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Li B, Jin X, Chan HM. Effects of low doses of methylmercury (MeHg) exposure on definitive endoderm cell differentiation in human embryonic stem cells. Arch Toxicol 2023; 97:2625-2641. [PMID: 37612375 PMCID: PMC10475006 DOI: 10.1007/s00204-023-03580-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/03/2023] [Indexed: 08/25/2023]
Abstract
Fetal development is one of the most sensitive windows to methylmercury (MeHg) toxicity. Laboratory and epidemiological studies have shown a dose-response relationship between fetal MeHg exposure and neuro performance in different life stages from infants to adults. In addition, MeHg exposure has been reported to be associated with disorders in endoderm-derived organs, such as morphological changes in liver cells and pancreatic cell dysfunctions. However, the mechanisms of the effects of MeHg on non-neuronal organs or systems, especially during the early development of endoderm-derived organs, remain unclear. Here we determined the effects of low concentrations of MeHg exposure during the differentiation of definitive endoderm (DE) cells from human embryonic stem cells (hESCs). hESCs were exposed to MeHg (0, 10, 100, and 200 nM) that covers the range of Hg concentrations typically found in human maternal blood during DE cell induction. Transcriptomic analysis showed that sub-lethal doses of MeHg exposure could alter global gene expression patterns during hESC to DE cell differentiation, leading to increased expression of endodermal genes/proteins and the over-promotion of endodermal fate, mainly through disrupting calcium homeostasis and generating ROS. Bioinformatic analysis results suggested that MeHg exerts its developmental toxicity mainly by disrupting ribosome biogenesis during early cell lineage differentiation. This disruption could lead to aberrant growth or dysfunctions of the developing endoderm-derived organs, and it may be the underlying mechanism for the observed congenital diseases later in life. Based on the results, we proposed an adverse outcome pathway for the effects of MeHg exposure during human embryonic stem cells to definitive endoderm differentiation.
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Affiliation(s)
- Bai Li
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada
| | - Xiaolei Jin
- Regulatory Toxicology Research Division, Bureau of Chemical Safety, Food Directorate, HPFB, Health Canada, 251 Sir Frederick Banting Driveway, Ottawa, ON, K1A 0K9, Canada.
| | - Hing Man Chan
- Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON, K1N 6N5, Canada.
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2
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Wells EM, Kopylev L, Nachman R, Radke EG, Congleton J, Segal D. Total Blood Mercury Predicts Methylmercury Exposure in Fish and Shellfish Consumers. Biol Trace Elem Res 2022; 200:3867-3875. [PMID: 34686996 PMCID: PMC9200869 DOI: 10.1007/s12011-021-02968-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 10/12/2021] [Indexed: 11/17/2022]
Abstract
Many studies evaluating methylmercury (MeHg) toxicity rely on whole blood total mercury (THg) measurements to estimate MeHg exposure. However, whole blood THg includes other forms of mercury (Hg), such as inorganic Hg, which have different exposure sources and toxicological effects than MeHg. Therefore, estimating the whole blood MeHg/THg ratio is critical to predicting MeHg exposure and, subsequently, efforts to establish an exposure-response relationship for use in risk assessment. A large, representative dataset (National Health and Nutrition Examination Survey (NHANES) 2011-2016) was used to determine the whole blood MeHg/THg ratio among (a) self-reported fish and shellfish consumers, ≥ 15 years of age (the "full adult" population (N = 5268 training dataset; N = 2336 test dataset)) and (b) female fish and shellfish consumers, 15-44 years of age (the "women of reproductive age" population (N = 1285 training dataset; N = 560 test dataset)). Unadjusted and adjusted linear and spline models with direct measurements for both THg and MeHg were evaluated. The mean whole blood MeHg/THg ratio was 0.75 (95% confidence interval (CI): 0.74, 0.75). This ratio was significantly higher among those with higher THg concentrations. All models exhibited excellent fit (adjusted R2 from 0.957 to 0.982). Performance was slightly improved in spline versus linear models. For the full adult population and women of reproductive age, the unadjusted spline model predicted whole blood MeHg concentrations of 5.65 µg/L and 5.55 µg/L, respectively, when the THg concentration was 5.80 µg/L. These results suggest that whole blood THg is a good predictor of whole blood MeHg among fish and shellfish consumers.
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Affiliation(s)
- Ellen M. Wells
- School of Health Sciences, Purdue University, West Lafayette, IN USA
- Department of Public Health, Purdue University, West Lafayette, IN USA
| | - Leonid Kopylev
- Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 1200 Pennsylvania Ave, Washington DC, NW 20460 USA
| | - Rebecca Nachman
- Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 1200 Pennsylvania Ave, Washington DC, NW 20460 USA
| | - Elizabeth G. Radke
- Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 1200 Pennsylvania Ave, Washington DC, NW 20460 USA
| | - Johanna Congleton
- Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 1200 Pennsylvania Ave, Washington DC, NW 20460 USA
| | - Deborah Segal
- Center for Public Health and Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, 1200 Pennsylvania Ave, Washington DC, NW 20460 USA
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3
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Transport and Toxicity of Methylmercury-Cysteine in Cultured BeWo Cells. Int J Mol Sci 2021; 23:ijms23010394. [PMID: 35008820 PMCID: PMC8745507 DOI: 10.3390/ijms23010394] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/24/2021] [Accepted: 12/27/2021] [Indexed: 11/16/2022] Open
Abstract
Mercury is a heavy metal toxicant that is prevalent throughout the environment. Organic forms of mercury, such as methylmercury (MeHg), can cross the placenta and can lead to lasting detrimental effects in the fetus. The toxicological effects of MeHg on the placenta itself have not been clearly defined. Therefore, the purpose of the current study was to assess the transport of MeHg into placental syncytiotrophoblasts and to characterize the mechanisms by which MeHg exerts its toxic effects. Cultured placental syncytiotrophoblasts (BeWo) were used for these studies. The transport of radioactive MeHg was measured to identify potential mechanisms involved in the uptake of this compound. The toxicological effects of MeHg on BeWo cells were determined by assessing visible pathological change, autophagy, mitochondrial viability, and oxidative stress. The findings of this study suggest that MeHg compounds are transported into BeWo cells primarily by sodium-independent amino acid carriers and organic anion transporters. The MeHg altered mitochondrial function and viability, decreased mitophagy and autophagy, and increased oxidative stress. Exposure to higher concentrations of MeHg inhibited the ability of cells to protect against MeHg-induced injury. The findings show that MeHg is directly toxic to syncytiotrophoblasts and may lead to disruptions in the fetal/maternal transfer of nutrients and wastes.
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Dufault RJ, Wolle MM, Kingston HMS, Gilbert SG, Murray JA. Connecting inorganic mercury and lead measurements in blood to dietary sources of exposure that may impact child development. World J Methodol 2021; 11:144-159. [PMID: 34322366 PMCID: PMC8299913 DOI: 10.5662/wjm.v11.i4.144] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/27/2021] [Accepted: 06/16/2021] [Indexed: 02/06/2023] Open
Abstract
Pre-natal and post-natal chemical exposures and co-exposures from a variety of sources including contaminated air, water, soil, and food are common and associated with poorer birth and child health outcomes. Poor diet is a contributing factor in the development of child behavioral disorders. Child behavior and learning can be adversely impacted when gene expression is altered by dietary transcription factors such as zinc insufficiency or deficiency or by exposure to toxic substances permitted in our food supply such as mercury, lead, or organophosphate pesticide residue. Children with autism spectrum disorder and attention deficit hyperactivity disorders exhibit decreased or impaired PON1 gene activity which is needed by the body to metabolize and excrete neurotoxic organophosphate pesticides. In this current review we present an updated macroepigenetic model that explains how dietary inorganic mercury and lead exposures from unhealthy diet may lead to elevated blood mercury and/or lead levels and the development of symptoms associated with the autism and attention deficit-hyperactivity disorders. PON1 gene activity may be suppressed by inadequate dietary calcium, selenium, and fatty acid intake or exposures to lead or mercury. The model may assist clinicians in diagnosing and treating the symptoms associated with these childhood neurodevelopmental disorders. Recommendations for future research are provided based on the updated model and review of recently published literature.
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Affiliation(s)
- Renee J Dufault
- Food Ingredient and Health Research Institute, Naalehu, HI 96772, United States
- College of Graduate Health Studies, A.T. Still University, Kirksville, MO 63501, United States
| | - Mesay M Wolle
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282, United States
| | - H M Skip Kingston
- Food Ingredient and Health Research Institute, Naalehu, HI 96772, United States
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282, United States
| | - Steven G Gilbert
- Food Ingredient and Health Research Institute, Naalehu, HI 96772, United States
- Institute of Neurotoxicology and Neurological Disorders, Seattle, WA 98105, United States
| | - Joseph A Murray
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN 55905, United States
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5
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't Mannetje A, Coakley J, Douwes J. Total blood mercury and its determinants in New Zealand children and adults. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2021; 31:289-298. [PMID: 33603094 DOI: 10.1038/s41370-021-00296-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Mercury is a widespread persistent environmental pollutant associated with adverse health effects. OBJECTIVE This first national biomonitoring survey of blood total mercury (tHg) conducted in New Zealand aimed to provide baseline data and identify exposure determinants. METHODS Blood was collected from 191 children (age 5-18 years) and 304 adults (20-65) in 2014-2016 and analysed for tHg using inductively coupled plasma mass spectrometry. Linear regression was used to assess associations with demographic and lifestyle factors. RESULTS Blood mercury was detected in 93% of children and 99% of adults, with geometric means (GMs) of 0.86 and 1.65 µg/L, respectively. The 60-65-year olds had the highest GM (2.34 µg/L). Regression indicated that tHg was 40% higher in boys compared to girls. Eating fish ≥ 3 times/week (compared to ≤once/week) was associated with 2.7 and 1.7 times higher tHg in children and adults, respectively. Shellfish consumption was also associated with higher tHg. High daily tap water consumption (≥2 L for children, ≥3 L for adults) was associated with lower tHg. In adults, smoking and milk consumption were associated with higher tHg. SIGNIFICANCE Fish and shellfish consumption is a strong determinant of New Zealanders blood tHg levels, with water and milk consumption possibly acting as modulating factors.
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Affiliation(s)
- Andrea 't Mannetje
- Centre for Public Health Research, Massey University, Wellington, New Zealand.
| | - Jonathan Coakley
- Centre for Public Health Research, Massey University, Wellington, New Zealand
| | - Jeroen Douwes
- Centre for Public Health Research, Massey University, Wellington, New Zealand
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Wickliffe JK, Lichtveld MY, Zijlmans CW, MacDonald-Ottevanger S, Shafer M, Dahman C, Harville EW, Drury S, Landburg G, Ouboter P. Exposure to total and methylmercury among pregnant women in Suriname: sources and public health implications. JOURNAL OF EXPOSURE SCIENCE & ENVIRONMENTAL EPIDEMIOLOGY 2021; 31:117-125. [PMID: 32461550 PMCID: PMC7704553 DOI: 10.1038/s41370-020-0233-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 04/17/2020] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
Previous research has found that women and children living in rural, interior communities in Suriname have high concentrations of mercury in hair. Freshwater fish from these areas also have high concentrations of mercury. Artisanal and small-scale gold mining operations in parts of the country use elemental mercury to extract gold from soils and sediments. Total mercury and methylmercury concentrations have been determined in hair and blood from pregnant women across the country. Pregnant women from interior communities have significantly higher concentrations of both total and methylmercury in hair (median total mercury in hair 3.64 µg/g) compared with pregnant women from two urban coastal cities, Paramaribo (0.63 µg/g) and Nickerie (0.74 µg/g). Total and methylmercury concentrations in blood and hair are highly correlated (r = 0.986, r = 0.974) with methylmercury making up 86% of the total in blood and 97% of the total in hair. Most women in the interior regions rely heavily on local fish as part of their regular diet, and many live outsides of areas with active ASGM operations. This study demonstrates that diet and fish consumption largely govern mercury exposures in pregnant women in Suriname.
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Affiliation(s)
- Jeffrey K Wickliffe
- Department of Global Environmental Health Sciences, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, 70112, USA.
| | - Maureen Y Lichtveld
- Department of Global Environmental Health Sciences, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, 70112, USA
| | - C Wilco Zijlmans
- Academic Hospital Paramaribo, Scientific Research Center Suriname, Paramaribo, Suriname
- Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname
| | | | - Martin Shafer
- Wisconsin State Laboratory of Hygiene, University of Wisconsin-Madison, Madison, WI, 53718, USA
| | - Christa Dahman
- Wisconsin State Laboratory of Hygiene, University of Wisconsin-Madison, Madison, WI, 53718, USA
| | - Emily W Harville
- Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, 70112, USA
| | - Stacy Drury
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Tulane University, New Orleans, LA, 70112, USA
| | - Gwendolyn Landburg
- National Zoological Collection of Suriname/Environmental Research Center (NZCS/CMO), Anton de Kom University of Suriname, Paramaribo, Suriname
| | - Paul Ouboter
- National Zoological Collection of Suriname/Environmental Research Center (NZCS/CMO), Anton de Kom University of Suriname, Paramaribo, Suriname
- Institute for Neotropical Wildlife and Environmental Studies (NeoWild), Paramaribo, Suriname
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7
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Chemical analysis of Hg0-containing Hindu religious objects. PLoS One 2019; 14:e0226855. [PMID: 31887195 PMCID: PMC6936866 DOI: 10.1371/journal.pone.0226855] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/05/2019] [Indexed: 12/02/2022] Open
Abstract
Parad items used in Hindu practices and Ayurvedic medicines contain elemental mercury (Hg0) and have traditionally been used in prayer and to treat a variety of diseases including diabetes, heart conditions, and sexual dysfunction. These items are often referred to as amalgams of silver, and take the form of shivlings, statues of gods, necklaces, and other jewelry. Fourteen parad items were purchased from online vendors in India and the United States and analyzed. All items produced copious amounts of Hg0 vapor, with Hg0 concentrations exceeding 1,000,000 ng/m3 as measured using a Mercury Instruments Mercury Tracker 3000 IP atomic absorption spectrometer. Measured concentrations were highly variable, so a simple qualitative experiment employing a UV-C light source and a thin-layer chromatography plate impregnated with a fluorescent dye that glows green when irradiated at 254 nm allowed for the indirect visualization of the Hg0 being evolved. In addition, all items were screened using a hand-held X-ray fluorescence analyzer to estimate the concentration of Hg, Sn, Pb, As, and Cd on the surface of the item. Select samples were then digested in aqua regia and analyzed for Hg content using a direct mercury analyzer. All samples were found to exceed 20% by mass Hg. The digestates were analyzed using inductively-coupled plasma–optical emission spectrometry and were determined to be between 10–55% by mass Pb and contain up to 0.3% by mass As. While Article 4 of the Minamata Convention on Mercury specifically requires parties to stop importing, exporting, and manufacturing Hg-added products, products used in traditional and religious practices are excluded.
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8
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Rand MD, Caito SW. Variation in the biological half-life of methylmercury in humans: Methods, measurements and meaning. Biochim Biophys Acta Gen Subj 2019; 1863:129301. [PMID: 30742954 DOI: 10.1016/j.bbagen.2019.02.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 01/04/2019] [Accepted: 02/01/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND Understanding methylmercury (MeHg) toxicity requires a complete understanding of its fundamental toxicokinetic and toxicodynamic characteristics in the human body. The biological half-life (t1/2) of MeHg is a kinetic property that directly influences the body burden of Hg that results from repeated exposures such as can occur with fish and seafood consumption. The t1/2 of MeHg in humans is approximately 50 days, equivalent to an elimination rate (kel) of 0.014 day-1. However, numerous studies report a wide range of half-life values (t1/2 < 30 to >120 days), demonstrating that significant variation in the biological process of MeHg elimination exists. This variation is a source of considerable uncertainty in deriving a meaningful reference dose for MeHg applicable to all individuals in a population. SCOPE OF REVIEW First, we summarize fundamentals of MeHg toxicokinetics, emphasizing the central role that biological half-life plays in MeHg dosimetry. We next present important considerations for how kinetic analyses are performed. We provide an example of how MeHg half-life variation directly influences the body burden and, in certain contexts, can result in MeHg levels exceeding the US EPA Reference Dose. We then survey existing studies that report MeHg half-life determinations in people. MAJOR CONCLUSIONS Recent advances in methods of determining MeHg kinetics in people have made individualized assessment of MeHg elimination rates more accurate and readily obtainable. GENERAL SIGNIFICANCE Characterization of MeHg half-life, particularly in vulnerable individuals, such as pregnant women and children, will diminish the remaining toxicokinetic uncertainty surrounding MeHg exposures and will better inform the risk assessment process.
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Affiliation(s)
- Matthew D Rand
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States.
| | - Samuel W Caito
- Husson University, School of Pharmacy, Bangor, ME 04401, United States
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Leaf ethanolic extract of Etlingera hemesphaerica Blume alters mercuric chloride teratogenicity during the post-implantation period in Mus musculus. Toxicol Res 2019; 36:131-138. [PMID: 32257925 DOI: 10.1007/s43188-019-00010-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 06/01/2019] [Accepted: 06/25/2019] [Indexed: 02/06/2023] Open
Abstract
This study aimed to investigate the effectiveness of leaf ethanolic extract of Etlingera hemisphaerica (LE3H) against the teratogenic effects of mercuric chloride (HgCl2) in mice (Mus musculus). Pregnant M. musculus were divided into four groups, each consisting of 10 dams, and received drink and food ad libitum. The first, second, and third, and fourth (control) groups were administered with LE3H, HgCl2, HgCl2 + LE3H, and double-distilled water alone, respectively. HgCl2 (5 mg/kg bw) was administered by injection on gestation day (GD) 9, and LE3H (0.39 mg/g bw) was administered by gavage on GD 10. Treated and control animals were killed by cervical dislocation on GD 18, dissected, and the fetuses were collected for evaluation of maternal, embryonic, and fetal toxicity. Eight parameters were measured: (a) embryo resorption or resorbed embryo, (b) dead fetus, (c) living fetus, (d) morphologically normal living fetus, (e) malformed living fetus, (f) number of MLF, (g) length of MNLF, and (h) weight of MNLF. LE3H caused 4 (50.00%), whereas HgCl2 resulted in 7 (87.50%) parameters that were significantly different from those of the control, indicating that the teratogenicity of HgCl2 was significantly higher than that of LE3H. HgCl2 + LE3H showed two effects of LE3H on the teratogenicity of HgCl2: increased 2 (25.00%), and decreased 6 (75.00%). Thus, LE3H decreased the teratogenic effects of HgCl2 in M. musculus.
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Trdin A, Snoj Tratnik J, Mazej D, Fajon V, Krsnik M, Osredkar J, Prpić I, Špirić Z, Petrović O, Marc J, Neubauer D, Kodrič J, Kobal AB, Barbone F, Falnoga I, Horvat M. Mercury speciation in prenatal exposure in Slovenian and Croatian population - PHIME study. ENVIRONMENTAL RESEARCH 2019; 177:108627. [PMID: 31421448 DOI: 10.1016/j.envres.2019.108627] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 07/30/2019] [Accepted: 08/04/2019] [Indexed: 06/10/2023]
Abstract
In recent years, several studies have addressed the issue of prenatal exposure to methylmercury (MeHg); however, few have actually analysed MeHg blood concentrations. Our study population included mothers and their new-borns from Slovenia (central region; N = 584) and Croatia (coastal region; N = 234). We have measurements of total Hg (THg) and MeHg in maternal hair, maternal peripheral blood, and cord blood. Cord blood Hg concentrations were low to moderate (median THg = 1.84 ng/g and MeHg = 1.69 ng/g). The proportion of THg as MeHg (%MeHg) in maternal and cord blood varied between 4% and 100% (coefficient of variation, CV = 32%) and between 8% and 100% (CV = 20%), respectively. Our data shows that variability of %MeHg was higher at lower blood THg levels. Concentrations of MeHg in maternal blood and cord blood were highly correlated (Rs = 0.943), in the case of inorganic Hg correlation was significant but weaker (Rs = 0.198). MeHg levels in maternal blood and cord blood were positively associated with seafood intake, maternal age, and negatively associated with pre-pregnancy BMI. Additionally, MeHg in maternal blood was positively associated with plasma selenium levels, and cord blood MeHg was negatively associated with parity. The results of multiple linear regression models showed that speciation analysis provides more defined estimation of prenatal exposure in association modelling. Associations between Hg exposure and cognitive performance of children (assessed using Bayley Scales of Infant and Toddler development) adjusted for maternal or child Apolipoprotein E genotypes showed higher model R2 and lower p-values when adjusted for MeHg compared to THg. This study demonstrates that Hg speciation improves the association between exposure and possible negative health effects.
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Affiliation(s)
- Ajda Trdin
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Janja Snoj Tratnik
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Darja Mazej
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Vesna Fajon
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Ljubljana, Slovenia
| | - Mladen Krsnik
- Institute of Clinical Chemistry and Biochemistry, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Joško Osredkar
- Institute of Clinical Chemistry and Biochemistry, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Igor Prpić
- Department of Paediatrics, University Hospital Centre Rijeka, Rijeka, Croatia
| | | | - Oleg Petrović
- Department of Obstetrics and Gynaecology, University Hospital Centre Rijeka, Rijeka, Croatia
| | - Janja Marc
- Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
| | - David Neubauer
- Department of Child, Adolescent, and Developmental Neurology, Division of Paediatrics, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Jana Kodrič
- Department of Child, Adolescent, and Developmental Neurology, Division of Paediatrics, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Alfred B Kobal
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Fabio Barbone
- Institute for Maternal and Child Health - IRCCS "Burlo Garofolo", Trieste, Italy
| | - Ingrid Falnoga
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Milena Horvat
- Department of Environmental Sciences, Jožef Stefan Institute, Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Ljubljana, Slovenia.
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Caspersen IH, Thomsen C, Haug LS, Knutsen HK, Brantsæter AL, Papadopoulou E, Erlund I, Lundh T, Alexander J, Meltzer HM. Patterns and dietary determinants of essential and toxic elements in blood measured in mid-pregnancy: The Norwegian Environmental Biobank. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 671:299-308. [PMID: 30928759 DOI: 10.1016/j.scitotenv.2019.03.291] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/13/2019] [Accepted: 03/19/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Inadequate stores or intakes of essential minerals in pregnancy, or too high exposure to both toxic and essential elements, can have adverse effects on mother and child. The main aims of this study were to 1) describe the concentrations and patterns of essential and toxic elements measured in maternal whole blood during pregnancy; 2) identify dietary, lifestyle and sociodemographic determinants of element status; and 3) explore the impact of iron deficiency on blood element concentrations. METHODS This study is based on blood samples collected from 2982 women in gestational week 18 in The Norwegian Mother and Child Cohort study (MoBa) which were analyzed as part of the Norwegian Environmental Biobank. We derived blood element patterns by exploratory factor analysis, and associations between blood element patterns and diet were explored using sparse partial least squares (sPLS) regression. RESULTS Blood concentrations were determined for the essential elements (in the order of most abundant) Zn > Cu > Se > Mn > Mo > Co, and the toxic metals Pb > As > Hg > Cd > Tl. The concentrations were in ranges that were similar to or sometimes more favorable than in other pregnant and non-pregnant European women. We identified two blood element patterns; one including Zn, Se and Mn and another including Hg and As. For the Zn-Se-Mn pattern, use of multimineral supplements was the most important dietary determinant, while a high score in the Hg-As pattern was mainly determined by seafood consumption. Concentrations of Mn, Cd and Co were significantly higher in women with iron deficiency (plasma ferritin < 12 μg/L) than in women with plasma ferritin ≥ 12 μg/L. CONCLUSION Our study illustrates complex relationships and coexistence of essential and toxic elements. Their potential interplay adds to the challenges of studies investigating health effects related to either diet or toxicants.
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Affiliation(s)
- Ida Henriette Caspersen
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
| | - Cathrine Thomsen
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Line Småstuen Haug
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Helle K Knutsen
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Anne Lise Brantsæter
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Eleni Papadopoulou
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Iris Erlund
- Genomics and Biomarkers Unit, National Institute for Health and Welfare, Helsinki, Finland
| | - Thomas Lundh
- Division of Occupational and Environmental Medicine, Institution of Laboratory Medicine, Lund University, Lund, Sweden
| | - Jan Alexander
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Helle Margrete Meltzer
- Division of Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
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Raciti M, Salma J, Spulber S, Gaudenzi G, Khalajzeyqami Z, Conti M, Anderlid BM, Falk A, Hermanson O, Ceccatelli S. NRXN1 Deletion and Exposure to Methylmercury Increase Astrocyte Differentiation by Different Notch-Dependent Transcriptional Mechanisms. Front Genet 2019; 10:593. [PMID: 31316548 PMCID: PMC6610538 DOI: 10.3389/fgene.2019.00593] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 06/05/2019] [Indexed: 01/11/2023] Open
Abstract
Controversial evidence points to a possible involvement of methylmercury (MeHg) in the etiopathogenesis of autism spectrum disorders (ASD). In the present study, we used human neuroepithelial stem cells from healthy donors and from an autistic patient bearing a bi-allelic deletion in the gene encoding for NRXN1 to evaluate whether MeHg would induce cellular changes comparable to those seen in cells derived from the ASD patient. In healthy cells, a subcytotoxic concentration of MeHg enhanced astroglial differentiation similarly to what observed in the diseased cells (N1), as shown by the number of GFAP positive cells and immunofluorescence signal intensity. In both healthy MeHg-treated and N1 untreated cells, aberrations in Notch pathway activity seemed to play a critical role in promoting the differentiation toward glia. Accordingly, treatment with the established Notch inhibitor DAPT reversed the altered differentiation. Although our data are not conclusive since only one of the genes involved in ASD is considered, the results provide novel evidence suggesting that developmental exposure to MeHg, even at subcytotoxic concentrations, induces alterations in astroglial differentiation similar to those observed in ASD.
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Affiliation(s)
- Marilena Raciti
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jahan Salma
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Stefan Spulber
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Giulia Gaudenzi
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Mirko Conti
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Britt-Marie Anderlid
- Centre for Molecular Medicine, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Anna Falk
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ola Hermanson
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Sandra Ceccatelli
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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Rothenberg SE, Wagner CL, Hamidi B, Alekseyenko AV, Andrea Azcarate-Peril M. Longitudinal changes during pregnancy in gut microbiota and methylmercury biomarkers, and reversal of microbe-exposure correlations. ENVIRONMENTAL RESEARCH 2019; 172:700-712. [PMID: 30903970 PMCID: PMC6675619 DOI: 10.1016/j.envres.2019.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 01/06/2019] [Accepted: 01/08/2019] [Indexed: 06/09/2023]
Abstract
OBJECTIVE Gut microorganisms contribute to the metabolism of environmental toxicants, including methylmercury (MeHg). Our main objective was to investigate whether associations between biomarkers for prenatal MeHg exposure and maternal gut microbiota differed between early and late gestation. METHODS Maternal blood and stool samples were collected during early (8.3-17 weeks, n=28) and late (27-36 weeks, n=24) gestation. Total mercury and MeHg concentrations were quantified in biomarkers, and inorganic mercury was estimated by subtraction. The diversity and structure of the gut microbiota were investigated using 16S rRNA gene profiling (n = 52). Biomarkers were dichotomized, and diversity patterns were compared between high/low mercury concentrations. Spearman's correlation was used to assess bivariate associations between MeHg biomarkers (stool, blood, and meconium), and 23 gut microbial taxa (genus or family level, >1% average relative abundance). RESULTS Within-person and between-person diversity patterns in gut microbiota differed between early/late gestation. The overall composition of the microbiome differed between high/low MeHg concentrations (in blood and stool) during early gestation, but not late gestation. Ten (of 23) taxa were significantly correlated with MeHg biomarkers (increasing or decreasing); however, associations differed, depending on whether the sample was collected during early or late gestation. A total of 43% of associations (69/161) reversed the direction of correlation between early/late gestation. CONCLUSIONS The time point at which a maternal fecal sample is collected may yield different associations between gut microorganisms and MeHg biomarkers, which may be due in part to remodeling of maternal microbiota during pregnancy. Our results suggest the effectiveness of dietary interventions to reduce prenatal MeHg exposure may differ between early and late gestation.
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Affiliation(s)
- Sarah E Rothenberg
- School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon, USA.
| | - Carol L Wagner
- Department of Pediatrics, Medical University of South Carolina, Charleston, SC, USA
| | - Bashir Hamidi
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Alexander V Alekseyenko
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - M Andrea Azcarate-Peril
- Division of Gastroenterology and Hepatology and Microbiome Core Facility, University of North Carolina, Chapel Hill, NC, USA
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