1
|
Rai PK, Sonne C, Kim KH. Heavy metals and arsenic stress in food crops: Elucidating antioxidative defense mechanisms in hyperaccumulators for food security, agricultural sustainability, and human health. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 874:162327. [PMID: 36813200 DOI: 10.1016/j.scitotenv.2023.162327] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 02/02/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
The spread of heavy metal(loid)s at soil-food crop interfaces has become a threat to sustainable agricultural productivity, food security, and human health. The eco-toxic effects of heavy metals on food crops can be manifested through reactive oxygen species that have the potential to disturb seed germination, normal growth, photosynthesis, cellular metabolism, and homeostasis. This review provides a critical overview of stress tolerance mechanisms in food crops/hyperaccumulator plants against heavy metals and arsenic (HM-As). The HM-As antioxidative stress tolerance in food crops is associated with changes in metabolomics (physico-biochemical/lipidomics) and genomics (molecular level). Furthermore, HM-As stress tolerance can occur through plant-microbe, phytohormone, antioxidant, and signal molecule interactions. Information regarding the avoidance, tolerance, and stress resilience of HM-As should help pave the way to minimize food chain contamination, eco-toxicity, and health risks. Advanced biotechnological approaches (e.g., genome modification with CRISPR-Cas9 gene editing) in concert with traditional sustainable biological methods are useful options to develop 'pollution safe designer cultivars' with increased climate change resilience and public health risks mitigation. Further, the usage of HM-As tolerant hyperaccumulator biomass in biorefineries (e.g., environmental remediation, value added chemicals, and bioenergy) is advocated to realize the synergy between biotechnological research and socio-economic policy frameworks, which are inextricably linked with environmental sustainability. The biotechnological innovations, if directed toward 'cleaner climate smart phytotechnologies' and 'HM-As stress resilient food crops', should help open the new path to achieve sustainable development goals (SDGs) and a circular bioeconomy.
Collapse
Affiliation(s)
- Prabhat Kumar Rai
- Department of Environmental Science, Mizoram University, Aizawl 796004, India
| | - Christian Sonne
- Department of Ecoscience, Aarhus University, Frederiksborgvej 399, PO Box 358, DK-4000 Roskilde, Denmark
| | - Ki-Hyun Kim
- Department of Civil & Environmental Engineering, Hanyang University, 222 Wangsimni-Ro, Seoul 04763, Republic of Korea.
| |
Collapse
|
2
|
Amolegbe SM, Carlin DJ, Henry HF, Heacock ML, Trottier BA, Suk WA. Understanding exposures and latent disease risk within the National Institute of Environmental Health Sciences Superfund Research Program. Exp Biol Med (Maywood) 2022; 247:529-537. [PMID: 35253496 DOI: 10.1177/15353702221079620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Understanding the health effects of exposures when there is a lag between exposure and the onset of disease is an important and challenging topic in environmental health research. The National Institute of Environmental Health Sciences (NIEHS) Superfund Basic Research and Training Program (SRP) is a National Institutes of Health (NIH) grant program that uses a multidisciplinary approach to support biomedical and environmental science and engineering research. Because of the multidisciplinary nature of the program, SRP grantees are well-positioned to study exposure and latent disease risk across humans, animal models, and various life stages. SRP-funded scientists are working to address the challenge of connecting exposures that occur early in life and prior to conception with diseases that manifest much later, including developing new tools and approaches to predict how chemicals may affect long-term health. Here, we highlight research from the SRP focused on understanding the health effects of exposures with a lag between exposure and the onset of the disease as well as provide future directions for addressing knowledge gaps for this highly complex and challenging topic. Advancing the knowledge of latency to disease will require a multidisciplinary approach to research, the need for data sharing and integration, and new tools and computation approaches to make better predications about the timing of disease onset. A better understanding of exposures that may contribute to later-life diseases is essential to supporting the implementation of prevention and intervention strategies to reduce or modulate exposures to reduce disease burden.
Collapse
Affiliation(s)
- Sara M Amolegbe
- Superfund Research Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, NC 27560, USA
| | - Danielle J Carlin
- Superfund Research Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, NC 27560, USA
| | - Heather F Henry
- Superfund Research Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, NC 27560, USA
| | - Michelle L Heacock
- Superfund Research Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, NC 27560, USA
| | - Brittany A Trottier
- Superfund Research Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, NC 27560, USA
| | - William A Suk
- Superfund Research Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, NC 27560, USA
| |
Collapse
|
3
|
Hsu KS, Goodale BC, Ely KH, Hampton TH, Stanton BA, Enelow RI. Single-cell RNA-seq Analysis Reveals That Prenatal Arsenic Exposure Results in Long-term, Adverse Effects on Immune Gene Expression in Response to Influenza A Infection. Toxicol Sci 2021; 176:312-328. [PMID: 32514536 DOI: 10.1093/toxsci/kfaa080] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Arsenic exposure via drinking water is a serious environmental health concern. Epidemiological studies suggest a strong association between prenatal arsenic exposure and subsequent childhood respiratory infections, as well as morbidity from respiratory diseases in adulthood, long after systemic clearance of arsenic. We investigated the impact of exclusive prenatal arsenic exposure on the inflammatory immune response and respiratory health after an adult influenza A virus (IAV) lung infection. C57BL/6J mice were exposed to 100 ppb sodium arsenite in utero, and subsequently infected with IAV (H1N1) after maturation to adulthood. Assessment of lung tissue and bronchoalveolar lavage fluid at various time points post-IAV infection reveals greater lung damage and inflammation in arsenic-exposed mice versus control mice. Single-cell RNA sequencing analysis of immune cells harvested from IAV-infected lungs suggests that the enhanced inflammatory response is mediated by dysregulation of innate immune function of monocyte-derived macrophages, neutrophils, natural killer cells, and alveolar macrophages. Our results suggest that prenatal arsenic exposure results in lasting effects on the adult host innate immune response to IAV infection, long after exposure to arsenic, leading to greater immunopathology. This study provides the first direct evidence that exclusive prenatal exposure to arsenic in drinking water causes predisposition to a hyperinflammatory response to IAV infection in adult mice, which is associated with significant lung damage.
Collapse
Affiliation(s)
- Kevin S Hsu
- Guarini School of Graduate and Advanced Studies at Dartmouth College, Hanover, New Hampshire 03755.,Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03766
| | - Britton C Goodale
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03766.,Dartmouth Toxic Metals Superfund Research Program, Hanover, New Hampshire 03755
| | - Kenneth H Ely
- Department of Medicine, Dartmouth-Hitchcock, Lebanon, New Hampshire 03766
| | - Thomas H Hampton
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03766
| | - Bruce A Stanton
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03766.,Dartmouth Toxic Metals Superfund Research Program, Hanover, New Hampshire 03755
| | - Richard I Enelow
- Guarini School of Graduate and Advanced Studies at Dartmouth College, Hanover, New Hampshire 03755.,Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth College, Lebanon, New Hampshire 03766.,Dartmouth Toxic Metals Superfund Research Program, Hanover, New Hampshire 03755.,Department of Medicine, Dartmouth-Hitchcock, Lebanon, New Hampshire 03766
| |
Collapse
|
4
|
Chakraborty M, Bhaumik M. Prenatal arsenic exposure interferes in postnatal immunocompetence despite an absence of ongoing arsenic exposure. J Immunotoxicol 2021; 17:135-143. [PMID: 32538211 DOI: 10.1080/1547691x.2020.1767238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Arsenic (As) readily crosses the placenta and exposure of the fetus may cause adverse consequences later in life, including immunomodulation. In the current study, the question was asked how the immune repertoire might respond in postnatal life when there is no further As exposure. Here, pregnant mice (Balb/c [H-2d]) were exposed to arsenic trioxide (As2O3) through their drinking water from time of conception until parturition. Their offspring, 4-week-old mice who had not been exposed again to As, were used for functional analyses of innate, humoral and cellular immunity. Compared to cells from non-As-exposed dam offspring, isolated peritoneal macro-phages (Mϕ) displayed no differences in T-cell stimulating ability. Levels of circulating IgG2a but not IgG1 were decreased in As-exposed dam offspring as compared to control offspring counterparts. Mixed-leukocyte reactions (MLR) indicated that CD4+ T-cells from the prenatal As-exposed mice were significantly less responsive to allogenic stimulation as evidenced by decreases in interferon (IFN)-γ and IL-2 production and in expression of CD44 and CD69 (but not CD25) activation markers. Interestingly, the Mϕ from the prenatal As-exposed mice were capable of stimulating normal allogenic T-cells, indicating that T-cells from these mice were refractory to allogenic signals. There was also a significant decrease in absolute numbers of splenic CD4+ and CD8+ T-cells due to prenatal As exposure (as compared to control). Lastly, the impaired immune function of the prenatal As-exposed mice was correlated with a very strong susceptibility to Escherichia coli infection. Taken together, the data from this study clearly show that in utero As exposure may continue to perpetuate a dampening effect on the immune repertoire of offspring, even into the early stages of postnatal life.
Collapse
Affiliation(s)
- Mainak Chakraborty
- Division of Immunology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Moumita Bhaumik
- Division of Immunology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| |
Collapse
|
5
|
Negro Silva LF, Makhani K, Lemaire M, Lemarié CA, Plourde D, Bolt AM, Chiavatti C, Bohle DS, Lehoux S, Goldberg MS, Mann KK. Sex-Specific Effects of Prenatal and Early Life Inorganic and Methylated Arsenic Exposure on Atherosclerotic Plaque Development and Composition in Adult ApoE-/- Mice. ENVIRONMENTAL HEALTH PERSPECTIVES 2021; 129:57008. [PMID: 34014776 PMCID: PMC8136521 DOI: 10.1289/ehp8171] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 02/26/2021] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Epidemiologic studies indicate that early life arsenic exposures are linked to an increased risk of cardiovascular diseases. Different oxidation and methylation states of arsenic exist in the environment and are formed in vivo via the action of arsenic (+3 oxidation state) methyltransferase (As3MT). Methylated arsenicals are pro-atherogenic postnatally, but pre- and perinatal effects are unclear. This is particularly important because methylated arsenicals are known to cross the placenta. OBJECTIVES We tested the effects of early life exposure to inorganic and methylated arsenicals on atherosclerotic plaque formation and its composition in apolipoprotein E knock-out (apoE-/-) mice and evaluated whether apoE-/- mice lacking As3MT expression were susceptible to this effect. METHODS We exposed apoE-/- or apoE-/-/As3MT-/- mice to 200 ppb inorganic or methylated arsenic in the drinking water from conception to weaning and assessed atherosclerotic plaques in the offspring at 18 wk of age. Mixed regression models were used to estimate the mean difference in each outcome relative to controls, adjusting for sex and including a random effects term to account for within-litter clustering. RESULTS Early life exposure to inorganic arsenic, and more profoundly methylated arsenicals, resulted in significantly larger plaques in the aortic arch and sinus in both sexes. Lipid levels in these plaques were higher without a substantial difference in macrophage numbers. Smooth muscle cell content was not altered, but collagen content was lower. Importantly, there were sex-specific differences in these observations, where males had higher lipids and lower collagen in the plaque, but females did not. In mice lacking As3MT, arsenic did not alter the plaque size, although the size was highly variable. In addition, control apoE-/-/As3MT-/- mice had significantly larger plaque size compared with control apoE-/-. CONCLUSION This study shows that early life exposure to inorganic and methylated arsenicals is pro-atherogenic with sex-specific differences in plaque composition and a potential role for As3MT in mice. https://doi.org/10.1289/EHP8171.
Collapse
Affiliation(s)
| | - Kiran Makhani
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| | - Maryse Lemaire
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| | - Catherine A. Lemarié
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
- EA3878, European University of Occidental Brittany, Brest, France
- UMR 1078, Institut national de la santé et de la recherché médicale, Brest, France
| | - Dany Plourde
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| | - Alicia M. Bolt
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| | - Christopher Chiavatti
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| | - D. Scott Bohle
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Stéphanie Lehoux
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| | - Mark S. Goldberg
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada
- Division of Clinical Epidemiology, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Koren K. Mann
- Lady Davis Institute for Medical Research, McGill University, Montreal, Quebec, Canada
| |
Collapse
|
6
|
Bantol KEA, Brumberg HL, Shah SI, Javier JR. Perspectives from the Society for Pediatric Research: contaminants of water and children's health: Can we do better? Pediatr Res 2020; 88:535-543. [PMID: 32470969 DOI: 10.1038/s41390-020-0985-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 02/18/2020] [Accepted: 04/29/2020] [Indexed: 01/09/2023]
Abstract
Children are uniquely susceptible to the health consequences of water contamination. In this review, we summarize the existing, robust literature supporting the importance of examining specific water contaminants (i.e., lead, pesticides, nitrates, arsenic, perchlorate) and the routes of contamination in the United States and globally. We also discuss the health effects of exposure to contaminated water and significant disparities related to access to clean water. Lastly, we offer strategies for prevention and intervention-including those focused on the individual patient level-and review the current US policy framework pertaining to regulation of these toxicants. IMPACT: A key message in this article is that exposure to water contaminants have serious and long-lasting consequences on children's health. This review summarizes current existing literature and adds policy recommendations supporting clean water for children. Information from this review has two potential impacts: Guide health professionals in screening and/or treating children's health problems resulting from water contaminant exposure. Guide policy makers in using evidence-based approaches to improve water quality and clean water access.
Collapse
Affiliation(s)
- Kamil Evy A Bantol
- Division of General Pediatrics, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Heather L Brumberg
- New York Medical College, Maria Fareri Children's Hospital at Westchester Medical Center, New York, NY, USA
| | - Shetal I Shah
- New York Medical College, Maria Fareri Children's Hospital at Westchester Medical Center, New York, NY, USA
| | - Joyce R Javier
- Division of General Pediatrics, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
7
|
Xie L, Hu WY, Hu DP, Shi G, Li Y, Yang J, Prins GS. Effects of Inorganic Arsenic on Human Prostate Stem-Progenitor Cell Transformation, Autophagic Flux Blockade, and NRF2 Pathway Activation. ENVIRONMENTAL HEALTH PERSPECTIVES 2020; 128:67008. [PMID: 32525701 PMCID: PMC7289393 DOI: 10.1289/ehp6471] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 03/18/2020] [Accepted: 05/06/2020] [Indexed: 05/26/2023]
Abstract
BACKGROUND Inorganic arsenic (iAs) is an environmental toxicant associated with an increased risk of prostate cancer in chronically exposed populations worldwide. However, the biological mechanisms underlying iAs-induced prostate carcinogenesis remain unclear. OBJECTIVES We studied how iAs affects normal human prostate stem-progenitor cells (PrSPCs) and drives transformation and interrogated the molecular mechanisms involved. METHODS PrSPCs were enriched by spheroid culture from normal human primary or immortalized prostate epithelial cells, and their differentiation capability was evaluated by organoid culture. Microarray analysis was conducted to identify iAs-dysregulated genes, and lentiviral infection was used for stable manipulation of identified genes. Soft agar colony growth assays were applied to examine iAs-induced transformation. For in vivo study, PrSPCs mixed with rat urogenital sinus mesenchyme were grafted under the renal capsule of nude mice to generate prostatelike tissues, and mice were exposed to 5 ppm (∼65μM) iAs in drinking water for 3 months. RESULTS Low-dose iAs (1μM) disturbed PrSPC homeostasis in vitro, leading to increased self-renewal and suppressed differentiation. Transcriptomic analysis indicated that iAs activated oncogenic pathways in PrSPCs, including the KEAP1-NRF2 pathway. Further, iAs-exposed proliferative progenitor cells exhibited NRF2 pathway activation that was sustained in their progeny cells. Knockdown of NRF2 inhibited spheroid formation by driving PrSPC differentiation, whereas its activation enhanced spheroid growth. Importantly, iAs-induced transformation was suppressed by NRF2 knockdown. Mechanistically, iAs suppressed Vacuolar ATPase subunit VMA5 expression, impairing lysosome acidification and inhibiting autophagic protein degradation including p62, which further activated NRF2. In vivo, chronic iAs exposure activated NRF2 in both epithelial and stroma cells of chimeric human prostate grafts and induced premalignant events. CONCLUSIONS Low-dose iAs increased self-renewal and decreased differentiation of human PrSPCs by activating the p62-NRF2 axis, resulting in epithelial cell transformation. NRF2 is activated by iAs through specific autophagic flux blockade in progenitor cells, which may have potential therapeutic implications. https://doi.org/10.1289/EHP6471.
Collapse
Affiliation(s)
- Lishi Xie
- Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
- Chicago Center for Health and Environment, Chicago, Illinois, USA
| | - Wen-Yang Hu
- Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
- Chicago Center for Health and Environment, Chicago, Illinois, USA
| | - Dan-Ping Hu
- Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Guangbin Shi
- Division of Cardiothoracic Surgery, The Warren Alpert Medical School of Brown University, Rhode Island Hospital, Providence, Rhode Island, USA
| | - Ye Li
- Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Jianfu Yang
- Department of Urology, The Third Xiangya Hospital of Central South University, Changsha, Hunan, People’s Republic of China
| | - Gail S. Prins
- Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
- Chicago Center for Health and Environment, Chicago, Illinois, USA
- Departments of Physiology & Biophysics and Pathology, College of Medicine; Division of Epidemiology & Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, Illinois, USA
- University of Illinois Cancer Center, Chicago, Illinois, USA
| |
Collapse
|
8
|
Exposure to low doses of inorganic arsenic induces transgenerational changes on behavioral and epigenetic markers in zebrafish (Danio rerio). Toxicol Appl Pharmacol 2020; 396:115002. [PMID: 32277946 DOI: 10.1016/j.taap.2020.115002] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/26/2020] [Accepted: 04/07/2020] [Indexed: 02/06/2023]
Abstract
The ability of environmental pollutants to alter the epigenome with resultant development of behavioral alterations has received more attention in recent years. These alterations can be transmitted and affect later generations that have not been directly in contact with the contaminant. Arsenic (As) is a neurotoxicant and potent epigenetic disruptor that is widespread in the environment; however, the precise potential of As to produce transgenerational effects is unknown. Our study focused on the possible transgenerational effects on behavior by ancestral exposure to doses relevant to the environment of As, and the epigenetic mechanisms that could be involved. Embryos of F0 (ancestral generation) were directly exposed to 50 or 500 ppb of As for 150 days. F0 adults were raised to produce the F1 generation (intergeneration) and subsequently the F2 generation (transgeneration). We evaluated motor and cognitive behavior, neurodevelopment-related genes, and epigenetic markers on the F0 and F2 generation. As proposed in our hypothesis, ancestral arsenic exposure altered motor activity through the development and increased anxiety-like behaviors which were transmitted to the F2 generation. Additionally, we found a reduction in brain-derived neurotrophic factor expression between the F0 and F2 generation, and an increase in methylation on histone H3K4me3 in the nervous system.
Collapse
|
9
|
Potential facet for prenatal arsenic exposure paradigm: linking endocrine disruption and epigenetics. THE NUCLEUS 2019. [DOI: 10.1007/s13237-019-00274-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
|
10
|
Transplacental exposure to carcinogens and risks to children: evidence from biomarker studies and the utility of omic profiling. Arch Toxicol 2019; 93:833-857. [PMID: 30859261 DOI: 10.1007/s00204-019-02428-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/04/2019] [Indexed: 12/12/2022]
Abstract
The factors underlying the increasing rates and the geographic variation of childhood cancers are largely unknown. Epidemiological studies provide limited evidence for a possible role in the etiology of certain types of childhood cancer of the exposure of pregnant women to environmental carcinogens (e.g., tobacco smoke and pesticides); however, such evidence is inadequate to allow definitive conclusions. Complementary evidence can be obtained from biomarker-based population studies. Such studies have demonstrated that, following exposure of pregnant mothers, most environmental carcinogens reach the fetus and, in many cases, induce therein genotoxic damage which in adults is known to be associated with increased cancer risk, implying that environmental carcinogens may contribute to the etiology of childhood cancer. During recent years, intermediate disease biomarkers, obtained via omic profiling, have provided additional insights into the impact of transplacental exposures on fetal tissues which, in some cases, are also compatible with a precarcinogenic role of certain in utero exposures. Here we review the epidemiological and biomarker evidence and discuss how further research, especially utilizing high-density profiling, may allow a better evaluation of the links between in utero environmental exposures and cancer in children.
Collapse
|
11
|
Schwalfenberg G, Rodushkin I, Genuis SJ. Heavy metal contamination of prenatal vitamins. Toxicol Rep 2018; 5:390-395. [PMID: 29854609 PMCID: PMC5978005 DOI: 10.1016/j.toxrep.2018.02.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 02/25/2018] [Accepted: 02/27/2018] [Indexed: 12/18/2022] Open
Abstract
Toxic elements are found in prenatal vitamins with lead at unacceptable levels in more than half of the products tested. Arsenic is also found in some products at unsafe levels. Thallium is present at levels in some products that are not acceptable. Some products have very low level, which are safer, and recommendations are made to have industry (self regulatory) and government oversight to have the least contamination of prenatal vitamins.
Prenatal vitamins are often consumed daily during gestation and postnatally for up to 18–24 months with the belief that supplementation achieves better outcomes. Detrimental effects of gestational exposure to adverse chemical agents are gathering increasing attention. This study was designed to assess toxic element contamination in prenatal supplements. Twenty-six commonly used prenatal vitamin brands including one prescription brand were collected from Canadian health-food outlets and pharmacies, and tested for toxic element contamination. Results were compared to established endpoints. All samples contained Lead with average amounts being (0.535 μgm), 20/51 samples exceeded established standards for lead toxicity (0.50 μgm/day), with one sample yielding 4. μgm/day. Three samples registered inorganic arsenic levels above acceptable limits. Cadmium levels did not exceed current standards. Toxic elements such as Aluminum, Nickel, Titanium and Thallium were detected in all samples. Cumulative intake of prenatal supplement over many months may constitute a significant source of toxic element exposure to the mother and offspring. With several samples exceeding known standards for gestational toxic element exposure, guidelines for routine monitoring and reporting are required. In keeping with recommendations from the International Federation of Obstetrics and Gynecology, industry regulation would be welcomed to protect expectant mothers and their vulnerable offspring.
Collapse
Affiliation(s)
| | - Ilia Rodushkin
- Scandinavia Division of A.L.S. Laboratory Group, Sweden.,Luleå University of Technology, Sweden
| | - Stephen J Genuis
- Department of Obstetrics and Gynecology, University of Alberta, Canada
| |
Collapse
|
12
|
Kryeziu K, Pirker C, Englinger B, van Schoonhoven S, Spitzwieser M, Mohr T, Körner W, Weinmüllner R, Tav K, Grillari J, Cichna-Markl M, Berger W, Heffeter P. Chronic arsenic trioxide exposure leads to enhanced aggressiveness via Met oncogene addiction in cancer cells. Oncotarget 2017; 7:27379-93. [PMID: 27036042 PMCID: PMC5053657 DOI: 10.18632/oncotarget.8415] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/18/2016] [Indexed: 01/02/2023] Open
Abstract
As an environmental poison, arsenic is responsible for many cancer deaths. Paradoxically, arsenic trioxide (ATO) presents also a powerful therapy used to treat refractory acute promyelocytic leukemia (APL) and is intensively investigated for treatment of other cancer types. Noteworthy, cancer therapy is frequently hampered by drug resistance, which is also often associated with enhancement of tumor aggressiveness. In this study, we analyzed ATO-selected cancer cells (A2780ATO) for the mechanisms underlying their enhanced tumorigenicity and aggressiveness. These cells were characterized by enhanced proliferation and spheroid growth as well as increased tumorigenicity of xenografts in SCID mice. Noteworthy, subsequent studies revealed that overexpression of Met receptor was the underlying oncogenic driver of these effects, as A2780ATO cells were characterized by collateral sensitivity against Met inhibitors. This finding was also confirmed by array comparative genomic hybridization (array CGH) and whole genome gene expression arrays, which revealed that Met overexpression by chronic ATO exposure was based on the transcriptional regulation via activation of AP-1. Finally, it was shown that treatment with the Met inhibitor crizotinib was also effective against A2780ATO cell xenografts in vivo, indicating that targeting of Met presents a promising strategy for the treatment of Met-overexpressing tumors after either arsenic exposure or failure to ATO treatment.
Collapse
Affiliation(s)
- Kushtrim Kryeziu
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria.,Research Platform "Translational Cancer Therapy Research", Vienna, Austria
| | - Christine Pirker
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria
| | - Bernhard Englinger
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria
| | - Sushilla van Schoonhoven
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria
| | | | - Thomas Mohr
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria
| | - Wilfried Körner
- Department of Environmental Geosciences, University of Vienna, Vienna, Austria
| | - Regina Weinmüllner
- Christian Doppler Laboratory on Biotechnology of Skin Aging, Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - Koray Tav
- Christian Doppler Laboratory on Biotechnology of Skin Aging, Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - Johannes Grillari
- Christian Doppler Laboratory on Biotechnology of Skin Aging, Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Vienna, Austria.,Evercyte GmbH, Vienna, Austria
| | | | - Walter Berger
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria.,Research Platform "Translational Cancer Therapy Research", Vienna, Austria
| | - Petra Heffeter
- Department of Medicine I, Institute of Cancer Research and Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria.,Research Platform "Translational Cancer Therapy Research", Vienna, Austria
| |
Collapse
|
13
|
Beaver LM, Truong L, Barton CL, Chase TT, Gonnerman GD, Wong CP, Tanguay RL, Ho E. Combinatorial effects of zinc deficiency and arsenic exposure on zebrafish (Danio rerio) development. PLoS One 2017; 12:e0183831. [PMID: 28837703 PMCID: PMC5570330 DOI: 10.1371/journal.pone.0183831] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2017] [Accepted: 08/11/2017] [Indexed: 11/19/2022] Open
Abstract
Zinc deficiency and chronic low level exposures to inorganic arsenic in drinking water are both significant public health concerns that affect millions of people including pregnant women. These two conditions can co-exist in the human population but little is known about their interaction, and in particular, whether zinc deficiency sensitizes individuals to arsenic exposure and toxicity, especially during critical windows of development. To address this, we utilized the Danio rerio (zebrafish) model to test the hypothesis that parental zinc deficiency sensitizes the developing embryo to low-concentration arsenic toxicity, leading to altered developmental outcomes. Adult zebrafish were fed defined zinc deficient and zinc adequate diets and were spawned resulting in zinc adequate and zinc deficient embryos. The embryos were treated with environmentally relevant concentrations of 0, 50, and 500 ppb arsenic. Arsenic exposure significantly reduced the amount of zinc in the developing embryo by ~7%. The combination of zinc deficiency and low-level arsenic exposures did not sensitize the developing embryo to increased developmental malformations or mortality. The combination did cause a 40% decline in physical activity of the embryos, and this decline was significantly greater than what was observed with zinc deficiency or arsenic exposure alone. Significant changes in RNA expression of genes that regulate zinc homeostasis, response to oxidative stress and insulin production (including zip1, znt7, nrf2, ogg1, pax4, and insa) were found in zinc deficient, or zinc deficiency and arsenic exposed embryos. Overall, the data suggests that the combination of zinc deficiency and arsenic exposure has harmful effects on the developing embryo and may increase the risk for developing chronic diseases like diabetes.
Collapse
Affiliation(s)
- Laura M. Beaver
- Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, United States of America
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, United States of America
| | - Lisa Truong
- Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, Oregon, United States of America
- The Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon, United States of America
| | - Carrie L. Barton
- Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, Oregon, United States of America
- The Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon, United States of America
| | - Tyler T. Chase
- Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, United States of America
| | - Greg D. Gonnerman
- Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, Oregon, United States of America
- The Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon, United States of America
| | - Carmen P. Wong
- Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, United States of America
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, United States of America
| | - Robert L. Tanguay
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, United States of America
- Department of Environmental and Molecular Toxicology, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, Oregon, United States of America
- The Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon, United States of America
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, United States of America
| | - Emily Ho
- Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, United States of America
- Linus Pauling Institute, Oregon State University, Corvallis, Oregon, United States of America
- The Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon, United States of America
- Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, United States of America
- Moore Family Center for Whole Grain Foods, Nutrition and Preventive Health, Oregon State University, Corvallis, Oregon, United States of America
| |
Collapse
|
14
|
Bommarito PA, Martin E, Fry RC. Effects of prenatal exposure to endocrine disruptors and toxic metals on the fetal epigenome. Epigenomics 2017. [PMID: 28234024 DOI: 10.2217/epi-20160112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023] Open
Abstract
Exposure to environmental contaminants during pregnancy has been linked to adverse outcomes at birth and later in life. The link between prenatal exposures and latent health outcomes suggests that these exposures may result in long-term epigenetic reprogramming. Toxic metals and endocrine disruptors are two major classes of contaminants that are ubiquitously present in the environment and represent threats to human health. In this review, we present evidence that prenatal exposures to these contaminants result in fetal epigenomic changes, including altered global DNA methylation, gene-specific CpG methylation and microRNA expression. Importantly, these changes may have functional cellular consequences, impacting health outcomes later in life. Therefore, these epigenetic changes represent a critical mechanism that warrants further study.
Collapse
Affiliation(s)
- Paige A Bommarito
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Elizabeth Martin
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rebecca C Fry
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Curriculum in Toxicology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, USA
| |
Collapse
|
15
|
Bommarito PA, Martin E, Fry RC. Effects of prenatal exposure to endocrine disruptors and toxic metals on the fetal epigenome. Epigenomics 2017; 9:333-350. [PMID: 28234024 DOI: 10.2217/epi-2016-0112] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Exposure to environmental contaminants during pregnancy has been linked to adverse outcomes at birth and later in life. The link between prenatal exposures and latent health outcomes suggests that these exposures may result in long-term epigenetic reprogramming. Toxic metals and endocrine disruptors are two major classes of contaminants that are ubiquitously present in the environment and represent threats to human health. In this review, we present evidence that prenatal exposures to these contaminants result in fetal epigenomic changes, including altered global DNA methylation, gene-specific CpG methylation and microRNA expression. Importantly, these changes may have functional cellular consequences, impacting health outcomes later in life. Therefore, these epigenetic changes represent a critical mechanism that warrants further study.
Collapse
Affiliation(s)
- Paige A Bommarito
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Elizabeth Martin
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rebecca C Fry
- Department of Environmental Sciences & Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Curriculum in Toxicology, University of North Carolina School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27516, USA
| |
Collapse
|
16
|
Rojas D, Rager JE, Smeester L, Bailey KA, Drobná Z, Rubio-Andrade M, Stýblo M, García-Vargas G, Fry RC. Prenatal arsenic exposure and the epigenome: identifying sites of 5-methylcytosine alterations that predict functional changes in gene expression in newborn cord blood and subsequent birth outcomes. Toxicol Sci 2015; 143:97-106. [PMID: 25304211 PMCID: PMC4274382 DOI: 10.1093/toxsci/kfu210] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Prenatal exposure to inorganic arsenic (iAs) is detrimental to the health of newborns and increases the risk of disease development later in life. Here we examined a subset of newborn cord blood leukocyte samples collected from subjects enrolled in the Biomarkers of Exposure to ARsenic (BEAR) pregnancy cohort in Gómez Palacio, Mexico, who were exposed to a range of drinking water arsenic concentrations (0.456-236 µg/l). Changes in iAs-associated DNA 5-methylcytosine methylation were assessed across 424,935 CpG sites representing 18,761 genes and compared with corresponding mRNA expression levels and birth outcomes. In the context of arsenic exposure, a total of 2919 genes were identified with iAs-associated differences in DNA methylation. Site-specific analyses identified DNA methylation changes that were most predictive of gene expression levels where CpG methylation within CpG islands positioned within the first exon, the 5' untranslated region and 200 bp upstream of the transcription start site yielded the most significant association with gene expression levels. A set of 16 genes was identified with correlated iAs-associated changes in DNA methylation and mRNA expression and all were highly enriched for binding sites of the early growth response (EGR) and CCCTC-binding factor (CTCF) transcription factors. Furthermore, DNA methylation levels of 7 of these genes were associated with differences in birth outcomes including gestational age and head circumference.These data highlight the complex interplay between DNA methylation, functional changes in gene expression and health outcomes and underscore the need for functional analyses coupled to epigenetic assessments.
Collapse
Affiliation(s)
- Daniel Rojas
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Julia E Rager
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Lisa Smeester
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Kathryn A Bailey
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Zuzana Drobná
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Marisela Rubio-Andrade
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Miroslav Stýblo
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Gonzalo García-Vargas
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| | - Rebecca C Fry
- *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico *Curriculum in Toxicology, Department of Environmental Sciences and Engineering, Department of Nutrition and Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina and Facultad de Medicina, Universidad Juárez del Estado de Durango, Gómez Palacio, Durango, Mexico
| |
Collapse
|
17
|
Prenatal exposure to arsenic and cadmium impacts infectious disease-related genes within the glucocorticoid receptor signal transduction pathway. Int J Mol Sci 2014; 15:22374-91. [PMID: 25479081 PMCID: PMC4284714 DOI: 10.3390/ijms151222374] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 11/04/2014] [Accepted: 11/26/2014] [Indexed: 01/27/2023] Open
Abstract
There is increasing evidence that environmental agents mediate susceptibility to infectious disease. Studies support the impact of prenatal/early life exposure to the environmental metals inorganic arsenic (iAs) and cadmium (Cd) on increased risk for susceptibility to infection. The specific biological mechanisms that underlie such exposure-mediated effects remain understudied. This research aimed to identify key genes/signal transduction pathways that associate prenatal exposure to these toxic metals with changes in infectious disease susceptibility using a Comparative Genomic Enrichment Method (CGEM). Using CGEM an infectious disease gene (IDG) database was developed comprising 1085 genes with known roles in viral, bacterial, and parasitic disease pathways. Subsequently, datasets collected from human pregnancy cohorts exposed to iAs or Cd were examined in relationship to the IDGs, specifically focusing on data representing epigenetic modifications (5-methyl cytosine), genomic perturbations (mRNA expression), and proteomic shifts (protein expression). A set of 82 infection and exposure-related genes was identified and found to be enriched for their role in the glucocorticoid receptor signal transduction pathway. Given their common identification across numerous human cohorts and their known toxicological role in disease, the identified genes within the glucocorticoid signal transduction pathway may underlie altered infectious disease susceptibility associated with prenatal exposures to the toxic metals iAs and Cd in humans.
Collapse
|
18
|
Ray PD, Yosim A, Fry RC. Incorporating epigenetic data into the risk assessment process for the toxic metals arsenic, cadmium, chromium, lead, and mercury: strategies and challenges. Front Genet 2014; 5:201. [PMID: 25076963 PMCID: PMC4100550 DOI: 10.3389/fgene.2014.00201] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 06/16/2014] [Indexed: 12/24/2022] Open
Abstract
Exposure to toxic metals poses a serious human health hazard based on ubiquitous environmental presence, the extent of exposure, and the toxicity and disease states associated with exposure. This global health issue warrants accurate and reliable models derived from the risk assessment process to predict disease risk in populations. There has been considerable interest recently in the impact of environmental toxicants such as toxic metals on the epigenome. Epigenetic modifications are alterations to an individual's genome without a change in the DNA sequence, and include, but are not limited to, three commonly studied alterations: DNA methylation, histone modification, and non-coding RNA expression. Given the role of epigenetic alterations in regulating gene and thus protein expression, there is the potential for the integration of toxic metal-induced epigenetic alterations as informative factors in the risk assessment process. In the present review, epigenetic alterations induced by five high priority toxic metals/metalloids are prioritized for analysis and their possible inclusion into the risk assessment process is discussed.
Collapse
Affiliation(s)
- Paul D. Ray
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North CarolinaChapel Hill, NC, USA
- Curriculum in Toxicology, School of Medicine, University of North CarolinaChapel Hill, NC, USA
| | - Andrew Yosim
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North CarolinaChapel Hill, NC, USA
| | - Rebecca C. Fry
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North CarolinaChapel Hill, NC, USA
- Curriculum in Toxicology, School of Medicine, University of North CarolinaChapel Hill, NC, USA
| |
Collapse
|