title: [Roles of PKCβ/P66Shc oxidative stress signal pathway in mediating hyperoxia-induced ROS production in alveolar epithelial cells].
abstract: OBJECTIVE
  To explore the roles of PKCβ/P66Shc oxidative stress signal pathway in mediating hyperoxia-induced reactive oxgen species (ROS) production in alveolar epithelial cells (A549) and the protective effects of PKCβ inhibitor on hyperoxia-induced injuries of alveolar epithelial cells.
  
  
  METHODS
  A549 cells were cultured in vitro and randomly divided into three groups: control, hyperoxia and PKCβ inhibitor LY333531 treatment. The hyperoxia group was exposed to a mixture of O2 (950 mL/L) and CO2 (50 mL/L) for 10 minutes and then cultured in a closed environment. The LY333531 group was treated with PKCβ inhibitor LY333531 of 10 µmol/L for 24 hours before hyperoxia induction. Cells were collected 24 hours after culture and the levels of PKCβ, Pin1, P66Shc and P66Shc-Ser36 were detected by Western blot. The intracellular translocation of P66Shc, the production of ROS and cellular mitochondria membrane potential were measured using the confocal microscopy.
  
  
  RESULTS
  Compared with the control group, the levels of PKCβ, Pin1, P66Shc and P-P66Shc-Ser36 in A549 cells 24 hours after culture increased significantly in the hyperoxia group. These changes in the hyperoxia group were accompanied with an increased translocation rate of P66Shc from cytoplasm into mitochondria, an increased production of mitochondrial ROS, and a reduced mitochondrial membrane potential. Compared with the hyperoxia group, the levels of Pin1, P66Shc and P66Shc-Ser36 in A549 cells, the translocation rate of P66Shc from cytoplasm into mitochondria and the production of mitochondrial ROS decreased significantly, while the mitochondrial membrane potential increased significantly in the LY333531 treatment group. However, there were significant differences in the above mentioned measurements between the LY333531 treatment and control groups.
  
  
  CONCLUSIONS
  Hyperoxia can increase the expression of PKCβ in alveolar epithelial cells and production of mitochondrial ROS and decrease mitochondrial membrane potential. PKCβ inhibitor LY333531 can partially disrupt these changes and thus alleviate the hyperoxia-induced alveolar epithelial cell injury.
authors: Department of Neonatology, Affiliated Hospital of Luzhou Medical College, Luzhou, Sichuan 646000, China. dongwenbin2000@163.com.
authors: Zhong-Li
authors: ZL
authors: Che
authors: Wen-Bin
authors: WB
authors: Dong
authors: Qing-Ping
authors: QP
authors: Li
authors: Xiao-Ping
authors: XP
authors: Lei
authors: Lan
authors: L
authors: Kang
authors: Lin
authors: L
authors: Guo
authors: Xue-Song
authors: XS
authors: Zhai
authors: Feng
authors: F
authors: Chen
mesh_terms: D015687:Cell Hypoxia; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008301:Maleimides / Q000494:pharmacology; D018384:Oxidative Stress; D064546:Protein Kinase C beta / Q000502:physiology*; D011650:Pulmonary Alveoli / Q000166:cytology / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D055765:Shc Signaling Adaptor Proteins / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1
chemical_list: D007211:Indoles; D008301:Maleimides; D017382:Reactive Oxygen Species; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; C099154:ruboxistaurin; D064546:Protein Kinase C beta