E-GEOD-43675 - Effect of waterborne exposure to carcinogenic PAHs on adult zebrafish hepatic transcriptome

Status
Released on 1 October 2013, last updated on 2 June 2014
Organism
Danio rerio
Samples (44)
Array (1)
Protocols (6)
Description
Several environmental pollutants, especially organic compounds such as polycyclic aromatic hydrocarbons (PAHs) are potent carcinogenic chemicals. Exposure of different fish species to PAHs causes a high prevalence and variety of tumor lesions. To identify and compare the mode of action (MOA) of different model carcinogenic PAHs, a transcriptomic study was carried out in adult zebrafish (Danio rerio) after exposure to 0.3 mg/l of benzo(a)pyrene (B(a)P) or to 7,12-dimethylbenz(a)anthracene (DMBA), both of them dissolved in dimethyl sulfoxide (DMSO; final concentration of 0.01%). Samples for microarray analysis were taken after 1 and 2 weeks of exposure. The changes in the mRNA transcription levels over the corresponding controls were compared among treatments. Correspondence analysis was able to discriminate among treatments; factor 1 separated both sampling times while factor 2 separated the compounds. A total number of 3043 transcripts was shown to be differentially regulated in at least one of the treatments. B(a)P treatment produced regulation of sequences related to GO categories associated to cell cycle and cell division whereas DMBA regulated GO terms related to oxidation/reduction responses, responses to chemicals and response to bacterium. Both compounds were able to alter many xenobiotic metabolism related genes, especially upregulating the transcription of phase I metabolism-related genes such as cytochrome P450 members (cyp1a or cyp1b), and many cancer-related genes such as the Jun B proto-oncogene (junb). Overall, these results indicated that the exposure to both PAHs was able to differentially alter the transcription levels of genes involved in both the detoxification metabolism and the cell-cycle control, including different tumor-supressor genes and oncogens. These alterations have been often related to the appearance of tumor lesions. Zebrafish were waterborne exposed to 0.3ppm BaP or DMBA for 1 and 2 weeks. After 1 and 2 weeks hepatic samples were collected from each treatment group as well as from the control group. 3 biological replicates have been collected per exposure group and time point. Each biological replicate is a pool of 5 livers. Samples from the different treatments were hybridized in an n+2 (n = 9) A-optimal loop design. Additionally, these two designs were linked by two extra hybridizations to enable comparison between time points
Experiment type
transcription profiling by array 
Contacts
Unai Vicario <unai.vicario@ehu.es>, Amaia Orbea, Dries Knapen, Lucia Vergauwen, Miren P Cajaraville, Ronny Blust, Unai Vicario-Parés
MIAME
PlatformsProtocolsFactorsProcessedRaw
Files
Investigation descriptionE-GEOD-43675.idf.txt
Sample and data relationshipE-GEOD-43675.sdrf.txt
Raw data (1)E-GEOD-43675.raw.1.zip
Array designA-MEXP-1510.adf.txt
Links