Hepatic transcriptional signatures of exposure to oestradiol (E2) and the herbicide linuron in mature male brown trout
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ABSTRACT:
ORGANISM(S): Salmo trutta
PROVIDER: GSE57490 | GEO | 2015/05/08
SECONDARY ACCESSION(S): PRJNA246542
REPOSITORIES: GEO
Similar Datasets
Project description:These studies aimed to investigate the hepatic transcriptional response of brown trout to the natural estrogen, E2, and the herbicide linuron. We exposed mature male brown trout to three concentrations of each chemical for 4 days and sequenced the hepatic transcriptome of 3 individuals per treatment group in order to determine the global mechanisms of toxicity of these environmental contaminants. We assembled the brown trout transcriptome using a de novo approach. Subsequent differential expression analysis identified a total of 2113 differentially-regulated transcripts in the group exposed to the highest E2 treatment concentration, and 822 differentially-regulated transcripts across all linuron treatments. For E2, differentially-expressed transcripts included those encoding known oestrogen-responsive genes, while regulated processes included those associated with vitellogenesis including lipid metabolism, cellular proliferation and ribosome biogenesis. For linuron, there was a striking down-regulation of transcripts encoding the majority of the enzymes involved in the cholesterol biosynthesis pathway, and also a considerable induction of transcripts involved in cellular stress response including Cyp1a. Fish were exposed to 3 concentrations of E2 (measured concentrations were 1.9, 18.1 and 34.4 ng/L), 3 concentrations of linuron (measured concentrations were 1.7, 15.3 and 225.9 µg/L) and water controls for 4 days. Liver mRNA from 3 replicate individuals per treatment was sequenced in an Illumina HiSeq 2500 platform. Two control groups (n=6 fish in total) were included. Using a de novo approach, we assembled the hepatic transcriptome for brown trout. Sequence reads were re-mapped to the assembled transcriptome using Bowtie2 and transcript expression profiling was conducted using EdgeR. ERCC spike controls were added to all individual samples, allowing for the assessment of the reproducibility and dynamic range for transcript expression quantification in our experiments.
2015-05-08 | E-GEOD-57490 | biostudies-arrayexpress
Project description:Indole-3-carbinol (I3C), from cruciferous vegetables, has been found to suppress or enhance tumors in several animal models. We previously reported that dietary I3C promotes hepatocarcinogenesis in rainbow trout (Oncorhynchus mykiss) at concentrations that differentially activated estrogen receptor (ER) or aryl hydrocarbon receptor (AhR)-mediated responses based on individual protein biomarkers. In this study, we evaluated the relative importance of these pathways as potential mechanisms for I3C on a global scale. Hepatic gene expression profiles were examined in trout after dietary exposure to 500 and 1500 ppm I3C and 3,3,-diindolylmethane (DIM), a major in vivo component of I3C, and were compared to the transcriptional signatures of two model hepatic tumor promoters; 17beta-estradiol (E2), an ER agonist, and beta-naphthoflavone, an AhR agonist. We demonstrate that I3C and DIM acted similar to E2 at the transcriptional level based on correlation analysis of expression profiles and clustering of gene responses. Of the genes regulated by E2 (fold change >2.0 or <0.50), most genes were regulated similarly by DIM (87-92%) and I3C (71%) suggesting a common mechanism of action. Of interest were upregulated genes associated with signaling pathways for cell growth and proliferation, vitellogenesis, and protein folding, stability and transport. Other genes down-regulated by E2, including those involved in acute-phase immune response, were also down-regulated by DIM and I3C. Gene regulation was confirmed by qRT-PCR and western blot. These data indicate I3C promotes hepatocarcinogenesis through estrogenic mechanisms in trout liver and suggest DIM may be an even more potent hepatic tumor promoter in this model. Keywords: dose response
2005-09-28 | GSE3324 | GEO
Project description:This study aimed to investigate the hepatic transcriptional response of brown trout to glyphosate, and its formulated product, Roundup. We exposed juvenile female brown trout to three concentrations of glyphosate (0.01, 0.5 and 10 mg/L) and Roundup (0.01, 0.5 and 10 mg/L glyphosate acid equivalent) for 14 days and sequenced the hepatic transcriptome of 6 individual females per treatment group in order to determine the global mechanisms of toxicity of this widely used herbicide. We assembled the brown trout transcriptome using an optimised de novo approach, and subsequent differential expression analysis identified a total of 1020 differentially-regulated transcripts across all treatments. Differentially-expressed transcripts included those encoding components of the antioxidant system, a number of stress-response proteins and pro-apoptotic signalling molecules. Functional analysis also revealed over-representation of pathways involved in regulation of cell-proliferation and turnover, and up-regulation of energy metabolism and other metabolic processes. Together, these transcriptional changes are consistent with generation of oxidative stress and the widespread induction of compensatory cellular stress response pathways. The mechanisms of toxicity identified were similar across both glyphosate and Roundup treatments, including for environmentally relevant concentrations. The significant alterations in transcript expression observed at the lowest concentrations tested raises concerns for the toxicity of this herbicide to fish populations inhabiting contaminated rivers.
2015-04-16 | GSE56855 | GEO
Project description:The study aimed to characterize gene expression in rainbow trout ovary during ovarian development from immature to mature stages. Whole ovary were collected at the following stages: immature pre-vitelogenesis (IMM), mid-vitellogenesis (MV), late vitellogenesis (LV), post-vitellogenesis (PV) and mature while meiotic maturation is in progress (MAT). Gene expression in rainbow trout ovary was measured at 5 different stages (immature, mid-vitellogenesis, late vitellogenesis, post-vitellogenesis and mature). Three to four biological replicates were used for each stages.
2013-04-11 | E-GEOD-39587 | biostudies-arrayexpress
Project description:The study aimed to characterize miRNA expression in rainbow trout ovary during ovarian development from immature to mature stages. Whole ovary were collected at the following stages: immature pre-vitelogenesis (IMM), mid-vitellogenesis (MV), late vitellogenesis (LV), post-vitellogenesis (PV) and mature while meiotic maturation is in progress (MAT). miRNA expression in rainbow trout ovary was measured at 5 different stages (immature, mid-vitellogenesis, late vitellogenesis, post-vitellogenesis and mature). Two to three biological replicates were used for each stages.
2013-04-11 | E-GEOD-39588 | biostudies-arrayexpress
Project description:Background: Previously, we reported that perfluorooctanoic acid (PFOA) promotes liver cancer in manner similar to that of 17β-estradiol (E2) in rainbow trout. Also, other perfluoroalkyl acids (PFAAs) are weakly estrogenic in trout and bind the trout liver estrogen receptor (ER). Objectives: The primary objective of this study was to determine whether multiple PFAAs enhance hepatic tumorigenesis in trout, an animal model that represents human insensitivity to peroxisome proliferators. Methods: A two-stage chemical carcinogenesis model was employed in trout to evaluate PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctane sulfonate (PFOS) and 8:2 fluorotelomer alcohol (8:2FtOH) as complete carcinogens or promoters of aflatoxin B1 (AFB1)- and/or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced liver cancer. A custom trout DNA microarray was used to assess hepatic transcriptional response to these dietary treatments in comparison to E2 and the classic peroxisome proliferator clofibrate (CLOF). Results: Incidence, multiplicity and size of liver tumors in trout fed diets containing E2, PFOA, PFNA and PFDA were significantly higher compared to AFB1-initiated animals fed control diet, whereas PFOS caused a minor increase in liver tumor incidence. E2 and PFOA also enhanced MNNG-initiated hepatocarcinogenesis. Pearson correlation analyses, unsupervised hierarchical clustering and principal components analyses showed that the hepatic gene expression profiles for E2 and PFOA, PFNA, PFDA and PFOS were overall highly similar, though distinct patterns of gene expression were evident for each treatment, particularly for PFNA. Conclusions: Overall, these data suggest that multiple PFAAs can promote liver cancer and that the mechanism of promotion may be similar to that for E2.
2011-08-02 | GSE31085 | GEO
Project description:This study aimed to investigate the hepatic transcriptional response of brown trout to glyphosate, and its formulated product, Roundup. We exposed juvenile female brown trout to three concentrations of glyphosate (0.01, 0.5 and 10 mg/L) and Roundup (0.01, 0.5 and 10 mg/L glyphosate acid equivalent) for 14 days and sequenced the hepatic transcriptome of 6 individual females per treatment group in order to determine the global mechanisms of toxicity of this widely used herbicide. We assembled the brown trout transcriptome using an optimised de novo approach, and subsequent differential expression analysis identified a total of 1020 differentially-regulated transcripts across all treatments. Differentially-expressed transcripts included those encoding components of the antioxidant system, a number of stress-response proteins and pro-apoptotic signalling molecules. Functional analysis also revealed over-representation of pathways involved in regulation of cell-proliferation and turnover, and up-regulation of energy metabolism and other metabolic processes. Together, these transcriptional changes are consistent with generation of oxidative stress and the widespread induction of compensatory cellular stress response pathways. The mechanisms of toxicity identified were similar across both glyphosate and Roundup treatments, including for environmentally relevant concentrations. The significant alterations in transcript expression observed at the lowest concentrations tested raises concerns for the toxicity of this herbicide to fish populations inhabiting contaminated rivers. Fish were exposed to 3 concentrations of glyphosate (0.01, 0.1 and 10 mg/L), 3 concentrations of Roundup (0.01, 0.5 and 10 mg/L glyphosate acid equivalent) and water controls for 14 days. Liver mRNA from 6 replicate individuals per treatment was sequenced in an Illumina HiSeq 2500 platform. Two control groups (n=6 fish per group) were included. Using a de novo approach, we assembled the hepatic transcriptome for brown trout. Sequence reads were re-mapped to the assembled transcriptome using Bowtie2 and transcript expression profiling was conducted using EdgeR. ERCC spike controls were added to all individual samples, allowing for the assessment of the reproducibility and dynamic range for transcript expression quantification in our experiments. For the group exposed to 0.1 mg/L glyphosate, only 3 females were available to sequence and the variability between individuals was very high with 1 female identified as an outlier. For this reason, data from this treatment group was deemed unreliable and excluded from the analysis.
2015-04-16 | E-GEOD-56855 | biostudies-arrayexpress
Project description:The study aimed to characterize gene expression in rainbow trout ovary during ovarian development from immature to mature stages. Whole ovary were collected at the following stages: immature pre-vitelogenesis (IMM), mid-vitellogenesis (MV), late vitellogenesis (LV), post-vitellogenesis (PV) and mature while meiotic maturation is in progress (MAT).
2013-04-11 | GSE39587 | GEO
Project description:The study aimed to characterize miRNA expression in rainbow trout ovary during ovarian development from immature to mature stages. Whole ovary were collected at the following stages: immature pre-vitelogenesis (IMM), mid-vitellogenesis (MV), late vitellogenesis (LV), post-vitellogenesis (PV) and mature while meiotic maturation is in progress (MAT).
2013-04-11 | GSE39588 | GEO
Project description:The goal of this study was to identify a set of hepatic genes regulated by ligand-dependent activation of the estrogen receptor in juvenile rainbow trout (Oncorhynchus mykiss) that can serve as a biomarker of estrogen exposure. A custom rainbow trout oligo DNA microarray, which contains probes targeting approximately 1450 genes relevant to carcinogenesis, toxicology, endocrinology and stress physiology was utilized to identify transcriptional “fingerprints” of in vivo dietary exposure to 17β-estradiol (E2), tamoxifen (TAM), estradiol + tamoxifen (E2+TAM), diethylstilbestrol (DES), dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT) and cortisol (CORT). Estrogen exposure altered the expression of up to 49 genes involved in reproduction, immune response, cell growth, transcriptional regulation, protein synthesis and modification, drug metabolism, redox regulation and signal transduction. E2, DES and DHEA regulated 18 genes in common, mostly those associated with vitellogenesis, cell proliferation and signal transduction. Interestingly, DHEA uniquely regulated several complement component genes of importance to immune response. While the effect of TAM on E2-induced changes in gene expression was mostly antagonistic, TAM alone increased expression of VTG1 and other genes associated with egg development and immune response. Few genes responded to CORT treatment, and DHT significantly altered expression of only one gene targeted by the OSUrbt array. Hierarchical cluster and principal components analyses revealed distinct patterns of gene expression corresponding to estrogens and non-estrogens, though unique patterns could also be detected for individual chemicals. A set of estrogen-responsive genes has been identified that can serve as a biomarker of environmental exposure to xenoestrogens. Keywords: estrogen transcriptional profile, chemical transcriptional fingerprint
2007-07-13 | GSE8226 | GEO