Radioprotection by vitamin E: injectable vitamin E administered alone or with WR-3689 enhances survival of irradiated mice.
Radioprotection by injectable vitamin E (alpha-tocopherol) was investigated in mice exposed to 60Co radiation (0.2 Gy/min). Vitamin E injected subcutaneously either 1 hr before or within 15 min after irradiation significantly increased 30-day postirradiation survival in CD2F1 male mice. A dose reduction factor (DRF) of 1.11 (95% confidence interval [1.08, 1.14]) was observed for vitamin E at a dose of 100 IU/kg body weight administered within 15 min after irradiation. Combination studies with the phosphorothioate WR-3689 (S-2([3-methylaminopropyl]amino)ethylphosphorothioic acid) were undertaken to determine whether radioprotection by WR-3689 could be enhanced by vitamin E. Mice were given WR-3689 (150-225 mg/kg, intraperitoneally) 30 min before irradiation and were given vitamin E (100 IU/kg) either 1 hr before or within 15 min after irradiation. Survival was significantly increased in mice given vitamin E and WR-3689 before irradiation as compared to mice given WR-3689 alone: the DRF for WR-3689 (150 mg) was 1.35 [1.32, 1.38]; for WR-3689 combined with vitamin E (100 IU), the DRF was 1.49 [1.45, 1.53].
Srinivasan
V
V
Radiation Biochemistry Department, Armed Forces Radiobiology Research Institute, Bethesda, MD 20889-5145.
Weiss
J F
JF
D004999:Amifostine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000818:Animals; D007279:Injections, Subcutaneous; D008297:Male; D051379:Mice; D011833:Radiation Injuries, Experimental / Q000401:mortality*; D011837:Radiation-Protective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D015996:Survival Rate; D014810:Vitamin E / Q000008:administration & dosage / Q000627:therapeutic use*
D011837:Radiation-Protective Agents; D014810:Vitamin E; C049344:S-2-(3-methylaminopropylamino)ethylphosphorothioic acid; D004999:Amifostine