title: Therapeutic effects of erythropoietin in murine models of endotoxin shock.
abstract: OBJECTIVE
  Erythropoietin has recently emerged as a cytoprotective cytokine, which possesses the ability to protect many tissues, including the brain, heart, and kidneys, against ischemia or traumatic injury. We investigated the therapeutic effects of erythropoietin in a murine model of endotoxin shock.
  
  
  METHODS
  Prospective, randomized study.
  
  
  METHODS
  University-based research laboratory.
  
  
  METHODS
  Male BALB/c mice.
  
  
  METHODS
  Mice intraperitoneally received either lipopolysaccharide (LPS) from Escherichia coli or vehicle. Erythropoietin was administered at a dose of 1000 IU/kg subcutaneously at different time points after LPS administration. We also investigated the effect of erythropoietin on the development of septic shock caused by cecal perforation.
  
  
  RESULTS
  Treatment of mice with erythropoietin, within 2 hours after LPS administration, improved the mortality rate. Treatment of cecal perforated mice with erythropoietin extended survival by 12 hours, but all animals died by 72 hours in both groups. Erythropoietin attenuated apoptosis in the lungs, liver, small intestine, thymus, and spleen, as assessed by terminal deoxynucleotidyl transferase-mediated nucleotide nick-end labeling staining, active caspase-3 immunostaining and immunoblotting, and measurements of caspase-3/7 activity. Erythropoietin also reduced inducible nitric oxide synthase expression, nitric oxide production, peroxynitrite formation, and tissue hypoxia. In contrast, erythropoietin did not affect the degree of LPS-induced inflammation, as assessed by measurements of blood levels of interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, growth-related oncogene/keratinocyte-derived cytokine, and high mobility group box 1, the phosphorylation levels of nuclear factor kappaB, and the number of neutrophils infiltrating the lungs and the liver.
  
  
  CONCLUSIONS
  The results of the study demonstrate that administration of a large dose of erythropoietin after induction of experimental endotoxemia improved survival and that the beneficial effects of erythropoietin were associated with inhibition of apoptosis, nitric oxide production, and tissue hypoxia, without alterations in inflammatory responses.
authors.affiliation: First Department of Medicine, Tokyo Women's Medical University, Tokyo, Japan. kaoshiba@chi.twmu.ac.jp
authors.forename: Kazutetsu
authors.initials: K
authors.lastname: Aoshiba
authors.forename: Shigemitsu
authors.initials: S
authors.lastname: Onizawa
authors.forename: Takao
authors.initials: T
authors.lastname: Tsuji
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nagai
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004921:Erythropoietin / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012772:Shock, Septic / Q000188:drug therapy*
chemical_list: D004921:Erythropoietin