title: Hydrogen inhalation protects against acute lung injury induced by hemorrhagic shock and resuscitation.
abstract: BACKGROUND
  Hemorrhagic shock followed by fluid resuscitation (HS/R) triggers an inflammatory response and causes pulmonary inflammation that can lead to acute lung injury (ALI). Hydrogen, a therapeutic gas, has potent cytoprotective, antiinflammatory, and antioxidant effects. This study examined the effects of inhaled hydrogen on ALI caused by HS/R.
  
  
  METHODS
  Rats were subjected to hemorrhagic shock by withdrawing blood to lower blood pressure followed by resuscitation with shed blood and saline to restore blood pressure. After HS/R, the rats were maintained in a control gas of similar composition to room air or exposed to 1.3% hydrogen.
  
  
  RESULTS
  HS/R induced ALI, as demonstrated by significantly impaired gas exchange, congestion, edema, cellular infiltration, and hemorrhage in the lungs. Hydrogen inhalation mitigated lung injury after HS/R, as indicated by significantly improved gas exchange and reduced cellular infiltration and hemorrhage. Hydrogen inhalation did not affect hemodynamic status during HS/R. Exposure to 1.3% hydrogen significantly attenuated the upregulation of the messenger RNAs for several proinflammatory mediators induced by HS/R. Lipid peroxidation was reduced significantly in the presence of hydrogen, indicating antioxidant effects.
  
  
  CONCLUSIONS
  Hydrogen, administered through inhalation, may exert potent therapeutic effects against ALI induced by HS/R and attenuate the activation of inflammatory cascades.
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kohama
authors.affiliation: Kobe University Graduate School of Health Science, Kobe, Hyogo, Japan.
authors.forename: Hayato
authors.initials: H
authors.lastname: Yamashita
authors.affiliation: Kobe University Graduate School of Health Science, Kobe, Hyogo, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Aoyama-Ishikawa
authors.affiliation: Faculty of Health and Welfare Science, Okayama Prefectural University, Okayama, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Department of Surgery, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Billiar
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nishimura
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Hyogo College of Medicine, Nishinomiya, Japan.
authors.forename: Joji
authors.initials: J
authors.lastname: Kotani
authors.affiliation: Department of Emergency, Disaster and Critical Care Medicine, Hyogo College of Medicine, Nishinomiya, Japan. Electronic address: qq-nakao@hyo-med.ac.jp.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Nakao
mesh_terms: D055371:Acute Lung Injury / Q000209:etiology / Q000517:prevention & control*; D000280:Administration, Inhalation; D000818:Animals; D005440:Fluid Therapy; D006859:Hydrogen / Q000627:therapeutic use*; D008297:Male; D020011:Protective Agents / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012151:Resuscitation / Q000379:methods*; D012771:Shock, Hemorrhagic / Q000150:complications / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D020011:Protective Agents; D006859:Hydrogen