Effects of flavonol derivatives on the micronuclei formation by N-methyl-N′-nitro-N-nitrosoguanidine and the enhancement of bleomycin-induced chromosome aberration by N-methyl-N′-nitro-N-nitrosoguanidine

Anti-genotoxicity of galangin as a cancer chemopreventive agent candidate

Flavonoids are polyphenolic compounds that are present in plants. They have been shown to possess a variety of biological activities at non-toxic concentrations in organisms. Galangin, a member of the flavonol class of flavonoid, is present in high concentrations in medicinal plants (e.g. Alpinia officinarum) and propolis, a natural beehive product. Results from in vitro and in vivo studies indicate that galangin with anti-oxidative and free radical scavenging activities is capable of modulating enzyme activities and suppressing the genotoxicity of chemicals. These activities will be discussed in this review. Based on our review, galangin may be a promising candidate for cancer chemoprevention.

Antigenotoxicity of galangin against N-methyl-N-nitrosourea

Using the Ames bacterial mutagenicity test and an in vivo micronucleus test, we investigated the antigenotoxic effect of galangin against the genotoxicity of N-methyl-N-nitrosourea (MNU). In the Ames assay, galangin showed an antimutagenic effect towards MNU-induced mutagenicity of Salmonella typhimurium TA 100. In mice, galangin showed an anticlastogenic effect against MNU-induced micronuclei in polychromatic erythrocytes in the MNPCE in mouse bone marrow cells. On the other hand, galangin is neither mutagenic nor clastogenic in both assays. Results from our in vitro and in vivo studies indicate that galangin is capable of suppressing the mutagenicity and clastogenicity of MNU. Therefore, galangin may be a useful chemopreventive agent against potential long-term health effects from genotoxic environmental agents.

Anticlastogenic effects of galangin against mitomycin C-induced micronuclei in reticulocytes of mice

We investigated the suppressive effect of galangin on the induction of micronucleated reticulocytes (MNRETs) by mitomycin C (MMC) in mouse peripheral blood. When galangin was given to mice 24 h before the intraperitoneal injection of MMC (1 mg/kg), a more marked decrease in the frequency of MNRETs was observed than in mice with simultaneous and post-treatment of galangin. On the other hand, when galangin was given to mice for 7 consecutive days before MMC injection, galangin showed potent anticlastogenic effects, even at the lowest dose level of 0.1 mg/kg. Results from our in vivo studies indicate that galangin is capable of suppressing the clastogenic activity of the direct acting MMC. Together with our earlier observations, it appears that galangin is capable of protecting cells from the toxic effects of a variety of hazardous chemicals. Therefore, galangin may be an useful chemopreventive compound.