Inhibitory effect of tannins on direct-acting mutagens.

Okuda, Takuo; Mori, Kazuko; Hayatsu, Hikoya

doi:10.1248/cpb.32.3755

Cited by 132 publications

(61 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9 The mechanism of action of the antitumor effect of catechins has not been fully elucidated, but these compounds have shown a remarkable ability to oppose the activation of mutagens and carcinogens. 4,[10][11][12] Yoshizawa et al 13 have found that topical application of (-)-EGCG on mouse skin immediately blocks the specific binding of [ 3 H]-13-Otetradecanoyphorbol-13-acetate as well as that of [ 3 H]-okadaic acid in particulate skin fractions. The same study SHP, simple hyperplasia; PN, papillary or nodular hyperplasia; TP, transitional papilloma; TCC, transitional cell carcinoma; SCC, squamous cell carcinoma.…”

Section: Discussionmentioning

confidence: 99%

Inhibition of urinary bladder tumors induced by N‐butyl‐N‐(4‐hydroxybutyl)‐nitrosamine in rats by green tea

Sato

1999

Int J of Urology

View full text Add to dashboard Cite

Background: Recently, the anticarcinogenic effects of green tea have been studied in sites other than the urinary tract. The present study examined the inhibition by green tea of vesical tumors induced in rats by Nbutyl-N-(4-hydroxybutyl) nitrosamine (BBN). Methods:In the first series of experiments, 0.05% BBN was added to the drinking water of rats and remained present for 5 weeks. In one experiment, six groups of animals received either tap water, green tea, matcha, hojicha, oolong tea or black tea from week 6. In a second experiment, three groups of rats received either tap water, green tea extract or powdered green tea mixed into a pellet diet from week 6. In a third experiment, five groups of rats were fed a pellet diet with addition of either 0, 0.15, 1.5 or 3.0% powdered green tea from week 6. All rats were killed and examined at 40 weeks. Results: Green tea, particularly green tea leaves, dose-dependently inhibited the growth of BBN-induced urinary bladder tumors when given after the carcinogen. Conclusions: Green tea may inhibit bladder tumor growth.

show abstract

Section: Discussionmentioning

confidence: 99%

Inhibition of urinary bladder tumors induced by N‐butyl‐N‐(4‐hydroxybutyl)‐nitrosamine in rats by green tea

Sato

1999

Int J of Urology

View full text Add to dashboard Cite

show abstract

“…From a nutritional point of view, high tannins diets consumption leads to different episodes in humans and animals. Scientific references report evident correlation between dietary polyphenols rich diets and health enhancing properties: antioxidant properties [11][12][13], antibacterial activity on different bacterial strains in vitro and in vivo [7,[14][15][16][17][18][19][20], antiparasitic [21], antiulcerogenic [22][23][24] antidiarrhoic [25], antimutagenic [26][27][28][29][30][31][32][33], antitumor [34][35][36][37][38], and some neoplastic cell line apoptosis [39,40]. On the other hand, high tannins diets might also result in detrimental effects like hepatotoxicity [41,42], toxic nephrosis [43], oesphageal cancer [44], depression of feed intake and growth rate in many animal species [45][46][47][48][49][50][51].…”

Section: Biological Role Of Polyphenolsmentioning

confidence: 99%

Dose-Response Relationship between Dietary Polyphenols from Acorns and Parotid Gland Hypertrophy in Pigs

Cappai¹,

Wolf²,

Pinna³

et al. 2012

FNS

View full text Add to dashboard Cite

Proline contents of parotid glands (PG) in pigs constantly increase after the inclusion of different amounts of ripe hulled acorns in the diet providing high polyphenols levels. The dose-response relationship was estimated on natural hydrolizable tannins (expressed as tannic acid equivalent TAE) amounts of 25.8 to 36.1 g TAE/kg DM in experimental diets. Macroscopic and histological morphometry of parotid glands greatly varied according to feed intake and dosages of TAE ingested. The PG response (hypertrophy grade) on acorns' tannins content in the diet was positively correlated (R 2 = 0.748): the response to the protein precipitating activity (PPA) of tannins consisted of a functional parotidomegaly (hypertrophy), 1.34 up to 3.55 folds than control PGs, following an oral dosage 0.596 up 1.72 TAE g·kg -1 body weight·d -1 respectively, after one week exposure.

show abstract

“…It was suggested that pyrogallol-related compounds of green tea such as EGCG, ECG and EGC are antimutagenic factors in the Escherichia coli B/R Wp2 assay system [143][144][145][146].…”

Section: A In Vivo Studiesmentioning

confidence: 99%

“…Significant inhibition activity of the tea catechins ECG and EGCG, against the mutagenicity of Trp-P-2 and N-OH-Trp-P-2 has been found by [143] using Salmonella typhimurium, TA98 and TA100 with and without rat liver S9 mix. EGCG has also an inhibitory effect against the mutagenicity of benzo[a]pyrene (B[a]P) diol epoxide in TA100 strain without S9 mix.…”

Section: A In Vivo Studiesmentioning

confidence: 99%