title: Adaptive response in mice exposed to 900 MHZ radiofrequency fields: bleomycin-induced DNA and oxidative damage/repair.
abstract: OBJECTIVE
  To determine whether mice exposed to radiofrequency fields (RF) and then injected with a radiomimetic drug, bleomycin (BLM), exhibit adaptive response and provide some mechanistic evidence for such response.
  
  
  METHODS
  Adult mice were exposed to 900 MHz RF at 120 μW/cm(2) power density for 4 hours/day for 7 days. Immediately after the last exposure, some mice were sacrificed while the others were injected with BLM 4 h later. In each animal: (i) The primary DNA damage and BLM-induced damage as well as its repair kinetics were determined in blood leukocytes; and (ii) the oxidative damage was determined from malondialdehyde (MDA) levels and the antioxidant status was assessed from superoxide dismutase (SOD) levels in plasma, liver and lung tissues.
  
  
  RESULTS
  There were no indications for increased DNA and oxidative damages in mice exposed to RF alone in contrast to those treated with BLM alone. Mice exposed to RF+ BLM showed significantly: (a) reduced BLM-induced DNA damage and that remained after each 30, 60, 90, 120 and 150 min repair time, and (b) decreased levels of MDA in plasma and liver, and increased SOD level in the lung.
  
  
  CONCLUSIONS
  The overall data suggested that RF exposure was capable of inducing adaptive response and mitigated BLM- induced DNA and oxidative damages by activating certain cellular processes.
authors.affiliation: School of Public Health, Medical College of Soochow University , Suzhou, Jiangsu.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Zong
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Ji
authors.forename: Qina
authors.initials: Q
authors.lastname: He
authors.forename: Shunxing
authors.initials: S
authors.lastname: Zhu
authors.forename: Fenju
authors.initials: F
authors.lastname: Qin
authors.forename: Jian
authors.initials: J
authors.lastname: Tong
authors.forename: Yi
authors.initials: Y
authors.lastname: Cao
mesh_terms: D000222:Adaptation, Physiological / Q000528:radiation effects; D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects; D001761:Bleomycin / Q000009:adverse effects*; D004249:DNA Damage; D004260:DNA Repair; D007700:Kinetics; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D011836:Radiation Tolerance; D011846:Radio Waves / Q000009:adverse effects*; D011853:Radiobiology; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D001761:Bleomycin; D008315:Malondialdehyde; D013482:Superoxide Dismutase
keywords: DNA damage/repair; Radiofrequency fields; adaptive response; bleomycin; mice; oxidative damage/repair