Jp. Kamat et al., Protection of superoxide dismutase by caffeine in rat liver mitochondria against gamma-irradiation, CURRENT SCI, 77(2), 1999, pp. 286-289
Radiation is one of the physical agents that induce oxidative stress. Expos
ure of rat liver mitochondria to high doses of Co-60 gamma-rays (45-600 Gy)
results in the loss of activity of superoxide dismutase (SOD), Presence of
caffeine, even in micromolar amounts, during exposure prevents loss of SOD
activity. Caffeine, at a concentration of 1 mM also showed protection agai
nst radiation-induced inhibition of two other mitochondrial enzymes, namely
succinate dehydrogenase and cytochrome c oxidase, The observed radioprotec
tive ability of caffeine may be due to its ability to scavenge the reactive
oxygen species generated by radiation and to inhibit radiation-induced mem
brane damage, as assessed by lipid peroxidation and protein oxidation.