The radioprotective effects of green tea and its fractions in Gamma-irradiated mice

Kim, Se-ra; Lee, Hae-june; Kim, Sung-ho

Korean Journal of Veterinary Research 2003;43(4):633-639.

Se-ra Kim, Hae-june Lee, Sung-ho Kim

College of Veterinary Medicine, Chonnam National University

감마선 조사 마우스에서 녹차 및 분획의 방사선 장해 경감 효과

김세라, 이해준, 김성호

전남대학교 수의과대학

Abstract

We investigated the effect of green tea and its fractions of alcohol and polysaccharide on jejunal crypt survival, endogenous spleen colony formation, and apoptosis in jejunal crypt cells of mice irradiated with high and low dose of gamma-irradiation. Jejunal crypts were protected by pretreatment of green tea (i.p.: 50 mg/kg of body weight, at 12 and 36 hours before irradiation., p.o.: 1.25% water extract, for 7days before irradiation, p<0.01) and alcohol and polysaccharide fractions showed no significant modifying effects. Green tea and its fractions administration before irradiation (i.p. at 12 and 36hours before irradiation) resulted in an increase of the formation of endogenous spleen colony (p<0.05). The frequency of radiation-induced apoptosis in intestinal crypt cells was also reduced by pretreatment of green tea (i.p. at 12 and 36 hours before irradiation, p<0.05., p.o. for 7days before irradiation, p<0.001) and its fractions (p<0.001). These results indicated that green tea might be a useful radioprotector, especially since it is a relatively nontoxic natural product. Further studies are needed to characterize better the promotion nature of green tea and its components.

Key Words: Green tea, radiation, crypt survival, endogenous spleen colony, apoptosis