title: Therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemia/reperfusion injury in rats.
abstract: BACKGROUND
  Breviscapine injection is a Chinese herbal medicine standardized product extracted from Erigeron breviscapus (Vant.) Hand.-Mazz. It has been widely used for treating cardiovascular and cerebrovascular diseases. However, the therapeutic time window and the action mechanism of breviscapine are still unclear. The present study was designed to investigate the therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemic/reperfusion injury.
  
  
  METHODS
  Sprague-Dawley rats were subjected to middle cerebral artery occlusion for 2h followed by 24h of reperfusion. Experiment part 1 was used to investigate the therapeutic time window of breviscapine. Rats were injected intravenously with 50mg/kg breviscapine at different time-points of reperfusion. After 24h of reperfusion, neurologic score, infarct volume, brain water content and serum level of neuron specific enolase (NSE) were measured in a masked fashion. Part 2 was used to explore the therapeutic mechanism of breviscapine. 4-Hydroxy-2-nonenal (4-HNE), 8-hydroxyl-2'- deoxyguanosine (8-OHdG) and the antioxidant capacity of ischemia cortex were measured by ELISA and ferric-reducing antioxidant power (FRAP) assay, respectively. Immunofluorescence and western blot analysis were used to analyze the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1).
  
  
  RESULTS
  Part 1: breviscapine injection significantly ameliorated neurologic deficit, reduced infarct volume and water content, and suppressed the levels of NSE in a time-dependent manner. Part 2: breviscapine inhibited the increased levels of 4-HNE and 8-OHdG, and enhanced the antioxidant capacity of cortex tissue. Moreover, breviscapine obviously raised the expression of Nrf2 and HO-1 proteins after 24h of reperfusion.
  
  
  CONCLUSIONS
  The therapeutic time window of breviscapine injection for cerebral ischemia/reperfusion injury seemed to be within 5h after reperfusion. By up-regulating the expression of Nrf2/HO-1 pathway might be involved in the therapeutic mechanism of breviscapine injection.
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Chao
authors.initials: C
authors.lastname: Guo
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Yanrong
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Weng
authors.affiliation: Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Shiquan
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Guan
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Guo
authors.initials: G
authors.lastname: Wei
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China. Electronic address: handsomfish@yahoo.com.cn.
authors.forename: Miaomaio
authors.initials: M
authors.lastname: Xi
authors.affiliation: Department of Pharmacy, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, PR China. Electronic address: adwen-2012@hotmail.com.
authors.forename: Aidong
authors.initials: A
authors.lastname: Wen
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000188:drug therapy* / Q000473:pathology; D049919:Erigeron / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry / Q000627:therapeutic use*; D008297:Male; D015394:Molecular Structure; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000517:prevention & control*
chemical_list: D005419:Flavonoids; C061097:breviscapine
keywords: Apigenin-7-O-glucuronide (Pubchem CID: 5319484); Breviscapine; HO-1; I/R; Nrf2; Scutellarin-7-O-glucuronide (Pubchem CID: 185617); Therapeutic time window