TY - JOUR
T1 - Suppression of genotoxicity of carcinogens by (-)-epigallocatechin gallate
AU - Hayatsu, Hikoya
AU - Inada, Naomi
AU - Kakutani, Toshifumi
AU - Arimoto, Sakae
AU - Negishi, Tomoe
AU - Mori, Kazuko
AU - Okuda, Takuo
AU - Sakata, Isao
N1 - Funding Information:
r Presented at the First International Symposium on the Physiological and Pharmacological Effects of Camellia sinensis (Tea), March 4-6, 1991, American Health Foundation, New York City. Jointly sponsored by The Tea Council and the National Tea Association. * This work was supported by a Grant-in-Aid for Cancer Research (02151039) from the Ministry of Education, Science, and Culture, Japan. 3 Abbreviations used: EGCG, (-)-epigallocatechin gallate; Trp-P-l, 3-amino-1,4-dimethyl-SH-pyrido[4,3-blindole; Trp-P-2, 3-amino-1-methyl-5H-pyrido[4,3-blindole; Trp-P-2(NHOH), 3-hydroxyamino-1-methyl-SH-pyrido[4,3-blindole; Glu-P-l, 2-amino-6-methyldipyrido[l,2-a:3’,2’-dhmidazole; Glu-P-l(NHOH), 2-hydroxyamino-6-methyldipyrido[l,2-a:3’,2’-d]imidazole; B[a]P diol epoxide, 7,8-dihydroxy-9,lO-epoxy-7,8,9,lO-tetrahydrobenzo[a]pyrene; 4NQ0, 4-nitroquinoline-l-oxide; NDMA, N-nitrosodimethylamine; HPLC, high performance liquid chromatography.
PY - 1992/5
Y1 - 1992/5
N2 - Epidemiological evidence shows that green tea may be a factor in lowering cancer risk. We have investigated the possibility that (-)-epigallocatechin gallate (EGCG), a major polyphenol in green tea, might be an antimutagenic substance. In the Ames Salmonella test, EGCG suppressed the direct-acting mutagenicity of 3-hydroxyamino-1-methyl-5H-pyrido-[4,3-b]indole (Trp-P-2(NHOH)) and 2-hydroxyamino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole (Glu-P-1(NHOH)), the activated forms of food-derived carcinogens 3-amino-1-methyl-5H-pyrido[4,3-b]indole and 2-amino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole. EGCG was also effective in reducing the mutagenicity of Trp-P-2(NHOH) in mouse FM3A cells in culture. Furthermore, EGCG demonstrated a suppressive effect in the in vivo Drosophila mutation assays, i.e., the wing spot test, and the DNA repair test, on several carcinogens. EGCG was also effective in inhibiting DNA single-strand breaks in vitro caused by Glu-P-1(NHOH). We conclude that the mechanism of inhibition may not have resulted from direct interaction between EGCG and the mutagens, but rather from indirect interception of mutagen action by EGCG.
AB - Epidemiological evidence shows that green tea may be a factor in lowering cancer risk. We have investigated the possibility that (-)-epigallocatechin gallate (EGCG), a major polyphenol in green tea, might be an antimutagenic substance. In the Ames Salmonella test, EGCG suppressed the direct-acting mutagenicity of 3-hydroxyamino-1-methyl-5H-pyrido-[4,3-b]indole (Trp-P-2(NHOH)) and 2-hydroxyamino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole (Glu-P-1(NHOH)), the activated forms of food-derived carcinogens 3-amino-1-methyl-5H-pyrido[4,3-b]indole and 2-amino-6-methyldipyrido[1,2-a:3′,2′-d]imidazole. EGCG was also effective in reducing the mutagenicity of Trp-P-2(NHOH) in mouse FM3A cells in culture. Furthermore, EGCG demonstrated a suppressive effect in the in vivo Drosophila mutation assays, i.e., the wing spot test, and the DNA repair test, on several carcinogens. EGCG was also effective in inhibiting DNA single-strand breaks in vitro caused by Glu-P-1(NHOH). We conclude that the mechanism of inhibition may not have resulted from direct interaction between EGCG and the mutagens, but rather from indirect interception of mutagen action by EGCG.
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U2 - 10.1016/0091-7435(92)90044-I
DO - 10.1016/0091-7435(92)90044-I
M3 - Article
C2 - 1614998
AN - SCOPUS:0026634873
SN - 0091-7435
VL - 21
SP - 370
EP - 376
JO - Preventive Medicine
JF - Preventive Medicine
IS - 3
ER -
