title: Chitosan aerosol inhalation alleviates lipopolysaccharide- induced pulmonary fibrosis in rats.
abstract: OBJECTIVE
  Pulmonary fibrosis (PF) is an insidiously progressive scarring disorder of the alveoli and is associated with high mortality. Currently, therapies available are associated with restricted efficacy and side effects. This study aimed to investigate the effect of chitosan aerosol inhalation on lipopolysaccharide (LPS)-induced pulmonary remodeling and fibrosis in rats.
  
  
  METHODS
  A rat model of PF was established by intratracheal injection of LPS (5 mg/kg). Chitosan was nebulized to rats from day 4 to 28 after LPS injection. We analyzed the effect of chitosan on LPS-induced pulmonary remodeling and fibrosis by hematoxylin-eosin staining (HE), Masson staining, and the determination of the hydroxyproline content. The expression intensities of matrix metalloproteinase-3 (MMP-3) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were analyzed by western blots.
  
  
  RESULTS
  Histological assessments showed that chitosan aerosol inhalation attenuated the fibrotic changes in LPS-induced PF in rats. Compared with the LPS group, the fibrosis parameters were significantly improved in the LPS + chitosan group (LCh group), although not as good as those of the control group. The expressions of MMP-3 and TIMP-1 in the LCh group were markedly less than that of the LPS group on the 28th day.
  
  
  CONCLUSIONS
  Our findings show that chitosan aerosol inhalation inhibits the expression of MMP-3 and TIMP-1, and ameliorates LPS-induced pulmonary remodeling and fibrosis in rats.
authors.affiliation: Department of Anesthesiology, Changzheng Hospital, Second Military Medical University, Shanghai, People's Republic of China.
authors.forename: Lu-Lu
authors.initials: LL
authors.lastname: Zhou
authors.forename: Xing-Ying
authors.initials: XY
authors.lastname: He
authors.forename: Feng-Ying
authors.initials: FY
authors.lastname: Xu
authors.forename: Bo-Xiang
authors.initials: BX
authors.lastname: Du
authors.forename: Zui
authors.initials: Z
authors.lastname: Zou
authors.forename: Xue-Yin
authors.initials: XY
authors.lastname: Shi
mesh_terms: D000280:Administration, Inhalation; D000818:Animals; D048271:Chitosan / Q000008:administration & dosage*; D003094:Collagen / Q000378:metabolism; D008070:Lipopolysaccharides; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism; D011658:Pulmonary Fibrosis / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism
chemical_list: D008070:Lipopolysaccharides; C576839:TIMP1 protein, rat; D019715:Tissue Inhibitor of Metalloproteinase-1; D003094:Collagen; D048271:Chitosan; D019278:Matrix Metalloproteinase 3
keywords: chitosan; lipopolysaccharide; matrix metallopmteinase-3; pulmonary fibrosis; tissue inhibitor of metalloproteinase-1