title: Therapeutic effects of inhaling aerosolized surfactant alone or with dexamethasone generated by a novel noninvasive apparatus on acute lung injury in rats.
abstract: BACKGROUND
  Pulmonary surfactant (PS) administration has been attempted for the treatment of adults with acute lung injury (ALI)/adult respiratory distress syndrome. Aerosolized surfactants inhaled by spontaneous breathing may be an effective method of surfactant-based therapies. Using a noninvasive apparatus, we evaluated the therapeutic effects of aerosolized PS alone or together with dexamethasone (Dex) on a rat model of ALI.
  
  
  METHODS
  Severe ALI was induced by intravenous injection of 20% oleic acid (0.2 mL/kg) into adult Sprague-Dawley rats. Animals were divided into eight groups: sham (n = 10); model (injury only, n = 10); normal saline (NS) aerosol driven by compressed air (air-NS, n = 13); PS aerosol driven by compressed air (air-PS, n = 13); NS aerosol driven by O2 (O2-NS, n = 13); PS aerosol driven by O2 (O2-PS, n = 13); Dex aerosol driven by O2 (O2-Dex, n = 13); and PS and Dex aerosol driven by O2 (O2-PS-Dex, n = 13). Blood gases, breathing rate, lung index, total protein, and proinflammatory cytokines (tumor necrosis factor-α, interleukin 1β, interleukin 6) in the bronchoalveolar lavage fluid (BALF), and lung histology were examined.
  
  
  RESULTS
  Animals treated with air-PS for 20 minutes had significantly improved lung function, reduced pulmonary edema, decreased concentration of total protein and proinflammatory cytokines in BALF, ameliorated lung injury, and improved animal survival. In the O2-PS group, the breathing rates and lung injury scores were significantly lower than that of the air-PS group. In the O2-PS-Dex group, lung edema, total protein, and inflammatory cytokines in BALF were significantly reduced in comparison with the O2-PS group.
  
  
  CONCLUSIONS
  Inhalation of aerosolized PS generated by the noninvasive apparatus could significantly reduce lung injury, while using oxygen line available in the clinical wards to generate PS aerosol is more convenient and adds further benefits. This method can also be used to deliver Dex and other therapeutic agents to ameliorate lung injury.
authors.affiliation: Department of Pathophysiology, College of Basic Medical Sciences, Second Military Medical University, Shanghai, China.
authors.forename: Ya-Min
authors.initials: YM
authors.lastname: Yan
authors.forename: Yi-Dong
authors.initials: YD
authors.lastname: Li
authors.forename: Xing-Lei
authors.initials: XL
authors.lastname: Song
authors.forename: Mingyao
authors.initials: M
authors.lastname: Liu
authors.forename: Fei
authors.initials: F
authors.lastname: Diao
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Wang
authors.forename: Jian
authors.initials: J
authors.lastname: Lu
mesh_terms: D055371:Acute Lung Injury / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D000280:Administration, Inhalation; D000336:Aerosols; D000818:Animals; D003907:Dexamethasone / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D005938:Glucocorticoids / Q000008:administration & dosage*; D009330:Nebulizers and Vaporizers; D010102:Oxygen Inhalation Therapy / Q000295:instrumentation*; D011663:Pulmonary Surfactants / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000336:Aerosols; D005938:Glucocorticoids; D011663:Pulmonary Surfactants; D003907:Dexamethasone