Early defense responses in the freshwater bivalve Corbicula fluminea exposed to copper and cadmium: Transcriptional and histochemical studies.
The aim of the present study was to measure the early effects of copper (10 and 50 μg L(-1)), cadmium (2, 10, and 50 μg L(-1)) and mixtures of these metals in the freshwater bivalve Corbicula fluminea exposed for 12 h in laboratory. Transcription levels of superoxide dismutase (SOD), catalase (CAT), selenium-dependent glutathione peroxidase (Se-GPx), pi-class glutathione S-transferase (pi-GST), metallothionein (MT) in digestive gland and gills, and response of lysosomal system and neutral lipids in digestive gland were determined after the exposure period. Results showed that lysosomal system, neutral lipids content, and mRNA levels were modified, suggesting their early response against oxidative stress and their important role in cell integrity. The integrated biomarker response was calculated and showed that the effects of the combinations of Cu and Cd on the biomarker responses are additive. MT and pi-GST mRNA expression correspond to the largest ranges of response. As efficient biomarkers should have an early warning capacity, SOD, CAT, Se-GPx, pi-GST, MT transcripts levels, lysosomal system, and neutral lipids could be used as biomarkers of metal contamination in the aquatic environment.
Bigot
Aurélie
A
Laboratoire des Interactions Ecotoxicologie, Biodiversité, Ecosystèmes, Université Paul Verlaine-Metz, CNRS UMR 7146, Rue Delestraint, 57070 Metz, France.
Minguez
Laëtitia
L
Giambérini
Laure
L
Rodius
François
F
D000818:Animals; D002104:Cadmium / Q000378:metabolism / Q000633:toxicity*; D002374:Catalase / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000378:metabolism / Q000633:toxicity*; D049874:Corbicula / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D005618:Fresh Water / Q000737:chemistry; D005880:Gills / Q000187:drug effects / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D051549:Glutathione S-Transferase pi / Q000235:genetics / Q000378:metabolism; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D018384:Oxidative Stress; D012333:RNA, Messenger / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity*
D012333:RNA, Messenger; D014874:Water Pollutants, Chemical; D002104:Cadmium; D003300:Copper; D008668:Metallothionein; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase