title: Systems biology approach for evaluating the biological impact of environmental toxicants in vitro.
abstract: Exposure to cigarette smoke is a leading cause of lung diseases including chronic obstructive pulmonary disease and cancer. Cigarette smoke is a complex aerosol containing over 6000 chemicals and thus it is difficult to determine individual contributions to overall toxicity as well as the molecular mechanisms by which smoke constituents exert their effects. We selected three well-known harmful and potentially harmful constituents (HPHCs) in tobacco smoke, acrolein, formaldehyde and catechol, and established a high-content screening method using normal human bronchial epithelial cells, which are the first bronchial cells in contact with cigarette smoke. The impact of each HPHC was investigated using 13 indicators of cellular toxicity complemented with a microarray-based whole-transcriptome analysis followed by a computational approach leveraging mechanistic network models to identify and quantify perturbed molecular pathways. HPHCs were evaluated over a wide range of concentrations and at different exposure time points (4, 8, and 24 h). By high-content screening, the toxic effects of the three HPHCs could be observed only at the highest doses. Whole-genome transcriptomics unraveled toxicity mechanisms at lower doses and earlier time points. The most prevalent toxicity mechanisms observed were DNA damage/growth arrest, oxidative stress, mitochondrial stress, and apoptosis/necrosis. A combination of multiple toxicological end points with a systems-based impact assessment allows for a more robust scientific basis for the toxicological assessment of HPHCs, allowing insight into time- and dose-dependent molecular perturbations of specific biological pathways. This approach allowed us to establish an in vitro systems toxicology platform that can be applied to a broader selection of HPHCs and their mixtures and can serve more generally as the basis for testing the impact of other environmental toxicants on normal bronchial epithelial cells.
authors.affiliation: Philip Morris International R&D, Philip Morris Products S.A. , Quai Jeanrenaud 5, 2000 Neuchâtel, Switzerland.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Gonzalez-Suarez
authors.forename: Alain
authors.initials: A
authors.lastname: Sewer
authors.forename: Paul
authors.initials: P
authors.lastname: Walker
authors.forename: Carole
authors.initials: C
authors.lastname: Mathis
authors.forename: Samantha
authors.initials: S
authors.lastname: Ellis
authors.forename: Heather
authors.initials: H
authors.lastname: Woodhouse
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Guedj
authors.forename: Remi
authors.initials: R
authors.lastname: Dulize
authors.forename: Diego
authors.initials: D
authors.lastname: Marescotti
authors.forename: Stefano
authors.initials: S
authors.lastname: Acali
authors.forename: Florian
authors.initials: F
authors.lastname: Martin
authors.forename: Nikolai V
authors.initials: NV
authors.lastname: Ivanov
authors.forename: Julia
authors.initials: J
authors.lastname: Hoeng
authors.forename: Manuel C
authors.initials: MC
authors.lastname: Peitsch
mesh_terms: D000171:Acrolein / Q000737:chemistry / Q000633:toxicity; D017209:Apoptosis / Q000187:drug effects; D002396:Catechols / Q000737:chemistry / Q000633:toxicity; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004249:DNA Damage / Q000187:drug effects; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects; D005557:Formaldehyde / Q000737:chemistry / Q000633:toxicity; D020869:Gene Expression Profiling; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D012906:Smoke
chemical_list: D002396:Catechols; D017382:Reactive Oxygen Species; D012906:Smoke; D005557:Formaldehyde; D000171:Acrolein; D020929:Mitogen-Activated Protein Kinase Kinases; C034221:catechol