Potent suppressive activity of pheophytin a and b from the non-polyphenolic fraction of green tea (Camellia sinensis) against tumor promotion in mouse skin.
Chlorophyll-related compounds pheophytin a and b have been recently identified as antigenotoxic substances in the non-polyphenolic fraction of green tea (Camellia sinensis), which suppressed umu C gene expression in tester bacteria induced by various genotoxins (Okai and Higashi-Okai, Cancer Lett. 118 (1997) 117-123). In the present study, the authors analyzed in vivo and in vitro effects of pheophytin a and b from the non-polyphenolic fraction of green tea on tumor promotion in mouse skin as follows. (1) When pheophytin a and b from green tea were topically applied prior to each treatment with a tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA) on BALB/c mouse skin initiated by 7,12 dimethylbenz[a]anthracene (DMBA), they caused suppression in a dose-dependent fashion against skin tumorigenesis. (2) Pheophytin a and b exhibited significant suppressions against TPA-induced inflammatory reaction, such as edema formation, in BALB/c mouse ear skin in a dose-dependent manner. (3) Pheophytin a and b from green tea showed inhibitory effects against early induction of ornithine decarboxylase (ODC) in BALB/c mouse skin fibroblasts caused by TPA. These results suggest that pheophytin a and b from the non-polyphenolic fraction have potent suppressive activities against tumor promotion in mouse skin.
Higashi-Okai
K
K
Department of Human Life Science, Osaka Kun-Ei Women's College, Set's City, Japan.
Otani
S
S
Okai
Y
Y
D016475:3T3 Cells; D015127:9,10-Dimethyl-1,2-benzanthracene / Q000494:pharmacology; D000818:Animals; D016588:Anticarcinogenic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000517:prevention & control; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000517:prevention & control*; D009955:Ornithine Decarboxylase / Q000378:metabolism; D010674:Pheophytins / Q000302:isolation & purification / Q000494:pharmacology*; D012867:Skin / Q000187:drug effects / Q000201:enzymology; D012878:Skin Neoplasms / Q000517:prevention & control*; D013662:Tea / Q000737:chemistry*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D016588:Anticarcinogenic Agents; D010674:Pheophytins; D013662:Tea; D015127:9,10-Dimethyl-1,2-benzanthracene; D009955:Ornithine Decarboxylase; D013755:Tetradecanoylphorbol Acetate