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Shiani A, Sharafi K, Omer AK, Kiani A, Karamimatin B, Massahi T, Ebrahimzadeh G. A systematic literature review on the association between exposures to toxic elements and an autism spectrum disorder. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159246. [PMID: 36220469 DOI: 10.1016/j.scitotenv.2022.159246] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/30/2022] [Accepted: 10/01/2022] [Indexed: 05/16/2023]
Abstract
BACKGROUND AND AIM Autism spectrum disorder (ASD) is a neurodevelopmental illness characterized by difficulties in social communication and repetitive behaviors. There have been many previous studies of toxic metals in ASD. Therefore, the priority of this study is to review the relationships between exposure to toxic metals and ASD. MATERIALS & METHODS This study was based on a comprehensive search of international databases, such as Web of Science, Science Direct, Scopus, PubMed, and Google Scholar, for all works related to the subject under discussion from 1982 to 2022. We further summarize published data linked to this topic and discuss with clarifying evidence that agrees and conflicts with the association between exposure to toxic metals, including mercury (Hg), lead (Pb), cadmium (Cd), arsenic (As), and aluminum (Al) and ASD. RESULTS 40 out of 63 papers met the requirements for meta-analysis. Blood Pb levels (standardized mean difference (SMD) = 0.81; 95 % confidence interval (CI): 0.36-1.25), blood Hg (SMD = 0.90; CI: 0.30-1.49), hair Pb (SMD = 1.47; CI: 0.03-2.92), urine As (SMD = 0.65; CI: 0.22-1.09), and urine Al levels (SMD = 0.85; CI: 0.40-1.29) in autistic individuals were significantly higher than those of healthy control (HC). Whereas, blood As levels (SMD = 1.33; CI: -1.32-3.97), hair As (SMD = 0.55; CI: -0.14-1.24), hair Cd (SMD = 0.60; CI: -0.31-1.51), hair Hg (SMD = 0.41; CI: -0.30-1.12), hair Al (SMD = 0.87; CI: -0.02-1.77), urine Pb (SMD = -0.68; CI: -2.55-1.20), urine Cd (SMD = -0.26; CI: -0.94-0.41), and urine Hg levels (SMD = 0.47; CI: -0.09-1.04) in autistic individuals were significantly lower than those of HC. CONCLUSION Toxic metal content significantly differed between individuals with ASD and HC in the current meta-analysis. The results assist in clarifying the significance of toxic metals as environmental factors in the development of ASD.
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Affiliation(s)
- Amir Shiani
- Department of Speech Therapy, School of Rehabilitation Sciences, Kermanshah University of Medical Sciences, Kermanshah, Iran; Clinical Research Development Center, Taleghani and Imam Ali Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Kiomars Sharafi
- Research Center for Environmental Determinants of Health (RCEDH), Research Institute for Health, Kermanshah University of Medical Sciences, Kermanshah, Iran; Department of Environmental Health Engineering, School of Public Health, Kermanshah University of Medical Sciences, Kermanshah, Iran.
| | - Abdullah Khalid Omer
- Department of Food Hygiene and Quality Control, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran; Razga Company, Kurdistan Region, Iraq.
| | - Amir Kiani
- Regenerative Medicine Research Center (RMRC), Kermanshah University of Medical Sciences, Kermanshah, Iran; Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Behzad Karamimatin
- Research Center for Environmental Determinants of Health (RCEDH), Research Institute for Health, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Tooraj Massahi
- Students Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Gholamreza Ebrahimzadeh
- Department of Environmental Health Engineering, School of Public Health, Zabol University of Medical Sciences, Zabol, Iran
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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: 0] [Impact Index Per Article: 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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Dougnon G, Matsui H. Modelling Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) Using Mice and Zebrafish. Int J Mol Sci 2022; 23:ijms23147550. [PMID: 35886894 PMCID: PMC9319972 DOI: 10.3390/ijms23147550] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/01/2022] [Accepted: 07/04/2022] [Indexed: 02/06/2023] Open
Abstract
Autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD) are two debilitating neurodevelopmental disorders. The former is associated with social impairments whereas the latter is associated with inattentiveness, hyperactivity, and impulsivity. There is recent evidence that both disorders are somehow related and that genes may play a large role in these disorders. Despite mounting human and animal research, the neurological pathways underlying ASD and ADHD are still not well understood. Scientists investigate neurodevelopmental disorders by using animal models that have high similarities in genetics and behaviours with humans. Mice have been utilized in neuroscience research as an excellent animal model for a long time; however, the zebrafish has attracted much attention recently, with an increasingly large number of studies using this model. In this review, we first discuss ASD and ADHD aetiology from a general point of view to their characteristics and treatments. We also compare mice and zebrafish for their similarities and discuss their advantages and limitations in neuroscience. Finally, we summarize the most recent and existing research on zebrafish and mouse models of ASD and ADHD. We believe that this review will serve as a unique document providing interesting information to date about these models, thus facilitating research on ASD and ADHD.
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Shamsutdinova OA, Bulgin DV, Karal-Ogly DD, Lavrentieva IN, Klots IN. [Comparative analysis of residual neurovirulence of vaccine and low attenuated rubella virus (Matonaviridae: Rubivirus: Rubella virus) strains in the experiments on the macaque rhesus (Macaca mulatta) monkeys]. Vopr Virusol 2022; 67:133-141. [PMID: 35521986 DOI: 10.36233/0507-4088-97] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Rubella is currently an infection controlled by specific prophylaxis. Not only the right vaccine prophylaxis strategy and tactics, but also the use of effective and safe vaccine preparations is crucial for the elimination of this disease.The aim of the investigation was to study the morphological and pathogenetic patterns of changes developing in the central nervous system (CNS) and internal organs of monkeys (Haplorhini) during intracerebral inoculation with 2 strains of rubella virus (Matonaviridae: Rubivirus: Rubella virus) (RV): highly attenuated Orlov-B, and low attenuated Orlov-14. MATERIAL AND METHODS In the experiments, seronegative rhesus macaque monkeys (Macaca mulatta) weighing 3.3-5.1 kg (n = 7) were used. Neurovirulence of the strains was determined by a complex of clinical, pathomorphological, and virological methods. RESULTS AND DISCUSSION It was found that during attenuation, the Orlov-B strain lost the ability to replicate in CNS cells and induce moderate/expressed specific changes in them, as well as to overcome the blood-brain barrier and cause the damage of sensitive organs and tissues. This fact indicates a low level of residual neurovirulence of the vaccine strain. CONCLUSION The results obtained in this study regarding the clinical symptoms of CNS lesions and the nature of the pathological process in its tissues in experimental animals can be significant for the improvement of safety control of live rubella vaccines. These data indicate that the Orlov-B strain can be considered as a candidate strain for further study on the development of a rubella vaccine based on the domestic vaccine strain.
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Affiliation(s)
- O A Shamsutdinova
- FSBRI «Research Institute of Medical Primatology» of the Ministry of Education and Science of Russia
| | - D V Bulgin
- FSBRI «Research Institute of Medical Primatology» of the Ministry of Education and Science of Russia
| | - D D Karal-Ogly
- FSBRI «Research Institute of Medical Primatology» of the Ministry of Education and Science of Russia
| | - I N Lavrentieva
- FSBI «Saint Petersburg Pasteur Research Institute of Epidemiology and Microbiology» of the Federal Service for Surveillance on Consumer Rights Protection and Human Welfare (Rospotrebnadzor)
| | - I N Klots
- FSBRI «Research Institute of Medical Primatology» of the Ministry of Education and Science of Russia
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Kaur I, Behl T, Aleya L, Rahman MH, Kumar A, Arora S, Akter R. Role of metallic pollutants in neurodegeneration: effects of aluminum, lead, mercury, and arsenic in mediating brain impairment events and autism spectrum disorder. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:8989-9001. [PMID: 33447979 DOI: 10.1007/s11356-020-12255-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 12/27/2020] [Indexed: 04/16/2023]
Abstract
Autism spectrum disorder (ASD) is a developmental disorder of the brain characterized by shortfall in the social portfolio of an individual and abbreviated interactive and communication aspects rendering stereotypical behavior and pitfalls in a child's memory, thinking, and learning capabilities. The incidence of ASD has accelerated since the past decade, portraying environment as one of the primary assets, comprising of metallic components aiming to curb the neurodevelopmental pathways in an individual. Many regulations like Clean Air Act and critical steps taken by countries all over the globe, like Sweden and the USA, have rendered the necessity to study the effects of environmental metallic components on ASD progression. The review focuses on the primary metallic components present in the environment (aluminum, lead, mercury, and arsenic), responsible for accelerating ASD symptoms by a set of general mechanisms like oxidative stress reduction, glycolysis suppression, microglial activation, and metalloprotein disruption, resulting in apoptotic signaling, neurotoxic effects, and neuroinflammatory responses. The effect of these metals can be retarded by certain protective strategies like chelation, dietary correction, certain agents (curcumin, mangiferin, selenium), and detoxification enhancement, which can necessarily halt the neurodegenerative effects.
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Affiliation(s)
- Ishnoor Kaur
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Tapan Behl
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India.
| | - Lotfi Aleya
- Chrono-Environnement Laboratory, UMR CNRS 6249, Bourgogne Franche-Comté University, Paris, France
| | - Md Habibur Rahman
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Seoul, South Korea
- Department of Pharmacy, Southeast University, Banani, Dhaka, Bangladesh
| | - Arun Kumar
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Sandeep Arora
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Rokeya Akter
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Seoul, South Korea
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Pottel J, Armstrong D, Zou L, Fekete A, Huang XP, Torosyan H, Bednarczyk D, Whitebread S, Bhhatarai B, Liang G, Jin H, Ghaemi SN, Slocum S, Lukacs KV, Irwin JJ, Berg EL, Giacomini KM, Roth BL, Shoichet BK, Urban L. The activities of drug inactive ingredients on biological targets. Science 2020; 369:403-413. [PMID: 32703874 DOI: 10.1126/science.aaz9906] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 05/18/2020] [Indexed: 12/22/2022]
Abstract
Excipients, considered "inactive ingredients," are a major component of formulated drugs and play key roles in their pharmacokinetics. Despite their pervasiveness, whether they are active on any targets has not been systematically explored. We computed the likelihood that approved excipients would bind to molecular targets. Testing in vitro revealed 25 excipient activities, ranging from low-nanomolar to high-micromolar concentration. Another 109 activities were identified by testing against clinical safety targets. In cellular models, five excipients had fingerprints predictive of system-level toxicity. Exposures of seven excipients were investigated, and in certain populations, two of these may reach levels of in vitro target potency, including brain and gut exposure of thimerosal and its major metabolite, which had dopamine D3 receptor dissociation constant K d values of 320 and 210 nM, respectively. Although most excipients deserve their status as inert, many approved excipients may directly modulate physiologically relevant targets.
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Affiliation(s)
- Joshua Pottel
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Duncan Armstrong
- Preclinical Safety, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - Ling Zou
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, USA
| | - Alexander Fekete
- Preclinical Safety, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - Xi-Ping Huang
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27759, USA
| | - Hayarpi Torosyan
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Dallas Bednarczyk
- PK Sciences, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - Steven Whitebread
- Preclinical Safety, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - Barun Bhhatarai
- PK Sciences, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - Guiqing Liang
- PK Sciences, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - Hong Jin
- Preclinical Safety, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA
| | - S Nassir Ghaemi
- Translational Medicine, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA.,Tufts University School of Medicine, Boston, MA 02111, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Samuel Slocum
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27759, USA
| | - Katalin V Lukacs
- National Heart and Lung Institute, Imperial College, London SW7 2AZ, UK
| | - John J Irwin
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA
| | - Ellen L Berg
- Eurofins, DiscoverX, South San Francisco, CA 94080, USA
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94158, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina, Chapel Hill, NC 27759, USA
| | - Brian K Shoichet
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94158, USA.
| | - Laszlo Urban
- Preclinical Safety, Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA.
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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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Ryan AM, Berman RF, Bauman MD. Bridging the species gap in translational research for neurodevelopmental disorders. Neurobiol Learn Mem 2019; 165:106950. [PMID: 30347236 PMCID: PMC6474835 DOI: 10.1016/j.nlm.2018.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/19/2018] [Accepted: 10/17/2018] [Indexed: 02/07/2023]
Abstract
The prevalence and societal impact of neurodevelopmental disorders (NDDs) continue to increase despite years of research in both patient populations and animal models. There remains an urgent need for translational efforts between clinical and preclinical research to (i) identify and evaluate putative causes of NDD, (ii) determine their underlying neurobiological mechanisms, (iii) develop and test novel therapeutic approaches, and (iv) translate basic research into safe and effective clinical practices. Given the complexity behind potential causes and behaviors affected by NDDs, modeling these uniquely human brain disorders in animals will require that we capitalize on unique advantages of a diverse array of species. While much NDD research has been conducted in more traditional animal models such as the mouse, ultimately, we may benefit from creating animal models with species that have a more sophisticated social behavior repertoire such as the rat (Rattus norvegicus) or species that more closely related to humans, such as the rhesus macaque (Macaca mulatta). Here, we highlight the rat and rhesus macaque models for their role in previous psychological research discoveries, current efforts to understand the neurobiology of NDDs, and focus on the convergence of behavior outcome measures that parallel features of human NDDs.
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Affiliation(s)
- A M Ryan
- The UC Davis MIND Institute, University of California, Davis, United States; Department of Psychiatry and Behavioral Sciences, University of California, Davis, United States; California National Primate Research Center, University of California, Davis, United States
| | - R F Berman
- The UC Davis MIND Institute, University of California, Davis, United States; Department of Neurological Surgery, University of California, Davis, United States
| | - M D Bauman
- The UC Davis MIND Institute, University of California, Davis, United States; Department of Psychiatry and Behavioral Sciences, University of California, Davis, United States; California National Primate Research Center, University of California, Davis, United States.
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Murphy AM, Dettmer AM. Impacts of early social experience on cognitive development in infant rhesus macaques. Dev Psychobiol 2019; 62:895-908. [PMID: 31531855 DOI: 10.1002/dev.21916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/15/2019] [Accepted: 07/27/2019] [Indexed: 11/11/2022]
Abstract
Although much is known about the influences of early life experiences on the neurobiology and behavior of macaque models of child development, there is scant literature on cognitive development with respect to early rearing. Here, we examined the effects of rearing condition on affective reactivity and cognitive development in infant rhesus macaques. Infants were pseudo-randomly assigned to one of the two rearing conditions: nursery reared (NR, N = 32; 16 peer-reared, 16 surrogate-peer-reared) or mother-peer-reared (MPR, N = 7). During the first month of life, infants were administered the Primate Neonatal Neurobehavioral Assessment (PNNA). Beginning at 4 months old, infants were tested on cognitive tasks that assessed reward association, cognitive flexibility, and impulsivity. We found no gross cognitive differences between MPR and NR infants. However, MPR infants were more reactive than NR infants on the PNNA. Additionally, reactivity on the PNNA correlated with impulsivity, such that infants who were more reactive at 1 month of age completed fewer trials correctly on this task at 8-10 months. These findings are the first to directly compare cognitive development in MPR and NR infants, and add to the existing literature elucidating the influences of early social experience on temperament and development.
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Affiliation(s)
- Ashley M Murphy
- Neuroscience and Behavior, California National Primate Research Center, Davis, CA, USA.,Department of Psychology, University of California, Davis, CA, USA.,Eunice Kennedy Shriver National Institute of Child Health & Human Development, National Institutes of Health, Poolesville, MD, USA
| | - Amanda M Dettmer
- Eunice Kennedy Shriver National Institute of Child Health & Human Development, National Institutes of Health, Poolesville, MD, USA.,Yale Child Study Center, Yale School of Medicine, New Haven, CT, USA
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10
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Qin D, Wu S, Chen Y, Hu X. Behavioral screening tools for identifying autism in macaques: existing and promising tests. Brain Res Bull 2019; 146:87-93. [PMID: 30605712 DOI: 10.1016/j.brainresbull.2018.12.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/11/2018] [Accepted: 12/28/2018] [Indexed: 02/05/2023]
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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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Bjørklund G, Skalny AV, Rahman MM, Dadar M, Yassa HA, Aaseth J, Chirumbolo S, Skalnaya MG, Tinkov AA. Toxic metal(loid)-based pollutants and their possible role in autism spectrum disorder. ENVIRONMENTAL RESEARCH 2018; 166:234-250. [PMID: 29902778 DOI: 10.1016/j.envres.2018.05.020] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/18/2018] [Accepted: 05/18/2018] [Indexed: 06/08/2023]
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social interaction, verbal and non-verbal communication, and stereotypic behaviors. Many studies support a significant relationship between many different environmental factors in ASD etiology. These factors include increased daily exposure to various toxic metal-based environmental pollutants, which represent a cause for concern in public health. This article reviews the most relevant toxic metals, commonly found, environmental pollutants, i.e., lead (Pb), mercury (Hg), aluminum (Al), and the metalloid arsenic (As). Additionally, it discusses how pollutants can be a possible pathogenetic cause of ASD through various mechanisms including neuroinflammation in different regions of the brain, fundamentally occurring through elevation of the proinflammatory profile of cytokines and aberrant expression of nuclear factor kappa B (NF-κB). Due to the worldwide increase in toxic environmental pollution, studies on the role of pollutants in neurodevelopmental disorders, including direct effects on the developing brain and the subjects' genetic susceptibility and polymorphism, are of utmost importance to achieve the best therapeutic approach and preventive strategies.
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Affiliation(s)
- Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Mo i Rana, Norway.
| | - Anatoly V Skalny
- Peoples' Friendship University of Russia (RUDN University), Moscow, Russia; Yaroslavl State University, Yaroslavl, Russia; All-Russian Research Institute of Medicinal and Aromatic Plants, Moscow, Russia
| | - Md Mostafizur Rahman
- Department of Environmental Sciences, Jahangirnagar University, Dhaka, Bangladesh; Graduate School of Environmental Science, Hokkaido University, Japan
| | - Maryam Dadar
- Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran
| | - Heba A Yassa
- Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Jan Aaseth
- Faculty of Health and Social Sciences, Inland Norway University of Applied Sciences, Elverum, Norway; Department of Research, Innlandet Hospital Trust, Brumunddal, Norway
| | - Salvatore Chirumbolo
- Department of Neurological and Movement Sciences, University of Verona, Verona, Italy
| | | | - Alexey A Tinkov
- Peoples' Friendship University of Russia (RUDN University), Moscow, Russia; Yaroslavl State University, Yaroslavl, Russia
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Dórea JG. Low-dose Thimerosal (ethyl-mercury) is still used in infants` vaccines: Should we be concerned with this form of exposure? J Trace Elem Med Biol 2018; 49:134-139. [PMID: 29895363 DOI: 10.1016/j.jtemb.2018.05.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 05/16/2018] [Indexed: 12/25/2022]
Abstract
In developing countries, Thimerosal-containing vaccines (TCV) are the main causes of organic Hg exposure for newborns, neonates, and infants immunized with TCV. This article addresses early-life exposure to this unique organic mercury compound (ethylmercury-EtHg) and the risks of its exposure. English language studies pertaining to Thimerosal/EtHg toxicity and exposure during early life were searched in PubMed; and, those publications judged to be relevant to the topic of this review were selected. The risk from the neurotoxic effects of pre- and post-natal Hg exposures depend, in part, on aggravating or attenuating environmental and/or genetic-associated factors. Health authorities in charge of controlling infectious disease dismiss the toxicology of mercury (immunological and subtle neurological effects as insignificant) related to low-dose Thimerosal. The review addresses the evidence that brings into question the safety of Thimerosal that is still present in vaccines given to pregnant women, infants, and children in developing countries, and recognizes the ethical imperative to extend the use of Thimerosal-free vaccines to developing countries, not just developed countries.
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Affiliation(s)
- José G Dórea
- Health Sciences, Universidade de Brasília, Brasília, 70919-970, DF, Brazil.
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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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Jia F, Shan L, Wang B, Li H, Miao C, Xu Z, Lin CP, Saad K. Bench to bedside review: Possible role of vitamin D in autism spectrum disorder. Psychiatry Res 2018; 260:360-365. [PMID: 29241119 DOI: 10.1016/j.psychres.2017.12.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/22/2017] [Accepted: 12/03/2017] [Indexed: 02/08/2023]
Abstract
Autism spectrum disorder (ASD) is a group of dysfunctions in social interaction, communication, and behaviors. Studies have demonstrated that vitamin D deficiency during pregnancy and in individuals increased the risk of ASD. A genetic polymorphism study has pinpointed that genotype AA/A-allele of GC rs4588 in children is associated with ASD, which encodes the vitamin D binding protein. Translating the mentioned points into clinical practice, several clinical trials have demonstrated that vitamin D supplementation can improve the core symptoms in children with ASD. One paper also showed that possible prophylactic effect for the reoccurrence of ASD by vitamin D supplement during pregnancy and early childhood. Herein, this review aims to address the recent advances in this field and to clarify the possible role of vitamin D in ASD.
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Affiliation(s)
- Feiyong Jia
- Department of Developmental and Behavioral Pediatrics, the First Hospital of Jilin University, Changchun, China
| | - Ling Shan
- Department of Developmental and Behavioral Pediatrics, the First Hospital of Jilin University, Changchun, China
| | - Bing Wang
- Department of Developmental and Behavioral Pediatrics, the First Hospital of Jilin University, Changchun, China
| | - Honghua Li
- Department of Developmental and Behavioral Pediatrics, the First Hospital of Jilin University, Changchun, China
| | - Chunyue Miao
- Department of Developmental and Behavioral Pediatrics, the First Hospital of Jilin University, Changchun, China
| | - Zhida Xu
- Department of Psychiatry, University Medical Center Utrecht, Netherlands
| | - Ching-Po Lin
- Neurological Research Center of First Hospital of Jilin University, Changchun, China; Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Khaled Saad
- Department of Developmental and Behavioral Pediatrics, the First Hospital of Jilin University, Changchun, China; Department of Pediatrics, Faculty of Medicine, Assiut University, Assiut, Egypt.
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Trifonova EA, Khlebodarova TM, Gruntenko NE. Molecular mechanisms of autism as a form of synaptic dysfunction. ACTA ACUST UNITED AC 2017. [DOI: 10.1134/s2079059717080020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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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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Bauman MD, Schumann CM. Advances in nonhuman primate models of autism: Integrating neuroscience and behavior. Exp Neurol 2017; 299:252-265. [PMID: 28774750 DOI: 10.1016/j.expneurol.2017.07.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/27/2017] [Accepted: 07/30/2017] [Indexed: 12/28/2022]
Abstract
Given the prevalence and societal impact of autism spectrum disorders (ASD), there is an urgent need to develop innovative preventative strategies and treatments to reduce the alarming number of cases and improve core symptoms for afflicted individuals. Translational efforts between clinical and preclinical research are needed to (i) identify and evaluate putative causes of ASD, (ii) determine the underlying neurobiological mechanisms, (iii) develop and test novel therapeutic approaches and (iv) ultimately translate basic research into safe and effective clinical practices. However, modeling a uniquely human brain disorder, such as ASD, will require sophisticated animal models that capitalize on unique advantages of diverse species including drosophila, zebra fish, mice, rats, and ultimately, species more closely related to humans, such as the nonhuman primate. Here we discuss the unique contributions of the rhesus monkey (Macaca mulatta) model to ongoing efforts to understand the neurobiology of the disorder, focusing on the convergence of brain and behavior outcome measures that parallel features of human ASD.
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Affiliation(s)
- M D Bauman
- The UC Davis MIND Institute, University of California, Davis, USA; Department of Psychiatry and Behavioral Sciences, University of California, Davis, USA; California National Primate Research Center, University of California, Davis, USA.
| | - C M Schumann
- The UC Davis MIND Institute, University of California, Davis, USA; Department of Psychiatry and Behavioral Sciences, University of California, Davis, USA
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Dórea JG. Low-dose Thimerosal in pediatric vaccines: Adverse effects in perspective. ENVIRONMENTAL RESEARCH 2017; 152:280-293. [PMID: 27816865 DOI: 10.1016/j.envres.2016.10.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 10/26/2016] [Accepted: 10/27/2016] [Indexed: 06/06/2023]
Abstract
Vaccines are prophylactics used as the first line of intervention to prevent, control and eradicate infectious diseases. Young children (before the age of six months) are the demographic group most exposed to recommended/mandatory vaccines preserved with Thimerosal and its metabolite ethylmercury (EtHg). Particularly in the less-developed countries, newborns, neonates, and young children are exposed to EtHg because it is still in several of their pediatric vaccines and mothers are often immunized with Thimerosal-containing vaccines (TCVs) during pregnancy. While the immunogenic component of the product has undergone more rigorous testing, Thimerosal, known to have neurotoxic effects even at low doses, has not been scrutinized for the limit of tolerance alone or in combination with adjuvant-Al during immaturity or developmental periods (pregnant women, newborns, infants, and young children). Scientific evidence has shown the potential hazards of Thimerosal in experiments that modeled vaccine-EtHg concentrations. Observational population studies have revealed uncertainties related to neurological effects. However, consistently, they showed a link of EtHg with risk of certain neurodevelopment disorders, such as tic disorder, while clearly revealing the benefits of removing Thimerosal from children's vaccines (associated with immunological reactions) in developed countries. So far, only rich countries have benefited from withdrawing the risk of exposing young children to EtHg. Regarding Thimerosal administered to the very young, we have sufficient studies that characterize a state of uncertainty: the collective evidence strongly suggests that Thimerosal exposure is associated with adverse neurodevelopmental outcomes. It is claimed that the continued use of Thimerosal in the less-developed countries is due to the cost to change to another preservative, such as 2-phenoxyethanol. However, the estimated cost increase per child in the first year of life is lower than estimated lifetime cost of caring for a child with a neurodevelopmental disorder, such tic disorder. The evidence indicates that Thimerosal-free vaccine options should be made available in developing countries.
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Affiliation(s)
- José G Dórea
- Professor Emeritus, Faculty of Health Sciences, Universidade de Brasilia, 70919-970 Brasilia, DF, Brazil.
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