title: Analysis of the protective biochemical and pathologic effects of aminoguanidine on an experimental aspiration pneumonitis model induced by bile acids.
abstract: BACKGROUND
  Gastroesophageal reflux (GER) is a common clinical pathology detected in childhood. Bile acids (BAs) are present in reflux and cause various pathologies in the esophagus, the larynx, and the lungs.
  
  
  OBJECTIVE
  We aimed to show if aminoguanidine (AG) contributes to the biochemical and histopathologic treatment of experimental aspiration pneumonitis induced by BAs.
  
  
  METHODS
  Twenty-eight female Sprague Dawley rats were used. There were 4 groups in the study: (1) group aspirated with 0.9% saline (n = 7), (2) group aspirated with 0.9% saline and treated with AG (n = 7), (3) group aspirated with a solution of 10 mg/kg taurocholic acid and 5 mg/kg taurochenodeoxycholate (n = 7), and (4) group aspirated with BA and treated with AG (n = 7). The saline and BA solutions were administered as 1 mL/kg intratracheally. The AG was administered intraperitoneally twice a day at a 150 mg/kg dose for 7 days. The different histopathologic and biochemical parameters were analyzed.
  
  
  RESULTS
  Clara cell protein 16 and malondialdehyde levels were found to be significantly higher in the BA group than in the group where saline was administered; however, they were significantly lower in the BA + AG group than in the BA group. The total superoxide dismutase activity decreased significantly in the BA group compared with the group where saline was administered. A significant increase in superoxide dismutase activity was observed in the BA + AG group when compared with the group where only BA was administered. When the group where BA was administered solely was compared with the group where saline was administered, peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar histiocytes, interstitial fibrosis, and granuloma were significantly higher in the BA group than in the saline group. When the BA + AG group was compared with the BA group, peribronchial inflammatory cell infiltration, alveolar septal infiltration, alveolar histiocytes, interstitial fibrosis, and granuloma were found to be significantly lower.
  
  
  CONCLUSIONS
  Oxidant stress increases and antioxidant capacity decreases in pneumonitis induced by BAs. AG administration as an antioxidant helps in recovery, both biochemically and histopathologically. Consequently, AG seems to be an alternative that should be considered in a conservative approach to treating aspiration pneumonitis.
authors.affiliation: Department of Otorhinolaryngology, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Rifat
authors.initials: R
authors.lastname: Karli
authors.affiliation: Department of Medical Biochemistry, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Hasan
authors.initials: H
authors.lastname: Alacam
authors.affiliation: Department of Emergency Medicine, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Latif
authors.initials: L
authors.lastname: Duran
authors.affiliation: Department of Pathology, Samsun Education and Research Hospital, Samsun, Turkey.
authors.forename: Omer
authors.initials: O
authors.lastname: Alici
authors.affiliation: Department of Otorhinolaryngology, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Celal
authors.initials: C
authors.lastname: Kati
authors.affiliation: Department of Pediatric Infection, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Arzu
authors.initials: A
authors.lastname: Karli
authors.affiliation: Department of Pediatrics, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Guzel
keywords: CC-16; aminoguanidine; aspiration pneumonitis; bile acids; gastroesophageal reflux