OBJECTIVE: To clarify the genotoxicity induced by acute exposure of ozone with different concentrations on pulmonary cells in rats. METHODS: Thirty-six Wistar rats were randomly divided into control group (filtered air exposure) and ozone exposure group (0.12 ppm, 0.5 ppm, 1.0 ppm, 2.0 ppm, 4.0 ppm) with 6 in each group. After rats were exposed to different concentrations of ozone for 4 h, lung tissues were taken and single cells were isolated. Then, 8-hydroxydeoxyguanosine (8-OHdG) was quantitatively detected by enzyme-linked immunosorbent assay. Comet assay, micronucleus test and DNA- protein cross-linking assay were used to analyze DNA and chromosome damages. RESULTS: Compared with the control group, the content of 8-OHdG in lung tissue was increased significantly from the ozone exposure concentration of 0.12 ppm, reaching the highest value at 0.5 ppm. With the increase of ozone exposure concentration, the tail rate of comets was increased gradually, and there was a significant dose-effect relationship. The cross-linking rate of DNA- protein was increased first and then was decreased with a maximum value at 2.0 ppm group. Although the micronucleus rate of lung cells showed an upward trend, there was no significant difference compared with the control group. CONCLUSION Acute exposure of ozone at low concentrations (0.12 ppm) could lead to DNA damage in the pulmonary cells of rats, while no significant chromosome damage was found even in the group with ozone concentration reached to 4 ppm.
Animals ; Comet Assay ; DNA Damage ; Lung ; cytology ; pathology ; Micronucleus Tests ; Ozone ; adverse effects ; Random Allocation ; Rats ; Rats, Wistar

Among three representative species of Angelica found in Asian countries, including Korea, China, and Japan, Angelica acutiloba (AA) has been used as traditional herbal medicine with antitumor, anti-inflammatory, anti-obesity, and anti-diabetes activities. In this study, the potential genotoxicity and mutagenicity of the AA extract were examined in a battery of in vitro and in vivo tests (bacterial reverse mutation assay, in vitro chromosomal aberrations assay, and in vivo micronucleus assay) in accordance with the test guidelines for toxicity testing developed by the Organization for Economic Cooperation and Development. Upon testing in the bacterial mutation assay (Ames test) using five Salmonella typhimurium TA98, TA100, TA102, TA1535 and TA1537, no significant increase the number of revertant colonies in the metabolic activation system and non-activation system was noted in the AA extract groups. Also, in the chromosome aberration test, the AA extract did not cause chromosomal aberration with or without metabolic activation by S9 mix. A bone marrow micronucleus test of mice demonstrated that the incidence of micronucleated polychromatic erythrocytes in the AA extract groups (500, 1000 and 2000 mg/kg BW) was equivalent to that of the negative control group. Based on these results from a standard battery of assays, the AA extract was concluded to have no genotoxic at the proper dose.
Activation, Metabolic ; Angelica* ; Animals ; Asian Continental Ancestry Group ; Bone Marrow ; China ; Chromosome Aberrations ; Erythrocytes ; Herbal Medicine ; Humans ; In Vitro Techniques* ; Incidence ; Japan ; Korea ; Medicine, Traditional ; Mice ; Micronucleus Tests ; Organisation for Economic Co-Operation and Development ; Salmonella typhimurium ; Toxicity Tests

We evaluated the antimutagenic effects of 10 kinds of bioactive phytochemicals and some phytochemical combinations against methotrexate (MTX)-induced genotoxicity by the umu test in Salmonella typhimurium TA1535/pSK1002 combined with a micronucleus assay. We observed that allicin, proanthocyanidins, polyphenols, eleutherosides, and isoflavones had higher antimutagenic activities than the other five types of bioactive phytochemicals. At the highest dose tested, MTX-induced genotoxicity was inhibited by 25%-75%. Kunming mice treated by MTX along with bioactive phytochemical combinations showed significant reduction in micronucleus induction and sperm abnormality rate (P<0.01). These results indicate that bioactive phytochemical combinations can be potentially used as new cytoprotectors.
Animals ; Antimetabolites, Antineoplastic ; adverse effects ; Cytoprotection ; Drug Evaluation, Preclinical ; Female ; Male ; Methotrexate ; adverse effects ; Mice ; Micronucleus Tests ; Phytotherapy ; Plant Extracts ; Random Allocation ; Salmonella typhimurium

OBJECTIVETo investigate whether inhalable particulate matters can cause the damage of chromosome or mitotic apparatus to produce micronucleus, and to evaluate genetic toxicology of moxa smoke on chromosome.

METHODSBy MTT method, the 24 h half maximal inhibitory concentration (IC50) of moxa smoke condensation (MSC) on Chinese hamster ovary (CHO) cells was 0.087 mg/mL. CHO cells, which were cultured in vitro, were divided into a solvent control group, a positive control group (cyclophosphamide as solvent), a low concentration group, a moderate concentration group and a high concentration group. The low concentration group, moderate concentration group and high concentration group were set approximately 1/8, 1/4, 1/2 of IC50, respectively. Whether micronucleus had dose-effect response induced by the damage of chromosome or mitotic apparatus was observed after CHO cells were contaminated by MSC in the low concentration group, moderate concentration group and high concentration group.

RESULTSThe rate of micronucleus induced by MSC in the low concentration group, moderate concentration group and high concentration group was higher than that in the solvent control group (all P < 0.05), which presented dosage-effect response. The experiment was repeated 3 times, indicating it was repeatable with statistical significance.

CONCLUSIONHigh concentration of MSC shows toxicity to induce chromosome damage, which disappears at low concentration. The genetic toxicology is also dependent on concentration, and the concentration of moxa smoke is essential. In clinical treatment, it is noted to control the level of moxa smoke, while the clinical safety standard of moxa smoke concentration is in need of further study.

Air Pollutants ; adverse effects ; Animals ; CHO Cells ; Cell Nucleus ; drug effects ; genetics ; Cricetinae ; Cricetulus ; Inhalation Exposure ; adverse effects ; analysis ; Micronucleus Tests ; Moxibustion ; adverse effects ; Particulate Matter ; adverse effects ; Smoke ; adverse effects ; analysis

PURPOSE: Mefenamic acid (MEF) as a non-steroidal anti-inflammatory drug is used as a medication for relieving of pain and inflammation. Radiation-induced inflammation process is involved in DNA damage and cell death. In this study, the radioprotective effect of MEF was investigated against genotoxicity induced by ionizing radiation in human blood lymphocytes. MATERIALS AND METHODS: Peripheral blood samples were collected from human volunteers and incubated with MEF at different concentrations (5, 10, 50, or 100 microM) for two hours. The whole blood was exposed to ionizing radiation at a dose 1.5 Gy. Lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis blocked binucleated lymphocyte. RESULTS: A significant decreasing in the frequency of micronuclei was observed in human lymphocytes irradiated with MEF as compared to irradiated lymphocytes without MEF. The maximum decreasing in frequency of micronuclei was observed at 100 microM of MEF (38% decrease), providing maximal protection against ionizing radiation. CONCLUSION: The radioprotective effect of MEF is probably related to anti-inflammatory property of MEF on human lymphocytes.
Cell Death ; Cytokinesis ; DNA Damage ; Healthy Volunteers ; Humans* ; Inflammation ; Lymphocytes* ; Mefenamic Acid* ; Micronucleus Tests ; Radiation, Ionizing ; Radiation-Protective Agents

Chemical mutagenicity is a major hazard that is important to workers' health. Despite the use of large amounts of allyl chloride, the available mutagenicity data for this chemical remains controversial. To clarify the mutagenicity of allyl chloride and because a micronucleus (MN) test had not yet been conducted, we screened for MN induction by using male ICR mice bone marrow cells. The test results indicated that this chemical is not mutagenic under the test conditions. In this paper, the regulatory test battery and several assay combinations used to determine the genotoxic potential of chemicals in the workplace have been described. Further application of these assays may prove useful in future development strategies of hazard evaluations of industrial chemicals. This study also should help to improve the testing of this chemical by commonly used mutagenicity testing methods and investigations on the underlying mechanisms and could be applicable for workers' health.
Animals ; Bone Marrow Cells ; Classification* ; Humans ; Male ; Mice ; Mice, Inbred ICR ; Micronucleus Tests* ; Mutagenicity Tests* ; Occupational Diseases

OBJECTIVETo investigate the cell proliferation and genome stability in workers with occupational exposure to diesel exhaust (DE).

METHODSIn 2012, 117 DE-exposed workers and 106 control workers were recruited by cluster sampling in this study. The demographic data were obtained by questionnaire survey. The airborne fine particle and enriched polycyclic aromatic hydrocarbons (PAHs) at different workplaces were collected and analyzed. The concentrations of main PAHs monohydroxy metabolites in the urine were determined by high performance liquid chromatography-mass spectrometry (LC-MS), which could reflect the internal exposure level of DE. The cell proliferation capacity and genome stability in the periphery lymphocytes of workers were evaluated by cytokinesis-block micronucleus (CBMN) cytome assay.

RESULTSThe concentrations (median (P5-P95)) of total PAHs monohydroxy metabolites in the urine of exposed group and control group were 12.96 (4.73-28.10), 4.76 (0.90-15.00) µg/L, respectively, and the exposed group was higher than that of controls (Z = -8.77, P < 0.001). The nuclear division index (NDI) of exposed group and control group was 1.68±0.13, 1.85±0.16, respectively, and the NDI of exposed group showed significantly decreased (t = 8.86, P < 0.001), while the genome instability index calculated by micronucleus, nuclear bridges and nuclear buds, of exposed group and control group was 13.27±6.26, 4.83±3.38, respectively, and the exposed group had statistically significant increase (Z = -10.08, P < 0.001). The tertiles of total PAHs monohydroxy metabolites in the urine were categorized into low, medium and high groups (<5.96, 5.96-12.46, >12.46 µg/L). With the NDI decreased, 1.81±0.17, 1.79±0.17, 1.68±0.14 (F = 13.14, P < 0.001), genome instability index began to increase 5.80±4.15, 9.97±7.14, 11.99±6.61 (/1 000), respectively (χ(2) = 36.74, P < 0.001). With the increase of total PAHs monohydroxy metabolites level in corresponding groups. In addition, the NDI was negatively correlated with the frequencies of micronucleus, nuclear bridges, nuclear buds and genome instability index, respectively, and the difference was statistically significant (P < 0.001).

CONCLUSIONSDE exposure lead to inhibition of cell proliferation capacity and increase genome instability in the peripheral lymphocytes of occupational-exposed population, providing important clues and evidence for early biomarkers monitoring.

Biomarkers ; Cell Proliferation ; Chromatography, Liquid ; Genomic Instability ; Humans ; Lymphocytes ; Micronucleus Tests ; Occupational Exposure ; Particulate Matter ; Polycyclic Aromatic Hydrocarbons ; Surveys and Questionnaires ; Vehicle Emissions ; Workplace

The micronucleus test (MNT) can be used to detect multiple genetic end points simultaneously, including chromosome aberration, mis-repaired DNA damage, apoptosis, parts of mutation and so on, which MNT has been an important part of the study of cancer epidemiology.Here, we reviewed the progress of MNT in the field of molecular cancer epidemiology in recent years, including early detection and diagnosis of cancer, evaluation of carcinogenic substances, genetic susceptibility biomarkers, micronutrient and cohort studies.
Apoptosis ; Biomarkers ; Carcinogens ; Chromosome Aberrations ; Cohort Studies ; DNA Damage ; DNA Repair ; Early Detection of Cancer ; Genetic Predisposition to Disease ; Humans ; Micronucleus Tests ; Micronutrients ; Molecular Epidemiology ; Mutation ; Neoplasms

OBJECTIVES: Cigarette smoking is associated with carcinogenesis owing to the mutagenic and genotoxic effects of cigarette smoke. The aim of this study was to evaluate the mutagenic and genotoxic effects of Korean cigarettes using in vitro assays. METHODS: We selected 2 types of cigarettes (TL and TW) as benchmark Korean cigarettes for this study, because they represent the greatest level of nicotine and tar contents among Korean cigarettes. Mutagenic potency was expressed as the number of revertants per μg of cigarette smoke condensate (CSC) total particulate matter whereas genotoxic potency was expressed as a concentration-dependent induction factor. The CSC was prepared by the International Organization for Standardization 3308 smoking method. CHO-K1 cells were used in vitro micronucleus (MNvit) and comet assays. Two strains of Salmonella typhimurium (Salmonella enterica subsp.enterica; TA98 and TA1537) were employed in Ames tests. RESULTS: All CSCs showed mutagenicity in the TA98 and TA1537 strains. In addition, DNA damage and micronuclei formation were observed in the comet and MNvit assays owing to CSC exposure. The CSC from the 3R4F Kentucky reference (3R4F) cigarette produced the most severe mutagenic and genotoxic potencies, followed by the CSC from the TL cigarette, whereas the CSC from the TW cigarette produced the least severe mutagenic and genotoxic potencies. CONCLUSIONS: The results of this study suggest that the mutagenic and genotoxic potencies of the TL and TW cigarettes were weaker than those of the 3R4F cigarette. Further study on standardized concepts of toxic equivalents for cigarettes needs to be conducted for more extensive use of in vitro tests.
Benchmarking ; Carcinogenesis ; Comet Assay ; DNA Damage ; In Vitro Techniques ; Kentucky ; Methods ; Micronucleus Tests ; Nicotine ; Particulate Matter ; Salmonella typhimurium ; Smoke* ; Smoking ; Tobacco Products*

OBJECTIVES: Cigarette smoking is associated with carcinogenesis owing to the mutagenic and genotoxic effects of cigarette smoke. The aim of this study was to evaluate the mutagenic and genotoxic effects of Korean cigarettes using in vitro assays. METHODS: We selected 2 types of cigarettes (TL and TW) as benchmark Korean cigarettes for this study, because they represent the greatest level of nicotine and tar contents among Korean cigarettes. Mutagenic potency was expressed as the number of revertants per μg of cigarette smoke condensate (CSC) total particulate matter whereas genotoxic potency was expressed as a concentration-dependent induction factor. The CSC was prepared by the International Organization for Standardization 3308 smoking method. CHO-K1 cells were used in vitro micronucleus (MNvit) and comet assays. Two strains of Salmonella typhimurium (Salmonella enterica subsp.enterica; TA98 and TA1537) were employed in Ames tests. RESULTS: All CSCs showed mutagenicity in the TA98 and TA1537 strains. In addition, DNA damage and micronuclei formation were observed in the comet and MNvit assays owing to CSC exposure. The CSC from the 3R4F Kentucky reference (3R4F) cigarette produced the most severe mutagenic and genotoxic potencies, followed by the CSC from the TL cigarette, whereas the CSC from the TW cigarette produced the least severe mutagenic and genotoxic potencies. CONCLUSIONS: The results of this study suggest that the mutagenic and genotoxic potencies of the TL and TW cigarettes were weaker than those of the 3R4F cigarette. Further study on standardized concepts of toxic equivalents for cigarettes needs to be conducted for more extensive use of in vitro tests.
Benchmarking ; Carcinogenesis ; Comet Assay ; DNA Damage ; In Vitro Techniques ; Kentucky ; Methods ; Micronucleus Tests ; Nicotine ; Particulate Matter ; Salmonella typhimurium ; Smoke* ; Smoking ; Tobacco Products*