title: Single-walled carbon nanotubes downregulate stress-responsive genes in human respiratory tract cells.
abstract: Carbon nanotubes (CNTs) are currently key promising materials of nanotechnology. However, elucidation of the possible effects of CNTs on the respiratory tract is urgently needed. The present study aimed to clarify the effect of single-walled CNTs (SWCNTs) on the expression of stress-responsive genes, using primary cultured normal human bronchial epithelial (NHBE), diseased HBE (DHBE) cells, and the human carcinoma cell lines A549 and FaDu. Purified SWCNTs were applied at concentrations of 0.1 or 1.0 mg/mL for 6 h, and a polymerase chain reaction (PCR) array was conducted to examine 84 stress-responsive genes. NHBE cell exposure to SWCNTs resulted in global downregulation of genes involved in inflammation, oxidative stress, and apoptosis. Further analysis using DHBE cells and carcinoma cell lines indicated a similar trend, although differences in sensitivity were observed. Downregulation of stress-responsive genes may be involved in the mechanism by which stress response protects against lung injury.
authors.affiliation: Pharmaceutics, Faculty of Pharmacy, Meijo University, Nagoya, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Hitoshi
authors.forename: Miki
authors.initials: M
authors.lastname: Katoh
authors.forename: Tomoko
authors.initials: T
authors.lastname: Suzuki
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ando
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nadai
mesh_terms: D017209:Apoptosis / Q000502:physiology; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000633:toxicity*; D018384:Oxidative Stress / Q000502:physiology; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012137:Respiratory System / Q000166:cytology
chemical_list: D037742:Nanotubes, Carbon; D012333:RNA, Messenger