"NR8985"
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Using the Ames bacterial mutagenicity test, the comet assay, and an in vivo micronucleus test, we investigated the effect of the chemoprotective substance phenethyl isothiocyanate (PEITC) on the mutagenic activity of indirect-acting mutagens and carcinogens aflatoxin B1 (AFB1) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), and direct-acting mutagen and carcinogen N-nitroso-N-methylurea (MNU). In the Ames test, the antimutagenic activity of PEITC was studied in the concentration range 0.3–300 µg/plate. PEITC at concentrations of 0.3, 3 and 30 µg/plate reduced dose-dependently mutagenicity of AFB1 and IQ in both S.typhimurium TA98 and TA100 strains. In the case of the direct mutagen MNU, the antimutagenic effect of PEITC was detected only at concentration of 30 µg/plate in the strain TA100. The PEITC concentration 300 µg/plate was toxic in the Ames test. The 24 h pre-treatment of HepG2 cells with PEITC at concentration 0.15 µg/ml resulted in a significant decrease of DNA breaks induced by MNU at concentrations 0.25 and 0.5 mM. Although a trend towards reduced strand break level were determined also at PEITC concentrations 0.035 and 0.07 µg/ml it did not reach the statistical significance. No effect, however, of PEITC on IQ-induced DNA breaks was observed. Chemopreventive effect of PEITC was revealed also in vivo. Pretreatment of mice with PEITC concentrations of 25 and 12.5 mg/kg b.w. administered to mice in three daily doses resulted in reduction of micronucleus formation in mice exposed to all three mutagens under study, with statistically significant effect at concentration of 25 mg/kg. Results of this study indicate that the strong PEITC antimutagenic properties may have an important role in the prevention of carcinogenesis and other chronic degenerative diseases that share some common pathogenetic mechanisms.
- MeSH
- aflatoxin B1 toxicita MeSH
- antimutagenní látky aplikace a dávkování farmakologie MeSH
- chinoliny toxicita MeSH
- financování organizované MeSH
- isothiokyanatany aplikace a dávkování farmakologie MeSH
- karcinogeny toxicita MeSH
- kultivované buňky MeSH
- lidé MeSH
- methylnitrosomočovina toxicita MeSH
- mutageny toxicita MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- Salmonella typhimurium MeSH
- testy genotoxicity MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
12 il.
Green tea is the second-most consumed beverage in the world (water is the first one) and has been used medicinally for centuries in India and China. The active substances in the green tea are polyphenols (catechins) and flavonols which possess a potent antioxidant activity. Epigallocatechin gallate (EGCG) is one of the four major green tea catechins. Using the Ames test, micronucleus test, comet assay, chemiluminescence test, and blastic transformation test, we examined the antimutagenic effects of chemoprotective substance epigallocatechin gallate (EGCG) in the pure form on the mutagenicity induced by three reference mutagens: aflatoxin B1 (AFB1), 2-amino-3-methylimidazo [4,5-f] qui-noline (IQ), and N-nitroso-N-methylurea (MNU), and the effect of EGCG on the immunosuppression caused by these mutagens. Using the Ames test the dose dependent antimutagenic activity of EGCG was proved against indirect mutagens AFB1 and IQ, but not against the direct mutagen MNU. In the micronucleus test, EGCG had antimutagenic effect upon all three mutagens. EGCG decreased the level of DNA breaks induced by AFB1 in bone marrow cells and colon epithelium, and the level of DNA breaks induced by MNU in colon cells to the level found in control. The reparatory effect of EGCG on immunosupression induced by all three carcinogenic compounds was proved using chemiluminescence and blastic trasformation tests.
- Klíčová slova
- zelený čaj, epigalokatechin galát,
- MeSH
- aktivace lymfocytů MeSH
- antimutagenní látky * analýza MeSH
- čaj * chemie imunologie MeSH
- katechin * analogy a deriváty analýza genetika MeSH
- kometový test MeSH
- luminiscenční měření MeSH
- myši inbrední BALB C MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
Závěrečná zpráva o řešení grantu Interní grantové agentury MZ ČR
112 l., [26] l. obr. příl., 29 l. příl. : il., tab. ; 30 cm
V projektu bude sledována antimutagenní aktivita kombinací látek rostlinného původu v nízkých, opakovaných dávkách, vůči referenčním karcinogenům pomocí Amesova testu, mikronukleus testu a testu SSB DNA.; Anti-mutagenic activity of combinations of phytochemicals in very low doses against reference carcinogens will be investigated: in vitro, using the Ames and test SSB DNA, in vivo, using micronucleus test and test SSB DNA.
- MeSH
- antimutagenní látky MeSH
- chemoprofylaxe metody MeSH
- isothiokyanatany terapeutické užití MeSH
- katechin terapeutické užití MeSH
- kurkumin terapeutické užití MeSH
- kyselina ellagová terapeutické užití MeSH
- přijímání potravy imunologie MeSH
- testy genotoxicity MeSH
- Konspekt
- Biochemie. Molekulární biologie. Biofyzika
- NLK Obory
- biochemie
- biologie
- farmacie a farmakologie
- NLK Publikační typ
- závěrečné zprávy o řešení grantu IGA MZ ČR
