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Nakamura M, Tatsuta N, Murata K, Nakai K, Iwata T, Otobe T, Sakamoto M, Yamamoto M, Itatani M, Miura Y, Koriyama C. Neurodevelopmental associations of prenatal and postnatal methylmercury exposure among first-grade children in the Kinan region, Japan. ENVIRONMENTAL RESEARCH 2023; 235:116688. [PMID: 37467938 DOI: 10.1016/j.envres.2023.116688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 07/14/2023] [Accepted: 07/15/2023] [Indexed: 07/21/2023]
Abstract
The most severe effects of methylmercury (MeHg) exposure during child development are thought to result from exposure during fetal life and childhood. However, comparing the neurodevelopmental effects of prenatal and postnatal MeHg exposure (PreMeHg and PostMeHg, respectively) remains unclear. We aimed to investigate the associations between neurodevelopmental indicators and PreMeHg or PostMeHg. The participants were 134 children in the first grade of elementary schools aged 7-8 years from the Kinan region, an area with high consumption of MeHg-rich whales and tunas in Japan. We measured MeHg levels in preserved umbilical cord tissues and total mercury (T-Hg) levels in children's hair to estimate PreMeHg and PostMeHg levels, respectively. Neuropsychological (intelligence quotient testing and Boston Naming Test) and neurophysiological (brainstem auditory evoked potential [BAEP], visual evoked potential [VEP], and color vision tests) studies were performed to evaluate the neurodevelopmental status. Multiple regression analyses were conducted according to sex. The geometric mean MeHg levels in preserved umbilical cord tissues and T-Hg levels in children's hair were 0.11 μg/g and 2.94 μg/g, respectively. Neither PreMeHg nor PostMeHg was related to neuropsychological indicators. Some associations between MeHg exposure and neurophysiological results were observed only in boys. N145 latency in VEPs was significantly prolonged with increasing PreMeHg (β: 12.01, 95% confidence interval [CI]: 0.648, 23.38). The III-V interpeak intervals in BAEP were significantly prolonged with increasing PreMeHg or PostMeHg (β [95% CI]: 0.142 [0.041, 0.243] and 0.159 [0.052, 0.265], respectively). After adjusting for PreMeHg, the association between PostMeHg and BAEP latencies disappeared. In conclusion, the latency in the auditory and visual pathways was significantly prolonged with increasing PreMeHg in boys. These findings suggest that male fetuses may be more susceptible to MeHg exposure.
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Affiliation(s)
- Masaaki Nakamura
- Department of Clinical Medicine, National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan.
| | - Nozomi Tatsuta
- Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai City, Miyagi, 980-8575, Japan.
| | - Katsuyuki Murata
- Department of Environmental Health Sciences, Akita University Graduate School of Medicine, 1-1 Hondo, Akita City, Akita, 010-8543, Japan.
| | - Kunihiko Nakai
- Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai City, Miyagi, 980-8575, Japan.
| | - Toyoto Iwata
- Department of Environmental Health Sciences, Akita University Graduate School of Medicine, 1-1 Hondo, Akita City, Akita, 010-8543, Japan.
| | - Takayuki Otobe
- Department of Child Education, Jin-ai University, Echizen City, Fukui, 910-0124, Japan.
| | - Mineshi Sakamoto
- Department of Environment and Public Health, National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan.
| | - Megumi Yamamoto
- Department of Environment and Public Health, National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan.
| | - Mina Itatani
- Department of Clinical Medicine, National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan.
| | - Yoko Miura
- Department of Clinical Medicine, National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan.
| | - Chihaya Koriyama
- Department of Epidemiology and Preventive Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan.
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Yánez-Jácome GS, Romero-Estévez D, Vélez-Terreros PY, Navarrete H. Total mercury and fatty acids content in selected fish marketed in Quito - Ecuador. A benefit-risk assessment. Toxicol Rep 2023; 10:647-658. [PMID: 37250532 PMCID: PMC10220416 DOI: 10.1016/j.toxrep.2023.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 05/31/2023] Open
Abstract
Total mercury and fatty acids contents were determined in muscles of croaker, snapper, dolphinfish, blue marlin, and shark, from different markets in the Metropolitan District of Quito, Ecuador. Fifty-five samples were collected and analyzed for total mercury using cold vapor atomic fluorescence spectrometry, and the fatty acids were analyzed using gas chromatography equipped with a flame ionization detector. The lowest total mercury levels were found in snapper [0.041 µg·g-1 wet weight (ww)] while blue marlin showed the highest (5.883 µg·g-1 ww). EPA + DHA ranged from 1.0 mg·g-1 in snapper to 2.4 mg·g-1 in shark. A high omega-3/omega-6 ratio was found for all fish types; however, the HQEFA for the benefit-risk ratio was above 1, suggesting an evident risk to human health. Based on our results, consumption of croaker and dolphinfish is recommended up to one serving per week, considering the importance of EFAs intake and avoiding fish with elevated MeHg content. Therefore, Ecuadorian authorities could enhance public standards for seafood safety and develop consumer advice for pregnant women and young children to determine good fish choices or those to avoid.
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Affiliation(s)
- Gabriela S. Yánez-Jácome
- Centro de Estudios Aplicados en Química, Pontificia Universidad Católica del Ecuador, Quito 170525, Ecuador
| | - David Romero-Estévez
- Centro de Estudios Aplicados en Química, Pontificia Universidad Católica del Ecuador, Quito 170525, Ecuador
| | - Pamela Y. Vélez-Terreros
- Centro de Estudios Aplicados en Química, Pontificia Universidad Católica del Ecuador, Quito 170525, Ecuador
| | - Hugo Navarrete
- Escuela de Ciencias Biológicas, Pontificia Universidad Católica del Ecuador, Quito 170525, Ecuador
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Selenium Status: Its Interactions with Dietary Mercury Exposure and Implications in Human Health. Nutrients 2022; 14:nu14245308. [PMID: 36558469 PMCID: PMC9785339 DOI: 10.3390/nu14245308] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 12/23/2022] Open
Abstract
Selenium is an essential trace element in humans and animals and its role in selenoprotein and enzyme antioxidant activity is well documented. Food is the principal source of selenium, and it is important that selenium status in the body is adequately maintained for physiological functions. There has been increasing attention on the role of selenium in mitigating the toxic effects of mercury exposure from dietary intake in humans. In contrast, mercury is a neurotoxin, and its continuous exposure can cause adverse health effects in humans. The interactions of selenium and mercury are multi-factorial and involve complex binding mechanisms between these elements at a molecular level. Further insights and understanding in this area may help to evaluate the health implications of dietary mercury exposure and selenium status. This review aims to summarise current information on the interplay of the interactions between selenium and mercury in the body and the protective effect of selenium on at-risk groups in a population who may experience long-term mercury exposure.
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Chen Z, Lu Q, Wang J, Cao X, Wang K, Wang Y, Wu Y, Yang Z. The function of omega-3 polyunsaturated fatty acids in response to cadmium exposure. Front Immunol 2022; 13:1023999. [PMID: 36248838 PMCID: PMC9558127 DOI: 10.3389/fimmu.2022.1023999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Accepted: 09/09/2022] [Indexed: 11/13/2022] Open
Abstract
Throughout history, pollution has become a part of our daily life with the improvement of life quality and the advancement of industry and heavy industry. In recent years, the adverse effects of heavy metals, such as cadmium (Cd), on human health have been widely discussed, particularly on the immune system. Here, this review summarizes the available evidence on how Cd exposure may affect health. By analyzing the general manifestations of inflammation caused by Cd exposure, we find that the role of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) in vivo can counteract Cd-induced harm. Additionally, we elucidate the effects of n-3 PUFAs on the immune system, and analyze their prophylactic and therapeutic effects on Cd exposure. Overall, this review highlights the role of n-3 PUFAs in the pathological changes induced by Cd exposure. Although n-3 PUFAs remain to be verified whether they can be used as therapeutic agents, as rehabilitation therapy, supplementation with n-3 PUFAs is reliable and effective.
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Affiliation(s)
- Zhi Chen
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou, China
| | - Qinyue Lu
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Jiacheng Wang
- College of Medical, Yangzhou University, Yangzhou, China
| | - Xiang Cao
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Kun Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Yuhao Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Yanni Wu
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
| | - Zhangping Yang
- College of Animal Science and Technology, Yangzhou University, Yangzhou, China
- Joint International Research Laboratory of Agriculture & Agri-Product Safety, Ministry of Education, Yangzhou University, Yangzhou, China
- *Correspondence: Zhangping Yang,
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Jagodić J, Pavlović S, Borković-Mitić S, Perović M, Miković Ž, Đurđić S, Manojlović D, Stojsavljević A. Examination of Trace Metals and Their Potential Transplacental Transfer in Pregnancy. Int J Mol Sci 2022; 23:ijms23158078. [PMID: 35897677 PMCID: PMC9330144 DOI: 10.3390/ijms23158078] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/16/2022] [Accepted: 07/20/2022] [Indexed: 12/02/2022] Open
Abstract
With the ever-growing concern for human health and wellbeing, the prenatal period of development requires special attention since fetuses can be exposed to various metals through the mother. Therefore, this study explored the status of selected toxic (Pb, Cd, Ni, As, Pt, Ce, Rb, Sr, U) and essential trace metals (Mn, Co, Cu, Zn, Se) in the umbilical cord (UC) sera, maternal sera, and placental tissue samples of 92 healthy women with normal pregnancies. A further aim focuses on the potential transplacental transfer of these trace metals. Based on the obtained levels of investigated elements in clinical samples, it was observed that all of the trace metals cross the placental barrier and reach the fetus. Furthermore, statistical analysis revealed significant differences in levels of toxic Ni, As, Cd, U, Sr, Rb, and essential Mn, Cu, and Zn between all three types of analyzed clinical samples. Correlation analysis highlighted As to be an element with levels that differed significantly between all tested samples. Principal component analysis (PCA) was used to enhance these findings. PCA demonstrated that Cd, Mn, Zn, Rb, Ce, U, and Sr were the most influential trace metals in distinguishing placenta from maternal and UC serum samples. As, Co, and Cu were responsible for the clustering of maternal serum samples, and PCA demonstrated that the Pt level in UC sera was responsible for the clustering of these samples. Overall, the findings of this study could contribute to a better understanding of transplacental transfer of these trace metals, and shed a light on overall levels of metal exposure in the population of healthy pregnant women and their fetuses.
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Affiliation(s)
- Jovana Jagodić
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; (J.J.); (S.Đ.); (D.M.)
| | - Slađan Pavlović
- Institute for Biological Research “Siniša Stanković”—National Institute of the Republic of Serbia, University of Belgrade, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia; (S.P.); (S.B.-M.)
| | - Slavica Borković-Mitić
- Institute for Biological Research “Siniša Stanković”—National Institute of the Republic of Serbia, University of Belgrade, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia; (S.P.); (S.B.-M.)
| | - Milan Perović
- Clinic for Gynecology and Obstetrics Narodni Front, Faculty of Medicine University of Belgrade, Kraljice Natalije 62, 11000 Belgrade, Serbia; (M.P.); (Ž.M.)
| | - Željko Miković
- Clinic for Gynecology and Obstetrics Narodni Front, Faculty of Medicine University of Belgrade, Kraljice Natalije 62, 11000 Belgrade, Serbia; (M.P.); (Ž.M.)
| | - Slađana Đurđić
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; (J.J.); (S.Đ.); (D.M.)
| | - Dragan Manojlović
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; (J.J.); (S.Đ.); (D.M.)
| | - Aleksandar Stojsavljević
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia; (J.J.); (S.Đ.); (D.M.)
- Innovative Centre of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia
- Correspondence:
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Stojsavljević A, Perović M, Nešić A, Miković Ž, Manojlović D. Levels of non-essential trace metals and their impact on placental health: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:43662-43674. [PMID: 35426027 DOI: 10.1007/s11356-022-20205-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
According to recent research, even low levels of environmental chemicals, particularly heavy metals, can considerably disrupt placental homeostasis. This review aims to explore the profile of non-essential trace metals in placental tissues across the globe and to specify trace metal(s) that can be candidates for impaired placental health. Accordingly, we conducted an extensive survey on relevant databases of peer-reviewed papers published in the last two decades. Among a considerable number of non-essential trace metals, arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg) were identified as the most detrimental to placental health. Comparative analysis showed remarkable differences in placental levels of these trace metals worldwide. Based on current data reported across the globe, a median (min-max) range from 0.55 to 15 ng/g for placental As levels could be deemed safe. The placental Cd and Pb levels were markedly higher in smokers than in non-smokers. Occupationally exposed pregnant women had several orders of magnitude higher Cd, Pb, and Hg levels in placental tissues than non-occupationally exposed women. Also, we concluded that even low-level exposure to As, Cd, Pb, and Hg could be deleterious to proper fetal development. This review implies the need to reduce exposure to non-essential trace metals to preserve placental health and prevent numerous poor pregnancy outcomes. Overall, the information presented is expected to help plan future fundamental and applied investigations on the placental toxicity of As, Cd, Pb, and Hg.
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Affiliation(s)
- Aleksandar Stojsavljević
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000, Belgrade, Serbia.
- Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000, Belgrade, Serbia.
| | - Milan Perović
- Clinic for Gynecology and Obstetrics Narodni Front, Kraljice Natalije 62, Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, dr Subotića starijeg 8, Belgrade, Serbia
| | - Andrijana Nešić
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000, Belgrade, Serbia
| | - Željko Miković
- Clinic for Gynecology and Obstetrics Narodni Front, Kraljice Natalije 62, Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, dr Subotića starijeg 8, Belgrade, Serbia
| | - Dragan Manojlović
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000, Belgrade, Serbia
- South Ural State University, Lenin prospect 76, Chelyabinsk, Russia
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Sakamoto M, Haraguchi K, Tatsuta N, Marumoto M, Yamamoto M, Nakamura M. Breast milk contribution to tissue mercury levels in rat pups examined by cross-fostering at birth. ENVIRONMENTAL RESEARCH 2022; 208:112772. [PMID: 35063428 DOI: 10.1016/j.envres.2022.112772] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/13/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
The developing perinatal brain is vulnerable to methylmercury (MeHg) exposure. The contribution of breast milk to tissue MeHg levels in offspring is a significant public health concern because breast milk contains a certain amount of MeHg. Here, the contribution of MeHg transferred via breast milk to the Hg levels in the tissues of pups (Wistar rats) was investigated. Mated maternal rats were fed a MeHg (2 ppm)-supplemented or a control diet during pregnancy. Following parturition, male neonates from each group were cross-fostered between exposed or control dams, and they were further raised by dams fed a MeHg-supplemented diet or a control diet during lactation. Consequently, we evaluated three pup groups, which were raised by dams exposed to MeHg during pregnancy (P pups), lactation (L pups), or pregnancy and lactation (PL pups). Total mercury (THg) concentrations in the tissues of the offspring were measured at birth (postnatal day 0 [PD0]), during lactation (PD6, PD12, and PD19), and after weaning (PD29 and PD36). Blood and brain THg levels in the P and PL pups declined dramatically during lactation, however, there were no considerable differences between the two groups at PD6 and PD12. In contrast, blood and brain THg levels in the L pups increased slightly during lactation. The increase in the THg levels in the blood and brain of L pups at PD12 were approximately 3.3% and 1.5%, respectively, compared to the corresponding THg levels in the neonates in the P and PL groups. Our results suggest that if the MeHg exposure level during pregnancy is not high enough to cause neuronal development defects in the fetus, the exposure via breast milk is not a significant concern.
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Affiliation(s)
- Mineshi Sakamoto
- National Institute for Minamata Disease, Minamata, Kumamoto, 867-0008, Japan.
| | - Koichi Haraguchi
- National Institute for Minamata Disease, Minamata, Kumamoto, 867-0008, Japan
| | - Nozomi Tatsuta
- Tohoku University School of Medicine, Sendai, 880-2112, Japan
| | - Masumi Marumoto
- National Institute for Minamata Disease, Minamata, Kumamoto, 867-0008, Japan
| | - Megumi Yamamoto
- National Institute for Minamata Disease, Minamata, Kumamoto, 867-0008, Japan
| | - Masaaki Nakamura
- National Institute for Minamata Disease, Minamata, Kumamoto, 867-0008, Japan
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Stojsavljević A, Rovčanin M, Miković Ž, Perović M, Jeremić A, Zečević N, Manojlović D. Analysis of essential, toxic, rare earth, and noble elements in maternal and umbilical cord blood. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:37375-37383. [PMID: 35060029 DOI: 10.1007/s11356-021-18190-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Progressive industrialization in recent decades has contributed to the increase of metal levels in the environment, which has a dangerous impact on human health, primarily pregnant women. In this study, we aimed to compare levels of various elements in maternal and umbilical cord (UC) plasma samples collected from 125 healthy pregnant women, conduct correlation analysis among paired plasma samples, and compare our data with other populations worldwide. The study design included the following elements: essential (Mn, Co, Cu, Zn, Se, Mo), non-essential (Be, Al, Ni, As, Rb, Sr, Cd, Sb, Pb, U), rare earth (La, Pr, Ce, Nd, Sm, Eu, Gd, Dy, Ho, Er), and noble metals (Ru, Rh, Re, Pt). Levels of 30 elements were higher in maternal plasma than in UC plasma samples. However, no disparities at the statistically significant level were found for Be, Zn, Rb, Cd, Ce, and Ho. Correlation analysis among paired plasma samples revealed only positive/synergistic correlations of different strengths between most elements. Compared to other countries across the globe, our participants had considerably lower plasma levels of Zn and higher levels of Co, Ni, and As. This study provides not only a new and deeper comprehension, but also the first insight into the levels, correlation, distribution, and potential transplacental transfer of 30 elements.
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Affiliation(s)
- Aleksandar Stojsavljević
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia.
- Innovation Center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia.
| | - Marija Rovčanin
- Clinic for Gynecology and Obstetrics Narodni front, Kraljice Natalije 62, Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, dr Subotića starijeg 8, Belgrade, Serbia
| | - Željko Miković
- Clinic for Gynecology and Obstetrics Narodni front, Kraljice Natalije 62, Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, dr Subotića starijeg 8, Belgrade, Serbia
| | - Milan Perović
- Clinic for Gynecology and Obstetrics Narodni front, Kraljice Natalije 62, Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, dr Subotića starijeg 8, Belgrade, Serbia
| | - Ana Jeremić
- Clinic for Gynecology and Obstetrics Narodni front, Kraljice Natalije 62, Belgrade, Serbia
| | - Nebojša Zečević
- Clinic for Gynecology and Obstetrics Narodni front, Kraljice Natalije 62, Belgrade, Serbia
- Faculty of Medicine, University of Belgrade, dr Subotića starijeg 8, Belgrade, Serbia
| | - Dragan Manojlović
- Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia
- South Ural State University, Chelyabinsk, Lenin prospect 76, Russia
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El Hanafi K, Pedrero Z, Ouerdane L, Marchán Moreno C, Queipo-Abad S, Bueno M, Pannier F, Corns WT, Cherel Y, Bustamante P, Amouroux D. First Time Identification of Selenoneine in Seabirds and Its Potential Role in Mercury Detoxification. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3288-3298. [PMID: 35170956 DOI: 10.1021/acs.est.1c04966] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Birds are principally exposed to selenium (Se) through their diet. In long-lived and top predator seabirds, such as the giant petrel, extremely high concentrations of Se are found. Selenium speciation in biota has aroused great interest in recent years; however, there is a lack of information about the chemical form of Se in (sea)birds. The majority of publications focus on the growth performance and antioxidant status in broilers in relation to Se dietary supplementation. The present work combines elemental and molecular mass spectrometry for the characterization of Se species in wild (sea)birds. A set of eight giant petrels (Macronectes sp.) with a broad age range from the Southern Ocean were studied. Selenoneine, a Se-analogue of ergothioneine, was identified for the first time in wild avian species. This novel Se-compound, previously reported in fish, constitutes the major Se species in the water-soluble fraction of all of the internal tissues and blood samples analyzed. The levels of selenoneine found in giant petrels are the highest reported in animal tissues until now, supporting the trophic transfer in the marine food web. The characterization of selenoneine in the brain, representing between 78 and 88% of the total Se, suggests a crucial role in the nervous system. The dramatic decrease of selenoneine (from 68 to 3%) with an increase of Hg concentrations in the liver strongly supports the hypothesis of its key role in Hg detoxification.
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Affiliation(s)
- Khouloud El Hanafi
- Universite 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, 64000 Pau, France
| | - Zoyne Pedrero
- Universite 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, 64000 Pau, France
| | - Laurent Ouerdane
- Universite 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, 64000 Pau, France
| | - Claudia Marchán Moreno
- Universite 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, 64000 Pau, France
| | - Silvia Queipo-Abad
- Universite 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, 64000 Pau, France
| | - Maite Bueno
- Universite 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, 64000 Pau, France
| | - Florence Pannier
- Universite 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, 64000 Pau, France
| | - Warren T Corns
- PS Analytical, Arthur House, Crayfields Industrial Estate, Main Road, Orpington, Kent BR5 3HP, U.K
| | - Yves Cherel
- Centre d'Etudes Biologiques de Chizé, UMR 7372 CNRS-La Rochelle Université, 79360 Villiers-en-Bois, France
| | - Paco Bustamante
- Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 rue Olympe de Gouges, 17000 La Rochelle, France
- Institut Universitaire de France (IUF), 1 Rue Descartes, 75005 Paris, France
| | - David Amouroux
- Universite 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, 64000 Pau, France
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Spence T, Zavez A, Allsopp PJ, Conway MC, Yeates AJ, Mulhern MS, van Wijngaarden E, Strain JJ, Myers GJ, Watson GE, Davidson PW, Shamlaye CF, Thurston SW, McSorley EM. Serum cytokines are associated with n-3 polyunsaturated fatty acids and not with methylmercury measured in infant cord blood in the Seychelles child development study. ENVIRONMENTAL RESEARCH 2022; 204:112003. [PMID: 34492279 DOI: 10.1016/j.envres.2021.112003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/30/2021] [Accepted: 09/01/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Maternal fish consumption increases infant methylmercury (MeHg) exposure and polyunsaturated fatty acid (PUFA) concentrations. The n-3 PUFA are regulators of inflammation while MeHg may impact the cord cytokine profile and, subsequently, contribute to immune mediated outcomes. This study aimed to investigate associations between infant MeHg exposure and cord cytokine concentrations while adjusting for cord PUFA. METHODS We studied participants in the Seychelles Child Development Study (SCDS) Nutrition Cohort 2 (NC2), a large birth cohort in a high fish-eating population. Whole blood MeHg, serum PUFA and serum cytokine concentrations (IFN-γ, IL-1β, IL-2, IL-12p70, TNF-α, IL-4, IL-10, IL-13, IL-6 and IL-8) were measured in cord blood collected at delivery (n = 878). Linear regression examined associations between infant MeHg exposure and cord cytokines concentrations, with and without adjustment for cord PUFA. An interaction model examined cord MeHg, cytokines and tertiles of the n-6:n-3 ratio (low/medium/high). RESULTS There was no overall association between cord MeHg (34.08 ± 19.98 μg/L) and cytokine concentrations, with or without adjustment for PUFA. Increased total n-3 PUFA (DHA, EPA and ALA) was significantly associated with lower IL-10 (β = -0.667; p = 0.007) and lower total Th2 (IL-4, IL-10 and IL-13) (β = -0.715; p = 0.036). In the interaction model, MeHg and IL-1β was positive and significantly different from zero in the lowest n-6:n-3 ratio tertile (β = 0.002, p = 0.03). CONCLUSION Methylmercury exposure from fish consumption does not appear to impact markers of inflammation in cord blood. The association of cord n-3 PUFA with lower IL-10 and total Th2 cytokines suggests that they may have a beneficial influence on the regulation of the inflammatory milieu. These findings are important for public health advice and deserve to be investigated in follow up studies.
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Affiliation(s)
- Toni Spence
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK.
| | - Alexis Zavez
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | - Philip J Allsopp
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK
| | - Marie C Conway
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK.
| | - Alison J Yeates
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK.
| | - Maria S Mulhern
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK.
| | - Edwin van Wijngaarden
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | - J J Strain
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK.
| | - Gary J Myers
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | - Gene E Watson
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | - Philip W Davidson
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | | | - Sally W Thurston
- School of Medicine and Dentistry, University of Rochester, 601 Elmwood Avenue, Rochester, NY, 14642, USA.
| | - Emeir M McSorley
- Nutrition Innovation Centre for Food and Health, Ulster University, Coleraine, County Londonderry, BT52 1SA, UK.
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11
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Dack K, Fell M, Taylor CM, Havdahl A, Lewis SJ. Prenatal Mercury Exposure and Neurodevelopment up to the Age of 5 Years: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19041976. [PMID: 35206164 PMCID: PMC8871549 DOI: 10.3390/ijerph19041976] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/29/2022]
Abstract
Neurodevelopmental delays can interfere with children’s engagement with the world and further development, and may have negative consequences into adulthood. Mercury is highly toxic and may negatively influence neurodevelopment because it can freely cross the placenta and accumulate in the fetal brain. We searched four publication databases (Embase, PsycINFO, PubMed/MEDLINE, Scopus) for studies examining the relationship between early life mercury exposure and scores on neurodevelopmental performance measures in children aged 0 to 5 years old. Study quality was assessed using the National Institutes of Health (NIH) Quality Assessment Tool. Thirty-two prospective studies were included in the review. Neurodevelopmental performance was measured using 23 different scales, most commonly the Bayley Scales of Infant and Toddler Development (BSID). In most cases, the evidence for an association between mercury and neurodevelopment was weak. There did not appear to be exceptions for particular childhood ages, outcome scales, or mercury levels. The small number of results to the contrary were more likely to be studies which did not meet our high-quality criteria, and could be a consequence of multiple testing, selection bias, or incomplete confounder adjustment. Based on current evidence, dietary mercury exposure during pregnancy is unlikely to be a risk factor for low neurodevelopmental functioning in early childhood.
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Affiliation(s)
- Kyle Dack
- Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol BS8 1TH, UK
- Correspondence:
| | - Matthew Fell
- Cleft Collective, University of Bristol, Bristol BS8 1TH, UK;
| | - Caroline M. Taylor
- Centre for Academic Child Health, Bristol Medical School, University of Bristol, Bristol BS8 1TH, UK;
| | - Alexandra Havdahl
- Department of Mental Disorders, Norwegian Institute of Public Health, 0213 Oslo, Norway;
- Nic Waals Institute, Lovisenberg Diaconal Hospital, 0853 Oslo, Norway
| | - Sarah J. Lewis
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol BS8 1TH, UK;
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12
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Transport and Toxicity of Methylmercury-Cysteine in Cultured BeWo Cells. Int J Mol Sci 2021; 23:ijms23010394. [PMID: 35008820 PMCID: PMC8745507 DOI: 10.3390/ijms23010394] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/24/2021] [Accepted: 12/27/2021] [Indexed: 11/16/2022] Open
Abstract
Mercury is a heavy metal toxicant that is prevalent throughout the environment. Organic forms of mercury, such as methylmercury (MeHg), can cross the placenta and can lead to lasting detrimental effects in the fetus. The toxicological effects of MeHg on the placenta itself have not been clearly defined. Therefore, the purpose of the current study was to assess the transport of MeHg into placental syncytiotrophoblasts and to characterize the mechanisms by which MeHg exerts its toxic effects. Cultured placental syncytiotrophoblasts (BeWo) were used for these studies. The transport of radioactive MeHg was measured to identify potential mechanisms involved in the uptake of this compound. The toxicological effects of MeHg on BeWo cells were determined by assessing visible pathological change, autophagy, mitochondrial viability, and oxidative stress. The findings of this study suggest that MeHg compounds are transported into BeWo cells primarily by sodium-independent amino acid carriers and organic anion transporters. The MeHg altered mitochondrial function and viability, decreased mitophagy and autophagy, and increased oxidative stress. Exposure to higher concentrations of MeHg inhibited the ability of cells to protect against MeHg-induced injury. The findings show that MeHg is directly toxic to syncytiotrophoblasts and may lead to disruptions in the fetal/maternal transfer of nutrients and wastes.
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13
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Tu R, Zhang C, Feng L, Wang H, Wang W, Li P. Impact of selenium on cerebellar injury and mRNA expression in offspring of rat exposed to methylmercury. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 223:112584. [PMID: 34365210 DOI: 10.1016/j.ecoenv.2021.112584] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 07/20/2021] [Accepted: 07/29/2021] [Indexed: 06/13/2023]
Abstract
During the fetal development stage, the Central Nervous System (CNS) is particularly sensitive to methylmercury (MeHg). However, the mechanism underlying the antagonistic effect of selenium (Se) on MeHg toxicity is still not fully understood. In this study, female rat models with MeHg and Se co-exposure were developed. Pathological changes in the cerebellum and differential mRNA expression profiles in offspring rats were studied. In the MeHg-exposed group, a large number of Purkinje cells showed pathological changes and mitochondria were significantly swollen; co-exposure with Se significantly improved the structure and organization of the cerebellum. In total, 378 differentially expressed genes (DEGs) (including 284 up-regulated genes and 94 down-regulated genes) in the cerebellum of the MeHg-exposed group and 210 DEGs (including 84 up-regulated genes and 126 down-regulated genes) in the cerebellum of the MeHg+Se co-exposed group were identified. The genes involved in neurotransmitter synthesis and release and calcium ion balance in the cerebellum were significantly up-regulated in the MeHg-exposed group. These genes in the MeHg+Se co-exposed group were not changed or down-regulated. These findings demonstrate that the neurotoxicity caused by MeHg exposure is related to the up-regulation of multiple genes in the nerve signal transduction and calcium ion signal pathways, which are closely related to impairments in cell apoptosis and learning and memory. Supplementation with Se can mitigate the changes to related genes and protect neurons in the mammalian brain (especially the developing cerebellum) from MeHg toxicity. Se provides a potential intervention strategy for MeHg toxicity.
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Affiliation(s)
- Rui Tu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; Key Laboratory of Environmental Pollution Monitoring and Disease Control/School of Public Health, Guizhou Medical University, Guiyang 550025, China; Division of Infection Management, Guiyang First People's Hospital, Guiyang 550000, China
| | - Chanchan Zhang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control/School of Public Health, Guizhou Medical University, Guiyang 550025, China
| | - Ling Feng
- Key Laboratory of Environmental Pollution Monitoring and Disease Control/School of Public Health, Guizhou Medical University, Guiyang 550025, China
| | - Huiqun Wang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control/School of Public Health, Guizhou Medical University, Guiyang 550025, China
| | - Wenjuan Wang
- Key Laboratory of Environmental Pollution Monitoring and Disease Control/School of Public Health, Guizhou Medical University, Guiyang 550025, China.
| | - Ping Li
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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14
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Hadrup N, Ravn-Haren G. Absorption, distribution, metabolism and excretion (ADME) of oral selenium from organic and inorganic sources: A review. J Trace Elem Med Biol 2021; 67:126801. [PMID: 34091241 DOI: 10.1016/j.jtemb.2021.126801] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 03/26/2021] [Accepted: 05/27/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Selenium is a trace element traditionally ingested either in its organic form via food or in its inorganic form through nutritional supplements, while selenium formulated as nanoparticles is a putative long-acting alternative. To understand the physiology and toxicology of the different selenium formulations, it is important to determine how their selenium content is absorbed, distributed, metabolised and excreted; therefore, we reviewed their biokinetics following oral exposure. METHODS We retrieved and reviewed the literature on the absorption, distribution, metabolism, and excretion of oral exposure to different forms of selenium. RESULTS Selenium in both the organic form (containing carbon to selenium chemical bonds) and the inorganic form is absorbed into the blood in humans. The mean normal blood level of many studies was 139 μg/L. There are indications that selenium from organic sources is more bioavailable than selenium from inorganic sources. Selenium is distributed throughout the body, including in breast milk. The elimination of selenium mainly involves the faecal and urinary pathways, whereas breath, saliva and hair are minor contributors. Urinary metabolites include trimethylselenium ions, selenosugars and Se-methylselenoneine. CONCLUSION Selenium is absorbed to a high extent, and selenium from organic sources is more bioavailable than from inorganic sources. Selenium, as expected as an essential trace element, is distributed throughout the body. Selenium is extensively metabolised, and various excretion metabolites have been identified in both urine and breath, while some selenium is also excreted via faeces.
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Affiliation(s)
- Niels Hadrup
- The National Research Centre For The Working Environment, Lersø Park Alle 105, DK-2100, Denmark.
| | - Gitte Ravn-Haren
- National Food Institute, Technical University of Denmark, Kemitorvet, DK 2800 Kgs, Lyngby, Denmark.
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15
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Röllin HB, Channa K, Olutola B, Odland JØ. Selenium Status, Its Interaction with Selected Essential and Toxic Elements, and a Possible Sex-Dependent Response In Utero, in a South African Birth Cohort. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18168344. [PMID: 34444090 PMCID: PMC8392010 DOI: 10.3390/ijerph18168344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/03/2021] [Accepted: 08/03/2021] [Indexed: 11/16/2022]
Abstract
Selenium (Se) is an essential trace element and its deficiency in utero may affect fetus development and birth outcomes. The current study aimed to assess serum Se status at delivery and examine the possible association between Se levels and birth outcomes. The interaction of Se with selected essential and toxic elements as well as possible sex-dependent responses in utero were also evaluated. The negative association between Se levels and head circumference of neonates was evident in the total cohort (β = −0.164; p < 0.001) as well as in the pre-term and full-term cohorts. Significant positive correlations were found between maternal serum Se concentrations and zinc (Zn) and copper (Cu) in the total and regional cohorts. In the total cohort, the toxic elements lead (Pb) and arsenic (As) showed a negative correlation with Se levels, while mercury (Hg), aluminum (Al) and cadmium (Cd) showed a positive correlation. The study found a sex-dependent response in utero for Zn, Cu, Pb, Hg, and Al. The findings of the current study may inform reproductive health policy on Se status in South Africa and highlight the need for sensitive methods to measure Se intake during pregnancy and its complex interactions with other micronutrients and environmental pollutants.
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Affiliation(s)
- Halina B. Röllin
- School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria 0002, South Africa; (B.O.); (J.Ø.O.)
- Environment and Health Research Unit, South African Medical Research Council, Johannesburg 2094, South Africa
- Correspondence: ; Tel.: +27-12-356-3261
| | - Kalavati Channa
- Department of Analytical Chemistry, Lancet Laboratories, Johannesburg 2090, South Africa;
| | - Bukola Olutola
- School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria 0002, South Africa; (B.O.); (J.Ø.O.)
- School of Engineering, IT, Science and Health, Independent Institute of Education-Monash, Roodepoort 1724, South Africa
| | - Jon Øyvind Odland
- School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria 0002, South Africa; (B.O.); (J.Ø.O.)
- Department of Community Medicine and Nursing, Faculty of Health Sciences, University of Science and Technology, N-7491 Trondheim, Norway
- Department of General Hygiene, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119435 Moscow, Russia
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16
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Sakamoto M, Haraguchi K, Tatsuta N, Nakai K, Nakamura M, Murata K. Plasma and red blood cells distribution of total mercury, inorganic mercury, and selenium in maternal and cord blood from a group of Japanese women. ENVIRONMENTAL RESEARCH 2021; 196:110896. [PMID: 33640495 DOI: 10.1016/j.envres.2021.110896] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/20/2021] [Accepted: 02/15/2021] [Indexed: 06/12/2023]
Abstract
Fetuses are a high-risk group for methylmercury (MeHg) exposure. The main objective of this study was to compare the characteristic profiles of total mercury (THg), inorganic mercury (IHg), MeHg, and selenium in plasma and red blood cells (RBCs) between maternal and cord blood at parturition collected from a group of Japanese women. Furthermore, correlations of THg in RBCs, which is a biomarker of MeHg, and THg in plasma, which is an IHg exposure biomarker, were examined in maternal and cord blood. Fifty-five pairs of maternal and cord blood samples obtained at parturition were collected from pregnant women in Fukuoka, Japan. THg in RBCs and plasma were significant correlated between maternal and cord blood. THg in RBCs was 13.9 ng/mL for cord and 9.16 ng/mL for maternal blood, with a cord:maternal RBCs ratio for THg of 1.58, suggesting that MeHg is actively transferred from the mother to the fetus via the placenta. THg in plasma showed a positive correlation with THg in RBCs for maternal and cord blood. This result suggests that measuring THg in plasma can overestimate the exposure level to IHg in fish-eating populations. The percentages of IHg in cord plasma and RBCs were 31% and 1.7%, respectively, and those in maternal plasma and RBCs were 46% and 5.9%, respectively. These results suggest that cord blood is rich in MeHg and can easily transfer to the fetal brain. Selenium in cord plasma was 67 ng/mL and that in maternal plasma was 97 ng/mL, with a cord:maternal plasma ratio for Se of 0.69, suggesting that the protective effects of Se against MeHg toxicity in fetuses may be weaker than those expected in adult mothers.
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Affiliation(s)
- Mineshi Sakamoto
- National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan.
| | - Koichi Haraguchi
- National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan
| | - Nozomi Tatsuta
- Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, 980-8575, Japan
| | - Kunihiko Nakai
- Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, 980-8575, Japan
| | - Masaaki Nakamura
- National Institute for Minamata Disease, 4058-18 Hama, Minamata City, Kumamoto, 867-0008, Japan
| | - Katsuyuki Murata
- Department of Environment and Public Health, Akita University School Graduate School of Medicine, 1-1 Hondo, Akita, 010-8543, Japan
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17
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Papadopoulou E, Botton J, Caspersen IH, Alexander J, Eggesbø M, Haugen M, Iszatt N, Jacobsson B, Knutsen HK, Meltzer HM, Sengpiel V, Stratakis N, Vejrup K, Brantsæter AL. Maternal seafood intake during pregnancy, prenatal mercury exposure and child body mass index trajectories up to 8 years. Int J Epidemiol 2021; 50:1134-1146. [PMID: 33713119 PMCID: PMC8407875 DOI: 10.1093/ije/dyab035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 02/15/2021] [Indexed: 12/24/2022] Open
Abstract
Background Maternal seafood intake during pregnancy and prenatal mercury exposure may influence children’s growth trajectories. Methods This study, based on the Norwegian Mother, Father and Child Cohort Study (MoBa), includes 51 952 mother-child pairs recruited in pregnancy during 2002–08 and a subsample (n = 2277) with maternal mercury concentrations in whole blood. Individual growth trajectories were computed by modelling based on child’s reported weight and length/height from 1 month to 8 years. We used linear mixed-effects regression analysis and also conducted discordant-sibling analysis. Results Maternal lean fish was the main contributor to total seafood intake in pregnancy and was positively but weakly associated with child body mass index (BMI) growth trajectory. Higher prenatal mercury exposure (top decile) was associated with a reduction in child’s weight growth trajectory, with the estimates ranging from -130 g [95% Confidence Intervals (CI) = -247, -12 g] at 18 months to -608 g (95% CI = -1.102, -113 g) at 8 years. Maternal fatty fish consumption was positively associated with child weight and BMI growth trajectory, but only in the higher mercury-exposed children (P-interaction = 0.045). Other seafood consumption during pregnancy was negatively associated with child weight growth compared with no intake, and this association was stronger for higher mercury-exposed children (P-interaction = 0.004). No association was observed between discordant maternal seafood intake and child growth in the sibling analysis. Conclusions Within a population with moderate seafood consumption and low mercury exposure, we found that maternal seafood consumption in pregnancy was associated with child growth trajectories, and the direction of the association varied by seafood type and level of prenatal mercury exposure. Prenatal mercury exposure was negatively associated with child growth. Our findings on maternal seafood intake are likely non-causal.
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Affiliation(s)
| | - Jérémie Botton
- Faculty of Pharmacy, Univ. Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | | | - Jan Alexander
- Norwegian Institute of Public Health, Skoyen, Oslo, Norway
| | - Merete Eggesbø
- Norwegian Institute of Public Health, Skoyen, Oslo, Norway
| | | | - Nina Iszatt
- Norwegian Institute of Public Health, Skoyen, Oslo, Norway
| | - Bo Jacobsson
- Norwegian Institute of Public Health, Skoyen, Oslo, Norway.,Department of Obstetrics and Gynecology, Sahlgrenska University Hospital Gothenburg/Östra, Gothenburg, Sweden
| | | | | | - Verena Sengpiel
- Department of Obstetrics and Gynecology, Sahlgrenska University Hospital Gothenburg/Östra, Gothenburg, Sweden
| | - Nikos Stratakis
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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Abstract
The burden imposed by pollution falls more on those living in low-income and middle-income countries, affecting children more than adults. Most air pollution results from incomplete combustion and contains a mixture of particulate matter and gases. Air pollution exposure has negative impacts on respiratory health. This article concentrates on air pollution in 2 settings, the child's home and the ambient environment. There is an inextricable 2-way link between air pollution and climate change, and the effects of climate change on childhood respiratory health also are discussed.
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19
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Hossain KFB, Rahman MM, Sikder MT, Hosokawa T, Saito T, Kurasaki M. Selenium modulates inorganic mercury induced cytotoxicity and intrinsic apoptosis in PC12 cells. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 207:111262. [PMID: 32916531 DOI: 10.1016/j.ecoenv.2020.111262] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Mercury (Hg) in its all forms, including inorganic Hg (iHg) is an environmental contaminant due to toxicity and diseases in human. However, a little is known about the underlying mechanisms responsible for iHg toxicity. Selenium (Se) is an essential trace element, recognized as an antioxidant and protective agent against metal toxicities. The purpose of this research was to investigate ameliorations of Se counter to iHg-mediated toxicity in PC12 cells. Cytotoxic assays have been shown that iHg (5 μM) caused oxidative stress and intrinsic apoptosis via ROS generation, oxidizing glutathione, damaging DNA, degrading cell membrane integrity, down-regulating mTOR, p-mTOR, akt and ERK1, and up-regulating cleaved caspase 3 and cytochrome c release in PC12 cells 48 h after incubation. Co-treatment of Se (5 μM) inhibited intrinsic apoptosis and oxidative stress induced by iHg (5 μM) via inhibiting ROS formation, boosting GPx contents, increasing reduced glutathione, limiting DNA degradation, improving cell membrane integrity, up-regulating mTOR, p-mTOR, akt, ERK1 and caspase 3, and down-regulating cleaved caspase 3 and cytochrome c leakage in PC12 cells. In conclusion, these results recommended that excessive ROS generation acts a critical role in iHg-influenced oxidative stress and co-treatment of Se attenuates iHg-cytotoxicity through its antioxidant properties.
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Affiliation(s)
| | - Md Mostafizur Rahman
- Department of Environmental Sciences, Jahangirnagar University, Dhaka, 1342, Bangladesh
| | - Md Tajuddin Sikder
- Department of Public Health and Informatics, Jahangirnagar University, Dhaka, 1342, Bangladesh
| | - Toshiyuki Hosokawa
- Institute for the Advancement of Higher Education, Hokkaido University, Sapporo, 060-0817, Japan
| | - Takeshi Saito
- Faculty of Health Science, Hokkaido University, Sapporo, 060-0812, Japan
| | - Masaaki Kurasaki
- Graduate School of Environmental Science, Hokkaido University, Sapporo, 060-0810, Japan; Faculty of Environmental Earth Science, Hokkaido University, Sapporo, 060-0810, Japan.
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20
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Kim B, Shah S, Park HS, Hong YC, Ha M, Kim Y, Kim BN, Kim Y, Ha EH. Adverse effects of prenatal mercury exposure on neurodevelopment during the first 3 years of life modified by early growth velocity and prenatal maternal folate level. ENVIRONMENTAL RESEARCH 2020; 191:109909. [PMID: 32871452 DOI: 10.1016/j.envres.2020.109909] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 05/30/2020] [Accepted: 07/02/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND AND AIMS Previous studies have suggested that mercury exposure and folate levels during pregnancy may influence early childhood neurodevelopment. Rapid catch-up growth in children is associated with an increased risk of pathological nervous system development. We evaluated whether the association between prenatal folate and mercury-related neuropsychological dysfunction was modified by growth velocity during childhood. METHODS The Mothers and Children's Environmental Health (MOCEH) birth cohort study began in 2006 and by 2010, 1751 women had been enrolled before the second trimester of their pregnancy along with their partners. Participants visited the research center at birth and 6, 12, 24, and 36 months. We measured mercury levels in maternal and cord blood and folate in maternal serum. Questionnaires to evaluate the environment and health of their child were administered and anthropometric factors including body weight and height were measured. Certified investigators used the Bayley test to measure neurobehavioral outcomes. We calculated postnatal growth change as the change in infant weight for-age z-score between birth and 3 years. Multiple linear regression and mixed models were used to examine the association between mercury exposure and children's neurodevelopment as well as the modifying effects of folate and growth velocity. RESULTS A total of 30.6% of children experienced rapid growth during the first 3 years of life. Median values of mercury in the low folate group were significantly higher in rapid growers (3.41 μg/L in maternal blood and 5.63 μg/L in cord blood) than in average/slow growers (3.05 μg/L in maternal blood and 5.19 μg/L in cord blood). Rapid growers were also significantly associated with decreased psychomotor development scores during the first 3 years of life and with having mothers who had low prenatal folate levels, even after adjusting for potential confounders. CONCLUSION Prenatal mercury exposure adversely affects infant neurodevelopment and is associated with rapid growth during the first 3 years of life. This effect was limited to children whose mothers had low prenatal folate levels, suggesting a protective effect of folate against developmental neurotoxicity due to mercury exposure and rapid catch-up growth.
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Affiliation(s)
- Byungmi Kim
- National Cancer Control Institute, National Cancer Center, Goyang, Republic of Korea
| | - Surabhi Shah
- Department of Occupational and Environmental Medicine, College of Medicine, Ewha Medical Research Center, Ewha Womans University, Seoul, Republic of Korea
| | - Hye-Sook Park
- Department of Preventive Medicine, College of Medicine, Ewha Medical Research Center, Ewha Womans University, Seoul, Republic of Korea
| | - Yun-Chul Hong
- Department of Preventive Medicine, College of Medicine, Seoul National University, Seoul, Republic of Korea
| | - Mina Ha
- Department of Preventive Medicine, College of Medicine, Dankook University, Cheonan, Republic of Korea
| | - Yangho Kim
- Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea
| | - Boong-Nnyun Kim
- Division of Child & Adolescent Psychiatry, Department of Psychiatry and Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Yeni Kim
- Department of Child and Adolescent Psychiatry, National Center for Mental Health, Seoul, Republic of Korea
| | - Eun-Hee Ha
- Department of Occupational and Environmental Medicine, College of Medicine, Ewha Medical Research Center, Ewha Womans University, Seoul, Republic of Korea.
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Sakamoto M, Kakita A, Sakai K, Kameo S, Yamamoto M, Nakamura M. Methylmercury exposure during the vulnerable window of the cerebrum in postnatal developing rats. ENVIRONMENTAL RESEARCH 2020; 188:109776. [PMID: 32592939 DOI: 10.1016/j.envres.2020.109776] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/02/2020] [Accepted: 06/02/2020] [Indexed: 06/11/2023]
Abstract
The developing brain is known to be sensitive to the toxic effects of methylmercury (MeHg). The effects of toxic levels of MeHg exposure during the most seemingly vulnerable window of the cerebrum are not well studied. In this study, we aimed to examine the specific effects of toxic levels of MeHg on neurobehavior, neurodegeneration, and selenoenzyme activity in the cerebrum of infant rats. Male Wistar rats (n = 8/group) were orally treated with MeHg at an acute toxic dose (8 mg Hg/kg/day) for 10 consecutive days starting on postnatal day 14 (P14). The MeHg-exposed rats showed a significant reduction in body weight after day 8 and severe neurological symptoms similar to dystonia on day 12 (P25). Motor coordination deficits determined using the rotarod performance test and short-term memory impairment determined using the Y-maze task were observed in the MeHg-exposed rats on day 11 (P24). The MeHg-exposed rats sacrificed on day 12 showed severe cerebral neuronal degeneration, reactive astrocytosis, and TUNEL-positive apoptotic nuclei, with the cerebral Hg concentration of 15.0 ± 1.6 μg/g. Furthermore, the activities of glutathione peroxidase and thioredoxin reductase in the cerebrum in MeHg-exposed rats were lower than those in control. These results indicate that MeHg exposure to infant rats will be useful to predict the effects of MeHg at the cerebral growth spurt in humans.
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Affiliation(s)
| | - Akiyoshi Kakita
- Brain Research Institute, Niigata University, Niigata, Japan
| | - Kazuo Sakai
- Japan Institute for the Control of Aging, Nikken SEIL Co., Ltd., Japan
| | - Satomi Kameo
- Department of Public Health, Graduate School of Medicine, Gunma University, Japan; Department of Nutrition, Koshien University, Hyogo, Japan
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Zhou T, Guo J, Zhang J, Xiao H, Qi X, Wu C, Chang X, Zhang Y, Liu Q, Zhou Z. Sex-Specific Differences in Cognitive Abilities Associated with Childhood Cadmium and Manganese Exposures in School-Age Children: a Prospective Cohort Study. Biol Trace Elem Res 2020; 193:89-99. [PMID: 30977088 DOI: 10.1007/s12011-019-01703-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/19/2019] [Indexed: 01/06/2023]
Abstract
To examine sex-specific associations of neonatal and childhood exposure to eight trace elements with cognitive abilities of school-age children. The association between exposure and effects was assessed among 296 school-age children from a population-based birth cohort study, who had manganese (Mn), cadmium (Cd), and lead (Pb) exposure measured in cord blood and chromium (Cr), manganese, cobalt (Co), copper (Cu), arsenic (As), selenium (Se), cadmium, and lead exposure quantified in spot urine. Cognitive abilities were assessed using the Wechsler Intelligence Scale for Children-Chinese Revised (WISC-CR). Generalized linear models were performed to analyze associations of intelligence quotient (IQ) with trace element concentrations in cord blood and urinary trace element levels. General linear models were used to evaluate association between exposure fluctuation and children's IQ. Urinary Cd concentrations were negatively associated with full-scale IQ (β = - 3.469, 95% confidence interval (CI) - 6.291, - 0.647; p = 0.016) and performance IQ (β = - 4.012, 95% CI - 7.088, - 0.936; p = 0.011) in girls; however, neonatal Cd exposure expressed as Cd concentrations in cord blood was in inverse associations with verbal IQ (β = - 2.590, 95% CI - 4.570, - 0.609; p = 0.010) only in boys. Positive association between urinary Mn concentrations and performance IQ (β = 1.305, 95% CI 0.035, 2.575; p = 0.044) of children was observed, especially in girls. In addition, inverse association of urinary Cu concentrations with verbal IQ (β = - 2.200, 95% CI - 4.360, - 0.039; p = 0.046) was only found in boys. Childhood Cd exposure may adversely affect cognitive abilities, while Mn exposure may beneficially modify cognitive abilities of school-age children, particularly in girls.
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Affiliation(s)
- Tong Zhou
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Jianqiu Guo
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Jiming Zhang
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Hongxi Xiao
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Xiaojuan Qi
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
- Zhejiang Provincial Center for Disease Control and Prevention, No. 3399, Binsheng Road, Hangzhou, 310051, China
| | - Chunhua Wu
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Xiuli Chang
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Yubin Zhang
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Qiang Liu
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China
| | - Zhijun Zhou
- School of Public Health/Key Laboratory of Public Health Safety of Ministry of Education/Key Lab of Health Technology Assessment, National Health Commission of the People's Republic of China, Fudan University, No. 130 Dong'an Road, Shanghai, 200032, China.
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Edlow AG, Guedj F, Sverdlov D, Pennings JLA, Bianchi DW. Significant Effects of Maternal Diet During Pregnancy on the Murine Fetal Brain Transcriptome and Offspring Behavior. Front Neurosci 2019; 13:1335. [PMID: 31920502 PMCID: PMC6928003 DOI: 10.3389/fnins.2019.01335] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 11/27/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Maternal over- and undernutrition in pregnancy plays a critical role in fetal brain development and function. The effects of different maternal diet compositions on intrauterine programing of the fetal brain is a lesser-explored area. The goal of this study was to investigate the impact of two chowmaternal diets on fetal brain gene expression signatures, fetal/neonatal growth, and neonatal and adult behavior in a mouse model. METHODS Throughout pregnancy and lactation, female C57Bl/6J mice were fed one of two standard, commercially available chow diets (pellet versus powder). The powdered chow diet was relatively deficient in micronutrients and enriched for carbohydrates and n-3 long-chain polyunsaturated fatty acids compared to the pelleted chow. RNA was extracted from embryonic day 15.5 forebrains and hybridized to whole genome expression microarrays (N = 5/maternal diet group). Functional analyses of significantly differentially expressed fetal brain genes were performed using Ingenuity Pathways Analysis and Gene Set Enrichment Analysis. Neonatal behavior was assessed using a validated scale (N = 62 pellet-exposed and 31 powder-exposed). Hippocampal learning, locomotor behavior, and motor coordination were assessed in a subset of adults using fear conditioning, open field testing, and Rotarod tests (N = 16 pellet-exposed, 14 powder-exposed). RESULTS Comparing powdered to pelleted chow diets, neither maternal weight trajectory in pregnancy nor embryo size differed. Maternal powdered chow diet was associated with 1647 differentially expressed fetal brain genes. Functional analyses identified significant upregulation of canonical pathways and upstream regulators involved in cell cycle regulation, synaptic plasticity, and sensory nervous system development in the fetal brain, and significant downregulation of pathways related to cell and embryo death. Pathways related to DNA damage response, brain immune response, amino acid and fatty acid transport, and dopaminergic signaling were significantly dysregulated. Powdered chow-exposed neonates were significantly longer but not heavier than pelleted chow-exposed counterparts. On neonatal behavioral testing, powdered chow-exposed neonates achieved coordination- and strength-related milestones significantly earlier, but sensory maturation reflexes significantly later. On adult behavioral testing, powdered chow-exposed offspring exhibited hyperactivity and hippocampal learning deficits. CONCLUSION In wild-type offspring, two diets that differed primarily with respect to micronutrient composition had significant effects on the fetal brain transcriptome, neonatal and adult behavior. These effects did not appear to be mediated by alterations in gross maternal nutritional status nor fetal/neonatal weight. Maternal dietary content is an important variable to consider for investigators evaluating fetal brain development and offspring behavior.
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Affiliation(s)
- Andrea G. Edlow
- Mother Infant Research Institute, Tufts Medical Center, Boston, MA, United States
| | - Faycal Guedj
- Mother Infant Research Institute, Tufts Medical Center, Boston, MA, United States
| | - Deanna Sverdlov
- Mother Infant Research Institute, Tufts Medical Center, Boston, MA, United States
- Department of Obstetrics and Gynecology, Tufts Medical Center, Boston, MA, United States
| | | | - Diana W. Bianchi
- Mother Infant Research Institute, Tufts Medical Center, Boston, MA, United States
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Melgar MJ, Núñez R, García MÁ. Selenium intake from tuna in Galicia (Spain): Health risk assessment and protective role against exposure to mercury and inorganic arsenic. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 694:133716. [PMID: 31756789 DOI: 10.1016/j.scitotenv.2019.133716] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/31/2019] [Accepted: 07/31/2019] [Indexed: 06/10/2023]
Abstract
This study aims to quantify the selenium contribution from tuna to the Spanish diet and evidence the Se protective role against mercury and inorganic arsenic toxicity. Selenium concentrations in tuna were determined by ICP-MS spectrometry (expressed as mg kg-1), and the risk assessment was evaluated joined to Hg and iAs contrasting criteria of regulatory agencies with those that consider the Se protective role. Differences between Se average concentrations in fresh (1.24) and preserved (1.17) tuna were not statistically significant. In canned tuna species, Se presented higher mean levels in Thunnus albacares (1.28) than Thunnus alalunga (1.01) with statistically significant differences (p = 0.002), and among canned preparations a decreasing sequence was observed in different preparation-packaging media: oil (1.42) > natural (1.01) > pickled (0.92). Statistical study showed Hg-iAs as the only pair significantly correlated in all samples. The HI (sum of individual target hazard quotients -THQs-) on the consumption of tuna in Spain, due to exposure to Se, Hg and iAs, revealed the possibility of risk of adverse chronic effects in the six-year-old children group (1.09). According to the maximum allowable tuna consumption rate in meals/week (CRmw) and the THQs obtained, tuna intake, especially in children, should be moderated. The health benefit values (HBVSe) were positive in all samples, 14.53 and 15.65 in fresh and preserved tuna, respectively, which allows tuna to be considered safe. The benefit-risk value (BRV) evidenced the Se molar excess with respect to Hg that reached a surplus of 14.32% on Se AI in adults. Since iAs reduces the Se bioavailability, applying a new BRV criterion, the aforementioned percentage decreased to 13.49% of Se AI. In conclusion, tuna offers high levels of selenium to counteract adverse effects by the presence of Hg and iAs, and to provide consumers an important source of this essential element safely.
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Affiliation(s)
- M Julia Melgar
- Department of Toxicology, Faculty of Veterinary, University of Santiago de Compostela, 27002 Lugo, Spain.
| | - Ricardo Núñez
- Department of Toxicology, Faculty of Veterinary, University of Santiago de Compostela, 27002 Lugo, Spain
| | - M Ángeles García
- Department of Toxicology, Faculty of Veterinary, University of Santiago de Compostela, 27002 Lugo, Spain
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Leaf ethanolic extract of Etlingera hemesphaerica Blume alters mercuric chloride teratogenicity during the post-implantation period in Mus musculus. Toxicol Res 2019; 36:131-138. [PMID: 32257925 DOI: 10.1007/s43188-019-00010-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 06/01/2019] [Accepted: 06/25/2019] [Indexed: 02/06/2023] Open
Abstract
This study aimed to investigate the effectiveness of leaf ethanolic extract of Etlingera hemisphaerica (LE3H) against the teratogenic effects of mercuric chloride (HgCl2) in mice (Mus musculus). Pregnant M. musculus were divided into four groups, each consisting of 10 dams, and received drink and food ad libitum. The first, second, and third, and fourth (control) groups were administered with LE3H, HgCl2, HgCl2 + LE3H, and double-distilled water alone, respectively. HgCl2 (5 mg/kg bw) was administered by injection on gestation day (GD) 9, and LE3H (0.39 mg/g bw) was administered by gavage on GD 10. Treated and control animals were killed by cervical dislocation on GD 18, dissected, and the fetuses were collected for evaluation of maternal, embryonic, and fetal toxicity. Eight parameters were measured: (a) embryo resorption or resorbed embryo, (b) dead fetus, (c) living fetus, (d) morphologically normal living fetus, (e) malformed living fetus, (f) number of MLF, (g) length of MNLF, and (h) weight of MNLF. LE3H caused 4 (50.00%), whereas HgCl2 resulted in 7 (87.50%) parameters that were significantly different from those of the control, indicating that the teratogenicity of HgCl2 was significantly higher than that of LE3H. HgCl2 + LE3H showed two effects of LE3H on the teratogenicity of HgCl2: increased 2 (25.00%), and decreased 6 (75.00%). Thus, LE3H decreased the teratogenic effects of HgCl2 in M. musculus.
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Falck AJ, Sundararajan S, Al-Mudares F, Contag SA, Bearer CF. Fetal exposure to mercury and lead from intrauterine blood transfusions. Pediatr Res 2019; 86:510-514. [PMID: 31216568 DOI: 10.1038/s41390-019-0463-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 06/04/2019] [Accepted: 06/12/2019] [Indexed: 11/09/2022]
Abstract
BACKGROUND Mercury (Hg) and lead (Pb) exposure during childhood is associated with irreversible neurodevelopmental effects. Fetal exposure to Hg and Pb from intrauterine blood transfusion (IUBT) has not been reported. METHODS Fetal exposure was estimated based on transfusion volume and metal concentration in donor packed red blood cell (PRBCs). As biomarkers to quantify prenatal exposure are unknown, Hg and Pb in donor PRBCs were compared to estimated intravenous (IV) RfDs based on gastrointestinal absorption. RESULTS Three pregnant women received 8 single-donor IUBTs with volumes ranging from 19 to 120 mL/kg. Hg and Pb were present in all donor PRBC units. In all, 1/8 IUBT resulted in Hg dose five times higher than the estimated IV RfD. Median Pb dose in one fetus who received 5 single-donor IUBTs between 20-32 weeks gestation was 3.4 μg/kg (range 0.5-7.9 μg/kg). One donor unit contained 12.9 μg/dL of Pb, resulting in a fetal dose of 7.9 μg/kg, 40 times higher than the estimated IV RfD at 20 weeks gestation. CONCLUSION This is the first study documenting inadvertent exposure to Hg and Pb from IUBT and quantifying the magnitude of exposure. Screening of donor blood is warranted to prevent toxic effects from Hg and Pb to the developing fetus.
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Affiliation(s)
- Alison J Falck
- Division of Neonatology, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Sripriya Sundararajan
- Division of Neonatology, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - Stephen A Contag
- Department of Obstetrics, Gynecology and Women's Health, University of Minnesota, Minneapolis, MN, USA
| | - Cynthia F Bearer
- Division of Neonatology, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA
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Schofield K. An Important Need to Monitor from an Early Age the Neurotoxins in the Blood or by an Equivalent Biomarker. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16183425. [PMID: 31527390 PMCID: PMC6766009 DOI: 10.3390/ijerph16183425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 09/12/2019] [Accepted: 09/13/2019] [Indexed: 12/17/2022]
Abstract
An overwhelming amount of evidence now suggests that some people are becoming overloaded with neurotoxins. This is mainly from changes in their living environment and style, coupled with the fact that all people are different and display a broad distribution of genetic susceptibilities. It is important for individuals to know where they lie concerning their ability to either reject or retain toxins. Everyone is contaminated with a certain baseline of toxins that are alien to the body, namely aluminum, arsenic, lead, and mercury. Major societal changes have modified their intake, such as vaccines in enhanced inoculation procedures and the addition of sushi into diets, coupled with the ever-present lead, arsenic, and traces of manganese. It is now apparent that no single toxin is responsible for the current neurological epidemics, but rather a collaborative interaction with possible synergistic components. Selenium, although also a neurotoxin if in an excessive amount, is always present and is generally more present than other toxins. It performs as the body’s natural chelator. However, it is possible that the formation rates of active selenium proteins may become overburdened by other toxins. Every person is different and it now appears imperative that the medical profession establish an individual’s neurotoxicity baseline. Moreover, young women should certainly establish their baselines long before pregnancy in order to identify possible risk factors.
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Affiliation(s)
- Keith Schofield
- Materials Research Laboratory, University of California Santa Barbara, Santa Barbara, CA 93106-5121, USA.
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Iwai-Shimada M, Kameo S, Nakai K, Yaginuma-Sakurai K, Tatsuta N, Kurokawa N, Nakayama SF, Satoh H. Exposure profile of mercury, lead, cadmium, arsenic, antimony, copper, selenium and zinc in maternal blood, cord blood and placenta: the Tohoku Study of Child Development in Japan. Environ Health Prev Med 2019; 24:35. [PMID: 31101007 PMCID: PMC6525413 DOI: 10.1186/s12199-019-0783-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 04/11/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND The effects of prenatal exposure to toxic elements on birth outcomes and child development have been an area of concern. This study aimed to assess the profile of prenatal exposure to toxic elements, arsenic (As), bismuth (Bi), cadmium (Cd), mercury (total mercury (THg), methylmercury (MHg), inorganic mercury (IHg)), lead (Pb), antimony (Sb) and tin (Sn), and essential trace elements, copper (Cu), selenium (Se) and zinc (Zn), using the maternal blood, cord blood and placenta in the Tohoku Study of Child Development of Japan (N = 594-650). METHODS Inductively coupled plasma mass spectrometry was used to determine the concentrations of these elements (except mercury). Levels of THg and MeHg were measured using cold vapour atomic absorption spectrophotometry and a gas chromatograph-electron capture detector, respectively. RESULTS Median concentrations (25th-75th) of As, Cd, Pb, Sb, Sn and THg in the maternal blood were 4.06 (2.68-6.81), 1.18 (0.74-1.79), 10.8 (8.65-13.5), 0.2 (0.06-0.40) and 0.2 (0.1-0.38) ng mL-1 and 5.42 (3.89-7.59) ng g-1, respectively. Median concentrations (25th-75th) of As, Cd, Pb, Sb, Sn and THg in the cord blood were 3.68 (2.58-5.25), 0.53 (0.10-1.25), 9.89 (8.02-12.5), 0.39 (0.06-0.92) and 0.2 (0.2-0.38) ng mL-1 and 9.96 (7.05-13.8) ng g-1, respectively. CONCLUSIONS THg and Sb levels in the cord blood were twofold higher than those in the maternal blood. Cord blood to maternal blood ratios for As, Cd and Sb widely varied between individuals. To understand the effects of prenatal exposure, further research regarding the variations of placental transfer of elements is necessary.
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Affiliation(s)
- Miyuki Iwai-Shimada
- Centre for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan.
| | - Satomi Kameo
- Department of Nutrition, College of Nutrition, Koshien University, Takarazuka, Hyogo, Japan
| | - Kunihiko Nakai
- Department of Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Kozue Yaginuma-Sakurai
- Department of Human Health and Nutrition, Faculty of Comprehensive Human Sciences, Shokei Gakuin University, Sendai, Miyagi, Japan
| | - Nozomi Tatsuta
- Department of Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | | | - Shoji F Nakayama
- Centre for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
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Rahman MM, Hossain KFB, Banik S, Sikder MT, Akter M, Bondad SEC, Rahaman MS, Hosokawa T, Saito T, Kurasaki M. Selenium and zinc protections against metal-(loids)-induced toxicity and disease manifestations: A review. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 168:146-163. [PMID: 30384162 DOI: 10.1016/j.ecoenv.2018.10.054] [Citation(s) in RCA: 91] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 10/12/2018] [Accepted: 10/13/2018] [Indexed: 06/08/2023]
Abstract
Metals are ubiquitous in the environment due to huge industrial applications in the form of different chemicals and from extensive mining activities. The frequent exposures to metals and metalloids are crucial for the human health. Trace metals are beneficial for health whereas non-essential metals are dangerous for the health and some are proven etiological factors for diseases including cancers and neurological disorders. The interactions of essential trace metals such as selenium (Se) and zinc (Zn) with non-essential metals viz. lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in biological system are very critical and complex. A huge number of studies report the protective role of Se and Zn against metal toxicity, both in animal and cellular levels, and also explain the numerous mechanisms involved. However, it has been considered that a tiny dyshomeostasis in the metals/trace metals status in biological system could induce severe deleterious effects that can manifest to numerous diseases. Thus, in this particular review, we have demonstrated the critical protection mechanism/s of Se and Zn against Cd, Pb, As and Hg toxicity in a one by one manner to clarify the up-to-date findings and perspectives. Furthermore, biomolecular consequences are comprehensively presented in light of particular cellular/biomolecular events which are somehow linked to a subsequent disease. The analyzed reports support significant protection potential of Se and Zn, either alone or in combination with other agents, against each of the abovementioned non-essential metals. However, Se and Zn are still not being used as detoxifying agents due to some unexplained reasons. We hypothesized that Se could be a potential candidate for detoxifying As and Hg regardless of their chemical speciations, but requires intensive clinical trials. However, particularly Zn-Hg interaction warrants more investigations both in animal and cellular level.
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Affiliation(s)
- Md Mostafizur Rahman
- Graduate School of Environmental Science, Hokkaido University, 060-0810 Sapporo, Japan; Department of Environmental Sciences, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh
| | | | - Subrata Banik
- Graduate School of Environmental Science, Hokkaido University, 060-0810 Sapporo, Japan
| | - Md Tajuddin Sikder
- Graduate School of Environmental Science, Hokkaido University, 060-0810 Sapporo, Japan; Faculty of Health Sciences, Hokkaido University, 060-0812 Sapporo, Japan
| | - Mahmuda Akter
- Graduate School of Environmental Science, Hokkaido University, 060-0810 Sapporo, Japan
| | | | - Md Shiblur Rahaman
- Graduate School of Environmental Science, Hokkaido University, 060-0810 Sapporo, Japan
| | - Toshiyuki Hosokawa
- Research Division of Higher Education, Institute for the Advancement of Higher Education, Hokkaido University, 060-0817 Sapporo, Japan
| | - Takeshi Saito
- Faculty of Health Sciences, Hokkaido University, 060-0812 Sapporo, Japan
| | - Masaaki Kurasaki
- Graduate School of Environmental Science, Hokkaido University, 060-0810 Sapporo, Japan; Faculty of Environmental Earth Science, Hokkaido University, 060-0810 Sapporo, Japan.
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Mahdi H, Tahereh H, Esmaiel S, Massood E. Vitamins E and C prevent apoptosis of testicular and ovarian tissues following mancozeb exposure in the first-generation mouse pups. Toxicol Ind Health 2019; 35:136-144. [PMID: 30651039 DOI: 10.1177/0748233718818692] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this study was to evaluate the role of apoptosis in the first-generation pups' testicular and ovarian tissue changes following mancozeb (MNZ) administration during intrauterine and lactating periods and also the preventive effect of the co-administration of vitamins E and C on these changes. Naval Medical Research Institute (NMRI) pregnant mice were randomly divided into six groups: control, vehicle, MNZ, vitamin E plus MNZ, vitamin C plus MNZ and vitamins E and C plus MNZ. Administered doses of MNZ and vitamins E and C were 500, 200 and 100 mg/kg of body weight, respectively. These agents were administered to the animals by oral gavage every 2 days. Vitamin treatment was carried out 30 min prior to MNZ administration. Treatment was started on the second day of gestation and continued until weaning. Separated testes and ovaries of animals were prepared for apoptosis detection by terminal deoxynucleotidyl transferase end-labeling (TUNEL) staining. The percentage of TUNEL-positive cells was reported using the 4,6-diamidino-2-phenylindole method. As compared to the control and vehicle groups, MNZ induced a significant increase ( p < 0.001) in the number of TUNEL-positive cells. The administration of both vitamins E and C alone and together significantly ( p < 0.001) prevented the apoptotic impacts of MNZ. The preventive effect of the co-administration of these vitamins on the ovary was greater compared to the single administration of vitamins E ( p < 0.001) or C ( p < 0.001). Meanwhile, the results revealed the stronger preventive effect of vitamin C as compared to E on testicular tissue ( p < 0.05). The apoptotic impact of MNZ exposure during intrauterine and lactating periods on first-generation testicular and ovarian tissues was significant. The co-administration of vitamins E and C could prevent MNZ-induced testicular and ovarian changes.
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Affiliation(s)
- Heydari Mahdi
- 1 Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Haghpanah Tahereh
- 1 Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Saddein Esmaiel
- 1 Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Ezzatabadipour Massood
- 1 Department of Anatomical Sciences, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
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Maeda E, Murata K, Kumazawa Y, Sato W, Shirasawa H, Iwasawa T, Izumo K, Tatsuta N, Sakamoto M, Terada Y. Associations of environmental exposures to methylmercury and selenium with female infertility: A case-control study. ENVIRONMENTAL RESEARCH 2019; 168:357-363. [PMID: 30384229 DOI: 10.1016/j.envres.2018.10.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Revised: 09/13/2018] [Accepted: 10/03/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND Methylmercury exposure is a common health risk resulting from daily fish intake. However, studies addressing the link between methylmercury and infertility are limited and also inconsistent. In addition, no previous epidemiological studies have accounted for the interaction between methylmercury and selenium. We aimed to investigate the association between environmental exposures to metals and female fertility. METHODS This case-control study included 98 infertile women receiving fertility treatment (infertile group) and 43 female workers in their thirties (control group) who provided blood samples and returned a questionnaire on lifestyles and dietary characteristics. Blood levels of mercury, lead, cadmium, arsenic, manganese, zinc, and selenium were compared between the groups. Spearman correlation analyses between anti-Müllerian hormone and the metals were conducted. RESULTS The mean selenium level in blood (± SD) and the selenium/mercury molar ratio were significantly lower in the infertile group (189 ± 25 μg/L and 94.6 ± 44.3, respectively) than in the control group (200 ± 25 μg/L and 118.4 ± 70.5). By contrast, blood mercury levels after adjusting for blood selenium and age were significantly higher in the infertile group than in the control group. Multiple logistic regression analyses with the adjustment for the other metals and potential confounders confirmed significant associations of infertility with elevated mercury and reduced selenium levels. No significant correlations were observed between anti-Müllerian hormone and metals. CONCLUSIONS Methylmercury and selenium exposures appear to have adverse and protective effects on female fertility, respectively. This is the first report to suggest the antagonistic interaction between methylmercury and selenium in relation to human female fertility.
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Affiliation(s)
- Eri Maeda
- Department of Environmental Health Sciences, Akita University Graduate School of Medicine, Akita, Japan
| | - Katsuyuki Murata
- Department of Environmental Health Sciences, Akita University Graduate School of Medicine, Akita, Japan.
| | - Yukiyo Kumazawa
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita, Japan
| | - Wataru Sato
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita, Japan
| | - Hiromitsu Shirasawa
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita, Japan
| | - Takuya Iwasawa
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita, Japan
| | - Kimiko Izumo
- Department of Environment and Public Health, National Institute for Minamata Disease, Kumamoto, Japan
| | - Nozomi Tatsuta
- Department of Environmental Health Sciences, Akita University Graduate School of Medicine, Akita, Japan; Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Miyagi, Japan
| | - Mineshi Sakamoto
- Department of Environment and Public Health, National Institute for Minamata Disease, Kumamoto, Japan
| | - Yukihiro Terada
- Department of Obstetrics and Gynecology, Akita University Graduate School of Medicine, Akita, Japan
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Sakamoto M, Tatsuta N, Chan HM, Domingo JL, Murata K, Nakai K. Brain methylmercury uptake in fetal, neonate, weanling, and adult rats. ENVIRONMENTAL RESEARCH 2018; 167:15-20. [PMID: 30005196 DOI: 10.1016/j.envres.2018.06.038] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/15/2018] [Accepted: 06/18/2018] [Indexed: 06/08/2023]
Abstract
Fetuses and neonates are known to be highly susceptible to methylmercury (MeHg) toxicity, but little is known about the relative uptake of MeHg from blood to the developing brain. We measured time-course changes in mercury (Hg) concentrations in the brain of fetal, neonate, weanling, and adult rats after an injection of 0.08 μg (0.4 nmol) Hg/g MeHg. In the prenatal experiment, MeHg was subcutaneously injected to pregnant dams on embryonic days 17, 18, 18.5, 19, 19.5, or 20, and Hg concentrations in tissues were measured in both mothers and fetuses on embryonic day 21 (1 day before parturition). Brain Hg levels in fetuses peaked 2 days after injection and were approximately 1.5 times higher than in mothers. In the postnatal experiment, the same MeHg dose was injected subcutaneously to male rats on postnatal days 1 (neonates), 35 (weanlings), or 56 (adults). Mercury concentrations in tissues were measured 1, 2, 3, 4, 5, or 6 days after the injection. Brain Hg levels peaked most rapidly in neonates, and were approximately 1.5 times higher than levels in weanlings or adults. Throughout the examined period, peak Hg levels in the brain and the Hg brain/blood ratio 24 h after injection were highest in fetuses, followed by the levels in neonates, and decreased with life stage. These findings suggest that relatively higher brain MeHg uptake is an important factor in the vulnerability of fetuses and neonates to MeHg exposure.
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Affiliation(s)
- Mineshi Sakamoto
- Department of Environment and Public Health, National Institute for Minamata Disease, 4058-18 Hama, Kumamoto 867-0008, Japan; Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan.
| | - Nozomi Tatsuta
- Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hing Man Chan
- Center for Advanced Research in Environmental Genomics, Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - José L Domingo
- Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat "Rovira I Virgili", Reus, Spain
| | - Katsuyuki Murata
- Department of Environmental Health Sciences, Akita University School of Medicine, Akita, Japan
| | - Kunihiko Nakai
- Development and Environmental Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
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Sub-Nanomolar Methylmercury Exposure Promotes Premature Differentiation of Murine Embryonic Neural Precursor at the Expense of Their Proliferation. TOXICS 2018; 6:toxics6040061. [PMID: 30308979 PMCID: PMC6315723 DOI: 10.3390/toxics6040061] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 09/28/2018] [Accepted: 10/03/2018] [Indexed: 11/17/2022]
Abstract
Methylmercury (MeHg) is a ubiquitous environmental pollutant that is known to be neurotoxic, particularly during fetal development. However, the mechanisms responsible for MeHg-induced changes in adult neuronal function, when their exposure occurred primarily during fetal development, are not yet understood. We hypothesized that fetal MeHg exposure could affect neural precursor development leading to long-term neurotoxic effects. Primary cortical precursor cultures obtained from embryonic day 12 were exposed to 0 µM, 0.25 µM, 0.5 µM, 2.5 µM, and 5 µM MeHg for 48 or 72 h. All of the concentrations tested in the study did not affect cell viability. Intriguingly, we observed that cortical precursor exposed to 0.25 µM MeHg showed increased neuronal differentiation, while its proliferation was inhibited. Reduced neuronal differentiation, however, was observed in the higher dose groups. Our results suggest that micromolar MeHg exposure may deplete the pool of neural precursors by increasing premature neuronal differentiation, which can lead to long-term neurological effects in adulthood as opposed to the higher MeHg doses that cause more immediate toxicity during infant development.
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Health Impacts and Biomarkers of Prenatal Exposure to Methylmercury: Lessons from Minamata, Japan. TOXICS 2018; 6:toxics6030045. [PMID: 30081479 PMCID: PMC6161157 DOI: 10.3390/toxics6030045] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/26/2018] [Accepted: 07/31/2018] [Indexed: 12/03/2022]
Abstract
The main chemical forms of mercury are elemental mercury, inorganic divalent mercury, and methylmercury, which are metabolized in different ways and have differing toxic effects in humans. Among the various chemical forms of mercury, methylmercury is known to be particularly neurotoxic, and was identified as the cause of Minamata disease. It bioaccumulates in fish and shellfish via aquatic food webs, and fish and sea mammals at high trophic levels exhibit high mercury concentrations. Most human methylmercury exposure occurs through seafood consumption. Methylmercury easily penetrates the blood-brain barrier and so can affect the nervous system. Fetuses are known to be at particularly high risk of methylmercury exposure. In this review, we summarize the health effects and exposure assessment of methylmercury as follows: (1) methylmercury toxicity, (2) history and background of Minamata disease, (3) methylmercury pollution in the Minamata area according to analyses of preserved umbilical cords, (4) changes in the sex ratio in Minamata area, (5) neuropathology in fetuses, (6) kinetics of methylmercury in fetuses, (7) exposure assessment in fetuses.
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