title: Extension of ischemic therapeutic time window by a free radical scavenger, Edaravone, reperfused with tPA in rat brain.
abstract: 3-methyl-1-phenyl-2-pyrazolin-5-one (Edaravone) is a free radical scavenger. We tested the hypothesis that combination treatment of Edaravone and recombinant tissue plasminogen activator (tPA) extends the therapeutic time window. Male Wistar rats were subjected to 1.5-, 3.0- or 4.5-hour middle cerebral artery (MCA) occlusion (MCAO) by a nylon thread. Animals were randomly divided into four groups. The Sham group rats were operated without MCAO and drug injection. In the Vehicle-treated group the same volume of saline was given every 1.5 hours from just after MCAO to just before reperfusion. In the Vehicle + tPA-treated group saline injection was given as above and tPA (5 mg/kg, i.v.) was given once just after reperfusion. Edaravone+tPA-treated group: Edaravone (3 mg/kg, i.v.) was given every 1.5 hours instead of saline and tPA injection as above. Survival rate, infarct size and evidence of apoptosis and hemorrhage were examined in the animals. Combining administration of Edaravone+tPA significantly increased survival rate after 3 hours of transient MCAO, and reduced infarct volume after 1.5 hours of transient MCAO compared with the vehicle or vehicle+tPA groups. In Edaravone+tPA-treated group, the number of terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick end labeling (TUNEL) and 4-hydroxynonenal (4-HNE) positive cells were reduced at 16 hours after 3 hours of transient MCAO, but not in advanced glycation end products (AGEs) and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Hemorrhage rate and the area decreased in the Edaravone+tPA-treated group. The combination therapy of Edaravone+tPA increased survival rate, and reduced the infarct volume and hemorrhage with reduction of lipid peroxidation. Therefore, Edaravone combination is expected to extend the therapeutic time window of tPA in the clinical situation.
authors.affiliation: Department of Neurology, Graduate School of Medicine and Dentistry, Okayama University, 2-5-1 Shikatacho, Okayama, Japan.
authors.forename: Wenri
authors.initials: W
authors.lastname: Zhang
authors.forename: Keiko
authors.initials: K
authors.lastname: Sato
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hayashi
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Omori
authors.forename: Isao
authors.initials: I
authors.lastname: Nagano
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Kato
authors.forename: Seikoh
authors.initials: S
authors.lastname: Horiuchi
authors.forename: Koji
authors.initials: K
authors.lastname: Abe
mesh_terms: D000447:Aldehydes / Q000378:metabolism; D000818:Animals; D000983:Antipyrine / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D002545:Brain Ischemia / Q000150:complications / Q000188:drug therapy* / Q000209:etiology / Q000517:prevention & control*; D002452:Cell Count / Q000379:methods; D003839:Deoxyadenosines / Q000378:metabolism; D004195:Disease Models, Animal; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D000077553:Edaravone; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D016166:Free Radical Scavengers / Q000627:therapeutic use*; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006470:Hemorrhage / Q000209:etiology / Q000473:pathology; D007150:Immunohistochemistry / Q000379:methods; D020287:In Situ Nick-End Labeling / Q000379:methods; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D016019:Survival Analysis; D013778:Tetrazolium Salts; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*
chemical_list: C436623:8-hydroxy-2'-deoxyadenosine; D000447:Aldehydes; D003839:Deoxyadenosines; D005343:Fibrinolytic Agents; D016166:Free Radical Scavengers; D017127:Glycation End Products, Advanced; D013778:Tetrazolium Salts; C009591:triphenyltetrazolium; D010959:Tissue Plasminogen Activator; C027576:4-hydroxy-2-nonenal; D000077553:Edaravone; D000983:Antipyrine