title: Molecular hydrogen protects human lymphocyte AHH-1 cells against 12C6+ heavy ion radiation.
abstract: OBJECTIVE
  To investigate the potential protective role of molecular hydrogen (H(2)) against (12)C(6+) heavy ion radiation, which is a major hazard for space travel and has been also widely used in heavy ion radiotherapy.
  
  
  METHODS
  H(2) was dissolved in Roswell Park Memorial Institute (RPMI) 1640 medium under high pressure (0.4 Mpa) to a saturated level by using an apparatus produced by our department. A 2-[6-(4'-hydroxy) phenoxy-3H-xanthen-3-on-9-yl] benzoate (HPF) probe and a 2',7'-Dichlorodihydrofluorescein diacetate (H2DCFH-DA) fluorescent dye were used to measure the intracellular reactive oxygen species (ROS) level. Cell apoptosis were determined by double-staining with Annexin V-fluorescein isothiocyanate (Annexin V-FITC) and propidium iodide (PI) as well as a Hoechst 33342 staining method alternatively. Subsequently, cell cycle analysis was performed using a PI staining method and the expression of apoptotic protein was examined by Western blot.
  
  
  RESULTS
  In this study, we demonstrated H(2) reduced ROS level in Human lymphocyte AHH-1 cells as well as in the radiolysis of water. Our data also showed H(2) attenuated (12)C(6+) radiation- induced cell apoptosis and also alleviated radiation-induced G2/M cell cycle arrest. Heavy ion radiation-induced Caspase 3 activation was also inhibited by H(2) treatment.
  
  
  CONCLUSIONS
  In conclusion, these data showed that H(2) attenuated (12)C(6+) radiation-induced cell apoptosis through reducing the ROS level and modulating apoptotic molecules, thus indicating the potential of H(2) as a safe and effective radioprotectant.
authors.affiliation: Department of Radiation Medicine, Faculty of Naval Medicine, Second Military Medical University , Shanghai , P. R. China.
authors.forename: Yanyong
authors.initials: Y
authors.lastname: Yang
authors.forename: Fu
authors.initials: F
authors.lastname: Gao
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang
authors.forename: Yijuan
authors.initials: Y
authors.lastname: Hunag
authors.forename: Pei
authors.initials: P
authors.lastname: Zhang
authors.forename: Cong
authors.initials: C
authors.lastname: Liu
authors.forename: Bailong
authors.initials: B
authors.lastname: Li
authors.forename: Jianming
authors.initials: J
authors.lastname: Cai
mesh_terms: D017209:Apoptosis; D002244:Carbon / Q000737:chemistry*; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D059565:G2 Phase Cell Cycle Checkpoints / Q000528:radiation effects; D020450:Heavy Ions; D006801:Humans; D006859:Hydrogen / Q000737:chemistry*; D008214:Lymphocytes / Q000528:radiation effects*; D011837:Radiation-Protective Agents / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000378:metabolism; D014867:Water / Q000737:chemistry
chemical_list: D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; D014867:Water; D002244:Carbon; D006859:Hydrogen; C505407:CASP3 protein, human; D053148:Caspase 3