Abstract |
Gilthead sea bream larvae (Sparus aurata) aged 47 days post hatching (dph) (11.6-12.8 mg in wet weight) were exposed to several sublethal concentrations of Cd(2+) (0.1, 5 and 10 mg/L) during 6 days in order to investigate the effects of this heavy metal on the expression of selected genes involved in detoxification ( metallothionein-mt, glutathione peroxidase 1-gpx1), stress response ( heat shock protein 70-hsp70, tumour necrosis factor α-tnfα) and ossification ( osteocalcin-oc) processes. For this purpose, specimens of 47 dph were exposed first for 72 h from 0.1 to 20 mg/L of Cd(2+) in order to evaluate the median lethal concentration (LC(50)) for this metal, which was determined at 15.32 mg/L. Considering the results regarding the relative transcript levels of gpx1 and hsp70, Cd(2+) at any of the tested levels (0.1, 5 and 10 mg/L) did not induce oxidative stress in gilthead sea bream larvae, whereas relative transcript levels of mt were increased at 5 and 10 mg/L of Cd(2+) probably to detoxify this metal excess. Relative transcript levels of tnfα were not level dependent and were down-regulated in larvae exposed to 5 and 10 mg/L of Cd(2+). At those concentrations, transcript levels of oc were down-regulated suggesting a disruption in bone mineralization. Results from this study provided insights in some molecular mechanisms underlying Cd(2+)-induced toxicity in fish at early stages of development. This is the first study to show that cadmium contamination can depress oc expression in teleosts.
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Authors | Asma Sassi, Maria José Darias, Khaled Said, Imed Messaoudi, Enric Gisbert |
Journal | Fish physiology and biochemistry
(Fish Physiol Biochem)
Vol. 39
Issue 3
Pg. 649-59
(Jun 2013)
ISSN: 1573-5168 [Electronic] Netherlands |
PMID | 23053610
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
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Topics |
- Animals
- Cadmium
(toxicity)
- DNA Primers
(genetics)
- Dose-Response Relationship, Drug
- Gene Expression Regulation
(drug effects)
- Larva
(drug effects, metabolism)
- Lethal Dose 50
- Osteogenesis
(drug effects)
- Real-Time Polymerase Chain Reaction
- Sea Bream
(genetics, metabolism)
- Stress, Physiological
(drug effects)
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