Project description:From the results of gene expression analyses of HepG2 under the exposure of 2,3-Dimethoxy-1,4-naphthoquinone (DMNQ), N-nitrosodimethylamine (DMN), phenol and six heavy metals We showed that biological action of six heavy metals were clearly related to that of DMNQ and distinguishable from the other chemicals. These results suggest that oxidative stress is major apparent biological action of high dose heavy metals, supporting the previous reports. Keywords: other
Project description:Heavy metals residue in the natural ecosystem had become one global environmental problem that was eager to solve. Due to the non-biodegradability, organism could deposit excessive heavy metals elements into tissues. Existing literature proposed that prolonged heavy metals enrichment had comprehensive toxicity to multi-organs of vertebrates. However, little research focus on the molecular mechanism for the hepatotoxicity of heavy metal enrichment to Chiroptera. In the present study, ten Hipposideros armiger individuals from Yingde City (YD, relatively pollution-free) and Chunwan City (CW, excessive heavy metals emission) were dissected while environment samples were also obtained. To corroborate the toxicity mechanism of heavy metals to bats liver, multi-omics, pathology and molecular biology methods were performed. Our results showed that more Cd and Pb elements were significantly enriched in bats liver and food sources in the CW group. In addition, prolonged heavy metals accumulation disturbed the hepatic transcription profiling associated with solute carriers family, ribosome pathway, ATP usage and heat shock proteins. Excessive heavy metals enrichment also altered the relative abundance of typical gut microbe taxa to inhibit the tight-junction protein expression. We also found that the levels of superoxide dismutase, glutathione peroxidase and glutathione were decreased while ROS density and malondialdehyde content were elevated after excessive heavy metals enrichment. Besides, hepatic fat accumulation and inflammation injury were also observed under the excessive heavy metals enrichment while the metabolism biomarkers contents were decreased. Therefore, prolonged heavy metals enrichment would induce a series of hepatotoxicity by disturbing the microbes-gut-liver axis and hepatic transcription modes, which could decrease the overall metabolism level in bats. Our study provided protection strategy for biodiversity conservation and raised public attention to environment pollution.
Project description:Environmental contamination from heavy metals poses a global concern for the marine environment, as heavy metals are passed up the food chain and persist in the environment long after the pollution source is contained. Cnidarians, dating back to 700 million years ago, play an important role in shaping marine ecosystems, but environmental pollution profoundly affects their vitality. Among the cnidarians, the sea anemone Nematostella vectensis is an advantageous model for addressing questions in molecular ecology and toxicology as it tolerates extreme environments and its genome has been published. Here we employed a transcriptome-wide RNA-Seq approach to analyze N.vectensis molecular defense mechanisms against four heavy metals: Hg, Cu, Cd and Zn. Altogether, more than 5000 transcripts showed significant changes in gene expression, with Hg having the greatest impact on up-regulating transcripts, followed by Cu, Cd and Zn. We identified, for the first time, co-up-regulation of immediate-early transcription factors such as Egr1, AP1 and NF-κB. Time-course analysis of these genes revealed their early expression as rapidly as one hour after exposure to heavy metals, suggesting that they may complement or substitute for the roles of the metal mediating Mtf1 transcripton factor. We further characterized regulation of a large array of stress-response gene families including Hsp, ABC, CYP members and phytochelatin synthase that may regulate synthesis of the metal-binding phytochelatins instead of the methallothioneins that are absent from Cnidaria genome. This study provides mechanistic insight into heavy-metal toxicity in N.vectensis and sheds light on ancestral stress adaptations.
Project description:The mechanisms of heavy metal accumulation in primary producers and the damage and stress response induced by heavy metals is not well understood. We used UHTS to analyze the transcriptomic response of Elodea nuttallii to heavy metal pollution. We exposed shoots of E. nuttallii for 24 h to increasing concentrations of Hg and Cd. Using Illumina RNA-Seq, we have generated over 50 million 54 nt paired end reads and 14 million single end reads, which we used for de novo assembly of the E. nuttallii transcriptome.
Project description:Environmental contamination from heavy metals poses a global concern for the marine environment, as heavy metals are passed up the food chain and persist in the environment long after the pollution source is contained. Cnidarians, dating back to 700 million years ago, play an important role in shaping marine ecosystems, but environmental pollution profoundly affects their vitality. Among the cnidarians, the sea anemone Nematostella vectensis is an advantageous model for addressing questions in molecular ecology and toxicology as it tolerates extreme environments and its genome has been published. Here we employed a transcriptome-wide RNA-Seq approach to analyze N.vectensis molecular defense mechanisms against four heavy metals: Hg, Cu, Cd and Zn. Altogether, more than 5000 transcripts showed significant changes in gene expression, with Hg having the greatest impact on up-regulating transcripts, followed by Cu, Cd and Zn. We identified, for the first time, co-up-regulation of immediate-early transcription factors such as Egr1, AP1 and NF-κB. Time-course analysis of these genes revealed their early expression as rapidly as one hour after exposure to heavy metals, suggesting that they may complement or substitute for the roles of the metal mediating Mtf1 transcripton factor. We further characterized regulation of a large array of stress-response gene families including Hsp, ABC, CYP members and phytochelatin synthase that may regulate synthesis of the metal-binding phytochelatins instead of the methallothioneins that are absent from Cnidaria genome. This study provides mechanistic insight into heavy-metal toxicity in N.vectensis and sheds light on ancestral stress adaptations. 4 metals were tested in triplicates in comparison to control (4 replicates)
Project description:From the results of gene expression analyses of HepG2 under the exposure of 2,3-Dimethoxy-1,4-naphthoquinone (DMNQ), N-nitrosodimethylamine (DMN), phenol and six heavy metals We showed that biological action of six heavy metals were clearly related to that of DMNQ and distinguishable from the other chemicals. These results suggest that oxidative stress is major apparent biological action of high dose heavy metals, supporting the previous reports. Experiment Overall Design: Using Affymetrix HG-Focus arrays, we compared the gene expression patterns of Hep G2 cells induced by six heavy metals (As, Cd, Ni, Sb, Hg or Cr) with that of DMNQ, DMN or phenol, and evaluated the toxicities of these heavy metals.
Project description:From the result of comparative the gene expression analyses of human hepatoma cell line, HepG2 following exposures of three heavy metals; arsenic, cadmium and nickel and three carcinogens; N-dimethylnitrosoamine (DMN), 12-O-tetradecanoylphorbol-13-acetate (TPA) and tetrachloroethylene (TCE), 31-55% of the genes altered by As, Cd and Ni exposure were overlapped with those by three model carcinogen exposures in our experiments. In particular, three heavy metals shared certain characteristics with TPA and TCE in remarkable up-regulations of the genes associated with progression of cell cycle, which might play a central role in heavy metal carcinogenesis. In addition, this characteristic of gene expressions alteration was counteracted by intracellular accumulation of vitamine C in As-exposed cells but not in Cd- and Ni-exposed cells. These results suggest that the cell proliferative responses are caused by reactive oxygen species mainly in As exposure, while other mechanisms would be involved in these responses in Cd and Ni exposures. Keywords: other