Project description:Liver RNA samples from C57BL6 mice drinking Hydrogen water for 4 weeks We used microarrays to detail the gene expression after drinking hydrogen water.
Project description:Arsenic contamination of drinking water occurs globally and is associated with numerous diseases including skin, lung, and bladder cancers, and cardiovascular disease. The mechanisms behind arsenic's effects remain unclear, but recent research indicates that aresnic acts along sex-specific lines and may be an endocrine disruptor. The objective of this study was to evaluate the nature of gene expression chagnes among males and females exposed to arsenic contaminated water in Bangladesh at high and low dose exposures.The median wAs concentration for the low exposure group was 103 µg/L for males and 117 µg/L for females (range 50–200 µg/L). For the high exposure group, the median wAs concentration was 355 µg /L for males (range 250-500 µg /L) and 434 µg/L for females (range 232–1000 µg /L). The PBMCs of males with high exposure compared to those with low exposure there were 534 differentially expressed genes (p <0.05); and for females with high exposure relative to low exposure there were 645 differentially expressed genes (p <0.05) in PBMCs of females.
Project description:Here, we identify persistent and substantial variation in ethanol drinking behavior within an inbred mouse strain and utilize this model to identify gene networks influencing such non-genetic variation in ethanol intake. C57BL/6NCrl mice showed persistent inter-individual variation of ethanol intake in a two-bottle choice paradigm over a three week period, ranging from less than 1 g/kg to over 14 g/kg ethanol in an 18h interval. Whole genome microarray expression analysis in nucleus accumbens, prefrontal cortex and ventral tegmental area of individual animals identified gene expression patterns correlated with ethanol intake. Results included several gene networks previously implicated in ethanol behaviors, such as glutamate signaling, BDNF and genes involved in synaptic vesicle function. Additionally, genes functioning in epigenetic chromatin or DNA modifications such as acetylation and/or methylation also had expression patterns correlated with ethanol intake. Our results thus implicate specific brain regional gene networks, including chromatin modification factors, as potentially important mechanisms underlying individual variation in ethanol intake. Voluntary two-bottle choice drinking was performed as described previously (Khisti et al. 2006). Briefly, two bottles containing 10%(w/v) ethanol (Aaper Alcohol and Chemical Co. Shelbyville, KY) or tap water were placed into the home cage at the beginning of the dark cycle. Tube position was varied every two days (L, L, R, R). Drinking sessions lasted 18 hours/day followed by 6 hours access to water only. Mice had four consecutive drinking sessions followed by four days of abstinence repeated four times to give 16 total drinking sessions. Three brain regions were harvested 6 days after the last drinking session: prefrontal cortex (PFC), nucleus accumbens (NAc) and ventral tegmental area (VTA) as previously described (Kerns et al. 2005). Labeled cRNA from individual animals (n=19) was hybridized to a single microarray for each brain region (n=58 total microarrays).
Project description:Acrylamide is known to produce follicular cell tumors of the thyroid in rats. RccHan Wistar rats were exposed in utero to a carcinogenic dose of acrylamide (3 mg/Kg bw/day) from gestation day 6 to delivery and then through their drinking water to postnatal day 35. In order to identify potential mechanisms of carcinogenesis in the thyroid glands, we used a transcriptomics approach. Thyroid glands were collected from male pups at 10 PM and female pups at 10 AM or 10 PM in order to establish whether active exposure to acrylamide influenced gene expression patterns or pathways that could be related to carcinogenesis. While all animals exposed to acrylamide showed changes in expected target pathways related to carcinogenesis, such as DNA repair, DNA replication, chromosome segregation, among others, animals that were sacrificed while actively drinking acrylamide-laced water during their active period at night showed increased changes in pathways related to oxidative stress, detoxification pathways, metabolism, and activation of checkpoint pathways, among others. In addition, thyroid hormones, T3 and T4, were increased in acrylamide-treated rats sampled at night, but not in quiescent animals, compared to controls. The data clearly indicate that time of day for sample collection is critical to identifying molecular pathways that are altered by the exposures. These results suggest that carcinogenesis in the thyroids of acrylamide treated rats may ensue from several different mechanisms such as hormonal changes and oxidative stress and not only from direct genotoxicity, as has been assumed to date.