[Protective activity of different concentration of tea polyphenols and its major compound EGCG against whole body irradiation-induced injury in mice].
OBJECTIVE
To evaluate the different concentrate of tea polyphenols (TP) and its compound for irradiation-protection and investigate its mechanism.


METHODS
To 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.


RESULTS
This 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.


CONCLUSIONS
The 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.
Guo
Shaolai
S
Department of Clinical Pharmacology, PLA General Hospital, Beijing 100853, China.
Hu
Yuan
Y
Liu
Ping
P
Wang
Yuyu
Y
Guo
Daihong
D
Wang
Dongxiao
D
Liao
Hongho
H
D000818:Animals; D028241:Camellia sinensis / Q000737:chemistry*; D002392:Catechin / Q000008:administration & dosage / Q000031:analogs & derivatives*; D004195:Disease Models, Animal; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D051379:Mice; D010636:Phenols / Q000008:administration & dosage*; D010936:Plant Extracts / Q000008:administration & dosage*; D059808:Polyphenols; D011832:Radiation Injuries / Q000188:drug therapy / Q000201:enzymology / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000008:administration & dosage*; D011897:Random Allocation; D013482:Superoxide Dismutase / Q000097:blood; D014916:Whole-Body Irradiation / Q000009:adverse effects*
D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D059808:Polyphenols; D011837:Radiation-Protective Agents; D002392:Catechin; C045651:epigallocatechin gallate; D013482:Superoxide Dismutase