title: Pranlukast attenuates hydrogen peroxide-induced necrosis in endothelial cells by inhibiting oxygen reactive species-mediated collapse of mitochondrial membrane potential.
abstract: OBJECTIVE
  Recently, we reported that pranlukast, an antagonist of cysteinyl leukotriene receptor 1, attenuates ischemic injury in endothelial cells by decreasing reactive oxygen species (ROS) production and inhibiting nuclear factor-κB activation in a leukotriene-independent manner. In this study, we investigated the effect of pranlukast on oxidative stress injury induced by hydrogen peroxide (H2O2) in EA.hy926 cells, a human endothelial cell line, and the possible mechanisms.
  
  
  RESULTS
  We found that H2O2 reduced cell viability and increased lactate dehydrogenase release in a concentration- and time-dependent manner. Necrosis was the main death mode, and the necrotic rate increased 32% after exposure to 220 μM H2O2 for 4 hours. Pretreatment with pranlukast significantly ameliorated the reduced viability and the increased lactate dehydrogenase release and necrosis after exposure to H2O2. We next examined the mechanisms underlying the antinecrotic effects of pranlukast. The results showed that pranlukast attenuated excessive ROS production and ameliorated the reduced superoxide dismuase and glutathione peroxidase activity in EA.hy926 cells exposed to H2O2. Pranlukast also inhibited the collapse of mitochondrial membrane potential (MMP) induced by H2O2. Inhibition of ROS production by N-acetyl-l-cysteine, a powerful antioxidant, reduced MMP collapse and necrosis. Inhibition of MMP collapse by cyclosporine A, a mitochondrial permeability transition inhibitor, attenuated necrosis but failed to reduce ROS production. In addition, we found no expression of 5-lipoxygenase in EA.hy926 cells and zileuton, a 5-lipoxygenase inhibitor, did not affect the cellular injury induced by H2O2.
  
  
  CONCLUSIONS
  Pranlukast protects endothelial cells from H2O2-induced necrosis by inhibiting ROS-mediated collapse of mitochondrial membrane potential, and this is leukotriene-independent.
authors.affiliation: Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhao
authors.forename: San-Hua
authors.initials: SH
authors.lastname: Fang
authors.forename: Ka-Na
authors.initials: KN
authors.lastname: Lin
authors.forename: Xue-Qin
authors.initials: XQ
authors.lastname: Huang
authors.forename: Yun-Bi
authors.initials: YB
authors.lastname: Lu
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Zhang
authors.forename: Er-Qing
authors.initials: EQ
authors.lastname: Wei
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002867:Chromones / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage / Q000633:toxicity; D007770:L-Lactate Dehydrogenase / Q000187:drug effects / Q000378:metabolism; D020024:Leukotriene Antagonists / Q000494:pharmacology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects*; D009336:Necrosis / Q000188:drug therapy / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013997:Time Factors
chemical_list: D002867:Chromones; D020024:Leukotriene Antagonists; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase; C047681:pranlukast