title: Transcriptional and metabolic adaptation of human neurons to the mitochondrial toxicant MPP(+).
abstract: Assessment of the network of toxicity pathways by Omics technologies and bioinformatic data processing paves the road toward a new toxicology for the twenty-first century. Especially, the upstream network of responses, taking place in toxicant-treated cells before a point of no return is reached, is still little explored. We studied the effects of the model neurotoxicant 1-methyl-4-phenylpyridinium (MPP(+)) by a combined metabolomics (mass spectrometry) and transcriptomics (microarrays and deep sequencing) approach to provide unbiased data on earliest cellular adaptations to stress. Neural precursor cells (LUHMES) were differentiated to homogeneous cultures of fully postmitotic human dopaminergic neurons, and then exposed to the mitochondrial respiratory chain inhibitor MPP(+) (5 μM). At 18-24 h after treatment, intracellular ATP and mitochondrial integrity were still close to control levels, but pronounced transcriptome and metabolome changes were seen. Data on altered glucose flux, depletion of phosphocreatine and oxidative stress (e.g., methionine sulfoxide formation) confirmed the validity of the approach. New findings were related to nuclear paraspeckle depletion, as well as an early activation of branches of the transsulfuration pathway to increase glutathione. Bioinformatic analysis of our data identified the transcription factor ATF-4 as an upstream regulator of early responses. Findings on this signaling pathway and on adaptive increases of glutathione production were confirmed biochemically. Metabolic and transcriptional profiling contributed complementary information on multiple primary and secondary changes that contribute to the cellular response to MPP(+). Thus, combined 'Omics' analysis is a new unbiased approach to unravel earliest metabolic changes, whose balance decides on the final cell fate.
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: A K
authors.initials: AK
authors.lastname: Krug
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Gutbier
authors.affiliation: Center for Alternatives to Animal Testing (CAAT-US), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
authors.forename: L
authors.initials: L
authors.lastname: Zhao
authors.affiliation: 1] Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany [2] Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Pöltl
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Kullmann
authors.affiliation: 1] Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany [2] Nycomed Chair for Bioinformatics and Information Mining, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Ivanova
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Förster
authors.affiliation: Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne, Cologne D-50931, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Jagtap
authors.affiliation: Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, Esch-Belval L-4362, Luxembourg.
authors.forename: J
authors.initials: J
authors.lastname: Meiser
authors.affiliation: Boehringer Ingelheim Pharma GmbH & Co. KG Div. Research, Ingelheim, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Leparc
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Schildknecht
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Adam
authors.affiliation: Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Campus Belval, Esch-Belval L-4362, Luxembourg.
authors.forename: K
authors.initials: K
authors.lastname: Hiller
authors.affiliation: Biotechnology Institute Thurgau at the University of Konstanz, Kreuzlingen CH-8280, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Farhan
authors.affiliation: Chair of Biochemical Pharmacology, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Brunner
authors.affiliation: Center for Alternatives to Animal Testing (CAAT-US), Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
authors.forename: T
authors.initials: T
authors.lastname: Hartung
authors.affiliation: Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne, Cologne D-50931, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Sachinidis
authors.affiliation: Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Leist
mesh_terms: D015655:1-Methyl-4-phenylpyridinium / Q000633:toxicity*; D051701:Activating Transcription Factor 4 / Q000235:genetics / Q000378:metabolism; D000222:Adaptation, Physiological; D000255:Adenosine Triphosphate / Q000378:metabolism; D002460:Cell Line; D019295:Computational Biology; D059290:Dopaminergic Neurons / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004734:Energy Metabolism / Q000187:drug effects*; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation; D005947:Glucose / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D013058:Mass Spectrometry; D055432:Metabolomics / Q000379:methods; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D058953:Neural Stem Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D020258:Neurotoxicity Syndromes / Q000209:etiology* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics; D010725:Phosphocreatine / Q000378:metabolism; D034622:RNA Interference; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects*; D014162:Transfection
chemical_list: C497109:ATF4 protein, human; D010725:Phosphocreatine; D051701:Activating Transcription Factor 4; D000255:Adenosine Triphosphate; D005978:Glutathione; D005947:Glucose; D015655:1-Methyl-4-phenylpyridinium