Biochemical biomarkers in Oreochromis niloticus exposed to mixtures of benzo[a]pyrene and diazinon.
Biochemical biomarkers (the activities of acetylcholinesterase, 7-ethoxyresorufin-O-deetilase, carboxylesterase, catalase, glutathione peroxidase and glutathione S-transferase) were evaluated in Nile tilapia (Oreochromis niloticus) that had been exposed to benzo[a]pyrene (BaP) and the organophosphate pesticide diazinon (DZ), at 0.5mg/L. The animals were pre-exposed to BaP for three days, and DZ was then added to both non-exposed and pre-exposed groups, being exposed for 2 and 7 additional days. The level of BaP was also measured in the bile. BaP caused the induction of phase I and II enzymes, and DZ caused carboxylesterase inhibition in gills but not in liver. AChE activity was unchanged. No significant modulation was observed in antioxidant enzymes. When in combination with BaP, DZ caused a significant decrease of EROD and GST induction. Levels of BaP in the bile were also increased in fish exposed to BaP combined with DZ, indicating an interference of DZ in responses activated by BaP.
Pereira Trídico
Camila
C
Departamento de Química e Ciências Ambientais, IBILCE / UNESP, R Cristóvão Colombo 2265, CEP 15054-000, São José do Rio Preto, SP, Brazil.
Ferreira Rodrigues
Aline Cristina
AC
Nogueira
Lilian
L
da Silva
Daniele Caetano
DC
Benedito Moreira
Altair
A
de Almeida
Eduardo Alves
EA
D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D017756:Aquaculture; D001564:Benzo(a)pyrene / Q000633:toxicity*; D015415:Biomarkers / Q000378:metabolism*; D043182:Carboxylesterase / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D023681:Cichlids / Q000378:metabolism*; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D003976:Diazinon / Q000633:toxicity*; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000633:toxicity*; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D015415:Biomarkers; D004791:Enzyme Inhibitors; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene; D002374:Catalase; D005979:Glutathione Peroxidase; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase; D043182:Carboxylesterase; D000110:Acetylcholinesterase; D003976:Diazinon