Biotransformation in the fish Prochilodus lineatus: An organ-specific approach to cyp1a gene expression and biochemical activity

Environ Toxicol Pharmacol. 2020 Nov:80:103467. doi: 10.1016/j.etap.2020.103467. Epub 2020 Aug 11.

Abstract

The biotransformation ability of the organism is the result of organ-specific responses. This paper presents a molecular and biochemical approach to elucidate the biotransformation mechanisms in different organs of Prochilodus lineatus induced at 6, 24, and 96 h after a benzo[a]pyrene (B[a]P) injection. The induction in cyp1a transcription showed an organ-specific intensity at every tested time time. The EROD (ethoxyresorufin-O-deethylase) activity increased rapidly (6 h) in the liver and the kidney; the gills and the brain showed an increase at 24 h; and the gills demonstrated the highest activity among all the organs tested. There was no increase in glutathione S-transferase (GST) activity or lipoperoxidation. The decreased hepatic glutathione content (GSH) may be due to its role as an antioxidant. B[a]P was detected in the bile, confirming the xenobiotic efflux from the metabolizing organs. The gills, liver, brain, and kidney of P. lineatus presented an integrated mechanism to deal with the xenobiotic biotransformation.

Keywords: Benzo[a]pyrene; Bile metabolites; EROD; GST; Oxidative stress.

MeSH terms

  • Animals
  • Benzo(a)pyrene / pharmacology*
  • Bile / chemistry
  • Biotransformation
  • Brain / metabolism
  • Characiformes / genetics*
  • Characiformes / metabolism*
  • Cytochrome P-450 CYP1A1 / genetics*
  • Fish Proteins / genetics
  • Gene Expression / drug effects
  • Gills / metabolism
  • Glutathione / metabolism
  • Glutathione Transferase / metabolism
  • Kidney / metabolism
  • Liver / metabolism

Substances

  • Fish Proteins
  • Benzo(a)pyrene
  • Cytochrome P-450 CYP1A1
  • Glutathione Transferase
  • Glutathione