OBJECTIVETo evaluate the different concentrate of tea polyphenols (TP) and its compound for irradiation-protection and investigate its mechanism.

METHODTo evaluate the radioprotective activity, mice were exposed to whole body gamma irradiation. TP 80 and TP 50 (50, 10 mg x kg(-1)) and its major constituent epigallocatechin gallate (EGCG) (50, 10 mg x kg(-1)) were administered after irradiation to examine its inhibition against irradiation-induced injury.

RESULTThis study indicate that in comparison with non-irradiated controls, irradiation resulted in a significant reduction the spleen index (spleen weight/body weight 100), haematological parameters (RBC, WBC and PLT), activity of superoxide dismutase (SOD), and increase of malondialdehde (MDA) level in 28 days. Oral administration of TP (50 mg x kg(-1)) shown the best effect on reducing the irradiation-induced injury on mice studied, and showed a protective effect against irradiation-induced haematological parameters (RBC, WBC and PLT), the spleen index and MDA level significant reduction, and antioxidase activity (SOD) decrease.

CONCLUSIONThe results suggest that TP 50 mg x kg(-1) and EGCG have in vivo antioxidant potential and radioprotective activity against whole body gamma irradiation in mice. It may be concluded that TP (50% EGCG) possess good irradiation-protective and antioxidant effect.

Animals ; Camellia sinensis ; chemistry ; Catechin ; administration & dosage ; analogs & derivatives ; Disease Models, Animal ; Female ; Flavonoids ; administration & dosage ; Humans ; Male ; Mice ; Phenols ; administration & dosage ; Plant Extracts ; administration & dosage ; Polyphenols ; Radiation Injuries ; drug therapy ; enzymology ; prevention & control ; Radiation-Protective Agents ; administration & dosage ; Random Allocation ; Superoxide Dismutase ; blood ; Whole-Body Irradiation ; adverse effects