Time-dependent oxidative stress responses after acute exposure to toxic cyanobacterial cells containing microcystins in tilapia fish (Oreochromis niloticus) under laboratory conditions.
Microcystins (MCs) have been reported to induce oxidative stress in aquatic organisms including fish. The effect of acute exposure to toxic cyanobacterial material containing MCs on antioxidant enzymes and lipid peroxidation has been studied in liver, kidney and gills of tilapia fish (Oreochromis niloticus). Fish were orally exposed to a single dose of cyanobacterial cells containing 120 microg/fish MC-LR and sacrificed at 24 and 72 h. The activities of glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) enzymes in the studied organs decreased in general 24 and 72 h after the dose application, although elevation of CAT and GR was found in liver at 72 h post exposure in comparison to 24h values. In contrast, the lipid peroxidation level increased significantly in all the studied organs with the liver (3.6-fold) proving to be the most affected. Protein oxidation was also increased 1.5-fold in the liver. However, recovery in these parameters was observed in liver 72 h after exposure. The results show that an acute dose of MCs does not induce an adaptative response of the antioxidant enzymes, as a sub-chronic exposure to MCs in tilapia fish does, but a general decrease in them with an initial recovery of the oxidative damage after 72 h, expressed as enhancement of CAT and GR activities and a reduction of LPO and protein oxidation in comparison to 24h values.
Area of Toxicology, Faculty of Pharmacy, University of Seville, Profesor García González no. 2, 41012 Seville, Spain.
Ana I
AI
Prieto
Area of Toxicology, Faculty of Pharmacy, University of Seville, Profesor García González no. 2, 41012 Seville, Spain.
Silvia
S
Pichardo
Area of Toxicology, Faculty of Pharmacy, University of Seville, Profesor García González no. 2, 41012 Seville, Spain. Electronic address: angelesjos@us.es.
Ángeles
Á
Jos
Area of Toxicology, Faculty of Pharmacy, University of Seville, Profesor García González no. 2, 41012 Seville, Spain.
Isabel
I
Moreno
Area of Toxicology, Faculty of Pharmacy, University of Seville, Profesor García González no. 2, 41012 Seville, Spain.
Ana M
AM
Cameán
D000818:Animals; D002374:Catalase / Q000378:metabolism; D023681:Cichlids / Q000378:metabolism*; D000458:Cyanobacteria / Q000254:growth & development / Q000378:metabolism*; D005393:Fish Diseases / Q000378:metabolism / Q000382:microbiology*; D005880:Gills / Q000201:enzymology / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D007668:Kidney / Q000201:enzymology / Q000378:metabolism; D008099:Liver / Q000201:enzymology / Q000378:metabolism; D008297:Male; D008387:Marine Toxins; D052998:Microcystins / Q000378:metabolism / Q000633:toxicity*; D018384:Oxidative Stress / Q000502:physiology*; D013482:Superoxide Dismutase / Q000378:metabolism; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D008387:Marine Toxins; D052998:Microcystins; D017392:Thiobarbituric Acid Reactive Substances; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; C057862:cyanoginosin LR