The overall objective of this research is to determine the mechanism by which inorganic arsenic (As)increases human disease risks. The specific goal is to determine the mechanism by which As acts as anendocrine disrupter, which our laboratory first reported and has now demonstrated occurs with severalnuclear hormone receptors via a unique mechanism distinct from that of other known endocrine disrupters.We hypothesize that As-induced endocrine disruption is one of the principal means by which it is able toinfluence the wide array of disease risks including various cancers, diabetes, cardiovascular disease anddevelopmental problems to which it has been linked in epidemiology studies, and that these effects are aresult of As targeting one or more critical regulatory steps that are shared by these receptors, leading in turnto a variety of patho-physiological consequences. We will examine As effects on glucocorticoid receptor(GR)-mediated gene expression in H4IIE and EDR3 rat hepatoma cells as our principal model system,focusing on the differential effects of As on GR signaling at low and intermediate As doses.
Our SpecificAims are to: 1) Determine the effects of very low dose As (0.01-1 u.M, 0.75-75 ppb) to enhance GR-mediatedgene regulation. We hypothesize that these effects are a result of As targeting the early steps in receptoractivation between binding of hormone and activation of transcription. 2) Determine the effects ofintermediate dose As (1-3 |aM, 75-225 ppb) to suppress hormone receptor-mediated gene regulation. Wehypothesize that these effects are distinct from the enhancement seen at lower doses, and involve theintermediate to later steps of receptor-mediated transcription. 3) Determine the effects of endocrinedisruption by As on two hormone-regulated and As-affected genes, TAT and GREB1, that are likely to beinvolved in As-associated disease processes. We will use a combination of confocal microscopy, molecularbiology, biochemistry, and proteomics approaches to investigate these questions. The long-term goals of thisproject are to provide mechanistic insights that can be used for more effective science-based riskassessments, for predicting the specific patho-physiological consequences of As exposure, for assessinggene-environment, agent-agent and other interactions, for assessing specifically sensitive sub-populations atelevated risk, and for developing effective interventions for these As-exposed populations.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Hazardous Substances Basic Research Grants Program (NIEHS) (P42)
Project #
2P42ES007373-14
Application #
7417314
Study Section
Special Emphasis Panel (ZES1-JAB-C (S7))
Project Start
Project End
Budget Start
2008-04-07
Budget End
2009-03-31
Support Year
14
Fiscal Year
2008
Total Cost
$333,372
Indirect Cost
Name
Dartmouth College
Department
Type
DUNS #
041027822
City
Hanover
State
NH
Country
United States
Zip Code
03755
Liu, Maodian; He, Yipeng; Baumann, Zofia et al. (2018) Traditional Tibetan Medicine Induced High Methylmercury Exposure Level and Environmental Mercury Burden in Tibet, China. Environ Sci Technol 52:8838-8847
Taylor, Vivien F; Li, Zhigang; Sayarath, Vicki et al. (2018) Author Correction: Distinct arsenic metabolites following seaweed consumption in humans. Sci Rep 8:4145
Emond, Jennifer A; Karagas, Margaret R; Baker, Emily R et al. (2018) Better Diet Quality during Pregnancy Is Associated with a Reduced Likelihood of an Infant Born Small for Gestational Age: An Analysis of the Prospective New Hampshire Birth Cohort Study. J Nutr 148:22-30
Jackson, Brian P (2018) Low level determination of gallium isotopes by ICP-QQQ. J Anal At Spectrom 33:897-900
Nachman, Keeve E; Punshon, Tracy; Rardin, Laurie et al. (2018) Opportunities and Challenges for Dietary Arsenic Intervention. Environ Health Perspect 126:84503
Koutros, Stella; Baris, Dalsu; Waddell, Richard et al. (2018) Potential effect modifiers of the arsenic-bladder cancer risk relationship. Int J Cancer 143:2640-2646
Liu, Maodian; Chen, Long; He, Yipeng et al. (2018) Impacts of farmed fish consumption and food trade on methylmercury exposure in China. Environ Int 120:333-344
Hampton, Thomas H; Jackson, Craig; Jung, Dawoon et al. (2018) Arsenic Reduces Gene Expression Response to Changing Salinity in Killifish. Environ Sci Technol 52:8811-8821
Caito, Samuel W; Jackson, Brian P; Punshon, Tracy et al. (2018) Editor's Highlight: Variation in Methylmercury Metabolism and Elimination Status in Humans Following Fish Consumption. Toxicol Sci 161:443-453
Ricachenevsky, Felipe K; Punshon, Tracy; Lee, Sichul et al. (2018) Elemental Profiling of Rice FOX Lines Leads to Characterization of a New Zn Plasma Membrane Transporter, OsZIP7. Front Plant Sci 9:865

Showing the most recent 10 out of 372 publications