Dioxins and related environmental contaminants increase TDP-43 levels

Autor: Yorghos Tripodis, Alejandra Ramirez-Cardenas, David H. Sherr, George J. Murphy, Heather I. Ballance, James M. Murithi, Peter E.A. Ash, Samantha Boudeau, Ali Al Abdulatif, Benjamin Wolozin, Elizabeth A. Stanford, Amanda Jeh
Jazyk: angličtina
Rok vydání: 2017
Předmět:
0301 basic medicine
Male
Polychlorinated Dibenzodioxins
lcsh:Geriatrics
lcsh:RC346-429
Mice
0302 clinical medicine
Toxicants
Polycyclic Aromatic Hydrocarbons
Induced pluripotent stem cell
Ataxin-2
Regulation of gene expression
Neurons
Gene knockdown
biology
Chemistry
Neurodegeneration
Brain
3. Good health
DNA-Binding Proteins
Biochemistry
Environmental Pollutants
Protein aggregation
Transcription
Research Article
TARDBP
Cell Line
Alpha-synuclein
03 medical and health sciences
Cellular and Molecular Neuroscience
medicine
Animals
Humans
Molecular Biology
Transcription factor
Carcinogen
lcsh:Neurology. Diseases of the nervous system
Fus
Amyotrophic Lateral Sclerosis
Promoter
medicine.disease
Aryl hydrocarbon receptor
Gene regulation
Mice
Inbred C57BL

lcsh:RC952-954.6
030104 developmental biology
Receptors
Aryl Hydrocarbon

biology.protein
Cancer research
Neurology (clinical)
ALS
030217 neurology & neurosurgery
Zdroj: Molecular Neurodegeneration, Vol 12, Iss 1, Pp 1-14 (2017)
Molecular Neurodegeneration
ISSN: 1750-1326
DOI: 10.1186/s13024-017-0177-9
Popis: Background Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative condition that is characterized by progressive loss of motor neurons and the accumulation of aggregated TAR DNA Binding Protein-43 (TDP-43, gene: TARDBP). Increasing evidence indicates that environmental factors contribute to the risk of ALS. Dioxins, related planar polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants that activate the aryl hydrocarbon receptor (AHR), a ligand-activated, PAS family transcription factor. Recently, exposure to these toxicants was identified as a risk factor for ALS. Methods We examined levels of TDP-43 reporter activity, transcript and protein. Quantification was done using cell lines, induced pluripotent stem cells (iPSCs) and mouse brain. The target samples were treated with AHR agonists, including 6-Formylindolo[3,2-b]carbazole (FICZ, a potential endogenous ligand, 2,3,7,8-tetrachlorodibenzo(p)dioxin, and benzo(a)pyrene, an abundant carcinogen in cigarette smoke). The action of the agonists was inhibited by concomitant addition of AHR antagonists or by AHR-specific shRNA. Results We now report that AHR agonists induce up to a 3-fold increase in TDP-43 protein in human neuronal cell lines (BE-M17 cells), motor neuron differentiated iPSCs, and in murine brain. Chronic treatment with AHR agonists elicits over 2-fold accumulation of soluble and insoluble TDP-43, primarily because of reduced TDP-43 catabolism. AHR antagonists or AHR knockdown inhibits agonist-induced increases in TDP-43 protein and TARDBP transcription demonstrating that the ligands act through the AHR. Conclusions These results provide the first evidence that environmental AHR ligands increase TDP-43, which is the principle pathological protein associated with ALS. These results suggest novel molecular mechanisms through which a variety of prevalent environmental factors might directly contribute to ALS. The widespread distribution of dioxins, PCBs and PAHs is considered to be a risk factor for cancer and autoimmune diseases, but could also be a significant public health concern for ALS. Electronic supplementary material The online version of this article (doi:10.1186/s13024-017-0177-9) contains supplementary material, which is available to authorized users.
Databáze: OpenAIRE