title: Bupivacaine-induced apoptosis independently of WDR35 expression in mouse neuroblastoma Neuro2a cells.
abstract: BACKGROUND
  Bupivacaine-induced neurotoxicity has been shown to occur through apoptosis. Recently, bupivacaine was shown to elicit reactive oxygen species (ROS) production and induce apoptosis accompanied by activation of p38 mitogen-activated protein kinase (MAPK) in a human neuroblastoma cell line. We have reported that WDR35, a WD40-repeat protein, may mediate apoptosis through caspase-3 activation. The present study was undertaken to test whether bupivacaine induces apoptosis in mouse neuroblastoma Neuro2a cells and to determine whether ROS, p38 MAPK, and WDR35 are involved.
  
  
  RESULTS
  Our results showed that bupivacaine induced ROS generation and p38 MAPK activation in Neuro2a cells, resulting in apoptosis. Bupivacaine also increased WDR35 expression in a dose- and time-dependent manner. Hydrogen peroxide (H(2)O(2)) also increased WDR35 expression in Neuro2a cells. Antioxidant (EUK-8) and p38 MAPK inhibitor (SB202190) treatment attenuated the increase in caspase-3 activity, cell death and WDR35 expression induced by bupivacaine or H(2)O(2). Although transfection of Neuro2a cells with WDR35 siRNA attenuated the bupivacaine- or H(2)O(2)-induced increase in expression of WDR35 mRNA and protein, in contrast to our previous studies, it did not inhibit the increase in caspase-3 activity in bupivacaine- or H(2)O(2)-treated cells.
  
  
  CONCLUSIONS
  In summary, our results indicated that bupivacaine induced apoptosis in Neuro2a cells. Bupivacaine induced ROS generation and p38 MAPK activation, resulting in an increase in WDR35 expression, in these cells. However, the increase in WDR35 expression may not be essential for the bupivacaine-induced apoptosis in Neuro2a cells. These results may suggest the existence of another mechanism of bupivacaine-induced apoptosis independent from WDR35 expression in Neuro2a cells.
authors.affiliation: Department of Anesthesiology, Aichi Medical University School of Medicine, Nagakute, Aichi 480-1195, Japan.
authors.forename: Misako
authors.initials: M
authors.lastname: Harato
authors.forename: Lei
authors.initials: L
authors.lastname: Huang
authors.forename: Fumio
authors.initials: F
authors.lastname: Kondo
authors.forename: Koji
authors.initials: K
authors.lastname: Tsunekawa
authors.forename: Guo-Gang
authors.initials: GG
authors.lastname: Feng
authors.forename: Jun-Hua
authors.initials: JH
authors.lastname: Fan
authors.forename: Naohisa
authors.initials: N
authors.lastname: Ishikawa
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fujiwara
authors.forename: Shoshiro
authors.initials: S
authors.lastname: Okada
mesh_terms: D000779:Anesthetics, Local / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D002045:Bupivacaine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D053148:Caspase 3 / Q000378:metabolism; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D003598:Cytoskeletal Proteins; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005029:Ethylenediamines / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D009942:Organometallic Compounds / Q000494:pharmacology; D016877:Oxidants / Q000037:antagonists & inhibitors / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000096:biosynthesis
chemical_list: D000779:Anesthetics, Local; D000975:Antioxidants; D003598:Cytoskeletal Proteins; D004791:Enzyme Inhibitors; D005029:Ethylenediamines; D007093:Imidazoles; D047908:Intracellular Signaling Peptides and Proteins; D009942:Organometallic Compounds; D016877:Oxidants; D011506:Proteins; D011725:Pyridines; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C558597:WDR35 protein, mouse; C090577:N,N'-bis(salicylideneamino)ethane-manganese(II); D006861:Hydrogen Peroxide; D048051:p38 Mitogen-Activated Protein Kinases; C505409:Casp3 protein, mouse; D053148:Caspase 3; C090942:4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole; D002045:Bupivacaine