Lack of genotoxic potential of permethrin in mice evaluated by the comet assay and micronucleus test

Although the Comet assay, a procedure for quantitating DNA damage in mammalian cells, is considered sensitive, it has never been ascertained that its sensitivity is higher than the sensitivity of other genotoxicity assays in mammalian cells. To determine whether the power of the Comet assay to detect a low level of genotoxic potential is superior to those of other genotoxicity assays in mammalian cells, we compared the results of Comet assay with those of micronucleus test (MN test). WTK1 human lymphoblastoid cells were exposed to methyl nitrosourea (MNU), ethyl nitrosourea (ENU), methyl methanesulfonate (MMS), ethyl methanesulfonate (EMS), bleomycin (BLM), or UVC. In Comet assay, cells were exposed to each mutagen with (Comet assay/araC) and without (Comet assay) DNA repair inhibitors (araC and hydroxyurea). Furthermore, acellular Comet assay (acellular assay) was performed to determine how single-strand breaks (SSBs) as the initial damage contributes to DNA migration and/or to micronucleus formation. The lowest genotoxic dose (LGD), which is defined as the lowest dose at which each mutagen causes a positive response on each genotoxicity assay, was used to compare the power of the Comet assay to detect a low level of genotoxic potential and that of MN test; that is, a low LGD indicates a high power. Results are summarized as follows: (1) for all mutagens studied, LGDs were MN test ≦ Comet assay; (2) except for BLM, LGDs were Comet assay/araC ≦ MN test; (3) except for UVC and MNU, LGDs were acellular assay ≦ Comet assay/araC ≦ MN test ≦ Comet assay. The following is suggested by the present findings: (1) LGD in the Comet assay is higher than that in MN test, which suggests that the power of the MN test to detect a low level of genotoxic potential is superior to that of the Comet assay; (2) for the studied mutagens, all assays were able to detect all mutagens correctly, which suggests that the sensitivity of the Comet assay and that of the MN test were exactly identical; (3) the power of the Comet assay to detect a low level of genotoxic potential can be elevated to a level higher than that of MN test by using DNA resynthesis inhibitors, such as araC and HU.

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Antineoplastic Activity and Genotoxicity of Organic Extracts and Barbatic Acid Isolated from the Lichen Cladonia salzmannii Nyl

International Archives of Medicine ◽

10.3823/2594 ◽

2018 ◽

Vol 11 ◽

Cited By ~ 2

Author(s):

Joelma Pessoa Gonçalves ◽

Mônica Cristina Barroso Martins ◽

Maria de Lourdes Lacerda Buril ◽

Jaciana Dos Santos Aguiar ◽

Terezinha Gonçalves Da Silva ◽

...

Keyword(s):

Comet Assay ◽

Tumor Cell ◽

Cytotoxic Activity ◽

Cell Lines ◽

Micronucleus Test ◽

Antineoplastic Activity ◽

Sarcoma 180 ◽

Ether Extract ◽

Genotoxic Potential ◽

Organic Extracts

Background: Secondary metabolites are responsible for most of the biological activities of lichens. Many of these compounds exhibit significant antineoplastic activity. The aim of the present in vitro study was to evaluate the cytotoxic and genotoxic activities of organic extracts and purified barbatic acid from the lichen Cladonia salzmannii (Nyl.). Methods: The thallus of the lichen (22 g) was cleaned and dried with the solvents diethyl ether, chloroform and acetone. Organic extracts were obtained using the hot exhausted method in a Soxhlet apparatus. Barbatic acid (BAR) was purified from the ether extract (1.3 g). Chemical analysis of the organic extracts and purified BAR was performed using thin-layer chromatography. The purity of purified BAR was determined using high-performance liquid chromatography. The MTT method [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and cytokinesis-block proliferation index (CBPI) were used to determine the cytotoxic activity of the organic extracts and purified BAR. The micronucleus test and comet assay were used to determine genotoxic potential of the organic extracts and purified BAR. Dimethyl sulfoxide was used as the diluting solvent of the samples in all biological tests. Results: The IC50 results demonstrated significant cytotoxic potential of the ether extract (50 µg/mL) against cell lines NCI-H292 (IC50: 29.91 µg/mL), HEp-2 (IC50: 26.75 µg/mL) and HL-60 (IC50: 3.59 µg/mL) as well as the purified BAR (25 µg/mL) against cell lines HEp-2 (IC50: 15.79 µg/mL) and MCF-7 (IC50: 18.28 µg/mL). The CBPI demonstrated the cytotoxic activity of the purified BAR at all concentrations tested (5, 10, 20 and 40 µg/mL) and all organic extracts (50 µg/mL) against Ehrlich carcinoma cells. For sarcoma 180, only BAR purified at a concentration of 40 µg/mL and the ether and chloroform extracts (50 µg/mL) were considered cytotoxic. The micronucleus test revealed that the purified BAR at a concentration of 5 µg/mL had no genotoxic potential against either tumor cell line. Furthermore, the chloroform extract and purified BAR at a concentration of 10 µg/mL were not considered genotoxic for sarcoma 180. In the comet assay, all compounds tested induced DNA damage in both tumor lines. Conclusion: Based on the present results, organic extracts and purified barbatic acid from C. salzmannii exhibit cytotoxic and genotoxic activity against of the tumor cell lines tested.

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In vitro evaluation of the genotoxicity of CeO2 nanoparticles in human peripheral blood lymphocytes using cytokinesis-block micronucleus test, comet assay, and gamma H2AX

Toxicology and Industrial Health ◽

10.1177/0748233717753780 ◽

2018 ◽

Vol 34 (5) ◽

pp. 293-300 ◽

Cited By ~ 8

Author(s):

Serpil Könen-Adıgüzel ◽

Serap Ergene

Keyword(s):

Comet Assay ◽

Peripheral Blood ◽

Micronucleus Test ◽

Human Peripheral Blood ◽

Peripheral Blood Lymphocytes ◽

Blood Lymphocytes ◽

Human Peripheral Blood Lymphocytes ◽

Genotoxic Potential ◽

Wide Range

Engineered nanoparticles (ENPs) are used in a wide range of applications because of their unique properties. Cerium dioxide nanoparticles (CeO2 NPs) are one of the important ENPs, and they can cause negative health effects, such as genotoxicity, in humans and other living organisms. The aim of this work was to analyze the genotoxic effects of short-term (3–24 h) CeO2 NPs exposure to cultured human blood lymphocytes. Three genotoxicity systems “cytokinesis-block micronucleus test, comet assay, and gamma H2AX test” were used to show the genotoxic potential of CeO2 NPs (particle size <25 nm, concentrations: 6, 12, and 18 µg/mL). Hydrogen peroxide was selected as the positive-control genotoxic agent. Our results indicate that CeO2 NPs have genotoxic potential on human peripheral blood lymphocytes cells even at 3–24 h exposure under in vitro conditions.

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Genotoxic potential of quinolone antimicrobials in the in vitro comet assay and micronucleus test

Mutation Research/Genetic Toxicology and Environmental Mutagenesis ◽

10.1016/j.mrgentox.2005.11.003 ◽

2006 ◽

Vol 603 (2) ◽

pp. 135-144 ◽

Cited By ~ 25

Author(s):

Tadashi Itoh ◽

Kunitoshi Mitsumori ◽

Satomi Kawaguchi ◽

Yu F. Sasaki

Keyword(s):

Comet Assay ◽

Micronucleus Test ◽

Genotoxic Potential

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Comet assay evaluation of six chemicals of known genotoxic potential in rats

Mutation Research/Genetic Toxicology and Environmental Mutagenesis ◽

10.1016/j.mrgentox.2015.03.003 ◽

2015 ◽

Vol 786-788 ◽

pp. 172-181 ◽

Cited By ~ 8

Author(s):

Cheryl A. Hobbs ◽

Leslie Recio ◽

Michael Streicker ◽

Molly H. Boyle ◽

Jin Tanaka ◽

...

Keyword(s):

Comet Assay ◽

Genotoxic Potential

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DNA damage induced by coal dust, fly and bottom ash from coal combustion evaluated using the micronucleus test and comet assay in vitro

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2016.11.062 ◽

2017 ◽

Vol 324 ◽

pp. 781-788 ◽

Cited By ~ 30

Author(s):

Cristina Araujo Matzenbacher ◽

Ana Letícia Hilario Garcia ◽

Marcela Silva dos Santos ◽

Caroline Cardoso Nicolau ◽

Suziane Premoli ◽

...

Keyword(s):

Dna Damage ◽

Comet Assay ◽

Coal Combustion ◽

Micronucleus Test ◽

Coal Dust ◽

Bottom Ash

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Assessment of Cyto/Genotoxicity of Irinotecan in V79 Cells Using the Comet, Micronucleus, and Chromosome Aberration Assay

Archives of Industrial Hygiene and Toxicology ◽

10.2478/10004-1254-61-2010-1967 ◽

2010 ◽

Vol 61 (1) ◽

pp. 1-9 ◽

Cited By ~ 11

Author(s):

Vilena Kašuba ◽

Ružica Rozgaj ◽

Marija Gamulin ◽

Ivančica Trošić

Keyword(s):

Comet Assay ◽

Chromosome Aberration ◽

Topoisomerase I ◽

Micronucleus Test ◽

Statistical Significance ◽

Time Dependent ◽

V79 Cells ◽

Chromosome Aberration Assay ◽

Dependent Relation ◽

Dose Dependent

Assessment of Cyto/Genotoxicity of Irinotecan in V79 Cells Using the Comet, Micronucleus, and Chromosome Aberration AssayIrinotecan is a topoisomerase I interactive agent, widely used in the treatment of metastatic colorectal cancer. The genotoxic effects of the maximum single dose (18 μg mL-1), recommended monotherapy dose (9 μg mL-1), and recommended combined therapy dose (4.5 μg mL-1) of irinotecan were studied on V79 cells using the comet assay, chromosome aberration assay, and micronucleus test. The cells were treated with irinotecan for 2 h or 24 h. The statistical significance of the results was determined using the one-way ANOVA test and a nonparametric Mann Whitney U test. The comet assay did not show dose-dependent or time-dependent effects. The chromosome aberration analysis showed large DNA rearrangements, i.e., chromosome exchanges. Although the exposed cultures showed a significant increase in micronucleated cells in respect to control, no dose-dependent relation was established among the treated cultures. Time-dependent effect was also not observed.

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Detection of cytogenetic and DNA damage in peripheral erythrocytes of goldfish (Carassius auratus) exposed to a glyphosate formulation using the micronucleus test and the comet assay

Mutagenesis ◽

10.1093/mutage/gem012 ◽

2007 ◽

Vol 22 (4) ◽

pp. 263-268 ◽

Cited By ~ 173

Author(s):

T. Cavas ◽

S. Konen

Keyword(s):

Dna Damage ◽

Comet Assay ◽

Carassius Auratus ◽

Micronucleus Test ◽

Goldfish Carassius Auratus ◽

Glyphosate Formulation

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Persistent Increased Frequency of Genomic Instability in Women Diagnosed with Breast Cancer: Before, during, and after Treatments

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/2846819 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Márcia Fernanda Correia Jardim Paz ◽

André Luiz Pinho Sobral ◽

Jaqueline Nascimento Picada ◽

Ivana Grivicich ◽

Antonio Luiz Gomes Júnior ◽

...

Keyword(s):

Breast Cancer ◽

Dna Damage ◽

Comet Assay ◽

Peripheral Blood ◽

Micronucleus Test ◽

Cancer Control ◽

Control Group ◽

Breast Cancer Patients ◽

Buccal Cells ◽

Oncological Treatment

This study aimed to evaluate DNA damage in patients with breast cancer before treatment (background) and after chemotherapy (QT) and radiotherapy (RT) treatment using the Comet assay in peripheral blood and the micronucleus test in buccal cells. We also evaluated repair of DNA damage after the end of RT, as well as the response of patient’s cells before treatment with an oxidizing agent (H2O2; challenge assay). Fifty women with a mammographic diagnosis negative for cancer (control group) and 100 women with a diagnosis of breast cancer (followed up during the treatment) were involved in this study. The significant DNA damage was observed by increasing in the index and frequency of damage along with the increasing of the frequency of micronuclei in peripheral blood and cells of the buccal mucosa, respectively. Despite the variability of the responses of breast cancer patients, the individuals presented lesions on the DNA, detected by the Comet assay and micronucleus Test, from the diagnosis until the end of the oncological treatment and were more susceptible to oxidative stress. We can conclude that the damages were due to clastogenic and/or aneugenic effects related to the neoplasia itself and that they increased, especially after RT.

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