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Cited by 49Alzheimer's disease research and treatmentsHeavy Metal Exposure and ToxicityParkinson's Disease Mechanisms and Treatments

Heavy metals contaminating the environment of a progressive supranuclear palsy cluster induce tau accumulation and cell death in cultured neurons

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Alquezar, Carolina, Felix, Jessica B., McCandlish, Elizabeth, Buckley, Brian T., Caparros-Lefebvre, Dominique, Karch, Celeste M., Golbe, Lawrence I., Kao, Aimee W.·2020·Scientific Reports
DOI 10.1038/s41598-019-56930-wPMC PMC6969162
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Abstract

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by the presence of intracellular aggregates of tau protein and neuronal loss leading to cognitive and motor impairment. Occurrence is mostly sporadic, but rare family clusters have been described. Although the etiopathology of PSP is unknown, mutations in the MAPT/tau gene and exposure to environmental toxins can increase the risk of PSP. Here, we used cell models to investigate the potential neurotoxic effects of heavy metals enriched in a highly industrialized region in France with a cluster of sporadic PSP cases. We found that iPSC-derived iNeurons from a MAPT mutation carrier tend to be more sensitive to cell death induced by chromium (Cr) and nickel (Ni) exposure than an isogenic control line. We hypothesize that genetic variations may predispose to neurodegeneration induced by those heavy metals. Furthermore, using an SH-SY5Y neuroblastoma cell line, we showed that both heavy metals induce cell death by an apoptotic mechanism. Interestingly, Cr and Ni treatments increased total and phosphorylated tau levels in both cell types, implicating Cr and Ni exposure in tau pathology. Overall, this study suggests that chromium and nickel could contribute to the pathophysiology of tauopathies such as PSP by promoting tau accumulation and neuronal cell death.

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  • Possession of a single mutant allele responsible for certain childhood lysosomal disorders increases risk for a range of adult neurodegenerative disorders, including Alzheimer's disease, frontotemporal dementia and Parkinson's disease.

    “We now know that possession of a single mutant allele responsible for certain childhood disorders—those involving the lysosome—increases risk for a range of adult neurodegenerative disorders, including Alzheimer’s disease (AD), frontotemporal dementia (FTD) and Parkinson’s disease (PD).5,7”

    From The lysosome and proteostatic stress at the intersection of pediatric neurological disorders and adult neurodegenerative diseases (2025) · cites this paper as [7]

    The Introduction discusses genetic variants in progressive supranuclear palsy, and the Results describe neurons carrying a heterozygous MAPT mutation. Neither passage addresses whether carrying one allele for a childhood lysosomal disorder increases risk of Alzheimer’s disease, frontotemporal dementia or Parkinson’s disease. Searches for lysosomal disorders and single-allele carrier risk found no passage making that link. (LLM, conf=0.76)

    Experimental — accuracy not yet measured

  • Some PD risk genes, such as ASAH1 and GLB1, have only been identified in a single GWAS study of PD risk, with no mechanistic or confirmatory follow up.

    “In contrast to the genes above, which have stronger links both genetically and mechanistically to PD, some PD risk genes, such as ASAH1 and GLB1, have only been identified in a single GWAS study of PD risk, with no mechanistic or confirmatory follow up.7”

    From The lysosome and proteostatic stress at the intersection of pediatric neurological disorders and adult neurodegenerative diseases (2025) · cites this paper as [7]

    The Introduction discusses genetic associations with progressive supranuclear palsy and environmental exposure, not ASAH1 or GLB1 as Parkinson’s disease risk genes. Searches for those genes and for a single PD GWAS with no follow-up found no passage addressing the claim in our copy. The indexed passages have no page numbers. (LLM, conf=0.76)

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Authors
Alquezar, C., Felix, J. B., McCandlish, E., Buckley, B. T., Caparros-Lefebvre, D., Karch, C. M., Golbe, L. I., & Kao, A. W.
Affiliations
  • Baylor College of Medicine (US)
  • Rutgers, The State University of New Jersey (US)
  • Washington University in St. Louis (US)
  • University of California, San Francisco (US)
Corresponding author
Kao, Aimee W.
ORCID
Venue
Scientific Reports
Publisher
Springer Science and Business Media LLC
Published
2020-01-17
Volume
10
Issue
1
Pages
569-569
ISSN
2045-2322 (ISSN-L)
DOI
10.1038/s41598-019-56930-w
PMC
PMC6969162
OpenAlex
W3000485982
Cited by
49
References
3
Citations by year
2026: 6 · 2025: 7 · 2024: 4 · 2023: 8 · 2022: 9 · 2021: 7 · 2020: 8
FWCI
4.96
Type
journal article
Language
en
Open access
Licence
Locations
  • Scientific Reports (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Rutgers University Community Repository (Rutgers University) (submittedVersion)
  • Digital Commons@Becker (Washington University School of Medicine) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
  • eScholarship (California Digital Library) (submittedVersion)
  • eScholarship (California Digital Library) (submittedVersion, cc-by)
Funders
  • California Institute for Regenerative Medicine (TB1-01188)
  • Paul G. Allen Family Foundation
  • Fundación Ramón Areces
  • CurePSP
  • National Institutes of Health (AG05681)
  • National Institute on Aging (K01AG046374, R01AG059052, P50AG005681, P30AG066444)
  • National Institute of Environmental Health Sciences (P30ES05022, P30ES005022)
Topics
  • Health Sciences › Medicine › Physiology › Alzheimer's disease research and treatments
  • Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Heavy Metal Exposure and Toxicity
  • Health Sciences › Medicine › Neurology › Parkinson's Disease Mechanisms and Treatments
Keywords
progressive supranuclear palsy, heavy metal exposure, chromium, nickel, tau accumulation, tau phosphorylation, neuronal cell death, apoptosis, iPSC-derived neurons, MAPT mutations, tauopathy, neurotoxicity, environmental toxins, neurodegeneration, industrialized regions
MeSH terms
Cell Line, Cell Survival, Chromium, France, Humans, Models, Biological, Neurons, Nickel, Supranuclear Palsy, Progressive, tau Proteins, Cell Death, Metals, Heavy, Induced Pluripotent Stem Cells, Neural Stem Cells

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