DNA damage and repair, oxidative stress and metabolism biomarker responses in lungs of rats exposed to ambient atmospheric 1-nitropyrene

Environ Toxicol Pharmacol. 2017 Sep:54:14-20. doi: 10.1016/j.etap.2017.06.009. Epub 2017 Jun 20.

Abstract

1-Nitropyrene (1-NP) is a mutagenic and carcinogenic pollutant very widespread in the environment. However, the relative investigations on genotoxicity, oxidative stress and metabolic enzymes in lungs of mammalian caused by 1-NP have not been fully established. In this study, the 1-NP solutions at 3 dosages (1.0×10-5, 4.0×10-5 and 1.6×10-4mg/kg body weight) were respectively given to rats by the intratracheal instillation. The responses of 1-NP on DNA damage and repair, oxidative stress and metabolism biomarkers in rat lungs after exposure to 1-NP were measured. The results showed 1-NP at three dosages induced obvious DNA strand breaks, 8-OH-dG formation and DNA-protein cross-link in rat lungs compared with the control. Higher dosage 1-NP (4.0×10-5 and 1.6×10-4mg/kg body weight) greatly activated DNA repair gene OGG1 and inhibited MTH1 and XRCC1 expressions, and they significantly elevated the levels of GADD153, heme oxygenase-1 and malondialdehyde and decreased SOD activity, accompanied by the increases of CYP450, CYP1A1, CYP1A2 and GST levels. These results suggested the genotoxicity of 1-NP might rely on 1-NP-caused DNA damage and its combined effects on the suppression of DNA repair and the enhancement of oxidative stress and metabolic enzyme activity.

Keywords: 1-Nitropyrene; DNA damage and repair; Metabolic enzymes; Oxidative stress; Rat lungs.

MeSH terms

  • Air Pollutants / toxicity*
  • Animals
  • Biomarkers / metabolism
  • Cytochrome P-450 Enzyme System / metabolism
  • DNA Damage
  • DNA Glycosylases / genetics
  • DNA Repair / drug effects
  • Gene Expression / drug effects
  • Glutathione Transferase / metabolism
  • Lung / drug effects*
  • Lung / metabolism
  • Male
  • Malondialdehyde / metabolism
  • Oxidative Stress / drug effects
  • Pyrenes / toxicity*
  • Pyrophosphatases / genetics
  • Pyrophosphatases / metabolism
  • Rats, Wistar
  • Superoxide Dismutase / metabolism
  • Transcription Factor CHOP / genetics
  • Transcription Factor CHOP / metabolism
  • X-ray Repair Cross Complementing Protein 1 / genetics
  • X-ray Repair Cross Complementing Protein 1 / metabolism

Substances

  • Air Pollutants
  • Biomarkers
  • Ddit3 protein, rat
  • Nudt1 protein, rat
  • Pyrenes
  • X-ray Repair Cross Complementing Protein 1
  • Xrcc1 protein, rat
  • Transcription Factor CHOP
  • Malondialdehyde
  • Cytochrome P-450 Enzyme System
  • Superoxide Dismutase
  • Glutathione Transferase
  • DNA Glycosylases
  • OGG1 protein, rat
  • Pyrophosphatases
  • 1-nitropyrene