title: [Effect of toluene diisocyanate on reactive oxygen species production and permeability of human bronchial epithelial cells in vitro].
abstract: OBJECTIVE
  To investigate the effect of toluene diisocyanate (TDI) on the production of reactive oxygen species (ROS) and the permeability of human bronchial epithelial (HBE) cells.
  
  
  METHODS
  TDI-human serum albumin (TDI-HSA) conjugate was prepared using a modified Son's method. MTT assay was used to assess HBE cell viability after exposure to different concentrations of TDI-HSA. The level of intracellular ROS of HBE cells was detected by flow cytometry with an oxidation-sensitive fluorescent probe 2',7'-dichlorofluorescein diacetate (DCFH-DA) uploading, and the permeability of cell monolayer was assessed by detecting the transepithelial electrical resistance (TEER).
  
  
  RESULTS
  The exposure to 120 µg/ml TDI-HSA did not obviously affect the cell viability. Compared with the control group, the intracellular fluorescent intensity increased significantly in the cells exposed to 20, 60, and 100 µg/ml TDI-HSA (P<0.05). The intracellular ROS production increased significantly after 100 µg/ml TDI-HSA treatment (P<0.05), but the increment in ROS production was significantly suppressed by pretreatment of the cells with N-acetylcysteine (NAC) (P<0.05), which also enhanced the TEER decreased by TDI-HSA treatment (P<0.05).
  
  
  CONCLUSIONS
  TDI enhances the permeability of HBE cell monolayer partially through a ROS-mediated pathway, suggesting the importance of oxidative stress in TDI-induced pulmonary diseases.
authors.affiliation: Department of Respiratory Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China. moguanwencoco@qq.com
authors.forename: Guan-wen
authors.initials: GW
authors.lastname: Mo
authors.forename: Shao-xi
authors.initials: SX
authors.lastname: Cai
authors.forename: Hai-jin
authors.initials: HJ
authors.lastname: Zhao
authors.forename: Wen-jun
authors.initials: WJ
authors.lastname: Li
authors.forename: Wan-cheng
authors.initials: WC
authors.lastname: Tong
authors.forename: Lai-yu
authors.initials: LY
authors.lastname: Liu
mesh_terms: D001980:Bronchi / Q000166:cytology*; D002460:Cell Line; D002463:Cell Membrane Permeability / Q000187:drug effects*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012709:Serum Albumin / Q000494:pharmacology; D014051:Toluene 2,4-Diisocyanate / Q000494:pharmacology*
chemical_list: D017382:Reactive Oxygen Species; D012709:Serum Albumin; D014051:Toluene 2,4-Diisocyanate