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Galiciolli MEA, Silva JF, Prodocimo MM, Laureano HA, Calado SLDM, Oliveira CS, Guiloski IC. Toxicological Effects of Thimerosal and Aluminum in the Liver, Kidney, and Brain of Zebrafish ( Danio rerio). Metabolites 2023; 13:975. [PMID: 37755255 PMCID: PMC10537066 DOI: 10.3390/metabo13090975] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/18/2023] [Accepted: 08/23/2023] [Indexed: 09/28/2023] Open
Abstract
Vaccination programs in the first years of a child's life are effective and extremely important strategies for the successful eradication of diseases. However, as no intervention is without risks, the metal-based components of some vaccines, such as thimerosal (TMS), a preservative composed of ethylmercury, and aluminum (Al), have begun to generate distrust on the part of the population. Therefore, this study evaluated the effects of exposure to thimerosal and aluminum hydroxide (alone or in mixture) on Danio rerio (zebrafish) specimens. The fish were exposed to thimerosal and/or aluminum hydroxide intraperitoneally. The liver, kidney, and brain were removed for a biochemical biomarker analysis, histopathological analysis, and metal quantification. As a result, we observed changes in the activity of the analyzed enzymes (SOD, GST, GPx) in the kidney and brain of the zebrafish, a reduction in GSH levels in all analyzed tissues, and a reduction in MT levels in the kidney and liver as well as in the brain. Changes in AChE enzyme activity were observed. The biochemical results corroborate the changes observed in the lesion index and histomorphology sections. We emphasize the importance of joint research on these compounds to increase the population's safety against their possible toxic effects.
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Affiliation(s)
- Maria Eduarda Andrade Galiciolli
- Instituto de Pesquisa Pelé Pequeno Príncipe, Avenida Silva Jardim, 1632, Água Verde, Curitiba 80250-200, PR, Brazil; (M.E.A.G.); (J.F.S.)
- Faculdades Pequeno Príncipe, Curitiba 80230-020, PR, Brazil
| | - Juliana Ferreira Silva
- Instituto de Pesquisa Pelé Pequeno Príncipe, Avenida Silva Jardim, 1632, Água Verde, Curitiba 80250-200, PR, Brazil; (M.E.A.G.); (J.F.S.)
- Faculdades Pequeno Príncipe, Curitiba 80230-020, PR, Brazil
| | - Maritana Mela Prodocimo
- Departamento de Biologia Celular e Molecular, Universidade Federal do Paraná, Centro Politécnico, Avenida Cel. Francisco H. dos Santos, 100—Jardim das Américas, Curitiba—PR, Curitiba 81531-980, PR, Brazil;
| | - Henrique Aparecido Laureano
- Instituto de Pesquisa Pelé Pequeno Príncipe, Avenida Silva Jardim, 1632, Água Verde, Curitiba 80250-200, PR, Brazil; (M.E.A.G.); (J.F.S.)
- Faculdades Pequeno Príncipe, Curitiba 80230-020, PR, Brazil
| | | | - Claudia Sirlene Oliveira
- Instituto de Pesquisa Pelé Pequeno Príncipe, Avenida Silva Jardim, 1632, Água Verde, Curitiba 80250-200, PR, Brazil; (M.E.A.G.); (J.F.S.)
- Faculdades Pequeno Príncipe, Curitiba 80230-020, PR, Brazil
| | - Izonete Cristina Guiloski
- Instituto de Pesquisa Pelé Pequeno Príncipe, Avenida Silva Jardim, 1632, Água Verde, Curitiba 80250-200, PR, Brazil; (M.E.A.G.); (J.F.S.)
- Faculdades Pequeno Príncipe, Curitiba 80230-020, PR, Brazil
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Azevedo LF, Karpova N, Rocha BA, Barbosa Junior F, Gobe GC, Hornos Carneiro MF. Evidence on Neurotoxicity after Intrauterine and Childhood Exposure to Organomercurials. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:1070. [PMID: 36673825 PMCID: PMC9858833 DOI: 10.3390/ijerph20021070] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
Although the molecular mechanisms underlying methylmercury toxicity are not entirely understood, the observed neurotoxicity in early-life is attributed to the covalent binding of methylmercury to sulfhydryl (thiol) groups of proteins and other molecules being able to affect protein post-translational modifications from numerous molecular pathways, such as glutamate signaling, heat-shock chaperones and the antioxidant glutaredoxin/glutathione system. However, for other organomercurials such as ethylmercury or thimerosal, there is not much information available. Therefore, this review critically discusses current knowledge about organomercurials neurotoxicity-both methylmercury and ethylmercury-following intrauterine and childhood exposure, as well as the prospects and future needs for research in this area. Contrasting with the amount of epidemiological evidence available for methylmercury, there are only a few in vivo studies reporting neurotoxic outcomes and mechanisms of toxicity for ethylmercury or thimerosal. There is also a lack of studies on mechanistic approaches to better investigate the pathways involved in the potential neurotoxicity caused by both organomercurials. More impactful follow-up studies, especially following intrauterine and childhood exposure to ethylmercury, are necessary. Childhood vaccination is critically important for controlling infectious diseases; however, the safety of mercury-containing thimerosal and, notably, its effectiveness as preservative in vaccines are still under debate regarding its potential dose-response effects to the central nervous system.
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Affiliation(s)
- Lara Ferreira Azevedo
- Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, SP, Brazil
| | - Nina Karpova
- Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, SP, Brazil
| | - Bruno Alves Rocha
- Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, SP, Brazil
| | - Fernando Barbosa Junior
- Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto 14040-903, SP, Brazil
| | - Glenda Carolyn Gobe
- Kidney Disease Research Group, School of Medicine, Translational Research Institute, University of Queensland, 37 Kent Street, Woolloongabba, QLD 4102, Australia
| | - Maria Fernanda Hornos Carneiro
- Department of Pharmacy, Faculty of Chemistry and Pharmacy, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile
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Barajas MB, Wang A, Griffiths KK, Sun L, Yang G, Levy RJ. Modeling propofol-induced cardiotoxicity in the isolated-perfused newborn mouse heart. Physiol Rep 2022; 10:e15402. [PMID: 35923108 PMCID: PMC9350423 DOI: 10.14814/phy2.15402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 06/24/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023] Open
Abstract
Infants and children are vulnerable to developing propofol infusion syndrome (PRIS) and young age is a risk factor. Cardiac involvement is often prominent and associated with death. However, the mechanisms of pediatric PRIS are poorly understood because of the paucity of investigation and lack of a gold standard animal model. Unfortunately, in vivo modeling of PRIS in a newborn mouse is not feasible and would be complicated by confounders. Thus, we focused on propofol-induced cardiotoxicity and aimed to develop an ex-vivo model in the isolated-perfused newborn mouse heart. We hypothesized that the model would recapitulate the key cardiac features of PRIS seen in infants and children and would corroborate prior in vitro observations. Isolated perfused newborn mouse hearts were exposed to a toxic dose of propofol or intralipid for 30-min. Surface electrocardiogram, ventricular contractile force, and oxygen extraction were measured over time. Real-time multiphoton laser imaging was utilized to quantify calcein and tetramethylrhodamine ethyl ester fluorescence. Propidium iodide uptake was assessed following drug exposure. A toxic dose of propofol rapidly induced dysrhythmias, depressed ventricular contractile function, impaired the mitochondrial membrane potential, and increased open probability of the permeability transition pore in propofol-exposed hearts without causing cell death. These features mimicked the hallmarks of pediatric PRIS and corroborated prior observations made in isolated newborn cardiomyocyte mitochondria. Thus, acute propofol-induced cardiotoxicity in the isolated-perfused developing mouse heart may serve as a relevant ex-vivo model for pediatric PRIS.
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Affiliation(s)
- Matthew B. Barajas
- Department of AnesthesiologyColumbia University Medical CenterNew YorkNew YorkUSA
| | - Aili Wang
- Department of AnesthesiologyColumbia University Medical CenterNew YorkNew YorkUSA
| | - Keren K. Griffiths
- Department of AnesthesiologyColumbia University Medical CenterNew YorkNew YorkUSA
| | - Linlin Sun
- Department of AnesthesiologyColumbia University Medical CenterNew YorkNew YorkUSA
| | - Guang Yang
- Department of AnesthesiologyColumbia University Medical CenterNew YorkNew YorkUSA
| | - Richard J. Levy
- Department of AnesthesiologyColumbia University Medical CenterNew YorkNew YorkUSA
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4
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Barajas MB, Brunner SD, Wang A, Griffiths KK, Levy RJ. Propofol toxicity in the developing mouse heart mitochondria. Pediatr Res 2022; 92:1341-1349. [PMID: 35173299 PMCID: PMC9378757 DOI: 10.1038/s41390-022-01985-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/16/2021] [Accepted: 01/30/2022] [Indexed: 12/02/2022]
Abstract
BACKGROUND Propofol infusion syndrome (PRIS) is a potentially lethal consequence of long-term propofol administration. Children are vulnerable and cardiac involvement is often prominent and associated with mortality. We aimed to determine the mechanism of propofol toxicity in newborn mice, hypothesizing that propofol would induce discrete defects within immature cardiac mitochondria. METHODS Newborn murine cardiac mitochondria were exposed to propofol or intralipid in vitro. Non-exposed mitochondria served as controls. Mitochondrial respiration and membrane potential (ΔΨ) were measured and respiratory chain complex kinetics were determined. RESULTS Propofol and intralipid exerted biological activity in isolated mitochondria. Although intralipid effects were a potential confounder, we found that propofol induced a dose-dependent increase in proton leak and caused a defect in substrate oxidation at coenzyme Q (CoQ). These impairments prevented propofol-exposed cardiomyocyte mitochondria from generating an adequate ΔΨ. The addition of the quinone analog, CoQ0, blocked propofol-induced leak and increased Complex II+III activity. CONCLUSIONS Propofol uncoupled immature cardiomyocyte mitochondria by inducing excessive CoQ-sensitive leak and interfered with electron transport at CoQ. The findings provide new insight into the mechanisms of propofol toxicity in the developing heart and may help explain why children are vulnerable to developing PRIS. IMPACT Propofol uncouples immature cardiomyocyte mitochondria by inducing excessive coenzyme Q (CoQ)-sensitive proton leak. Propofol also interferes with electron transport at the level of CoQ. These defects provide new insight into propofol toxicity in the developing heart.
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Affiliation(s)
- Matthew B. Barajas
- grid.239585.00000 0001 2285 2675Department of Anesthesiology, Columbia University Medical Center, New York, NY USA
| | - Sarah D. Brunner
- grid.239585.00000 0001 2285 2675Department of Pediatrics, Division of Pediatric Critical Care Medicine, Columbia University Medical Center, New York, NY USA
| | - Aili Wang
- grid.239585.00000 0001 2285 2675Department of Anesthesiology, Columbia University Medical Center, New York, NY USA
| | - Keren K. Griffiths
- grid.239585.00000 0001 2285 2675Department of Anesthesiology, Columbia University Medical Center, New York, NY USA
| | - Richard J. Levy
- grid.239585.00000 0001 2285 2675Department of Anesthesiology, Columbia University Medical Center, New York, NY USA
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Bairwa SC, Shaw CA, Kuo M, Yoo J, Tomljenovic L, Eidi H. Cytokines profile in neonatal and adult wild-type mice post-injection of U. S. pediatric vaccination schedule. Brain Behav Immun Health 2021; 15:100267. [PMID: 34589773 PMCID: PMC8474652 DOI: 10.1016/j.bbih.2021.100267] [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: 01/08/2021] [Revised: 05/02/2021] [Accepted: 05/03/2021] [Indexed: 11/09/2022] Open
Abstract
Introduction A recent study from our laboratory demonstrated a number of neurobehavioral abnormalities in mice colony injected with a mouse-weight equivalent dose of all vaccines that are administered to infants in their first 18 months of life according to the U. S. pediatric vaccination schedule. Cytokines have been studied extensively as blood immune and inflammatory biomarkers, and their association with neurodevelopmental disorders. Given the importance of cytokines in early neurodevelopment, we aimed to investigate the potential post-administration effects of the U. S. pediatric vaccines on circulatory cytokines in a mouse model. In the current study, cytokines have been assayed at early and late time points in mice vaccinated early in postnatal life and compared with placebo controls. Materials and methods Newborn mouse pups were divided into three groups: i) vaccine (V1), ii) vaccine × 3 (V3) and iii) placebo control. V1 group was injected with mouse weight-equivalent of the current U. S. pediatric vaccine schedule. V3 group was injected with same vaccines but at triple the dose and the placebo control was injected with saline. Pups were also divided according to the sampling age into two main groups: acute- and chronic-phase group. Blood samples were collected at postnatal day (PND) 23, two days following vaccine schedule for the acute-phase group or at 67 weeks post-vaccination for the chronic-phase groups. Fifteen cytokines were analyzed: GM-CSF, IFN-γ, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12p70, IL-13, IL-17A, MCP-1, TNF-α, and VEGF-A. Wilcoxon Rank Sum test or unpaired Student's t-test was performed where applicable. Results IL-5 levels in plasma were significantly elevated in the V1 and V3 group compared with the control only in the acute-phase group. The elevation of IL-5 levels in the two vaccine groups were significant irrespective of whether the sexes were combined or analyzed separately. Other cytokines (VEGF-A, TNF-α, IL-10, MCP-1, GM-CSF, IL-6, and IL-13) were also impacted, although to a lesser extent and in a sex-dependent manner. In the acute-phase group, females showed a significant increase in IL-10 and MCP-1 levels and a decrease in VEGF-A levels in both V1 and V3 group compared to controls. In the acute-phase, a significant increase in MCP-1 levels in V3 group and CM-CSF levels in V1 and V3 group and decrease in TNF-α levels in V1 group were observed in treated males as compared with controls. In chronic-phase females, levels of VEGF-A in V1 and V3 group, TNF-α in V3 group, and IL-13 in V1 group were significantly decreased in contrast with controls. In chronic-phase males, TNF-α levels were significantly increased in V1 group and IL-6 levels decreased in V3 group in comparison to controls. The changes in levels of most tested cytokines were altered between the early and the late postnatal assays. Conclusions IL-5 levels significantly increased in the acute-phase of the treatment in the plasma of both sexes that were subjected to V1 and V3 injections. These increases had diminished by the second test assayed at week 67. These results suggest that a profound, albeit transient, effect on cytokine levels may be induced by the whole vaccine administration supporting our recently published observations regarding the behavioral abnormalities in the same mice. These observations support the view that the administration of whole pediatric vaccines in a neonatal period may impact at least short-term CNS functions in mice.
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Affiliation(s)
- S C Bairwa
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - C A Shaw
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada.,Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada.,Program in Experimental Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - M Kuo
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - J Yoo
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - L Tomljenovic
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - H Eidi
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada.,French Agency for Veterinary Medicinal Products (ANMV) - French Agency for Food, Environmental and Occupational Health Safety (ANSES), Fougères, France
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Navazani P, Vaseghi S, Hashemi M, Shafaati MR, Nasehi M. Effects of Treadmill Exercise on the Expression Level of BAX, BAD, BCL-2, BCL-XL, TFAM, and PGC-1α in the Hippocampus of Thimerosal-Treated Rats. Neurotox Res 2021; 39:1274-1284. [PMID: 33939098 DOI: 10.1007/s12640-021-00370-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/10/2021] [Accepted: 04/26/2021] [Indexed: 01/11/2023]
Abstract
Thimerosal (THIM) induces neurotoxic changes including neuronal death and releases apoptosis inducing factors from mitochondria to cytosol. THIM alters the expression level of factors involved in apoptosis. On the other hand, the anti-apoptotic effects of exercise have been reported. In this study, we aimed to discover the effect of three protocols of treadmill exercise on the expression level of mitochondrial transcription factor A (TFAM), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), BCL-2-associated death (BAD), BCL-2-associated X (BAX), BCL-XL, and BCL-2 (a pro-survival BCL-2 protein) in the hippocampus of control and THIM-exposed rats. Male Wistar rats were used in this research. Real-time PCR was applied to assess genes expression. The results showed that THIM increased the expression of pro-apoptotic factors (BAD and BAX), decreased the expression of anti-apoptotic factors (BCL-2 and BCL-XL), and decreased the expression of factors involved in mitochondrial biogenesis (TFAM and PGC-1α). Treadmill exercise protocols reversed the effect of THIM on all genes. In addition, treadmill exercise protocols decreased the expression of BAD and BAX, increased the expression of BCL-2, and increased the expression of TFAM and PGC-1α in control rats. In conclusion, THIM induced a pro-apoptotic effect and disturbed mitochondrial biogenesis and stability, whereas treadmill exercise reversed these effects.
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Affiliation(s)
- Pouria Navazani
- Department of Genetics, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Salar Vaseghi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.,Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran
| | - Mehrdad Hashemi
- Department of Genetics, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad-Reza Shafaati
- Department of Cellular and Molecular Biology, Faculty of Basic Sciences, Hamadan Branch, Islamic Azad University, Hamadan, Iran
| | - Mohammad Nasehi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
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Branco V, Aschner M, Carvalho C. Neurotoxicity of mercury: an old issue with contemporary significance. ADVANCES IN NEUROTOXICOLOGY 2021; 5:239-262. [PMID: 34263092 PMCID: PMC8276940 DOI: 10.1016/bs.ant.2021.01.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Mercury exerts a variety of toxic effects, depending on the specific compound and route of exposure. However, neurotoxicity in virtue of its consequence to health causes the greatest concern for toxicologists. This is particularly true regarding fetal development, where neurotoxic effects are much more severe than in adults, and the toxicity threshold is lower. Here, we review the major concepts regarding the neurotoxicity of mercury compounds (mercury vapor; methylmercury and ethylmercury), from exposure routes to toxicokinetic particularities leading to brain deposition and the development of neurotoxic effects. Albeit research on the neurotoxicity of mercury compounds has significantly advanced from the second half of the twentieth century onwards, several grey areas regarding the mechanism of toxicity still exist. Thus, we emphasize research advances during the last two decades concerning the molecular interactions of mercury which cause neurotoxic effects. Highlights include the disruption of glutamate signaling and excitotoxicity resulting from exposure to mercury and the interaction with redox active residues such as cysteines and selenocysteines which are the premise accounting for the disruption of redox homeostasis caused by mercurials. We also address how immunotoxic effects at the CNS, namely microglia and astrocyte activation modulate developmental neurotoxicity, a major topic in contemporary research.
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Affiliation(s)
- Vasco Branco
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, USA
| | - Cristina Carvalho
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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Kern JK, Geier DA, Mehta JA, Homme KG, Geier MR. Mercury as a hapten: A review of the role of toxicant-induced brain autoantibodies in autism and possible treatment considerations. J Trace Elem Med Biol 2020; 62:126504. [PMID: 32534375 DOI: 10.1016/j.jtemb.2020.126504] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/28/2020] [Accepted: 03/18/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND Mercury has many direct and well-recognized neurotoxic effects. However, its immune effects causing secondary neurotoxicity are less well-recognized. Mercury exposure can induce immunologic changes in the brain indicative of autoimmune dysfunction, including the production of highly specific brain autoantibodies. Mercury, and in particular, Thimerosal, can combine with a larger carrier, such as an endogenous protein, thereby acting as a hapten, and this new molecule can then elicit the production of antibodies. METHODS A comprehensive search using PubMed and Google Scholar for original studies and reviews related to autism, mercury, autoantibodies, autoimmune dysfunction, and haptens was undertaken. All articles providing relevant information from 1985 to date were examined. Twenty-three studies were identified showing autoantibodies in the brains of individuals diagnosed with autism and all were included and discussed in this review. RESULTS Research shows mercury exposure can result in an autoimmune reaction that may be causal or contributory to autism, especially in children with a family history of autoimmunity. The autoimmune pathogenesis in autism is demonstrated by the presence of brain autoantibodies (neuroantibodies), which include autoantibodies to: (1) human neuronal progenitor cells; (2) myelin basic protein (MBP); (3) neuron-axon filament protein (NAFP); (4) brain endothelial cells; (5) serotonin receptors; (6) glial fibrillary acidic protein (GFAP); (7) brain derived neurotrophic factor (BDNF); (8) myelin associated glycoprotein (MAG); and (9) various brain proteins in the cerebellum, hypothalamus, prefrontal cortex, cingulate gyrus, caudate putamen, cerebral cortex and caudate nucleus. CONCLUSION Recent evidence suggests a relationship between mercury exposure and brain autoantibodies in individuals diagnosed with autism. Moreover, brain autoantibody levels in autism are found to correlate with both autism severity and blood mercury levels. Treatments to reduce mercury levels and/or brain autoantibody formation should be considered in autism.
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Affiliation(s)
- Janet K Kern
- Institute of Chronic Illnesses, Inc., Silver Spring, MD, USA; CoMeD, Inc., Silver Spring, MD, USA; CONEM US Autism Research Group, Allen, TX, USA.
| | - David A Geier
- Institute of Chronic Illnesses, Inc., Silver Spring, MD, USA; CoMeD, Inc., Silver Spring, MD, USA
| | - Jyutika A Mehta
- Texas Woman's University, Department of Communication Sciences and Disorders, Denton, TX, USA
| | - Kristin G Homme
- CoMeD, Inc., Silver Spring, MD, USA; International Academy of Oral Medicine and Toxicology, Champions Gate, FL, USA
| | - Mark R Geier
- Institute of Chronic Illnesses, Inc., Silver Spring, MD, USA; CoMeD, Inc., Silver Spring, MD, USA
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9
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An isolated retrograde-perfused newborn mouse heart preparation. MethodsX 2020; 7:101058. [PMID: 32983923 PMCID: PMC7492986 DOI: 10.1016/j.mex.2020.101058] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/02/2020] [Indexed: 11/24/2022] Open
Abstract
The Langendorff-perfused model is a powerful tool to study biological responses in the isolated heart in the absence of confounders. The model has been adapted recently to enable study of the isolated mouse heart and the effects of genetic manipulation. Unfortunately, the small size and fragility of the mouse heart pose significant challenges, limiting application of the Langendorff model to the study of adult mice. Cardiac development is a complex and dynamic process that is incompletely understood. Thus, establishing an isolated-perfused heart model in the newborn mouse would be an important and necessary advance. Here we present a method to successfully cannulate and perfuse the isolated newborn murine heart. We describe the basic and fundamental physiological characteristics of the ex-vivo retrograde-perfused beating neonatal heart in wild-type C57Bl/6 male mice. Our approach will enable future study of the physiological and pharmacological responses of the isolated immature murine heart to enhance knowledge of how developmental cardiac biology impacts health and disease.The Langendorff model is a powerful tool to study the heart without confounders. An isolated-perfused newborn murine heart model has yet to be established. We demonstrate the first successful isolated neonatal murine heart preparation.
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10
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Eidi H, Yoo J, Bairwa SC, Kuo M, Sayre EC, Tomljenovic L, Shaw CA. Early postnatal injections of whole vaccines compared to placebo controls: Differential behavioural outcomes in mice. J Inorg Biochem 2020; 212:111200. [PMID: 33039918 DOI: 10.1016/j.jinorgbio.2020.111200] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/24/2020] [Accepted: 07/19/2020] [Indexed: 12/24/2022]
Abstract
The present study was designed to evaluate the possible effects of the paediatric vaccination schedule in the United States on the central nervous system in a murine model. We compared the impact of treatment with the whole vaccines versus true placebo control. Seventy-six pups were divided into three groups: two vaccinated groups and unvaccinated control. The two vaccinated groups were treated between 7 and 21 post-natal days either with one or three times of the vaccine doses per body weight as used in children between newborn and eighteen months of age. The post-vaccination development, neuromotor behaviours and neurobehavioural abnormalities (NBAs) were evaluated in all mouse groups during the 67 post-natal weeks of mouse age. Mouse body weight was affected only in the vaccinated females compared to males and control. Some NBAs such as decreased sociability, increased anxiety-like behaviours, and alteration of visual-spatial learning and memory were observed in vaccinated male and female mice compared to controls. The present study also shows a slower acquisition of some neonatal reflexes in vaccinated female mice compared to vaccinated males and controls. The observed neurodevelopmental alterations did not show a linear relationship with vaccine dose, suggesting that the single dose gave a saturated response. The outcomes seemed to be sex-dependent and transient with age.
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Affiliation(s)
- Housam Eidi
- Neural Dynamics Research Group, Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada; French agency for veterinary medicinal products (ANMV) - French agency for food, environmental and occupational health safety (ANSES), Fougères, France.
| | - Janice Yoo
- Neural Dynamics Research Group, Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Suresh C Bairwa
- Neural Dynamics Research Group, Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael Kuo
- Neural Dynamics Research Group, Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Lucija Tomljenovic
- Neural Dynamics Research Group, Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christopher A Shaw
- Neural Dynamics Research Group, Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada; Program in Experimental Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
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Abdelzaher LA, Hussein OA, Ashry IEM. The Novel Potential Therapeutic Utility of Montelukast in Alleviating Autistic Behavior Induced by Early Postnatal Administration of Thimerosal in Mice. Cell Mol Neurobiol 2020; 41:129-150. [PMID: 32303879 DOI: 10.1007/s10571-020-00841-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Accepted: 04/01/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIM: Thimerosal (THIM) is a mercury-containing preservative widely used in many biological and medical products including many vaccines. It has been accused of being a possible etiological factor for some neurodevelopmental disorders such as autistic spectrum disorders (ASDs). In our study, the potential therapeutic effect of montelukast, a leukotriene receptor antagonist used to treat seasonal allergies and asthma, on THIM mice model (ASDs model) was examined. METHODOLOGY Newborn mice were randomly distributed into three groups: (Group 1) Control (Cont.) group received saline injections. (Group 2) THIM-treated (THIM) group received THIM intramuscular (IM) at a dose of 3000 μg Hg/kg on postnatal days 7, 9, 11, and 15. (Group 3) Montelukast-treated (Monte) group received THIM followed by montelukast sodium (10 mg/kg/day) intraperitoneal (IP) for 3 weeks. Mice were evaluated for growth development, social interactions, anxiety, locomotor activity, and cognitive function. Brain histopathology, alpha 7 nicotinic acetylcholine receptors (α7nAChRs), nuclear factor kappa B p65 (NF-κB p65), apoptotic factor (Bax), and brain injury markers were evaluated as well. RESULTS THIIM significantly impaired social activity and growth development. Montelukast mitigated THIM-induced social deficit probably through α7nAChRs upregulation, NF-κB p65, Bax, and brain injury markers downregulation, thus suppressing THIM-induced neuronal toxicity and inflammation. CONCLUSION Neonatal exposure to THIM can induce growth retardation and abnormal social interactions similar to those observed in ASDs. Some of these abnormalities could be ameliorated by montelukast via upregulation of α7nAChRs that inhibited NF-κB activation and significant suppression of neuronal injury and the associated apoptosis.
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Affiliation(s)
- Lobna A Abdelzaher
- Department of Pharmacology, Faculty of Medicine, Assiut University, Assiut, Egypt.
| | - Ola A Hussein
- Department of Histology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - I E M Ashry
- Department of Pharmacology, Faculty of Medicine, Assiut University, Assiut, Egypt
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Noshadian M, Namvarpour Z, Amini A, Raoofi A, Atabati H, Sadeghi Y, Aliaghaei A, Abdollahifar MA. Alpha lipoic acid ameliorates THIM-induced prefrontal cell loss and abnormal enzymatically contents in the developing rat. J Chem Neuroanat 2019; 103:101727. [PMID: 31740419 DOI: 10.1016/j.jchemneu.2019.101727] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/12/2019] [Accepted: 11/14/2019] [Indexed: 12/13/2022]
Abstract
Thimerosal (THIM) is a common preservative used in many pharmaceutical drugs, vaccines, cosmetics and many other products. Today, it was somewhat clear that Thimerosal (THIM) is a neurotoxicant preservative. We aimed to use of a suitable agent for preventing of THIM side effects on brain. Therefore, in this research, the protective effects of Alpha Lipoic Acid (ALA), against THIM-induced brain cell loss, changes in neuroimmune cell and enzymatically contents were examined. Male Wistar rats (n = 60) were randomly distributed into five groups: 1- THIM group; this group received THIM at dose of 300 μg /kg on 7, 9, 11, 15 days after birth 2- ALA group; received ALA (20 mg/kg) in the same order. 3- THIM & ALA group; this group received ALA in the same dose, 30 min before THIM administration.4& 5; Saline and ALA vehicle groups were also included. At 56th postnatal day, samples of the prefrontal cortex were collected and prepared for stereological, immune-histochemical, and enzymatic evaluations. The result showed that ALA, prevents the adverse effects of THIM on brain cell loss, abnormal changes in neuroimmune cells (p < 0.05), prefrontal cortex volume (p < 0.05), and the glutathione content of prefrontal cortex (p < 0.05). In conclusion, neonatal exposure to THIM can induce abnormal alterations in neuroimmune cells and brain cell density as well as prefrontal cortex volume & glutathione content, and ALA can ameliorate these abnormalities.
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Affiliation(s)
- Mehrazin Noshadian
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Abdollah Amini
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Amir Raoofi
- Cellular and Molecular Research Center,Department of Anatomical Sciences, School of Medicine, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Hadi Atabati
- Department of Immunology and Biology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Yousef Sadeghi
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abass Aliaghaei
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Modammad-Amin Abdollahifar
- Department of Biology and Anatomical Sciences, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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13
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Hasegawa Y, Curtis B, Yutuc V, Rulien M, Morrisroe K, Watkins K, Ferrier C, English C, Hewitson L, Slupsky CM. Microbial structure and function in infant and juvenile rhesus macaques are primarily affected by age, not vaccination status. Sci Rep 2018; 8:15867. [PMID: 30367140 PMCID: PMC6203732 DOI: 10.1038/s41598-018-34019-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 10/06/2018] [Indexed: 01/12/2023] Open
Abstract
Although thimerosal, an ethylmercury-based preservative, has been removed from most pediatric vaccines in the United States, some multidose vaccines, such as influenza vaccines, still contain thimerosal. Considering that a growing number of studies indicate involvement of the gut microbiome in infant immune development and vaccine responses, it is important to elucidate the impact of pediatric vaccines, including thimerosal-containing vaccines, on gut microbial structure and function. Here, a non-human primate model was utilized to assess how two vaccine schedules affect the gut microbiome in infants (5-9 days old) and juveniles (77-88 weeks old) through 16S ribosomal RNA sequencing and metabolomics analyses of the fecal samples. Two treatment groups (n = 12/group) followed either the vaccine schedule that was in place during the 1990s (intensive exposure to thimerosal) or an expanded schedule administered in 2008 (prenatal and postnatal exposure to thimerosal mainly via influenza vaccines), and were compared with a control group (n = 16) that received saline injections. The primary impact on gut microbial structure and function was age. Although a few statistically significant impacts of the two common pediatric vaccine schedules were observed when confounding factors were considered, the magnitude of the differences was small, and appeared to be positive with vaccination.
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Affiliation(s)
- Yu Hasegawa
- Department of Food Science and Technology, University of California Davis, Davis, California, USA
| | - Britni Curtis
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Vernon Yutuc
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Megan Rulien
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Kelly Morrisroe
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Kristin Watkins
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Clayton Ferrier
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Chris English
- Infant Primate Research Laboratory (IPRL), Washington National Primate Research Center, and Center on Human Development and Disability (CHDD), Seattle, Washington, USA
| | - Laura Hewitson
- The Johnson Center for Child Health and Development, Austin, Texas, USA.
| | - Carolyn M Slupsky
- Department of Food Science and Technology, University of California Davis, Davis, California, USA.
- Department of Nutrition, University of California Davis, Davis, California, USA.
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Afsordeh K, Sadeghi Y, Amini A, Namvarpour Z, Abdollahifar MA, Abbaszadeh HA, Aliaghaei A. Alterations of neuroimmune cell density and pro-inflammatory cytokines in response to thimerosal in prefrontal lobe of male rats. Drug Chem Toxicol 2018; 42:176-186. [DOI: 10.1080/01480545.2018.1465949] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Kobra Afsordeh
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Yousef Sadeghi
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abdollah Amini
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Mohammad-Amin Abdollahifar
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hojjat-Allah Abbaszadeh
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Hearing Disorders Research Center, Loghman Hakim Medical Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abass Aliaghaei
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Namvarpour Z, Nasehi M, Amini A, Zarrindast MR. Protective role of alpha-lipoic acid in impairments of social and stereotyped behaviors induced by early postnatal administration of thimerosal in male rat. Neurotoxicol Teratol 2018; 67:1-9. [PMID: 29481853 DOI: 10.1016/j.ntt.2018.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 02/20/2018] [Accepted: 02/22/2018] [Indexed: 12/20/2022]
Abstract
Aim Thimerosal, a mercury-containing preservative has been widely used in a number of biological and drug products, including many vaccines, and has been studied as a possible etiological factor for some neurodevelopmental disabilities. Here, the protective effects of Alpha Lipoic Acid (ALA), an organosulfur compound derived from Octanoic Acid, on Thimerosal-induced behavioral abnormalities in rat were examined. METHODS 108 male Wistar rats were divided into three cohorts and treated as follows: 1) Thimerosal at different doses (30, 300, or 3000 μg Hg/kg) in four i.m. injections on 7, 9, 11, 15postnatal days. 2) ALA (at doses of 5, 10 and 20 mg/kg), following the same order; 3) single dose of Thimerosal (3000 μg Hg/kg) plus ALA at different doses (5, 10 or 20 mg/kg), by the previously described method. A saline treated control group and a ALA vehicle control (0.1% NaOH) were also included. At 5 and 8 weeks after birth, rats were evaluated with behavioral tests, to assess locomotor activity, social interactions and stereotyped behaviors, respectively. RESULTS The data showed that Thimerosal at all doses (30, 300 and 3000 μg Hg/kg) significantly impacted locomotor activity. Thimerosal at doses of 300 and 3000 but not 30 μg Hg/kg impaired social and stereotyped behaviors. In contrast, ALA (at doses of 5, 10 and 20 mg/kg) did not alter behaviors by itself, at doses of 20 mg/kg, it reduced social interaction deficits induced by the highest dose of Thimerosal (3000 μg Hg/kg). Moreover, ALA, at all doses prevented the adverse effects of Thimerosal on stereotyped behaviors. CONCLUSIONS the results of this preclinical study, consistent with previous studies on mice and rats, reveals that neonatal dose-dependent exposure to Thimerosal mimicking the childhood vaccine schedule can induce abnormal social interactions and stereotyped behaviors similar to those observed in neurodevelopmental disorders such as autism, and, for the first time, revealed that these abnormalities may be ameliorated by ALA. This indicates that ALA may protect against mercurial-induced abnormal behaviors.
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Affiliation(s)
| | - Mohammad Nasehi
- Institute for Cognitive Science Studies (ICSS), Tehran, Iran; Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran.
| | - Abdollah Amini
- Department of Biology and Anatomy, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad-Reza Zarrindast
- Institute for Cognitive Science Studies (ICSS), Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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Pantaleão TU, Ferreira ACF, Santos MCS, Figueiredo ÁSP, Louzada RAN, Rosenthal D, Carvalho DP, Corrêa da Costa VM. Effect of thimerosal on thyroid hormones metabolism in rats. Endocr Connect 2017; 6:741-747. [PMID: 29101249 PMCID: PMC5670274 DOI: 10.1530/ec-17-0220] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 10/05/2017] [Indexed: 01/09/2023]
Abstract
Mercury seems to exert an inhibitory effect on deiodinases, but there are few studies using Thimerosal (TM) as the mercury source. We aimed to elucidate the effect of TM on thyroid hormones peripheral metabolism. Adult Wistar female rats received 0.25 µg or 250 µg TM/100 g BW, IM, twice a week, for a month. We evaluated serum total T3 and T4, D1 activity using 125I-rT3 as tracer, and D2 activity using 125I-T4 NADPH oxidase activity was measured by Amplex-red/HRP method and mRNA levels by real time PCR. Serum T4 was increased and T3 decreased by the greatest dose of TM. Even though D1 activity in pituitary and kidney was reduced by the highest dose of TM, hepatic D1 activity and D1 mRNA levels remained unchanged. D2 activity was also significantly decreased by the highest dose of TM in all CNS samples tested, except cerebellum, but D2 mRNA was unaltered. mRNA levels of the tested NADPH oxidases were not affected by TM and NADPH oxidase activity was either unaltered or decreased. Our results indicate that TM might directly interact with deiodinases, inhibiting their activity probably by binding to their selenium catalytic site, without changes in enzyme expression.
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Affiliation(s)
- Thiago U Pantaleão
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Andrea C F Ferreira
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- NUMPEXPólo de Xerém, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria C S Santos
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Álvaro S P Figueiredo
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ruy A N Louzada
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Doris Rosenthal
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Denise P Carvalho
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vânia M Corrêa da Costa
- Laboratório de Fisiologia Endócrina Doris RosenthalInstituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Li D, Tomljenovic L, Li Y, Shaw CA. RETRACTED: Subcutaneous injections of aluminum at vaccine adjuvant levels activate innate immune genes in mouse brain that are homologous with biomarkers of autism. J Inorg Biochem 2017; 177:39-54. [PMID: 28923356 DOI: 10.1016/j.jinorgbio.2017.08.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 01/11/2023]
Affiliation(s)
- Dan Li
- Dept. of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Lucija Tomljenovic
- Dept. of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Yongling Li
- Dept. of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christopher A Shaw
- Dept. of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada; Program in Experimental Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada.
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18
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Geier D, Geier MR. Neurodevelopmental Disorders Following Thimerosal-Containing Childhood Immunizations: A Follow-Up Analysis. Int J Toxicol 2016; 23:369-76. [PMID: 15764492 DOI: 10.1080/10915810490902038] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The authors previously published the first epidemiological study from the United States associating thimerosal from childhood vaccines with neurodevelopmental disorders (NDs) based upon assessment of the Vaccine Adverse Event Reporting System (VAERS). A number of years have gone by since their previous analysis of the VAERS. The present study was undertaken to determine whether the previously observed effect between thimerosal-containing childhood vaccines and NDs are still apparent in the VAERS as children have had a chance to further mature and potentially be diagnosed with additional NDs. In the present study, a cohort of children receiving thimerosal-containing diphtheria-tetanus-acellular pertussis (DTaP) vaccines in comparison to a cohort of children receiving thimerosal-free DTaP vaccines administered from 1997 through 2000 based upon an assessment of adverse events reported to the VAERS were evaluated. It was determined that there were significantly increased odds ratios (ORs) for autism (OR = 1.8, p < .05), mental retardation (OR = 2.6, p < .002), speech disorder (OR = 2.1, p <.02), personality disorders (OR=2.6, p <.01), and thinking abnormality (OR=8.2, p <.01) adverse events reported to the VAERS following thimerosal-containing DTaP vaccines in comparison to thimerosal-free DTaP vaccines. Potential confounders and reporting biases were found to be minimal in this assessment of the VAERS. It was observed, even though the media has reported a potential association between autism and thimerosal exposure, that the other NDs analyzed in this assessment of the VAERS had significantly higher ORs than autism following thimerosal-containing DTaP vaccines in comparison to thimerosal-free DTaP vaccines. The present study provides additional epidemiological evidence supporting previous epidemiological, clinical and experimental evidence that administration of thimerosal-containing vaccines in the United States resulted in a significant number of children developing NDs.
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Guida N, Laudati G, Mascolo L, Cuomo O, Anzilotti S, Sirabella R, Santopaolo M, Galgani M, Montuori P, Di Renzo G, Canzoniero LMT, Formisano L. MC1568 Inhibits Thimerosal-Induced Apoptotic Cell Death by Preventing HDAC4 Up-Regulation in Neuronal Cells and in Rat Prefrontal Cortex. Toxicol Sci 2016; 154:227-240. [PMID: 27660204 DOI: 10.1093/toxsci/kfw157] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Ethylmercury thiosalicylate (thimerosal) is an organic mercury-based compound commonly used as an antimicrobial preservative that has been found to be neurotoxic. In contrast, histone deacetylases (HDACs) inhibition has been found to be neuroprotective against several environmental contaminants, such as polychlorinated biphenyls, di-2-ethylhexyl phthalate, and methylmercury. The aim of this study was to investigate the effect of HDAC inhibition on thimerosal-induced neurotoxicity in neuroblastoma cells and cortical neurons. Interestingly, we found that thimerosal, at 0.5 μM in SH-SY5Y cells and at 1 μM in neurons, caused cell death by activation of apoptosis, which was prevented by the HDAC class IIA inhibitor MC1568 but not the class I inhibitor MS275. Furthermore, thimerosal specifically increased HDAC4 protein expression but not that of HDACs 5, 6, 7, and 9. Western blot analysis revealed that MC1568 prevented thimerosal-induced HDAC4 increase. In addition, both HDAC4 knocking-down and MC1568 inhibited thimerosal-induced cell death in SH-SY5Y cells and cortical neurons. Importantly, intramuscular injection of 12 μg/kg thimerosal on postnatal days 7, 9, 11, and 15 increased HDAC4 levels in the prefrontal cortex (PFC), which decreased histone H4 acetylation in infant male rats, in parallel increased motor activity changes. In addition, coadministration of 40 mg/kg MC1568 (intraperitoneal injection) moderated the HDAC4 increase which reduced histone H4 deacetylation and caspase-3 cleavage in the PFC. Finally, open-field testing showed that thimerosal-induced motor activity changes are reduced by MC1568. These findings indicate that HDAC4 regulates thimerosal-induced cell death in neurons and that treatment with MC1568 prevents thimerosal-induced activation of caspase-3 in the rat PFC.
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Affiliation(s)
| | - Giusy Laudati
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy
| | - Luigi Mascolo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy
| | - Ornella Cuomo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy
| | | | - Rossana Sirabella
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy
| | - Marianna Santopaolo
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II" Napoli, Naples 80131, Italy
| | - Mario Galgani
- Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), Napoli 80131, Italy
| | - Paolo Montuori
- Department of Preventive Medical Sciences, University Federico II, Via Pansini 5, Naples, 80131, Italy
| | - Gianfranco Di Renzo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy
| | - Lorella M T Canzoniero
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy.,Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento 82100, Italy
| | - Luigi Formisano
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, "Federico II" University of Naples, Naples 80131, Italy .,Division of Pharmacology, Department of Science and Technology, University of Sannio, Benevento 82100, Italy
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Geier DA, Kern JK, Hooker BS, King PG, Sykes LK, Geier MR. A longitudinal cohort study of the relationship between Thimerosal-containing hepatitis B vaccination and specific delays in development in the United States: Assessment of attributable risk and lifetime care costs. J Epidemiol Glob Health 2015; 6:105-18. [PMID: 26166425 PMCID: PMC7320444 DOI: 10.1016/j.jegh.2015.06.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 05/04/2015] [Accepted: 06/01/2015] [Indexed: 12/15/2022] Open
Abstract
Epidemiological evidence suggests a link between mercury (Hg) exposure from Thimerosal-containing vaccines and specific delays in development. A hypothesis-testing longitudinal cohort study (n = 49,835) using medical records in the Vaccine Safety Datalink (VSD) was undertaken to evaluate the relationship between exposure to Hg from Thimerosal-containing hepatitis B vaccines (T-HBVs) administered at specific intervals in the first 6 months of life and specific delays in development [International Classification of Disease, 9th revision (ICD-9): 315.xx] among children born between 1991 and 1994 and continuously enrolled from birth for at least 5.81 years. Infants receiving increased Hg doses from T-HBVs administered within the first month, the first 2 months, and the first 6 months of life were significantly more likely to be diagnosed with specific delays in development than infants receiving no Hg doses from T-HBVs. During the decade in which T-HBVs were routinely recommended and administered to US infants (1991–2001), an estimated 0.5–1 million additional US children were diagnosed with specific delays in development as a consequence of 25 μg or 37.5 μg organic Hg from T-HBVs administered within the first 6 months of life. The resulting lifetime costs to the United States may exceed $1 trillion.
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Affiliation(s)
- David A Geier
- Institute of Chronic Illnesses, Inc, Silver Spring, MD, USA
| | - Janet K Kern
- Institute of Chronic Illnesses, Inc, Silver Spring, MD, USA.
| | - Brian S Hooker
- Biology Department, Simpson University, Redding, CA, USA
| | | | | | - Mark R Geier
- Institute of Chronic Illnesses, Inc, Silver Spring, MD, USA
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Yepsen O, Contreras D, Santander P, Yáñez J, Mansilla HD, Amarasiriwardena D. Photocatalytic degradation of thimerosal in human vaccine's residues and mercury speciation of degradation by-products. Microchem J 2015. [DOI: 10.1016/j.microc.2015.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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22
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Curtis B, Liberato N, Rulien M, Morrisroe K, Kenney C, Yutuc V, Ferrier C, Marti CN, Mandell D, Burbacher TM, Sackett GP, Hewitson L. Examination of the safety of pediatric vaccine schedules in a non-human primate model: assessments of neurodevelopment, learning, and social behavior. ENVIRONMENTAL HEALTH PERSPECTIVES 2015; 123:579-589. [PMID: 25690930 PMCID: PMC4455585 DOI: 10.1289/ehp.1408257] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 02/12/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND In the 1990s, the mercury-based preservative thimerosal was used in most pediatric vaccines. Although there are currently only two thimerosal-containing vaccines (TCVs) recommended for pediatric use, parental perceptions that vaccines pose safety concerns are affecting vaccination rates, particularly in light of the much expanded and more complex schedule in place today. OBJECTIVES The objective of this study was to examine the safety of pediatric vaccine schedules in a non-human primate model. METHODS We administered vaccines to six groups of infant male rhesus macaques (n = 12-16/group) using a standardized thimerosal dose where appropriate. Study groups included the recommended 1990s Pediatric vaccine schedule, an accelerated 1990s Primate schedule with or without the measles-mumps-rubella (MMR) vaccine, the MMR vaccine only, and the expanded 2008 schedule. We administered saline injections to age-matched control animals (n = 16). Infant development was assessed from birth to 12 months of age by examining the acquisition of neonatal reflexes, the development of object concept permanence (OCP), computerized tests of discrimination learning, and infant social behavior. Data were analyzed using analysis of variance, multilevel modeling, and survival analyses, where appropriate. RESULTS We observed no group differences in the acquisition of OCP. During discrimination learning, animals receiving TCVs had improved performance on reversal testing, although some of these same animals showed poorer performance in subsequent learning-set testing. Analysis of social and nonsocial behaviors identified few instances of negative behaviors across the entire infancy period. Although some group differences in specific behaviors were reported at 2 months of age, by 12 months all infants, irrespective of vaccination status, had developed the typical repertoire of macaque behaviors. CONCLUSIONS This comprehensive 5-year case-control study, which closely examined the effects of pediatric vaccines on early primate development, provided no consistent evidence of neurodevelopmental deficits or aberrant behavior in vaccinated animals.
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Affiliation(s)
- Britni Curtis
- Infant Primate Research Laboratory, Washington National Primate Research Center, Seattle, Washington, USA
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Macedoni-Lukšič M, Gosar D, Bjørklund G, Oražem J, Kodrič J, Lešnik-Musek P, Zupančič M, France-Štiglic A, Sešek-Briški A, Neubauer D, Osredkar J. Levels of metals in the blood and specific porphyrins in the urine in children with autism spectrum disorders. Biol Trace Elem Res 2015; 163:2-10. [PMID: 25234471 DOI: 10.1007/s12011-014-0121-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 09/03/2014] [Indexed: 12/27/2022]
Abstract
The aim of the present study was to determine the levels of metals in blood (zinc (Zn), copper (Cu), aluminium (Al), lead (Pb) and mercury (Hg)), as well as the specific porphyrin levels in the urine of patients with autism spectrum disorder (ASD) compared with patients with other neurological disorders. The study was performed in a group of children with ASD (N = 52, average age = 6.2 years) and a control group of children with other neurological disorders (N = 22, average age = 6.6 years), matched in terms of intellectual abilities (Mann-Whitney U = 565.0, p = 0.595). Measurement of metals in blood was performed by atomic absorption spectrometry, while the HPLC method via a fluorescence detector was used to test urinary porphyrin levels. Results were compared across groups using a multivariate analysis of covariance (MANCOVA). In addition, a generalized linear model was used to establish the impact of group membership on the blood Cu/Zn ratio. In terms of blood levels of metals, no significant difference between the groups was found. However, compared to the control group, ASD group had significantly elevated blood Cu/Zn ratio (Wald χ (2) = 6.6, df = 1, p = 0.010). Additionally, no significant difference between the groups was found in terms of uroporphyrin I, heptacarboxyporphyrin I, hexacarboxyporphyrin and pentacarboxyporphyrin I. However, the levels of coproporphyrin I and coproporphyrin III were lower in the ASD group compared to the controls. Due to observed higher Cu/Zn ratio, it is suggested to test blood levels of Zn and Cu in all autistic children and give them a Zn supplement if needed.
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Geier DA, Kern JK, Hooker BS, King PG, Sykes LK, Geier MR. Thimerosal-containing hepatitis B vaccination and the risk for diagnosed specific delays in development in the United States: a case-control study in the vaccine safety datalink. NORTH AMERICAN JOURNAL OF MEDICAL SCIENCES 2014; 6:519-31. [PMID: 25489565 PMCID: PMC4215490 DOI: 10.4103/1947-2714.143284] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background: Within the first 3 years of life, the brain develops rapidly. Its development is characterized by critical developmental periods for speech, vision, hearing, language, balance, etc.; and alteration in any of the processes occurring in those critical periods can lead to specific delays in development. Aims: The present study evaluated the potential toxic effects of organic-mercury exposure from Thimerosal (49.55% mercury by weight) in childhood vaccines and its hypothesized possible relationship with specific delays in development. Materials and Methods: A hypothesis testing case-control study was undertaken to evaluate the relationship between exposure to Thimerosal-containing hepatitis B vaccines administered at specific intervals in the first 6 months among cases diagnosed with specific delays in development and controls born between 1991-2000, utilizing data in the Vaccine Safety Datalink database. Results: Cases were significantly more likely than controls to have received increased organic-mercury from Thimerosal-containing hepatitis B vaccine administered in the first, second, and sixth month of life. Conclusion: Though routine childhood vaccination may be an important public health tool to reduce the morbidity and mortality associated with infectious diseases, the present study supports an association between increasing organic-mercury exposure from Thimerosal-containing childhood vaccines and the subsequent risk of specific delays in development among males and females.
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Affiliation(s)
- David A Geier
- Institute of Chronic Illnesses, Inc, Silver Spring, Maryland, USA
| | - Janet K Kern
- Institute of Chronic Illnesses, Inc, Silver Spring, Maryland, USA ; Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Brian S Hooker
- Biology Department, Simpson University, Redding, California, USA
| | | | | | - Mark R Geier
- Institute of Chronic Illnesses, Inc, Silver Spring, Maryland, USA
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Koh JY, Lim JS, Byun HR, Yoo MH. Abnormalities in the zinc-metalloprotease-BDNF axis may contribute to megalencephaly and cortical hyperconnectivity in young autism spectrum disorder patients. Mol Brain 2014; 7:64. [PMID: 25182223 PMCID: PMC4237964 DOI: 10.1186/s13041-014-0064-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 08/23/2014] [Indexed: 12/20/2022] Open
Abstract
Whereas aberrant brain connectivity is likely the core pathology of autism-spectrum disorder (ASD), studies do not agree as to whether hypo- or hyper-connectivity is the main underlying problem. Recent functional imaging studies have shown that, in most young ASD patients, cerebral cortical regions appear hyperconnected, and cortical thickness/brain size is increased. Collectively, these findings indicate that developing ASD brains may exist in an altered neurotrophic milieu. Consistently, some ASD patients, as well as some animal models of ASD, show increased levels of brain-derived neurotrophic factor (BDNF). However, how BDNF is upregulated in ASD is unknown. To address this question, we propose the novel hypothesis that a putative zinc-metalloprotease-BDNF (ZMB) axis in the forebrain plays a pivotal role in the development of hyperconnectivity and megalencephaly in ASD. We have previously demonstrated that extracellular zinc at micromolar concentrations can rapidly increase BDNF levels and phosphorylate the receptor tyrosine kinase TrkB via the activation of metalloproteases. The role of metalloproteases in ASD is still uncertain, but in fragile X syndrome, a monogenic disease with an autistic phenotype, the levels of MMP are increased. Early exposure to lipopolysaccharides (LPS) and other MMP activators such as organic mercurials also have been implicated in ASD pathogenesis. The resultant increases in BDNF levels at synapses, especially those involved in the zinc-containing, associative glutamatergic system may produce abnormal brain circuit development. Various genetic mutations that lead to ASD are also known to affect BDNF signaling: some down-regulate, and others up-regulate it. We hypothesize that, although both up- and down-regulation of BDNF may induce autism symptoms, only BDNF up-regulation is associated with the hyperconnectivity and large brain size observed in most young idiopathic ASD patients. To test this hypothesis, we propose to examine the ZMB axis in animal models of ASD. Synaptic zinc can be examined by fluorescence zinc staining. MMP activation can be measured by in situ zymography and Western blot analysis. Finally, regional levels of BDNF can be measured. Validating this hypothesis may shed light on the central pathogenic mechanism of ASD and aid in the identification of useful biomarkers and the development of preventive/therapeutic strategies.
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Affiliation(s)
- Jae-Young Koh
- Neural Injury Research Lab, Asan Institute for Life Science, University of Ulsan College of Medicine, Seoul, Korea
- Department of Neurology, University of Ulsan College of Medicine, 388-1 Poongnap-Dong Songpa-Gu, Seoul 138-736, Korea
| | - Joon Seo Lim
- Neural Injury Research Lab, Asan Institute for Life Science, University of Ulsan College of Medicine, Seoul, Korea
| | - Hyae-Ran Byun
- Neural Injury Research Lab, Asan Institute for Life Science, University of Ulsan College of Medicine, Seoul, Korea
| | - Min-Heui Yoo
- Neural Injury Research Lab, Asan Institute for Life Science, University of Ulsan College of Medicine, Seoul, Korea
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Li X, Qu F, Xie W, Wang F, Liu H, Song S, Chen T, Zhang Y, Zhu S, Wang Y, Guo C, Tang TS. Transcriptomic analyses of neurotoxic effects in mouse brain after intermittent neonatal administration of thimerosal. Toxicol Sci 2014; 139:452-65. [PMID: 24675092 DOI: 10.1093/toxsci/kfu049] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Thimerosal is a vaccine antimicrobial preservative which has long been suspected an iatrogenic factor possibly contributing to neurodevelopmental disorders including autism. The association between infant vaccine thimerosal exposure and autism remains an open question. Although thimerosal has been removed from mandatory childhood vaccines in the United States, thimerosal-preserved vaccines are still widely used outside of the United States especially in developing countries. Notably, thimerosal-containing vaccines are being given to the newborns within the first 12-24 h after birth in some countries. To examine the possible neurotoxic effects of early neonatal exposure to a higher level of thimerosal, FVB mice were subcutaneously injected with thimerosal-mercury at a dose which is 20× higher than that used for regular Chinese infant immunization during the first 4 months of life. Thimerosal-treated mice exhibited neural development delay, social interaction deficiency, and inclination of depression. Apparent neuropathological changes were also observed in adult mice neonatally treated with thimerosal. High-throughput RNA sequencing of autistic-behaved mice brains revealed the alternation of a number of canonical pathways involving neuronal development, neuronal synaptic function, and the dysregulation of endocrine system. Intriguingly, the elevation of anterior pituitary secreting hormones occurred exclusively in male but not in female thimerosal-treated mice, demonstrating for the first time the gender bias of thimerosal-mercury toxicity with regard to endocrine system. Our results indicate that higher dose of neonatal thimerosal-mercury (20× higher than that used in human) is capable of inducing long-lasting substantial dysregulation of neurodevelopment, synaptic function, and endocrine system, which could be the causal involvements of autistic-like behavior in mice.
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Affiliation(s)
- Xiaoling Li
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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Persico AM, Merelli S. Environmental Factors in the Onset of Autism Spectrum Disorder. CURRENT DEVELOPMENTAL DISORDERS REPORTS 2014. [DOI: 10.1007/s40474-013-0002-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
BACKGROUND There continues to be public concern that mercury exposure and autism spectrum disorder (ASD) may be associated. The primary source of exposure to organic mercury in humans is to methylmercury from fish consumption. We evaluated the association between prenatal methylmercury exposure and ASD phenotype in children and adolescents in the Republic of Seychelles, where fish consumption is high. METHODS We administered the Social Communication Questionnaire to parents of a cohort of 1784 children, adolescents, and young adults. The Social Responsiveness Scale was administered to teachers of 537 cohort subjects at about 10 years of age. Prenatal exposure to methylmercury was measured in maternal hair samples collected at or near the time of birth. Multivariable regression models evaluated the relationship between prenatal methylmercury exposure and ASD phenotypic scores, adjusting for relevant covariates. RESULTS The mean prenatal methylmercury exposure for subjects in the analysis was 8.4 ppm (standard deviation [SD] = 5.7). The mean Social Communication Questionnaire score was 8.0 (SD = 4.4). The mean prenatal methylmercury exposure for subjects with Social Responsiveness Scale scores was 6.7 ppm (SD = 4.4) and the mean Social Responsiveness Scale score was 57.6 (SD = 26.8). No consistent association between prenatal methylmercury exposure and ASD screening instrument was found, using linear and nonlinear regression analyses. CONCLUSIONS Prenatal exposure to methylmercury was not associated with ASD phenotypic behaviors in our cohort of high fish consumers. Our findings contribute to the growing literature suggesting that exposure to methylmercury does not play an important role in the development of ASD phenotypic behavior.
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Shaw C, Li Y, Tomljenovic L. Administration of aluminium to neonatal mice in vaccine-relevant amounts is associated with adverse long term neurological outcomes. J Inorg Biochem 2013; 128:237-44. [DOI: 10.1016/j.jinorgbio.2013.07.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/10/2013] [Accepted: 07/13/2013] [Indexed: 01/24/2023]
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30
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Cheng Y, Corbin JG, Levy RJ. Programmed cell death is impaired in the developing brain of FMR1 mutants. Dev Neurosci 2013; 35:347-58. [PMID: 23900139 DOI: 10.1159/000353248] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 05/21/2013] [Indexed: 11/19/2022] Open
Abstract
Fragile X syndrome (FXS), due to transcriptional silencing of fragile X mental retardation protein (FMRP), is characterized by excess synaptic connections and impaired dendrite maturation. Programmed cell death (PCD) is critical for synaptogenesis and elimination of aberrant neuronal connections in the developing brain; however, the role of FMRP in PCD is unknown. The aim of this work was to assess the intrinsic apoptosis pathway in the developing brain of Fmr1 mutants. To accomplish this, we evaluated two different Fmr1 mutant strains of 10-day-old male mice compared with appropriate controls. We performed immunohistochemistry for activated caspase-3 and TUNEL assays, quantified the number of neurons in neocortex and hippocampus, determined cytochrome c peroxidase activity, measured the amount of cytochrome c release from forebrain mitochondria, and assessed levels of key pro- and antiapoptotic mediators with immunoblot analysis. Both Fmr1 mutant strains demonstrated decreased apoptosis in neocortex, hippocampus, and basolateral amygdala, impaired cytochrome c and procaspase-9 release from mitochondria despite intact Bax translocation, increased expression of the antiapoptotic protein, BCL-xL, and increased number of neurons. Taken together, the data suggest that PCD is impaired due to increased BCL-xL expression and is associated with excess neurons in the developing brain of FMRP-deficient mice. It is possible that deficient PCD prevents neuron elimination and results in abnormal retention of developmentally transient neurons. Thus, defective PCD may contribute to the excess synaptic connections known to exist in Fmr1 mutants and could play a role in the behavioral phenotype of children with FXS.
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Affiliation(s)
- Ying Cheng
- Division of Anesthesiology and Pain Medicine, Children's National Medical Center, The George Washington University School of Medicine and Health Sciences, Washington, DC 20010, USA
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31
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Effect of thimerosal, methylmercury, and mercuric chloride in Jurkat T Cell Line. Interdiscip Toxicol 2013; 5:159-61. [PMID: 23554557 PMCID: PMC3600517 DOI: 10.2478/v10102-012-0026-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 06/20/2012] [Accepted: 06/30/2012] [Indexed: 11/27/2022] Open
Abstract
Mercury is a ubiquitous environmental toxicant that causes a wide range of adverse health effects in humans. Three forms of mercury exist: elemental, inorganic and organic. Each of them has its own profile of toxicity. The aim of the present study was to determine the effect of thimerosal, a topical antiseptic and preservative in vaccines routinely given to children, methyl mercury, and mercuric chloride on cellular viability measured by MTT in Jurkat T cells, a human T leukemia cell line. The treatment of Jurkat T cells with thimerosal caused a significant decrease in cellular viability at 1 μM (25%, p<0.05; IC50: 10 μM). Methyl mercury exhibited a significant decrease in cellular viability at 50 μM (33%, p<0.01; IC50: 65 μM). Mercuric chloride (HgCl2) did not show any significant change in cellular survival. Our findings showed that contrary to thimerosal and methyl mercury, mercuric chloride did not modify Jurkat T cell viability.
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Hunsaker MR. The importance of considering all attributes of memory in behavioral endophenotyping of mouse models of genetic disease. Behav Neurosci 2013; 126:371-80. [PMID: 22642882 DOI: 10.1037/a0028453] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In order to overcome difficulties in evaluating cognitive function in mouse models of genetic disorders, it is critical to take into account the background strain of the mouse and reported phenotypes in the clinical population being studied. Recent studies have evaluated cognitive function across a number of background strains and found that spatial memory assayed by the water maze and contextual fear conditioning often does not provide optimal results. The logical extension to these results is to emphasize not only spatial, but all attributes or domains of memory function in behavioral phenotyping experiments. A careful evaluation of spatial, temporal, sensory/perceptual, affective, response, executive, proto-linguistic, and social behaviors designed to specifically evaluate the cognitive function each mouse model can be performed in a rapid, relatively high throughput manner. Such results would not only provide a more comprehensive snapshot of brain function in mouse disease models than the more common approach that approaches nonspecific spatial memory tasks to evaluate cognition, but also would better model the disorders being studied.
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Affiliation(s)
- Michael R Hunsaker
- Department of Neurological Surgery, University of California, Davis, CA 95616, USA.
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33
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Genetic Basis and Neural Mechanism of Autism Spectrum Disorder*. PROG BIOCHEM BIOPHYS 2012. [DOI: 10.3724/sp.j.1206.2011.00519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Empirical Data Confirm Autism Symptoms Related to Aluminum and Acetaminophen Exposure. ENTROPY 2012. [DOI: 10.3390/e14112227] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Mrozek-Budzyn D, Majewska R, Kieltyka A, Augustyniak M. Neonatal exposure to Thimerosal from vaccines and child development in the first 3years of life. Neurotoxicol Teratol 2012; 34:592-7. [DOI: 10.1016/j.ntt.2012.10.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 10/03/2012] [Accepted: 10/05/2012] [Indexed: 11/27/2022]
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36
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Yeter D, Deth R. ITPKC susceptibility in Kawasaki syndrome as a sensitizing factor for autoimmunity and coronary arterial wall relaxation induced by thimerosal's effects on calcium signaling via IP3. Autoimmun Rev 2012; 11:903-8. [DOI: 10.1016/j.autrev.2012.03.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2012] [Accepted: 03/22/2012] [Indexed: 12/12/2022]
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MacFabe DF. Short-chain fatty acid fermentation products of the gut microbiome: implications in autism spectrum disorders. MICROBIAL ECOLOGY IN HEALTH AND DISEASE 2012; 23:19260. [PMID: 23990817 PMCID: PMC3747729 DOI: 10.3402/mehd.v23i0.19260] [Citation(s) in RCA: 193] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Recent evidence suggests potential, but unproven, links between dietary, metabolic, infective, and gastrointestinal factors and the behavioral exacerbations and remissions of autism spectrum disorders (ASDs). Propionic acid (PPA) and its related short-chain fatty acids (SCFAs) are fermentation products of ASD-associated bacteria (Clostridia, Bacteriodetes, Desulfovibrio). SCFAs represent a group of compounds derived from the host microbiome that are plausibly linked to ASDs and can induce widespread effects on gut, brain, and behavior. Intraventricular administration of PPA and SCFAs in rats induces abnormal motor movements, repetitive interests, electrographic changes, cognitive deficits, perseveration, and impaired social interactions. The brain tissue of PPA-treated rats shows a number of ASD-linked neurochemical changes, including innate neuroinflammation, increased oxidative stress, glutathione depletion, and altered phospholipid/acylcarnitine profiles. These directly or indirectly contribute to acquired mitochondrial dysfunction via impairment in carnitine-dependent pathways, consistent with findings in patients with ASDs. Of note, common antibiotics may impair carnitine-dependent processes by altering gut flora favoring PPA-producing bacteria and by directly inhibiting carnitine transport across the gut. Human populations that are partial metabolizers of PPA are more common than previously thought. PPA has further bioactive effects on neurotransmitter systems, intracellular acidification/calcium release, fatty acid metabolism, gap junction gating, immune function, and alteration of gene expression that warrant further exploration. These findings are consistent with the symptoms and proposed underlying mechanisms of ASDs and support the use of PPA infusions in rats as a valid animal model of the condition. Collectively, this offers further support that gut-derived factors, such as dietary or enteric bacterially produced SCFAs, may be plausible environmental agents that can trigger ASDs or ASD-related behaviors and deserve further exploration in basic science, agriculture, and clinical medicine.
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Affiliation(s)
- Derrick F. MacFabe
- Director: The Kilee Patchell-Evans Autism Research Group, Departments of Psychology (Neuroscience) and Psychiatry, Division of Developmental Disabilities, Lawson Research Institute, University of Western Ontario, London, ON, Canada, N6A 5C2
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Autism spectrum disorders. Transl Neurosci 2012. [DOI: 10.1017/cbo9780511980053.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Prenatal and Postnatal Epigenetic Programming: Implications for GI, Immune, and Neuronal Function in Autism. AUTISM RESEARCH AND TREATMENT 2012; 2012:190930. [PMID: 22934169 PMCID: PMC3420412 DOI: 10.1155/2012/190930] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 05/03/2012] [Indexed: 12/13/2022]
Abstract
Although autism is first and foremost a disorder of the central nervous system, comorbid dysfunction of the gastrointestinal (GI) and immune systems is common, suggesting that all three systems may be affected by common molecular mechanisms. Substantial systemic deficits in the antioxidant glutathione and its precursor, cysteine, have been documented in autism in association with oxidative stress and impaired methylation. DNA and histone methylation provide epigenetic regulation of gene expression during prenatal and postnatal development. Prenatal epigenetic programming (PrEP) can be affected by the maternal metabolic and nutritional environment, whereas postnatal epigenetic programming (PEP) importantly depends upon nutritional support provided through the GI tract. Cysteine absorption from the GI tract is a crucial determinant of antioxidant capacity, and systemic deficits of glutathione and cysteine in autism are likely to reflect impaired cysteine absorption. Excitatory amino acid transporter 3 (EAAT3) provides cysteine uptake for GI epithelial, neuronal, and immune cells, and its activity is decreased during oxidative stress. Based upon these observations, we propose that neurodevelopmental, GI, and immune aspects of autism each reflect manifestations of inadequate antioxidant capacity, secondary to impaired cysteine uptake by the GI tract. Genetic and environmental factors that adversely affect antioxidant capacity can disrupt PrEP and/or PEP, increasing vulnerability to autism.
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Abstract
That vaccines do not cause autism is now a widely accepted proposition, though a few dissenters remain. An 8-year court process in the US federal vaccine injury compensation court ended in 2010 with rulings that autism was not an adverse reaction to vaccination. There were two sets of trials: one against the measles-mumps-rubella (MMR) vaccine and one against the mercury-based preservative thimerosal. The MMR story is more widely known because of publicity surrounding the main proponent of an MMR-autism link, British doctor Andrew Wakefield, but the story of thimerosal in court is largely untold. This study examines the credibility battles and boundary work in the two cases, illuminating the sustaining world of alternative science that supported the parents, lawyers, researchers, and expert witnesses against vaccines. After the loss in court, the families and their advocates transformed their scientific arguments into an indictment of procedural injustice in the vaccine court. I argue that the very efforts designed to produce legitimacy in this type of lopsided dispute will be counter-mobilized as evidence of injustice, helping us understand why settling a scientific controversy in court does not necessarily mean changing anyone's mind.
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Affiliation(s)
- Anna Kirkland
- Women's Studies and Political Science, University of Michigan, Ann Arbor, MI 48104-1290, USA.
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41
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Cheng Y, Thomas A, Mardini F, Bianchi SL, Tang JX, Peng J, Wei H, Eckenhoff MF, Eckenhoff RG, Levy RJ. Neurodevelopmental consequences of sub-clinical carbon monoxide exposure in newborn mice. PLoS One 2012; 7:e32029. [PMID: 22348142 PMCID: PMC3277503 DOI: 10.1371/journal.pone.0032029] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Accepted: 01/18/2012] [Indexed: 12/13/2022] Open
Abstract
Carbon monoxide (CO) exposure at high concentrations results in overt neurotoxicity. Exposure to low CO concentrations occurs commonly yet is usually sub-clinical. Infants are uniquely vulnerable to a variety of toxins, however, the effects of postnatal sub-clinical CO exposure on the developing brain are unknown. Apoptosis occurs normally within the brain during development and is critical for synaptogenesis. Here we demonstrate that brief, postnatal sub-clinical CO exposure inhibits developmental neuroapoptosis resulting in impaired learning, memory, and social behavior. Three hour exposure to 5 ppm or 100 ppm CO impaired cytochrome c release, caspase-3 activation, and apoptosis in neocortex and hippocampus of 10 day old CD-1 mice. CO increased NeuN protein, neuronal numbers, and resulted in megalencephaly. CO-exposed mice demonstrated impaired memory and learning and reduced socialization following exposure. Thus, CO-mediated inhibition of neuroapoptosis might represent an important etiology of acquired neurocognitive impairment and behavioral disorders in children.
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Affiliation(s)
- Ying Cheng
- Division of Anesthesiology and Pain Medicine, Children's National Medical Center, The George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
| | - Adia Thomas
- Division of Anesthesiology and Pain Medicine, Children's National Medical Center, The George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
| | - Feras Mardini
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Shannon L. Bianchi
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Junxia X. Tang
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Jun Peng
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Huafeng Wei
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Maryellen F. Eckenhoff
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Roderic G. Eckenhoff
- Department of Anesthesiology and Critical Care, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Richard J. Levy
- Division of Anesthesiology and Pain Medicine, Children's National Medical Center, The George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
- * E-mail:
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Duszczyk-Budhathoki M, Olczak M, Lehner M, Majewska MD. Administration of thimerosal to infant rats increases overflow of glutamate and aspartate in the prefrontal cortex: protective role of dehydroepiandrosterone sulfate. Neurochem Res 2012; 37:436-47. [PMID: 22015977 PMCID: PMC3264864 DOI: 10.1007/s11064-011-0630-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 09/27/2011] [Accepted: 10/04/2011] [Indexed: 12/21/2022]
Abstract
Thimerosal, a mercury-containing vaccine preservative, is a suspected factor in the etiology of neurodevelopmental disorders. We previously showed that its administration to infant rats causes behavioral, neurochemical and neuropathological abnormalities similar to those present in autism. Here we examined, using microdialysis, the effect of thimerosal on extracellular levels of neuroactive amino acids in the rat prefrontal cortex (PFC). Thimerosal administration (4 injections, i.m., 240 μg Hg/kg on postnatal days 7, 9, 11, 15) induced lasting changes in amino acid overflow: an increase of glutamate and aspartate accompanied by a decrease of glycine and alanine; measured 10-14 weeks after the injections. Four injections of thimerosal at a dose of 12.5 μg Hg/kg did not alter glutamate and aspartate concentrations at microdialysis time (but based on thimerosal pharmacokinetics, could have been effective soon after its injection). Application of thimerosal to the PFC in perfusion fluid evoked a rapid increase of glutamate overflow. Coadministration of the neurosteroid, dehydroepiandrosterone sulfate (DHEAS; 80 mg/kg; i.p.) prevented the thimerosal effect on glutamate and aspartate; the steroid alone had no influence on these amino acids. Coapplication of DHEAS with thimerosal in perfusion fluid also blocked the acute action of thimerosal on glutamate. In contrast, DHEAS alone reduced overflow of glycine and alanine, somewhat potentiating the thimerosal effect on these amino acids. Since excessive accumulation of extracellular glutamate is linked with excitotoxicity, our data imply that neonatal exposure to thimerosal-containing vaccines might induce excitotoxic brain injuries, leading to neurodevelopmental disorders. DHEAS may partially protect against mercurials-induced neurotoxicity.
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Affiliation(s)
- Michalina Duszczyk-Budhathoki
- Marie Curie Chairs Program at the Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, 02-957 Warsaw, Poland
| | - Mieszko Olczak
- Marie Curie Chairs Program at the Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, 02-957 Warsaw, Poland
- Department of Forensic Medicine, Medical University of Warsaw, Oczki 1 str., 02-007 Warsaw, Poland
| | - Malgorzata Lehner
- Department of Neurochemistry, Institute of Psychiatry and Neurology, 02-957 Warsaw, Poland
| | - Maria Dorota Majewska
- Marie Curie Chairs Program at the Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, 02-957 Warsaw, Poland
- Department of Biology and Environmental Science, University of Cardinal Stefan Wyszynski, Wóycickiego Str. 1/3, 01-815 Warsaw, Poland
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Kirkland A. The legitimacy of vaccine critics: what is left after the autism hypothesis? JOURNAL OF HEALTH POLITICS, POLICY AND LAW 2012; 37:69-97. [PMID: 22003097 DOI: 10.1215/03616878-1496020] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The last dozen years have seen a massive transnational mobilization of the legal, political, and research communities in response to the worrisome hypothesis that vaccines could have a link to childhood autism and other developmental conditions. Vaccine critics, some already organized and some composed of newly galvanized parents, developed an alternate world of internally legitimating studies, blogs, conferences, publications, and spokespeople to affirm a connection. When the consensus turned against the autism hypothesis, these structures and a committed membership base unified all the organizations in resistance. This article examines the relationship between mobilization based on science and the trajectory of legitimacy vaccine criticism has taken. I argue that vaccine critics have run up against the limits of legitimate scientific argument and are now in the curious position of both doubling down on credibility-depleting stances and innovating new and possibly resonant formulations.
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OWHADI HOUMAN, BOULOS AREEN. BISTABLE EQUILIBRIUM POINTS OF MERCURY BODY BURDEN. J BIOL SYST 2011. [DOI: 10.1142/s0218339008002459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In the last century, mercury levels in the global environment have tripled as a result of increased pollution from industrial, occupational, medicinal and domestic uses.1 Glutathione is known to be the main agent responsible for the excretion of mercury (Refs. 2 to 4). It has also been shown that mercury inhibits glutathione synthetase (an enzyme acting in the synthesization of glutathione), therefore leading to decreased glutathione levels (Refs. 5 to 7). Mercury also interferes with the production of heme in the porphyrin pathway.8 Heme is needed for biological energy production and ability to detox organic toxins via the P450 enzymes.9 The purpose of this paper is to show that the body's response to mercury exposure is hysteretic, i.e. when this feedback of mercury on its main detoxifying agents is strong enough, then mercury body burden has two points of equilibrium: one with normal abilities to detoxify and low levels of mercury and one with inhibited abilities to detoxify and high levels of mercury. Furthermore, a small increase of the body's mercury burden may not be sufficient to trigger observable neurotoxic effects but it may be sufficient to act as a switch leading to an accumulation of mercury in the body through environmental exposure until its toxicity is manifested.
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Affiliation(s)
- HOUMAN OWHADI
- Applied and Computational Mathematics, and Control and Dynamical Systems, California Institute of Technology, MC 217-50, Pasadena, CA 91125, USA
| | - AREEN BOULOS
- Applied and Computational Mathematics, and Control and Dynamical Systems, California Institute of Technology, MC 217-50, Pasadena, CA 91125, USA
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Olczak M, Duszczyk M, Mierzejewski P, Meyza K, Majewska MD. Persistent behavioral impairments and alterations of brain dopamine system after early postnatal administration of thimerosal in rats. Behav Brain Res 2011; 223:107-18. [DOI: 10.1016/j.bbr.2011.04.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 04/14/2011] [Accepted: 04/20/2011] [Indexed: 11/15/2022]
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Thomas Curtis J, Chen Y, Buck DJ, Davis RL. Chronic inorganic mercury exposure induces sex-specific changes in central TNFα expression: importance in autism? Neurosci Lett 2011; 504:40-4. [PMID: 21906657 DOI: 10.1016/j.neulet.2011.08.053] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 08/22/2011] [Accepted: 08/24/2011] [Indexed: 11/19/2022]
Abstract
Mercury is neurotoxic and increasing evidence suggests that environmental exposure to mercury may contribute to neuropathologies including Alzheimer's disease and autism spectrum disorders. Mercury is known to disrupt immunocompetence in the periphery, however, little is known about the effects of mercury on neuroimmune signaling. Mercury-induced effects on central immune function are potentially very important given that mercury exposure and neuroinflammation both are implicated in certain neuropathologies (i.e., autism). Furthermore, mounting evidence points to the involvement of glial activation in autism. Therefore, we utilized an in vivo model to assess the effects of mercury exposure on neuroimmune signaling. In prairie voles, 10 week mercury exposure (60ppm HgCl(2) in drinking water) resulted in a male-specific increase in TNFα protein expression in the cerebellum and hippocampus. These findings are consistent with our previously reported male-specific mercury-induced deficits in social behavior and further support a role for heavy metals exposure in neuropathologies such as autism. Subsequent studies should further evaluate the mechanism of action and biological consequences of heavy metals exposure. Additionally, these observations highlight the potential of neuroimmune markers in male voles as biomarkers of environmental mercury toxicity.
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Affiliation(s)
- J Thomas Curtis
- Department of Pharmacology/Physiology, Oklahoma State University Center for Health Sciences, 1111 West 17th Street, Tulsa, OK 74107, United States
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Kennedy JS, Lawrence DA. Coincidental associations do not provide proof for the etiology of autism. J Immunotoxicol 2011; 8:198-203. [PMID: 21675928 DOI: 10.3109/1547691x.2011.584920] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Dórea JG. Integrating Experimental (In Vitro and In Vivo) Neurotoxicity Studies of Low-dose Thimerosal Relevant to Vaccines. Neurochem Res 2011; 36:927-38. [DOI: 10.1007/s11064-011-0427-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2011] [Indexed: 12/01/2022]
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Mutter J. Is dental amalgam safe for humans? The opinion of the scientific committee of the European Commission. J Occup Med Toxicol 2011; 6:2. [PMID: 21232090 PMCID: PMC3025977 DOI: 10.1186/1745-6673-6-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Accepted: 01/13/2011] [Indexed: 01/06/2023] Open
Abstract
It was claimed by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)) in a report to the EU-Commission that "....no risks of adverse systemic effects exist and the current use of dental amalgam does not pose a risk of systemic disease..." [1, available from: http://ec.europa.eu/health/ph_risk/committees/04_scenihr/docs/scenihr_o_016.pdf].SCENIHR disregarded the toxicology of mercury and did not include most important scientific studies in their review. But the real scientific data show that:(a) Dental amalgam is by far the main source of human total mercury body burden. This is proven by autopsy studies which found 2-12 times more mercury in body tissues of individuals with dental amalgam. Autopsy studies are the most valuable and most important studies for examining the amalgam-caused mercury body burden.(b) These autopsy studies have shown consistently that many individuals with amalgam have toxic levels of mercury in their brains or kidneys.(c) There is no correlation between mercury levels in blood or urine, and the levels in body tissues or the severity of clinical symptoms. SCENIHR only relied on levels in urine or blood.(d) The half-life of mercury in the brain can last from several years to decades, thus mercury accumulates over time of amalgam exposure in body tissues to toxic levels. However, SCENIHR state that the half-life of mercury in the body is only "20-90 days".(e) Mercury vapor is about ten times more toxic than lead on human neurons and with synergistic toxicity to other metals.(f) Most studies cited by SCENIHR which conclude that amalgam fillings are safe have severe methodical flaws.
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Affiliation(s)
- Joachim Mutter
- Department of Environmental and integrative medicine Lohnerhofstraße 2, 78467 Constance/Germany.
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Olczak M, Duszczyk M, Mierzejewski P, Bobrowicz T, Majewska MD. Neonatal administration of thimerosal causes persistent changes in mu opioid receptors in the rat brain. Neurochem Res 2010; 35:1840-7. [PMID: 20803069 PMCID: PMC2957583 DOI: 10.1007/s11064-010-0250-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2010] [Indexed: 10/26/2022]
Abstract
Thimerosal added to some pediatric vaccines is suspected in pathogenesis of several neurodevelopmental disorders. Our previous study showed that thimerosal administered to suckling rats causes persistent, endogenous opioid-mediated hypoalgesia. Here we examined, using immunohistochemical staining technique, the density of μ-opioid receptors (MORs) in the brains of rats, which in the second postnatal week received four i.m. injections of thimerosal at doses 12, 240, 1,440 or 3,000 μg Hg/kg. The periaqueductal gray, caudate putamen and hippocampus were examined. Thimerosal administration caused dose-dependent statistically significant increase in MOR densities in the periaqueductal gray and caudate putamen, but decrease in the dentate gyrus, where it was accompanied by the presence of degenerating neurons and loss of synaptic vesicle marker (synaptophysin). These data document that exposure to thimerosal during early postnatal life produces lasting alterations in the densities of brain opioid receptors along with other neuropathological changes, which may disturb brain development.
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Affiliation(s)
- Mieszko Olczak
- Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, Sobieskiego 9 str., 02-957 Warsaw, Poland
- Department of Forensic Medicine, Medical University of Warsaw, Oczki 1 str., 02-007 Warsaw, Poland
| | - Michalina Duszczyk
- Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, Sobieskiego 9 str., 02-957 Warsaw, Poland
| | - Pawel Mierzejewski
- Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, Sobieskiego 9 str., 02-957 Warsaw, Poland
| | - Teresa Bobrowicz
- Department of Neuropathology, Institute of Psychiatry and Neurology, 02-957 Warsaw, Poland
| | - Maria Dorota Majewska
- Department of Pharmacology and Physiology of the Nervous System, Institute of Psychiatry and Neurology, Sobieskiego 9 str., 02-957 Warsaw, Poland
- Department of Biology and Environmental Science, University of Cardinal Stefan Wyszynski, Wóycickiego Str. 1/3, 01-815 Warsaw, Poland
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