title: Radioprotective effect of adenine on irradiation-induced apoptosis.
abstract: OBJECTIVE
  To investigate the radioprotective effect of adenine on irradiated lymphocytes and discover the possible mechanisms of protection.
  
  
  METHODS
  Lymphocytes were pretreated for 12 h with adenine (0.001-0.1 μmol·L(-1)) and then exposed to 4 Gy radiation. Cell viability was observed by the MTS assay, apoptosis was detected by Annexin V-FITC/PI, DNA ladder, and caspase 3/7 activity. Caspase-9, Bax, and Bcl-2 gene expression was investigated by RT-PCR.
  
  
  RESULTS
  Irradiation increased cell death and DNA fragmentation. Pretreatment with adenine significantly reversed this tendency. Furthermore, several anti-apoptotic characteristics of adenine were determined, including the ability to inhibit caspase 3/7, upregulate B-cell lymphoma (Bcl-2) and downregulate Bcl-2- associated X (Bax), capase-9 gene expression in 4 Gy-irradiated AHH-1 cells.
  
  
  CONCLUSIONS
  The results suggest that adenine had a radioprotective effect to inhibit apoptosis in a concentration dependent manner.
authors.affiliation: Institute of Radiation Medicine, Academy of Military Medical Science, Beijing 100850, China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Wang
authors.forename: Zeng-Chun
authors.initials: ZC
authors.lastname: Ma
authors.forename: Shuai
authors.initials: S
authors.lastname: Shao
authors.forename: Qian
authors.initials: Q
authors.lastname: Hong
authors.forename: Yu-Guang
authors.initials: YG
authors.lastname: Wang
authors.forename: Hong-Ling
authors.initials: HL
authors.lastname: Tan
authors.forename: Xiao-Qin
authors.initials: XQ
authors.lastname: Lu
authors.forename: Zhi
authors.initials: Z
authors.lastname: Dong
authors.forename: Yue
authors.initials: Y
authors.lastname: Gao
mesh_terms: D000225:Adenine / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects* / Q000528:radiation effects*; D053453:Caspase 9 / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D005720:Gamma Rays; D015870:Gene Expression / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000528:radiation effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D011837:Radiation-Protective Agents; D051028:bcl-2-Associated X Protein; D053453:Caspase 9; D000225:Adenine