Patterns of gene expression in carp liver after exposure to a mixture of waterborne and dietary cadmium using a custom-made microarray.
Gene expression changes in carp liver tissue were studied after acute (3 and 24h) and subchronic (7 and 28 days) exposure to a mixture of waterborne (9, 105 and 480 microg/l) and dietary (9.5, 122 and 144 microg/g) cadmium, using a custom-made microarray. Suppression subtractive hybridization-PCR (SSH-PCR) was applied to isolate a set of 643 liver genes, involved in multiple biological pathways, such as energy metabolism (e.g. glucokinase), immune response (e.g. complement C3) and stress and detoxification (e.g. cytochrome P450 2F2, glutathione-S-transferase pi). These genes were subsequently spotted on glass-slides for the construction of a custom-made microarray. Resulting microarray hybridizations indicated a highly dynamic response to cadmium exposure. At low exposure concentrations (9 microg/l through water and 9.5 microg/g dry weight through food) mostly energy-related genes (e.g. glucokinase, elastase) were influenced, while a general stress response was obvious through induction of several stress-related genes, including hemopexin and cytochrome P450 2F2, at high cadmium concentrations. In addition, fish exposed to the highest cadmium concentrations showed liver damage after 7 days of exposure, as measured by elevated alanine transaminase activity in plasma and increased liver water content (wet-to-dry weight ratio). Moreover, decreased hematocrit and growth were found at the end of the experiment. Altogether this study clearly demonstrated the importance of varying exposure conditions for the characterization of the molecular impact of cadmium and showed that microarray results can provide important information, required to unravel the molecular events and responses related to cadmium exposure.
Reynders
Hans
H
Department of Biology, Research Unit Ecophysiology, Biochemistry and Toxicology Group, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. hans.reynders@ua.ac.be
van der Ven
Karlijn
K
Moens
Lotte N
LN
van Remortel
Piet
P
De Coen
Wim M
WM
Blust
Ronny
R
D000818:Animals; D002104:Cadmium / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*; D002347:Carps / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017931:DNA Primers / Q000737:chemistry; D015870:Gene Expression / Q000187:drug effects*; D008099:Liver / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism; D009835:Oligochaeta / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000662:veterinary; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D017931:DNA Primers; D014874:Water Pollutants, Chemical; D002104:Cadmium