title: [Effects of losartan on pulmonary dendritic cells in lipopolysaccharide- induced acute lung injury mice].
abstract: OBJECTIVE
  To assess the effects of losartan on the frequency and phenotype of respiratory dendritic cells (DC) in lipopolysaccharide (LPS)-induced acute lung injury (ALI) mice.
  
  
  METHODS
  The C57BL/6 mice were randomly divided into 3 groups of control, ALI and ALI+losartan. ALI animals received 2 mg/kg of LPS; ALI+losartan animals 2 mg/kg of LPS and 15 mg/kg of losartan 30 min before an intratracheal injection of LPS; control animals phosphate buffer saline (PBS) instead of LPS. Lung wet weight/body weight (LW/BW) was recorded to assess lung injury. The pathological changes were examined under optical microscope. The frequency and phenotype of pulmonary DC were characterized by flow cytometry. Meanwhile, the levels of IL-6 in lung homogenates were assessed by enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  (1) The LPS-induced rise in LW/BW was partially prevented by a pretreatment of losartan. (2) Histologically, widespread alveolar wall thickening caused by edema, severe hemorrhage in interstitium and alveolus and marked and diffuse interstitial infiltration of inflammatory cells were observed in the ALI group. Whereas, losartan effectively attenuated the LPS-induced pulmonary hemorrhage, leukocytic infiltration in interstitium and alveolus. (3) Meanwhile, the levels of IL-6 in lung tissue were significantly enhanced in the LPS-induced ALI mice. Yet after a pretreatment of losartan, the pulmonary level of IL-6 markedly decreased. (4) LPS dosing resulted in a rapid accumulation of DC in lung tissues and an up-regulated expression of CD80 in LPS-induced ALI. In contrast, the expression of MHC II on respiratory DC was not significantly different among groups. A pretreatment of losartan led to a marked reduction in CD80 expression on pulmonary DC (P < 0.05 vs ALI).
  
  
  CONCLUSIONS
  Losartan may down-regulate pulmonary injury by inhibiting the activation of pulmonary DC.
authors.affiliation: Department of Critical Care Medicine, Suzhou Hospital, Nanjing Medical University, Suzhou 215001, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Pengshu
authors.initials: P
authors.lastname: Zhang
authors.forename: Tao
authors.initials: T
authors.lastname: Yu
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.affiliation: ICU, Nanjing Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China, Email: haiboq2000@gmail.com.
authors.forename: Haibo
authors.initials: H
authors.lastname: Qiu
mesh_terms: D055371:Acute Lung Injury; D000818:Animals; D003713:Dendritic Cells; D004797:Enzyme-Linked Immunosorbent Assay; D015850:Interleukin-6; D008070:Lipopolysaccharides; D019808:Losartan; D051379:Mice; D008810:Mice, Inbred C57BL; D011654:Pulmonary Edema
chemical_list: D015850:Interleukin-6; D008070:Lipopolysaccharides; D019808:Losartan