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Stojsavljević A, Lakićević N, Pavlović S. Does Lead Have a Connection to Autism? A Systematic Review and Meta-Analysis. TOXICS 2023; 11:753. [PMID: 37755763 PMCID: PMC10536388 DOI: 10.3390/toxics11090753] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/20/2023] [Accepted: 08/31/2023] [Indexed: 09/28/2023]
Abstract
Environmental pollutants, particularly toxic trace metals with neurotoxic potential, have been related to the genesis of autism. One of these metals that stands out, in particular, is lead (Pb). We conducted an in-depth systematic review and meta-analysis of peer-reviewed studies on Pb levels in biological materials retrieved from autistic children (cases) and neurotypical children (controls) in this work. A systematic review was conducted after the careful selection of published studies according to established criteria to gain a broad insight into the higher or lower levels of Pb in the biological materials of cases and controls, and the findings were then strengthened by a meta-analysis. The meta-analysis included 17 studies (hair), 13 studies (whole blood), and 8 studies (urine). The overall number of controls/cases was 869/915 (hair), 670/755 (whole blood), and 344/373 (urine). This meta-analysis showed significantly higher Pb levels in all three types of biological material in cases than in controls, suggesting a higher body Pb burden in autistic children. Thus, environmental Pb exposure could be related to the genesis of autism. Since no level of Pb can be considered safe, the data from this study undoubtedly point to the importance of regularly monitoring Pb levels in autistic children.
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Affiliation(s)
- Aleksandar Stojsavljević
- Innovative Centre, Faculty of Chemistry, University of Belgrade, Studentski Trg 12–16, 11000 Belgrade, Serbia
| | - Novak Lakićević
- Clinical Centre of Montenegro, Clinic for Neurosurgery, Ljubljanska bb, 81000 Podgorica, Montenegro;
| | - Slađan Pavlović
- Institute for Biological Research “Siniša Stanković”—National Institute of the Republic of Serbia, University of Belgrade, Bulevar Despota Stefana 142, 11060 Belgrade, Serbia;
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Nakhaee S, Amirabadizadeh A, Farnia V, Ali Azadi N, Mansouri B, Radmehr F. Association Between Biological Lead Concentrations and Autism Spectrum Disorder (ASD) in Children: a Systematic Review and Meta-Analysis. Biol Trace Elem Res 2023; 201:1567-1581. [PMID: 35499802 DOI: 10.1007/s12011-022-03265-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 04/25/2022] [Indexed: 11/24/2022]
Abstract
Studies have been conducted in different countries of the world to illustrate a link between autism spectrum disorder (ASD) and lead (Pb) in different specimens such as hair, blood, and urine. Therefore, we carried out a systematic review and meta-analysis to determine the association between Pb concentration in biological samples (blood, urine, and hair) and ASD in children through case-control and cross-sectional studies. In this systematic review, PubMed, Web of Sciences, Scopus, and Google Scholar were searched for relevant studies from January 2000 to February 2022. A random-effects model was used to pool the results. The effect sizes were standardized mean differences (proxied by Hedges' g) followed by a 95% confidence interval. Pooling data under the random effect model from blood and hair studies showed a significant difference between the children in the ASD group and the control group in blood lead level (Hedges' g: 1.21, 95% CI: 0.33-2.09, P = 0.01) and hair level (Hedges' g: 2.20, 95% CI: 0.56-3.85, P = 0.01). For urine studies, pooling data under the random effect model from eight studies indicated no significant difference between the children in the ASD group and control group in urinary lead level (Hedges' g: - 0.34, 95% CI: - 1.14,0.45, P = 0.40). Moreover, the funnel plot and the results of the Egger test for the blood and urine samples showed no publication bias, while, for the hair samples, the funnel plot illustrated the existence of publication bias.
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Affiliation(s)
- Samaneh Nakhaee
- Medical Toxicology and Drug Abuse Research Center (MTDRC), Birjand University of Medical Sciences, Birjand, Iran
| | - Alireza Amirabadizadeh
- Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, 9717113163, Iran
| | - Vahid Farnia
- Substance Abuse Prevention Research Center, Research Institute for Health, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Nemam Ali Azadi
- Biostatistics Department, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Borhan Mansouri
- Substance Abuse Prevention Research Center, Research Institute for Health, Kermanshah University of Medical Sciences, Kermanshah, Iran.
| | - Farnaz Radmehr
- Substance Abuse Prevention Research Center, Research Institute for Health, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Hess JL, Quinn TP, Zhang C, Hearn GC, Chen S, Kong SW, Cairns M, Tsuang MT, Faraone SV, Glatt SJ. BrainGENIE: The Brain Gene Expression and Network Imputation Engine. Transl Psychiatry 2023; 13:98. [PMID: 36949060 PMCID: PMC10033657 DOI: 10.1038/s41398-023-02390-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 02/23/2023] [Accepted: 02/28/2023] [Indexed: 03/24/2023] Open
Abstract
In vivo experimental analysis of human brain tissue poses substantial challenges and ethical concerns. To address this problem, we developed a computational method called the Brain Gene Expression and Network-Imputation Engine (BrainGENIE) that leverages peripheral-blood transcriptomes to predict brain tissue-specific gene-expression levels. Paired blood-brain transcriptomic data collected by the Genotype-Tissue Expression (GTEx) Project was used to train BrainGENIE models to predict gene-expression levels in ten distinct brain regions using whole-blood gene-expression profiles. The performance of BrainGENIE was compared to PrediXcan, a popular method for imputing gene expression levels from genotypes. BrainGENIE significantly predicted brain tissue-specific expression levels for 2947-11,816 genes (false-discovery rate-adjusted p < 0.05), including many transcripts that cannot be predicted significantly by a transcriptome-imputation method such as PrediXcan. BrainGENIE recapitulated measured diagnosis-related gene-expression changes in the brain for autism, bipolar disorder, and schizophrenia better than direct correlations from blood and predictions from PrediXcan. We developed a convenient software toolset for deploying BrainGENIE, and provide recommendations for how best to implement models. BrainGENIE complements and, in some ways, outperforms existing transcriptome-imputation tools, providing biologically meaningful predictions and opening new research avenues.
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Affiliation(s)
- Jonathan L Hess
- Department of Psychiatry & Behavioral Sciences, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA
| | - Thomas P Quinn
- Applied Artificial Intelligence Institute (A2I2), Deakin University, Geelong, Australia
| | - Chunling Zhang
- Department of Neuroscience & Physiology, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA
| | - Gentry C Hearn
- Department of Neuroscience & Physiology, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA
| | - Samuel Chen
- Department of Psychiatry & Behavioral Sciences, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA
| | - Sek Won Kong
- Computational Health Informatics Program, Boston Children's Hospital, Boston, MA, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Murray Cairns
- School of Biomedical Sciences & Pharmacy, Faculty of Health, The University of Newcastle, New South Wales, Callaghan, New South Wales, Australia
- Hunter Medical Research Institute, Newcastle, Australia
- Centre for Brain & Mental Health Research, The University of Newcastle, Callaghan, Australia
| | - Ming T Tsuang
- Center for Behavioral Genomics, Department of Psychiatry, Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA, USA
- Harvard Institute of Psychiatric Epidemiology and Genetics, Boston, MA, USA
| | - Stephen V Faraone
- Department of Psychiatry & Behavioral Sciences, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA
- Department of Neuroscience & Physiology, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA
| | - Stephen J Glatt
- Department of Psychiatry & Behavioral Sciences, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA.
- Department of Neuroscience & Physiology, Norton College of Medicine at SUNY Upstate Medical University, Syracuse, NY, USA.
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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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Integrative analysis to explore the biological association between environmental skin diseases and ambient particulate matter. Sci Rep 2022; 12:9750. [PMID: 35697899 PMCID: PMC9192598 DOI: 10.1038/s41598-022-13001-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 04/18/2022] [Indexed: 12/14/2022] Open
Abstract
Although numerous experimental studies have suggested a significant association between ambient particulate matter (PM) and respiratory damage, the etiological relationship between ambient PM and environmental skin diseases is not clearly understood. Here, we aimed to explore the association between PM and skin diseases through biological big data analysis. Differential gene expression profiles associated with PM and environmental skin diseases were retrieved from public genome databases. The co-expression among them was analyzed using a text-mining-based network analysis software. Activation/inhibition patterns from RNA-sequencing data performed with PM2.5-treated normal human epidermal keratinocytes (NHEK) were overlapped to select key regulators of the analyzed pathways. We explored the adverse effects of PM on the skin and attempted to elucidate their relationships using public genome data. We found that changes in upstream regulators and inflammatory signaling networks mediated by MMP-1, MMP-9, PLAU, S100A9, IL-6, and S100A8 were predicted as the key pathways underlying PM-induced skin diseases. Our integrative approach using a literature-based co-expression analysis and experimental validation not only improves the reliability of prediction but also provides assistance to clarify underlying mechanisms of ambient PM-induced dermal toxicity that can be applied to screen the relationship between other chemicals and adverse effects.
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Detoxification Role of Metabolic Glutathione S-Transferase (GST) Genes in Blood Lead Concentrations of Jamaican Children with and without Autism Spectrum Disorder. Genes (Basel) 2022; 13:genes13060975. [PMID: 35741737 PMCID: PMC9222697 DOI: 10.3390/genes13060975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/09/2022] [Accepted: 05/27/2022] [Indexed: 12/04/2022] Open
Abstract
Glutathione S-transferases (GST) are involved in the detoxification of exogenous chemicals including lead (Pb). Using data from 344 pairs of autism spectrum disorder (ASD) cases and age- and sex-matched typically developing (TD) controls (2−8 years old) from Jamaica, we investigated the interaction between three GST genes and ASD status as determinants of blood Pb concentrations (BPbCs). We found that ASD cases had lower geometric mean BPbCs than TD children (1.74 vs. 2.27 µg/dL, p < 0.01). Using a co-dominant genetic model, ASD cases with the Ile/Val genotype for the GSTP1 Ile105Val polymorphism had lower GM BPbCs than TD controls, after adjusting for a known interaction between GSTP1 and GSTT1, child’s parish, socioeconomic status, consumption of lettuce, fried plantains, and canned fish (Ile/Val: 1.78 vs. 2.13 µg/dL, p = 0.03). Similarly, among carriers of the I/I or I/D (I*) genotype for GSTT1 and GSTM1, ASD cases had lower adjusted GM BPbCs than TD controls (GSTT1 I*: 1.61 vs. 1.91 µg/dL, p = 0.01; GSTM1 I*: 1.71 vs. 2.04 µg/dL, p = 0.01). Our findings suggest that genetic polymorphisms in GST genes may influence detoxification of Pb by the enzymes they encode in Jamaican children with and without ASD.
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New Horizons for Molecular Genetics Diagnostic and Research in Autism Spectrum Disorder. ADVANCES IN NEUROBIOLOGY 2020; 24:43-81. [PMID: 32006356 DOI: 10.1007/978-3-030-30402-7_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Autism spectrum disorder (ASD) is a highly heritable, heterogeneous, and complex pervasive neurodevelopmental disorder (PND) characterized by distinctive abnormalities of human cognitive functions, social interaction, and speech development.Nowadays, several genetic changes including chromosome abnormalities, genetic variations, transcriptional epigenetics, and noncoding RNA have been identified in ASD. However, the association between these genetic modifications and ASDs has not been confirmed yet.The aim of this review is to summarize the key findings in ASD from genetic viewpoint that have been identified from the last few decades of genetic and molecular research.
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Mordaunt CE, Park BY, Bakulski KM, Feinberg JI, Croen LA, Ladd-Acosta C, Newschaffer CJ, Volk HE, Ozonoff S, Hertz-Picciotto I, LaSalle JM, Schmidt RJ, Fallin MD. A meta-analysis of two high-risk prospective cohort studies reveals autism-specific transcriptional changes to chromatin, autoimmune, and environmental response genes in umbilical cord blood. Mol Autism 2019; 10:36. [PMID: 31673306 PMCID: PMC6814108 DOI: 10.1186/s13229-019-0287-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 09/08/2019] [Indexed: 12/17/2022] Open
Abstract
Background Autism spectrum disorder (ASD) is a neurodevelopmental disorder that affects more than 1% of children in the USA. ASD risk is thought to arise from both genetic and environmental factors, with the perinatal period as a critical window. Understanding early transcriptional changes in ASD would assist in clarifying disease pathogenesis and identifying biomarkers. However, little is known about umbilical cord blood gene expression profiles in babies later diagnosed with ASD compared to non-typically developing and non-ASD (Non-TD) or typically developing (TD) children. Methods Genome-wide transcript levels were measured by Affymetrix Human Gene 2.0 array in RNA from cord blood samples from both the Markers of Autism Risk in Babies-Learning Early Signs (MARBLES) and the Early Autism Risk Longitudinal Investigation (EARLI) high-risk pregnancy cohorts that enroll younger siblings of a child previously diagnosed with ASD. Younger siblings were diagnosed based on assessments at 36 months, and 59 ASD, 92 Non-TD, and 120 TD subjects were included. Using both differential expression analysis and weighted gene correlation network analysis, gene expression between ASD and TD, and between Non-TD and TD, was compared within each study and via meta-analysis. Results While cord blood gene expression differences comparing either ASD or Non-TD to TD did not reach genome-wide significance, 172 genes were nominally differentially expressed between ASD and TD cord blood (log2(fold change) > 0.1, p < 0.01). These genes were significantly enriched for functions in xenobiotic metabolism, chromatin regulation, and systemic lupus erythematosus (FDR q < 0.05). In contrast, 66 genes were nominally differentially expressed between Non-TD and TD, including 8 genes that were also differentially expressed in ASD. Gene coexpression modules were significantly correlated with demographic factors and cell type proportions. Limitations ASD-associated gene expression differences identified in this study are subtle, as cord blood is not the main affected tissue, it is composed of many cell types, and ASD is a heterogeneous disorder. Conclusions This is the first study to identify gene expression differences in cord blood specific to ASD through a meta-analysis across two prospective pregnancy cohorts. The enriched gene pathways support involvement of environmental, immune, and epigenetic mechanisms in ASD etiology.
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Affiliation(s)
- Charles E Mordaunt
- 1Department of Medical Microbiology and Immunology, Genome Center, and MIND Institute, University of California, Davis, CA USA
| | - Bo Y Park
- 2Department of Public Health, California State University, Fullerton, CA USA
| | - Kelly M Bakulski
- 3Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI USA
| | - Jason I Feinberg
- 4Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD USA
| | - Lisa A Croen
- 5Division of Research and Autism Research Program, Kaiser Permanente Northern California, Oakland, CA USA
| | | | - Craig J Newschaffer
- 6Department of Biobehavioral Health, College of Health and Human Development, Pennsylvania State University, University Park, PA USA
| | - Heather E Volk
- 4Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD USA
| | - Sally Ozonoff
- 7Psychiatry and Behavioral Sciences and MIND Institute, University of California, Davis, CA USA
| | - Irva Hertz-Picciotto
- 8Department of Public Health Sciences and MIND Institute, University of California, Davis, CA USA
| | - Janine M LaSalle
- 1Department of Medical Microbiology and Immunology, Genome Center, and MIND Institute, University of California, Davis, CA USA
| | - Rebecca J Schmidt
- 8Department of Public Health Sciences and MIND Institute, University of California, Davis, CA USA
| | - M Daniele Fallin
- 4Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD USA
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Wang M, Hossain F, Sulaiman R, Ren X. Exposure to Inorganic Arsenic and Lead and Autism Spectrum Disorder in Children: A Systematic Review and Meta-Analysis. Chem Res Toxicol 2019; 32:1904-1919. [PMID: 31549506 DOI: 10.1021/acs.chemrestox.9b00134] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Inorganic arsenic (iAs) and lead (Pb) rank first and second on the U.S. Environmental Protection Agency's priority list of hazardous substances. Both are known neurotoxic metals that cause detrimental effects on brain development and lead to deficits in cognitive function and behavioral performance in children. Studies have indicated a potential link between iAs and Pb exposure and a higher risk for autism spectrum disorder (ASD). To provide further insight into whether developmental exposure to iAs or Pb is associated with ASD, we conducted a systematic review and combined data into a meta-analysis to evaluate the available human evidence on the relationships. We systematically reviewed relevant studies published through December 30, 2018 and identified 14 studies on iAs and 37 studies on Pb exposure and their respective associations with ASD. Among them, 8 (53.3%) and 19 (51.3%) studies reported a positive association for iAs and Pb, respectively, and none reported a sole inverse association. In the following meta-analysis, we found statistically significant higher iAs concentrations, in hair and in blood, for children diagnosed with ASD compared with controls across studies. However, the findings on Pb exposure were inconsistent, with a significant association for hair Pb, no association for urinary Pb, and an inverse association for blood Pb. After considering strengths and limitations of the body of research, we concluded that there is consistent evidence supporting a positive association between early life iAs exposure and diagnosis of ASD and inconsistent evidence for Pb exposure and ASD risk. We believe it is in the best interest of policy makers and the public to reduce exposures to iAs and Pb among pregnant women and children. Further, our research supports the need for large perspective human studies with accurate measurement and determination of the long-term body burden of iAs and Pb exposures to assess the impact of iAs and Pb exposures on ASD risk.
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Affiliation(s)
- Meng Wang
- Research and Education in Energy, Environment and Water Institute , University at Buffalo , Buffalo , New York 14260 , United States
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Hessabi M, Rahbar MH, Dobrescu I, Bach MA, Kobylinska L, Bressler J, Grove ML, Loveland KA, Mihailescu I, Nedelcu MC, Moisescu MG, Matei BM, Matei CO, Rad F. Concentrations of Lead, Mercury, Arsenic, Cadmium, Manganese, and Aluminum in Blood of Romanian Children Suspected of Having Autism Spectrum Disorder. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:E2303. [PMID: 31261817 PMCID: PMC6651707 DOI: 10.3390/ijerph16132303] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 06/24/2019] [Accepted: 06/25/2019] [Indexed: 12/15/2022]
Abstract
Environmental exposure to lead (Pb), mercury (Hg), arsenic (As), cadmium (Cd), manganese (Mn), and aluminum (Al) has been associated with neurodevelopmental disorders including autism spectrum disorder (ASD). We conducted a pilot study during May 2015-May 2107 to estimate blood concentrations of six metals (Pb, Hg, As, Cd, Mn, and Al) and identify their associated factors for children with ASD or suspected of having ASD in Romania. Sixty children, age 2-8 years, were administered versions of ADOS or ADI-R translated from English to Romanian. After assessment, 2-3 mL of blood was obtained and analyzed for the concentrations of the six metals. The mean age of children was 51.9 months and about 90% were male. More than half (65%) of the children were born in Bucharest. Over 90% of concentrations of As and Cd were below limits of detection. Geometric mean concentrations of Pb, Mn, Al, and Hg were 1.14 μg/dL, 10.84 μg/L, 14.44 μg/L, and 0.35 μg/L, respectively. Multivariable linear regression analysis revealed that children who were female, had less educated parents, exhibited pica, and ate cold breakfast (e.g., cereal), watermelon, and lamb had significantly higher concentrations of Pb compared to their respective referent categories (all p < 0.05 except for eating lamb, which was marginally significant, p = 0.053). Although this is the first study that provides data on concentrations of the six metals for Romanian children with ASD, the findings from this study could be useful for designing future epidemiologic studies for investigating the role of these six metals in ASD in Romanian children.
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Affiliation(s)
- Manouchehr Hessabi
- Biostatistics/Epidemiology/Research Design (BERD) core, Center for Clinical and Translational Sciences (CCTS), The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Mohammad H Rahbar
- Biostatistics/Epidemiology/Research Design (BERD) core, Center for Clinical and Translational Sciences (CCTS), The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Division of Clinical and Translational Sciences, Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Iuliana Dobrescu
- Department of Child and Adolescent Psychiatry, University of Medicine and Pharmacy of Carol Davila, Psychiatry Clinical Hospital Alexandru Obregia, Bucharest, sector 4, 041914, Romania
| | - MacKinsey A Bach
- Biostatistics/Epidemiology/Research Design (BERD) core, Center for Clinical and Translational Sciences (CCTS), The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Liana Kobylinska
- Department of Child and Adolescent Psychiatry, University of Medicine and Pharmacy of Carol Davila, Psychiatry Clinical Hospital Alexandru Obregia, Bucharest, sector 4, 041914, Romania
| | - Jan Bressler
- Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Megan L Grove
- Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Human Genetics Center, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Katherine A Loveland
- Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX 77054, USA
| | - Ilinca Mihailescu
- Department of Child and Adolescent Psychiatry, University of Medicine and Pharmacy of Carol Davila, Psychiatry Clinical Hospital Alexandru Obregia, Bucharest, sector 4, 041914, Romania
| | - Maria Cristina Nedelcu
- Department of Child and Adolescent Psychiatry, University of Medicine and Pharmacy of Carol Davila, Psychiatry Clinical Hospital Alexandru Obregia, Bucharest, sector 4, 041914, Romania
| | - Mihaela Georgeta Moisescu
- Department of Biophysics and Cellular Biotechnology, University of Medicine and Pharmacy of Carol Davila, Bucharest, sector 5, 050747, Romania
| | - Bogdan Mircea Matei
- Department of Biophysics and Cellular Biotechnology, University of Medicine and Pharmacy of Carol Davila, Bucharest, sector 5, 050747, Romania
| | - Christien Oktaviani Matei
- Department of Biophysics and Cellular Biotechnology, University of Medicine and Pharmacy of Carol Davila, Bucharest, sector 5, 050747, Romania
| | - Florina Rad
- Department of Child and Adolescent Psychiatry, University of Medicine and Pharmacy of Carol Davila, Psychiatry Clinical Hospital Alexandru Obregia, Bucharest, sector 4, 041914, Romania.
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Wu J, Liu DJ, Shou XJ, Zhang JS, Meng FC, Liu YQ, Han SP, Zhang R, Jia JZ, Wang JY, Han JS. Chinese children with autism: A multiple chemical elements profile in erythrocytes. Autism Res 2018; 11:834-845. [DOI: 10.1002/aur.1949] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 01/31/2018] [Accepted: 02/19/2018] [Indexed: 01/20/2023]
Affiliation(s)
- Jing Wu
- Neuroscience Research Institute, Peking University; Beijing PR China
- Key Laboratory for Neuroscience, Ministry of Education of China; Peking University; Beijing PR China
- Key Laboratory for Neuroscience, National Committee of Health and Family Planning of China; Peking University; Beijing PR China
- Department of Neurobiology, School of Basic Medical Sciences; Peking University; Beijing PR China
| | - Duo-Jian Liu
- School of Public Health, Peking University; Beijing PR China
| | - Xiao-Jing Shou
- Neuroscience Research Institute, Peking University; Beijing PR China
- Key Laboratory for Neuroscience, Ministry of Education of China; Peking University; Beijing PR China
- Key Laboratory for Neuroscience, National Committee of Health and Family Planning of China; Peking University; Beijing PR China
- Department of Neurobiology, School of Basic Medical Sciences; Peking University; Beijing PR China
| | - Ji-Shui Zhang
- Department of Neurology; Beijing Children's Hospital Affiliated Capital Medical University; Beijing PR China
| | - Fan-Chao Meng
- Neuroscience Research Institute, Peking University; Beijing PR China
- Key Laboratory for Neuroscience, Ministry of Education of China; Peking University; Beijing PR China
- Key Laboratory for Neuroscience, National Committee of Health and Family Planning of China; Peking University; Beijing PR China
- Department of Neurobiology, School of Basic Medical Sciences; Peking University; Beijing PR China
| | - Ya-Qiong Liu
- School of Public Health, Peking University; Beijing PR China
| | - Song-Ping Han
- Neuroscience Research Institute, Peking University; Beijing PR China
- Key Laboratory for Neuroscience, Ministry of Education of China; Peking University; Beijing PR China
- Key Laboratory for Neuroscience, National Committee of Health and Family Planning of China; Peking University; Beijing PR China
- Department of Neurobiology, School of Basic Medical Sciences; Peking University; Beijing PR China
| | - Rong Zhang
- Neuroscience Research Institute, Peking University; Beijing PR China
- Key Laboratory for Neuroscience, Ministry of Education of China; Peking University; Beijing PR China
- Key Laboratory for Neuroscience, National Committee of Health and Family Planning of China; Peking University; Beijing PR China
- Department of Neurobiology, School of Basic Medical Sciences; Peking University; Beijing PR China
| | - Jin-Zhu Jia
- School of Public Health, Peking University; Beijing PR China
- Center of Statistical Science, Peking University; Beijing PR China
| | - Jing-Yu Wang
- School of Public Health, Peking University; Beijing PR China
| | - Ji-Sheng Han
- Neuroscience Research Institute, Peking University; Beijing PR China
- Key Laboratory for Neuroscience, Ministry of Education of China; Peking University; Beijing PR China
- Key Laboratory for Neuroscience, National Committee of Health and Family Planning of China; Peking University; Beijing PR China
- Department of Neurobiology, School of Basic Medical Sciences; Peking University; Beijing PR China
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Dickerson AS, Rotem RS, Christian MA, Nguyen VT, Specht AJ. Potential Sex Differences Relative to Autism Spectrum Disorder and Metals. Curr Environ Health Rep 2018; 4:405-414. [PMID: 28988324 DOI: 10.1007/s40572-017-0164-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
PURPOSE OF REVIEW This study aims to summarize the current body of literature on the relationship between various toxic metals exposures (i.e., aluminum, antimony, arsenic, beryllium, cadmium, chromium, lead, manganese, and nickel) and autism spectrum disorder (ASD), with a focus on potential sex differences in these associations. RECENT FINDINGS Sex differences in ASD diagnosis and mutagenic effects of toxic exposures indicate that sex differences may play a major part in the causal relationship of any potential associations seen; however, we were only able to find three studies that reported on sex differences in observed associations with toxic metals exposure and ASD. We also found several studies investigating associations between ASD and metals exposures, including 11 on aluminum, 6 on antimony, 15 on arsenic, 5 on beryllium, 17 on cadmium, 11 on chromium, 25 on lead, 14 on manganese, and 13 on nickel with markers of exposure in hair, urine, blood, teeth, fingernails, and air pollution. Results for each metal were conflicting, but studies on cadmium and lead yielded the highest proportion of studies with positive results (72% and 36%, respectively). Based on our examination of existing literature, the current evidence warrants a considerable need for evaluations of sex differences in future studies assessing the association between metals exposures and ASD. Additionally, failure to account for potential sex differences could result in bias and misinterpretation of exposure-disease relationships.
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Affiliation(s)
- Aisha S Dickerson
- Departments of Epidemiology and Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, 02215, USA. .,Environmental and Occupation Medicine and Epidemiology Division of the Department of Environmental Health, Harvard T.H. Chan School of Public Health, 401 Park Street, Landmark Center L3-125, Boston, MA, USA.
| | - Ran S Rotem
- Department Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, 02215, USA
| | - MacKinsey A Christian
- Division of Epidemiology, Human Genetics and Environmental Sciences, School of Public Health, and Center for Clinical and Translational Sciences (CCTS), University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Vy T Nguyen
- Department Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, 02215, USA
| | - Aaron J Specht
- Department Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, 02215, USA
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13
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Li H, Li H, Li Y, Liu Y, Zhao Z. Blood Mercury, Arsenic, Cadmium, and Lead in Children with Autism Spectrum Disorder. Biol Trace Elem Res 2018; 181:31-37. [PMID: 28480499 DOI: 10.1007/s12011-017-1002-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 03/17/2017] [Indexed: 12/15/2022]
Abstract
Environmental factors have been implicated in the etiology of autism spectrum disorder (ASD); however, the role of heavy metals has not been fully defined. This study investigated whether blood levels of mercury, arsenic, cadmium, and lead of children with ASD significantly differ from those of age- and sex-matched controls. One hundred eighty unrelated children with ASD and 184 healthy controls were recruited. Data showed that the children with ASD had significantly (p < 0.001) higher levels of mercury and arsenic and a lower level of cadmium. The levels of lead did not differ significantly between the groups. The results of this study are consistent with numerous previous studies, supporting an important role for heavy metal exposure, particularly mercury, in the etiology of ASD. It is desirable to continue future research into the relationship between ASD and heavy metal exposure.
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Affiliation(s)
- Huamei Li
- Children's Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Hui Li
- Laboratory of Neuroinflammation, StVincent's Centre for Applied Medical Research and University of New South Wales, Sydney, NSW, Australia
| | - Yun Li
- Children's Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Yujie Liu
- Children's Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Zhengyan Zhao
- Children's Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China.
- Department of Pediatric Health Care, Children's Hospital of Zhejiang University School of Medicine, 57 Zhuganxiang Road, Hangzhou, People's Republic of China, 310003.
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Saghazadeh A, Rezaei N. Systematic review and meta-analysis links autism and toxic metals and highlights the impact of country development status: Higher blood and erythrocyte levels for mercury and lead, and higher hair antimony, cadmium, lead, and mercury. Prog Neuropsychopharmacol Biol Psychiatry 2017; 79:340-368. [PMID: 28716727 DOI: 10.1016/j.pnpbp.2017.07.011] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder that affects cognitive and higher cognitive functions. Increasing prevalence of ASD and high rates of related comorbidities has caused serious health loss and placed an onerous burden on the supporting families, caregivers, and health care services. Heavy metals are among environmental factors that may contribute to ASD. However, due to inconsistencies across studies, it is still hard to explain the association between ASD and toxic metals. Therefore the objective of this study was to investigate the difference in heavy metal measures between patients with ASD and control subjects. METHODS We included observational studies that measured levels of toxic metals (antimony, arsenic, cadmium, lead, manganese, mercury, nickel, silver, and thallium) in different specimens (whole blood, plasma, serum, red cells, hair and urine) for patients with ASD and for controls. The main electronic medical database (PubMed and Scopus) were searched from inception through October 2016. RESULTS 52 studies were eligible to be included in the present systematic review, of which 48 studies were included in the meta-analyses. The hair concentrations of antimony (standardized mean difference (SMD)=0.24; 95% confidence interval (CI): 0.03 to 0.45) and lead (SMD=0.60; 95% confidence interval (CI): 0.17 to 1.03) in ASD patients were significantly higher than those of control subjects. ASD patients had higher erythrocyte levels of lead (SMD=1.55, CI: 0.2 to 2.89) and mercury (SMD=1.56, CI: 0.42 to 2.70). There were significantly higher blood lead levels in ASD patients (SMD=0.43, CI: 0.02 to 0.85). Sensitivity analyses showed that ASD patients in developed but not in developing countries have lower hair concentrations of cadmium (SMD=-0.29, CI: -0.46 to -0.12). Also, such analyses indicated that ASD patients in developing but not in developed lands have higher hair concentrations of lead (SMD=1.58, CI: 0.80 to 2.36) and mercury (SMD=0.77, CI: 0.31 to 1.23). These findings were confirmed by meta-regression analyses indicating that development status of countries significantly influences the overall effect size of mean difference for hair arsenic, cadmium, lead, and mercury between patients with ASD and controls. CONCLUSION The findings help highlighting the role of toxic metals as environmental factors in the etiology of ASD, especially in developing lands. While there are environmental factors other than toxic metals that greatly contribute to the etiology of ASD in developed lands. It would be, thus, expected that classification of ASD includes etiological entities of ASD on the basis of implication of industrial pollutants (developed vs. developing ASD).
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Affiliation(s)
- Amene Saghazadeh
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; MetaCognition Interest Group (MCIG), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Systematic Review and Meta-analysis Expert Group (SRMEG), Universal Scientific Education and Research Network (USERN), Boston, MA, USA.
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15
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El-Ansary A, Bjørklund G, Tinkov AA, Skalny AV, Al Dera H. Relationship between selenium, lead, and mercury in red blood cells of Saudi autistic children. Metab Brain Dis 2017; 32:1073-1080. [PMID: 28326463 DOI: 10.1007/s11011-017-9996-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/15/2017] [Indexed: 12/22/2022]
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder that can cause significant social, communication and behavioral challenges. Environmental contribution to ASD is due in large part to the sensitivity of the developing brain to external exposures such as lead (Pb), and mercury (Hg) as toxic heavy metals or due to a poor detoxification ability as the phenotype of this disorder. Selenium (Se) as an antioxidant element that counteracts the neurotoxicity of Hg, and Pb, presumably through the formation of nontoxic complexes. In the present study, Pb, Hg, and Se were measured in red blood cells (RBCs) of 35 children with ASD and 30 age- and gender-matched healthy control children using atomic absorption spectrometry. Receiver Operating Characteristics (ROC) analysis of the obtained data was performed to measure the predictive value of their absolute and relative concentrations. The obtained data demonstrates a significant elevation of Hg and Pb together with a significant decrease in the Se levels in RBCs of patients with ASD when compared to the healthy controls. The ratios of Se to both Pb and Hg were remarkably altered, being indicative of heavy metal neurotoxicity in patients with ASD. In conclusion, the present study indicates the importance of Se for prevention and/or therapy of heavy metal neurotoxicity.
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Affiliation(s)
- Afaf El-Ansary
- Central Laboratory, Center for Female Scientific and Medical Colleges, King Saud University, Riyadh, Saudi Arabia
- Autism Research and Treatment Center, Riyadh, Saudi Arabia
- Medicinal Chemistry Department, National Research Centre, Dokki, Cairo, Egypt
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Toften 24, 8610, Mo i Rana, Norway.
| | - Alexey A Tinkov
- Orenburg State University, Orenburg, Russia
- Orenburg State Medical University, Orenburg, Russia
- Yaroslavl State University, Yaroslavl, Russia
| | - Anatoly V Skalny
- Orenburg State Medical University, Orenburg, Russia
- Yaroslavl State University, Yaroslavl, Russia
- RUDN University, Moscow, Russia
- All-Russian Research Institute of Medicinal and Aromatic Plants, Moscow, Russia
| | - Hussain Al Dera
- Basic Medical Science Department, College of Medicine, King Saud bin Abdul Aziz University for Health Sciences, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Riyadh, Saudi Arabia
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Liu B, Zhang H, Tan X, Yang D, Lv Z, Jiang H, Lu J, Baiyun R, Zhang Z. GSPE reduces lead-induced oxidative stress by activating the Nrf2 pathway and suppressing miR153 and GSK-3β in rat kidney. Oncotarget 2017; 8:42226-42237. [PMID: 28178683 PMCID: PMC5522062 DOI: 10.18632/oncotarget.15033] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 01/16/2017] [Indexed: 01/27/2023] Open
Abstract
Lead (Pb) is a global environmental health hazard that leads to nephrotoxicity. However, the effective treatment of Pb-induced nephrotoxicity remains elusive. Grape seed procyanidin extract (GSPE) has beneficial properties for multiple biological functions. Therefore, the present study investigated whether GSPE reduced Pb-induced nephrotoxicity as well as the protective mechanism of GSPE in a well-established 35-day Pb induced nephrotoxicity rat model. The results showed that GSPE normalized Pb-induced oxidative stress, histological damage, inflammatory, apoptosis, and changes of miR153 and glycogen synthase kinase 3β (GSK-3β) levels in rat kidney. Moreover, GSPE enhanced the induction of phase II detoxifying enzymes (heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1) by increasing nuclear factor-erythroid-2-related factor 2 (Nrf2) expression. This study identifies for the first time that Pb-induced oxidative stress in rat kidney is attenuated by GSPE treatment via activating Nrf2 signaling pathway and suppressing miR153 and GSK-3β. Nrf2 signaling provides a new therapeutic target for renal injury induced by Pb, and GSPE could be a potential natural agent to protect against Pb-induced nephrotoxicity.
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Affiliation(s)
- Biying Liu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Haili Zhang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Xiao Tan
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Daqian Yang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Zhanjun Lv
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Huijie Jiang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Jingjing Lu
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Ruiqi Baiyun
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
| | - Zhigang Zhang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China
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Tylee DS, Hess JL, Quinn TP, Barve R, Huang H, Zhang-James Y, Chang J, Stamova BS, Sharp FR, Hertz-Picciotto I, Faraone SV, Kong SW, Glatt SJ. Blood transcriptomic comparison of individuals with and without autism spectrum disorder: A combined-samples mega-analysis. Am J Med Genet B Neuropsychiatr Genet 2017; 174:181-201. [PMID: 27862943 PMCID: PMC5499528 DOI: 10.1002/ajmg.b.32511] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 10/21/2016] [Indexed: 12/25/2022]
Abstract
Blood-based microarray studies comparing individuals affected with autism spectrum disorder (ASD) and typically developing individuals help characterize differences in circulating immune cell functions and offer potential biomarker signal. We sought to combine the subject-level data from previously published studies by mega-analysis to increase the statistical power. We identified studies that compared ex vivo blood or lymphocytes from ASD-affected individuals and unrelated comparison subjects using Affymetrix or Illumina array platforms. Raw microarray data and clinical meta-data were obtained from seven studies, totaling 626 affected and 447 comparison subjects. Microarray data were processed using uniform methods. Covariate-controlled mixed-effect linear models were used to identify gene transcripts and co-expression network modules that were significantly associated with diagnostic status. Permutation-based gene-set analysis was used to identify functionally related sets of genes that were over- and under-expressed among ASD samples. Our results were consistent with diminished interferon-, EGF-, PDGF-, PI3K-AKT-mTOR-, and RAS-MAPK-signaling cascades, and increased ribosomal translation and NK-cell related activity in ASD. We explored evidence for sex-differences in the ASD-related transcriptomic signature. We also demonstrated that machine-learning classifiers using blood transcriptome data perform with moderate accuracy when data are combined across studies. Comparing our results with those from blood-based studies of protein biomarkers (e.g., cytokines and trophic factors), we propose that ASD may feature decoupling between certain circulating signaling proteins (higher in ASD samples) and the transcriptional cascades which they typically elicit within circulating immune cells (lower in ASD samples). These findings provide insight into ASD-related transcriptional differences in circulating immune cells. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Daniel S. Tylee
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A
| | - Jonathan L. Hess
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A
| | - Thomas P. Quinn
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A
| | - Rahul Barve
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A
| | - Hailiang Huang
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Massachusetts, USA,Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Yanli Zhang-James
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A
| | - Jeffrey Chang
- Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, NY, U.S.A
| | - Boryana S. Stamova
- Department of Neurology, UC Davis School of Medicine, Sacramento, CA, USA
| | - Frank R. Sharp
- Department of Neurology, UC Davis School of Medicine, Sacramento, CA, USA
| | - Irva Hertz-Picciotto
- Department of Public Health Sciences and UC Davis MIND Institute, School of Medicine, Davis, CA
| | - Stephen V. Faraone
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A,K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, University of Bergen, Bergen, Norway
| | - Sek Won Kong
- Computational Health Informatics Program, Boston Children’s Hospital; Department of Pediatrics, Harvard Medical School, Boston, MA, U.S.A
| | - Stephen J. Glatt
- Psychiatric Genetic Epidemiology & Neurobiology Laboratory (PsychGENe Lab); Departments of Psychiatry and Behavioral Sciences & Neuroscience and Physiology; SUNY Upstate Medical University; Syracuse, NY, U.S.A,To whom correspondence should be addressed: SUNY Upstate Medical University, 750 East Adams Street, Syracuse, NY 13210, Phone: (315) 464-7742,
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18
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Ansel A, Rosenzweig JP, Zisman PD, Melamed M, Gesundheit B. Variation in Gene Expression in Autism Spectrum Disorders: An Extensive Review of Transcriptomic Studies. Front Neurosci 2017; 10:601. [PMID: 28105001 PMCID: PMC5214812 DOI: 10.3389/fnins.2016.00601] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 12/15/2016] [Indexed: 01/01/2023] Open
Abstract
Autism spectrum disorders (ASDs) are a group of complex neurodevelopmental conditions that present in early childhood and have a current estimated prevalence of about 1 in 68 US children, 1 in 42 boys. ASDs are heterogeneous, and arise from epigenetic, genetic and environmental origins, yet, the exact etiology of ASDs still remains unknown. Individuals with ASDs are characterized by having deficits in social interaction, impaired communication and a range of stereotyped and repetitive behaviors. Currently, a diagnosis of ASD is based solely on behavioral assessments and phenotype. Hundreds of diverse ASD susceptibility genes have been identified, yet none of the mutations found account for more than a small subset of autism cases. Therefore, a genetic diagnosis is not yet possible for the majority of the ASD population. The susceptibility genes that have been identified are involved in a wide and varied range of biological functions. Since the genetics of ASDs is so diverse, information on genome function as provided by transcriptomic data is essential to further our understanding. Gene expression studies have been extremely useful in comparing groups of individuals with ASD and control samples in order to measure which genes (or group of genes) are dysregulated in the ASD group. Transcriptomic studies are essential as a key link between measuring protein levels and analyzing genetic information. This review of recent autism gene expression studies highlights genes that are expressed in the brain, immune system, and processes such as cell metabolism and embryology. Various biological processes have been shown to be implicated with ASD individuals as well as differences in gene expression levels between different types of biological tissues. Some studies use gene expression to attempt to separate autism into different subtypes. An updated list of genes shown to be significantly dysregulated in individuals with autism from all recent ASD expression studies will help further research isolate any patterns useful for diagnosis or understanding the mechanisms involved. The functional relevance of transcriptomic studies as a method of classifying and diagnosing ASD cannot be underestimated despite the possible limitations of transcriptomic studies.
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19
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Taylor CM, Golding J, Emond AM. Moderate Prenatal Cadmium Exposure and Adverse Birth Outcomes: a Role for Sex-Specific Differences? Paediatr Perinat Epidemiol 2016; 30:603-611. [PMID: 27778365 PMCID: PMC5111596 DOI: 10.1111/ppe.12318] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND/AIM Studies on the effects of moderate prenatal exposure to cadmium (Cd) on birth outcomes have been contradictory and it has been suggested that effects may be partly masked by sex-specific effects. Our aim was to examine the association of Cd exposure in a large group of pregnant women with birth outcomes in the whole group of participants and by sex. METHODS Pregnant women were enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). Whole blood samples for singleton pregnancies with a live birth were analysed for Cd (n = 4191). Data collected on the infants included anthropometric variables and gestational age at delivery. Data were analysed using SPSS v18. RESULTS There were adverse associations of maternal blood Cd level with birthweight (unstandardized B coefficient -62.7 g, 95% CI -107.0, -18.4) and crown-heel length (-0.28 cm, 95% CI -0.48, -0.07) in adjusted regression models. On stratification by sex, maternal blood Cd level was adversely associated with birthweight (-87.1 g, 95% CI -144.8, -29.4), head circumference (-0.22 cm, 95% CI -0.39, -0.04), and crown-heel length (-0.44 cm, 95% CI -0.71, -0.18) in girls but not in boys in adjusted regression models. CONCLUSION In these pregnant women with moderate prenatal Cd exposure there evidence of adverse associations with birth anthropometry variables in the whole group. However, there was evidence of associations with anthropometric variables in girls that were not evident in boys. Sex-specific effects require further investigation in large cohorts as a possible contributor to the lack of associations generally found in mixed-sex studies.
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Affiliation(s)
- Caroline M. Taylor
- Centre for Child and Adolescent HealthSchool of Social and Community MedicineUniversity of BristolBristolUK
| | - Jean Golding
- Centre for Child and Adolescent HealthSchool of Social and Community MedicineUniversity of BristolBristolUK
| | - Alan M. Emond
- Centre for Child and Adolescent HealthSchool of Social and Community MedicineUniversity of BristolBristolUK
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20
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Mostafa GA, Bjørklund G, Urbina MA, Al-Ayadhi LY. The positive association between elevated blood lead levels and brain-specific autoantibodies in autistic children from low lead-polluted areas. Metab Brain Dis 2016; 31:1047-54. [PMID: 27250967 DOI: 10.1007/s11011-016-9836-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 05/16/2016] [Indexed: 12/31/2022]
Abstract
The underlying pathogenic mechanism in autoimmune disorders is the formation of autoantibodies. In children with autism spectrum disorder (ASD), it has been documented increased levels of brain-specific autoantibodies. Furthermore, lead (Pb) has been identified as one of the main neurotoxicants acting as environmental triggers for ASD as it induces neuroinflammation and autoimmunity. The present study is the first to explore a potential relationship between the levels of blood lead (BPb) and seropositivity of anti-ribosomal P protein antibodies in ASD children. Levels of BPb and serum anti-ribosomal P protein antibodies were measured in 60 children with ASD and 60 healthy control matched children, aged between 5 and 12 years, recruited from low Pb-polluted areas. The levels of BPb were significantly higher in ASD children than in healthy control children (P < 0.001). Patients with ASD had significantly higher frequency of increased BPb levels ≥10 μg/dL (43.3 %) than healthy control children (13.3 %; P < 0.001). There were significant and positive correlations between the levels of BPb, and the values of Childhood Autism Rating Scale (CARS) (P < 0.01) and IQ in children with ASD (P < 0.001). Patients with ASD showing increased levels of BPb had significantly higher frequency of seropositivity of anti-ribosomal P antibodies (92.3 %) than patients with normal BPb levels (32.3 %; P < 0.001). The findings of the present study suggest that increased levels of BPb in some children with ASD may trigger the production of serum anti-ribosomal P antibodies. Further research is warranted to determine if the production of brain autoantibodies is triggered by environmental Pb exposure in children with ASD. The possible therapeutic role of Pb chelators in ASD children should also be studied.
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Affiliation(s)
- Gehan Ahmed Mostafa
- Department of Pediatrics, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
- Department of Physiology, Autism Research and Treatment Center, AL-Amodi Autism Research Chair, Faculty of Medicine, King Saud University, Riyadh, Saudi Arabia.
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Mo i Rana, Norway
| | - Mauricio A Urbina
- Departamento de Zoología, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - Laila Yousef Al-Ayadhi
- Department of Physiology, Autism Research and Treatment Center, AL-Amodi Autism Research Chair, Faculty of Medicine, King Saud University, Riyadh, Saudi Arabia
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Dickerson AS, Rahbar MH, Bakian AV, Bilder DA, Harrington RA, Pettygrove S, Kirby RS, Durkin MS, Han I, Moyé LA, Pearson DA, Wingate MS, Zahorodny WM. Autism spectrum disorder prevalence and associations with air concentrations of lead, mercury, and arsenic. ENVIRONMENTAL MONITORING AND ASSESSMENT 2016; 188:407. [PMID: 27301968 DOI: 10.1007/s10661-016-5405-1] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 06/02/2016] [Indexed: 06/06/2023]
Abstract
Lead, mercury, and arsenic are neurotoxicants with known effects on neurodevelopment. Autism spectrum disorder (ASD) is a neurodevelopmental disorder apparent by early childhood. Using data on 4486 children with ASD residing in 2489 census tracts in five sites of the Centers for Disease Control and Prevention's Autism and Developmental Disabilities Monitoring (ADDM) Network, we used multi-level negative binomial models to investigate if ambient lead, mercury, and arsenic concentrations, as measured by the US Environmental Protection Agency National-Scale Air Toxics Assessment (EPA-NATA), were associated with ASD prevalence. In unadjusted analyses, ambient metal concentrations were negatively associated with ASD prevalence. After adjusting for confounding factors, tracts with air concentrations of lead in the highest quartile had significantly higher ASD prevalence than tracts with lead concentrations in the lowest quartile (prevalence ratio (PR) = 1.36; 95 '% CI: 1.18, 1.57). In addition, tracts with mercury concentrations above the 75th percentile (>1.7 ng/m(3)) and arsenic concentrations below the 75th percentile (≤0.13 ng/m(3)) had a significantly higher ASD prevalence (adjusted RR = 1.20; 95 % CI: 1.03, 1.40) compared to tracts with arsenic, lead, and mercury concentrations below the 75th percentile. Our results suggest a possible association between ambient lead concentrations and ASD prevalence and demonstrate that exposure to multiple metals may have synergistic effects on ASD prevalence.
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Affiliation(s)
- Aisha S Dickerson
- Biostatistics/Epidemiology/Research Design (BERD) Core, Center for Clinical and Translational Sciences (CCTS), University of Texas Health Science Center at Houston, 6410 Fannin Street, UT Professional Building Suite 1100.05, Houston, TX, 77030, USA.
| | - Mohammad H Rahbar
- Biostatistics/Epidemiology/Research Design (BERD) Core, Center for Clinical and Translational Sciences (CCTS), University of Texas Health Science Center at Houston, 6410 Fannin Street, UT Professional Building Suite 1100.05, Houston, TX, 77030, USA
- Division of Clinical and Translational Sciences, Department of Internal Medicine, McGovern Medical School The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
- Division of Epidemiology, Human Genetics, and Environmental Sciences (EHGES), University of Texas School of Public Health at Houston, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Amanda V Bakian
- Division of Child Psychiatry, Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, 84108, USA
| | - Deborah A Bilder
- Division of Child Psychiatry, Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, UT, 84108, USA
| | - Rebecca A Harrington
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Sydney Pettygrove
- Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ, 85721, USA
| | - Russell S Kirby
- Department of Community and Family Health, College of Public Health, University of South Florida, Tampa, FL, 33612, USA
| | - Maureen S Durkin
- Waisman Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53726, USA
| | - Inkyu Han
- Division of Epidemiology, Human Genetics, and Environmental Sciences (EHGES), University of Texas School of Public Health at Houston, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Lemuel A Moyé
- Division of Biostatistics, University of Texas School of Public Health at Houston, Houston, TX, 77030, USA
| | - Deborah A Pearson
- Department of Psychiatry and Behavioral Sciences, University of Texas Medical School, Houston, TX, 77054, USA
| | - Martha Slay Wingate
- Department of Health Care Organization and Policy, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, 35205, USA
| | - Walter M Zahorodny
- Department of Pediatrics, Rutgers New Jersey Medical School, Newark, NJ, 07103, USA
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22
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Keil KP, Lein PJ. DNA methylation: a mechanism linking environmental chemical exposures to risk of autism spectrum disorders? ENVIRONMENTAL EPIGENETICS 2016; 2:dvv012. [PMID: 27158529 PMCID: PMC4856164 DOI: 10.1093/eep/dvv012] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
There is now compelling evidence that gene by environment interactions are important in the etiology of autism spectrum disorders (ASDs). However, the mechanisms by which environmental factors interact with genetic susceptibilities to confer individual risk for ASD remain a significant knowledge gap in the field. The epigenome, and in particular DNA methylation, is a critical gene expression regulatory mechanism in normal and pathogenic brain development. DNA methylation can be influenced by environmental factors such as diet, hormones, stress, drugs, or exposure to environmental chemicals, suggesting that environmental factors may contribute to adverse neurodevelopmental outcomes of relevance to ASD via effects on DNA methylation in the developing brain. In this review, we describe epidemiological and experimental evidence implicating altered DNA methylation as a potential mechanism by which environmental chemicals confer risk for ASD, using polychlorinated biphenyls (PCBs), lead, and bisphenol A (BPA) as examples. Understanding how environmental chemical exposures influence DNA methylation and how these epigenetic changes modulate the risk and/or severity of ASD will not only provide mechanistic insight regarding gene-environment interactions of relevance to ASD but may also suggest potential intervention strategies for these and potentially other neurodevelopmental disorders.
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Affiliation(s)
- Kimberly P. Keil
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Pamela J. Lein
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
- *Correspondence address. Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, 1089 Veterinary Medicine Drive, Davis, CA 95616, USA. Tel:
(530) 752-1970
; Fax:
(530) 752-7690
; E-mail:
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Kim KN, Kwon HJ, Hong YC. Low-level lead exposure and autistic behaviors in school-age children. Neurotoxicology 2016; 53:193-200. [PMID: 26877220 DOI: 10.1016/j.neuro.2016.02.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 01/07/2016] [Accepted: 02/08/2016] [Indexed: 01/30/2023]
Abstract
INTRODUCTION The association between lead exposure and autism spectrum disorder is inconclusive. We hypothesized an association between higher blood lead concentrations and more autistic behaviors, including impaired social interactions and communication, stereotypical behaviors, and restricted interests, among school-age children. METHODS Data from 2473 Korean children aged 7-8years who had no prior history of developmental disorders were analyzed. Two follow-up surveys were conducted biennially until the children reached 11-12years of age. Blood lead concentrations were measured at every survey, and autistic behaviors were evaluated at 11-12years of age using the Autism Spectrum Screening Questionnaire (ASSQ) and Social Responsiveness Scale (SRS). The associations of blood lead concentration with ASSQ and SRS scores were analyzed using negative binomial, logistic, and linear regression models. RESULTS Blood lead concentrations at 7-8years of age (geometric mean: 1.64μg/dL), but not at 9-10 and 11-12years of age, were associated with more autistic behaviors at 11-12years of age, according to the ASSQ (β=0.151; 95% confidence interval [CI]: 0.061, 0.242) and SRS (β=2.489; 95% CI: 1.378, 3.600). SRS subscale analysis also revealed associations between blood lead concentrations and social awareness, cognition, communication, motivation, and mannerisms. CONCLUSION Even low blood lead concentrations at 7-8years of age are associated with more autistic behaviors at 11-12years of age, underscoring the need for continued efforts to reduce lead exposure.
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Affiliation(s)
- Kyoung-Nam Kim
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ho-Jang Kwon
- Department of Preventive Medicine and Public Health, Dankook University College of Medicine, Cheonan, Republic of Korea
| | - Yun-Chul Hong
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea; Institute of Environmental Medicine, Medical Research Center, Seoul, Republic of Korea; Environmental Health Center, Seoul National University College of Medicine, Seoul, Republic of Korea.
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24
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Does maternal VDR FokI single nucleotide polymorphism have an effect on lead levels of placenta, maternal and cord bloods? Placenta 2015; 36:870-5. [DOI: 10.1016/j.placenta.2015.06.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 06/23/2015] [Accepted: 06/25/2015] [Indexed: 11/20/2022]
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25
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Espín-Pérez A, de Kok TM, Jennen DG, Hendrickx DM, De Coster S, Schoeters G, Baeyens W, van Larebeke N, Kleinjans JC. Distinct genotype-dependent differences in transcriptome responses in humans exposed to environmental carcinogens. Carcinogenesis 2015; 36:1154-61. [DOI: 10.1093/carcin/bgv111] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 07/28/2015] [Indexed: 12/14/2022] Open
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26
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Lead excretion in spanish children with autism spectrum disorder. Brain Sci 2015; 5:58-68. [PMID: 25692508 PMCID: PMC4390791 DOI: 10.3390/brainsci5010058] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/24/2014] [Accepted: 02/05/2015] [Indexed: 11/17/2022] Open
Abstract
Among epigenetic factors leading to increased prevalence of juvenile neuropsychiatric disorders, including autism spectrum disorder, exposure to metals, such as lead (Pb) have led to conflicting results. The aim of the present study was to determine the levels of Pb in the urine of children with autism spectrum disorder (ASD) compared with typically developing children (TD) age- and sex-matched, and to analyze any association between core symptoms of ASD, special diets, supplements intake or prescription drugs and the concentration of Pb. The study was performed in a group of children with ASD (n = 35, average age 7.4 ± 0.5 years) and TD (n = 34, average age 7.7 ± 0.9 years). Measurement of lead in urine was performed by atomic absorption spectrometry; symptoms of ASD were analyzed by diagnostic and statistical manual of mental disorders (DMS-IV) using the questionnary ADI-R. Careful clinical evaluation was also undertaken and statistical analysis was done taking into account any possible confounding factor.
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Rahbar MH, Samms-Vaughan M, Dickerson AS, Loveland KA, Ardjomand-Hessabi M, Bressler J, Shakespeare-Pellington S, Grove ML, Boerwinkle E. Factors associated with blood lead concentrations of children in Jamaica. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2015; 50:529-39. [PMID: 25837555 PMCID: PMC4659644 DOI: 10.1080/10934529.2015.994932] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Lead is a heavy metal known to be detrimental to neurologic, physiologic, and behavioral health of children. Previous studies from Jamaica reported that mean lead levels in soil are four times that of lead levels in some other parts of the world. Other studies detected lead levels in fruits and root vegetables, which were grown in areas with lead contaminated soil. In this study, we investigate environmental factors associated with blood lead concentrations in Jamaican children. The participants in this study comprised 125 typically developing (TD) children (ages 2-8 years) who served as controls in an age- and sex-matched case-control study that enrolled children from 2009-2012 in Jamaica. We administered a questionnaire to assess demographic and socioeconomic information as well as potential exposures to lead through food. Using General Linear Models (GLMs), we identified factors associated with blood lead concentrations in Jamaican children. The geometric mean blood lead concentration (GMBLC) in the sample of children in this study was 2.80 μg dL(-1). In univariable GLM analyses, GMBLC was higher for children whose parents did not have education beyond high school compared to those whose parents had attained this level (3.00 μg dL(-1) vs. 2.31 μg dL(-1); P = 0.05), children living near a high traffic road compared to those who did not (3.43 μg dL(-1) vs. 2.52 μg dL(-1); P < 0.01), and children who reported eating ackee compared to those who did not eat this fruit (2.89 μg dL(-1) vs. 1.65 μg dL(-1); P < 0.05). In multivariable analysis, living near a high traffic road was identified as an independent risk factor for higher adjusted GMBLC (3.05 μg dL(-1) vs. 2.19 μg dL(-1); P = 0.01). While our findings indicate that GMBLC in Jamaican children has dropped by at least 62% during the past two decades, children living in Jamaica still have GMBLC that is twice that of children in more developed countries. In addition, we have identified significant risk factors for higher blood lead concentrations in Jamaican children. We believe increasing awareness among parents regarding these risk factors could potentially lead to a lower level of lead exposure in Jamaican children.
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Affiliation(s)
- Mohammad H Rahbar
- a Division of Epidemiology, Human Genetics, and Environmental Sciences , University of Texas School of Public Health at Houston , Houston , Texas , USA
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Rahbar MH, Samms-Vaughan M, Dickerson AS, Loveland KA, Ardjomand-Hessabi M, Bressler J, Shakespeare-Pellington S, Grove ML, Pearson DA, Boerwinkle E. Blood lead concentrations in Jamaican children with and without autism spectrum disorder. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2014; 12:83-105. [PMID: 25546274 PMCID: PMC4306851 DOI: 10.3390/ijerph120100083] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 12/15/2014] [Indexed: 12/15/2022]
Abstract
Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder manifesting by early childhood. Lead is a toxic metal shown to cause neurodevelopmental disorders in children. Several studies have investigated the possible association between exposure to lead and ASD, but their findings are conflicting. Using data from 100 ASD cases (2–8 years of age) and their age- and sex-matched typically developing controls, we investigated the association between blood lead concentrations (BLC) and ASD in Jamaican children. We administered a questionnaire to assess demographic and socioeconomic information as well as exposure to potential lead sources. We used General Linear Models (GLM) to assess the association of BLC with ASD status as well as with sources of exposure to lead. In univariable GLM, we found a significant difference between geometric mean blood lead concentrations of ASD cases and controls (2.25 μg/dL cases vs. 2.73 μg/dL controls, p < 0.05). However, after controlling for potential confounders, there were no significant differences between adjusted geometric mean blood lead concentrations of ASD cases and controls (2.55 μg/dL vs. 2.72 μg/dL, p = 0.64). Our results do not support an association between BLC and ASD in Jamaican children. We have identified significant confounders when assessing an association between ASD and BLC.
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Affiliation(s)
- Mohammad H Rahbar
- Division of Epidemiology, Human Genetics, and Environmental Sciences (EHGES), University of Texas School of Public Health at Houston, Houston, TX 77030, USA.
| | - Maureen Samms-Vaughan
- Department of Child & Adolescent Health, The University of the West Indies (UWI), Mona Campus, Kingston 7, Jamaica.
| | - Aisha S Dickerson
- Biostatistics/Epidemiology/Research Design (BERD) Component, Center for Clinical and Translational Sciences (CCTS), University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
| | - Katherine A Loveland
- Department of Psychiatry and Behavioral Sciences, University of Texas Medical School at Houston, Houston, TX 77054, USA.
| | - Manouchehr Ardjomand-Hessabi
- Biostatistics/Epidemiology/Research Design (BERD) Component, Center for Clinical and Translational Sciences (CCTS), University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
| | - Jan Bressler
- Human Genetics Center, University of Texas School of Public Health at Houston, Houston, TX 77030, USA.
| | | | - Megan L Grove
- Human Genetics Center, University of Texas School of Public Health at Houston, Houston, TX 77030, USA.
| | - Deborah A Pearson
- Department of Psychiatry and Behavioral Sciences, University of Texas Medical School at Houston, Houston, TX 77054, USA.
| | - Eric Boerwinkle
- Division of Epidemiology, Human Genetics, and Environmental Sciences (EHGES), University of Texas School of Public Health at Houston, Houston, TX 77030, USA.
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Smeester L, Yosim AE, Nye MD, Hoyo C, Murphy SK, Fry RC. Imprinted genes and the environment: links to the toxic metals arsenic, cadmium, lead and mercury. Genes (Basel) 2014; 5:477-96. [PMID: 24921406 PMCID: PMC4094944 DOI: 10.3390/genes5020477] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/24/2014] [Accepted: 05/27/2014] [Indexed: 12/17/2022] Open
Abstract
Imprinted genes defy rules of Mendelian genetics with their expression tied to the parent from whom each allele was inherited. They are known to play a role in various diseases/disorders including fetal growth disruption, lower birth weight, obesity, and cancer. There is increasing interest in understanding their influence on environmentally-induced disease. The environment can be thought of broadly as including chemicals present in air, water and soil, as well as food. According to the Agency for Toxic Substances and Disease Registry (ATSDR), some of the highest ranking environmental chemicals of concern include metals/metalloids such as arsenic, cadmium, lead and mercury. The complex relationships between toxic metal exposure, imprinted gene regulation/expression and health outcomes are understudied. Herein we examine trends in imprinted gene biology, including an assessment of the imprinted genes and their known functional roles in the cell, particularly as they relate to toxic metals exposure and disease. The data highlight that many of the imprinted genes have known associations to developmental diseases and are enriched for their role in the TP53 and AhR pathways. Assessment of the promoter regions of the imprinted genes resulted in the identification of an enrichment of binding sites for two transcription factor families, namely the zinc finger family II and PLAG transcription factors. Taken together these data contribute insight into the complex relationships between toxic metals in the environment and imprinted gene biology.
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Affiliation(s)
- Lisa Smeester
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina, 135 Dauer Drive, CB 7431, UNC, Chapel Hill, NC 27599, USA.
| | - Andrew E Yosim
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina, 135 Dauer Drive, CB 7431, UNC, Chapel Hill, NC 27599, USA.
| | - Monica D Nye
- Lineberger Comprehensive Cancer Center, The University of North Carolina, 450 West Street, CB 7295, UNC, Chapel Hill, NC 27599, USA.
| | - Cathrine Hoyo
- Department of Biological Sciences, Center for Human Health and Environment, Campus Box 7633, NC State University, Raleigh, NC 27695, USA.
| | - Susan K Murphy
- Department of Obstetrics and Gynecology, Duke University Medical Center, B226 LSRC, Box 91012, Research Drive, Durham, NC 27708, USA.
| | - Rebecca C Fry
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina, 135 Dauer Drive, CB 7431, UNC, Chapel Hill, NC 27599, USA.
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30
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Goyal DK, Miyan JA. Neuro-immune abnormalities in autism and their relationship with the environment: a variable insult model for autism. Front Endocrinol (Lausanne) 2014; 5:29. [PMID: 24639668 PMCID: PMC3945747 DOI: 10.3389/fendo.2014.00029] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 02/20/2014] [Indexed: 12/20/2022] Open
Abstract
Autism spectrum disorder (ASD) is a heterogeneous condition affecting an individual's ability to communicate and socialize and often presents with repetitive movements or behaviors. It tends to be severe with less than 10% achieving independent living with a marked variation in the progression of the condition. To date, the literature supports a multifactorial model with the largest, most detailed twin study demonstrating strong environmental contribution to the development of the condition. Here, we present a brief review of the neurological, immunological, and autonomic abnormalities in ASD focusing on the causative roles of environmental agents and abnormal gut microbiota. We present a working hypothesis attempting to bring together the influence of environment on the abnormal neurological, immunological, and neuroimmunological functions and we explain in brief how such pathophysiology can lead to, and/or exacerbate ASD symptomatology. At present, there is a lack of consistent findings relating to the neurobiology of autism. Whilst we postulate such variable findings may reflect the marked heterogeneity in clinical presentation and as such the variable findings may be of pathophysiological relevance, more research into the neurobiology of autism is necessary before establishing a working hypothesis. Both the literature review and hypothesis presented here explore possible neurobiological explanations with an emphasis of environmental etiologies and are presented with this bias.
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Affiliation(s)
- Daniel K. Goyal
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
| | - Jaleel A. Miyan
- Faculty of Life Sciences, The University of Manchester, Manchester, UK
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31
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Anderson G, Maes M. Redox Regulation and the Autistic Spectrum: Role of Tryptophan Catabolites, Immuno-inflammation, Autoimmunity and the Amygdala. Curr Neuropharmacol 2014; 12:148-67. [PMID: 24669209 PMCID: PMC3964746 DOI: 10.2174/1570159x11666131120223757] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 08/18/2013] [Accepted: 11/02/2013] [Indexed: 12/12/2022] Open
Abstract
The autistic spectrum disorders (ASD) form a set of multi-faceted disorders with significant genetic, epigenetic and environmental determinants. Oxidative and nitrosative stress (O&NS), immuno-inflammatory pathways, mitochondrial dysfunction and dysregulation of the tryptophan catabolite (TRYCATs) pathway play significant interactive roles in driving the early developmental etiology and course of ASD. O&NS interactions with immuno-inflammatory pathways mediate their effects centrally via the regulation of astrocyte and microglia responses, including regional variations in TRYCATs produced. Here we review the nature of these interactions and propose an early developmental model whereby different ASD genetic susceptibilities interact with environmental and epigenetic processes, resulting in glia biasing the patterning of central interarea interactions. A role for decreased local melatonin and N-acetylserotonin production by immune and glia cells may be a significant treatment target.
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Affiliation(s)
| | - Michael Maes
- Department of Psychiatry, Chulalongkorn University, Bangkok, Thailand
- Department of Psychiatry, Deakin University, Geelong, Australia
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32
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Rossignol DA, Genuis SJ, Frye RE. Environmental toxicants and autism spectrum disorders: a systematic review. Transl Psychiatry 2014; 4:e360. [PMID: 24518398 PMCID: PMC3944636 DOI: 10.1038/tp.2014.4] [Citation(s) in RCA: 292] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 12/15/2013] [Accepted: 01/06/2014] [Indexed: 11/21/2022] Open
Abstract
Although the involvement of genetic abnormalities in autism spectrum disorders (ASD) is well-accepted, recent studies point to an equal contribution by environmental factors, particularly environmental toxicants. However, these toxicant-related studies in ASD have not been systematically reviewed to date. Therefore, we compiled publications investigating potential associations between environmental toxicants and ASD and arranged these publications into the following three categories: (a) studies examining estimated toxicant exposures in the environment during the preconceptional, gestational and early childhood periods; (b) studies investigating biomarkers of toxicants; and (c) studies examining potential genetic susceptibilities to toxicants. A literature search of nine electronic scientific databases through November 2013 was performed. In the first category examining ASD risk and estimated toxicant exposures in the environment, the majority of studies (34/37; 92%) reported an association. Most of these studies were retrospective case-control, ecological or prospective cohort studies, although a few had weaker study designs (for example, case reports or series). Toxicants implicated in ASD included pesticides, phthalates, polychlorinated biphenyls (PCBs), solvents, toxic waste sites, air pollutants and heavy metals, with the strongest evidence found for air pollutants and pesticides. Gestational exposure to methylmercury (through fish exposure, one study) and childhood exposure to pollutants in water supplies (two studies) were not found to be associated with ASD risk. In the second category of studies investigating biomarkers of toxicants and ASD, a large number was dedicated to examining heavy metals. Such studies demonstrated mixed findings, with only 19 of 40 (47%) case-control studies reporting higher concentrations of heavy metals in blood, urine, hair, brain or teeth of children with ASD compared with controls. Other biomarker studies reported that solvent, phthalate and pesticide levels were associated with ASD, whereas PCB studies were mixed. Seven studies reported a relationship between autism severity and heavy metal biomarkers, suggesting evidence of a dose-effect relationship. Overall, the evidence linking biomarkers of toxicants with ASD (the second category) was weaker compared with the evidence associating estimated exposures to toxicants in the environment and ASD risk (the first category) because many of the biomarker studies contained small sample sizes and the relationships between biomarkers and ASD were inconsistent across studies. Regarding the third category of studies investigating potential genetic susceptibilities to toxicants, 10 unique studies examined polymorphisms in genes associated with increased susceptibilities to toxicants, with 8 studies reporting that such polymorphisms were more common in ASD individuals (or their mothers, 1 study) compared with controls (one study examined multiple polymorphisms). Genes implicated in these studies included paraoxonase (PON1, three of five studies), glutathione S-transferase (GSTM1 and GSTP1, three of four studies), δ-aminolevulinic acid dehydratase (one study), SLC11A3 (one study) and the metal regulatory transcription factor 1 (one of two studies). Notably, many of the reviewed studies had significant limitations, including lack of replication, limited sample sizes, retrospective design, recall and publication biases, inadequate matching of cases and controls, and the use of nonstandard tools to diagnose ASD. The findings of this review suggest that the etiology of ASD may involve, at least in a subset of children, complex interactions between genetic factors and certain environmental toxicants that may act synergistically or in parallel during critical periods of neurodevelopment, in a manner that increases the likelihood of developing ASD. Because of the limitations of many of the reviewed studies, additional high-quality epidemiological studies concerning environmental toxicants and ASD are warranted to confirm and clarify many of these findings.
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Affiliation(s)
- D A Rossignol
- Family Medicine, Rossignol Medical Center, Irvine, CA, USA
| | - S J Genuis
- Faculty of Medicine, University of Alberta, Edmonton, AB, Canada
| | - R E Frye
- Arkansas Children's Hospital Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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33
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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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34
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De Coster S, van Leeuwen DM, Jennen DGJ, Koppen G, Den Hond E, Nelen V, Schoeters G, Baeyens W, van Delft JHM, Kleinjans JCS, van Larebeke N. Gender-specific transcriptomic response to environmental exposure in Flemish adults. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2013; 54:574-588. [PMID: 23653218 DOI: 10.1002/em.21774] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 02/01/2013] [Accepted: 02/21/2013] [Indexed: 06/02/2023]
Abstract
Flanders, Belgium, is one of the most densely populated areas in Europe. The Flemish Environment and Health Survey (2002-2006) aimed at determining exposure to pollutants of neonates, adolescents, and older adults and to assess associated biological and health effects. This study investigated genome wide gene expression changes associated with a range of environmental pollutants, including cadmium, lead, PCBs, dioxin, hexachlorobenzene, p,p'-DDE, benzene, and PAHs. Gene expression levels were measured in peripheral blood cells of 20 adults with relatively high and 20 adults with relatively low combined internal exposure levels, all non-smokers aged 50-65. Pearson correlation was used to analyze associations between pollutants and gene expression levels, separately for both genders. Pollutant- and gender-specific correlation analysis results were obtained. For organochlorine pollutants, analysis within genders revealed that genes were predominantly regulated in opposite directions in males and females. Significantly modulated pathways were found to be associated with each of the exposure biomarkers measured. Pathways and/or genes related to estrogen and STAT5 signaling were correlated to organochlorine exposures in both genders. Our work demonstrates that gene expression in peripheral blood is influenced by environmental pollutants. In particular, gender-specific changes are associated with organochlorine pollutants, including gender-specific modulation of endocrine related pathways and genes. These pathways and genes have previously been linked to endocrine disruption related disorders, which in turn have been associated with organochlorine exposure. Based on our results, we recommend that males and females be considered separately when analyzing gene expression changes associated with exposures that may include chemicals with endocrine disrupting properties.
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Affiliation(s)
- Sam De Coster
- Study Centre for Carcinogenesis and Primary Prevention of Cancer, Ghent University, Ghent, 9000, Belgium
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Goines PE, Ashwood P. Cytokine dysregulation in autism spectrum disorders (ASD): possible role of the environment. Neurotoxicol Teratol 2013; 36:67-81. [PMID: 22918031 PMCID: PMC3554862 DOI: 10.1016/j.ntt.2012.07.006] [Citation(s) in RCA: 190] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 07/03/2012] [Accepted: 07/31/2012] [Indexed: 02/07/2023]
Abstract
Autism spectrum disorders (ASD) are neurodevelopmental diseases that affect an alarming number of individuals. The etiological basis of ASD is unclear, and evidence suggests it involves both genetic and environmental factors. There are many reports of cytokine imbalances in ASD. These imbalances could have a pathogenic role, or they may be markers of underlying genetic and environmental influences. Cytokines act primarily as mediators of immunological activity but they also have significant interactions with the nervous system. They participate in normal neural development and function, and inappropriate activity can have a variety of neurological implications. It is therefore possible that cytokine dysregulation contributes directly to neural dysfunction in ASD. Further, cytokine profiles change dramatically in the face of infection, disease, and toxic exposures. Imbalances in cytokines may represent an immune response to environmental contributors to ASD. The following review is presented in two main parts. First, we discuss select cytokines implicated in ASD, including IL-1Β, IL-6, IL-4, IFN-γ, and TGF-Β, and focus on their role in the nervous system. Second, we explore several neurotoxic environmental factors that may be involved in the disorders, and focus on their immunological impacts. This review represents an emerging model that recognizes the importance of both genetic and environmental factors in ASD etiology. We propose that the immune system provides critical clues regarding the nature of the gene by environment interactions that underlie ASD pathophysiology.
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Affiliation(s)
- Paula E. Goines
- University of California, Davis, School of Veterinary Medicine, Department of Molecular Biosciences
| | - Paul Ashwood
- University of California, Davis, School of Medicine, Department of Medical Microbiology and Immunology
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Genuis SJ, Schwalfenberg G, Siy AKJ, Rodushkin I. Toxic element contamination of natural health products and pharmaceutical preparations. PLoS One 2012; 7:e49676. [PMID: 23185404 PMCID: PMC3504157 DOI: 10.1371/journal.pone.0049676] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 10/15/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Concern has recently emerged regarding the safety of natural health products (NHPs)-therapies that are increasingly recommended by various health providers, including conventional physicians. Recognizing that most individuals in the Western world now consume vitamins and many take herbal agents, this study endeavored to determine levels of toxic element contamination within a range of NHPs. METHODS Toxic element testing was performed on 121 NHPs (including Ayurvedic, traditional Chinese, and various marine-source products) as well as 49 routinely prescribed pharmaceutical preparations. Testing was also performed on several batches of one prenatal supplement, with multiple samples tested within each batch. Results were compared to existing toxicant regulatory limits. RESULTS Toxic element contamination was found in many supplements and pharmaceuticals; levels exceeding established limits were only found in a small percentage of the NHPs tested and none of the drugs tested. Some NHPs demonstrated contamination levels above preferred daily endpoints for mercury, cadmium, lead, arsenic or aluminum. NHPs manufactured in China generally had higher levels of mercury and aluminum. CONCLUSIONS Exposure to toxic elements is occurring regularly as a result of some contaminated NHPs. Best practices for quality control-developed and implemented by the NHP industry with government oversight-is recommended to guard the safety of unsuspecting consumers.
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Affiliation(s)
- Stephen J Genuis
- Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada.
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Disruption of social approach by MK-801, amphetamine, and fluoxetine in adolescent C57BL/6J mice. Neurotoxicol Teratol 2012; 36:36-46. [PMID: 22898204 DOI: 10.1016/j.ntt.2012.07.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 07/28/2012] [Accepted: 07/30/2012] [Indexed: 11/23/2022]
Abstract
Autism is a severe neurodevelopmental disorder, diagnosed on the basis of core behavioral symptoms. Although the mechanistic basis for the disorder is not yet known, genetic analyses have suggested a role for abnormal excitatory/inhibitory signaling systems in brain, including dysregulation of glutamatergic neurotransmission. In mice, the constitutive knockdown of NMDA receptors leads to social deficits, repetitive behavior, and self-injurious responses that reflect aspects of the autism clinical profile. However, social phenotypes differ with age: mice with reduced NMDA-receptor function exhibit hypersociability in adolescence, but markedly deficient sociability in adulthood. The present studies determined whether acute disruption of NMDA neurotransmission leads to exaggerated social approach, similar to that observed with constitutive disruption, in adolescent C57BL/6J mice. The effects of MK-801, an NMDA receptor antagonist, were compared with amphetamine, a dopamine agonist, and fluoxetine, a selective serotonin reuptake inhibitor, on performance in a three-chamber choice task. Results showed that acute treatment with MK-801 led to social approach deficits at doses without effects on entry numbers. Amphetamine also decreased social preference, but increased number of entries at every dose. Fluoxetine (10 mg/kg) had selective effects on social novelty preference. Withdrawal from a chronic ethanol regimen decreased activity, but did not attenuate sociability. Low doses of MK-801 and amphetamine were also evaluated in a marble-burying assay for repetitive behavior. MK-801, at a dose that did not disrupt sociability or alter entries, led to a profound reduction in marble-burying. Overall, these findings demonstrate that moderate alteration of NMDA, dopamine, or serotonin function can attenuate social preference in wild type mice.
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Gillis BS, Arbieva Z, Gavin IM. Analysis of lead toxicity in human cells. BMC Genomics 2012; 13:344. [PMID: 22839698 PMCID: PMC3424832 DOI: 10.1186/1471-2164-13-344] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 07/27/2012] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Lead is a metal with many recognized adverse health side effects, and yet the molecular processes underlying lead toxicity are still poorly understood. Quantifying the injurious effects of lead is also difficult because of the diagnostic limitations that exist when analyzing human blood and urine specimens for lead toxicity. RESULTS We analyzed the deleterious impact of lead on human cells by measuring its effects on cytokine production and gene expression in peripheral blood mononuclear cells. Lead activates the secretion of the chemokine IL-8 and impacts mitogen-dependent activation by increasing the secretion of the proinflammatory cytokines IL-6 and TNF-α and of the chemokines IL-8 and MIP1-α in the presence of phytohemagglutinin. The recorded changes in gene expression affected major cellular functions, including metallothionein expression, and the expression of cellular metabolic enzymes and protein kinase activity. The expression of 31 genes remained elevated after the removal of lead from the testing medium thereby allowing for the measurement of adverse health effects of lead poisoning. These included thirteen metallothionein transcripts, three endothelial receptor B transcripts and a number of transcripts which encode cellular metabolic enzymes. Cellular responses to lead correlated with blood lead levels and were significantly altered in individuals with higher lead content resultantly affecting the nervous system, the negative regulation of transcription and the induction of apoptosis. In addition, we identified changes in gene expression in individuals with elevated zinc protoporphyrin blood levels and found that genes regulating the transmission of nerve impulses were affected in these individuals. The affected pathways were G-protein mediated signaling, gap junction signaling, synaptic long-term potentiation, neuropathic pain signaling as well as CREB signaling in neurons. Cellular responses to lead were altered in subjects with high zinc protoporphyrin blood levels. CONCLUSIONS The results of our study defined specific changes in gene and protein expression in response to lead challenges and determined the injurious effects of exposures to lead on a cellular level. This information can be used for documenting the health effects of exposures to lead which will facilitate identifying and monitoring efficacious treatments for lead-related maladies.
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Affiliation(s)
- Bruce S Gillis
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Zarema Arbieva
- Research Resources Center, University of Illinois at Chicago, Chicago, IL, USA
| | - Igor M Gavin
- Research Resources Center, University of Illinois at Chicago, Chicago, IL, USA
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Ghanizadeh A. Novel treatment for lead exposure in children with autism. Biol Trace Elem Res 2011; 142:257-8. [PMID: 20706805 DOI: 10.1007/s12011-010-8800-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 07/30/2010] [Indexed: 11/28/2022]
Affiliation(s)
- Ahmad Ghanizadeh
- Research Center for Psychiatry and Behavioral Sciences, Department of Psychiatry, Shiraz University of Medical Sciences, Hafez Hospital, Shiraz, Iran.
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Karsten SL, Kudo LC, Bragin AJ. Use of peripheral blood transcriptome biomarkers for epilepsy prediction. Neurosci Lett 2011; 497:213-7. [PMID: 21419828 DOI: 10.1016/j.neulet.2011.03.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 03/06/2011] [Accepted: 03/07/2011] [Indexed: 12/13/2022]
Abstract
There are currently no predictive methods to identify patients who suffered an initial brain injury and are at high risk of developing chronic epilepsy. Consequently, treatments aimed at epilepsy prevention that would target the underlying epileptogenic process are neither available nor being developed. After a brain injury or any other initial precipitating event (IPE) to the development of epilepsy, pathological changes may occur in forms of inflammation, damage in the blood brain barrier, neuron loss, gliosis, axon sprouting, etc., in multiple brain areas. Recent studies provide connections between various kinds of brain pathology and alterations in the peripheral blood transcriptome. In this review we discuss the possibility of using peripheral blood transcriptome biomarkers for the detection of epileptogenesis and consequently, subjects at high risk of developing epilepsy.
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Affiliation(s)
- Stanislav L Karsten
- Division of Neuroscience, Department of Neurology, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA 90504, USA.
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Tian Y, Gunther JR, Liao IH, Liu D, Ander BP, Stamova BS, Lit L, Jickling GC, Xu H, Zhan X, Sharp FR. GABA- and acetylcholine-related gene expression in blood correlate with tic severity and microarray evidence for alternative splicing in Tourette syndrome: a pilot study. Brain Res 2011; 1381:228-36. [PMID: 21241679 DOI: 10.1016/j.brainres.2011.01.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 12/08/2010] [Accepted: 01/10/2011] [Indexed: 10/18/2022]
Abstract
Tourette syndrome (TS) is a complex childhood neurodevelopmental disorder characterized by motor and vocal tics. Recently, altered numbers of GABAergic-parvalbumin (PV) and cholinergic interneurons were observed in the basal ganglia of individuals with TS. Thus, we postulated that gamma-amino butyric acid (GABA)- and acetylcholine (ACh)-related genes might be associated with the pathophysiology of TS. Total RNA isolated from whole blood of 26 un-medicated TS subjects and 23 healthy controls (HC) was processed on Affymetrix Human Exon 1.0 ST arrays. Data were analyzed to identify genes whose expression correlated with tic severity in TS, and to identify genes differentially spliced in TS compared to HC subjects. Many genes (3627) correlated with tic severity in TS (p < 0.05) among which GABA- (p = 2.1 × 10⁻³) and ACh- (p = 4.25 × 10⁻⁸) related genes were significantly over-represented. Moreover, several GABA and ACh-related genes were predicted to be alternatively spliced in TS compared to HC including GABA receptors GABRA4 and GABRG1, the nicotinic ACh receptor CHRNA4 and cholinergic differentiation factor (CDF). This pilot study suggests that at least some of these GABA- and ACh-related genes observed in blood that correlate with tics or are alternatively spliced are involved in the pathophysiology of TS and tics.
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Affiliation(s)
- Yingfang Tian
- University of California at Davis, M.I.N.D., Institute and Department of Neurology, USA
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Tian Y, Liao IH, Zhan X, Gunther JR, Ander BP, Liu D, Lit L, Jickling GC, Corbett BA, Bos-Veneman NGP, Hoekstra PJ, Sharp FR. Exon expression and alternatively spliced genes in Tourette Syndrome. Am J Med Genet B Neuropsychiatr Genet 2011; 156B:72-8. [PMID: 21184586 PMCID: PMC3070201 DOI: 10.1002/ajmg.b.31140] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Accepted: 10/07/2010] [Indexed: 11/08/2022]
Abstract
Tourette Syndrome (TS) is diagnosed based upon clinical criteria including motor and vocal tics. We hypothesized that differences in exon expression and splicing might be useful for pathophysiology and diagnosis. To demonstrate exon expression and alternatively spliced gene differences in blood of individuals with TS compared to healthy controls (HC), RNA was isolated from the blood of 26 un-medicated TS subjects and 23 HC. Each sample was run on Affymetrix Human Exon 1.0 ST (HuExon) arrays and on 3' biased U133 Plus 2.0 (HuU133) arrays. To investigate the differentially expressed exons and transcripts, analyses of covariance (ANCOVA) were performed, controlling for age, gender, and batch. Differential alternative splicing patterns between TS and HC were identified using analyses of variance (ANOVA) models in Partek. Three hundred and seventy-six exon probe sets were differentially expressed between TS and HC (raw P < 0.005, fold change >|1.2|) that separated TS and HC subjects using hierarchical clustering and Principal Components Analysis. The probe sets predicted TS compared to HC with a >90% sensitivity and specificity using a 10-fold cross-validation. Ninety genes (transcripts) had differential expression of a single exon (raw P < 0.005) and were predicted to be alternatively spliced (raw P < 0.05) in TS compared to HC. These preliminary findings might provide insight into the pathophysiology of TS and potentially provide prognostic and diagnostic biomarkers. However, the findings are tempered by the small sample size and multiple comparisons and require confirmation using PCR or deep RNA sequencing and a much larger patient population.
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Affiliation(s)
- Yingfang Tian
- M.I.N.D. Institute, Department of Neurology, University of California at Davis, Sacramento, 95817, USA.
| | - Isaac H. Liao
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Xinhua Zhan
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Joan R. Gunther
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Bradley P. Ander
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Dazhi Liu
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Lisa Lit
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Glen C. Jickling
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
| | - Blythe A. Corbett
- M.I.N.D. Institute and Department of Psychiatry, University of California at Davis, Sacramento, California. USA
| | - Netty GP. Bos-Veneman
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Netherlands
| | - Pieter J. Hoekstra
- Department of Psychiatry, University Medical Center Groningen, University of Groningen, Netherlands
| | - Frank R. Sharp
- M.I.N.D. Institute and Department of Neurology, University of California at Davis, Sacramento, California. USA
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Correlations between gene expression and mercury levels in blood of boys with and without autism. Neurotox Res 2009; 19:31-48. [PMID: 19937285 PMCID: PMC3006666 DOI: 10.1007/s12640-009-9137-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 10/15/2009] [Accepted: 11/10/2009] [Indexed: 01/23/2023]
Abstract
Gene expression in blood was correlated with mercury levels in blood of 2- to 5-year-old boys with autism (AU) compared to age-matched typically developing (TD) control boys. This was done to address the possibility that the two groups might metabolize toxicants, such as mercury, differently. RNA was isolated from blood and gene expression assessed on whole genome Affymetrix Human U133 expression microarrays. Mercury levels were measured using an inductively coupled plasma mass spectrometer. Analysis of covariance (ANCOVA) was performed and partial correlations between gene expression and mercury levels were calculated, after correcting for age and batch effects. To reduce false positives, only genes shared by the ANCOVA models were analyzed. Of the 26 genes that correlated with mercury levels in both AU and TD boys, 11 were significantly different between the groups (P(Diagnosis*Mercury) ≤ 0.05). The expression of a large number of genes (n = 316) correlated with mercury levels in TD but not in AU boys (P ≤ 0.05), the most represented biological functions being cell death and cell morphology. Expression of 189 genes correlated with mercury levels in AU but not in TD boys (P ≤ 0.05), the most represented biological functions being cell morphology, amino acid metabolism, and antigen presentation. These data and those in our companion study on correlation of gene expression and lead levels show that AU and TD children display different correlations between transcript levels and low levels of mercury and lead. These findings might suggest different genetic transcriptional programs associated with mercury in AU compared to TD children.
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