title: Mechanistic toxicity evaluation of uncoated and PEGylated single-walled carbon nanotubes in neuronal PC12 cells.
abstract: We investigated and compared the concentration-dependent cytotoxicity of single-walled carbon nanotubes (SWCNTs) and SWCNTs functionalized with polyethylene glycol (SWCNT-PEGs) in neuronal PC12 cells at the biochemical, cellular, and gene expressional levels. SWCNTs elicited cytotoxicity in a concentration-dependent manner, and SWCNT-PEGs exhibited less cytotoxic potency than uncoated SWCNTs. Reactive oxygen species (ROS) were generated in both a concentration- and surface coating-dependent manner after exposure to these nanomaterials, indicating different oxidative stress mechanisms. More specifically, gene expression analysis showed that the genes involved in oxidoreductases and antioxidant activity, nucleic acid or lipid metabolism, and mitochondria dysfunction were highly represented. Interestingly, alteration of the genes is also surface coating-dependent with a good correlation with the biochemical data. These findings suggest that surface functionalization of SWCNTs decreases ROS-mediated toxicological response in vitro.
authors.affiliation: National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, Arkansas 72079, USA.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Chen
authors.forename: Susan M
authors.initials: SM
authors.lastname: Lantz
authors.forename: Paul C
authors.initials: PC
authors.lastname: Howard
authors.forename: Merle G
authors.initials: MG
authors.lastname: Paule
authors.forename: William
authors.initials: W
authors.lastname: Slikker
authors.forename: Fumiya
authors.initials: F
authors.lastname: Watanabe
authors.forename: Thikra
authors.initials: T
authors.lastname: Mustafa
authors.forename: Alexandru S
authors.initials: AS
authors.lastname: Biris
authors.forename: Syed F
authors.initials: SF
authors.lastname: Ali
mesh_terms: D000818:Animals; D037742:Nanotubes, Carbon; D009474:Neurons / Q000187:drug effects*; D018384:Oxidative Stress; D016716:PC12 Cells; D011092:Polyethylene Glycols / Q000737:chemistry*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species; D011092:Polyethylene Glycols