Changes in protein expression in rat bronchoalveolar lavage fluid after exposure to zinc oxide nanoparticles: an iTRAQ proteomic approach.

RATIONALEZinc oxide nanoparticles (ZnO NPs) are widely used in consumer products and various biomedical fields. As a result, humans are frequently exposed to these NPs. However, there is a lack of information about the proteins that are expressed in the airway in response to exposure to ZnO NPs. METHODSBronchoalveolar lavage fluid (BALF) from Sprague-Dawley (SD) rats that had been exposed to high-dose 35 nm ZnO NPs (N = 6) and filtered air (N = 4) was collected and then labeled with isobaric tags for relative and absolute quantitation (iTRAQ). The differentially expressed proteins were identified by two-dimensional liquid chromatography/tandem mass spectrometry (2D-LC/MS/MS) and further classified by Gene Ontology (GO) annotation. RESULTSA total of 46 proteins displayed significant changes after exposure. GO annotation of these differentially expressed proteins indicated that exposure to ZnO NPs mainly affected immune and inflammatory processes. Furthermore, S100A8 and S100A9, candidate markers of idiopathic pulmonary fibrosis and lung cancer, were significantly up-regulated (2.78- and 2.87-fold, respectively) following exposure. CONCLUSIONSOur data are consistent with recent study results that exposure to ZnO NPs induces lung inflammation. These data contribute to a better understanding of how exposure to ZnO NPs leads to lung damage through the functional classification of these proteins. Copyright (c) 2014 John Wiley & Sons, Ltd.