title: Proteomic changes in human lung epithelial cells (A549) in response to carbon black and titanium dioxide exposures.
abstract: This study combined cytotoxicity assays with proteomic analysis to characterize the unique biological responses of the A549 human lung epithelial cell line to two physicochemically distinct respirable particles titanium dioxide (TiO2) and carbon black (CB). Cellular LDH, ATP, BrdU incorporation and resazurin reduction indicated that CB was more potent than TiO2. Proteomic analysis was done using 2D-GE and MALDI-TOF-TOF-MS. Proteomic changes reflected common and particle-specific responses. Particle-specific proteomic responses were associated with cell death (necrosis and apoptosis), viability and proliferation pathways. Our results suggested that these pathways were consistent with the cytotoxicity data. For instance, increased expressions of anti-proliferative proteins LMNA and PA2G4 were in agreement with the decreased BrdU incorporation in A549 cells after exposure to CB. Similarly, increased expression of HSPA5 that is associated with ATPase activity was consistent with decreased cellular ATP levels in these cells. These findings reveal that proteomic changes can explain the cellular cytotoxicity characteristics of the particles. In essence, our results demonstrate that the in vitro toxicoproteomic approach is a promising tool to gain insight into molecular mechanisms underlying particle exposure-specific cytotoxicity.
  
  
  
  In this study we have shown that toxicoproteomics is a sensitive and informative method to resolve the toxicity characteristics of particles with different physicochemical properties. This approach can be useful in the investigation of molecular mechanisms underpinning cellular cytotoxic responses elicited by particle exposures. Thus, the toxicoproteomic approach can be valuable in assessing the risk associated with particle exposures in vitro.
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada; Department of Biochemistry, Faculty of Science, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
authors.forename: Ngoc Q
authors.initials: NQ
authors.lastname: Vuong
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: Goegan
authors.affiliation: Analytical Biochemistry and Proteomics, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Susantha
authors.initials: S
authors.lastname: Mohottalage
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Dalibor
authors.initials: D
authors.lastname: Breznan
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Marianne
authors.initials: M
authors.lastname: Ariganello
authors.affiliation: Biostatistics Section, Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Williams
authors.affiliation: Analytical Biochemistry and Proteomics, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Fred
authors.initials: F
authors.lastname: Elisma
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada.
authors.forename: Subramanian
authors.initials: S
authors.lastname: Karthikeyan
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada; Department of Biochemistry, Faculty of Science, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
authors.forename: Renaud
authors.initials: R
authors.lastname: Vincent
authors.affiliation: Analytical Biochemistry and Proteomics, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada. Electronic address: premkumari.kumarathasan@canada.ca.
authors.forename: Premkumari
authors.initials: P
authors.lastname: Kumarathasan
mesh_terms: D000072283:A549 Cells; D048868:Adaptor Proteins, Signal Transducing / Q000032:analysis / Q000378:metabolism; D056809:Alveolar Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D000704:Analysis of Variance; D002470:Cell Survival / Q000187:drug effects; D015180:Electrophoresis, Gel, Two-Dimensional; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins / Q000032:analysis / Q000378:metabolism; D006801:Humans; D034904:Lamin Type A / Q000032:analysis / Q000378:metabolism; D010316:Particle Size; D011506:Proteins / Q000032:analysis*; D040901:Proteomics / Q000379:methods*; D016601:RNA-Binding Proteins / Q000032:analysis / Q000378:metabolism; D053260:Soot / Q000633:toxicity*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013473:Sunscreening Agents / Q000633:toxicity*; D014025:Titanium / Q000633:toxicity*; D018675:Toxicity Tests
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; C494847:LMNA protein, human; D034904:Lamin Type A; C101633:PA2G4 protein, human; D011506:Proteins; D016601:RNA-Binding Proteins; D053260:Soot; D013473:Sunscreening Agents; C009495:titanium dioxide; D014025:Titanium
keywords: 2D-GE; A549; Carbon black; Cytotoxicity assay; Titanium dioxide; Toxicoproteomics