• Toxicological Research
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• v.29 no.4
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• pp.249-255
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• 2013

Erythritol is a sugar alcohol that is widely used as a natural sugar substitute. Thus, the safety of its usage is very important. In the present study, short-term genotoxicity assays were conducted to evaluate the potential genotoxic effects of erythritol. According to the OECD test guidelines, the maximum test dose was 5,000 ${\mu}g$/plate in bacterial reverse mutation tests, 5,000 ${\mu}g/ml$ in cell-based assays, and 5,000 mg/kg for in vivo testing. An Ames test did not reveal any positive results. No clastogenicity was observed in a chromosomal aberration test with CHL cells or an in vitro micronucleus test with L5178Y $tk^{+/-}$ cells. Erythritol induced a marginal increase of DNA damage at two high doses by 24 hr of exposure in a comet assay using L5178Y $tk^{+/-}$ cells. Additionally, in vivo micronucleus tests clearly demonstrated that oral administration of erythritol did not induce micronuclei formation of the bone marrow cells of male ICR mice. Taken together, our results indicate that erythritol is not mutagenic to bacterial cells and does not cause chromosomal damage in mammalian cells either in vitro or in vivo.

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.183-187
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• 1993

The anticlastogenic effect of galangin, flavonoid derivative, was studied in vivo micronucleus test using C57BL/6 mice. The frequencies of micronuclei induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in bone-marrow cells of C57BL/6 mice were significantly decreased by the simultaneous treatment or multiple pre-treatment of galangin. When galangin was orally administered at 0, 0.1, 1.0, or 10.0 mg/kg twice with 24 hr interval, together with intraperitoneally administered MNNG, there were suppressive effects in the tested doses. The most marked suppressive effect was observed in the treatment group of 1.0 mg/kg (64.5%), not in the treatment group of 10.0 mg/kg (36.3%). When galangin was multiply administered at 1/7 or 1 mg/kg for 7 days respectively, galangin showed higher suppressive effect in the treatment group of 1/7 mg/kg (23.5%) rather than in the treatment group of 1 mg/kg (13.5%). In another experiment, galangin was administered at 0.001, 0.01 or 0.1 mg/kg for 1 month respectively. The suppressive effects in one month treatment gradually increased with dose-dependent manner, although suppressive effects were not high. The results showed that galangin was effective in suppressing the frequencies of micronuclei induced by MNNG. Our study indicates that galangin is a potent anticlastogenic agent against MNNG.

• Journal of Radiation Protection and Research
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• v.24 no.4
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• pp.225-230
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• 1999

This study was carried out to investigate the radiation dose-response of micronucleus frequencies in Tradescantia pollen mother cells. The number of micronuclei increased in the tetrads as a result of chromosome deletion after irradiation. The maximal frequency of micronuclei showed a good dose-response relationship in the range of dose $0{\sim}50$ cGy. On the basis of the relationship, a dose of 1 cGy results maximally in two additional micronuclei in 100 tetrads. The radiation dose-response relationship of micronucleus occurrence is prerequisite to biological monitoring of radiations. The micronucleus assay can be applied to biological risk assessment of environmental toxicants, and to integrity test of water or soils of interest.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.355-359
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• 2019

In vivo micronucleus tests were performed to investigate the mutagenic potential of 4-butylaniline and N-butylaniline, which are used in dye intermediates and organic intermediates respectively. Groups of 5 male ICR mice were treated with vehicle or 4-butylaniline for 2 consecutive days by oral gavage at concentrations of 0 (control), 64, 160, 400, and 1000 mg/kg. Statistically significant and dose-dependent increases were found for micronuclei frequencies in male mice (p <0.05). These results suggest that 4-butylaniline can induce genetic effects in the micronuclei of male mouse bone marrow cells. Based on the positive results obtained in cytogenetic analyses of somatic cells in vivo, Globally Harmonized System of Classification and Labelling of Chemicals Category 2 was assigned. N-butylaniline was administered for 2 consecutive days by oral gavage to male ICR mice at dose of 0 (control), 64, 160, 400, and 800 mg/kg. N-butylaniline tested negative for micronuclei induction in mice, although N-butylaniline was associated with micronucleus induction at the highest dose. Based on the negative results obtained for cytogenetic analyses of somatic cells in vivo, "Not Classified" was assigned.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.333-338
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• 2003

Cytogenetic and hematological analysis was performed in bovine peripheral blood from the regions around Wolsong nuclear power plant and control area. The frequency of micronuclei (MN) in peripheral blood lymphocytes from cattle was used as a biomarker of radiobiological effects resulting from exposure to environmental radiation. An estimated dare of radiation was calculated by a best fitting linear-quadratic model based on the radiation-induced MN formation from the bovine lymphocytes exposed in vitro to radiation over the range from 0 Gy to 4 Gy. MN rates in lymphocytes of cattle from Wolsong nuclear power plant and control area were 9.87/1,000 and 9.60/1,000, respectively. There were no significant differences in MN frequencies and hematological values in cattle between Wolsong and control area. The study indicates that the MN assay is a rapid, sensitive and accurate method that can be used to monitor a large population exposed to radiation.

• Toxicological Research
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• v.18 no.4
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• pp.369-374
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• 2002

The present study was performed to validate an automated image analysis system (Loats Automated Micronucleus Scoring System) for the mouse bone marrow micronucleus assay, comparing with conventional microscopic scoring. Two studies were conducted to provide slides for a comparison of micro-nucleated polychromatic erythrocytes (MNPCEs) values collected manually to those collected by the auto-mated system. Test article A was used as an example of a compound negative for the induction of micronuclei and test article B was wed as a micronucleus-inducing agent to elicit a positive response. Cyclophosphamide was included to provide an positive control in two studies. Bone marrow samples were collected 24 h after administration of test article A and B in male ICR mice. The cells were fixed with absolute methanol and stained with May-Grunwald and Giemsa. The number of MNPCEs was determined by the analysis of 1000 total PCEs per bone marrow sample. In addition to micronucleus scoring, an index of bone marrow toxicity based on PCE ratio (% of PCEs to total erythrocytes) was determined for each sample. The automated and manual scoring was similar when the MNPCEs incidence induced by each test article was less than 10. However manual scoring was able to effectively enumerate micronucleated PCEs in mouse bone marrow when MNPCEs incidence was more than 10, such as cyclophosphamide treatment. Conversely, PCE ratio was superior in computer-assisted image analysis. Taken together, it is suggested that improvement of the automated image analysis may be necessary to render the automatic scoring as sensitive as manual scoring for routine counting of micronuclei, especially because it is superior in objectivity and high throughput scoring.

• Environmental Mutagens and Carcinogens
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• v.19 no.2
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• pp.102-107
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• 1999

A population monitoring studies for assessing the genotoxicity of occupationally exposed mixed organic solvents to printers were performed by using the chromosome aberration assay and the cytokinesis-blocked micronucleus assay. The incidence of chromosome aberrations and micronuclei was studied in the peripheral blood lymphocytes of 51 male printers and their matched controls in Seoul area. Smoking habits and duration of employment were taken into account. The frequencies of micronucleus in peripheral lymphocytes of printers were significantly different in comparision with control subjects. Also there were significant increase in the frequencies of micronucleus by duration of exposure. The frequencies of chromosome aberrations showed no significant differences between printers and their matched controls.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.182-187
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• 1995

The clastogenecity and mutagenicity of antifungal 6-[(N-halophenyl)amino]-7-chloro-5, 8-quinolinedione (RCK 3, 7, 13, 14, and 15) had been evaluated. Salmonella typhimurium reversion assay (Ames test) was used to test the mutagenicity of RCKs. RCK14 was mutagenic in S. typhimurium(TA98 and TA100) with and without rat liver microsomal activation. Whereas RCK3, 7, 13 and 15 were negative in Ames test with Salmonella typhimurium(TA98 and TA100), The clastogenecity was tested on the RCKs with in vivo mouse micronucleus assay. All of RCKs tested did not show any clastogenic effect in mouse peripheral blood. Thus RCKs were not supposed to cause any chromosomal damage termed micronuclei. These results indicate that RCK 3, 7, 13 and 15 have no genotoxic potential under these experimental condition.

• Toxicological Research
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• v.24 no.4
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• pp.321-328
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• 2008

Smoke flavors based on the thermal decomposition of wood have been applied to a variety of food products as an alternative for traditional smoking. Despite its increasing use, the available genotoxicity data on wood smoke flavors (WSF) are still controversial. Thus, potential genotoxic effects of WSF in four short-term in vitro genotoxicity assays were investigated, which included the Ames assay, chromosomal aberration assay, micronucleus test and the alkaline comet assay. WSF did not cause any mutation in the Ames assay using five tester strains at six concentrations of 0.16, 0.31, 0.63, 1.25, 2.5 and 5 ${\mu}l/plate$. To assess clastogenic effect, the in vitro chromosomal aberration assay was performed using Chinese hamster lung cells. No statistically significant increase in the number of metaphases with structural aberrations was observed at the concentrations of 1.25, 2.5, and 5 ${\mu}l/ml$. The in vitro comet assay and micronucleus test results obtained on L5178Y cells also revealed that WSF has no genotoxicity potential, although there was a marginal increase in micronuclei frequencies and DNA damage in the respective micronucleus and comet assays. Taken together, based on the results obtained from these four in vitro studies, it is concluded that WSF is not a mutagenic agent in bacterial cells and causes no chromosomal and DNA damage in mammalian cells in vitro.

• Journal of Radiation Protection and Research
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• v.20 no.2
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• pp.97-102
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• 1995

Adaptive response induced by low dose ${\gamma}-ray$ irradiation in human peripheral lymphocytes was examimed. Human lymphocytes were exposured to low dose of ${\gamma}-ray$ (priming dose, 0.01Gy) followed by high dose (challenging dose, 1.5Gy) after various time intervals (4, 7, 20 hours). Frequencies of micronuclei were enumerated in both primed and unprimed groups. Maximum reduction in frequency of micronuclei was observed when challenging dose irradiation was followed by priming dose after 4hr incubation period. When challenging doses were irradiated 7 or 20hr after priming dose, frequencies of micronuclei were reduced slighty. However, these reduction were not statistically significant. In this study, human peripheral lymphocytes were irradiated at Go phase and they showed adaptive response induced by low dose radiation. Since micronucleus assay is relatively simpler and faster than other methods, it may be a good tool for evaluating radiation-induced adaptive responses.