogen-activated protein kinase (MAPK) signal-transduction pathways are involved in the pathophysiology of traumatic brain injury. In primary rat cortical cultures, mechanical trauma induced a rapid and selective phosphorylation of the extracellular signal-regulated kinase (ERK) and p38 kinase, whereas there was no detectable change in the c-jun N-terminal kinase (JNK) pathway. Treatment with PD98059, which inhibits MAPK/ERK 1/2, the upstream activator of ERK, significantly increased cell survival in vitro. The p38 kinase and JNK inhibitor SB203580 had no protective effect. Similar results were obtained in vivo using a controlled cortical impact model of traumatic injury in mouse brain. Rapid and selective upregulation occurred in ERK and p38 pathways with no detectable changes in JNK. Confocal immunohistochemistry showed that phospho-ERK colocalized with the neuronal nuclei marker but not the astrocytic marker glial fibrillary acidic protein. Inhibition of the ERK pathway with PD98059 resulted in a significant reduction of cortical lesion volumes 7 days after trauma. The p38 kinase and JNK inhibitor SB203580 had no detectable beneficial effect. These data indicate that critical perturbations in MAPK pathways mediate cerebral damage after acute injury, and further suggest that ERK is a novel therapeutic target in traumatic brain injury.
authors.affiliation: Neuroprotection Research Laboratory, Department of Radiology, Massachusetts General Hospital, Charlestown, Massachusetts, USA.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Mori
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Wang
authors.forename: Jae-Chang
authors.initials: JC
authors.lastname: Jung
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Sumii
authors.forename: Aneesh B
authors.initials: AB
authors.lastname: Singhal
authors.forename: M Elizabeth
authors.initials: ME
authors.lastname: Fini
authors.forename: C Edward
authors.initials: CE
authors.lastname: Dixon
authors.forename: Alessandro
authors.initials: A
authors.lastname: Alessandrini
authors.forename: Eng H
authors.initials: EH
authors.lastname: Lo
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism / Q000473:pathology; D001930:Brain Injuries / Q000201:enzymology / Q000378:metabolism*; D002470:Cell Survival; D002478:Cells, Cultured; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D066298:In Vitro Techniques; D020935:MAP Kinase Signaling System / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D011725:Pyridines / Q000494:pharmacology; D051381:Rats
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D007093:Imidazoles; D011725:Pyridines; D020928:Mitogen-Activated Protein Kinases; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one