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Ma B, Zhao X, Zhang X, Yang B, Cai Z, Xing Z, Xu M, Mi L, Zhang J, Wang L, Zhao Y, Liu X. The acute neurotoxicity of inorganic mercury in Mactra chinensis philippi. Aquat Toxicol 2024; 270:106896. [PMID: 38490093 DOI: 10.1016/j.aquatox.2024.106896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 02/05/2024] [Accepted: 03/11/2024] [Indexed: 03/17/2024]
Abstract
Inorganic mercury (IHg) is hazardous to marine organisms especially resulting in neurotoxicity, bivalves are sensitive to pollutants as "ocean sentinel", but data on the neurotoxicity of IHg in bivalves are sparse. So we chosed M. chinensis philippi with typical neural structures in bivalves to investigate the neurotoxicity of IHg, which could be helpful to understand the specificity of neural regulation and the response characteristics of bivalves. After acute exposed to IHg (HgCl2) for 24 h, the metabolites of ganglion tissues in M. chinensis philippi were evaluated using 1H-nuclear magnetic resonance based metabolomics; Ca2+, neurotransmitters (nitric oxide, glutamate, acetylcholine) and related enzymes (calcineurin, nitric oxide synthase and acetylcholinesterase) were measured using biochemical detection. Compared to the control group, the levels of the nitric oxide (81.04 ± 12.84 μmol/g prot) and acetylcholine (30.93 ± 12.57 μg/mg prot) in M. chinensis philippi of IHg-treated were decreased, while glutamate (2.11 ± 0.61 mmol/L) increased significantly; the activity of nitric oxide synthase (679.34 ± 135.33 U/mg prot) was increased, while acetylcholinesterase (1.39 ± 0.44 U/mg prot) decreased significantly, and the activity of calcineurin (0.52 ± 0.02 U/mg prot) had a statistically insignificant increasing tendency. The concentration of Ca2+ (0.92 ± 0.46 mmol/g prot) in the IHg-treated group was significantly higher than that in the control group. OPLS-DA was performed to reveal the difference in metabolites between the control and IHg-challenged groups, the metabolites of glucose, glutamine, inosine, succinate, glutamate, homarine, and alanine were sensitive to IHg, subsequently metabolic pathways that were affected including glucose metabolism, glutamine metabolism, nucleotide metabolism, Krebs cycle, amino acid metabolism and osmotic regulation. In our study, IHg interfered with metabolites in M. chinensis philippi, thus the corresponding metabolic pathways were changed, which influenced the neurotransmitters subsequently. Furthermore, Ca2+overload affected the synthesis or degradation of the neurotransmitters, and then the altered neurotransmitters involved in changes in metabolic pathways again. Overall, we hypothesized that the neurotoxic effects of IHg on bivalve were in close contact with metabolism, neurotransmitters, related enzymes and Ca2+, which could be effective neurotoxic biomarkers for marine environmental quality assessment, and also provide effective data for the study of the regulatory mechanism of the nervous system in response to IHg in bivalves.
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Affiliation(s)
- Bangguo Ma
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | - Xiaoli Zhao
- Center for Reproductive Medicine, Yantai Yuhuangding Hospital, Yantai 264000, PR China
| | - Xiaoning Zhang
- The Key Laboratory of Mariculture, Ministry of Education, Fisheries College, Ocean University of China, Qingdao 266003, PR China
| | - Bowen Yang
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Zimin Cai
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | - Zihan Xing
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | - Mingzhe Xu
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | - Liuya Mi
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | | | - Lei Wang
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | - Yancui Zhao
- School of Life Sciences, Ludong University, Yantai 264025, PR China
| | - Xiaoli Liu
- School of Life Sciences, Ludong University, Yantai 264025, PR China.
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Santos JP, Li W, Keller AA, Slaveykova VI. Mercury species induce metabolic reprogramming in freshwater diatom Cyclotella meneghiniana. J Hazard Mater 2024; 465:133245. [PMID: 38150761 DOI: 10.1016/j.jhazmat.2023.133245] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 12/06/2023] [Accepted: 12/10/2023] [Indexed: 12/29/2023]
Abstract
Mercury is a hazardous pollutant of global concern. While advances have been made in identifying the detrimental effects caused by Hg species in phytoplankton, knowledge gaps remain regarding the metabolomic perturbations induced by inorganic mercury (Hg(II)) and monomethylmercury (MeHg) in these organisms. Diatoms represent a major phytoplankton group essential in various global biogeochemical cycles. The current study combined targeted metabolomics, bioaccumulation, and physiological response assays to investigate metabolic perturbations in diatom Cyclotella meneghiniana exposed for 2 h to nanomolar concentrations of Hg(II) and MeHg. Our findings highlight that such exposures induce reprogramming of the metabolism of amino acids, nucleotides, fatty acids, carboxylic acids and antioxidants. These alterations were primarily mercury-species dependent. MeHg exposure induced more pronounced reprogramming of the metabolism of diatoms than Hg(II), which led to less pronounced effects on ROS generation, membrane permeability and chlorophyll concentrations. Hg(II) treatments presented distinct physiological responses, with more robust metabolic perturbations at higher exposures. The present study provides first-time insights into the main metabolic alterations in diatom C. meneghiniana during short-term exposure to Hg species, deepening our understanding of the molecular basis of these perturbations.
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Affiliation(s)
- João P Santos
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Environmental Biogeochemistry and Ecotoxicology, 66 Blvd Carl-Vogt, CH 1211 Geneva, Switzerland.
| | - Weiwei Li
- Bren School of Environmental Science & Management, University of California, Santa Barbara, CA 93106-5131, United States
| | - Arturo A Keller
- Bren School of Environmental Science & Management, University of California, Santa Barbara, CA 93106-5131, United States
| | - Vera I Slaveykova
- University of Geneva, Faculty of Sciences, Earth and Environment Sciences, Department F.-A. Forel for Environmental and Aquatic Sciences, Environmental Biogeochemistry and Ecotoxicology, 66 Blvd Carl-Vogt, CH 1211 Geneva, Switzerland.
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Rodríguez-Viso P, Domene A, Vélez D, Devesa V, Zúñiga M, Monedero V. Lactic acid bacteria strains reduce in vitro mercury toxicity on the intestinal mucosa. Food Chem Toxicol 2023; 173:113631. [PMID: 36690269 DOI: 10.1016/j.fct.2023.113631] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/13/2023] [Accepted: 01/19/2023] [Indexed: 01/22/2023]
Abstract
A bicameral model consisting of Caco-2 and HT29-MTX intestinal epithelial cells and THP-1-derived macrophages has been used to test the ability of two strains of Lactobacillus to protect from damage caused by mercury. Exposure to 1 mg/ml mercury [Hg(II) or methyl-Hg] for seven days in this model resulted in an inflammatory and pro-oxidant response mainly driven by macrophages. This led to an impairment in the intestinal barrier, defective tight-junctions, increased permeability and mucus hypersecretion. In addition, the wound-healing capacity of the epithelial monolayer was also diminished. However, the presence of heat-killed Lactobacillus intestinalis or Lactobacillus johnsonii cells during Hg exposure reverted these effects, and most of the parameters recovered values similar to control cells. Both lactobacilli showed the capacity to bind Hg(II) and methyl-Hg under the cell culture conditions. This points to Hg sequestration as a likely mechanism that counteracted Hg toxicity. However, differences in the Hg binding capacity and in the effects between both strains suggest that other probiotic-mediated mechanisms may play a role in the alleviation of the damage elicited by Hg. These results show the potential of the bicameral intestinal epithelial model for screening of effective strains for their use in later in vivo studies.
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Affiliation(s)
- Pilar Rodríguez-Viso
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Agustín Escardino 7, 46980, Paterna, Valencia, Spain.
| | - Adrián Domene
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Agustín Escardino 7, 46980, Paterna, Valencia, Spain.
| | - Dinoraz Vélez
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Agustín Escardino 7, 46980, Paterna, Valencia, Spain.
| | - Vicenta Devesa
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Agustín Escardino 7, 46980, Paterna, Valencia, Spain.
| | - Manuel Zúñiga
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Agustín Escardino 7, 46980, Paterna, Valencia, Spain.
| | - Vicente Monedero
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Agustín Escardino 7, 46980, Paterna, Valencia, Spain.
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Tian X, Lin X, Zhao J, Cui L, Gao Y, Yu YL, Li B, Li YF. Gut as the target tissue of mercury and the extraintestinal effects. Toxicology 2023; 484:153396. [PMID: 36521575 DOI: 10.1016/j.tox.2022.153396] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/09/2022] [Accepted: 12/09/2022] [Indexed: 12/15/2022]
Abstract
Mercury (Hg) is harmful to the environment and human health. The gut plays important roles as the biological, chemical, mechanical, and immune barriers in animals and human beings. It has been known that Hg can be absorbed and methylated/demethylated in the gut, on the other hand, the impacts of Hg to the gut (especially the gut microbiota) is less studied. This review paper summarizes the impacts of inorganic Hg (IHg) and methyl Hg (MeHg) on gut barriers and the extraintestinal effects (damage to other organs such as the liver and brain). Both IHg and MeHg were found to cause intestinal microbial disorders, abnormal metabolites production, tight junction damage, and immune responses in the gut. The damage to the gut also contributed to the extraintestinal effects like the hepatotoxicity by IHg and the neurotoxicity by MeHg. In all, it is proposed that the gut should be considered as an important target tissue of Hg exposure, and the regulation of gut microbiota may have the potential for the prevention and control of the toxicity of Hg.
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Marumoto M, Sakamoto M, Nakamura M, Marumoto K, Tsuruta S. Organ-specific accumulation of selenium and mercury in Indo-Pacific bottlenose dolphins (Tursiops aduncus). Acta Vet Scand 2022; 64:1. [PMID: 35086557 PMCID: PMC8796142 DOI: 10.1186/s13028-021-00607-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Accepted: 10/04/2021] [Indexed: 11/10/2022] Open
Abstract
Delphinids are top ocean predators and accumulate high concentrations of mercury (Hg) through the food chain, particularly in organs such as liver and kidney, although the proportion of methylmercury (MeHg) is relatively low due to the demethylation process. Total mercury (T-Hg) levels in marine mammals have been shown to correlate with selenium (Se) concentrations, and ingested MeHg that is demethylated may be present in tissues as mercury selenide (HgSe). In this study, we determined T-Hg, MeHg and Se concentrations of three Indo-Pacific bottlenose dolphins (Tursiops aduncus), and we used the individual with the highest Hg concentration for electron probe microanalysis to assess the co-localization of Hg and Se in the tissues. By electron probe microanalysis, we found that Hg and Se were co-localized in large granules in hepatic Kupffer cells and in small granules in hepatocytes. The analysis suggested that MeHg was demethylated in hepatocytes and then phagocytosed by Kupffer cells. In the kidney, Hg and Se were co-localized in the glomerular capillary wall and in interstitial blood vessel walls. Hg and Se were also co-localized in the cytoplasm of large neurons and in glial cells in the cerebrum. Divalent Hg and HgSe cannot cross the blood-brain barrier, suggesting that MeHg is demethylated in the dolphin brain and that binding to Se suppresses Hg toxicity.
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Nunes PBDO, Ferreira MKM, Ribeiro Frazão D, Bittencourt LO, Chemelo VDS, Silva MCF, Pereira-Neto AL, Albuquerque ARL, Paz SPA, Angélica RS, Pessanha S, Lima RR. Effects of inorganic mercury exposure in the alveolar bone of rats: an approach of qualitative and morphological aspects. PeerJ 2022; 10:e12573. [PMID: 35127276 PMCID: PMC8800384 DOI: 10.7717/peerj.12573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 11/09/2021] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND In comparison to organic mercury (MeHg), the environmental inorganic mercury (IHg) can be found in some skin-lightening cosmestics were considered "harmless" for a long time. However, recent studies have shown that long-term exposure to low doses of IHg may affect biological systems. Therefore, this study investigated the effects of IHg long-term exposure to the alveolar bone of adult rats. METHODS Adult Wistar rats were distributed in control and HgCl2 exposed (0.375 mg/kg/day). After 45 days, the rats were euthanized and both blood and hemimandibles were collected. Total blood Hg levels were measured and both inorganic and organic components of the alveolar bone were determined through XRD and ATR-FTIR. The microstructure of the alveolar bone was assessed by using micro-CT and the morphometric analysis was performed by using stereomicroscopy. RESULTS Alterations in the physicochemical components of the alveolar bone of exposed animals were observed. The bone changes represented a tissue reaction at the microstructural level, such as bone volume increase. However, no significant dimensional changes (bone height) were observed. CONCLUSION Exposure to IHg at this dose can promote microstructural changes and alteration in the organic and inorganic components in the alveolar bone.
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Affiliation(s)
- Paula Beatriz de Oliveira Nunes
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
| | - Maria Karolina Martins Ferreira
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
| | - Deborah Ribeiro Frazão
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
| | - Leonardo Oliveira Bittencourt
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
| | - Victória dos Santos Chemelo
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
| | - Márcia Cristina Freitas Silva
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
| | | | | | | | | | - Sofia Pessanha
- Laboratory of Instrumentation, Biomedical Engineering and Radiation Physics, NOVA School of Sciences and Technology, Caparica, Portugal
| | - Rafael Rodrigues Lima
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, Pará, Brazil
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Aslam MW, Meng B, Abdelhafiz MA, Liu J, Feng X. Unravelling the interactive effect of soil and atmospheric mercury influencing mercury distribution and accumulation in the soil-rice system. Sci Total Environ 2022; 803:149967. [PMID: 34482140 DOI: 10.1016/j.scitotenv.2021.149967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 08/24/2021] [Accepted: 08/24/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) accumulation in rice is an emerging health concern worldwide. However, sources and interactions responsible for Hg species accumulation in different rice tissues are still uncertain. Four experimental plots were carefully designed at an artisanal Hg mining site and a control site to evaluate the effect of atmospheric and soil Hg contents on Hg accumulation in rice. We showed that inorganic Hg (IHg) contents in rice tissues grown either in contaminated or control site soil (non-contaminated soil) were higher at Hg artisanal mining site than those at the control site. Elevated total gaseous mercury (TGM) levels in ambient air were the predominant source of IHg to rice at the Hg mining area. Methylmercury (MeHg) concentrations in rice plant tissues increased in proportionality with MeHg contents in paddy soil. Our results suggest that both atmosphere and soil Hg sources have been impacted the IHg accumulation in rice. Above ground rice tissues, grains, leaves, and stalk accumulated IHg from both atmosphere and soil to varying degrees. Nonetheless, the study also provides the first direct evidence that atmospheric Hg accumulated by above-ground rice tissues could be translocated to below-ground tissues (roots). However, the extent to which atmosphere or soil Hg contributes to IHg in rice tissues may vary with each source's concentration gradient at the given site. No evidence of in planta Hg methylation was found during the current study. Hence, paddy fields are potential MeHg production sites, whereas paddy soil is a unique MeHg accumulation source in rice plants. This study expands and clarifies the contribution of various sources involved in Hg accumulation in the soil rice system. The findings here provide the basis for future research strategies to deal with the global issue of Hg contaminated rice.
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Affiliation(s)
- Muhammad Wajahat Aslam
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China.
| | - Mahmoud A Abdelhafiz
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; Geology Department, Faculty of Science, Al-Azhar University, Assiut 71524, Egypt
| | - Jiang Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xian 710061, PR China.
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Lv W, Zhan T, Abdelhafiz MA, Feng X, Meng B. Selenium-amended biochar mitigates inorganic mercury and methylmercury accumulation in rice (Oryza sativa L.). Environ Pollut 2021; 291:118259. [PMID: 34600068 DOI: 10.1016/j.envpol.2021.118259] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/22/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
Rice, as a dominant crop in China and Asia, can be a major route of methylmercury (MeHg) exposure for humans in inland China, especially in those living in mercury (Hg) polluted areas. Soil is the most prominent MeHg accumulation source for rice grains. The development of management practices to reduce MeHg in rice grains is crucial. This study explored the mitigation effect of biochar (BC) and sodium selenite-amended biochar (BC + Se) on MeHg production in paddy soil and accumulation in rice. Mercury-contaminated soil was treated with 1% and 5% of both BC and BC + Se. Soil MeHg concentration slightly increased under 1% BC/BC + Se compared to control soil but decreased at the rate of 5%. Moreover, soil phytoavailable MeHg (P-MeHg) diminished as the amount of Se-amended BC increased. BC + Se effectively mitigated MeHg accumulation in rice grains. The highest average contents of MeHg and inorganic Hg (IHg) in rice seeds were found in the control samples, followed by the 1%-BC, 5%-BC, 1%-BC + Se, and 5%-BC + Se samples. Under the 5%-BC + Se treatment, rice MeHg levels were reduced significantly (94%) compared to the control, and P-MeHg concentrations in soil were lower than all the other experimental groups throughout the rice-growing season. These results demonstrate the effectiveness of BC + Se in reducing MeHg and IHg accumulation in rice and could be employed for remediation of Hg polluted paddies.
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Affiliation(s)
- Wenqiang Lv
- School of Geography and Resources, Guizhou Education University, Guiyang, Guizhou, 550018, China
| | - Tianli Zhan
- Institute of Mountain Resources of Guizhou Province, Guiyang, 550001, China
| | - Mahmoud A Abdelhafiz
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Geology Department, Faculty of Science, Al-Azhar University, Assiut, 71524, Egypt
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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Lin X, Zhang W, He L, Xie H, Feng B, Zhu H, Zhao J, Cui L, Li B, Li YF. Understanding the hepatoxicity of inorganic mercury through guts: Perturbance to gut microbiota, alteration of gut-liver axis related metabolites and damage to gut integrity. Ecotoxicol Environ Saf 2021; 225:112791. [PMID: 34555721 DOI: 10.1016/j.ecoenv.2021.112791] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) brings adverse effects to the environment and human beings and inorganic mercury (IHg) is a typical hepatic toxin. This work studied the impacts of IHg on gut microbes and metabolome together with its damage to liver and gut in rats through gut microbiome, metabolomics and metallomics. Sprague Dawley (SD) rats were orally exposed to 0.4 μg/mL IHg and sacrificed after 24 h. It was found that IHg perturbed greatly on the gut microbiota, such as increased pathogenic bacteria like G. bacillus. In addition, IHg also changed gut-liver axis related metabolites, which was confirmed by the secretion of a large number of inflammatory factors in both the gut and the liver. The changed gut-liver axis related metabolites correlated well to the changes of gut microbiome. In all, besides the direct deposition in liver of Hg, the perturbance to gut microbiome and alteration of gut-liver axis related metabolites by IHg also contributed to its hepatoxicity, which provides new insights about the hepatoxicity of chemicals. The strategy applied in this work may also be used to understand the hepatoxicity of other chemicals.
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Affiliation(s)
- Xiaoying Lin
- Jilin Medical University, Jilin 132013, Jilin, China; CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Zhang
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, Guizhou, China
| | - Lina He
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Hongxin Xie
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Bo Feng
- Jilin Medical University, Jilin 132013, Jilin, China
| | - Heyun Zhu
- Jilin Medical University, Jilin 132013, Jilin, China
| | - Jiating Zhao
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liwei Cui
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bai Li
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Yu-Feng Li
- CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Abstract
We previously measured the levels of inorganic mercury, methylmercury, lead, cadmium, and manganese in the breast milk of 203 healthy Saudi mothers who participated in a cross-sectional study between 2011 and 2013. The current study aimed to (1) calculate reference values (RVs) for these metals in breast milk based on the 95th percentile of the metal and the corresponding 95% confidence interval following the approach of the German Human Biomonitoring Commission, and (2) assess the health risk associated with these metals (except lead) by determining the hazard quotient (HQ) and hazard index (HI) for breastfed infants. The risk characterization for the lead was applied using the margin of exposure (MOE) approach. Moreover, the cancer risk (CR) associated with lead was calculated. The RV95s (percentage of samples for which the value was higher than the set value) for inorganic mercury, methylmercury, total mercury, cadmium, lead, and manganese in breast milk (μg/L) were 1.5 (7.9%), 1.5 (5.4%), 2.8 (8.9%), 2.5 (8.4%), 53 (11.3%), and 22.3 (11.8%) μg/L, respectively. The methylmercury, lead, and manganese levels in the present study were higher than those reported previously. The HQ for methylmercury greater than 1 was found in 68.5% of the samples, indicating there may be a potential non-carcinogenic health risk of infant exposure to the toxic metal via breast milk consumption. Despite the high cadmium and manganese levels in breast milk, our results suggested no health risk (HQ < 1). The HI representing the combined non-carcinogenic health risk of four metals was > 1, with methylmercury (74%) being the major contributor. The estimated MOE mean value of 0.134, less than 1, indicates that our breastfed infants may be at increased risk of neurodevelopmental impairments. The CR for lead in two infants was higher than the acceptable level of 1 × 10-4. Although our results may suggest potential carcinogenic and non-carcinogenic risks of infant exposure to toxic metals through breast milk consumption, the benefits of breastfeeding are well recognized and outweigh the potential risks.
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Affiliation(s)
- Iman Al-Saleh
- Environmental Health Program, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh, 11211, Saudi Arabia.
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11
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Cossart T, Garcia-Calleja J, Worms IAM, Tessier E, Kavanagh K, Pedrero Z, Amouroux D, Slaveykova VI. Species-specific isotope tracking of mercury uptake and transformations by pico-nanoplankton in an eutrophic lake. Environ Pollut 2021; 288:117771. [PMID: 34271517 DOI: 10.1016/j.envpol.2021.117771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
The present study aims to explore the bioaccumulation and biotic transformations of inorganic (iHg) and monomethyl mercury (MMHg) by natural pico-nanoplankton community from eutrophic lake Soppen, Switzerland. Pico-nanoplankton encompass mainly bacterioplankton, mycoplankton and phytoplankton groups with size between 0.2 and 20 μm. Species-specific enriched isotope mixture of 199iHg and 201MMHg was used to explore the accumulation, the subcellular distribution and transformations occurring in natural pico-nanoplankton sampled at 2 different depths (6.6 m and 8.3 m). Cyanobacteria, diatoms, cryptophyta, green algae and heterotrophic microorganisms were identified as the major groups of pico-nanoplankton with diatoms prevailing at deeper samples. Results showed that pico-nanoplankton accumulated both iHg and MMHg preferentially in the cell membrane/organelles, despite observed losses. The ratios between the iHg and MMHg concentrations measured in the membrane/organelles and cytosol were comparable for iHg and MMHg. Pico-nanoplankton demethylate added 201MMHg (~4 and 12% per day depending on cellular compartment), although the involved pathways are to further explore. Comparison of the concentrations of 201iHg formed from 201MMHg demethylation in whole system, medium and whole cells showed that 82% of the demethylation was biologically mediated by pico-nanoplankton. No significant methylation of iHg by pico-nanoplankton was observed. The accumulation of iHg and MMHg and the percentage of demethylated MMHg correlated positively with the relative abundance of diatoms and heterotrophic microorganisms in the pico-nanoplankton, the concentrations of TN, Mg2+, NO3-, NO2-, NH4+ and negatively with the concentrations of DOC, K+, Na+, Ca2+, SO42-. Taken together the results of the present field study confirm the role of pico-nanoplankton in Hg bioaccumulation and demethylation, however further research is needed to better understand the underlying mechanisms and interconnection between heterotrophic and autotrophic microorganisms.
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Affiliation(s)
- Thibaut Cossart
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, Bvd Carl-Vogt 66, CH-1211, Geneva 4, Switzerland
| | - Javier Garcia-Calleja
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les matériaux, Pau, France
| | - Isabelle A M Worms
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, Bvd Carl-Vogt 66, CH-1211, Geneva 4, Switzerland
| | - Emmanuel Tessier
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les matériaux, Pau, France
| | - Killian Kavanagh
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, Bvd Carl-Vogt 66, CH-1211, Geneva 4, Switzerland
| | - Zoyne Pedrero
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les matériaux, Pau, France
| | - David Amouroux
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, Institut des Sciences Analytiques et de Physico-chimie pour l'Environnement et les matériaux, Pau, France
| | - Vera I Slaveykova
- Environmental Biogeochemistry and Ecotoxicology, Department F.-A. Forel for Environmental and Aquatic Sciences, Earth and Environmental Sciences, Faculty of Sciences, University of Geneva, Uni Carl Vogt, Bvd Carl-Vogt 66, CH-1211, Geneva 4, Switzerland.
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12
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Bjerregaard P, Møller LM. Exposure to methylmercury and inorganic mercury in the food does not lead to trophic magnification in the sea star Asterias rubens. Environ Pollut 2021; 285:117401. [PMID: 34051567 DOI: 10.1016/j.envpol.2021.117401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 04/19/2021] [Accepted: 05/15/2021] [Indexed: 06/12/2023]
Abstract
Methylmercury accumulated at the top of aquatic food chains constitutes a toxicological risk to humans and other top predators. Biomagnification of methylmercury takes place among vertebrates at the higher trophic levels, but this process is less elucidated in benthic invertebrates at the lower trophic levels. Therefore, we investigated the accumulation from food and elimination of methylmercury and inorganic mercury in the benthic sea star Asterias rubens (L.) - a representative of trophic level ~3 - in laboratory experiments. Sea stars fed over 49 days with contaminated mussels (Mytilus edulis) accumulate methylmercury and inorganic mercury to the highest concentrations in the digestive glands, the pyloric caeca, less in stomach, gonad, tube feet, aboral body wall and not to detectable levels in the coelomic fluid. Concerning whole body contents, steady states were reached for both methylmercury and inorganic mercury during the 7-week feeding period and the sea stars reached approximately ½ and ¼ of the concentrations in the mussel food for the two mercury forms, respectively. Half-lives for the elimination of the two mercury forms varied between 45 and 173 days in a 140-d elimination period following the feeding period; inorganic mercury was eliminated faster than methylmercury. Examination of total mercury concentrations in field-collected sea stars confirmed this lack of trophic magnification in relation to the major food items, soft parts of molluscs. We suggest that mercury is not trophically magnified in sea stars 1) because they eliminate methylmercury faster than larger fish and decapod crustaceans and 2) maybe more importantly, because inorganic mercury with its faster elimination constitutes a larger fraction of the total mercury in the food at the lower trophic levels - as opposed to methylmercury which dominates at the higher trophic levels.
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Affiliation(s)
- Poul Bjerregaard
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense, Denmark.
| | - Lise Marianne Møller
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230, Odense, Denmark
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13
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Dos Santos Chemelo V, Bittencourt LO, Aragão WAB, Dos Santos SM, Souza-Rodrigues RD, Ribeiro CHMA, Monteiro MC, Lima RR. Long-Term Exposure to Inorganic Mercury Leads to Oxidative Stress in Peripheral Blood of Adult Rats. Biol Trace Elem Res 2021; 199:2992-3000. [PMID: 32997227 DOI: 10.1007/s12011-020-02411-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 09/23/2020] [Indexed: 12/16/2022]
Abstract
Mercury chloride (HgCl2) is a compound found in the environment that presents low risk due to low liposolubility. Considering the importance of blood as access rout to the systemic distribution of this toxicant to the organism as well as functions performed by it, this study aimed to investigate the effects of HgCl2 on the peripheral blood of rats, evaluating the oxidative biochemistry, blood count, and morphology of cell populations. For this, 20 adult Wistar male rats were divided into control (n = 10) and exposed (n = 10) groups and received distilled water or HgCl2 at a dose of 0.375 mg/kg for 45 days, respectively, through intragastric gavage. Then, the animals were euthanized and the blood was collected for total mercury (Hg) levels determination, complete blood and reticulocyte count, oxidative biochemistry by Trolox Equivalent Antioxidant Capacity (TEAC), reduced glutathione (GSH) levels, superoxide dismutase activity (SOD), thiobarbituric acid reactive substances (TBARS), and nitric oxide (NO), in blood cells and plasma. Long-term exposure increased total Hg in plasma and blood cells. In blood cells, only TEAC has decreased; in plasma, the HgCl2 increased TBARS and NO levels, followed by a decrease in TEAC and GSH levels. There were no quantitative changes in reticulocytes, erythrocytes, and hemoglobin; however, the number of leukocytes have increased and platelets have decreased. Our results suggest that even in the face of low toxicity when compared with other mercury species, HgCl2 at low doses is able to modulate the systemic redox balance and affect some blood cell populations.
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Affiliation(s)
- Victória Dos Santos Chemelo
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Rua Augusto Corrêa n° 1, Campus do Guamá, Belém, Pará, 66075-110, Brazil
| | - Leonardo Oliveira Bittencourt
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Rua Augusto Corrêa n° 1, Campus do Guamá, Belém, Pará, 66075-110, Brazil
| | - Walessa Alana Bragança Aragão
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Rua Augusto Corrêa n° 1, Campus do Guamá, Belém, Pará, 66075-110, Brazil
| | - Sávio Monteiro Dos Santos
- Laboratory of Clinical Immunology and Oxidative Stress, Pharmacy Faculty, Institute of Health Science, Federal University of Pará, Belém, Pará, Brazil
| | - Renata Duarte Souza-Rodrigues
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Rua Augusto Corrêa n° 1, Campus do Guamá, Belém, Pará, 66075-110, Brazil
| | | | - Marta Chagas Monteiro
- Laboratory of Clinical Immunology and Oxidative Stress, Pharmacy Faculty, Institute of Health Science, Federal University of Pará, Belém, Pará, Brazil
| | - Rafael Rodrigues Lima
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Rua Augusto Corrêa n° 1, Campus do Guamá, Belém, Pará, 66075-110, Brazil.
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14
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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15
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Ma HH, Ding YN, Wang A, Li X, Wang Y, Shi FG, Lu YF. Cinnabar protects serum-nutrient starvation induced apoptosis by improving intracellular oxidative stress and inhibiting the expression of CHOP and PERK. Biochem Biophys Rep 2021; 27:101055. [PMID: 34258395 PMCID: PMC8255187 DOI: 10.1016/j.bbrep.2021.101055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 04/30/2021] [Accepted: 06/10/2021] [Indexed: 02/06/2023] Open
Abstract
Cinnabar has been used for treatment of various disorders for thousands of years. The medical use of cinnabar, however, has been controversial because of its heavy metal mercury content. A large quantity of studies indicate that the toxicity of cinnabar is far below other inorganic or organic mercury-containing compounds. Yet, the underlying molecular basis has remained unresolved. Here, we investigated the beneficial effects of cinnabar on serum-nutrient starvation-elicited cell injury. Our findings showed that treatment of human renal proximal tubular cells (HK-2) with 4 nM cinnabar effectively inhibited nutrient deprivation induced apoptosis, reduced intracellular reactive oxygen species generation and increased GSH content, which was contrary to the exacerbated apoptotic cell death and oxidative stress in cells treated with HgCl2 at equal mercury concentration. In addition, cinnabar exerted robust antioxidative and antiapoptotic effects in cells under dual challenges of nutrient deprivation and treatment of H2O2. The protein expression levels of both CHOP and PERK were remarkably down-regulated in the cells treated with cinnabar compared to the control cells or cells treated with HgCl2. Overall, our data indicates that cinnabar at low concentration exerts anti-oxidative stress and anti-apoptosis effects by inhibiting the expression of the endoplasmic reticulum stress pathway proteins CHOP and PERK.
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Affiliation(s)
- Hong-Hong Ma
- Joint International Research Laboratory of Ethnomedicine, and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563000, China
| | - Yan-Nan Ding
- Joint International Research Laboratory of Ethnomedicine, and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563000, China
| | - Ao Wang
- Zunyi Institute of Product Quality Inspection and Testing, Zunyi, 563000, China
| | - Xia Li
- Joint International Research Laboratory of Ethnomedicine, and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563000, China
| | - Yang Wang
- Joint International Research Laboratory of Ethnomedicine, and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563000, China
| | - Fu-Guo Shi
- Joint International Research Laboratory of Ethnomedicine, and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563000, China
| | - Yuan-Fu Lu
- Joint International Research Laboratory of Ethnomedicine, and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563000, China
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16
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Abstract
This review paper investigates a specific environmental-disease interaction between mercury exposure and Alzheimer's disease hallmarks. Alzheimer's disease is a neurodegenerative disorder affecting predominantly the memory of the affected individual. It prevails mostly in the elderly, rendering many factors as possible causative agents, which potentially contribute to the disease pathogenicity cumulatively. Alzheimer's disease affects nearly 50 million people worldwide and is considered one the most devastating diseases not only for the patient, but also for their families and caregivers. Mercury is a common environmental toxin, found in the atmosphere mostly due to human activity, such as coal burning for heating and cooking. Natural release of mercury into the atmosphere occurs by volcanic eruptions, in the form of vapor, or weathering rocks. The most toxic form of mercury to humans is methylmercury, to which humans are exposed to by ingestion of fish. Methylmercury was found to exert its toxic effects on different parts of the human body, with predominance on the brain. There is no safe concentration for mercury in the atmosphere, even trace amounts can elicit harm to humans in the long term. Mercury's effect on Alzheimer's disease hallmarks formation, extracellular senile plaques and intracellular neurofibrillary tangles, has been widely studied. This review demonstrates the involvement of mercury, in its different forms, in the pathway of amyloid beta deposition and tau tangles formation. It aims to understand the link between mercury exposure and Alzheimer's disease so that, in the future, prevention strategies can be applied to halt the progression of this disease.
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Affiliation(s)
- Jihan Azar
- Institute of Global Health and Human Ecology, School of Sciences and Engineering, The American University in Cairo, P.O. Box: 74, New Cairo, Egypt
| | - Mohamed H Yousef
- Biotechnology Graduate Program, School of Sciences and Engineering, The American University in Cairo, Cairo, Egypt
| | - Hassan A N El-Fawal
- Institute of Global Health and Human Ecology, School of Sciences and Engineering, The American University in Cairo, P.O. Box: 74, New Cairo, Egypt
| | - Anwar Abdelnaser
- Institute of Global Health and Human Ecology, School of Sciences and Engineering, The American University in Cairo, P.O. Box: 74, New Cairo, Egypt.
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17
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Ku P, Tsui MTK, Liu S, Corson KB, Williams AS, Monteverde MR, Woerndle GE, Hershey AE, Rublee PA. Examination of mercury contamination from a recent coal ash spill into the Dan River, North Carolina, United States. Ecotoxicol Environ Saf 2021; 208:111469. [PMID: 33091769 DOI: 10.1016/j.ecoenv.2020.111469] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Coal ash spills occasionally occur due to the accidental failure of surface impoundments, and toxic metal-laden ash can pose a serious health threat to adjacent aquatic ecosystems. Here, we performed an investigation into longitudinal variations of mercury (Hg) contamination in the Dan River (North Carolina, United States) about 17 and 29 months after a February 2014 coal ash spill incident, in which the reported Hg concentrations in the spilled coal ash (210 ng/g) were 1-2 orders of magnitude higher than the river sediments (2-61 ng/g). We examined total Hg (THg) and methyl Hg (MeHg) in sediments from 0 to 65 km downstream of the spill, and found that most of the variations of THg and MeHg in surface sediments (0-16 cm) could be well accounted by the organic matter content and appeared to be not contaminated by Hg derived from coal ash. In examining MeHg bioaccumulation in invertebrates (aquatic and riparian) and fish in the Dan River and fish in a reservoir downstream of Dan River, we found no evidence of elevated MeHg bioaccumulation due to the 2014 coal ash spill. Thus, we concluded that Hg contamination from the coal ash spill is largely absent in the Dan River for both surface sediments and biota within the first three years of spill (until 2017), even though the majority of coal ash may be buried deeper in the sediment in the river channel and/or the downstream reservoir. Alternatively, the Hg associated with the coal ash is largely not bioavailable for extensive microbial Hg methylation. The findings provide useful insights into remediation strategies for this incident and other coal ash spills.
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Affiliation(s)
- Peijia Ku
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Martin Tsz-Ki Tsui
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA.
| | - Songnian Liu
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Kimber B Corson
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Ashley S Williams
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Matthew R Monteverde
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Glenn E Woerndle
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Anne E Hershey
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
| | - Parke A Rublee
- Department of Biology, University of North Carolina at Greensboro, Greensboro, NC 27402, USA
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18
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Mahbub KR, King WL, Siboni N, Nguyen VK, Rahman MM, Megharaj M, Seymour JR, Franks AE, Labbate M. Long-lasting effect of mercury contamination on the soil microbiota and its co-selection of antibiotic resistance. Environ Pollut 2020; 265:115057. [PMID: 32806457 DOI: 10.1016/j.envpol.2020.115057] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 05/11/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Antibiotic resistance genes (ARGs) in the environment are an exposure risk to humans and animals and is emerging as a global public health concern. In this study, mercury (Hg) driven co-selection of ARGs was investigated under controlled conditions in two Australian non-agricultural soils with differing pH. Soils were spiked with increasing concentrations of inorganic Hg and left to age for 5 years. Both soils contained ARGs conferring resistance to tetracycline (tetA, tetB), sulphonamides (sul1), trimethoprim (dfrA1) and the ARG indicator class 1 integron-integrase gene, intI1, as measured by qPCR. The last resort antibiotic vancomycin resistance gene, vanB and quinolone resistance gene, qnrS were not detected. Hg driven co-selection of several ARGs namely intI1, tetA and tetB were observed in the alkaline soil within the tested Hg concentrations. No co-selection of the experimental ARGs was observed in the neutral pH soil. 16S rRNA sequencing revealed proliferation of Proteobacteria and Bacteriodetes in Hg contaminated neutral and alkaline soils respectively. Multivariate analyses revealed a strong effect of Hg, soil pH and organic carbon content on the co-selection of ARGs in the experimental soils. Additionally, although aging caused a significant reduction in Hg content, agriculturally important bacterial phyla such as Nitrospirae did not regrow in the contaminated soils. The results suggest that mercury can drive co-selection of ARGs in contaminated non-agricultural soils over five years of aging which is linked to soil microbiota shift and metal chemistry in the soil.
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Affiliation(s)
| | - William L King
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia; Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Nachshon Siboni
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Viet Khue Nguyen
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia; Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Mohammad Mahmudur Rahman
- Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation, The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Justin R Seymour
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Ashley E Franks
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, 3086, Australia; Centre for Future Landscapes, La Trobe University, Bundoora, VIC, 3086, Australia
| | - Maurizio Labbate
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
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19
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Ayyat MS, Ayyat AMN, Abd El-Latif KM, Hessein AAA, Al-Sagheer AA. Inorganic mercury and dietary safe feed additives enriched diet impacts on growth, immunity, tissue bioaccumulation, and disease resistance in Nile tilapia (Oreochromis niloticus). Aquat Toxicol 2020; 224:105494. [PMID: 32422488 DOI: 10.1016/j.aquatox.2020.105494] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/12/2020] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
Little is known about the impacts of dietary exposure to inorganic mercury (Hg) for a long duration on the health indicators, growth, and disease resistance in Oreochromis niloticus. Accordingly, the current study was designed to assess the effects of Hg contaminated diets on blood biochemistry, growth, chemical composition, Hg bioaccumulation in the tissues, histopathology of liver and head kidneys, and disease resistance to Aeromonas hydrophila of O. niloticus. Also, the efficiency of citronella oil, geranium oil (GO), curcumin (CUR), Bacillus toyonensis (BT), and Bacillus subtilis (BS) as dietary supplements on reversing the negative impacts of Hg were assessed. A total of 240 tilapia fingerlings were assigned to eight dietary treatments fed on the basal diet (G1), G1 diet contaminated with 50 ppm Hg (G2), whereas the other groups fed the G2 diet and enriched with 400 mg CO (G3), 400 mg GO (G4), 200 mg CUR (G5), 7 × 107 cells BT (G6), 7 × 107 cells BS (G7), and 7 × 107 BT + BS/ kg diet (G8) for 16 weeks. The obtained results showed that fish fed on the G2 diet had significantly impaired growth performance indicators, blood parameters, and resistance to bacterial infection compared with fish in the control group. Additionally, distinct pathological perturbations in liver and head kidneys were observed. In contrast, fish groups G3 to G8 had a significant enhancement in the growth performance, Hg bioaccumulation in fish tissues, blood biochemistry, and resistance against A. hydrophila infection compared with fish in the G2 group. Maximum improvement was recorded in G5, G6, and G8. Conclusively, from both health and an economic point of view, these results suggested that several benefits might be gained by adding these additives, especially CUR, BT, and BT + BS, on growth enhancement and ameliorating Hg negative impacts in O. niloticus.
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Affiliation(s)
- Mohamed Salah Ayyat
- Animal Production Department, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt.
| | - Ahmed Mohamed Nabil Ayyat
- Department of Fish Nutrition and Feed Technology, Central Laboratory for Aquaculture Research, Abassa, Abu Hammad, Sharkia, Egypt
| | | | - Amira A A Hessein
- Department of Fish Nutrition and Feed Technology, Central Laboratory for Aquaculture Research, Abassa, Abu Hammad, Sharkia, Egypt
| | - Adham A Al-Sagheer
- Animal Production Department, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
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20
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O'Donoghue JL, Watson GE, Brewer R, Zareba G, Eto K, Takahashi H, Marumoto M, Love T, Harrington D, Myers GJ. Neuropathology associated with exposure to different concentrations and species of mercury: A review of autopsy cases and the literature. Neurotoxicology 2020; 78:88-98. [PMID: 32092311 DOI: 10.1016/j.neuro.2020.02.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/16/2020] [Accepted: 02/21/2020] [Indexed: 11/20/2022]
Abstract
BACKGROUND Human exposure to mercury (Hg) is widespread and both organic and inorganic Hg are routinely found in the human brain. Millions of people are exposed to methyl Hg (MeHg) due to the consumption of fish and to inorganic Hg from dental amalgams, small scale gold mining operations, use of Hg containing products, or their occupations. Neuropathology information associated with exposures to different species of Hg is primarily based on case reports of single individuals or collections of case studies involving a single species of Hg at toxic exposure levels such as occurred in Japan and Iraq. METHODS/RESULTS This study brings together information on the neuropathological findings and deposition of Hg in the central nervous system of people exposed to different species of Hg at varying concentrations. The low dose exposures were lifetime exposures while the high dose exposures were generally acute or short term by different exposure routes with survival lasting various lengths of time. Total and inorganic Hg deposits were identified in formalin-fixed, paraffin embedded tissues from both low and high exposure Hg cases. Low concentration exposures were studied in adult brains from Rochester, New York (n = 4) and the Republic of Seychelles (n = 17). Rochester specimens had mean total Hg concentrations of 16-18 ppb in the calcarine, rolandic, and cerebellar cortices. Inorganic Hg averaged between 5-6 ppb or 30-37% for the cerebral and cerebellar cortices of the Rochester subjects. Total Hg was approximately 10-fold higher in specimens from Seychelles, where consumption of ocean fish is high and consequently results in exposure to MeHg. The predominant Hg species was MeHg in both the Rochester and Seychelles brain specimens. Histologically, cerebral and cerebellar cortices from Rochester and Seychelles specimens were indistinguishable. High concentration exposures were studied in brains from four adults who were autopsied at variable time periods after exposure to organic Hg (methyl or dimethyl) or inorganic Hg (inhaled vapor or intravenous injection of metallic Hg). In contrast to the Seychellois adults, these individuals had acute or subacute exposures to lethal or significantly higher concentrations. The pattern of Hg deposition differed between subjects with high organic Hg exposure and high inorganic Hg exposure. In the organic Hg cases, glia (astrocytes and microglia) and endothelial cells accumulated more Hg than neurons and there were minimal Hg deposits in cerebellar granule and Purkinje cells, anterior horn motor neurons, and neocortical pyramidal neurons. In the inorganic Hg cases, Hg was seen predominantly in neurons, vascular walls, brainstem, and cerebellar and cerebral deep gray nuclei. The presence of inorganic Hg in neural and neural supporting cells in the four high exposure Hg cases was not closely correlated with cellular pathology; particularly in the inorganic Hg cases. CONCLUSIONS Different Hg species are associated with differing neuropathological patterns. No neuropathological abnormalities were present in the brains of either Rochester or Seychelles residents despite substantial differences in dietary MeHg exposure. Increasing concentrations of inorganic Hg were present in the brain of relatively low exposure subjects with increasing age.
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Affiliation(s)
- John L O'Donoghue
- Department of Environmental Medicine, University of Rochester Medical Center, School of Medicine and Dentistry, Box EHSC, 601 Elmwood Ave, Rochester, NY 14642, United States.
| | - Gene E Watson
- Department of Environmental Medicine, University of Rochester Medical Center, School of Medicine and Dentistry, Box EHSC, 601 Elmwood Ave, Rochester, NY 14642, United States; Eastman Institute for Oral Health and Department of Pharmacology and Physiology, University of Rochester Medical Center, School of Medicine and Dentistry, Box 683, 601 Elmwood Ave, Rochester, NY, 14642, United States
| | - Rubell Brewer
- Victoria Hospital and the Ministry of Health, Seychelles
| | - Grazyna Zareba
- Department of Environmental Medicine, University of Rochester Medical Center, School of Medicine and Dentistry, Box EHSC, 601 Elmwood Ave, Rochester, NY 14642, United States
| | - Komyo Eto
- Formerly Director General, National Institute for Minamata Disease, Ministry of the Environment, 4058-18, Hama, Minamata City, Kumamoto Prefecture, 867-0008, Japan
| | - Hitoshi Takahashi
- Department of Pathology, Brain Research Institute, Niigata University, 1-757 Asahimachi, Chuo-ku, Niigata, 951-8585, Japan
| | - Masumi Marumoto
- Toxicologic Pathology Section, Department of Basic Medical Sciences, National Institute for Minamata Disease, Ministry of the Environment, 4058-18, Hama, Minamata City, Kumamoto Prefecture, 867-0008, Japan
| | - Tanzy Love
- Department of Biostatistics and Computational Biology, University of Rochester Medical Center, School of Medicine and Dentistry, Box 630, 601 Elmwood Ave, Rochester, NY, 14642, United States
| | - Donald Harrington
- Department of Biostatistics and Computational Biology, University of Rochester Medical Center, School of Medicine and Dentistry, Box 630, 601 Elmwood Ave, Rochester, NY, 14642, United States
| | - Gary J Myers
- Department of Environmental Medicine, University of Rochester Medical Center, School of Medicine and Dentistry, Box EHSC, 601 Elmwood Ave, Rochester, NY 14642, United States; Department of Neurology, Child Neurology, University of Rochester Medical Center, School of Medicine and Dentistry, Box 631, 601 Elmwood Avenue, Rochester, NY 14642, United States; Department of Pediatrics, University of Rochester Medical Center, School of Medicine and Dentistry, Box 631, 601 Elmwood Ave, Rochester, NY, 14642, United States
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Yu ZG, Zhang L, Wu Y, Jin B. Efflux behavior of inorganic mercury and methylmercury in the marine copepod Tigriopus japonicus. Sci Total Environ 2020; 703:135655. [PMID: 31767324 DOI: 10.1016/j.scitotenv.2019.135655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/17/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
Marine copepods play an important role in transferring mercury to higher trophic levels in aquatic ecosystems. Exposure time is an important environmental parameter that potentially influences the bioaccumulation and biomagnification of Hg in copepods, which increases the uncertainty in risk assessments of Hg in food chains. In the present study, we employed the radiotracer technique to evaluate the efflux behavior of inorganic mercury [Hg(II)] and methylmercury (MeHg), and the effects of exposure time in a population of Tigriopus japonicus copepods. Exposure treatments were compared to understand the effects of exposure time (1 d, 3 d, and 7 d) on the release routes and efflux rate constants (ke) of Hg in copepods. During a depuration period of 5 d, the ke value of Hg(II) in the three exposure treatments ranged from 0.190-0.330 d-1, while the ke of MeHg was generally slower and ranged from 0.031-0.051 d-1. The exposure time significantly affected the efflux rates of Hg(II), i.e., a longer exposure time caused a higher retained Hg(II) burden in copepods, while no significant changes were observed in the MeHg treatments. The release routes of Hg in T. japonicus included excretion, feces production, and reproduction. In all the treatments, the excretion of Hg was the most important release route. The relative contribution of reproduction significantly increased in the MeHg exposure treatments, while the contribution of water excretion decreased with exposure time. Our study demonstrated that the retention of Hg(II) and the maternal transfer of MeHg were time-dependent and significantly affected by exposure time. Long-term exposure caused a decrease in the ke of Hg(II) and increase in the contribution of MeHg transfer to nauplii, thereby indicating an increasing risk of biological transmission of Hg under long-term exposure.
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Affiliation(s)
- Zhi-Guo Yu
- School of Hydrology and Water Resources, Nanjing University of Information Science and Technology, 210044 Nanjing, China; State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Le Zhang
- School of Hydrology and Water Resources, Nanjing University of Information Science and Technology, 210044 Nanjing, China
| | - Yun Wu
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CIC-AEET), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China.
| | - Biao Jin
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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22
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Kern JK, Geier DA, Homme KG, Geier MR. Examining the evidence that ethylmercury crosses the blood-brain barrier. Environ Toxicol Pharmacol 2020; 74:103312. [PMID: 31841767 DOI: 10.1016/j.etap.2019.103312] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 12/06/2019] [Accepted: 12/06/2019] [Indexed: 06/10/2023]
Abstract
Scientific research can provide us with factual, repeatable, measurable, and determinable results. As such, scientific research can provide information that can be used in the decision-making process in the care of patients and in public policy. Although it has been suggested that ethylmercury (C2H5Hg+)-containing compounds do not cross the blood-brain barrier (BBB), this review examines the literature that addresses the question as to whether ethylmercury-containing compounds cross the BBB. The review will begin with cellular studies that provide evidence for the passive and active transport of mercury species across the BBB. Then, animal and clinical studies will be presented that specifically examine whether mercury accumulates in the brain after exposure to ethylmercury-containing compounds or Thimerosal (an ethylmercury-containing compound used as a preservative in vaccines and other drugs that metabolizes or degrades to ethylmercury-containing compounds and thiosalicylate). The results indicate that ethylmercury-containing compounds are actively transported across membranes by the L (leucine-preferring)-amino acid transport (LAT) system, the same as methylmercury-containing compounds. Further, 22 studies from 1971 to 2019 show that exposure to ethylmercury-containing compounds (intravenously, intraperitoneally, topically, subcutaneously, intramuscularly, or intranasally administered) results in accumulation of mercury in the brain. In total, these studies indicate that ethylmercury-containing compounds and Thimerosal readily cross the BBB, convert, for the most part, to highly toxic inorganic mercury-containing compounds, which significantly and persistently bind to tissues in the brain, even in the absence of concurrent detectable blood mercury levels.
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Affiliation(s)
- Janet K Kern
- Institute of Chronic Illnesses, Inc, Silver Spring, MD, USA; CoMeD, Inc, Silver Spring, MD, USA; CONEM US Autism Research Group, Allen, TX, USA.
| | - David A Geier
- Institute of Chronic Illnesses, Inc, Silver Spring, MD, USA; CoMeD, Inc, Silver Spring, MD, USA
| | - Kristin G Homme
- International Academy of Oral Medicine and Toxicology, ChampionsGate, FL, USA
| | - Mark R Geier
- Institute of Chronic Illnesses, Inc, Silver Spring, MD, USA; CoMeD, Inc, Silver Spring, MD, USA
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Wu Q, He X, Zhou S, Shi F, Lu Y. Role of PEPT1in the transport of cinnabar in Caco-2 cells. Toxicol In Vitro 2019; 63:104747. [PMID: 31838184 DOI: 10.1016/j.tiv.2019.104747] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 11/24/2019] [Accepted: 12/10/2019] [Indexed: 01/01/2023]
Abstract
Cinnabar, a mercury-containing mineral medicine, has been used as an ingredient in Traditional Chinese Medicines for treatment of various diseases for thousands of years and is still widely used today. The toxicity of cinnabar is much less than other mercury-containing compounds. This study aimed to evaluate the possible role of oligopeptide transporter1 (PEPT1) in intestinal uptake of cinnabar. Thus, the Caco-2 cell model was employed to investigate the differential transport levels and the probable transporter involved in the transport of cinnabar, mercury sulfide (HgS) and mercury chloride (HgCl2). Cells were incubated with the same molar concentration of cinnabar, HgS or HgCl2 and then the inorganic mercury content of apical (AP), cellular and basolateral (BL) side of the cell was measured by ultra-high liquid chromatography-inductively coupled plasma mass spectrometry (UPLC-ICP/MS) after the treatment, respectively. Their transportation levels were also investigated when pH was changed to 5.5 in AP side to define the role of the H+ dependent transporter. Effects of cinnabar, HgS or HgCl2 on transporter mRNA and protein expression levels were assayed by RT-PCR and Western-blot method, respectively. The possible transporter involved in the transport was examined by siRNA silencing and chemical inhibition. The results showed that the levels of inorganic mercury in the BL side for cinnabar and HgS were 49.39% and 30.41% of that in HgCl2 group. The transport levels of cinnabar and HgCl2 were significantly increased when the pH was changed to 5.5 on the AP side as compared with the control group (pH 7.4). Cinnabar significantly decreased the mRNA and protein expression of PEPT1. Transport levels of cinnabar were significantly decreased by PEPT1-siRNA and chemical inhibition of PEPT1. The present study demonstrates that PEPT1 may be an important transporter in the entry of cinnabar into the intestinal epithelium, and intestinal transport levels of cinnabar and HgS was lower than that of HgCl2.
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Affiliation(s)
- Qing Wu
- Key Lab of the Basic Pharmacology of the Ministry of Education, Zunyi Medical University, 6 West Xue-Fu Road, Zunyi City, Guizhou 563000, China; Department of Clinical Pharmacy, School of Pharmacy, Zunyi Medical University, 6 West Xue-Fu Road, Zunyi City, Guizhou 563000, China
| | - Xi He
- Key Lab of the Basic Pharmacology of the Ministry of Education, Zunyi Medical University, 6 West Xue-Fu Road, Zunyi City, Guizhou 563000, China
| | - Shaojun Zhou
- Zunyi Institute of Product Quality Inspection and testing, 126 Shanghai Road, Zunyi city, Guizhou 563000, China
| | - Fuguo Shi
- Key Lab of the Basic Pharmacology of the Ministry of Education, Zunyi Medical University, 6 West Xue-Fu Road, Zunyi City, Guizhou 563000, China.
| | - Yuanfu Lu
- Key Lab of the Basic Pharmacology of the Ministry of Education, Zunyi Medical University, 6 West Xue-Fu Road, Zunyi City, Guizhou 563000, China.
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24
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Kolbinger V, Engström K, Berger U, Bose-O'Reilly S. Polymorphisms in potential mercury transporter ABCC2 and neurotoxic symptoms in populations exposed to mercury vapor from goldmining. Environ Res 2019; 176:108512. [PMID: 31195293 DOI: 10.1016/j.envres.2019.05.043] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 05/09/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Artisanal small-scale gold miners have high levels of mercury in human specimens often above recommended threshold values. There are differences reported in the manifestation of neurological symptoms of individuals with a comparable level of exposure to mercury, suggesting a genetic component influencing the susceptibility to mercury neurotoxicity. OBJECTIVE To investigate associations between polymorphisms (rs1885301, rs717620, rs2273697) in the potential Hg-transporter ABCC2 gene and neurological effects. METHODS 968 participants from the Philippines, Indonesia, Tanzania and Zimbabwe were included in this study (age 12-59 years). For the statistical analysis the countries were categorized into Africa (Philippines, Indonesia) and Asia (Tanzania, Zimbabwe). Study participants were from three exposure groups: without mercury exposure from goldmining (n = 129); living in mercury-contaminated areas (n = 281) and mercury working exposure (n = 558). To identify chronic inorganic mercury intoxication we applied a modified neurological score sum including eight binary coded parameters (from anamnestic, clinical and neurophysiological examinations). Associations between genotype and neurological score sum, as well as between genotype and separate neurological tests (ataxia of gait, dysdiadochokinesia, ataxia heel to shin, pencil tapping test and matchbox test) were evaluated. RESULTS We found that ABCC2 genotype were associated with performance on certain neurological tests: for rs1885301, A-allele carriers in the African populations showed significantly worse performance than GG carriers on the pencil tapping test; whereas for rs2273697, A-allele carriers in the African and Asian populations showed a significantly better performance than GG carriers on this test. When including an interaction term between genotype and exposure subgroup, interaction effects were also seen for the pencil tapping test and matchbox tests for rs2273697 in Asia. CONCLUSIONS The results suggest that certain ABCC2 polymorphisms may influence the neurotoxic effects in mercury-burdened individuals. ABCC2 alleles associated with worse neurological performance in the present study. These alleles have previously been correlated with higher levels of urinary mercury concentrations in the same cohort. Taken together, these associations between ABCC2 genotype, mercury levels, and neurological effects support the hypothesis that some ABCC2 genotypes may have a higher neurotoxic potential, although further functional studies are needed to prove causation.
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Affiliation(s)
- Vitus Kolbinger
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine; University Hospital Munich, Ziemssenstr. 1, D-80336, Munich, Germany.
| | - Karin Engström
- Department of Laboratory Medicine, Division of Occupational and Environmental Medicine, Lund University, 221 85, Lund, Sweden.
| | - Ursula Berger
- Department of Medical Information Sciences, Biometrics, and Epidemiology IBE, Ludwig-Maximilians-University Munich, Marchioninistr. 15, D-81377, Munich, Germany.
| | - Stephan Bose-O'Reilly
- Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine; University Hospital Munich, Ziemssenstr. 1, D-80336, Munich, Germany; Institute of Public Health, Medical Decision Making and Health Technology Assessment, Department of Public Health, Health Services Research and Health Technology Assessment, UMIT (University for Health Sciences, Medical Informatics and Technology), EWZ 1, A6060, Hall i.T., Austria.
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25
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Queipo-Abad S, González PR, Martínez-Morillo E, Davis WC, García Alonso JI. Concentration of mercury species in hair, blood and urine of individuals occupationally exposed to gaseous elemental mercury in Asturias (Spain) and its comparison with individuals from a control group formed by close relatives. Sci Total Environ 2019; 672:314-323. [PMID: 30959298 DOI: 10.1016/j.scitotenv.2019.03.367] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/22/2019] [Accepted: 03/23/2019] [Indexed: 06/09/2023]
Abstract
Between November 19th, 2012 and December 3rd, 2012, 50 workers were intoxicated with gaseous Hg in San Juan de Nieva (Asturias, Spain) during the maintenance of a heat exchanger of a zinc manufacturer. We have quantified the concentration of methylmercury (MeHg), ethylmercury (EtHg) and Hg(II) in blood, hair and urine samples of those individuals taken three years after the accident. Blood, hair and urine of their closest relatives were also analyzed to assess whether the mercury burden present in the intoxicated individuals was due to the occupational exposure or to environmental or lifestyle-related factors. The determination of the mercury species in the samples was carried out applying multiple spiking Isotope Dilution GC-ICP-MS. This procedure corrects for possible interconversion reactions between the Hg species during the sample preparation procedure. Linear correlations were observed for both groups when plotting MeHg in blood vs MeHg in hair, and MeHg in hair vs Hg (II) in urine. The concentrations of Hg species in the intoxicated individuals were not significantly different from those obtained in the control group except for MeHg in blood. Significantly higher levels of MeHg in blood were obtained in some of the intoxicated individuals who had not consumed fish or seafood since the accident. A different correlation between MeHg in hair and MeHg in blood was obtained for these individuals compared to the control group who showed a hair-to-blood ratio consistent with the reported value for people exposed to Hg via fish consumption. Our results suggest that ingested MeHg followed the same pathway of deposition in hair in exposed and non-exposed individuals. However, the exposed individuals with high MeHg levels in blood showed a significantly different extent of MeHg deposition in hair compared to the control group.
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Affiliation(s)
- Silvia Queipo-Abad
- Department of Physical and Analytical Chemistry, University of Oviedo, Julián Clavería, 8, 33006 Oviedo, Spain
| | - Pablo Rodríguez González
- Department of Physical and Analytical Chemistry, University of Oviedo, Julián Clavería, 8, 33006 Oviedo, Spain.
| | - Eduardo Martínez-Morillo
- Service of Clinical Biochemistry, Laboratory of Medicine, Central University Hospital of Asturias (HUCA), 33011 Oviedo, Spain
| | - W Clay Davis
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - José Ignacio García Alonso
- Department of Physical and Analytical Chemistry, University of Oviedo, Julián Clavería, 8, 33006 Oviedo, Spain
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26
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Xu X, Yan M, Liang L, Lu Q, Han J, Liu L, Feng X, Guo J, Wang Y, Qiu G. Impacts of selenium supplementation on soil mercury speciation, and inorganic mercury and methylmercury uptake in rice (Oryza sativa L.). Environ Pollut 2019; 249:647-654. [PMID: 30933762 DOI: 10.1016/j.envpol.2019.03.095] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 02/28/2019] [Accepted: 03/23/2019] [Indexed: 05/09/2023]
Abstract
Rice grain is known to accumulate methylmercury (MeHg) and has been confirmed to be the major pathway of MeHg exposure to residents in mercury (Hg) mining areas in China. Selenium (Se) supplementation has been proven to be effective in mitigating the toxicity of Hg. To understand how Se supplementation influences soil Hg speciation, a wide range of Se (0-500 mg/kg) was applied to Hg polluted paddy soils in this study, which decreased MeHg concentration in soil from 2.95 ± 0.36 to 0.69 ± 0.16 μg/kg (or 77%). After Se addition, humic acid state Hg (F4) was transformed into strong-complexed state Hg (F5), indicating that Hg bound up to the non-sulfur functional groups of humic acid (non-RSH) was released and reabsorbed by strong binding Se functional group (F5). As a result, inorganic Hg (IHg) was reduced by >48%, 18%, and 80% in root, stem, and grain, respectively, however, the reduction was not apparent in leaf. Substantial reductions were also found for MeHg in grain and root, but not in stem and leaf. Soil is suggested to be the main source of both MeHg and IHg in rice grain. Such a finding may provide an idea for improving Hg-polluted paddies through controlling soil IHg and MeHg. Further research on the molecular structure of the strong-complexed Hg in F5 should be conducted to elucidate the mechanism of Hg-Se antagonism.
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Affiliation(s)
- Xiaohang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Min Yan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | | | - Qinhui Lu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | | | - Lin Liu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Jianyang Guo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Yajie Wang
- College of Food Safety, Guizhou Medical University, Guiyang, 550025, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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Liu Q, Xu X, Zeng J, Huang W, Xu X, Shou L, Chen Q. Development of marine water quality criteria for inorganic mercury in China based on the retrievable toxicity data and a comparison with relevant criteria or guidelines. Ecotoxicology 2019; 28:412-421. [PMID: 30874993 DOI: 10.1007/s10646-019-02032-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/26/2019] [Indexed: 05/24/2023]
Abstract
The development of marine water quality criteria (WQC) in China has been insufficient because data on the toxicity of pollutants for marine organisms based on the species sensitivity distribution (SSD) method are lacking. The Chinese aquatic environmental quality standards, including those for seawater, were derived from the developed countries. Therefore, establishing Chinese marine WQC is crucial for identifying the sensitivity of marine species in China and will improve their protection from threats. Mercury (Hg) is one of the primary pollutants commonly exceeding Chinese seawater quality standards. Several countries have developed their marine WQC for inorganic Hg in the past decades, but no study has been conducted in China. In this study, 45 acute toxicity and 14 chronic toxicity data of inorganic Hg on the marine species which inhabit in China were obtained mainly from the ECOTOX database, the CNKI, and the Google Scholar. The acute and chronic hazardous concentrations for 5% of the species (HC5) were calculated based on the best-fit distribution model Sweibull. The criteria for maximum and continuous concentrations of 1.30 and 0.66 μg/L, respectively, for inorganic Hg to protect marine organisms in China were derived by halving the HC5 values. The criteria were comparable to those of the United States, Australia, and the European Union countries, indicating the general applicability of WQCs developed based on the classical SSD method using different species groups. This study may provide valuable information for assessing marine ecological risk in China.
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Affiliation(s)
- Qiang Liu
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China
| | - Xiaoqun Xu
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China
| | - Jiangning Zeng
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China
- Ocean College of Zhejiang University, Zhoushan, 316000, China
| | - Wei Huang
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China
| | - Xudan Xu
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China
| | - Lu Shou
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China.
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China.
| | - Quanzhen Chen
- Second Institute of Oceanography, Ministry of Natural Resources, No. 36, Baochu North Road, Hangzhou, 310012, China
- Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Hangzhou, 310012, China
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28
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Orr SE, Barnes MC, Joshee L, Uchakina O, McKallip RJ, Bridges CC. Potential mechanisms of cellular injury following exposure to a physiologically relevant species of inorganic mercury. Toxicol Lett 2019; 304:13-20. [PMID: 30630035 DOI: 10.1016/j.toxlet.2019.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 12/19/2018] [Accepted: 01/07/2019] [Indexed: 01/06/2023]
Abstract
Mercury is a toxic metal that is found ubiquitously in the environment. Humans are exposed to different forms of mercury via ingestion, inhalation, and/or dermal absorption. Following exposure, mercuric ions may gain access to target cells and subsequently lead to cellular intoxication. The mechanisms by which mercury accumulation leads to cellular injury and death are not understood fully. Therefore, purpose of this study was to identify the specific intracellular mechanisms that are altered by exposure to inorganic mercury (Hg2+). Normal rat kidney (NRK) cells were exposed to a physiologically relevant form of Hg2+, as a conjugate of cysteine (10 μM or 50 μM). Alterations in oxidative stress were estimated by measuring lipid peroxidation and mitochondrial oxidative stress. Alterations in actin and tubulin were measured using specific fluorescent dyes. Calcium levels were measured using Fluo-3 AM Calcium Indicator while autophagy was identified with Premo™ Autophagy Sensor LC3B-GFP. The current findings show that exposure to Hg2+ leads to enhanced oxidative stress, alterations in cytoskeletal structure, increases in intracellular calcium, and enhanced autophagy. We have established a more complete understanding of intoxication and cellular injury induced by a relevant form of Hg2+ in proximal tubule cells.
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Affiliation(s)
- Sarah E Orr
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, GA, USA.
| | - Mary C Barnes
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, GA, USA.
| | - Lucy Joshee
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, GA, USA.
| | - Olga Uchakina
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, GA, USA.
| | - Robert J McKallip
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, GA, USA.
| | - Christy C Bridges
- Department of Biomedical Sciences, Mercer University School of Medicine, Macon, GA, USA.
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Tokumoto M, Lee JY, Shimada A, Tohyama C, Satoh M. Glutathione has a more important role than metallothionein-I/II against inorganic mercury-induced acute renal toxicity. J Toxicol Sci 2018; 43:275-280. [PMID: 29618716 DOI: 10.2131/jts.43.275] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Inorganic mercury is a harmful heavy metal that causes severe kidney damage. Glutathione (GSH), a tripeptide comprising L-glutamic acid, glycine and L-cysteine, and metallothionein (MT), a cysteine-rich and metal-binding protein, are biologically important protective factors for renal toxicity by inorganic mercury. However, the relationship between GSH and MT for the prevention of renal toxicity by inorganic mercury is unknown. We examined the sensitivity of the mice depleted in GSH by treatment with L-Buthionine-SR-sulfoximine (L-BSO), and MT-I/II null mice genetically deleted for MT-I and MT-II, to inorganic mercury (HgCl2). Kidney damage was not induced in the wild-type mice treated with HgCl2 (30 µmol/kg). In the MT-I/II null mice, renal toxicity was induced by HgCl2 at a dose of 30 µmol/kg but not 1.0 µmol/kg. All GSH-depleted mice of both strains were dead following the injection of HgCl2 (30 µmol/kg). GSH-depleted wild-type mice treated with HgCl2 (1.0 µmol/kg) developed kidney damage similar to MT-I/II null mice treated with HgCl2 (30 µmol/kg). Moreover, renal toxicity induced by HgCl2 (1.0 µmol/kg) was more severe in GSH-depleted MT-I/II null mice compared with GSH-depleted wild-type mice. The present study found that GSH and MT-I/II play cooperatively an important role in the detoxification of severe kidney damage caused by inorganic mercury. In addition, GSH may act as a primary protective factor against inorganic mercury-induced acute renal toxicity, because GSH-depleted mice were more sensitive to inorganic mercury than MT-I/II null mice.
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Affiliation(s)
- Maki Tokumoto
- Laboratory of Pharmaceutical Health Sciences, School of Pharmacy, Aichi Gakuin University
| | - Jin-Yong Lee
- Laboratory of Pharmaceutical Health Sciences, School of Pharmacy, Aichi Gakuin University
| | - Akinori Shimada
- Laboratory of Pathology, Department of Medical Technology, School of Life and Environmental Science, Azabu University
| | - Chiharu Tohyama
- Faculty of Medicine, University of Tsukuba.,National Institute for Environmental Studies.,Program of Environmental Toxicology, School of Public Health, China Medical University
| | - Masahiko Satoh
- Laboratory of Pharmaceutical Health Sciences, School of Pharmacy, Aichi Gakuin University.,National Institute for Environmental Studies
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Pamphlett R, Kum Jew S. Inorganic mercury in human astrocytes, oligodendrocytes, corticomotoneurons and the locus ceruleus: implications for multiple sclerosis, neurodegenerative disorders and gliomas. Biometals 2018; 31:807-819. [PMID: 29959651 PMCID: PMC6133182 DOI: 10.1007/s10534-018-0124-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 06/21/2018] [Indexed: 12/11/2022]
Abstract
Neurotoxic metals have been implicated in the pathogenesis of multiple sclerosis, neurodegenerative disorders and brain tumours but studies of the location of heavy metals in human brains are rare. In a man who injected himself with metallic mercury the cellular location of mercury in his brain was studied after 5 months of continuous exposure to inorganic mercury arising from metallic mercury deposits in his organs. Paraffin sections from the primary motor and sensory cortices and the locus ceruleus in the pons were stained with autometallography to detect inorganic mercury and combined with glial fibrillary acidic protein immunohistochemistry to identify astrocytes. Inorganic mercury was found in grey matter subpial, interlaminar, protoplasmic and varicose astrocytes, white matter fibrous astrocytes, grey but not white matter oligodendrocytes, corticomotoneurons and some locus ceruleus neurons. In summary, inorganic mercury is taken up by five types of human brain astrocytes, as well as by cortical oligodendrocytes, corticomotoneurons and locus ceruleus neurons. Mercury can induce oxidative stress, stimulate autoimmunity and damage DNA, mitochondria and lipid membranes, so its location in these CNS cells suggests it could play a role in the pathogenesis of multiple sclerosis, neurodegenerative conditions such as Alzheimer's disease and amyotrophic lateral sclerosis, and glial tumours.
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Affiliation(s)
- Roger Pamphlett
- Discipline of Pathology, The University of Sydney, Camperdown, Australia. .,Discipline of Pathology, Brain and Mind Centre, The University of Sydney and Department of Neuropathology, Royal Prince Alfred Hospital, 94 Mallett St, Camperdown, NSW, 2050, Australia.
| | - Stephen Kum Jew
- Discipline of Pathology, The University of Sydney, Camperdown, Australia
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Tao R, Shi M, Zou Y, Cheng D, Wang Q, Liu R, Wang A, Zhu J, Deng L, Hu H, Chen X, Du J, Zhu W, Zhao Y, Yang Y. Multicoloured fluorescent indicators for live-cell and in vivo imaging of inorganic mercury dynamics. Free Radic Biol Med 2018; 121:26-37. [PMID: 29684410 DOI: 10.1016/j.freeradbiomed.2018.04.562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 03/21/2018] [Accepted: 04/18/2018] [Indexed: 11/15/2022]
Abstract
Engineered fluorescent indicators for visualizing mercury ion (Hg2+) are powerful tools to illustrate the intracellular distribution and serious toxicity of the ion. However, the sensitive and specific detection of Hg2+ in living cells and in vivo is challenging. This paper reported the development of fluorescent indicators for Hg2+ in green or red color by inserting a circularly permuted fluorescent protein into a highly mercury-specific repressor. These sensors provided a rapid, sensitive, specific, and real-time read-out of Hg2+ dynamics in solutions, bacteria, subcellular organelles of mammalian cells, and zebrafish, thereby providing a useful new method for Hg2+ detection and bioimaging. In conjunction with the hydrogen peroxide sensor HyPer, we found mercury uptake would trigger subcellular oxidative events at the single-cell level, and provided visual evidence of the causality of mercury and oxidative damage. These sensors would paint the landscape of mercury toxicity to cell functions.
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Affiliation(s)
- Rongkun Tao
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Mei Shi
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Yejun Zou
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Di Cheng
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Qiaohui Wang
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Renmei Liu
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Aoxue Wang
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Jiahuan Zhu
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Lei Deng
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Hanyang Hu
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Xianjun Chen
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Jiulin Du
- State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Weiping Zhu
- Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China
| | - Yuzheng Zhao
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China.
| | - Yi Yang
- Synthetic Biology and Biotechnology Laboratory, State Key Laboratory of Bioreactor Engineering, Shanghai Collaborative Innovation Center for Biomanufacturing Technology, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China; State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
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Stoichev T, Tessier E, Almeida CMR, Basto MCP, Vasconcelos VM, Amouroux D. Flux model to estimate the transport of mercury species in a contaminated lagoon (Ria de Aveiro, Portugal). Environ Sci Pollut Res Int 2018; 25:17371-17382. [PMID: 29654462 DOI: 10.1007/s11356-018-1925-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/02/2018] [Indexed: 06/08/2023]
Abstract
The concentrations of dissolved and particulate inorganic mercury (IHg(II)) and methylmercury (MeHg) from the contaminated Laranjo Bay (main freshwater discharge from the Antuã River) were measured by species-specific isotope dilution during six sampling campaigns at high and at low tide. Different effective riverine concentrations were calculated, based on salinity profiles, for specific hydrological conditions. The export fluxes of total Hg and MeHg (324 and 1.24 mol year-1, respectively) from the bay to the rest of the Aveiro Lagoon are much higher than the input fluxes from the Hg source (3.9 and 0.05 mol year-1) and from the Antuã River (10.4 and 0.10 mol year-1). Resuspension of contaminated sediments from Laranjo Bay is crucial for the transport of both IHg(II) and MeHg. Methylation and/or selective enrichment into biogenic particles is responsible for the mobilization of MeHg. Sorption of dissolved IHg(II) onto suspended particles limits its export flux. This is one of the rarest examples where both speciation fluxes and partitioning of mercury are studied in a contaminated coastal environment. Despite the lower fraction of total MeHg (relative to total Hg), the contaminated lagoon may have an impact on coastal areas, particularly if change in the lagoon geometry occurs, due to sea level rise.
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Affiliation(s)
- Teodor Stoichev
- Interdisciplinary Center of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal.
| | - Emmanuel Tessier
- Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux, CNRS/UNIV PAU & PAYS ADOUR, UMR5254, Mira, 64000, Pau, France
| | - Cristina Marisa R Almeida
- Interdisciplinary Center of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal
| | - Maria Clara P Basto
- Interdisciplinary Center of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal
- Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007, Porto, Portugal
| | - Vitor M Vasconcelos
- Interdisciplinary Center of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal
- Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007, Porto, Portugal
| | - David Amouroux
- Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux, CNRS/UNIV PAU & PAYS ADOUR, UMR5254, Mira, 64000, Pau, France
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Faro LRF, Alfonso M, Ferreira VM, Durán R. Role of voltage-gated calcium channels on striatal dopamine release induced by inorganic mercury in freely moving rats. Environ Toxicol Pharmacol 2018; 59:13-16. [PMID: 29482112 DOI: 10.1016/j.etap.2018.02.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 01/29/2018] [Accepted: 02/10/2018] [Indexed: 06/08/2023]
Abstract
The possible role of voltage-sensitive calcium channels (VSCC) activation on the HgCl2-induced dopamine release was investigated using selective VSCC blockers and the dopamine levels were measured by HPLC from samples obtained by in vivo brain microdialysis. Infusion of HgCl2 in nicardipine (10 or 100 μM) or flunaricine (10 μM) pretreated animals had no significant effect on dopamine release induced by HgCl2. Pretreatment with 100 μM flunaricine, 20 μM ω-conotoxin MVIIC, or ω-conotoxin GVIA significantly decreased the HgCl2-induced dopamine release over 61%, 88%, and 99%, respectively. HgCl2-induced dopamine release could be produced, at least in part, by activation of VSCC at dopaminergic terminals, especially N- and P/Q-type.
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Affiliation(s)
| | - Miguel Alfonso
- Department of Functional Biology and Health Sciences, University of Vigo, Spain
| | | | - Rafael Durán
- Department of Functional Biology and Health Sciences, University of Vigo, Spain
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Chan MC, Bautista E, Alvarado-Cruz I, Quintanilla-Vega B, Segovia J. Inorganic mercury prevents the differentiation of SH-SY5Y cells: Amyloid precursor protein, microtubule associated proteins and ROS as potential targets. J Trace Elem Med Biol 2017; 41:119-128. [PMID: 28209268 DOI: 10.1016/j.jtemb.2017.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 01/16/2017] [Accepted: 02/05/2017] [Indexed: 10/20/2022]
Abstract
Exposure to mercury (Hg) occurs through different pathways and forms including methylmecury (MeHg) from seafood and rice, ethylmercury (EtHg), and elemental Hg (Hg0) from dental amalgams and artisanal gold mining. Once in the brain all these forms are transformed to inorganic Hg (I-Hg), where it bioaccumulates and remains for long periods. Hg is a well-known neurotoxicant, with its most damaging effects reported during brain development, when cellular key events, such as cell differentiation take place. A considerable number of studies report an impairment of neuronal differentiation due to MeHg exposure, however the effects of I-Hg, an important form of Hg found in brain, have received less attention. In this study, we decided to examine the effects of I-Hg exposure (5, 10 and 20μM) on the differentiation of SH-SY5Y cells induced by retinoic acid (RA, 10μM). We observed extension of neuritic processes and increased expression of neuronal markers (MAP2, tubulin-βIII, and Tau) after RA stimulation, all these effects were decreased by the co-exposure to I-Hg. Interestingly, I-Hg increased the levels of reactive oxygen species (ROS) and nitric oxide (NO) accompanied with increased levels of inducible nitric oxide synthase (iNOS) and, dimethylarginine dimethylaminohydrolase 1 (DDHA1). Remarkably I-Hg decreased levels of nitric oxide synthase neuronal (nNOS). Moreover I-Hg reduced the levels of tyrosine hydroxylase (TH) and amyloid precursor protein (APP) a protein recently involved in neuronal differentiation. These data suggest that the exposure to I-Hg impairs cell differentiation, and point to new potential targets of Hg toxicity such as APP and NO signaling.
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Affiliation(s)
- Miguel Chin Chan
- Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico; Facultad de Ciencias Químico Biológicas, Universidad Autónoma de Campeche, Campeche 4039, Mexico
| | - Elizabeth Bautista
- Departmento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico; Facultad de Ciencias de la Salud, Universidad Anáhuac Norte, 52786, Huixquilucan, Mexico
| | - Isabel Alvarado-Cruz
- Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico
| | - Betzabet Quintanilla-Vega
- Departmento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico
| | - José Segovia
- Departmento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, 07360, Mexico.
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Xu X, Meng B, Zhang C, Feng X, Gu C, Guo J, Bishop K, Xu Z, Zhang S, Qiu G. The local impact of a coal-fired power plant on inorganic mercury and methyl-mercury distribution in rice (Oryza sativa L.). Environ Pollut 2017; 223:11-18. [PMID: 28139322 DOI: 10.1016/j.envpol.2016.11.042] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 10/15/2016] [Accepted: 11/14/2016] [Indexed: 06/06/2023]
Abstract
Emission from coal-fired power plants is one of the major anthropogenic sources of mercury (Hg) in the environment, because emitted Hg can be quickly deposited nearby the source, attention is paid to the effects of coal-burning facilities on levels of toxic methyl-mercury (MeHg) in biota near such sources. Since rice is an agricultural crop that can bio-accumulate MeHg, the potential effects of a large Hg-emitting coal-fired power plant in Hunan Province, China on both inorganic Hg (Hg(II)) and MeHg distributions in rice was investigated. Relatively high MeHg (up to 3.8 μg kg-1) and Hg(II) (up to 22 μg kg-1) concentrations were observed in rice samples collected adjacent to the plant, suggesting a potential impact of Hg emission from the coal fired power plant on the accumulation of Hg in rice in the area. Concentrations of MeHg in rice were positively correlated with soil MeHg, soil S, and gaseous elemental Hg (GEM) in ambient air. Soil MeHg was the most important factor controlling MeHg concentrations in rice. The methylation of Hg in soils may be controlled by factors such as the chemical speciation of inorganic Hg, soil S, and ambient GEM.
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Affiliation(s)
- Xiaohang Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bo Meng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Chao Zhang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Chunhao Gu
- Department of Ecosystems Science and Management, University of Wyming, 82071, United States
| | - Jianyang Guo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Kevin Bishop
- Department of Earth Sciences, University of Uppsala, Uppsala, Sweden; Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Zhidong Xu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Sensen Zhang
- School of Geosciences and Info-Physics, Central South University, CAS, Changsha, 410000, China
| | - Guangle Qiu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
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Tang W, Dang F, Evans D, Zhong H, Xiao L. Understanding reduced inorganic mercury accumulation in rice following selenium application: Selenium application routes, speciation and doses. Chemosphere 2017; 169:369-376. [PMID: 27886539 DOI: 10.1016/j.chemosphere.2016.11.087] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 11/04/2016] [Accepted: 11/15/2016] [Indexed: 05/09/2023]
Abstract
Selenium (Se) has recently been demonstrated to reduce inorganic mercury (IHg) accumulation in rice plants, while its mechanism is far from clear. Here, we aimed at exploring the potential effects of Se application routes (soil or foliar application with Se), speciation (selenite and selenate), and doses on IHg-Se antagonistic interactions in soil-rice systems. Results of our pot experiments indicated that soil application but not foliar application could evidently reduce tissue IHg concentrations (root: 0-48%, straw: 15-58%, and brown rice: 26-74%), although both application routes resulted in comparable Se accumulation in aboveground tissues. Meanwhile, IHg distribution in root generally increased with amended Se doses in soil, suggesting antagonistic interactions between IHg and Se in root. These results provided initial evidence that IHg-Se interactions in the rhizosphere (i.e., soil or rice root), instead of those in the aboveground tissues, could probably be more responsible for the reduced IHg bioaccumulation following Se application. Furthermore, Se dose rather than Se speciation was found to be more important in controlling IHg accumulation in rice. Our findings regarding the importance of IHg-Se interactions in the rhizosphere, together with the systematic investigation of key factors affecting IHg-Se antagonism and IHg bioaccumulation, advance our understanding of Hg dynamics in soil-rice systems.
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Affiliation(s)
- Wenli Tang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
| | - Fei Dang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, PR China.
| | - Douglas Evans
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China; Environmental and Resource Studies Program (ERS), Trent University, Peterborough, Ontario, Canada.
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China; Environmental and Life Sciences Program (EnLS), Trent University, Peterborough, Ontario, Canada.
| | - Lin Xiao
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
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Lohren H, Bornhorst J, Fitkau R, Pohl G, Galla HJ, Schwerdtle T. Effects on and transfer across the blood-brain barrier in vitro-Comparison of organic and inorganic mercury species. BMC Pharmacol Toxicol 2016; 17:63. [PMID: 27978854 PMCID: PMC5159962 DOI: 10.1186/s40360-016-0106-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 11/19/2016] [Indexed: 01/22/2023] Open
Abstract
Background Transport of methylmercury (MeHg) across the blood-brain barrier towards the brain side is well discussed in literature, while ethylmercury (EtHg) and inorganic mercury are not adequately characterized regarding their entry into the brain. Studies investigating a possible efflux out of the brain are not described to our knowledge. Methods This study compares, for the first time, effects of organic methylmercury chloride (MeHgCl), EtHg-containing thiomersal and inorganic Hg chloride (HgCl2) on as well as their transfer across a primary porcine in vitro model of the blood-brain barrier. Results With respect to the barrier integrity, the barrier model exhibited a much higher sensitivity towards HgCl2 following basolateral incubation (brain-facing side) as compared to apical application (blood-facing side). These HgCl2 induced effects on the barrier integrity after brain side incubation are comparable to that of the organic species, although MeHgCl and thiomersal exerted much higher cytotoxic effects in the barrier building cells. Hg transfer rates following exposure to organic species in both directions argue for diffusion as transfer mechanism. Inorganic Hg application surprisingly resulted in a Hg transfer out of the brain-facing compartment. Conclusions In case of MeHgCl and thiomersal incubation, mercury crossed the barrier in both directions, with a slight accumulation in the basolateral, brain-facing compartment, after simultaneous incubation in both compartments. For HgCl2, our data provide first evidence that the blood-brain barrier transfers mercury out of the brain.
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Affiliation(s)
- Hanna Lohren
- Department of Food Chemistry, Institute of Nutritional Science, Univeristy of Potsdam, Potsdam, Germany
| | - Julia Bornhorst
- Department of Food Chemistry, Institute of Nutritional Science, Univeristy of Potsdam, Potsdam, Germany
| | - Romy Fitkau
- Department of Food Chemistry, Institute of Nutritional Science, Univeristy of Potsdam, Potsdam, Germany
| | - Gabriele Pohl
- Department of Food Chemistry, Institute of Nutritional Science, Univeristy of Potsdam, Potsdam, Germany
| | | | - Tanja Schwerdtle
- Department of Food Chemistry, Institute of Nutritional Science, Univeristy of Potsdam, Potsdam, Germany.
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Zeng L, Zheng JL, Wang YH, Xu MY, Zhu AY, Wu CW. The role of Nrf2/Keap1 signaling in inorganic mercury induced oxidative stress in the liver of large yellow croaker Pseudosciaena crocea. Ecotoxicol Environ Saf 2016; 132:345-352. [PMID: 27362492 DOI: 10.1016/j.ecoenv.2016.05.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 05/04/2016] [Accepted: 05/05/2016] [Indexed: 06/06/2023]
Abstract
The aim of the present study was to evaluate the effects of acute inorganic Hg exposure (0, 32 and 64μgHgL(-1)) on lipid peroxidation, activities and gene expression of antioxidant enzymes (Cu/Zn-SOD, CAT, GPx, GR and GST), and mRNA levels of the Keap1-Nrf2 signaling molecules at different exposure times (6h, 12h, 24h, 48h, and 96h) in the liver of large yellow croaker Pseudosciaena crocea. The results showed that lipid peroxidation was sharply reduced by 32μg Hg L(-1) during 6-12h before returning to control levels. Similarly, lipid peroxidation was significantly reduced during 6-12h followed by a sharp increase towards the end of the exposure in the 64μgHgL(-1) group. There was a negative relationship between lipid peroxidation and antioxidant enzyme activities, and positive relationship between activities and gene expression of antioxidant enzymes, suggesting that the changes at a molecular level may underlie enzymatic level and accordingly affect hepatic lipid peroxidation. Obtained results also showed a coordinated transcriptional regulation of antioxidant genes, suggesting that Nrf2 is required for the protracted induction of these genes. Furthermore, a negative relationship between the mRNA levels of Nrf2 and Keap1 indicated that Keap1 may play an important role in switching off the Nrf2 response. In conclusion, this is the first study to elucidate effects of waterborne Hg on antioxidant system in large yellow croaker through the Keap1-Nrf2 pathway, which will aid our understanding of the molecular mechanisms of waterborne heavy metal on antioxidant responses in fish.
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Affiliation(s)
- Lin Zeng
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China
| | - Jia-Lang Zheng
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China
| | - Yong-Hong Wang
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China
| | - Mei-Ying Xu
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China
| | - Ai-Yi Zhu
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China
| | - Chang-Wen Wu
- National Engineering Research Center of Marine Facilities Aquaculture, Zhejiang Ocean University, Zhoushan 316022, PR China.
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Crowe W, Allsopp PJ, Watson GE, Magee PJ, Strain JJ, Armstrong DJ, Ball E, McSorley EM. Mercury as an environmental stimulus in the development of autoimmunity - A systematic review. Autoimmun Rev 2016; 16:72-80. [PMID: 27666813 DOI: 10.1016/j.autrev.2016.09.020] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 08/13/2016] [Indexed: 12/24/2022]
Abstract
Autoimmune diseases result from an interplay of genetic predisposition and factors which stimulate the onset of disease. Mercury (Hg), a well-established toxicant, is an environmental factor reported to be linked with autoimmunity. Hg exists in several chemical forms and is encountered by humans in dental amalgams, certain vaccines, occupational exposure, atmospheric pollution and seafood. Several studies have investigated the effect of the various forms of Hg, including elemental (Hg0), inorganic (iHg) and organic mercury (oHg) and their association with autoimmunity. In vitro studies using peripheral blood mononuclear cells (PBMC) from healthy participants have shown that methylmercury (MeHg) causes cell death at lower concentrations than iHg albeit exposure to iHg results in a more enhanced pro-inflammatory profile in comparison to MeHg. In vivo research utilising murine models susceptible to the development of metal-induced autoimmunity report that exposure to iHg results in a lupus-like syndrome, whilst mice exposed to MeHg develop autoimmunity without the formation of immune complexes. Furthermore, lower concentrations of IgE are detected in MeHg-treated animals in comparison with those treated with iHg. It appears that, oHg has a negative impact on animal models with existing autoimmunity. The research conducted on humans in this area is diverse in study design and the results are conflicting. There is currently no evidence to implicate a role for Hg0 exposure from dental amalgams in the development or perpetuation of autoimmune disease, apart from some suggestion of individual sensitivity. Several studies have consistently shown a positive correlation between iHg exposure and serum autoantibody concentrations in gold miners, although the clinical impact of iHg remains unknown. Furthermore, a limited number of studies have reported individuals with autoimmune disease have higher concentrations of blood Hg compared to healthy controls. In summary, it appears that iHg perpetuates markers of autoimmunity to a greater extent than oHg, albeit the impact on clinical outcomes in humans is yet to be elucidated.
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Affiliation(s)
- William Crowe
- Northern Ireland Centre for Food and Health (NICHE), Ulster University, BT52 1SA, Northern, Ireland.
| | - Philip J Allsopp
- Northern Ireland Centre for Food and Health (NICHE), Ulster University, BT52 1SA, Northern, Ireland.
| | - Gene E Watson
- Eastman Institute for Oral Health and Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, United States.
| | - Pamela J Magee
- Northern Ireland Centre for Food and Health (NICHE), Ulster University, BT52 1SA, Northern, Ireland.
| | - J J Strain
- Northern Ireland Centre for Food and Health (NICHE), Ulster University, BT52 1SA, Northern, Ireland.
| | - David J Armstrong
- Department of Rheumatology, Altnagelvin Area Hospital, Glenshane Road, Londonderry BT47 6SB, Northern, Ireland.
| | - Elizabeth Ball
- Department of Rheumatology, Musgrave Park Hospital, Stockman's Lane, Belfast, BT9 7JB, Northern, Ireland.
| | - Emeir M McSorley
- Northern Ireland Centre for Food and Health (NICHE), Ulster University, BT52 1SA, Northern, Ireland.
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40
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Bridges CC, Zalups RK. Mechanisms involved in the transport of mercuric ions in target tissues. Arch Toxicol 2017; 91:63-81. [PMID: 27422290 DOI: 10.1007/s00204-016-1803-y] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 07/07/2016] [Indexed: 01/16/2023]
Abstract
Mercury exists in the environment in various forms, all of which pose a risk to human health. Despite guidelines regulating the industrial release of mercury into the environment, humans continue to be exposed regularly to various forms of this metal via inhalation or ingestion. Following exposure, mercuric ions are taken up by and accumulate in numerous organs, including brain, intestine, kidney, liver, and placenta. In order to understand the toxicological effects of exposure to mercury, a thorough understanding of the mechanisms that facilitate entry of mercuric ions into target cells must first be obtained. A number of mechanisms for the transport of mercuric ions into target cells and organs have been proposed in recent years. However, the ability of these mechanisms to transport mercuric ions and the regulatory features of these carriers have not been characterized completely. The purpose of this review is to summarize the current findings related to the mechanisms that may be involved in the transport of inorganic and organic forms of mercury in target tissues and organs. This review will describe mechanisms known to be involved in the transport of mercury and will also propose additional mechanisms that may potentially be involved in the transport of mercuric ions into target cells.
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41
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Xu X, Zhao J, Li Y, Fan Y, Zhu N, Gao Y, Li B, Liu H, Li YF. Demethylation of methylmercury in growing rice plants: An evidence of self-detoxification. Environ Pollut 2016; 210:113-120. [PMID: 26708765 DOI: 10.1016/j.envpol.2015.12.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 12/08/2015] [Accepted: 12/08/2015] [Indexed: 06/05/2023]
Abstract
Mercury (Hg) is a global pollutant that poses a serious threat to human and the environment. Rice was found as an important source for human exposure to Hg in some areas. In this study, the transportation and transformation of IHg and MeHg in rice plants exposed to IHg or MeHg were investigated. The IHg and MeHg concentrations in rice roots and shoots collected every five days were analyzed by HPLC-ICP-MS and SR-XANES. When exposed to MeHg, the percent of IHg in rice roots and shoots increased while MeHg decreased significantly, suggesting prominent demethylation of MeHg occurred. However no notable MeHg was found in both roots and shoots of rice plant when exposed to IHg. SR-XANES analysis further confirmed the demethylation of MeHg with rice. This study provides a new finding that demethylation of MeHg could occur in growing rice, which may be a self-defense process of rice plant.
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Affiliation(s)
- Xiaohan Xu
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, and Laboratory of Metallomics and Nanometallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiating Zhao
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, and Laboratory of Metallomics and Nanometallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Yunyun Li
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, and Laboratory of Metallomics and Nanometallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuqin Fan
- Shandong Maternity and Child Care Hospital, Jinan 250001, China
| | - Nali Zhu
- Laboratory of Proteomics, Protein Science Core Facility Center, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yuxi Gao
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, and Laboratory of Metallomics and Nanometallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Bai Li
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, and Laboratory of Metallomics and Nanometallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Hanyu Liu
- Beijing National Day School, Beijing 100049, China
| | - Yu-Feng Li
- State Environmental Protection Engineering Center for Mercury Pollution Prevention and Control, and Laboratory of Metallomics and Nanometallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
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Pereira P, Puga S, Cardoso V, Pinto-Ribeiro F, Raimundo J, Barata M, Pousão-Ferreira P, Pacheco M, Almeida A. Inorganic mercury accumulation in brain following waterborne exposure elicits a deficit on the number of brain cells and impairs swimming behavior in fish (white seabream-Diplodus sargus). Aquat Toxicol 2016; 170:400-412. [PMID: 26688460 DOI: 10.1016/j.aquatox.2015.11.031] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 11/30/2015] [Accepted: 11/30/2015] [Indexed: 06/05/2023]
Abstract
The current study contributes to fill the knowledge gap on the neurotoxicity of inorganic mercury (iHg) in fish through the implementation of a combined evaluation of brain morphometric alterations (volume and total number of neurons plus glial cells in specific regions of the brain) and swimming behavior (endpoints related with the motor activity and mood/anxiety-like status). White seabream (Diplodus sargus) was exposed to realistic levels of iHg in water (2μgL(-1)) during 7 (E7) and 14 days (E14). After that, fish were allowed to recover for 28 days (PE28) in order to evaluate brain regeneration and reversibility of behavioral syndromes. A significant reduction in the number of cells in hypothalamus, optic tectum and cerebellum was found at E7, accompanied by relevant changes on swimming behavior. Moreover, the decrease in the number of neurons and glia in the molecular layer of the cerebellum was followed by a contraction of its volume. This is the first time that a deficit on the number of cells is reported in fish brain after iHg exposure. Interestingly, a recovery of hypothalamus and cerebellum occurred at E14, as evidenced by the identical number of cells found in exposed and control fish, and volume of cerebellum, which might be associated with an adaptive phenomenon. After 28 days post-exposure, the optic tectum continued to show a decrease in the number of cells, pointing out a higher vulnerability of this region. These morphometric alterations coincided with numerous changes on swimming behavior, related both with fish motor function and mood/anxiety-like status. Overall, current data pointed out the iHg potential to induce brain morphometric alterations, emphasizing a long-lasting neurobehavioral hazard.
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Affiliation(s)
- Patrícia Pereira
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Sónia Puga
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Vera Cardoso
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Filipa Pinto-Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Joana Raimundo
- IPMA-Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal
| | - Marisa Barata
- IPMA-Aquaculture Research Station, 8700-005 Olhão, Portugal
| | | | - Mário Pacheco
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Armando Almeida
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences (ECS), Campus of Gualtar, University of Minho, 4750-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal
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43
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Xu X, Wang WX. Isotopic fractionation during the uptake and elimination of inorganic mercury by a marine fish. Environ Pollut 2015; 206:202-8. [PMID: 26184584 DOI: 10.1016/j.envpol.2015.07.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 07/01/2015] [Accepted: 07/03/2015] [Indexed: 05/12/2023]
Abstract
This study investigated the mass dependent (MDF) and independent fractionation (MIF) of stable mercury isotopes in fish during the uptake and elimination of inorganic species. Mercury accumulation during the exposure led to re-equilibration of organ isotopic compositions with the external sources, and elimination terminated the equilibrating with isotope ratios moving back to the original values. Generally, the isotopic behaviors corresponded to the changes of Hg accumulation in the muscle and liver, causing by the internal transportation, organ redistribution, and mixing of different sources. A small degree of MDF caused by biotransformation of Hg in the liver was documented during the elimination, whereas MIF was not observed. The absence of MIF during geochemical and metabolic processes suggested that mercury isotopes can be used as source tracers. Additionally, fish liver is a more responsive organ than muscle to track Hg source when it is mainly composed of inorganic species.
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Affiliation(s)
- Xiaoyu Xu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Wen-Xiong Wang
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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44
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Li P, Du B, Chan HM, Feng X. Human inorganic mercury exposure, renal effects and possible pathways in Wanshan mercury mining area, China. Environ Res 2015; 140:198-204. [PMID: 25863593 DOI: 10.1016/j.envres.2015.03.033] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/26/2015] [Accepted: 03/29/2015] [Indexed: 06/04/2023]
Abstract
Rice can accumulate methylmercury (MeHg) and rice consumption is the main route of MeHg exposure for the local population in Guizhou, China. However, inorganic Hg (IHg) load in human body is not comprehensively studied in highly Hg polluted areas such as Hg mining areas. This study is designed to evaluate human IHg exposure, related renal effects and possible pathways in Wanshan Hg mining area, Guizhou, Southwest China. Residents lived within 3 km to the mine waste heaps showed high Urine Hg (UHg) concentrations and the geometrical means (Geomean) of UHg were 8.29, 5.13, and 10.3 μg/g Creatinine (Cr) at site A, D, and E, respectively. It demonstrated a gradient of UHg concentrations with the distance from the pollution sources. A significantly positive correlation between paired results for UHg concentrations and serum creatinine (SCr) was observed in this study, but not for UHg and blood urea nitrogen (BUN). There are significant increases of SCr in two quartiles with high UHg concentrations. The results indicated that human IHg exposure may cause impairment of renal function. By calculation of Probable Daily Intake from different routes, we found that dietary intake is the main pathway of IHg exposure for the local population, rather than inhalation of Hg vapor.
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Affiliation(s)
- Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China
| | - Buyun Du
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hing Man Chan
- Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Canada K1N 6N5
| | - Xinbin Feng
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
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45
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Mailloux RJ, Yumvihoze E, Chan HM. Superoxide anion radical (O2(-)) degrades methylmercury to inorganic mercury in human astrocytoma cell line (CCF-STTG1). Chem Biol Interact 2015; 239:46-55. [PMID: 26111762 DOI: 10.1016/j.cbi.2015.06.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 06/11/2015] [Accepted: 06/19/2015] [Indexed: 10/23/2022]
Abstract
Methylmercury (MeHg) is a global pollutant that is affecting the health of millions of people worldwide. However, the mechanism of MeHg toxicity still remains somewhat elusive and there is no treatment. It has been known for some time that MeHg can be progressively converted to inorganic mercury (iHg) in various tissues including the brain. Recent work has suggested that cleavage of the carbon-metal bond in MeHg in a biological environment is facilitated by reactive oxygen species (ROS). However, the oxyradical species that actually mediates this process has not been identified. Here, we provide evidence that superoxide anion radical (O2(-)) can convert MeHg to iHg. The calculated second-order rate constant for the degradation of 1μM MeHg by O2(-) generated by xanthine/xanthine oxidase was calculated to be 2×10(5)M(-1)s(-1). We were also able to show that this bioconversion can proceed in intact CCF-STTG1 human astrocytoma cells exposed to paraquat (PQ), a O2(-) generating viologen. Notably, exposure of cells to increasing amounts of PQ led to a dose dependent increase in both MeHg and iHg. Indeed, a 24h exposure to 500μM PQ induced a ∼13-fold and ∼18-fold increase in intracellular MeHg and iHg respectively. These effects were inhibited by superoxide dismutase mimetic MnTBAP. In addition, we also observed that a 24h exposure to a biologically relevant concentration of MeHg (1μM) did not induce cell death, oxidative stress, or even changes in cellular O2(-) and H2O2. However, co-exposure to PQ enhanced MeHg toxicity which was associated with a robust increase in cell death and oxidative stress. Collectively our results show that O2(-) can bioconvert MeHg to iHg in vitro and in intact cells exposed to conditions that simulate high intracellular O2(-) production. In addition, we show for the first time that O2(-) mediated degradation of MeHg to iHg enhances the toxicity of MeHg by facilitating an accumulation of both MeHg and iHg in the intracellular environment.
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Affiliation(s)
- Ryan J Mailloux
- University of Ottawa, Department of Biology, Center for Advanced Research in Environmental Genomics, Ottawa, ON K1N 6N5, Canada
| | - Emmanuel Yumvihoze
- University of Ottawa, Department of Biology, Center for Advanced Research in Environmental Genomics, Ottawa, ON K1N 6N5, Canada
| | - Hing Man Chan
- University of Ottawa, Department of Biology, Center for Advanced Research in Environmental Genomics, Ottawa, ON K1N 6N5, Canada.
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Iwai-Shimada M, Satoh H, Nakai K, Tatsuta N, Murata K, Akagi H. Methylmercury in the breast milk of Japanese mothers and lactational exposure of their infants. Chemosphere 2015; 126:67-72. [PMID: 25723533 DOI: 10.1016/j.chemosphere.2014.12.086] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 12/15/2014] [Accepted: 12/26/2014] [Indexed: 06/04/2023]
Abstract
The human fetus is known to be exposed to methylmercury (MeHg), but little is known about the risk of infant exposure via breast milk. To evaluate the lactational exposure to MeHg via breast milk in Japanese infants, the levels of total mercury (THg) and MeHg were determined in breast milk and maternal blood using samples from a birth cohort study at the Tohoku Study of Child Development. Maternal blood and breast milk were collected one day postpartum and one month after delivery, respectively. The median THg (and MeHg) concentrations in maternal RBCs, plasma and breast milk were 17.8 ng g(-1) (17.8 ng g(-1)), 1.51 ng g(-1) (1.33 ng g(-1)) and 0.81 ng g(-1) (0.45 ng g(-1)), respectively (n=27). The median percentage of MeHg in THg was 54% in breast milk. Breast milk contained substantial amounts of MeHg, which was strongly associated with the internal accumulation of MeHg and the lipid content of the milk (r=0.684). The range of lipid contents in milk varied widely from 0.50 to 6.60 g/100 g of milk, with a median of 3.60 g/100 g. The median (range) weekly average intake of MeHg via breast milk was estimated to be 0.63 μg kg(-1) (0.08-1.68 μg kg(-1)) BW/week. Because the MeHg and lipid contents in milk substantially fluctuate, an investigation of the variations of MeHg and lipid content in breast milk may be required for a more precise risk assessment.
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Affiliation(s)
- Miyuki Iwai-Shimada
- Environmental Health Sciences, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan; Research Fellow of the Japan Society for the Promotion of Science, Chiyoda-ku, Tokyo, Japan.
| | - Hiroshi Satoh
- Environmental Health Sciences, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Kunihiko Nakai
- Department of Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Nozomi Tatsuta
- Department of Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Katsuyuki Murata
- Environmental Health Sciences, Akita University Graduate School of Medicine, Akita, Japan
| | - Hirokatsu Akagi
- International Mercury Laboratory Inc., Minamata, Kumamoto, Japan
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47
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Wang Y, Wang D, Lin L, Wang M. Quantitative proteomic analysis reveals proteins involved in the neurotoxicity of marine medaka Oryzias melastigma chronically exposed to inorganic mercury. Chemosphere 2015; 119:1126-1133. [PMID: 25460752 DOI: 10.1016/j.chemosphere.2014.09.053] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 09/11/2014] [Accepted: 09/18/2014] [Indexed: 06/04/2023]
Abstract
Mercury is a ubiquitous environmental contaminant which exerts neurotoxicity upon animals. Nevertheless, the molecular mechanisms involved in inorganic mercury neurotoxicity are unknown. We investigated protein profiles of marine medaka, chronically exposed to mercuric chloride using two-dimensional difference gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-TOF MS) analysis. The mercury accumulation and ultrastructure were also examined in the brain. The results showed that mercury was significantly accumulated in the treated brain, and subsequently caused a noticeable damage. The comparison of 2D-DIGE protein profiles between the control and treatment revealed that 16 protein spots were remarkably altered in abundance, which were further submitted for MALDI-TOF-TOF MS analysis. The identified proteins indicated that inorganic mercury may cause neurotoxicity through the induction of oxidative stress, cytoskeletal assembly dysfunction and metabolic disorders. Thus, this study provided a basis for a better understanding of the molecular mechanisms involved in mercury neurotoxicity.
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Affiliation(s)
- Yuyu Wang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361005, China; Center for Environmental Health Research, South China Institute of Environmental Sciences, Ministry of Environmental Protection of the People's Republic of China, Guangzhou 510655, China
| | - Dazhi Wang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Lin Lin
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Minghua Wang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen 361005, China.
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48
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Vázquez M, Devesa V, Vélez D. Characterization of the intestinal absorption of inorganic mercury in Caco-2 cells. Toxicol In Vitro 2014; 29:93-102. [PMID: 25283090 DOI: 10.1016/j.tiv.2014.09.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 09/16/2014] [Accepted: 09/23/2014] [Indexed: 11/16/2022]
Abstract
The main form of mercury exposure in the general population is through food. Intestinal absorption is therefore a key step in the penetration of mercury into the systemic circulation, and should be considered when evaluating exposure risk. Many studies have investigated the transport of mercury species in different cell lines, though the mechanisms underlying their intestinal absorption are not clear. This study evaluates the accumulation and transport of Hg(II), one of the mercury species ingested in food, using Caco-2 cells as intestinal epithelium model with the purpose of clarifying the mechanisms involved in its absorption. Hg(II) shows moderate absorption, and its transport fundamentally takes place via a carrier-mediated transcellular mechanism. The experiments indicate the participation of an energy-dependent transport mechanism. In addition, H(+)- and Na(+)-dependent transport is also observed. These data, together with those obtained from inhibition studies using specific substrates or inhibitors of different transporter families, suggest the participation of divalent cation and amino acid transporters, and even some organic anion transporters, in Hg(II) intestinal transport. An important cellular accumulation of up to 51% is observed - a situation which in view of the toxic nature of this species could affect intestinal mucosal function. This study contributes new information on the mechanisms of transport of Hg(II) at intestinal level, and which may be responsible for penetration of this mercurial form into the systemic circulation.
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Affiliation(s)
- M Vázquez
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Avenida Agustín Escardino 7, 46980 Paterna, Valencia, Spain
| | - V Devesa
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Avenida Agustín Escardino 7, 46980 Paterna, Valencia, Spain
| | - D Vélez
- Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Avenida Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
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49
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Pereira P, Raimundo J, Araújo O, Canário J, Almeida A, Pacheco M. Fish eyes and brain as primary targets for mercury accumulation - a new insight on environmental risk assessment. Sci Total Environ 2014; 494-495:290-298. [PMID: 25058895 DOI: 10.1016/j.scitotenv.2014.07.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 07/02/2014] [Accepted: 07/03/2014] [Indexed: 06/03/2023]
Abstract
Fish eyes and brain are highly susceptible to environmental Hg exposure but this issue is still scarcely investigated, mainly regarding methylmercury (MeHg) accumulation. Yet, Hg levels in fish lens have not been previously examined under field conditions. Total Hg (tHg), MeHg and inorganic Hg (iHg) levels were assessed in the brain, eye wall and lens of the golden grey mullet (Liza aurata) from an Hg contaminated area, both in winter and summer, together with water and sediment levels. Sampling was performed at Aveiro lagoon (Portugal) where a confined area (LAR) is severely contaminated by Hg. Fish brain, eye wall and lens accumulated higher levels of tHg, MeHg and iHg at LAR than the reference site, reflecting faithfully environmental spatial differences. The brain and eye wall responded also to the winter-summer changes found in water and sediment, accumulating higher levels of MeHg (and tHg) in winter. Contrarily, lens was unable to reflect seasonal changes, probably due to its composition and structural stability over time. The three neurosensory structures accumulated preferentially MeHg than iHg (MeHg was higher than 77% of tHg). Lens exhibited a higher retention capacity of MeHg (mean around 1 μg g(-1) at LAR), accumulating higher levels than the other two tissues. Interestingly, MeHg and iHg levels were significantly correlated for the brain and eye wall but poorly associated within the two analysed eye components. The high levels of MeHg found in the brain, eye wall and lens could compromise their functions and this needs further research.
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Affiliation(s)
- Patrícia Pereira
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal; IPMA - Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal; Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; ICVS/3Bs, PT Government Associated Laboratory, Braga/Guimarães, Portugal.
| | - Joana Raimundo
- IPMA - Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal; Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), University of Porto, 4050-123 Porto, Portugal
| | - Olinda Araújo
- IPMA - Portuguese Institute for the Sea and Atmosphere, Av. Brasília, 1449-006 Lisbon, Portugal
| | - João Canário
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Armando Almeida
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; ICVS/3Bs, PT Government Associated Laboratory, Braga/Guimarães, Portugal
| | - Mário Pacheco
- Department of Biology and CESAM, University of Aveiro, 3810-193 Aveiro, Portugal
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50
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Small JM, Hintelmann H. Sulfide and mercury species profiles in two Ontario boreal shield lakes. Chemosphere 2014; 111:96-102. [PMID: 24997905 DOI: 10.1016/j.chemosphere.2014.03.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 02/13/2014] [Accepted: 03/01/2014] [Indexed: 06/03/2023]
Abstract
The cycling of sulfur in freshwater environments plays an important role in the cycling of metals. In this study, acid volatile sulfides were measured at nanomolar levels using a purge-and-trap preconcentration, followed by methylene blue derivatization with HPLC separation and UV-Vis detection. The limit of detection using the preconcentration step was 7.5ngL(-1) or 0.23nM sulfide. Profiles of sulfide and methylmercury were generated for two Ontario lakes. Sulfide concentrations were inversely related to dissolved oxygen concentrations and significant levels of anoxia had developed in both lakes. In both Plastic Lake and Lake 658, mercury concentrations also increased below the oxycline. Lake 658 showed a strong positive correlation between sulfide and methylmercury (CMeHg=2×10(-6)⋅Csulfide+0.198; r=0.96, p=1.2×10(-5)), at the time of sampling.
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Affiliation(s)
- Jeff M Small
- Trent University, Department of Chemistry, 1600 West Bank Dr., Peterborough, ON K9J 7B8, Canada.
| | - Holger Hintelmann
- Trent University, Department of Chemistry, 1600 West Bank Dr., Peterborough, ON K9J 7B8, Canada.
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