title: Peroxiredoxin 2 battles poly(ADP-ribose) polymerase 1- and p53-dependent prodeath pathways after ischemic injury.
abstract: OBJECTIVE
  Ischemic/reperfusion neuronal injury is characterized by accumulation of reactive oxygen species and oxidative DNA damage, which can trigger cell death by various signaling pathways. Two of these modes of death include poly(ADP-ribose) polymerase 1-mediated death or p53- and Bax-mediated apoptosis. The present study tested the hypothesis that peroxiredoxin 2 (PRX2) attenuates DNA damage-mediated prodeath signaling using in vitro and in vivo models of ischemic injury. The impact of this peroxide scavenger on p53- and poly(ADP-ribose) polymerase 1-mediated ischemic death is unknown.
  
  
  METHODS
  Neuronal PRX2 overexpression in primary cortical cultures and transgenic mice was combined with the poly(ADP-ribose) polymerase 1 inhibitor AG14361. AG14361 was also applied to p53 and Bax knockout cultures and mice and combined with the JNK inhibitor SP600125. DCF fluorescence, apurinic/apyrimidinic sites, single-strand breaks, Comet tail-length, nicotinamide adenine dinucleotide depletion, and viability were assessed in response to oxygen-glucose deprivation in cultures or transient focal cerebral ischemia in mice.
  
  
  RESULTS
  PRX2 attenuated reactive oxygen species, DNA damage, nicotinamide adenine dinucleotide depletion, and cell death. PRX2 knockdown exacerbated neuronal death after oxygen and glucose deprivation. PRX2 ameliorated poly(ADP-ribose) polymerase 1, p53, Bax, and caspase activation after ischemia. AG14361 reduced ischemic cell death in wild-type and p53 or Bax knockout cultures and animals but had no additional effect in PRX2-overexpressing mice. AG14361 and p53 knockout elicited additive effects with SP600125 on viability in vitro. Our findings support the existence of multiple parallel prodeath pathways with some crosstalk.
  
  
  CONCLUSIONS
  The promising therapeutic candidate PRX2 can clamp upstream DNA damage and efficiently inhibit multiple prodeath cascades operating in both parallel and interactive fashions.
authors: Department of Neurosurgery, Cerebrovascular Diseases Research Institute, Xuan Wu Hospital, Capital Medical University, Beijing, China.
authors: Rehana K
authors: RK
authors: Leak
authors: Lili
authors: L
authors: Zhang
authors: Yumin
authors: Y
authors: Luo
authors: Peiying
authors: P
authors: Li
authors: Haiping
authors: H
authors: Zhao
authors: Xiangrong
authors: X
authors: Liu
authors: Feng
authors: F
authors: Ling
authors: Jianping
authors: J
authors: Jia
authors: Jun
authors: J
authors: Chen
authors: Xunming
authors: X
authors: Ji
mesh_terms: D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D017209:Apoptosis; D002545:Brain Ischemia / Q000378:metabolism / Q000473:pathology*; D002478:Cells, Cultured; D004249:DNA Damage; D006801:Humans; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009474:Neurons / Q000378:metabolism; D054464:Peroxiredoxins / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species; D015427:Reperfusion Injury; D015398:Signal Transduction; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D000873:Anthracenes; C494827:Bax protein, mouse; D017382:Reactive Oxygen Species; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; C432165:pyrazolanthrone; D054464:Peroxiredoxins; D011065:Poly(ADP-ribose) Polymerases; D048670:MAP Kinase Kinase 4