title: Kelch-like ECH-associated Protein 1-dependent Nuclear Factor-E2-related Factor 2 Activation in Relation to Antioxidation Induced by Sevoflurane Preconditioning.
abstract: BACKGROUND
  The authors have reported that antioxidative effects play a crucial role in the volatile anesthetic-induced neuroprotection. Accumulated evidence shows that endogenous antioxidation could be up-regulated by nuclear factor-E2-related factor 2 through multiple pathways. However, whether nuclear factor-E2-related factor 2 activation is modulated by sevoflurane preconditioning and, if so, what is the signaling cascade underlying upstream of this activation are still unknown.
  
  
  METHODS
  Sevoflurane preconditioning in mice was performed with sevoflurane (2.5%) 1 h per day for five consecutive days. Focal cerebral ischemia/reperfusion injury was induced by middle cerebral artery occlusion. Expression of nuclear factor-E2-related factor 2, kelch-like ECH-associated protein 1, manganese superoxide dismutase, thioredoxin-1, and nicotinamide adenine dinucleotide phosphate quinolone oxidoreductase-1 was detected (n = 6). The antioxidant activities and oxidative product expression were also examined. To determine the role of kelch-like ECH-associated protein 1 inhibition-dependent nuclear factor-E2-related factor 2 activation in sevoflurane preconditioning-induced neuroprotection, the kelch-like ECH-associated protein 1-nuclear factor-E2-related factor 2 signal was modulated by nuclear factor-E2-related factor 2 knockout, kelch-like ECH-associated protein 1 overexpression lentivirus, and kelch-like ECH-associated protein 1 deficiency small interfering RNA (n = 8). The infarct volume, neurologic scores, and cellular apoptosis were assessed.
  
  
  RESULTS
  Sevoflurane preconditioning elicited neuroprotection and increased nuclear factor-E2-related factor 2 nuclear translocation, which in turn up-regulated endogenous antioxidation and reduced oxidative injury. Sevoflurane preconditioning reduced kelch-like ECH-associated protein 1 expression. Nuclear factor-E2-related factor 2 ablation abolished neuroprotection and reversed sevoflurane preconditioning by mediating the up-regulation of antioxidants. Kelch-like ECH-associated protein 1 overexpression reversed nuclear factor-E2-related factor 2 up-regulation and abolished the neuroprotection induced by sevoflurane preconditioning. Kelch-like ECH-associated protein 1 small interfering RNA administration improved nuclear factor-E2-related factor 2 expression and the outcome of mice subjected to ischemia/reperfusion injury.
  
  
  CONCLUSIONS
  Kelch-like ECH-associated protein 1 down-regulation-dependent nuclear factor-E2-related factor 2 activation underlies the ability of sevoflurane preconditioning to activate the endogenous antioxidant response, which elicits its neuroprotection.
authors.affiliation: From the Department of Anesthesiology and Perioperative Medicine, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China (M.C., L.T., B.D., W.H., L.S., H.D.); and Anesthesia and Operation Center, Chinese PLA General Hospital, Beijing, China (L.T.).
authors.forename: Min
authors.initials: M
authors.lastname: Cai
authors.forename: Li
authors.initials: L
authors.lastname: Tong
authors.forename: Beibei
authors.initials: B
authors.lastname: Dong
authors.forename: Wugang
authors.initials: W
authors.lastname: Hou
authors.forename: Likai
authors.initials: L
authors.lastname: Shi
authors.forename: Hailong
authors.initials: H
authors.lastname: Dong
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D004195:Disease Models, Animal; D000072019:Kelch-Like ECH-Associated Protein 1 / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D051379:Mice; D018345:Mice, Knockout; D051267:NF-E2-Related Factor 2 / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D000066829:Neuroprotection / Q000187:drug effects*; D015427:Reperfusion Injury / Q000517:prevention & control*; D000077149:Sevoflurane; D015398:Signal Transduction / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D018685:Anesthetics, Inhalation; D000975:Antioxidants; D000072019:Kelch-Like ECH-Associated Protein 1; D008738:Methyl Ethers; D051267:NF-E2-Related Factor 2; D000077149:Sevoflurane