title: Diazoxide protects L6 skeletal myoblasts from H2O2-induced apoptosis via the phosphatidylinositol-3 kinase/Akt pathway.
abstract: OBJECTIVE
  Transplanted cell survival might greatly improve the therapeutic efficacy of cell therapy. Diazoxide (DZ), a highly selective mitochondrial ATP-sensitive potassium channel opener, is known to suppress cell apoptosis and protect cells in oxidative stressed ischemic environment. We explored the mechanisms involved in DZ pre-treatment-induced anti-apoptotic effect on L6 skeletal myoblast (SKM).
  
  
  METHODS
  L6 SKMs were divided into control group, H2O2 group, DZ + H2O2 group and DZ + LY + H2O2 group. Treatments of 400 μmol/L H2O2 for 24 h alone, or after 200 μmol/L DZ pre-treatment for 30 min, or after DZ and 50 μmol/L LY294002 co-administration for 30 min were performed. The cell apoptosis rates were assessed by flow cytometric analysis. The changes of mitochondrial membrane potential were determined by JC-1 mitochondrial staining. The activation of phosphatidylinositol-3 kinase (PI3K)/Akt, caspase-9 and caspase-3 was detected by western blot.
  
  
  RESULTS
  Compared with the H2O2 group, DZ pre-treatment protected cells from H2O2-induced damage, increased Akt phosphorylation, prevented mitochondrial membrane depolarization as well as the activation of caspase-9 and caspase-3 and decreased the cell apoptosis rate. However, the DZ-induced cytoprotective and anti-apoptosis effects were partly inhibited by co-administration of a PI3K inhibitor, LY294002.
  
  
  CONCLUSIONS
  These data suggest that DZ pre-treatment contributes to protection of L6 SKMs against apoptosis at least partly by activating the PI3K/Akt pathway and subsequently inhibiting the mitochondrial-mediated caspase-dependent apoptotic signalling pathway.
authors.affiliation: Department of Histology and Embryology, Basic Medical College, Hebei Medical University, Zhongshan East Road 361, Shijiazhuang City, 050017, Hebei Province, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Endocrinology, The 3rd Hospital of Hebei Medical University, Ziqiang Road 139, Shijiazhuang City, Hebei Province, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Histology and Embryology, Basic Medical College, Hebei Medical University, Zhongshan East Road 361, Shijiazhuang City, 050017, Hebei Province, People's Republic of China.
authors.forename: Guoyu
authors.initials: G
authors.lastname: Xue
authors.affiliation: Department of Histology and Embryology, Basic Medical College, Hebei Medical University, Zhongshan East Road 361, Shijiazhuang City, 050017, Hebei Province, People's Republic of China.
authors.forename: Lisi
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Histology and Embryology, Basic Medical College, Hebei Medical University, Zhongshan East Road 361, Shijiazhuang City, 050017, Hebei Province, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Histology and Embryology, Basic Medical College, Hebei Medical University, Zhongshan East Road 361, Shijiazhuang City, 050017, Hebei Province, People's Republic of China. shaosuxia1202@126.com.
authors.forename: Suxia
authors.initials: S
authors.lastname: Shao
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D002460:Cell Line; D002867:Chromones / Q000494:pharmacology; D003981:Diazoxide / Q000494:pharmacology*; D004232:Diuretics / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D009025:Morpholines / Q000494:pharmacology; D018482:Muscle, Skeletal / Q000166:cytology / Q000187:drug effects; D032446:Myoblasts / Q000187:drug effects*; D051058:Oncogene Protein v-akt / Q000187:drug effects*; D016877:Oxidants / Q000633:toxicity*; D019869:Phosphatidylinositol 3-Kinases / Q000187:drug effects*
chemical_list: D002867:Chromones; D004232:Diuretics; D009025:Morpholines; D016877:Oxidants; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D006861:Hydrogen Peroxide; D019869:Phosphatidylinositol 3-Kinases; D051058:Oncogene Protein v-akt; D020169:Caspases; D003981:Diazoxide
keywords: Apoptosis; Apoptotic signalling pathway; Diazoxide; Phosphatidylinositol-3 kinase/Akt pathway; Skeletal myoblast