title: Pathway and time-resolved benzo[a]pyrene toxicity on Hepa1c1c7 cells at toxic and subtoxic exposure.
abstract: Benzo[a]pyrene (B[a]P) is an environmental contaminant mainly studied for its toxic/carcinogenic effects. For a comprehensive and pathway orientated mechanistic understanding of the effects directly triggered by a toxic (5 μM) or a subtoxic (50 nM) concentration of B[a]P or indirectly by its metabolites, we conducted time series experiments for up to 24 h to study the effects in murine hepatocytes. These cells rapidly take up and actively metabolize B[a]P, which was followed by quantitative analysis of the concentration of intracellular B[a]P and seven representative degradation products. Exposure with 5 μM B[a]P led to a maximal intracellular concentration of 1604 pmol/5 × 10(4) cells, leveling at 55 pmol/5 × 10(4) cells by the end of the time course. Changes in the global proteome (>1000 protein profiles) and metabolome (163 metabolites) were assessed in combination with B[a]P degradation. Abundance profiles of 236 (both concentrations), 190 (only 5 μM), and 150 (only 50 nM) proteins were found to be regulated in response to B[a]P in a time-dependent manner. At the endogenous metabolite level amino acids, acylcarnitines and glycerophospholipids were particularly affected by B[a]P. The comprehensive chemical, proteome and metabolomic data enabled the identification of effects on the pathway level in a time-resolved manner. So in addition to known alterations, also protein synthesis, lipid metabolism, and membrane dysfunction were identified as B[a]P specific effects.
authors.affiliation: Department of Proteomics, UFZ, Helmholtz-Centre for Environmental Research , Permoserstr. 15, 04318 Leipzig, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kalkhof
authors.forename: Franziska
authors.initials: F
authors.lastname: Dautel
authors.forename: Salvatore
authors.initials: S
authors.lastname: Loguercio
authors.forename: Sven
authors.initials: S
authors.lastname: Baumann
authors.forename: Saskia
authors.initials: S
authors.lastname: Trump
authors.forename: Harald
authors.initials: H
authors.lastname: Jungnickel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Otto
authors.forename: Susanne
authors.initials: S
authors.lastname: Rudzok
authors.forename: Sarah
authors.initials: S
authors.lastname: Potratz
authors.forename: Andreas
authors.initials: A
authors.lastname: Luch
authors.forename: Irina
authors.initials: I
authors.lastname: Lehmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Beyer
authors.forename: Martin
authors.initials: M
authors.lastname: von Bergen
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001564:Benzo(a)pyrene / Q000378:metabolism / Q000633:toxicity*; D050260:Carbohydrate Metabolism / Q000187:drug effects; D045744:Cell Line, Tumor; D004785:Environmental Pollutants / Q000378:metabolism / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects; D050356:Lipid Metabolism / Q000187:drug effects; D053858:Metabolic Networks and Pathways; D055442:Metabolome; D051379:Mice; D020543:Proteome / Q000235:genetics / Q000378:metabolism
chemical_list: D000596:Amino Acids; D004785:Environmental Pollutants; D020543:Proteome; D001564:Benzo(a)pyrene
keywords: B[a]P metabolites; Benzo[a]pyrene (B[a]P); Hepa1c1c7 cells; SILAC; aryl hydrocarbon receptor (Ahr); metabolomics; oxidative stress; protein expression analysis; proteomics