Search results for "Micronucleus Tests"
showing 10 items of 26 documents
Expression of xenobiotic-metabolizing enzymes in propagatable cell cultures and induction of micronuclei by 13 compounds
1990
Activities of various xenobiotic-metabolizing enzymes were determined in 18 cell lines. Activities of cytochrome P450 reductase, microsomal epoxide hydrolase and glutathione transferase were detectable in all lines. The highest values were similar to the activities found in freshly isolated rat hepatocytes. Catalase activity was also present in all 12 investigated cell lines. Activity of UDP-glucuronosyl transferase was high in some lines, but low or undetectable in others. Activity of cytosolic epoxide hydrolase was not measurable in most lines, and was low in the others. Metabolism of benzo[a]pyrene was observed in eight out of nine examined lines, no activity being found in V79 cells. V7…
Clastogenic and aneuploidizing effects of antiblastic busulphan revealed by kinetochore immunofluorescence in CHO cells.
1991
We utilized, in CHO cells, the cytoplasm preservation technique to evaluate the micronucleus frequency at different busulphan concentrations, and the indirect immunofluorescence technique, using sera obtained from patients with scleroderma (CREST variant), to analyze if busulphan-induced micronuclei have kinetochores. Results show that this alkylating agent is capable of causing a significant increase of micronuclei in vitro, a great part (40%) of them having CREST-positive kinetochores. These findings confirm the clastogenic effect of busulphan and reveal a considerable capability of this agent to induce aneuploidy. These results are examined taking into account the high incidence of secon…
Fjord-region diol-epoxides of benzo[c]chrysene are potent inducers of micronuclei in murine bone marrow
1994
Abstract Vicinal diol-epoxides are the best established carcinogenic metabolites of polycyclic aromatic hydrocarbons. Numerous studies have demonstrated their high genotoxic activity in various in vitro test systems. However, in vivo mutagenicity data are not available. The fjor-region diol-epoxides of benzo[ c ]chrysene combine high mutagenic activity in vitro with hydrolytic stability. They were tested for the induction of micronuclei in the bone marrow following intraperitoneal administration to NMRI mice. The anti diasteromer of the diol-epixode enhanced the frequency of micronucleated polycrhomatic erythrocytes strongly (7–19-fold above the value in untreated controls) over a very wide…
Usefulness of biomarkers as intermediate endpoints in health risks posed by occupational lead exposure
2015
The article concerns potential harmful effects of exposure to lead. Although the occurrence of severe lead poisoning has receded in several countries, occupational exposure resulting in moderate and clinically symptomatic toxicity is still common. An earlier and precise characterization of an individual response is obligatory in order to assess the possible risks for human health. Biomarkers may fill important gaps in the path from exposure to a disease. Specifically speaking, emerging (DNA double strand breaks and telomeric DNA erosion) and validated (micronuclei induction and chromosomal aberrations) biomarkers of genotoxicity seem to provide evidence for the assessment of molecular and c…
Cytotoxicity, Genotoxicity and Disturbance of Cell Cycle in HepG2 Cells Exposed to OTA and BEA: Single and Combined Actions
2019
Mycotoxins are produced by a number of fungal genera spp., for example, Aspergillus, Penicillium, Alternaria, Fusarium, and Claviceps. Beauvericin (BEA) and Ochratoxin A (OTA) are present in various cereal crops and processed grains. This goal of this study was to determine their combination effect in HepG2 cells, presented for the first time. In this study, the type of interaction among BEA and OTA through an isobologram method, cell cycle disturbance by flow cytometry, and genotoxic potential by in vitro micronucleus (MN) assay following the TG 487 (OECD, 2016) of BEA and OTA individually and combined in HepG2 cells are presented. Cytotoxic concentration ranges studied by the MTT assay ov…
Genotoxic and endocrine activities of bis(hydroxyphenyl)methane (bisphenol F) and its derivatives in the HepG2 cell line
2008
International audience; Human can be exposed to bis(hydroxyphenyl)methane (bisphenol F or BPF) and its derivatives as environment and food's contaminants. This study was investigated to identify and to compare toxic potency of BPF, BFDGE, and two of BPF metabolites using in vitro methods. BPF did not induce any genic mutation in bacteria when the Ames test was performed according to the OECD guideline. In contrast, using Human cell lines and Comet assay, we demonstrated that BPF and Bisphenol F Diglycidyl Ether (BFDGE) were effective on HepG2 cell DNA fragmentation at non-cytotoxic concentrations. DHB was also positive but at higher concentrations, near its limit of solubility. Neither BPF,…
Squaraine Dyes for Photodynamic Therapy: Study of Their Cytotoxicity and Genotoxicity in Bacteria and Mammalian Cells¶‡
2007
Halogenated squaraine dyes are characterized by long wavelength absorption (>600 nm) and high triplet yields and therefore represent new types of photosensitizers that could be useful for photodynamic therapy. We have analyzed the cytotoxicity and genotoxicity of the bromo derivative 1, the iodo derivative 2 and the corresponding nonhalogenated dye 3 in the absence and presence of visible light. At concentrations of 1-2 microM, 1 and 2 reduced the cloning efficiency of AS52 Chinese hamster ovary cells to less than 1% under conditions that were well tolerated in the dark. Similarly, the proliferation of L5178Y mouse lymphoma cells was inhibited by photoexcited 1 and 2 with high selectivity. …
Genotoxicity of selected pesticides in the mouse bone-marrow micronucleus test and in the sister-chromatid exchange test with human lymphocytes in vi…
1996
Selected pesticides (aldicarb, 1,3-dichloropropene, methidathion, parathion, triadimefon, vinclozolin) were tested for their clastogenic and aneugenic activities in the mouse bone-marrow micronucleus (MN) test in vivo and for their sister-chromatid exchange-inducing activities in human lymphocytes in vitro in the presence and absence of an exogenous metabolizing system from rat-liver S9. 1,3-Dichloropropene significantly increased the frequencies of micronucleated polychromatic erythrocytes (PCE) in bone-marrow cells of female mice from 3.3 MN/1000 PCE to 15.3 MN/1000 PCE (187 mg per kg body weight). 1,3-Dichloropropene (100 microM) induced 16.0 SCE/metaphase after 24 h of incubation as com…
Micronucleus frequencies and clonogenic cell survival in TK6 cells exposed to changing dose rates under controlled temperature conditions.
2014
In most exposure scenarios the dose rate of exposure is not constant. Despite this, very little information exists on the possible biological effects of exposing cells to radiation under the conditions of a changing dose rate. The current study highlights interesting effects following exposure under these conditions.We constructed a new exposure facility that allows exposing cells inside an incubator and used it to irradiate human lymphoblastoid TK6 cells both after a moderate (0.48 Gy) and a high (1.1 Gy) dose, where the change in dose rate was, respectively, ≈ 17-fold (2.2-37 mGy/min) and ≈ 39-fold (2.7-106 mGy/min). Clonogenic survival and micronuclei (MN) induction were the chosen endpo…
In vivo genotoxicity of selected herbicides in the mouse bone-marrow micronucleus test
1997
The herbicides alachlor, atrazine, terbuthylazine, gluphosinate-ammonium, isoproturon, pendimethaline and trifluralin were tested for genotoxicity in the mouse bone-marrow micronucleus test (MNT). Both atrazine and trifluraline caused a significant increase in the number of micronuclei at doses of 1,400 mg/kg body weight in female mice only. Alachlor, terbuthylazine, gluphosinate-ammonium, isoproturon and pendimethaline did not have any genotoxic effect in the mouse bone-marrow micronucleus test in either female or male animals.