Project description:Juvenile zebrafish were fed Biodiet starter (4% body weight per day) for 42 d with TCDD added at 0 ppb, 0.1 ppb, 1 ppb, 10 ppb or 100 ppb. Fish were collected, sexed, weighed and length measured at 0, 7, 14, 28 or 42 d for TCDD assessment, histopathologic and microarray analysis. Microarray experiments were conducted using 0 and 100 ppb-TCDD treated male and female sexed zebrafish at 7, 14, 28 and 42 d. NimbleGen Gene Expression 12X135K zebrafish microarrays and One-Color DNA labeling Kit (NimbleGen, WI) were used for genome-wide expression analysis of TCDD-treated zebrafish. TCDD accumulated in a dose- and time-dependent manner and 100 ppb TCDD caused TCDD accumulation in female (15.49 ppb) and male (18.04 ppb) fish at 28 d post exposure. TCDD caused multiple lesions in liver, kidney, intestine and ovary of zebrafish and functional dysregulation such as depletion of glycogen in liver, retrobulbar edema, degeneration of neurosensory epithelium, underdevelopment of intestine, and diminution in the fraction of ovarian follicles containing vitellogenic oocytes. At 42d, no mature female fish were observed.
Project description:Juvenile zebrafish were fed Biodiet starter (4% body weight per day) for 42 d with TCDD added at 0 ppb, 0.1 ppb, 1 ppb, 10 ppb or 100 ppb. Fish were collected, sexed, weighed and length measured at 0, 7, 14, 28 or 42 d for TCDD assessment, histopathologic and microarray analysis. Microarray experiments were conducted in TCDD-treated (at 0, 0.1, 1, 10 and 100 ppb) for male and female sexed zebrafish at 28 d. NimbleGen Gene Expression 12X135K zebrafish microarrays and One-Color DNA labeling Kit (NimbleGen, WI) were used for genome-wide expression analysis of TCDD-treated zebrafish. TCDD accumulated in a dose- and time-dependent manner and 100 ppb TCDD caused TCDD accumulation in female (15.49 ppb) and male (18.04 ppb) fish at 28 d post exposure. TCDD caused multiple lesions in liver, kidney, intestine and ovary of zebrafish and functional dysregulation such as depletion of glycogen in liver, retrobulbar edema, degeneration of neurosensory epithelium, underdevelopment of intestine, and diminution in the fraction of ovarian follicles containing vitellogenic oocytes. Microarray gene expression analysis comparing control to post TCDD diet revealed dysregulated genes located in pathways associated with cardiac necrosis/cell death, cardiac fibrosis, renal necrosis/cell death and liver necrosis/cell death. These baseline toxicological effects provide evidence for the potential biomarkers, mechanisms and pathology of TCDD induced dysregulation.
Project description:We investigated the effects of chronic TCDD exposure on global gene expression in developing rainbow trout (Oncorhynchus mykiss). Juvenile rainbow trout(0.18±0.01g) were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100ppb, and ten fish were sampled and pooled from 10 ppb group at 7, 14, 28 and 42 days for microarray experiments after initiation of the exposure. Gene expression analysis was performed using the Genomics Research on All Salmonids Project (cGRASP) 16K cDNA microarrays. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including response to stimulus, cell wall organization or biogenesis, growth and cell proliferation. In addition, TCDD caused leisons in multiple organ systems in juvenile rainbow, including skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney.
Project description:We investigated the effects of chronic TCDD exposure on global gene expression in developing rainbow trout (Oncorhynchus mykiss). Juvenile rainbow trout(0.18M-BM-10.01g) were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100ppb, and ten fish were sampled and pooled from 10 ppb group at 7, 14, 28 and 42 days for microarray experiments after initiation of the exposure. Gene expression analysis was performed using the Genomics Research on All Salmonids Project (cGRASP) 16K cDNA microarrays. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including response to stimulus, cell wall organization or biogenesis, growth and cell proliferation. In addition, TCDD caused leisons in multiple organ systems in juvenile rainbow, including skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. Juvenile rainbow trout (0.18M-BM-10.01g) were fed Biodiet starter (Bio-Oregon) (4% body weight per day) with TCDD added at 0, 0.1, 1, 10 and 100 ppb. Fish were sampled and from 10 ppb group at 7, 14, 28 and 42 days for microarray experiments after initiation of the exposure. Total RNA from individual fish was isolated using TRIzol reagent (Invitrogen).Total RNA of ten control trout were pooled as a common reference which were labeled with Cy3. Total RNA of ten fish of each treatment were labeled wih Cy5. cDNA were synthesized using SuperScript II Reverse Transcriptase (Invitrogen) (1 M-NM-<g pooled RNA per synthesis). Targets were labeled using the Array 900 Expression Array Detection kit (Genisphere) following the manufacture protocol. 1M-BM-5g RNA of pooled ten control fish were labled with Cy3 and 1M-BM-5g RNA of pooled ten TCDD-treated fish were labled with Cy5, then day-swap was performed. Two arrays were run for each comparison. Microarrays were scanned at 10 M-BM-5m resolution using a ScanArray Express (PerkinElmer Life Sciences, Inc, Boston, MA). The photomultiplier tube settings (PMT) for Cy3 and Cy5 were 70 and 65-66, respectively. TIFF images of arrays were generated with ScanArray Express software (PerkinElmer). Fluorescence intensity data for Cy3 and Cy5 channels were extracted from TIFF images using ImaGene 7.5 software (BioDiscovery Inc., El Segundo, CA). Background correction, data transformation (setting background corrected values < 0.01 to 0.01), Lowess normalization, and analysis (e.g. fold-change calculations) were performed using GeneSpring GX 7.3 (Agilent Technologies, Palo Alto, CA)