title: Effect of pirfenidone on pulmonary fibrosis due to paraquat poisoning in rats.
abstract: BACKGROUND
  This study investigated the effectiveness of pirfenidone compared with antioxidants, in the prevention of pulmonary fibrosis and increasing the survival in acutely paraquat poisoned rats.
  
  
  METHODS
  Five groups of ten rats were included in this study. Three groups were poisoned with intraperitoneal injection of 15 mg/kg paraquat. Among these poisoned groups, one group was treated with vitamin C (500 mg/kg, intraperitoneal), vitamin E (200 mg/kg, intraperitoneal) and N-acetylcysteine (250 mg/kg, intravenous); two others were treated with either normal saline or pirfenidone (200 mg/kg, intravenous); two groups were not poisoned and received normal saline or pirfenidone (200 mg/kg, intravenous). All injections except paraquat were repeated in four consecutive days. On the 15th day of study a semi-quantitative determination of lung fibrosis was done using Ashcroft staging criteria on the lung sections.
  
  
  RESULTS
  Pirfenidone decreased paraquat induced lung fibrosis (p < 0.001) while antioxidants did not decrease the lung fibrosis (p = 0.413). Life expectancy decreased in paraquat + normal saline (11 days, 95% CI 7.94-14.05) and paraquat + antioxidant (11 days, 95% CI 7.77-14.23) groups. The increase in the survival of rats in paraquat/pirfenidone group was insignificant (13.4 days, 95% CI 11.13-15.67).
  
  
  CONCLUSIONS
  This study showed that pirfenidone is able to decrease pulmonary fibrosis following paraquat poisoning in a rat model.
authors.affiliation: Pulmonary and Critical Care Research Center, Tehran University of Medical Sciences, Tehran, Iran. sseifirad@gmail.com
authors.forename: Soroush
authors.initials: S
authors.lastname: Seifirad
authors.forename: Amirhossein
authors.initials: A
authors.lastname: Keshavarz
authors.forename: Shervin
authors.initials: S
authors.lastname: Taslimi
authors.forename: Shima
authors.initials: S
authors.lastname: Aran
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Abbasi
authors.forename: Alireza
authors.initials: A
authors.lastname: Ghaffari
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D004195:Disease Models, Animal; D006540:Herbicides / Q000506:poisoning*; D007274:Injections, Intraperitoneal; D007275:Injections, Intravenous; D008017:Life Expectancy; D008297:Male; D010269:Paraquat / Q000506:poisoning*; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D011728:Pyridones / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D015996:Survival Rate; D014810:Vitamin E / Q000494:pharmacology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D006540:Herbicides; D011728:Pyridones; D014810:Vitamin E; C093844:pirfenidone; D010269:Paraquat; D001205:Ascorbic Acid; D000111:Acetylcysteine