Caffeine protects mice against whole-body lethal dose of gamma-irradiation.
Administration of caffeine (1,3,7-trimethylxanthine), a major component of coffee, to Swiss mice at doses of 80 or 100 mg/kg body weight 60 min prior to whole-body lethal dose of gamma-irradiation (7.5 Gy) resulted in the survival of 70 and 63% of animals, respectively, at the above doses in contrast to absolutely no survivors (LD-100/25 days) in the group exposed to radiation alone. Pre-treatment with a lower concentration of caffeine (50 mg/kg) did not confer any radioprotection. The protection exerted by caffeine (80 mg/kg), however, was reduced from 70 to 50% if administered 30 min prior to irradiation. The trend statistics reveal that a dose of 80 mg/kg administered 60 min before whole-body exposure to 7.5 Gy is optimal for maximal radioprotection. However, caffeine (80 mg/kg) administered within 3 min after irradiation offered no protection. While there is documentation in the literature that caffeine is an antioxidant and radioprotector against the oxic pathway of radiation damage in a wide range of cells and organisms, this is the first report demonstrating unequivocally its potent radioprotective action in terms of survival of lethally whole-body irradiated mice.
George
K C
KC
Biosciences Group, Bhabha Atomic Research Centre, Trombay, Mumbai, India.
Hebbar
S A
SA
Kale
S P
SP
Kesavan
P C
PC
D000818:Animals; D002110:Caffeine / Q000008:administration & dosage / Q000494:pharmacology*; D016009:Chi-Square Distribution; D005260:Female; D005720:Gamma Rays; D051379:Mice; D011833:Radiation Injuries, Experimental / Q000401:mortality / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors; D014916:Whole-Body Irradiation
D011837:Radiation-Protective Agents; D002110:Caffeine