title: Toxicological profile of small airway epithelial cells exposed to gold nanoparticles.
abstract: Gold nanoparticles (AuNPs) have diverse applications in the biomedical industry such as in diagnosis, labeling, delivering and sensing. Despite their prevalent medical use, nanotoxicity induced by AuNPs is still largely unknown. We have previously shown that AuNPs could exert cytotoxic effects on lung fibroblasts. In this study, we investigated the in vitro toxicological effects of AuNPs in small airway epithelial cells (SAECs) which are the first cells of contact for inhaled NPs and compared expression of metallothionein (MT), a reactive oxygen species scavenger, in SAECs and lung fibroblasts in vitro. Transmission electron microscopy (TEM) and energy-dispersive X-ray (EDX) spectroscopy study revealed cellular uptake of aggregates of AuNPs into the cytoplasm at the ultrastructural level. A significant increase in lipid peroxide as well as substantial DNA damage and cytotoxicity was observed in AuNP-treated cells. For MT expression, AuNPs induced down-regulation of the MT-1X isoform in SAECs, but up-regulation of the MT-1X and MT-2 A isoforms in MRC5 lung fibroblasts. The present study suggests that AuNPs could induce oxidative stress-related cytotoxicity and genotoxicity in SAECs.
authors.affiliation: Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, S117597 Singapore.
authors.forename: Cheng-Teng
authors.initials: CT
authors.lastname: Ng
authors.forename: Jasmine Jia'en
authors.initials: JJ
authors.lastname: Li
authors.forename: Resham Lal
authors.initials: RL
authors.lastname: Gurung
authors.forename: Manoor Prakash
authors.initials: MP
authors.lastname: Hande
authors.forename: Choon-Nam
authors.initials: CN
authors.lastname: Ong
authors.forename: Boon-Huat
authors.initials: BH
authors.lastname: Bay
authors.forename: Lin-Yue Lanry
authors.initials: LY
authors.lastname: Yung
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D020552:Comet Assay; D004847:Epithelial Cells / Q000187:drug effects*; D005347:Fibroblasts / Q000187:drug effects; D006046:Gold / Q000633:toxicity*; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects*; D053768:Metal Nanoparticles / Q000633:toxicity*; D008668:Metallothionein / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D018384:Oxidative Stress / Q000187:drug effects; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D006046:Gold; D008668:Metallothionein
keywords: DNA damage; Gold nanoparticles; cytotoxicity and genotoxicity; lung; metallothionein (MT); oxidative stress