Study of the radioprotective efficiency of combined administration of cysteine and natural antioxidants [rutin and vitamin E] in feverish irradiated rats

ABSTRACT

In the present experiments, a study of the radioprotective effects of natural antioxidants, rutin alone, vitamin E alone or each of them combined with synthetic radioprotector, cysteine, have been investigated in feverish irradiated rats. Furthermore, the oxidative stress biomarkers of the feverish whole body irradiated rats were examined. The data revealed deleterious damage of radiation exposure which was manifested as significant increase in lipid peroxidation measured as malondialdehyde [MDA]. On the other hand, the activity of plasma superoxide dismutase [SOD] and the blood level of glutathione [GSH] were reduced after irradiation. Effect of hyperthermia on oxidative stress biomarkers in rats were studied in this work and data showed that the increase in body temperature intensified lipid peroxidation processes where MDA in plasma and liver homogenate was increased, GSH level in blood and liver homogenate was also increased while plasma SOD activity was reduced. Effect of rutin alone, vitamin E alone or each of them combined with cysteine on oxidative stress biomarkers in hyperthermic irradiated rats was investigated. Results indicated that, pretreatment with vitamin E and rutin alone or combined with cysteine before the onset of hyperthermia significantly attenuated fever-induced increase in free radical formation and lipid peroxidation. Radiation exposure at acute single dose of 6.5 Gy did not change the body temperature when measured on the 3[rd] day following exposure. In order to determine any antipyretic effect of the drugs used, the body temperature of each animal was measured before induction of hyperthermia as well as 18 hours following yeast injection. Rats were treated with the tested drugs before induction of fever then exposed to whole body gamma radiation at acute single dose of 6.5 Gy and body temperature of each animal was measured 3 days after irradiation. Only rutin had an antipyretic effect in yeast-induced hyperthermia in rats