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Sample records for c-induced genotoxic damage

  1. Genotoxic and anti-genotoxic effects of esculin and its oligomer fractions against mitomycin C-induced DNA damages in mice.

    Science.gov (United States)

    Mokdad Bzeouich, Imen; Mustapha, Nadia; Maatouk, Mouna; Ghedira, Kamel; Ghoul, Mohamed; Chekir-Ghedira, Leila

    2016-12-01

    Mitomycin C is one of the most effective chemotherapeutic drugs against various solid tumors. However, despite its wide spectrum of clinical benefits, this agent is capable of inducing various types of genotoxicity. In this study, we investigated the effect of esculin and its oligomer fractions (E1, E2 and E3) against mitomycin C induced genotoxicity in liver and kidney cells isolated from Balb/C mice using the comet assay. Esculin and its oligomer fractions were not genotoxic at the tested doses (20 mg/kg and 40 mg/kg b.w). A significant decrease in DNA damages was observed, suggesting a protective role of esculin and its oligomer fractions against the genotoxicity induced by mitomycin C on liver and kidney cells. Moreover, esculin and its oligomer fractions did not induce an increase of malondialdehyde levels.

  2. Effect of recombinant human erythropoietin on mitomycin C-induced oxidative stress and genotoxicity in rat kidney and heart tissues.

    Science.gov (United States)

    Rjiba-Touati, K; Ayed-Boussema, I; Guedri, Y; Achour, A; Bacha, H; Abid-Essefi, S

    2016-01-01

    Mitomycin C (MMC) is an antineoplastic agent used for the treatment of several human malignancies. Nevertheless, the prolonged use of the drug may result in a serious heart and kidney injuries. Recombinant human erythropoietin (rhEPO) has recently been shown to exert an important cytoprotective effect in experimental brain injury and ischemic acute renal failure. The aim of the present work is to investigate the cardioprotective and renoprotective effects of rhEPO against MMC-induced oxidative damage and genotoxicity. Our results showed that MMC induced oxidative stress and DNA damage. rhEPO administration in any treatment conditions decreased oxidative damage induced by MMC. It reduced malondialdehyde and protein carbonyl levels. rhEPO ameliorated reduced glutathione plus oxidized glutathione modulation and the increased catalase activity after MMC treatment. Furthermore, rhEPO restored DNA damage caused by MMC. We concluded that rhEPO administration especially in pretreatment condition protected rats against MMC-induced heart and renal oxidative stress and genotoxicity.

  3. Genotoxicity and cytotoxicity evaluation of oenothein B and its protective effect against mitomycin C-induced mutagenic action.

    Science.gov (United States)

    Silva, Cinthia Aparecida; Silva, Carolina Ribeiro; Véras, Jefferson Hollanda; Chen-Chen, Lee; Ferri, Pedro Henrique; Santos, Suzana da Costa

    2014-06-01

    The natural product oenothein B (OeB), a dimeric macrocyclic ellagitannin, has a wide range of biological activities, such as antioxidant, anti-inflammatory, anti-viral, antifungal, and antitumor. However, investigations concerning its genotoxicity have not been carried out. This study assessed the cytotoxicity, genotoxicity, and protective effects of oenothein B using in vitro SOS-Inductest and in vivo mouse bone marrow micronucleus (MN) assay through oral and intraperitonial routes. In both assays oenothein B did not produce genotoxic effects in any of doses tested; in contrast, cytotoxic effect in cells was detected only in mice groups treated by both routes and exposed for 24 and 48h. Antigenotoxic and anticytotoxic activities of oenothein B were evaluated using both assays in combination with mitomycin C (MMC), a bioreductive alkylating agent. In the MN assay, a significant reduction was observed in MN frequency in all groups co-treated with MMC and OeB compared to those which received only MMC. Anticytotoxicity was observed in mice groups exposed to OeB and MMC for 24 and 48h. In the SOS-Inductest, oenothein B failed to show antigenotoxic and anticytotoxic effects; thus, it undoubtedly showed an in vivo protective activity against primary DNA damage induced by mitomycin C.

  4. Genotoxicity of refinery waste assessed by some DNA damage tests.

    Science.gov (United States)

    Gupta, Amit Kumar; Ahmad, Irshad; Ahmad, Masood

    2015-04-01

    Refinery waste effluent is well known to contain polycyclic aromatic hydrocarbons, phenols and heavy metals as potentially genotoxic substances. The aim of the present study was to assess the genotoxic potential of Mathura refinery wastewater (MRWW) by various in vitro tests including the single cell gel electrophoresis, plasmid nicking assay and S1 nuclease assay. Treatment of human lymphocytes to different MRWW concentrations (0.15×, 0.3×, 0.5× and 0.78×) caused the formation of comets of which the mean tail lengths increased proportionately and differed significantly from those of unexposed controls. The toxic effect of MRWW on DNA was also studied by plasmid nicking assay and S1 nuclease assay. Strand breaks formation in the MRWW treated pBR322 plasmid confirmed its genotoxic effect. Moreover, a dose dependent increase in cleavage of calf thymus DNA in S1 nuclease assay was also suggestive of the DNA damaging potential of MRWW. A higher level of ROS generation in the test water sample was recorded which might be contributing to its genotoxicity. Interaction between the constituents of MRWW and calf thymus DNA was also ascertained by UV-visible spectroscopy.

  5. Genotoxicity of formaldehyde: Molecular basis of DNA damage and mutation

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    Masanobu eKawanishi

    2014-09-01

    Full Text Available Formaldehyde is commonly used in the chemical industry and is present in the environment, such as vehicle emissions, some building materials, food and tobacco smoke. It also occurs as a natural product in most organisms, the sources of which include a number of metabolic processes. It causes various acute and chronic adverse effects in humans if they inhale its fumes. Among the chronic effects on human health, we summarize data on genotoxicity and carcinogenicity in this review, and we particularly focus on the molecular mechanisms involved in the formaldehyde mutagenesis. Formaldehyde mainly induces N-hydroxymethyl mono-adducts on guanine, adenine and cytosine, and N-methylene crosslinks between adjacent purines in DNA. These crosslinks are types of DNA damage potentially fatal for cell survival if they are not removed by the nucleotide excision repair pathway. In the previous studies, we showed evidence that formaldehyde causes intra-strand crosslinks between purines in DNA using a unique method (Matsuda et al. Nucleic Acids Res. 26, 1769-1774,1998. Using shuttle vector plasmids, we also showed that formaldehyde as well as acetaldehyde induces tandem base substitutions, mainly at 5’-GG and 5’-GA sequences, which would arise from the intra-strand crosslinks. These mutation features are different from those of other aldehydes such as crotonaldehyde, acrolein, glyoxal and methylglyoxal. These findings provide molecular clues to improve our understanding of the genotoxicity and carcinogenicity of formaldehyde.

  6. DNA damage in caged Gammarus fossarum amphipods: A tool for freshwater genotoxicity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Lacaze, Emilie [Universite de Lyon, INRA-ENTPE, Laboratoire des Sciences de l' Environnement, rue Maurice Audin, Vaulx en Velin F-69518 (France); Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France); Devaux, Alain [Universite de Lyon, INRA-ENTPE, Laboratoire des Sciences de l' Environnement, rue Maurice Audin, Vaulx en Velin F-69518 (France); Mons, Raphael [Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France); Bony, Sylvie [Universite de Lyon, INRA-ENTPE, Laboratoire des Sciences de l' Environnement, rue Maurice Audin, Vaulx en Velin F-69518 (France); Garric, Jeanne [Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France); Geffard, Alain [EA 2069 URVVC-SE, Laboratoire d' Eco-Toxicologie, UFR Sciences, Moulin de la Housse, BP 1039, 51687 Reims Cedex 2 (France); Geffard, Olivier, E-mail: olivier.geffard@cemagref.fr [Cemagref, Unite de Recherche des Milieux Aquatiques, (UR MALY), 3 bis quai Chauveau, 69336 Lyon, Cedex 9 (France)

    2011-06-15

    The aim of this study was to propose a tool for freshwater environmental genotoxicity assessment using Gammarus fossarum, a high ecologically relevant species. In a first part, gammarids were caged upstream and downstream wastewater treatment plant effluent output. The sensitivity of genotoxic responses of haemocytes, oocytes and spermatozoa was compared using the Comet assay. Spermatozoa appeared to be the most sensitive, suitable and relevant cell type for genotoxicity risk assessment. In a second part, a watershed-scale study was conducted over 2 years to evaluate the applicability of our caging procedure. The genotoxic impact of a contamination was followed, taking into account seasonal variability. DNA damage in spermatozoa exhibited low basal level and low variability in control upstream sites, providing a reliable discrimination of polluted sites. Finally, DNA damage in caged G. fossarum has been proved to be a sensitive and reproducible tool for freshwater genotoxicity assessment. - Highlights: > Two different contamination contexts: WWTP effluents and polymetallic contamination. > DNA damage in caged Gammarus fossarum is a sensitive tool for freshwater quality assessment. > Spermatozoa is the most relevant cell type for biomonitoring freshwater genotoxicity. > Combining biomarker responses with analytical chemistry provides rich ecotoxicological information. - We propose an approach to assess freshwater genotoxicity in the field based on caged Gammarus fossarum (Crustacea, amphipoda).

  7. The role of intracellular redox imbalance in nanomaterial induced cellular damage and genotoxicity

    DEFF Research Database (Denmark)

    Kermanizadeh, Ali; Chauché, Caroline; Brown, David M;

    2015-01-01

    as one of the main contributors to nanomaterial (NM) induced adverse effects. One of the most important and widely investigated of these effects is genotoxicity. In general, systems that defend an organism against oxidative damage to DNA are very complex and include prevention of reactive oxygen species...

  8. Genotoxic damage in pathology anatomy laboratory workers exposed to formaldehyde.

    Science.gov (United States)

    Costa, Solange; Coelho, Patrícia; Costa, Carla; Silva, Susana; Mayan, Olga; Santos, Luís Silva; Gaspar, Jorge; Teixeira, João Paulo

    2008-10-30

    Formaldehyde (FA) is a chemical traditionally used in pathology and anatomy laboratories as a tissue preservative. Several epidemiological studies of occupational exposure to FA have indicated an increased risk of nasopharyngeal cancers in industrial workers, embalmers and pathology anatomists. There is also a clear evidence of nasal squamous cell carcinomas from inhalation studies in the rat. The postulated mode of action for nasal tumours in rats was considered biologically plausible and considered likely to be relevant to humans. Based on the available data IARC, the International Agency for Research on Cancer, has recently classified FA as a human carcinogen. Although the in vitro genotoxic as well as the in vivo carcinogenic potentials of FA are well documented in mammalian cells and in rodents, evidence for genotoxic effects and carcinogenic properties in humans is insufficient and conflicting thus remains to be more documented. To evaluate the genetic effects of long-term occupational exposure to FA a group of 30 Pathological Anatomy laboratory workers was tested for a variety of biological endpoints, cytogenetic tests (micronuclei, MN; sister chromatid exchange, SCE) and comet assay. The level of exposure to FA was evaluated near the breathing zone of workers, time weighted average of exposure was calculated for each subject. The association between the biomarkers and polymorphic genes of xenobiotic metabolising and DNA repair enzymes was also assessed. The mean level of exposure was 0.44+/-0.08ppm (0.04-1.58ppm). MN frequency was significantly higher (p=0.003) in the exposed subjects (5.47+/-0.76) when compared with controls (3.27+/-0.69). SCE mean value was significantly higher (p<0.05) among the exposed group (6.13+/-0.29) compared with control group (4.49+/-0.16). Comet assay data showed a significant increase (p<0.05) of TL in FA-exposed workers (60.00+/-2.31) with respect to the control group (41.85+/-1.97). A positive correlation was found between FA

  9. Analysis of in vitro chemoprevention of genotoxic damage by phytochemicals, as single agents or as combinations.

    Science.gov (United States)

    Abraham, Suresh K; Eckhardt, Alexander; Oli, Rajaraman G; Stopper, Helga

    2012-05-15

    Cancer chemoprevention with low-dose combinations of bioactive phytochemicals instead of single agents has been suggested to induce less toxicity and improve efficacy. In this study, we selected four plant food-based phytochemicals, viz. chlorogenic acid (CLA), pelargonidin (PEL), resveratrol (RES) and epigallocatechin gallate (EGCG) to evaluate the in vitro chemoprevention of genotoxic damage in HL-60 cells. These agents were tested either individually or as a combination at two concentrations (with a 10-fold difference) against the genotoxins mitomycin C (MMC), diepoxybutane (DEB) and patulin (PAT). Our preliminary ferric reducing antioxidant power (FRAP) assay demonstrated additive effects when PEL, CLA, RES and EGCG were combined. Results of the cytokinesis-block micronucleus test showed significant protection against genotoxic damage induced by PAT, DEB and MMC when CLA, PEL, RES and EGCG were tested individually. This protective effect of the phytochemicals was not concentration-related. Both low- and high-concentration combinations of CLA, PEL, RES and EGCG showed significant reducing effects on the frequencies of micronuclei induced by PAT, DEB and MMC. However, the micronucleus test did not provide indications of additive or synergistic effects with this combination of phytochemicals. In conclusion, the chemo-preventive effects of PEL, CLA, RES and EGCG against genotoxic damage induced by MMC, DEB and PAT are indicative of a 'saturation effect' when higher concentrations and combinations of these phytochemicals are used.

  10. Anti-genotoxic ability of α-tocopherol and Anthocyanin to counteract fish DNA damage induced by musk xylene.

    Science.gov (United States)

    Rocco, Lucia; Mottola, Filomena; Santonastaso, Marianna; Saputo, Valentina; Cusano, Elena; Costagliola, Domenico; Suero, Teresa; Pacifico, Severina; Stingo, Vincenzo

    2015-11-01

    Many compounds released into the environment are able to interact with genetic material. The main purpose of genetic toxicology is to investigate the adverse effects of genotoxic molecules such as reduced fitness, changes in gene frequencies and their impact on genetic diversity in populations following genotoxic exposure. However, the ecological effects of many genotoxic compounds remain poorly understood. The aim of this research was to evaluate the genotoxic activity of an artificial musk (musk xylene, MX) and the potential anti-genotoxicity against this chemical compound of two antioxidant substances (α-tocopherol and an anthocyanins enriched extract). The studies were performed both in vivo and in vitro, using the teleost Danio rerio and the DLEC (Dicentrarchus labrax embryonic cells) cell line. We carried out the exposure to these substances at different times. DNA and cell damage and their possible repair were detected by various experimental approaches: DNA strand breaks (Comet Assay), degree of apoptosis (Diffusion Assay) and molecular alterations at the genomic level (RAPD-PCR technique). Data were collected and analyzed for statistical significance using the Student's t test. The results of this study showed that MX exhibited a genotoxic activity even after short exposure times. The anti-genotoxicity experiments evidenced that both α-tocopherol and Anthocyanin were able to contrast the genotoxic effects induced by MX, both in vivo and in vitro.

  11. Comparison of Genotoxic Damage in Monolayer Cell and Three-Dimensional Tissue-Like Cell Assemblies

    Science.gov (United States)

    Behravesh, E.; Emami, K.; Wu, H.; Gonda, S.

    Risk assessment for the biological effects of high-energy charged particles, ranging from protons to iron nuclei, encountered in space is essential for the success of long-term space exploration. While prokaryotic and eukaryotic cell models, developed in our lab and others, have advanced our understanding of many aspects of genotoxicity, there is a need for in vitro models to assess the risk to humans from space radiation insults that are representative of the cellular interactions present in tissues and capable of quantifying genotoxic damage. Toward this overall goal, the objective of this study is to examine the effect of the localized microenvironment of cells, either cultured as 2-dimensional monolayers (2D) or 3-dimensional aggregates (3D), on the rate and type of genotoxic damage, and to examine those effects after the normal cell repair processes. Rodent transgenic cell lines containing 50-70 copies of a transgene were utilized to provide the enhanced sensitivity required to enable the identification and quantification of the types of mutational events incurred from exposure to iron charged particles which makes up a significant portion of Space radiation. Although the LacI target of this system is ~1000 bps, each copy of the entire construct is over 45 kbps. The utilization of this system allows for the quantification of mutational frequency and type for the LacI target as well as assessment of DNA damage for the entire 45 kbp construct. The samples were exposed to high-LET iron charged particles at Brookhaven National Laboratory's AGS/NSRL facilities for a total dose of 0, 0.1, 0.25, 0.5, 1.0, and 2.0 Gy and recovered after 0, 1, and 7 days of tissue culture post-irradiation. The mutational frequency was found to be greater for the 3D samples when compared to the 2D samples at all doses. In addition, there was increased mutational frequency with 7 days culture post irradiation when compared to samples analyzed immediately after exposure. DNA sequencing of

  12. Genotoxic Anti-Cancer Agents and Their Relationship to DNA Damage, Mitosis, and Checkpoint Adaptation in Proliferating Cancer Cells

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    Lucy H. Swift

    2014-02-01

    Full Text Available When a human cell detects damaged DNA, it initiates the DNA damage response (DDR that permits it to repair the damage and avoid transmitting it to daughter cells. Despite this response, changes to the genome occur and some cells, such as proliferating cancer cells, are prone to genome instability. The cellular processes that lead to genomic changes after a genotoxic event are not well understood. Our research focuses on the relationship between genotoxic cancer drugs and checkpoint adaptation, which is the process of mitosis with damaged DNA. We examine the types of DNA damage induced by widely used cancer drugs and describe their effects upon proliferating cancer cells. There is evidence that cell death caused by genotoxic cancer drugs in some cases includes exiting a DNA damage cell cycle arrest and entry into mitosis. Furthermore, some cells are able to survive this process at a time when the genome is most susceptible to change or rearrangement. Checkpoint adaptation is poorly characterised in human cells; we predict that increasing our understanding of this pathway may help to understand genomic instability in cancer cells and provide insight into methods to improve the efficacy of current cancer therapies.

  13. Procyanidins from grape seeds protect against phorbol ester-induced oxidative cellular and genotoxic damage

    Institute of Scientific and Technical Information of China (English)

    Yin LU; Wan-zhou ZHAO; Zai CHANG; Wen-xing CHEN; Lin LI

    2004-01-01

    AIM: To evaluate the inhibitory effects of Vitis vinifera procyanidins (PAs) on carcinogen-induced oxidative stress.METHODS: The single cell gel electrophoresis technique (comet assay) was employed to detect DNA damage induced by the carcinogen phorbol-12-myristate-13-acetate (PMA). The release of hydrogen peroxidase from polymorphonuclear leukocytes (PMNs) was assayed by the horseradish peroxidase-mediated oxidation of phenol red. The microplate assay was used to detect the presence of oxidative products by means of 2',7'-dichlorofiuorescindiacetate (DCFH-DA). The superoxide dismutase (SOD) activity of liver mitochondria was assayed, based on the ability of SOD to inhibit the generation of superoxidate anions by the xanthine-xanthine oxidase system. The malondialdehyde (MDA) level was determined by the thiobarbimric acid (TBA) assay. RESULTS: DNA of NIH3T3 cells was significantly damaged after addition of PMA. The length of the comet tail was observed ,while in normal cells the comet tail could not be observed. PAs showed significant protective effects on carcinogen PMA-induced DNA damage. Through assessment of DCFH-DA oxidation, PAs were shown to inhibit the PMA-induced release of hydrogen peroxide by PMNs, and to inhibit respiratory burst activity in NIH3T3 mouse fibroblasts. Ex vivo study showed that serum from rats administered with PAs displayed similar effects in a dose-dependent manner. In addition, PAs suppressed liver mitochondrial lipid peroxidation induced by PMA. PAs protected the activity of SOD and decreased the level of MDA in liver mitochondria damaged by PMA. CONCLUSION: Dietary PAs from grape seeds protect against carcinogen-induced oxidative cellular and genotoxic damage.

  14. ZnO nanoparticle tracking from uptake to genotoxic damage in human colon carcinoma cells.

    Science.gov (United States)

    Condello, Maria; De Berardis, Barbara; Ammendolia, Maria Grazia; Barone, Flavia; Condello, Giancarlo; Degan, Paolo; Meschini, Stefania

    2016-09-01

    Zinc Oxide (ZnO) nanoparticles are widely used both in the industry and in biomedical applications for their chemical and physical nanomaterial properties. It is therefore essential to go in depth into the cytotoxicity mechanisms and interactions between nanomaterials and cells. The aim of this work was to evaluate the dissolution of ZnO nanoparticles and their uptake, from a few minutes after treatments up to 24h. ZnO nanoparticles routes of entry into the human colon carcinoma cells (LoVo) were followed at different times by a thorough ultrastructural investigation and semiquantitative analysis. The intracellular release of Zn(2+) ions by Zinquin fluorescent dye, and phosphorylated histone H2AX (γ-H2AX) expression were evaluated. The genotoxic potential of ZnO nanoparticles was also investigated by determining the levels of 8-hydroxyl-2'-deoxyguanosine (8-oxodG). The experimental data show that ZnO nanoparticles entered LoVo cells by either passive diffusion or endocytosis or both, depending on the agglomeration state of the nanomaterial. ZnO nanoparticles coming into contact with acid pH of lysosomes altered organelles structure, resulting in the release of Zn(2+) ions. The simultaneous presence of ZnO nanoparticles and Zn(2+) ions in the LoVo cells determined the formation of reactive oxygen species at the mitochondrial and nuclear level, inducing severe DNA damage.

  15. Follow-Up Genotoxic Study: Chromosome Damage Two and Six Years after Exposure to the Prestige Oil Spill.

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    Kristin Hildur

    Full Text Available The north-west coast of Spain was heavily contaminated by the Prestige oil spill, in 2002. Individuals who participated in the clean-up tasks showed increased chromosome damage two years after exposure. Long-term clinical implications of chromosome damage are still unknown.To realize a follow-up genotoxic study to detect whether the chromosome damage persisted six years after exposure to the oil.Follow-up study.Fishermen cooperatives in coastal villages.Local fishermen who were highly exposed (n = 52 and non-exposed (n = 23 to oil seven years after the spill.Chromosome damage in circulating lymphocytes.Chromosome damage in exposed individuals persists six years after oil exposure, with a similar incidence than those previously detected four years before. A surprising increase in chromosome damage in non-exposed individual was found six years after Prestige spill vs. those detected two years after the exposure.The sample size and the possibility of some kind of selection bias should be considered. Genotoxic results cannot be extrapolated to the approximately 300,000 individuals who participated occasionally in clean-up tasks.The persistence of chromosome damage detected in exposed individuals six years after oil exposure seems to indicate that the cells of the bone marrow are affected. A surprising increase in chromosome damage in non-exposed individuals detected in the follow-up study suggests an indirect exposition of these individuals to some oil compounds or to other toxic agents during the last four years. More long-term studies are needed to confirm the presence of chromosome damage in exposed and non-exposed fishermen due to the association between increased chromosomal damage and increased risk of cancer. Understanding and detecting chromosome damage is important for detecting cancer in its early stages. The present work is the first follow-up cytogenetic study carried out in lymphocytes to determine genotoxic damage evolution between two

  16. Development of a Fish Cell Biosensor System for Genotoxicity Detection Based on DNA Damage-Induced Trans-Activation of p21 Gene Expression

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    Huarong Guo

    2012-09-01

    Full Text Available p21CIP1/WAF1 is a p53-target gene in response to cellular DNA damage. Here we report the development of a fish cell biosensor system for high throughput genotoxicity detection of new drugs, by stably integrating two reporter plasmids of pGL3-p21-luc (human p21 promoter linked to firefly luciferase and pRL-CMV-luc (CMV promoter linked to Renilla luciferase into marine flatfish flounder gill (FG cells, referred to as p21FGLuc. Initial validation of this genotoxicity biosensor system showed that p21FGLuc cells had a wild-type p53 signaling pathway and responded positively to the challenge of both directly acting genotoxic agents (bleomycin and mitomycin C and indirectly acting genotoxic agents (cyclophosphamide with metabolic activation, but negatively to cyclophosphamide without metabolic activation and the non-genotoxic agents ethanol and D-mannitol, thus confirming a high specificity and sensitivity, fast and stable response to genotoxic agents for this easily maintained fish cell biosensor system. This system was especially useful in the genotoxicity detection of Di(2-ethylhexyl phthalate (DEHP, a rodent carcinogen, but negatively reported in most non-mammalian in vitro mutation assays, by providing a strong indication of genotoxicity for DEHP. A limitation for this biosensor system was that it might give false positive results in response to sodium butyrate and any other agents, which can trans-activate the p21 gene in a p53-independent manner.

  17. Effects of chronic exposure to benzalkonium chloride in Oncorhynchus mykiss: cholinergic neurotoxicity, oxidative stress, peroxidative damage and genotoxicity.

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    Antunes, S C; Nunes, B; Rodrigues, S; Nunes, R; Fernandes, J; Correia, A T

    2016-07-01

    Benzalkonium chloride (BAC) is one of the most used conservatives in pharmaceutical preparations. However, its use is limited to a small set of external use formulations, due to its high toxicity. Benzalkonium chloride effects are related to the potential exertion of deleterious effects, mediated via oxidative stress and through interaction with membrane enzymes, leading to cellular damage. To address the ecotoxicity of this specific compound rainbow trouts were chronically exposed to BAC at environmental relevant concentrations (ranging from 0.100 to 1.050mg/L), and the biological response of cholinergic neurotoxicity, modulation of the antioxidant defense, phase II metabolism, lipid peroxidation and genotoxicity was studied. The obtained results showed a dual pattern of antioxidant response, with significant alterations in catalase activity (starting at 0.180mg/L), and lipid peroxidation, for intermediate (0.180 and 0.324mg/L) concentrations. No significant alterations occurred for glutathione-S-transferases activity. An unexpected increased of the acetylcholinesterase activity was also recorded for the individuals exposed to higher concentrations of BAC (starting at 0.180mg/L). Furthermore, exposure to BAC resulted in the establishment of genotoxic alterations, observable (for the specific case of the comet assay results) for all tested BAC concentrations. However, and considering that the oxidative response was not devisable, other mechanisms may be involved in the genotoxic effects reported here.

  18. Protective role of taurine against genotoxic damage in mice treated with methotrexate and tamoxfine.

    Science.gov (United States)

    Alam, Sally S; Hafiz, Nagla A; Abd El-Rahim, Abeer H

    2011-01-01

    The genotoxic actions of anti-neoplastic drugs can lead to the development of secondary cancers in patients in extended remission. One of the most attractive approaches to disease prevention involves the use of natural antioxidants to protect tissue against toxic injury. We investigated the modulatory effects of exogenously administered taurine, on the genotoxicity of two well known anti-neoplastic drugs methotrexate (MTX) and tamoxifen (TAM) in Swiss albino mice. The animals were randomly divided into six groups consisting of ten mice each. Two groups were received single intraperitoneal injection of MTX (10 mg/kgb.wt.) and TAM (50 mg/kgb.wt.) to induce genotoxicity. Two other groups were treated orally with taurine (100 mg/kgb.wt.) for nine days prior to MTX and TAM administration. A vehicle treated control group and taurine control groups were also included. The protective effects of taurine were monitored by apoptosis assays and level of reduced glutathione (GSH), a key antioxidant, in liver, chromosomal aberrations in somatic and germ cells as well as sperm count, motility and morphology. The results indicated that taurine pre-treatment showed significant increment in the levels of GSH content, reduction in DNA fragmentation and ladder formation in hepatic tissue, suggesting the antioxidant activity of taurine may reduce the toxic effects of MTX and TAM. Treatment with taurine showed also significant reduction in the frequency of chromosomal aberrations in both somatic and germ cells. Moreover, it increases sperm count and motility, and decreases the incidence of sperm abnormalities. In conclusion, it appears that taurine protects against anti-neoplastic drugs-induced genotoxicity in somatic and germ tissues and may be of therapeutic potential in alleviating the risk of secondary tumors in chemotherapy.

  19. Comparison of Genotoxic Damage in Monolayer Cell Cultures and Three-Dimensional Tissue-Like Cell Assemblies

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    Behravesh, E.; Emami, K.; Wu, H.; Gonda, S.

    2004-01-01

    Assessing the biological risks associated with exposure to the high-energy charged particles encountered in space is essential for the success of long-term space exploration. Although prokaryotic and eukaryotic cell models developed in our laboratory and others have advanced our understanding of many aspects of genotoxicity, in vitro models are needed to assess the risk to humans from space radiation insults. Such models must be representative of the cellular interactions present in tissues and capable of quantifying I genotoxic damage. Toward this overall goal, the objectives of this study were to examine the effect of the localized microenvironment of cells, cultured as either 2-dimensional (2D) monolayers or 3-dimensional (3D) aggregates, on the rate and type of genotoxic damage resulting from exposure to iron charged particles, a significant portion of space radiation. We used rodent transgenic cell lines containing 50-70 copies of a LacI transgene to provide the enhanced sensitivity required to quantify mutational frequency and type in the 1,100-bp LacI target as well as assessment of DNA,damage to the entire 45-kbp construct. Cultured cells were exposed to high-enerir on charged particles at Brookhaven National Laboratory s Alternating Gradient Synchrotron facility for a total dose of 0, 0.1, 0.25,0.5, 1.0, or 2.0 Gy and allowed to recover for 0, 1, or 7 days, after which mutational type and frequency were evaluated. The mutational frequency was found to be higher in 3D samples than in 2D samples at all radiation doses. Mutational frequency also was higher at 7 days after irradiation than immediately after exposure. DNA sequencing of the mutant targets revealed that deletional mutations contributed an increasingly high percentage (up to 27%) of all mutations in cells as the dose was increased from 0.5 to 2 Gy. Several mutants also showed large and complex deletions in multiple locations within the Lac1 target. However, no differences in mutational type were

  20. Comparison of genotoxic damage in monolayer cell cultures and three-dimensional tissue-like cell assemblies

    Science.gov (United States)

    Behravesh, E.; Emami, K.; Wu, H.; Gonda, S.

    Assessing the biological risks associated with exposure to the high-energy charged particles encountered in space is essential for the success of long-term space exploration. Although prokaryotic and eukaryotic cell models developed in our laboratory and others have advanced our understanding of many aspects of genotoxicity, in vitro models are needed to assess the risk to humans from space radiation insults. Such models must be representative of the cellular interactions present in tissues and capable of quantifying genotoxic damage. Toward this overall goal, the objectives of this study were to examine the effect of the localized microenvironment of cells, cultured as either 2-dimensional (2D) monolayers or 3-dimensional (3D) aggregates, on the rate and type of genotoxic damage resulting from exposure to Fe-charged particles, a significant portion of space radiation. We used rodent transgenic cell lines containing 50-70 copies of a LacI transgene to provide the enhanced sensitivity required to quantify mutational frequency and type in the 1100-bp LacI target as well as assessment of DNA damage to the entire 45-kbp construct. Cultured cells were exposed to high-energy Fe charged particles at Brookhaven National Laboratory's Alternating Gradient Synchrotron facility for a total dose ranging from 0.1 to 2 Gy and allowed to recover for 0-7 days, after which mutational type and frequency were evaluated. The mutational frequency was found to be higher in 3D samples than in 2D samples at all radiation doses. Mutational frequency also was higher at 7 days after irradiation than immediately after exposure. DNA sequencing of the mutant targets revealed that deletional mutations contributed an increasingly high percentage (up to 27%) of all mutations in cells as the dose was increased from 0.5 to 2 Gy. Several mutants also showed large and complex deletions in multiple locations within the LacI target. However, no differences in mutational type were found between the 2D and

  1. The alkaline comet assay used in evaluation of genotoxic damage of drinking water disinfection by-products (bromoform and chloroform

    Directory of Open Access Journals (Sweden)

    Messaouda Khallef

    2015-06-01

    Full Text Available The alkaline comet assay (pH 12.3 is a useful method for monitoring genotoxic effects of environmental pollutants in the root nuclei of Allium cepa and various plants; it allows the detection of single- and double-strand breaks, incomplete excision-repair sites and cross-links. It has been introduced to detect even small changes in DNA structure. It is a technically simple, highly sensitive, fast and economic test which detects in vitro and in vivo genotoxicity (DNA integrity and packing mode in any cell types examined, and requires just a few cells for its execution (Liman et al., 2011; Yıldız et al., 2009. Chloroform and bromoform are the most important trihalomethanes found in drinking water. Different concentrations of bromoform (25, 50, 75and 100µg/ml and chloroform (25, 50, 100 and 200 µg/ml were introduced to onion tuber roots. Distilled water was used as a negative control and methyl methansulfonate (MMS-10 µg/ml as positive control. All obtained data were subjected to statistical analyses by using SPSS 15.0 for Windows software. For comparison purposes, Duncan multiple range tests using one-way analysis of variance (ANOVA were employed and p<0.05 was accepted as the test of significance. Comet assay results showed that DNA damage was significant at p <0.05 for the different concentrations of chloroform and bromoform compared to the negative control which has a damage rate equal to 3.5 ± 0.7 and the positive control which has damage rate equal to 13.5 ± 2.12. The exposure of root tip cells to these disinfection by-products increases DNA damage. All concentrations examined in this study of bromoform and chloroform cause significant harm, which could be due to DNA damage induced by oxidative stress. The measurement of DNA damage in the nuclei of higher plant tissues is a new area of study with SCGE. This assay could be incorporated into in situ monitoring of atmosphere, water and soil: the comet assay allows a fast detection without

  2. Copper-induced oxidative damage, antioxidant response and genotoxicity in Lycopersicum esculentum Mill. and Cucumis sativus L.

    Science.gov (United States)

    İşeri, Özlem Darcansoy; Körpe, Didem Aksoy; Yurtcu, Erkan; Sahin, Feride Iffet; Haberal, Mehmet

    2011-09-01

    Adequate copper (Cu(2+)) concentrations are required for plants; however, at higher concentrations it can also cause multiple toxic effects. In the present study, lipid peroxidation, hydrogen peroxide levels as well as ascorbate peroxidase (APX: EC 1/11/1/11) and catalase (CAT: EC 1.11.1.6) activities were determined in Lycopersicum esculentum Mill. and Cucumis sativus L. seedlings after 7-day exposure to copper sulfate. In addition, DNA damage in these two crops was assessed by measuring micronucleus (MN) frequency and tail moments (TM) as determined by Comet assay. Inhibitory copper concentrations (EC(50): 30 and 5.5 ppm for L. esculentum and C. sativus, respectively) were determined according to dose-dependent root inhibition curves, and EC(50) and 2×EC(50) were applied. Malondialdehyde (MDA) and H(2)O(2) levels significantly increased in all groups studied. CAT activity increased in treatment groups of C. sativus. APX activity increased in L. esculentum seedlings due to 2×EC(50) treatment. Reductions in mitotic indices (MI) represented Cu(2+)dependent root growth inhibition in all treatment groups studied. According to TMs and MN frequencies, copper exposure induced significant DNA damage (p sativus roots. In conclusion, Cu(2+)induced oxidative damage, elevations in H(2)O(2) levels and alterations in APX and CAT activities, as well as significant DNA damage in nuclei of both study groups. To our knowledge, this is the first comparative and comprehensive study demonstrating the effects of copper on two different plant species at relevant cytotoxic concentrations at both biochemical and genotoxicity levels with multiple end points.

  3. Genotoxic damage in zebra fish (Danio rerio) by arsenic in waters from Zimapan, Hidalgo, Mexico.

    Science.gov (United States)

    Ramírez, Oliveria A Baez; García, Francisco Prieto

    2005-07-01

    The induction of micronuclei in gill cells of zebra fish (Danio rerio) maintained in calcium-magnesium bicarbonated waters from a reference well and 'Zimapán 5' well, the latter with an arsenic (As) content ranging from 0.395 to 0.630 p.p.m., was studied. The specimens were studied during 180 days in three separated lots: in reference well-water (negative control), in reference water to which was added 5 mg/l As(5+) (positive control); and in water from 'Zimapán 5' well, with 65 specimens/lot. In waters an As concentration diminution was observed with time, whereas in fish there was an increase. After 30 days there was an As diminution in water from positive control of 1092.65 p.p.b. (36.42 p.p.b./day), whereas in fish it had increased to 523.81 p.p.b. (17.46 p.p.b./day). For the water from 'Zimapán 5' well, there was a diminution of 211.40 p.p.b. (7.04 p.p.b./day), and in fish there was an increase of 74.73 p.p.b. (2.49 p.p.b./day). In relation to micronucleus frequency in gill cells, at the end of 180 days in the negative control there was a spontaneous generation of 0.8 micronuclei/1000 cells, in the positive control there was a micronucleus frequency 163.5 times greater than in the negative control, whereas for the fish exposed to 'Zimapán 5' well-water the micronucleus frequency was 56.25 times greater than in the negative control. Taken together these results demonstrate the genotoxicity to Danio rerio of As in the well water.

  4. Genotoxic damage induced by isopropanol in germinal and somatic cells of Drosophila melanogaster.

    Science.gov (United States)

    Palermo, Ana María; Mudry, Marta Dolores

    2011-12-24

    Isopropanol (isopropyl alcohol, 2-propanol, IPA) is a volatile solvent widely used in domestic or industrial environments and reported as innocuous in various test systems. The aim of this work was to search for in vivo genotoxic effects of IPA in Drosophila melanogaster, studying its ability to induce nondisjunction (ND) in females, sex linked recessive lethals (SLRL) in males, and somatic mutation and/or recombination (SMART) in larvae. Treatments were acute (60min) and were administered via inhalation. IPA had low toxicity in adult flies (75% IPA mortality index, MI=12.7% (females) and 2.6% (males)) and larvae (MI=14.3%, 75% IPA). Female fertility was severely affected during the first 24h (brood I, BI) after treatment, but, afterwards, control values were recovered. IPA induced a 50-fold increase of ND (%) in 24h old females, and a six-fold rise in 4-5 d old BI offspring. Nondisjunction frequencies (%) in the offspring of broods II to V (24h in each case) were similar to control values. IPA doses of 25% and 50% (v/v), tested in 24h old females, showed a significant dose-dependent increase of ND(%)in BI only, with control values in subsequent broods. Flies gave normal offspring when kept in regular media for 24h before mating. The eye spot test (SMART) showed a significant increase at 50% IPA (p<0.05, m=2), but the response was not dose-dependent. IPA failed to induce SLRL in any of the spermatogenesis stages tested. These findings suggest that the main effect of IPA is to induce chromosomal malsegregation; IPA must be present at the resumption of M-phase I after fertilization, to exert these effects. The alcohol does not affect DNA directly, but perturbations of the nuclear membrane may be responsible for induction of ND.

  5. Genotoxicity and Cytotoxicity Evaluation of the Neolignan Analogue 2-(4-Nitrophenoxy-1Phenylethanone and its Protective Effect Against DNA Damage.

    Directory of Open Access Journals (Sweden)

    Alex Lucas Hanusch

    Full Text Available Neolignans are secondary metabolites found in various groups of Angiosperms. They belong to a class of natural compounds with great diversity of chemical structures and pharmacological activities. These compounds are formed by linking two phenylpropanoid units. Several compounds that have ability to prevent genetic damage have been isolated from plants, and can be used to prevent or delay the development of tumor cells. Genetic toxicology evaluation is widely used in risk assessment of new drugs in preclinical screening tests. In this study, we evaluated the genotoxicity and cytotoxicity of the neolignan analogue 2-(4-nitrophenoxy-1-phenylethanone (4NF and its protective effect against DNA damage using the mouse bone marrow micronucleus test and the comet assay in mouse peripheral blood. Our results showed that this neolignan analogue had no genotoxic activity and was able to reduce induced damage both in mouse bone marrow and peripheral blood. Although the neolignan analogue 4NF was cytotoxic, it reduced cyclophosphamide-induced cytotoxicity. In conclusion, it showed no genotoxic action, but exhibited cytotoxic, antigenotoxic, and anticytotoxic activities.

  6. Resistance for Genotoxic Damage in Mesenchymal Stromal Cells Is Increased by Hypoxia but Not Generally Dependent on p53-Regulated Cell Cycle Arrest

    Science.gov (United States)

    Wieduwild, Elisabeth; Nerger, Katrin; Lambrecht, Nina; Schmoll, Hans-Joachim; Müller-Tidow, Carsten; Müller, Lutz Peter

    2017-01-01

    Adult stem cells including multipotent mesenchymal stromal cells (MSC) acquire a high amount of DNA-damage due to their prolonged lifespan. MSC may exert specific mechanisms of resistance to avoid loss of functional activity. We have previously shown that resistance of MSC is associated with an induction of p53 and proliferation arrest upon genotoxic damage. Hypoxia may also contribute to resistance in MSC due to the low oxygen tension in the niche. In this study we characterized the role of p53 and contribution of hypoxia in resistance of MSC to genotoxic damage. MSC exhibited increased resistance to cisplatin induced DNA-damage. This resistance was associated with a temporary G2/M cell cycle arrest, induction of p53- and p21-expression and reduced cyclin B / cdk1-levels upon subapoptotic damage. Resistance of MSC to cisplatin was increased at hypoxic conditions i. e. oxygen <0.5%. However, upon hypoxia the cisplatin-induced cell cycle arrest and expression of p53 and p21 were abrogated. MSC with shRNA-mediated p53 knock-down showed a reduced cell cycle arrest and increased cyclin B / cdk1 expression. However, this functional p53 knock down did not alter the resistance to cisplatin. In contrast to cisplatin, functional p53-knock-down increased the resistance of MSC to etoposide. We conclude that resistance of MSC to genotoxic damage is influenced by oxygen tension but is not generally dependent on p53. Thus, p53-dependent and p53-independent mechanisms of resistance are likely to contribute to the life-long functional activity of MSC in vivo. These findings indicate that hypoxia and different resistance pathways contribute to the phenotype that enables the prolonged lifespan of MSC. PMID:28081228

  7. Internal distribution of uranium and associated genotoxic damages in the chronically exposed bivalve Corbicula fluminea

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Olivier, E-mail: olivier.simon@irsn.fr [Laboratoire de Radioecologie et Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat, 186 BP3, 13115 Saint Paul-Lez-Durance Cedex (France); Floriani, Magali; Cavalie, Isabelle; Camilleri, Virginie; Adam, Christelle; Gilbin, Rodolphe; Garnier-Laplace, Jacqueline [Laboratoire de Radioecologie et Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat, 186 BP3, 13115 Saint Paul-Lez-Durance Cedex (France)

    2011-08-15

    Uranium (U) internal distribution and involved effects in the bivalve Corbicula fluminea have been studied after direct chronic exposure (90 d, 10 {mu}g.L-1). U distribution was assessed at the subcellular level (Metal Rich Granules -MRG-, pellets and cytosol fractions) in two main organs of the bivalve (gills and visceral mass). Micro-localisation was investigated by TEM-EDX analysis in the gills epithelium. DNA damage in gill and hemolymph samples was measured by the Comet assay. The 90-d exposure period led to a significant increase of U concentration in gills over time (x5) and a large U quantity in subcellular granules in gills. Finally, a significant increase (x2) in DNA damage was noted in exposed gills and haemocytes. This study shows that the accumulation levels and consequently the potential toxicity cannot be successfully predicted only on the basis of concentration in water or in tissues and subcellular fractions after chronic exposure. - Highlights: > Relevant information concerning the chronic impact of uranium on biota is scarce. > We study its biological speciation to explain bioavailability, accumulation, toxicity. > 80% of U accumulated was measured in the pellet fraction (organelles + granules/MRG). > Chronic exposure to U induced genetic damage in gill and haemolymph cells of the bivalve.

  8. Genotoxic Evaluation of Mikania laevigata Extract on DNA Damage Caused by Acute Coal Dust Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, T.P.; Heuser, V.D.; Tavares, P.; Leffa, D.D.; da Silva, G.A.; Citadini-Zanette, V.; Romao, P.R.T.; Pinho, R.A.; Streck, E.L.; Andrade,V.M. [University of Extremo Catarinense, Criciuma, SC (Brazil)

    2009-06-15

    We report data on the possible antigenotoxic activity of Mikania laevigata extract (MLE) after acute intratracheal instillation of coal dust using the comet assay in peripheral blood, bone marrow, and liver cells and the micronucleus test in peripheral blood of Wistar rats. The animals were pretreated for 2 weeks with saline solution (groups 1 and 2) or MLE (100 mg/kg) (groups 3 and 4). On day 15, the animals were anesthetized with ketamine (80 mg/kg) and xylazine (20 mg/kg), and gross mineral coal dust (3 mg/0.3 mL saline) (groups 2 and 4) or saline solution (0.3 mL) (groups 1 and 3) was administered directly in the lung by intratracheal administration. Fifteen days after coal dust or saline instillation, the animals were sacrificed, and the femur, liver, and peripheral blood were removed. The results showed a general increase in the DNA damage values at 8 hours for all treatment groups, probably related to surgical procedures that had stressed the animals. Also, liver cells from rats treated with coal dust, pretreated or not with MLE, showed statistically higher comet assay values compared to the control group at 14 days after exposure. These results could be expected because the liver metabolizes a variety of organic compounds to more polar by-products. On the other hand, the micronucleus assay results did not show significant differences among groups. Therefore, our data do not support the antimutagenic activity of M. laevigata as a modulator of DNA damage after acute coal dust instillation.

  9. Genotoxic damage in mine workers exposed to diesel exhaust, and the effects of glutathione transferase genotypes

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Gaskell, M; Martin, E A;

    2005-01-01

    This study was performed in an Estonian shale-oil mine with the purpose to develop and apply a number of biomarkers for occupational diesel-exhaust exposure monitoring. Increased breathing-zone exposures to exhaust from operators of diesel-powered trucks in the mine was confirmed in the environme......This study was performed in an Estonian shale-oil mine with the purpose to develop and apply a number of biomarkers for occupational diesel-exhaust exposure monitoring. Increased breathing-zone exposures to exhaust from operators of diesel-powered trucks in the mine was confirmed....... The study confirms an increased level of DNA damage in workers exposed to exhaust from truck-driving in the mine. However, the results of the environmental and biological monitoring of 1-NP did not correlate, suggesting that inhalation exposure to diesel exhaust is not reflected by an increase in 1-NP......-DNA-adduct levels and/or that factors other than occupational exposure to diesel exhaust are primary determinants of these DNA-adduct levels....

  10. Modulation of Tinospora rumphii and Zinc Salt on DNA Damage in Quinoline-Induced Genotoxicity and Hepatotoxicity in Male Albino Mice

    Directory of Open Access Journals (Sweden)

    Roger Salvacion Tan

    2014-01-01

    Full Text Available Tinospora rumphii (T. rumphii is a folkloric medicinal plant that is widely distributed in Asia and Africa. It has been widely used by locals to treat many diseases including jaundice, which is a manifestation of liver damage. We investigated the action of T. rumphii crude extract together with zinc sulphate, a known tumor modulator, on hepatic injuries induced by intraperitoneal (i.p injections of quinoline on albino mice. The hepatotoxic effect was assessed by bilirubin concentration in the blood serum, while the genotoxic effect was determined by single-cell gel electrophoresis (SCGE. The mice orally fed with the crude extracts, following quinoline exposure, had reduced serum bilirubin concentration and DNA damage. Mice treated with Zinc sulphate, on the other hand, had remarkably reduced DNA damage on hepatocytes. Our findings showed that hepatoprotective potential of T. rumphii extract is dose-dependent and that utilization of the extract as medicinal remedy must be strictly monitored, while zinc was proven to reverse genotoxic effect of quinoline. This study unraveled the potential of T. rumphii extract and zinc as important hepatoprotective agents for future treatment of hepatic damage caused by chemotherapeutic agents used in cancer treatment.

  11. Translocation of human ribosomal protein S3 to sites of DNA damage is dependant on ERK-mediated phosphorylation following genotoxic stress.

    Science.gov (United States)

    Yadavilli, Sridevi; Hegde, Vijay; Deutsch, Walter A

    2007-10-01

    Besides its role in translation and ribosome maturation, human ribosomal protein S3 (hS3) is implicated in DNA damage recognition as reflected by its affinity for abasic sites and 7,8-dihydro-8-oxoguanine (8-oxoG) residues in DNA in vitro. Here, we demonstrate that hS3 is capable of carrying out both roles by its ex vivo translocation from the cytoplasm to the nucleus as a consequence of genotoxic stress. The translocation of hS3 is dependent on ERK1/2-mediated phosphorylation of a threonine residue (T42) of hS3. Two different ectopically expressed site-directed mutants of T42 failed to respond to conditions of genotoxic stress, thus providing a link between DNA damage and ERK1/2 dependent phosphorylation of hS3. Lastly, hS3 was traced in exposed cells to its co-localization with 8-oxoG foci, raising the possibility that hS3 is a member of a cellular DNA damage response pathway that results in its interaction with sites of DNA damage.

  12. In Vivo Effects of Vanadium Pentoxide and Antioxidants (Ascorbic Acid and Alpha-Tocopherol) on Apoptotic, Cytotoxic, and Genotoxic Damage in Peripheral Blood of Mice

    Science.gov (United States)

    García-Rodríguez, María del Carmen; Hernández-Cortés, Lourdes Montserrat; Altamirano-Lozano, Mario Agustín

    2016-01-01

    This study was conducted to investigate the effects of vanadium pentoxide (V2O5), ascorbic acid (AA), and alpha-tocopherol (α-TOH) on apoptotic, cytotoxic, and genotoxic activity. Groups of five Hsd:ICR mice were treated with the following: (a) vehicle, distilled water; (b) vehicle, corn oil; (c) AA, 100 mg/kg intraperitoneally (ip); (d) α-TOH, 20 mg/kg by gavage; (e) V2O5, 40 mg/kg by ip injection; (f) AA + V2O5; and (g) α-TOH + V2O5. Genotoxic damage was evaluated by examining micronucleated polychromatic erythrocytes (MN-PCE) obtained from the caudal vein at 0, 24, 48, and 72 h after treatments. Induction of apoptosis and cell viability were assessed at 48 h after treatment in nucleated cells of peripheral blood. Treatment with AA alone reduced basal MN-PCE, while V2O5 treatment marginally increased MN-PCE at all times after injection. Antioxidants treatments prior to V2O5 administration decreased MN-PCE compared to the V2O5 group, with the most significant effect in the AA + V2O5 group. The apoptotic cells increased with all treatments, suggesting that this process may contribute to the elimination of the cells with V2O5-induced DNA damage (MN-PCE). The necrotic cells only increased in the V2O5 group. Therefore, antioxidants such as AA and α-TOH can be used effectively to protect or reduce the genotoxic effects induced by vanadium compounds like V2O5. PMID:27413422

  13. Long-term exposure of A549 cells to titanium dioxide nanoparticles induces DNA damage and sensitizes cells towards genotoxic agents.

    Science.gov (United States)

    Armand, Lucie; Tarantini, Adeline; Beal, David; Biola-Clier, Mathilde; Bobyk, Laure; Sorieul, Sephanie; Pernet-Gallay, Karin; Marie-Desvergne, Caroline; Lynch, Iseult; Herlin-Boime, Nathalie; Carriere, Marie

    2016-09-01

    Titanium dioxide nanoparticles (TiO2-NPs) are one of the most produced NPs in the world. Their toxicity has been studied for a decade using acute exposure scenarios, i.e. high exposure concentrations and short exposure times. In the present study, we evaluated their genotoxic impact using long-term and low concentration exposure conditions. A549 alveolar epithelial cells were continuously exposed to 1-50 μg/mL TiO2-NPs, 86% anatase/14% rutile, 24 ± 6 nm average primary diameter, for up to two months. Their cytotoxicity, oxidative potential and intracellular accumulation were evaluated using MTT assay and reactive oxygen species measurement, transmission electron microscopy observation, micro-particle-induced X-ray emission and inductively-coupled plasma mass spectroscopy. Genotoxic impact was assessed using alkaline and Fpg-modified comet assay, immunostaining of 53BP1 foci and the cytokinesis-blocked micronucleus assay. Finally, we evaluated the impact of a subsequent exposure of these cells to the alkylating agent methyl methanesulfonate. We demonstrate that long-term exposure to TiO2-NPs does not affect cell viability but causes DNA damage, particularly oxidative damage to DNA and increased 53BP1 foci counts, correlated with increased intracellular accumulation of NPs. In addition, exposure over 2 months causes cellular responses suggestive of adaptation, characterized by decreased proliferation rate and stabilization of TiO2-NP intracellular accumulation, as well as sensitization to MMS. Taken together, these data underline the genotoxic impact and sensitization effect of long-term exposure of lung alveolar epithelial cells to low levels of TiO2-NPs.

  14. DNA damage and oxidative stress induced by CeO2 nanoparticles in human dermal fibroblasts: Evidence of a clastogenic effect as a mechanism of genotoxicity.

    Science.gov (United States)

    Benameur, Laila; Auffan, Mélanie; Cassien, Mathieu; Liu, Wei; Culcasi, Marcel; Rahmouni, Hidayat; Stocker, Pierre; Tassistro, Virginie; Bottero, Jean-Yves; Rose, Jérôme; Botta, Alain; Pietri, Sylvia

    2015-01-01

    The broad range of applications of cerium oxide (CeO2) nanoparticles (nano-CeO2) has attracted industrial interest, resulting in greater exposures to humans and environmental systems in the coming years. Their health effects and potential biological impacts need to be determined for risk assessment. The aims of this study were to gain insights into the molecular mechanisms underlying the genotoxic effects of nano-CeO2 in relation with their physicochemical properties. Primary human dermal fibroblasts were exposed to environmentally relevant doses of nano-CeO2 (mean diameter, 7 nm; dose range, 6 × 10(-5)-6 × 10(-3) g/l corresponding to a concentration range of 0.22-22 µM) and DNA damages at the chromosome level were evaluated by genetic toxicology tests and compared to that induced in cells exposed to micro-CeO2 particles (mean diameter, 320 nm) under the same conditions. For this purpose, cytokinesis-blocked micronucleus assay in association with immunofluorescence staining of centromere protein A in micronuclei were used to distinguish between induction of structural or numerical chromosome changes (i.e. clastogenicity or aneuploidy). The results provide the first evidence of a genotoxic effect of nano-CeO2, (while not significant with micro-CeO2) by a clastogenic mechanism. The implication of oxidative mechanisms in this genotoxic effect was investigated by (i) assessing the impact of catalase, a hydrogen peroxide inhibitor, and (ii) by measuring lipid peroxidation and glutathione status and their reversal by application of N-acetylcysteine, a precusor of glutathione synthesis in cells. The data are consistent with the implication of free radical-related mechanisms in the nano-CeO2-induced clastogenic effect, that can be modulated by inhibition of cellular hydrogen peroxide release.

  15. Evaluation of the Genotoxic Potential against H2O2-Radical-Mediated DNA Damage and Acute Oral Toxicity of Standardized Extract of Polyalthia longifolia Leaf

    Science.gov (United States)

    Jothy, Subramanion L.; Chen, Yeng; Kanwar, Jagat R.; Sasidharan, Sreenivasan

    2013-01-01

    Medicinal plants have been used in medicoculturally diverse countries around the world, where it is a part of a time-honoured tradition that is respected even today. Polyalthia longifolia leaf extract has been previously reported as an efficient antioxidant in vitro. Hence, the genotoxic effects of P. longifolia leaf were investigated by using plasmid relation, comet, and Allium cepa assay. In the presence of  ∙OH radicals, the DNA in supercoil was start nicked into open circular form, which is the product of the single-stranded cleavage of supercoil DNA and quantified as fragmented separate bands on agarose gel in plasmid relation assay. In the plasmid relation and comet assay, the P. longifolia leaf extract exhibited strong inhibitory effects against H2O2-mediated DNA damage. A dose-dependent increase of chromosome aberrations was also observed in the Allium cepa assay. The abnormalities scored were stickiness, c-mitosis, bridges, and vagrant chromosomes. Micronucleated cells were also observed at the interphase. The results of Allium cepa assay confirmed that the methanol extracts of P. longifolia exerted no significant genotoxic or mitodepressive effects at 100 μg/mL. Thus, this study demonstrated that P. longifolia leaf extract has a beneficial effect against oxidative DNA damage. This experiment is the first report for the protective effect of P. longifolia on DNA damage-induced by hydroxyl radicals. Additionally in acute oral toxicity study, female rats were treated at 5000 mg/kg body weight of P. longifolia leaf extract and observed for signs of toxicity for 14 days. P. longifolia leaf extract did not produce any treatment-related toxic effects in rats. PMID:23878610

  16. Evaluation of the Genotoxic Potential against H2O2-Radical-Mediated DNA Damage and Acute Oral Toxicity of Standardized Extract of Polyalthia longifolia Leaf

    Directory of Open Access Journals (Sweden)

    Subramanion L. Jothy

    2013-01-01

    Full Text Available Medicinal plants have been used in medicoculturally diverse countries around the world, where it is a part of a time-honoured tradition that is respected even today. Polyalthia longifolia leaf extract has been previously reported as an efficient antioxidant in vitro. Hence, the genotoxic effects of P. longifolia leaf were investigated by using plasmid relation, comet, and Allium cepa assay. In the presence of  ∙OH radicals, the DNA in supercoil was start nicked into open circular form, which is the product of the single-stranded cleavage of supercoil DNA and quantified as fragmented separate bands on agarose gel in plasmid relation assay. In the plasmid relation and comet assay, the P. longifolia leaf extract exhibited strong inhibitory effects against H2O2-mediated DNA damage. A dose-dependent increase of chromosome aberrations was also observed in the Allium cepa assay. The abnormalities scored were stickiness, c-mitosis, bridges, and vagrant chromosomes. Micronucleated cells were also observed at the interphase. The results of Allium cepa assay confirmed that the methanol extracts of P. longifolia exerted no significant genotoxic or mitodepressive effects at 100 μg/mL. Thus, this study demonstrated that P. longifolia leaf extract has a beneficial effect against oxidative DNA damage. This experiment is the first report for the protective effect of P. longifolia on DNA damage-induced by hydroxyl radicals. Additionally in acute oral toxicity study, female rats were treated at 5000 mg/kg body weight of P. longifolia leaf extract and observed for signs of toxicity for 14 days. P. longifolia leaf extract did not produce any treatment-related toxic effects in rats.

  17. Genotoxicity of swine effluents.

    Science.gov (United States)

    Techio, V H; Stolberg, J; Kunz, A; Zanin, E; Perdomo, C C

    2011-01-01

    This study aimed at the investigation of genotoxic effects of swine effluents from different stages of a treatment system for swine wastes through bioassay of stamen hairs and micronuclei in Tradescantia (clone BNL 4430). No significant differences (p≥0.05) regarding the genic mutations were found in the bioassay of stamen hairs, independently of the effluent analysed. For the genotoxicity test with micronuclei, the plants exposed to raw wastes, to sludge, and to effluent of the biodigester have presented higher rates of chromosomal damages (micronuclei), with significant differences in relation to the control group and other effluent of the waste treatment system (p≤0.05). The association between the chemical parameters and the genotoxicity data have shown that the variables COD and TKN have presented significant correlation (p≤0.05) with the number of mutagenic events in the tetrads.

  18. Genotoxicity of phthalates.

    Science.gov (United States)

    Erkekoglu, Pınar; Kocer-Gumusel, Belma

    2014-12-01

    Many of the environmental, occupational and industrial chemicals are able to generate reactive oxygen species (ROS) and cause oxidative stress. ROS may lead to genotoxicity, which is suggested to contribute to the pathophysiology of many human diseases, including inflammatory diseases and cancer. Phthalates are ubiquitous environmental chemicals and are well-known peroxisome proliferators (PPs) and endocrine disruptors. Several in vivo and in vitro studies have been conducted concerning the carcinogenic and mutagenic effects of phthalates. Di(2-ethylhexyl)-phthalate (DEHP) and several other phthalates are shown to be hepatocarcinogenic in rodents. The underlying factor in the hepatocarcinogenesis is suggested to be their ability to generate ROS and cause genotoxicity. Several methods, including chromosomal aberration test, Ames test, micronucleus assay and hypoxanthine guanine phosphoribosyl transferase (HPRT) mutation test and Comet assay, have been used to determine genotoxic properties of phthalates. Comet assay has been an important tool in the measurement of the genotoxic potential of many chemicals, including phthalates. In this review, we will mainly focus on the studies, which were conducted on the DNA damage caused by different phthalate esters and protection studies against the genotoxicity of these chemicals.

  19. [Role of beta-carotene in the prevention of genotoxic damage in patients undergoing radiotherapy. Monitoring by the micronucleus test in exfoliative cells of the oral cavity].

    Science.gov (United States)

    Oldini, C; Malusardi, G; Grossi, L; Chiarelli, G

    1992-01-01

    Radiotherapic treatment of patients with carcinoma usually causes genotoxis damage. This has been studied recently using the test of micronuclei in esfoliated cells. This test presents methodologic advantages in compared with the classic citogenetic analysis and as it is carried out on esfolieted cells from the oral cavity it faithfully reflects the genotoxic damage undergone by the cells of the basal layer of the epitelium. The preliminary result obtained so far have confirmed the anticlastogenic activity of beta-carotene in fact, the frequence of micronuclei in esfolieted cells from the oral cavity in patients undergoing radiotherapy or undergoing treatment with beta-carotene is inferior to that of patients undergoing treatment with beta-carotene is inferior to that of patients undergoing radiotherapy without the subministration of carotenoids. Treatment with carotenoids does not influence the therapeutic efficiency of radiotherapy treatment. Therefore, the results seem to confirm that indirect ossidaction processes are involved in the mechanism of the clastogenic action of radiotherapia. The carotenoids seem to be able to contrast validly this undesirable effect without interfering with the desirable therapeutic effect.

  20. Progression of DNA damage induced by a glyphosate-based herbicide in fish (Anguilla anguilla) upon exposure and post-exposure periods--insights into the mechanisms of genotoxicity and DNA repair.

    Science.gov (United States)

    Marques, Ana; Guilherme, Sofia; Gaivão, Isabel; Santos, Maria Ana; Pacheco, Mário

    2014-11-01

    Roundup® is a glyphosate-based herbicide widely used with both agricultural and non-agricultural purposes, which has been demonstrated to represent a risk to non-target aquatic organisms, namely fish. Among the described effects to fish, genotoxicity has been pointed out as one of the most hazardous. However, the genotoxic mechanisms of Roundup® as well as the involvement of the oxidative DNA damage repair system are not entirely understood. Hence, this work aimed to improve the knowledge on the progression of DNA damage upon short-term exposure (3 days) and post-exposure (1-14 days) periods in association with DNA repair processes in Anguilla anguilla exposed to Roundup® (58 and 116 μg L⁻¹). DNA damage in hepatic cells was evaluated by the comet assay improved with the DNA-lesion specific endonucleases FPG and EndoIII. In order to evaluate the oxidative DNA damage repair ability, an in vitro base excision repair (BER) assay was performed, testing hepatic subcellular extracts. Besides the confirmation of the genotoxic potential of this herbicide, oxidative damage was implicit as an important mechanism of genetic damage, which showed to be transient, since DNA integrity returned to the control levels on the first day after cessation of exposure. An increased capacity to repair oxidative DNA damage emerging in the post-exposure period revealed to be a crucial pathway for the A. anguilla recovery; nevertheless, DNA repair machinery showed to be susceptible to inhibitory actions during the exposure period, disclosing another facet of the risk associated with the tested agrochemical.

  1. Inhibition of fried meat-induced rectal DNA damage and altered systemic genotoxicity in humans by crucifera, chlorophyllin, and yogurt

    Science.gov (United States)

    Dietary exposures implicated as reducing or causing risk for colorectal cancer may reduce or cause DNA damage in colon tissue; however, no one has assessed this hypothesis directly in humans. Thus, we enrolled 16 healthy volunteers in a 4-week controlled feeding study where 8 sub...

  2. Inhibition of fried meat-induced colorectal DNA damage and altered systemic genotoxicity in humans by crucifera, chlorophyllin, and yogurt.

    Directory of Open Access Journals (Sweden)

    Daniel T Shaughnessy

    Full Text Available Dietary exposures implicated as reducing or causing risk for colorectal cancer may reduce or cause DNA damage in colon tissue; however, no one has assessed this hypothesis directly in humans. Thus, we enrolled 16 healthy volunteers in a 4-week controlled feeding study where 8 subjects were randomly assigned to dietary regimens containing meat cooked at either low (100°C or high temperature (250°C, each for 2 weeks in a crossover design. The other 8 subjects were randomly assigned to dietary regimens containing the high-temperature meat diet alone or in combination with 3 putative mutagen inhibitors: cruciferous vegetables, yogurt, and chlorophyllin tablets, also in a crossover design. Subjects were nonsmokers, at least 18 years old, and not currently taking prescription drugs or antibiotics. We used the Salmonella assay to analyze the meat, urine, and feces for mutagenicity, and the comet assay to analyze rectal biopsies and peripheral blood lymphocytes for DNA damage. Low-temperature meat had undetectable levels of heterocyclic amines (HCAs and was not mutagenic, whereas high-temperature meat had high HCA levels and was highly mutagenic. The high-temperature meat diet increased the mutagenicity of hydrolyzed urine and feces compared to the low-temperature meat diet. The mutagenicity of hydrolyzed urine was increased nearly twofold by the inhibitor diet, indicating that the inhibitors enhanced conjugation. Inhibitors decreased significantly the mutagenicity of un-hydrolyzed and hydrolyzed feces. The diets did not alter the levels of DNA damage in non-target white blood cells, but the inhibitor diet decreased nearly twofold the DNA damage in target colorectal cells. To our knowledge, this is the first demonstration that dietary factors can reduce DNA damage in the target tissue of fried-meat associated carcinogenesis.ClinicalTrials.gov NCT00340743.

  3. Human RECQ1 is a DNA damage responsive protein required for genotoxic stress resistance and suppression of sister chromatid exchanges.

    Directory of Open Access Journals (Sweden)

    Sudha Sharma

    Full Text Available BACKGROUND: DNA helicases are ubiquitous enzymes that unwind DNA in an ATP-dependent and directionally specific manner. Unwinding of double-stranded DNA is essential for the processes of DNA repair, recombination, transcription, and DNA replication. Five human DNA helicases sharing sequence similarity with the E. coli RecQ helicase have been identified. Three of the human RecQ helicases are implicated in hereditary diseases (Bloom syndrome, Werner syndrome, and Rothmund-Thomson syndrome which display clinical symptoms of premature aging and cancer. RECQ1 helicase is the most highly expressed of the human RecQ helicases; however, a genetic disease has yet not been linked to mutations in the RECQ1 gene, and the biological functions of human RECQ1 in cellular DNA metabolism are not known. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we report that RECQ1 becomes phosphorylated upon DNA damage and forms irradiation-induced nuclear foci that associate with chromatin in human cells. Depletion of RECQ1 renders human cells sensitive to DNA damage induced by ionizing radiation or the topoisomerase inhibitor camptothecin, and results in spontaneous gamma-H2AX foci and elevated sister chromatid exchanges, indicating aberrant repair of DNA breaks. Consistent with a role in homologous recombinational repair, endogenous RECQ1 is associated with the strand exchange protein Rad51 and the two proteins directly interact with high affinity. CONCLUSION/SIGNIFICANCE: Collectively, these results provide the first evidence for a role of human RECQ1 in the response to DNA damage and chromosomal stability maintenance and point to the vital importance of RECQ1 in genome homeostasis.

  4. Is tetrachloroethylene genotoxic or not?

    Science.gov (United States)

    Lovell, David

    2010-09-01

    A recent study published in Mutagenesis, in which the ability of tetrachloroethylene to induce DNA damage, detected by the alkaline comet assay, in mouse tissues (liver and kidney) was examined, has resulted in different interpretations of the data for liver as either positive or negative for genotoxicity. Here, I discuss the statistical approaches used and comment on the different conclusions reached.

  5. Genotoxicity of titanium dioxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Tao Chen

    2014-03-01

    Full Text Available Titanium dioxide nanoparticles (TiO2-NPs, <100 nm are increasingly being used in pharmaceuticals and cosmetics due to the unique properties derived from their small sizes. However, their large surface-area to mass ratio and high redox potential may negatively impact human health and the environment. TiO2-NPs can cause inflammation, pulmonary damage, fibrosis, and lung tumors and they are possibly carcinogenic to humans. Because cancer is a disease involving mutation, there are a large number of studies on the genotoxicity of TiO2-NPs. In this article, we review the results that have been reported in the literature, with a focus on data generated from the standard genotoxicity assays. The data include genotoxicity results from the Ames test, in vitro and in vivo Comet assay, in vitro and in vivo micronucleus assay, sister chromatid exchange assay, mammalian cell hypoxanthine-guanine phosphoribosyl transferase gene assay, the wing somatic mutation and recombination assay, and the mouse phosphatidylinositol glycan, class A gene assay. Inconsistent results have been found in these assays, with both positive and negative responses being reported. The in vitro systems for assessing the genotoxicity of TiO2-NPs have generated a greater number of positive results than the in vivo systems, and tests for DNA and chromosome damage have produced more positive results than the assays measuring gene mutation. Nearly all tests for measuring the mutagenicity of TiO2-NPs were negative. The current data indicate that the genotoxicity of TiO2-NPs is mediated mainly through the generation of oxidative stress in cells.

  6. Detección del daño genotóxico agudo y crónico en una población Detection of acute and chronic genotoxic damage in an occupationally-exposed population

    Directory of Open Access Journals (Sweden)

    Natalia Andrea Giraldo Solano

    2003-03-01

    dysfunctions. This research evaluated, in laboratory personnel at the Universidad Nacional, Medellín, Colombia, the effect of exposition to potentially genotoxic agents, by means of sister chromatids interchange tests (SCI and electrophoresis in single cells gel (comet assay. Standardization of methodological tools to quantify the damage produced by exposition to potentially genotoxic agents was achieved, in order to implement them in occupational health monitoring programs. Evaluation was carried out in two populations, exposed and control, using paired samples. Age, sex and habits were used as criterions for pairing. Comet assay showed punctual damage in the exposed population, while SCI test did not reveal chronic damage. On the other hand, neither habits nor sex showed relation with SCI index, but age did. The usefulness of the comet assay to measure the effect of punctual expositions, and that of SCI as an excellent test to quantify the effect of chronic expositions, makes them indispensable as part of the battery used in genotoxic monitoring studies. As part of the benefits of this research, infrastructure was adapted and some personnel was qualified to carry out occupational health genotoxic monitoring, with the aim of extending this service to the University community and to the private and public sectors.

  7. Cell-Based Genotoxicity Testing

    Science.gov (United States)

    Reifferscheid, Georg; Buchinger, Sebastian

    Genotoxicity test systems that are based on bacteria display an important role in the detection and assessment of DNA damaging chemicals. They belong to the basic line of test systems due to their easy realization, rapidness, broad applicability, high sensitivity and good reproducibility. Since the development of the Salmonella microsomal mutagenicity assay by Ames and coworkers in the early 1970s, significant development in bacterial genotoxicity assays was achieved and is still a subject matter of research. The basic principle of the mutagenicity assay is a reversion of a growth inhibited bacterial strain, e.g., due to auxotrophy, back to a fast growing phenotype (regain of prototrophy). Deeper knowledge of the ­mutation events allows a mechanistic understanding of the induced DNA-damage by the utilization of base specific tester strains. Collections of such specific tester strains were extended by genetic engineering. Beside the reversion assays, test systems utilizing the bacterial SOS-response were invented. These methods are based on the fusion of various SOS-responsive promoters with a broad variety of reporter genes facilitating numerous methods of signal detection. A very important aspect of genotoxicity testing is the bioactivation of ­xenobiotics to DNA-damaging compounds. Most widely used is the extracellular metabolic activation by making use of rodent liver homogenates. Again, genetic engineering allows the construction of highly sophisticated bacterial tester strains with significantly enhanced sensitivity due to overexpression of enzymes that are involved in the metabolism of xenobiotics. This provides mechanistic insights into the toxification and detoxification pathways of xenobiotics and helps explaining the chemical nature of hazardous substances in unknown mixtures. In summary, beginning with "natural" tester strains the rational design of bacteria led to highly specific and sensitive tools for a rapid, reliable and cost effective ­genotoxicity

  8. Assessment of isorhamnetin 3-O-neohesperidoside from Acacia salicina: protective effects toward oxidation damage and genotoxicity induced by aflatoxin B1 and nifuroxazide.

    Science.gov (United States)

    Bouhlel, Ines; Limem, Ilef; Skandrani, Ines; Nefatti, Aicha; Ghedira, Kamel; Dijoux-Franca, Marie-Genevieve; Leila, Chekir-Ghedira

    2010-08-01

    Antioxidant activity of isorhamnetin 3-O-neohesperidoside, isolated from the leaves of Acacia salicina, was determined by the ability of this compound to inhibit xanthine oxidase activity and to scavenge the free radical 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS(.-)) diammonium salt. Antigenotoxic activity was assessed using the SOS chromotest assay. This compound has the ability to scavenge the ABTS(.+) radical by a hydrogen donating mechanism. We also envisaged the study of the antioxidant effect of this compound by the enzymatic xanthine/xanthine oxidase (X/XOD) assay. Results indicated that isorhamnetin 3-O-neohesperidoside was a potent inhibitor of xanthine oxidase and superoxide anion scavengers. Moreover, this compound induced an inhibitory activity against nifuroxazide and aflatoxine B1 (AFB1) induced genotoxicity. Taken together, these observations provide evidence that isorhamnetin 3-O-neohesperidoside isolated from the leaves of A. salicina is able to protect cells against the consequences of oxidative stress.

  9. A predictive toxicogenomics signature to classify genotoxic versus non-genotoxic chemicals in human TK6 cells

    Directory of Open Access Journals (Sweden)

    Andrew Williams

    2015-12-01

    Full Text Available Genotoxicity testing is a critical component of chemical assessment. The use of integrated approaches in genetic toxicology, including the incorporation of gene expression data to determine the DNA damage response pathways involved in response, is becoming more common. In companion papers previously published in Environmental and Molecular Mutagenesis, Li et al. (2015 [6] developed a dose optimization protocol that was based on evaluating expression changes in several well-characterized stress-response genes using quantitative real-time PCR in human lymphoblastoid TK6 cells in culture. This optimization approach was applied to the analysis of TK6 cells exposed to one of 14 genotoxic or 14 non-genotoxic agents, with sampling 4 h post-exposure. Microarray-based transcriptomic analyses were then used to develop a classifier for genotoxicity using the nearest shrunken centroids method. A panel of 65 genes was identified that could accurately classify toxicants as genotoxic or non-genotoxic. In Buick et al. (2015 [1], the utility of the biomarker for chemicals that require metabolic activation was evaluated. In this study, TK6 cells were exposed to increasing doses of four chemicals (two genotoxic that require metabolic activation and two non-genotoxic chemicals in the presence of rat liver S9 to demonstrate that S9 does not impair the ability to classify genotoxicity using this genomic biomarker in TK6cells.

  10. Human genotoxic study carried out two years after oil exposure during the clean-up activities using two different biomarkers.

    NARCIS (Netherlands)

    Biern, G.; Giraldo, J.; Zock, J.P.; Monyarch, G.; Espinosa, A.; Rodríguez-Trigo, G.; Gomez, F.; Pozo-Rodríguez, F.; Barberà, J.A.; Fuster, C.

    2015-01-01

    Micronuclei, comet and chromosome alterations assays are the most widely used biomarkers for determining the genotoxic damage in a population exposed to genotoxic chemicals. While chromosome alterations are an excellent biomarker to detect short- and long-term genotoxic effects, the comet assay only

  11. Environmental genotoxicity: Probing the underlying mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Shugart, L. [Oak Ridge National Lab., TN (United States); Theodorakis, C. [Tennessee Univ., Knoxville, TN (United States)

    1993-12-31

    Environmental pollution is a complex issue because of the diversity of anthropogenic agents, both chemical and physical, that have been detected and catalogued. The consequences to biota from exposure to genotoxic agents present an additional problem because of the potential for these agents to produce adverse change at the cellular and organismal levels. Past studies in genetic toxicology at the Oak Ridge National Laboratory have focused on structural damage to the DNA of environmental species that may occur after exposure to genotoxic agents and the use of this information to document exposure and to monitor remediation. In an effort to predict effects at the population, community and ecosystem levels, current studies in genetic ecotoxicology are attempting to characterize the biological mechanisms at the gene level that regulate and limit the response of an individual organism to genotoxic factors in their environment.

  12. International current of the genotoxicity testing

    Institute of Scientific and Technical Information of China (English)

    HayaM

    2002-01-01

    One of the goals of the genetic toxicology is to assess the risk to humans that derives from genotoxic agents.The risk involves both somatic and germ cells,with damage to the former resulting in cancer and damage to the latter in adverse effects that could be transmitted through generations.It is necessary to consider not only direct effects,but also effects that are the result of analtered environment.To perform an accurate risk assessment.it is necessary to evaluate genotoxic hazards in ways that are appropriate both methodologically and strategically.In establishing a genotoxicity assay system,international cooperation is important because it enables us to incorporate the thoughts of specialists everywhere and to learn of specific regional concerns.Here I will introduce the “Guidance on a Strategy for Testing of Chemicals for Mutagenicity” recently reported by the UK Committee on Mutagenicity (COM) and also I will briefly summarize the activities of the International Workshop on Genotoxicity Test Procedures(IWGTP).The first and the second workshops focused on methodology.we started to include the strategic issues as well as procedures in the third workshop.Starting with the 3rd IWGT,the workshop will become an activity of the International Association of EMSs.

  13. Modulation of Tinospora rumphii and Zinc Salt on DNA Damage in Quinoline-Induced Genotoxicity and Hepatotoxicity in Male Albino Mice

    OpenAIRE

    Roger Salvacion Tan; Lydia M. Bajo

    2014-01-01

    Tinospora rumphii (T. rumphii) is a folkloric medicinal plant that is widely distributed in Asia and Africa. It has been widely used by locals to treat many diseases including jaundice, which is a manifestation of liver damage. We investigated the action of T. rumphii crude extract together with zinc sulphate, a known tumor modulator, on hepatic injuries induced by intraperitoneal (i.p) injections of quinoline on albino mice. The hepatotoxic effect was assessed by bilirubin concentration in t...

  14. Anti-genotoxic effect of Aloysia triphylla infusion against acrylamide-induced DNA damage as shown by the comet assay technique.

    Science.gov (United States)

    Zamorano-Ponce, E; Morales, C; Ramos, D; Sepúlveda, C; Cares, S; Rivera, P; Fernández, J; Carballo, M A

    2006-02-28

    Aloysia triphylla a perennial, bushy plant originally from South America has long been used in traditional medicine. Its aqueous extract contains considerable amounts of polyphenolic compounds, namely flavonoids and phenolic acids. In view of the interest in natural phenolic compounds as antioxidant in preventive medicine, this study was undertaken to investigate the chemoprotective effects of cedron leaves infusion against the genetic damage induced by acrylamide (AA) by using the alkaline version of the comet assay technique. Mice were separated in nine groups (eight animals each): (I) untreated, (II) negative control, (III) treated with infusion of cedron leaves 5%, 20 days twice a day, (IV) treated with AA (5 mg/kg b.w.), (V) treated with AA (20 mg/kg b.w.), (VI) treated with AA (30 mg/kg b.w.), (VII) treated with AA (50 mg/kg b.w.), (VIII) pretreated with infusion and treated with AA (50 mg/kg b.w.) and (IX) positive control (cyclophosphamide, 20 mg/kg b.w.). Three hundred blast cells were digitally evaluated per animal from three different slides (100 each). Media of tail moment (TM) values were analyzed by ANOVA test. No statistical differences (p>0.05) were found between untreated animals, negative control and infusion-treated mice. A single dose of AA-induced genetic damage as revealed by a statistically significant increase in TM values (p0.05) and exhibit statistical differences from animals treated only with AA (p<0.01). Cell viability was at least 90% in all cases as measured by the trypan blue exclusion method. The ferric reducing ability of plasma (FRAP) method reveals that the plasma of infusion-treated mice has a significantly higher antioxidant capacity than plasma from controls (p<0.01). The results suggest that the infusion could exerts an in vivo chemo protective action, probably due to its scavenging potency towards free radicals.

  15. Genotoxicity investigations on nanomaterials.

    Science.gov (United States)

    Oesch, Franz; Landsiedel, Robert

    2012-07-01

    This review is based on the lecture presented at the April 2010 nanomaterials safety assessment Postsatellite to the 2009 EUROTOX Meeting and summarizes genotoxicity investigations on nanomaterials published in the open scientific literature (up to 2008). Special attention is paid to the relationship between particle size and positive versus negative outcome, as well as the dependence of the outcome on the test used. Salient conclusions and outstanding recommendations emerging from the information summarized in this review are as follows: recognize that nanomaterials are not all the same; therefore know and document what nanomaterial has been tested and in what form; take nanomaterials specific properties into account; in order to make your results comparable with those of others and on other nanomaterials: use or at least include in your studies standardized methods; use in vivo studies to put in vitro results into perspective; take uptake and distribution of the nanomaterial into account; and in order to become able to make extrapolations to risk for human: learn about the mechanism of nanomaterials genotoxic effects. Past experience with standard non-nanosubstances already had shown that mechanisms of genotoxic effects can be complex and their elucidation can be demanding, while there often is an immediate need to assess the genotoxic hazard. Thus, a practical and pragmatic approach to genotoxicity investigations of novel nanomaterials is the use of a battery of standard genotoxicity testing methods covering a wide range of mechanisms. Application of these standard methods to nanomaterials demands, however, adaptations, and the interpretation of results from the genotoxicity testing of nanomaterials needs additional considerations exceeding those used for standard size materials.

  16. "Aspartame: A review of genotoxicity data".

    Science.gov (United States)

    Kirkland, David; Gatehouse, David

    2015-10-01

    Aspartame is a methyl ester of a dipeptide of aspartic acid and phenylalanine. It is 200× sweeter than sucrose and is approved for use in food products in more than 90 countries around the world. Aspartame has been evaluated for genotoxic effects in microbial, cell culture and animal models, and has been subjected to a number of carcinogenicity studies. The in vitro and in vivo genotoxicity data available on aspartame are considered sufficient for a thorough evaluation. There is no evidence of induction of gene mutations in a series of bacterial mutation tests. There is some evidence of induction of chromosomal damage in vitro, but this may be an indirect consequence of cytotoxicity. The weight of evidence from in vivo bone marrow micronucleus, chromosomal aberration and Comet assays is that aspartame is not genotoxic in somatic cells in vivo. The results of germ cell assays are difficult to evaluate considering limited data available and deviations from standard protocols. The available data therefore support the conclusions of the European Food Safety Authority (EFSA) that aspartame is non-genotoxic.

  17. Genotoxic effect of alkaloids

    Directory of Open Access Journals (Sweden)

    J. A. P. Henriques

    1991-01-01

    Full Text Available Because of the increase use of alkaloids in general medical practice in recent years, it is of interest to determine genotoxic, mutagenic and recombinogenic response to different groups of alkaloids in prokaryotic and eucaryotic organisms. Reserpine, boldine and chelerythrine did not show genotoxicity response in the SOS-Chromotest whereas skimmianine showed genotixicity in the presence of a metabolic activation mixture. Voacristine isolated fromthe leaves of Ervatamia coronaria shows in vivo cytostatic and mutagenic effects in Saccharomyces cerevisiae hapioids cells. The Rauwolfia alkaloid (reserpine was not able to induce reverse mutation and recombinational mitotic events (crossing-over and gene conversion in yeast diploid strain XS2316.

  18. Signs of deferasirox genotoxicity

    OpenAIRE

    Ila, Hasan Basri; Topaktas, Mehmet; Arslan, Mehmet; Büyükleyla, Mehmet

    2013-01-01

    Iron overload is a major health problem for patients who have to have continuous blood transfusions. It brings some metabolic problems together. Various iron chelating agents are being used for treatment of hemochromatosis which arises from excess iron accumulation. This study was conducted with the aim of determining whether deferasirox used as an iron chelator in patients with hemochromatosis has genotoxic effects. Commercial form of deferasirox, Exjade was used as test material. Test mater...

  19. Cytotoxicity and genotoxicity of butyl cyclohexyl phthalate.

    Science.gov (United States)

    Köksal, Çinel; Nalbantsoy, Ayse; Karabay Yavaşoğlu, N Ülkü

    2016-03-01

    Butyl cyclohexyl phthalate (BCP) is frequently used in personal care products, medical and household applications. The aim of this study is therefore to evaluate possible cytotoxicity and genotoxicity of BCP using in vitro and in vivo assays. The in vitro cytotoxic effect of BCP was investigated on mouse fibroblastic cell line (L929 cells) by MTT assay. The result showed that BCP inhibits cell proliferation in a concentration-dependent manner (IC50 value = 0.29 µg/mL). For genotoxicity assessment, tested concentrations of BCP demonstrated mutagenic activity in the presence of S9 mix with the Salmonella strain TA100 in the Ames test. Results showed that BCP is a secondary mutagenic substance even in low concentrations. The data obtained from 28-days repeated toxicity tests on mice revealed that BCP caused abnormalities of chromosome number, in a dose-dependent manner. Additionally, DNA damage, particularly DNA strand breaks, was assessed by Comet assay. The test result shows that BCP seemed to have genotoxic potential at a high level of exposure.

  20. In vivo genotoxicity of estragole in male F344 rats.

    Science.gov (United States)

    Ding, Wei; Levy, Dan D; Bishop, Michelle E; Pearce, Mason G; Davis, Kelly J; Jeffrey, Alan M; Duan, Jian-Dong; Williams, Gary M; White, Gene A; Lyn-Cook, Lascelles E; Manjanatha, Mugimane G

    2015-05-01

    Estragole, a naturally occurring constituent of various herbs and spices, is a rodent liver carcinogen which requires bio-activation. To further understand the mechanisms underlying its carcinogenicity, genotoxicity was assessed in F344 rats using the comet, micronucleus (MN), and DNA adduct assays together with histopathological analysis. Oxidative damage was measured using human 8-oxoguanine-DNA-N-glycosylase (hOGG1) and EndonucleaseIII (EndoIII)-modified comet assays. Results with estragole were compared with the structurally related genotoxic carcinogen, safrole. Groups of seven-week-old male F344 rats received corn oil or corn oil containing 300, 600, or 1,000 mg/kg bw estragole and 125, 250, or 450 mg/kg bw safrole by gavage at 0, 24, and 45 hr and terminated at 48 hr. Estragole-induced dose-dependent increases in DNA damage following EndoIII or hOGG1 digestion and without enzyme treatment in liver, the cancer target organ. No DNA damage was detected in stomach, the non-target tissue for cancer. No elevation of MN was observed in reticulocytes sampled from peripheral blood. Comet assays, both without digestion or with either EndoIII or hOGG1 digestion, also detected DNA damage in the liver of safrole-dosed rats. No DNA damage was detected in stomach, nor was MN elevated in peripheral blood following dosing with safrole suggesting that, as far both safrole and estragole, oxidative damage may contribute to genotoxicity. Taken together, these results implicate multiple mechanisms of estragole genotoxicity. DNA damage arises from chemical-specific interaction and is also mediated by oxidative species.

  1. Evaluation of Cytotoxicity and Genotoxicity of Acacia aroma Leaf Extracts

    Directory of Open Access Journals (Sweden)

    C. M. Mattana

    2014-01-01

    Full Text Available Acacia aroma, native plant from San Luis, Argentina, is commonly used as antiseptic and for healing of wounds. The present study was conducted to investigate the in vitro cytotoxicity and genotoxicity of hot aqueous extract (HAE and ethanolic extract (EE of A. aroma. The cytotoxic activity was assayed by neutral red uptake assay on Vero cell. Cell treatment with a range from 100 to 5000 μg/mL of HAE and EE showed that 500 μg/mL and 100 μg/mL were the maximum noncytotoxic concentrations, respectively. The CC50 was 658 μg/mL for EE and 1020 μg/mL for HAE. The genotoxicity was tested by the single-cell gel electrophoresis comet assay. The results obtained in the evaluation of DNA cellular damage exposed to varied concentrations of the HAE showed no significant genotoxic effect at range of 1–20 mg/mL. The EE at 20 mg/mL showed moderate genotoxic effect related to the increase of the DNA percentage contained in tail of the comet; DNA was classified in category 2. At concentrations below 5 mg/mL, the results of cytotoxicity and genotoxicity of aqueous and ethanolic extracts of Acacia aroma guarantee the safety at cell and genomic level. However further studies are needed for longer periods including animal models to confirm the findings.

  2. Assessment of genotoxic effects of flumorph by the comet assay in mice organs.

    Science.gov (United States)

    Zhang, T; Zhao, Q; Zhang, Y; Ning, J

    2014-03-01

    The present study investigated the genotoxic effects of flumorph in various organs (brain, liver, spleen, kidney and sperm) of mice. The DNA damage, measured as comet tail length (µm), was determined using the alkaline comet assay. The comet assay is a sensitive assay for the detection of genotoxicity caused by flumorph using mice as a model. Statistically significant increases in comet assay for both dose-dependent and duration-dependent DNA damage were observed in all the organs assessed. The organs exhibited the maximum DNA damage in 96 h at 54 mg/kg body weight. Brain showed maximum DNA damage followed by spleen > kidney > liver > sperm. Our data demonstrated that flumorph had induced systemic genotoxicity in mammals as it caused DNA damage in all tested vital organs, especially in brain and spleen.

  3. Evaluation of genotoxicity of combined soil pollution by cadmium and imidacloprid

    Institute of Scientific and Technical Information of China (English)

    LIN; Aijun; ZHU; Yongguan; TONG; Yiping

    2005-01-01

    Cadmium (Cd) is one of the important pollutants of soil and the genotoxicity of Cd-contaminated soil was studied in combination with imidacloprid. The single cell gel electrophoresis or comet assay was used to quantify DNA strand breaks as a measure of DNA damage induced by Cd and imidacloprid contamination in soil. The soil was artificially contaminated by Cd 2 h at 25℃ and were used in the comet assay. DNA damage was measured as the values of percentage of nuclei with tails, tail length, tail DNA, tail moment (TM), and Olive tail moment (OTM). DNA damages of root tips of Vicia faba increased after Cd treatment and there were dose-related increases in DNA damage measured as these parameters. However, the addition of imidacloprid further increased the DNA damage. These data confirmed the genotoxic effect of Cd to plants, and that the combined pollution with imidacloprid can enhance the genotoxicity of Cd.

  4. Genotoxicity Studies Performed in the Ecuadorian Population

    Directory of Open Access Journals (Sweden)

    César Paz-y-Miño

    2012-01-01

    Full Text Available Genotoxicity studies in Ecuador have been carried out during the past two decades. The focuses of the research were mainly the area of environmental issues, where the populations have been accidentally exposed to contaminants and the area of occupational exposure of individuals at the workplace. This paper includes studies carried out in the population of the Amazon region, a zone known for its rich biodiversity as well as for the ecological damage caused by oil spills and chemical sprayings whose consequences continue to be controversial. Additionally, we show the results of studies comprised of individuals occupationally exposed to toxic agents in two very different settings: flower plantation workers exposed to pesticide mixtures and X-ray exposure of hospital workers. The results from these studies confirm that genotoxicity studies can help evaluate current conditions and prevent further damage in the populations exposed to contaminants. As such, they are evidence of the need for biomonitoring employers at risk, stricter law enforcement regarding the use of pesticides, and increasingly conscientious oil extraction activities.

  5. Genotoxicity studies performed in the ecuadorian population.

    Science.gov (United States)

    Paz-Y-Miño, César; Cumbal, Nadia; Sánchez, María Eugenia

    2012-01-01

    Genotoxicity studies in Ecuador have been carried out during the past two decades. The focuses of the research were mainly the area of environmental issues, where the populations have been accidentally exposed to contaminants and the area of occupational exposure of individuals at the workplace. This paper includes studies carried out in the population of the Amazon region, a zone known for its rich biodiversity as well as for the ecological damage caused by oil spills and chemical sprayings whose consequences continue to be controversial. Additionally, we show the results of studies comprised of individuals occupationally exposed to toxic agents in two very different settings: flower plantation workers exposed to pesticide mixtures and X-ray exposure of hospital workers. The results from these studies confirm that genotoxicity studies can help evaluate current conditions and prevent further damage in the populations exposed to contaminants. As such, they are evidence of the need for biomonitoring employers at risk, stricter law enforcement regarding the use of pesticides, and increasingly conscientious oil extraction activities.

  6. p53 modulates the AMPK inhibitor compound C induced apoptosis in human skin cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Shi-Wei [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Wu, Chun-Ying [Division of Gastroenterology and Hepatology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Wang, Yen-Ting [Department of Medical Research and Education, Cheng Hsin General Hospital, Taipei, Taiwan (China); Kao, Jun-Kai [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Department of Pediatrics, Children' s Hospital, Changhua Christian Hospital, Changhua, Taiwan (China); Lin, Chi-Chen; Chang, Chia-Che; Mu, Szu-Wei; Chen, Yu-Yu [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Chiu, Husan-Wen [Institute of Biotechnology, National Cheng-Kung University, Tainan, Taiwan (China); Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan (China); Chang, Chuan-Hsun [Department of Surgical Oncology, Cheng Hsin General Hospital, Taipei, Taiwan (China); Department of Nutrition Therapy, Cheng Hsin General Hospital, Taipei, Taiwan (China); School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan (China); Liang, Shu-Mei [Institute of Biotechnology, National Cheng-Kung University, Tainan, Taiwan (China); Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan (China); Chen, Yi-Ju [Department of Dermatology, Taichung Veterans General Hospital, Taichung, Taiwan (China); Huang, Jau-Ling [Department of Bioscience Technology, Chang Jung Christian University, Tainan, Taiwan (China); Shieh, Jeng-Jer, E-mail: shiehjj@vghtc.gov.tw [Institute of Biomedical Sciences, National Chung Hsing University, Taichung, Taiwan (China); Department of Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan (China)

    2013-02-15

    Compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), has been reported to cause apoptotic cell death in myeloma, breast cancer cells and glioma cells. In this study, we have demonstrated that compound C not only induced autophagy in all tested skin cancer cell lines but also caused more apoptosis in p53 wildtype skin cancer cells than in p53-mutant skin cancer cells. Compound C can induce upregulation, phosphorylation and nuclear translocalization of the p53 protein and upregulate expression of p53 target genes in wildtype p53-expressing skin basal cell carcinoma (BCC) cells. The changes of p53 status were dependent on DNA damage which was caused by compound C induced reactive oxygen species (ROS) generation and associated with activated ataxia-telangiectasia mutated (ATM) protein. Using the wildtype p53-expressing BCC cells versus stable p53-knockdown BCC sublines, we present evidence that p53-knockdown cancer cells were much less sensitive to compound C treatment with significant G2/M cell cycle arrest and attenuated the compound C-induced apoptosis but not autophagy. The compound C induced G2/M arrest in p53-knockdown BCC cells was associated with the sustained inactive Tyr15 phosphor-Cdc2 expression. Overall, our results established that compound C-induced apoptosis in skin cancer cells was dependent on the cell's p53 status. - Highlights: ► Compound C caused more apoptosis in p53 wildtype than p53-mutant skin cancer cells. ► Compound C can upregulate p53 expression and induce p53 activation. ► Compound C induced p53 effects were dependent on ROS induced DNA damage pathway. ► p53-knockdown attenuated compound C-induced apoptosis but not autophagy. ► Compound C-induced apoptosis in skin cancer cells was dependent on p53 status.

  7. Absence of genotoxic effects of the chalcone (E)-1-(2-hydroxyphenyl)-3-(4-methylphenyl)-prop-2-en-1-one) and its potential chemoprevention against DNA damage using in vitro and in vivo assays

    Science.gov (United States)

    2017-01-01

    The chalcone (E)-1-(2-hydroxyphenyl)-3-(4-methylphenyl)-prop-2-en-1-one), or 2HMC, displays antileishmanial, antimalarial, and antioxidant activities. The aim of this study was to investigate the cytotoxic, genotoxic, mutagenic, and protective effects of 2HMC using the Ames mutagenicity test, the mouse bone marrow micronucleus test, and the comet assay in mice. In the assessment using the Ames test, 2HMC did not increase the number of His+ revertants in Salmonella typhimurium strains, demonstrating lack of mutagenicity. 2HMC showed no significant increase in micronucleated polychromatic erythrocyte frequency (MNPCE) in the micronucleus test, or in DNA strand breaks using the comet assay, evidencing absence of genotoxicity. Regarding cytotoxicity, 2HMC exhibited moderate cytotoxicity in mouse bone marrow cells by micronucleus test. 2HMC showed antimutagenic action in co-administration with the positive controls, sodium azide (SA) and 4-nitroquinoline-1-oxide (4NQO), in the Ames test. Co-administered and mainly pre-administered with cyclophosphamide (CPA), 2HMC caused a decrease in the frequency of MNPCE using the micronucleus test and in DNA strand breaks using the comet assay. Thus, 2HMC exhibited antimutagenic and antigenotoxic effects, displaying a DNA-protective effect against CPA, SA, and 4NQO carcinogens. In conclusion, 2HMC presented antimutagenic, antigenotoxic and moderate cytotoxic effects; therefore it is a promising molecule for cancer prevention. PMID:28207781

  8. Is the Comet Assay a Sensitive Procedure for Detecting Genotoxicity?

    Directory of Open Access Journals (Sweden)

    Satomi Kawaguchi

    2010-01-01

    Full Text Available 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

  9. Genotoxic activity of praziquantel.

    Science.gov (United States)

    Montero, R; Ostrosky, P

    1997-12-01

    Praziquantel is a synthetic drug with a remarkable activity against parasites, particularly treamatodes and cestodes. Initial genotoxicity tests used a spectrum of endpoints including tests in bacteria, yeasts, mammalian cells and Drosophila and each one gave negative results. Effects on reproductive cells of mice were negative as well. However, host mediated studies in mice and humans were contradictory and a comutagenic effect with several mutagens and carcinogens was found. Later studies, including monitoring in humans and pigs have shown that Praziquantel induces a greater frequency of hyperploid lymphocytes as well as structural chromosomal aberrations, but not in all the individuals treated. In vitro studies have demonstrated that Praziquantel can induce micronuclei in syrian hamster embryonic (SHE) cells and in lymphocytes of some individuals. The same was found about structural chromosomal aberrations. Fetal death and fetal resorption were found when Praziquantel was administered in high doses to pregnant rats between the 6th and 10th day of gestation. Due to its efficiency as a parasiticide, Praziquantel is in use in Latin-American, Asiatic, African and East-European countries where infections by trematodes and cestodes are frequent. However, the extensive use of Praziquantel in multiple reinfections, in non-infected and non-diagnosed individuals for prevention, in higher doses or repeated doses for cysticercosis treatment and in individuals exposed to environmental mutagens, in conjunction with new findings about its metabolism and genotoxic properties, make it necessary to further evaluate the potential of this drug not only to be mutagenic per se, but to contribute in the development of neoplasm.

  10. Genotoxic potential of nonsteroidal hormones

    Directory of Open Access Journals (Sweden)

    Topalović Dijana

    2015-01-01

    Full Text Available Hormones are cellular products involved in the regulation of a large number of processes in living systems, and which by their actions affect the growth, function and metabolism of cells. Considering that hormones are compounds normally present in the organism, it is important to determine if they can, under certain circumstances, lead to genetic changes in the hereditary material. Numerous experimental studies in vitro and in vivo in different systems, from bacteria to mammals, dealt with the mutagenic and genotoxic effects of hormones. This work presents an overview of the research on genotoxic effects of non­steroidal hormones, although possible changes of genetic material under their influence have not still been known enough, and moreover, investigations on their genotoxic influence have given conflicting results. The study results show that mechanisms of genotoxic effect of nonsteroidal hormones are manifested through the increase of oxidative stress by arising reactive oxygen species. A common mechanism of ROS occurence in thyroid hormones and catecholamines is through metabolic oxidation of their phenolic groups. Manifestation of insulin genotoxic effect is based on production of ROS by activation of NADPH isophorms, while testing oxytocin showed absence of genotoxic effect. Considering that the investigations on genotoxicity of nonsteroidal hormones demonstrated both positive and negative results, the explanation of this discordance involve limitations of test systems themselves, different cell types or biological species used in the experiments, different level of reactivity in vitro and in vivo, as well as possible variations in a tissue-specific expression. Integrated, the provided data contribute to better understanding of genotoxic effect of nonsteroidal hormones and point out to the role and mode of action of these hormones in the process of occurring of effects caused by oxidative stress. [Projekat Ministarstva nauke Republike

  11. Genotoxicity of diuron and glyphosate in oyster spermatozoa and embryos.

    Science.gov (United States)

    Akcha, F; Spagnol, C; Rouxel, J

    2012-01-15

    We investigated the effects of genotoxicant exposure in gametes and embryos to find a possible link between genotoxicity and reproduction/developmental impairment, and explore the impact of chemical genotoxicity on population dynamics. Our study focused on the genotoxic effects of two herbicides on oyster gametes and embryos: glyphosate (both as an active substance and in the Roundup formulation) and diuron. France is Europe's leading consumer of agrochemical substances and as such, contamination of France's coastal waters by pesticides is a major concern. Glyphosate and diuron are among the most frequently detected herbicides in oyster production areas; as oyster is a specie with external reproduction, its gametes and embryos are in direct contact with the surrounding waters and are hence particularly exposed to these potentially dangerous substances. In the course of this study, differences in genotoxic and embryotoxic responses were observed in the various experiments, possibly due to differences in pollutant sensitivity between the tested genitor lots. Glyphosate and Roundup had no effect on oyster development at the concentrations tested, whereas diuron significantly affected embryo-larval development from the lowest tested concentration of 0.05 μg L⁻¹, i.e. an environmentally realistic concentration. Diuron may therefore have a significant impact on oyster recruitment rates in the natural environment. Our spermiotoxicity study revealed none of the tested herbicides to be cytotoxic for oyster spermatozoa. However, the alkaline comet assay showed diuron to have a significant genotoxic effect on oyster spermatozoa at concentrations of 0.05 μg L⁻¹ upwards. Conversely, no effects due to diuron exposure were observed on sperm mitochondrial function or acrosomal membrane integrity. Although our initial results showed no negative effect on sperm function, the possible impact on fertilization rate and the consequences of the transmission of damaged DNA for

  12. What is Comet assay not telling us: AFLP reveals wider aspects of genotoxicity.

    Science.gov (United States)

    Šrut, Maja; Štambuk, Anamaria; Klobučar, Göran I V

    2013-06-01

    DNA damage detected by genotoxicity biomarkers such as the Comet assay is not always a reliable indicator of the consequences that genotoxic agents can have on the genome integrity of the exposed organisms. Therefore, to reveal the existence of more permanent alterations of DNA structure after genotoxic stress, the RTG-2 rainbow trout cell line was exposed for 3 days to benzo[a]pyrene (B[a]P, 0.1-10 μM) and ethyl methanesulfonate (EMS, 0.1-1mM) followed by 3 days of recovery period. Primary DNA damage was evaluated by the Comet assay and DNA alterations were assessed using AFLP (amplified fragment length polymorphism). Qualitative and quantitative modifications in AFLP profiles were analyzed in order to detect genetic alterations arising from mutation events and/or DNA damage. Significant induction in DNA damage measured by the Comet assay was noticed after B[a]P treatment at all concentrations but values returned to the control level after recovery. Exposure to EMS induced significant DNA damage only at the highest concentration and damage persisted after the recovery period. AFLP profiles detected DNA alterations even when Comet assay indicated complete DNA repair, revealing more persistent damage. Since such DNA damage can impair its structure and function, Comet assay results should preferably be supplemented with other methods in order to predict the consequences of genotoxic insult more accurately.

  13. NER and HR pathways act sequentially to promote UV-C-induced germ cell apoptosis in Caenorhabditis elegans

    OpenAIRE

    Stergiou, L.; Eberhard, R; Doukoumetzidis, K; Hengartner, M. O.

    2010-01-01

    Ultraviolet (UV) radiation-induced DNA damage evokes a complex network of molecular responses, which culminate in DNA repair, cell cycle arrest and apoptosis. Here, we provide an in-depth characterization of the molecular pathway that mediates UV-C-induced apoptosis of meiotic germ cells in the nematode Caenorhabditis elegans. We show that UV-C-induced DNA lesions are not directly pro-apoptotic. Rather, they must first be recognized and processed by the nucleotide excision repair (NER) pathwa...

  14. Genotoxicity evaluation of sesamin and episesamin.

    Science.gov (United States)

    Hori, Hisako; Takayanagi, Tomomi; Kamada, Yoko; Shimoyoshi, Satomi; Ono, Yoshiko; Kitagawa, Yoshinori; Shibata, Hiroshi; Nagao, Minako; Fujii, Wataru; Sakakibara, Yutaka

    2011-02-03

    Sesamin is a major lignan that is present in sesame seeds and oil. Sesamin is partially converted to its stereoisomer, episesamin, during the refining process of non-roasted sesame seed oil. We evaluated the genotoxicity of these substances through the following tests: a bacterial reverse mutation assay (Ames test), a chromosomal aberration test in cultured Chinese hamster lung cells (CHL/IU), a bone marrow micronucleus (MN) test in Crlj:CD1 (ICR) mice, and a comet assay using the liver of Sprague-Dawley (SD) rats. Episesamin showed negative results in the Ames test with and without S9 mix, in the in vitro chromosomal aberration test with and without S9 mix, and in the in vivo comet assay. Sesamin showed negative results in the Ames test with and without S9 mix. In the in vitro chromosomal aberration test, sesamin did not induce chromosomal aberrations in the absence of S9 mix, but induced structural abnormalities at cytotoxic concentrations in the presence of S9 mix. Oral administration of sesamin at doses up to 2.0g/kg did not cause a significant increase in either the percentage of micronucleated polychromatic erythrocytes in the in vivo bone marrow MN test or in the % DNA in the comet tails in the in vivo comet assay of liver cells. These findings indicate that sesamin does not damage DNA in vivo and that sesamin and episesamin have no genotoxic activity.

  15. Evaluation of perfluorooctanoate for potential genotoxicity

    Directory of Open Access Journals (Sweden)

    John L. Butenhoff

    2014-01-01

    Full Text Available Perfluorooctanoate (PFOA is a fully fluorinated eight-carbon fatty acid analog with exceptional stability toward degradation that has been used as an industrial surfactant and has been detected in environmental and biological matrices. Exposures to PFOA in the workplace and in the environment have continuously stimulated investigations into its potential human health hazards. In this article, the results of fifteen unpublished genotoxicity assays conducted with perfluorooctanoate (as either the linear or linear/branched ammonium salt (APFO or the linear/branched sodium salt are reported and include: seven mutation assays (three in vitro reverse mutation assays with histidine auxotrophic strains of Salmonella typhimurium, two in vitro reverse mutation assays with the tryptophan auxotrophic Escherichia coli WP2uvr strain, one in vitro mitotic recombination (gene conversion assay with Saccharomyces cerevisiae D4, and an in vitro Chinese hamster ovary (CHO HGPRT forward mutation assay; seven studies to assess potential for chromosomal damage (three in vitro CHO chromosomal aberration studies, an in vitro human whole blood lymphocyte chromosomal aberration study, and three in vivo mouse micronucleus assays; and an in vitro C3H 10T1/2 cell transformation assay. Although PFOA has not been demonstrated to be metabolized, all in vitro assays were conducted both in the presence and in the absence of a mammalian hepatic microsomal activation system. These assays were originally described in twelve contract laboratory reports which have been available via the United States Environmental Protection Agency public docket (Administrative Record 226 for over a decade; however, the details of these assays have not been published previously in the open scientific literature. With the exception of limited positive findings at high and cytotoxic concentrations in some assay trials which reflected the likely consequence of cytotoxic disruption of normal cellular

  16. Genotoxicity of pyrrolizidine alkaloids.

    Science.gov (United States)

    Chen, Tao; Mei, Nan; Fu, Peter P

    2010-04-01

    Pyrrolizidine alkaloids (PAs) are common constituents of many plant species around the world. PA-containing plants are probably the most common poisonous plants affecting livestock and wildlife. They can inflict harm to humans through contaminated food sources, herbal medicines and dietary supplements. Half of the identified PAs are genotoxic and many of them are tumorigenic. The mutagenicity of PAs has been extensively studied in different biological systems. Upon metabolic activation, PAs produce DNA adducts, DNA cross-linking, DNA breaks, sister chromatid exchange, micronuclei, chromosomal aberrations, gene mutations and chromosome mutations in vivo and in vitro. PAs induced mutations in the cII gene of rat liver and in the p53 and K-ras genes of mouse liver tumors. It has been suggested that all PAs produce a set of (+/-)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine-derived DNA adducts and similar types of gene mutations. The signature types of mutations are G : C --> T : A transversion and tandem base substitutions. Overall, PAs are mutagenic in vivo and in vitro and their mutagenicity appears to be responsible for the carcinogenesis of PAs.

  17. Beryllium: genotoxicity and carcinogenicity.

    Science.gov (United States)

    Gordon, Terry; Bowser, Darlene

    2003-12-10

    Beryllium (Be) has physical-chemical properties, including low density and high tensile strength, which make it useful in the manufacture of products ranging from space shuttles to golf clubs. Despite its utility, a number of standard setting agencies have determined that beryllium is a carcinogen. Only a limited number of studies, however, have addressed the underlying mechanisms of the carcinogenicity and mutagenicity of beryllium. Importantly, mutation and chromosomal aberration assays have yielded somewhat contradictory results for beryllium compounds and whereas bacterial tests were largely negative, mammalian test systems showed evidence of beryllium-induced mutations, chromosomal aberrations, and cell transformation. Although inter-laboratory differences may play a role in the variability observed in genotoxicity assays, it is more likely that the different chemical forms of beryllium have a significant effect on mutagenicity and carcinogenicity. Because workers are predominantly exposed to airborne particles which are generated during the machining of beryllium metal, ceramics, or alloys, testing of the mechanisms of the mutagenic and carcinogenic activity of beryllium should be performed with relevant chemical forms of beryllium.

  18. Evaluation of Genotoxic Pressure along the Sava River

    Science.gov (United States)

    Kračun-Kolarević, Margareta; Kostić, Jovana; Simonović, Predrag; Simić, Vladica; Milošković, Aleksandra; Reischer, Georg; Farnleitner, Andreas; Gačić, Zoran; Milačič, Radmila; Zuliani, Tea; Vidmar, Janja; Pergal, Marija; Piria, Marina; Paunović, Momir; Vuković-Gačić, Branka

    2016-01-01

    In this study we have performed a comprehensive genotoxicological survey along the 900 rkm of the Sava River. In total, 12 sites were chosen in compliance with the goals of GLOBAQUA project dealing with the effects of multiple stressors on biodiversity and functioning of aquatic ecosystems. The genotoxic potential was assessed using a complex battery of bioassays performed in prokaryotes and aquatic eukaryotes (freshwater fish). Battery comprised evaluation of mutagenicity by SOS/umuC test in Salmonella typhimurium TA1535/pSK1002. The level of DNA damage as a biomarker of exposure (comet assay) and biomarker of effect (micronucleus assay) and the level of oxidative stress as well (Fpg—modified comet assay) was studied in blood cells of bleak and spirlin (Alburnus alburnus/Alburnoides bipunctatus respectively). Result indicated differential sensitivity of applied bioassays in detection of genotoxic pressure. The standard and Fpg—modified comet assay showed higher potential in differentiation of the sites based on genotoxic potential in comparison with micronucleus assay and SOS/umuC test. Our data represent snapshot of the current status of the river which indicates the presence of genotoxic potential along the river which can be traced to the deterioration of quality of the Sava River by communal and industrial wastewaters. The major highlight of the study is that we have provided complex set of data obtained from a single source (homogeneity of analyses for all samples). PMID:27631093

  19. Mutagenicity and genotoxicity of coal fly ash water leachate

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, R.; Mukherjee, A. [University of Calcutta, Calcutta (India). Dept. of Botany

    2009-03-15

    Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals - sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significantconcentration-dependent increases in DNA damage in whole blood cells, lymphocytes, and in Nicotiana plants. The comet parameters show increases in tail DNA percentage (%), tail length (mu m), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations.

  20. Detection of genotoxic and non-genotoxic carcinogens in Xpc{sup −/−}p53{sup +/−} mice

    Energy Technology Data Exchange (ETDEWEB)

    Melis, Joost P.M. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands); Speksnijder, Ewoud N. [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands); Kuiper, Raoul V. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Dutch Molecular Pathology Center, Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht (Netherlands); Salvatori, Daniela C.F. [Leiden University Medical Center, Central Animal Facility, Leiden (Netherlands); Schaap, Mirjam M. [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands); Maas, Saskia [Leiden University Medical Center, Central Animal Facility, Leiden (Netherlands); Robinson, Joke; Verhoef, Aart; Benthem, Jan van; Luijten, Mirjam [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Steeg, Harry van, E-mail: Harry.van.Steeg@rivm.nl [Laboratory for Health Protection Research, National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands)

    2013-01-15

    An accurate assessment of the carcinogenic potential of chemicals and pharmaceutical drugs is essential to protect humans and the environment. Therefore, substances are extensively tested before they are marketed to the public. Currently, the rodent two-year bioassay is still routinely used to assess the carcinogenic potential of substances. However, over time it has become clear that this assay yields false positive results and also has several economic and ethical drawbacks including the use of large numbers of animals, the long duration, and the high cost. The need for a suitable alternative assay is therefore high. Previously, we have proposed the Xpa*p53 mouse model as a very suitable alternative to the two-year bioassay. We now show that the Xpc*p53 mouse model preserves all the beneficial traits of the Xpa*p53 model for sub-chronic carcinogen identification and can identify both genotoxic and non-genotoxic carcinogens. Moreover, Xpc*p53 mice appear to be more responsive than Xpa*p53 mice towards several genotoxic and non-genotoxic carcinogens. Furthermore, Xpc*p53 mice are far less sensitive than Xpa*p53 mice for the toxic activity of DNA damaging agents and as such clearly respond in a similar way as wild type mice do. These advantageous traits of the Xpc*p53 model make it a better alternative for in vivo carcinogen testing than Xpa*p53. This pilot study suggests that Xpc*p53 mice are suited for routine sub-chronic testing of both genotoxic and non-genotoxic carcinogens and as such represent a suitable alternative to possibly replace the murine life time cancer bioassay. Highlights: ► The Xpc*p53 mouse model is able to identify genotoxic and non-genotoxic carcinogens. ► Time, animals and cost can be significantly reduced compared to the 2-year bioassay. ► Xpc*p53 mice are more advantageous for carcinogen identification than Xpa*p53 mice. ► Xpc*p53 mice exhibit a wild type response upon exposure to genotoxicants.

  1. Human biological monitoring of occupational genotoxic exposures

    DEFF Research Database (Denmark)

    Knudsen, Lisbeth E.; Sorsa, M

    1993-01-01

    for and the biomonitoring results should preferentially be linked with accurate ambient air monitoring. In persons occupationally exposed to styrene the endpoints of DNA-damage and DNA-repair in genetic monitoring are methods of choice in exposure situations above the current Danish (25 ppm) or Finnish (20 ppm......) occupational exposure limit value of styrene in ambient air. The consideration of ethical issues in human genetic monitoring is an important but often overlooked aspect. This includes the scientific and preventional relevance of performing a test on individuals, pre- and post study information of donors......Human biological monitoring is a valuable tool for exposure assessment in groups of persons occupationally exposed to genotoxic agents. If the monitoring activity covers genetic material the term genetic monitoring is used. The methods used for genetic monitoring are either substance specific, e...

  2. Cytotoxicity and genotoxicity assessment of Euphorbia hirta in MCF-7 cell line model using comet assay

    Institute of Scientific and Technical Information of China (English)

    Kwan Yuet Ping; Ibrahim Darah; Yeng Chen; Sreenivasan Sasidharan

    2013-01-01

    Objective:To evaluate the cytotoxicity and genotoxicity activity of Euphorbia hirta (E. hirta) in MCF-7 cell line model using comet assay. Methods: The cytotoxicity of E. hirta extract was investigated by employing brine shrimp lethality assay and the genotoxicity of E. hirta was assessed by using Comet assay. Results: Both toxicity tests exhibited significant toxicity result. In the comet assay, the E. hirta extract exhibited genotoxicity effects against MCF-7 DNA in a time-dependent manner by increasing mean percentage of DNA damage. The extract of E. hirta showed significant toxicity against brine shrimp with an LC50 value of 620.382 μg/mL (24 h). Comparison with positive control potassium dichromate signifies that cytotoxicity exhibited by the methanol extract might have moderate activity. Conclusion:The present work confirmed the cytotoxicity and genotoxicity of E. hirta. However, the observed toxicity of E. hirta extracts needs to be confirmed in additional studies.

  3. Anti-genotoxic potential of bilirubin in vivo

    DEFF Research Database (Denmark)

    Wallner, Marlies; Antl, Nadja; Rittmannsberger, Barbara;

    2013-01-01

    The bile pigment bilirubin is a known antioxidant and is associated with protection from cancer and cardiovascular disease (CVD) when present in too strong concentrations. Unconjugated bilirubin (UCB) might also possess anti-genotoxic potential by preventing oxidative damage to DNA. Moderately...... elevated bilirubin levels are found in individuals with Gilbert syndrome and more severe in the hyperbilirubinemic Gunn rat model. This study was therefore aimed to assess the levels of oxidative damage to DNA in Gilbert syndrome subjects and Gunn rats compared to matched controls. Seventy-six individuals...

  4. Assessment of Genotoxicity of Ionizing radiation using Tradescantia-Comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Han, Min; Ryu, Tae Ho; Hyun, Kyung Man; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Wilhelmova, Nad [Institute of Experimental Botany, Prague (Czech Republic)

    2010-05-15

    Over the last two decades, several new methodologies for the detection of DNA damage have been developed. The comet assay is currently used in different areas of biological sciences to detect DNA damage. The comet assay, also called the single cell gel electrophoresis (SCGE) was first introduced by Ostling and Johanson as a microelectrophoretic technique for the direct visualization of DNA damage in individual cells. The comet assay, due to its simplicity, sensitivity and need of a few cells, is ideal as a short-term genotoxicity test. The comet assay can theoretically be applied to every type of eukaryotic cell, including plant cells. Plants are very useful as monitors of genetic effects caused by pollution in the atmosphere, water and soil. Although the genotoxic effects detected by Tradescantia tests cannot be associated with mutagenesis or even carcinogenesis in humans, these bioassays are very useful tools for screening the mutagenic potential in the environment. Experiments were conducted to study the genotoxic effects of ionizing radiations on the genome integrity, particularly of Tradescantia. The increasingly frequent use of Tradescantia as a sensitive environmental bioindicator of genotoxic effects. This study was designed to assess the genotoxicity of ionizing radiation using Tradescnatia-comet assay

  5. Recent perspectives on the relations between faecal mutagenicity, genotoxicity and diet

    Directory of Open Access Journals (Sweden)

    Silvia eGratz

    2011-03-01

    Full Text Available DNA damage is an essential component of the genesis of colonic cancer. Gut microbial products and food components are thought to be principally responsible for the damage that initiates disease progression. Modified Ames tests and Comet assays have been developed for measuring mutagenicity and genotoxicity. Their relevance to oncogenesis remains to be confirmed, as does the relative importance of different mutagenic and genotoxic compounds present in faecal water and the bacteria involved in their metabolism. Dietary intervention studies provide clues to the likely risks of oncogenesis. High-protein diets lead to increases in N-nitroso compounds in faecal water and greater DNA damage as measured by the Comet assay, for example. Other dietary interventions, such as non-digestible carbohydrates and probiotics, may lead to lower faecal genotoxicity. In order to make recommendations to the general public, we must develop a better understanding of how genotoxic compounds are formed in the colon, how accurate the Ames and Comet assays are, and how diet affects genotoxicity.

  6. Current investigations into the genotoxicity of zinc oxide and silica nanoparticles in mammalian models in vitro and in vivo: carcinogenic/genotoxic potential, relevant mechanisms and biomarkers, artifacts, and limitations

    Directory of Open Access Journals (Sweden)

    Kwon JY

    2014-12-01

    Full Text Available Jee Young Kwon,1,* Preeyaporn Koedrith,2,* Young Rok Seo1 1Department of Life Science, Institute of Environmental Medicine, Dongguk University, Seoul, Republic of Korea; 2Faculty of Environment and Resource Studies, Mahidol University, Phuttamonthon District, NakhonPathom, Thailand *These authors contributed equally to this work and should be considered as co-first authors Abstract: Engineered nanoparticles (NPs are widely used in many sectors, such as food, medicine, military, and sport, but their unique characteristics may cause deleterious health effects. Close attention is being paid to metal NP genotoxicity; however, NP genotoxic/carcinogenic effects and the underlying mechanisms remain to be elucidated. In this review, we address some metal and metal oxide NPs of interest and current genotoxicity tests in vitro and in vivo. Metal NPs can cause DNA damage such as chromosomal aberrations, DNA strand breaks, oxidative DNA damage, and mutations. We also discuss several parameters that may affect genotoxic response, including physicochemical properties, widely used assays/end point tests, and experimental conditions. Although potential biomarkers of nanogenotoxicity or carcinogenicity are suggested, inconsistent findings in the literature render results inconclusive due to a variety of factors. Advantages and limitations related to different methods for investigating genotoxicity are described, and future directions and recommendations for better understanding genotoxic potential are addressed. Keywords: carcinogenicity, exposure assessment, genotoxicity, nanoparticles, risk evaluation

  7. Nuclear PTEN controls DNA repair and sensitivity to genotoxic stress

    Science.gov (United States)

    Bassi, C; Ho, J; Srikumar, T; Dowling, RJO; Gorrini, C; Miller, SJ; Mak, TW; Neel, BG; Raught, B; Stambolic, V

    2016-01-01

    Loss of function of the Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) tumor suppressor gene is associated with many human cancers. In the cytoplasm, PTEN antagonizes the Phosphatidylinositol 3′ kinase (PI3K) signaling pathway. PTEN also accumulates in the nucleus, where its function remains poorly understood. We demonstrate that SUMOylation (SUMO) of PTEN controls its nuclear localization. In cells exposed to genotoxic stress, SUMO-PTEN was rapidly excluded from the nucleus dependent on the protein kinase Ataxia telangiectasia mutated (ATM). Cells lacking nuclear PTEN were hypersensitive to DNA damage, while PTEN-deficient cells were susceptible to killing by a combination of genotoxic stress and a small molecule PI3K inhibitor both in vitro and in vivo. Our findings may have implications for individualized therapy for patients with PTEN-deficient tumors. PMID:23888040

  8. El té verde en la quimioprevención in vivo del daño genotóxico inducido por metales cancerígenos (cromo [VI] Green tea and its role on chemoprevention in vivo of genotoxic damage induced by carcinogenic metals (Chromium [VI

    Directory of Open Access Journals (Sweden)

    M. C. García-Rodríguez

    2012-08-01

    las 72 horas, del 20 y 35% a las 48 horas y del 18 y 31% a las 24 horas con los tratamientos intragástricos y ad libitum respectivamente, en comparación con el grupo tratado solo con el trióxido de cromo. Por lo que, el té verde redujo el daño genotóxico inducido por el trióxido de cromo, y la mayor protección se presentó a las 72 horas. Conclusiones: Nuestros hallazgos muestran un efecto protector del té verde contra el daño al material genético inducido por compuestos metálicos como los del Cr [VI], sugiriendo que sus componentes antioxidantes son los que tienen un efecto quimiopreventivo sobre el EOx generado por el Cr [VI] durante su reducción a Cr [III]. El hecho de que la mayor disminución de la frecuencia de MN se observe a las 72 horas y con el tratamiento ad libitum, sugiere que el efecto protector depende de la biodisponibilidad, farmacodinámica y farmacocinética del principio activo del té verde, por lo que la administración del té verde durante tiempos más prolongados antes de la exposición con compuestos de Cr [VI] podría tener un efecto preventivo más consistente.Background: Consumption of green tea, by its antioxidant properties, has been associated with beneficial health effects, because antioxidant may play a role in the risk and pathogenesis of several chronic diseases, especially cardiovascular disease and cancer. On the other hand, it has been reported that metal compounds such as chromium [VI] are carcinogenic and can induce genotoxic damage through the Oxidative Stress. Therefore, it is possible that green tea has a protective effect against the genotoxic damage induced by this compounds. Objective: To evaluate the effect of oral administration of green tea over the genotoxic damage induced by Cr [VI] by quantification of micronucleus (MN in polychromatic erythrocytes (EPC. Materials and methods: We use mice of CD-1 strain that were randomly divided into the following groups: (i control, (ii treatment with green tea, (iii

  9. Genotoxic Effect of Chronic Exposure to DDT on Lymphocytes, Oral Mucosa and Breast Cells of Female Rats

    OpenAIRE

    Ruth De Celis; Ulises Gómez-Pinedo; Hugo Salado-Ponce; Alfredo Feria-Velasco; Alejandro Canales-Aguirre; Eduardo Padilla-Camberos

    2011-01-01

    The genotoxicity of some environmental contaminants may affect human health directly by damaging genetic material and thus plays an important role in cancer development. Xenoestrogens are one kind of environmental pollutants that may alter hormonal routes or directly affect DNA. The number of available biomarkers used to assess genetic risk and cancer is very extensive. The present study evaluated genotoxicity produced by the pesticide DDT on systemic and mammary gland cells obtained from adu...

  10. Evaluation of genotoxic responses of Chaetoceros tenuissimus and Skeletonema costatum to water accommodated fraction of petroleum hydrocarbons as biomarker of exposure

    Digital Repository Service at National Institute of Oceanography (India)

    Desai, S.R.; Verlecar, X.N.; Ansari, Z.A.; Jagtap, T.G.; Sarkar, A.; Vashistha, D.; Dalal, S.G.

    Genotoxic responses towards chronic exposure of Chaetoceros tenuissimus and Skeletonema costatum to water accommodated fraction of petroleum hydrocarbons (WAF-P) were evaluated as biomarkers of petroleum hydrocarbons pollution. The DNA damage caused...

  11. The combined bacterial Lux-Fluoro test for the detection and quantification of genotoxic and cytotoxic agents in surface water: results from the "Technical Workshop on Genotoxicity Biosensing".

    Science.gov (United States)

    Baumstark-Khan, Christa; Rabbow, Elke; Rettberg, Petra; Horneck, Gerda

    2007-12-15

    The bioassay Lux-Fluoro test was developed for the rapid detection and quantification of environmental pollutants with genotoxic and/or cytotoxic potential. This bacterial test system uses two different reporter genes whose gene products and their reactions, respectively, can be measured easily and simultaneously by optical methods. Genotoxicity is measured by the increase of bioluminescence in genetically modified bacteria which carry a plasmid with a complete lux operon for the enzyme luciferase from the marine photobacterium P. leiognathi under the control of a DNA-damage dependent so-called SOS promoter. If the deoxyribonucleic acid in these bacteria is damaged by a genotoxic chemical, the SOS promoter is turned on and the lux operon is expressed. The newly synthesized luciferase reacts immediately with its substrate thereby producing bioluminescence in a damage-proportional manner. In the second part of the system, genetically modified bacteria carry the gene for the green fluorescent protein (gfp) from the jellyfish Aequora victoria downstream from a constitutively expressed promoter. These bacteria are fluorescent under common growth conditions. If their cellular metabolism is disturbed by the action of cytotoxic chemicals, the fluorescence decreases in a dose-proportional manner. The combined Lux-Fluoro test is shown to be well suited for the biological assessment of the geno- and cytotoxicity of a series of model agents and environmental samples at the Technical Workshop on Genotoxicity Biosensing (TECHNOTOX).

  12. DNA dosimetry assessment for sunscreen genotoxic photoprotection.

    Directory of Open Access Journals (Sweden)

    André Passaglia Schuch

    Full Text Available BACKGROUND: Due to the increase of solar ultraviolet radiation (UV incidence over the last few decades, the use of sunscreen has been widely adopted for skin protection. However, considering the high efficiency of sunlight-induced DNA lesions, it is critical to improve upon the current approaches that are used to evaluate protection factors. An alternative approach to evaluate the photoprotection provided by sunscreens against daily UV radiation-induced DNA damage is provided by the systematic use of a DNA dosimeter. METHODOLOGY/PRINCIPAL FINDINGS: The Sun Protection Factor for DNA (DNA-SPF is calculated by using specific DNA repair enzymes, and it is defined as the capacity for inhibiting the generation of cyclobutane pyrimidine dimers (CPD and oxidised DNA bases compared with unprotected control samples. Five different commercial brands of sunscreen were initially evaluated, and further studies extended the analysis to include 17 other products representing various formulations and Sun Protection Factors (SPF. Overall, all of the commercial brands of SPF 30 sunscreens provided sufficient protection against simulated sunlight genotoxicity. In addition, this DNA biosensor was useful for rapidly screening the biological protection properties of the various sunscreen formulations. CONCLUSIONS/SIGNIFICANCE: The application of the DNA dosimeter is demonstrated as an alternative, complementary, and reliable method for the quantification of sunscreen photoprotection at the level of DNA damage.

  13. Genotoxic effects of starvation and dimethoate in haemocytes and midgut gland cells of wolf spider Xerolycosa nemoralis (Lycosidae).

    Science.gov (United States)

    Wilczek, Grażyna; Mędrzak, Monika; Augustyniak, Maria; Wilczek, Piotr; Stalmach, Monika

    2016-06-01

    The aim of this study was to assess the genotoxic effects of starvation and dimethoate (organophosphate insecticide) in female and male wolf spiders Xerolycosa nemoralis (Lycosidae) exposed to the stressors under laboratory conditions. DNA damage was measured in haemocytes and midgut gland cells using the comet assay. In response to the two stressing factors, both cell types showed %TDNA, tail length (TL) and OTM values higher in males than in females. Level of DNA damage in haemocytes was greater than in midgut gland cells. In both sexes, the strongest genotoxicity was recorded at single application of dimethoate. After five-time exposure to the pesticide, genotoxic effects of a single dose were sustained in males and reduced to the control level in females. Starvation stress was well tolerated by the females, in which neither cell type was affected by DNA damage. However, in male haemocytes food deprivation induced severe DNA damage, what suggests suppression of the defence potential at prolonged starvation periods.

  14. Overview of genotoxic impurities in pharmaceutical development.

    Science.gov (United States)

    Bercu, Joel P; Dobo, Krista L; Gocke, Elmar; McGovern, Timothy J

    2009-01-01

    This symposium focuses on the management of genotoxic impurities in the synthesis of pharmaceuticals. Recent developments in both Europe and United States require sponsors of new drug applications to develop processes to control the risks of potential genotoxic impurities. Genotoxic impurities represent a special case relative to the International Conference on Harmonisation Q3A/Q3B guidances, because genotoxicity tests used to qualify the drug substance may not be sufficient to demonstrate safety of a potentially genotoxic impurity. The default risk management approach for a genotoxic impurity is the threshold of toxicological concern unless a more specific risk characterization is appropriate. The symposium includes descriptions of industry examples where impurities are introduced and managed in the synthesis of a pharmaceutical. It includes recent regulatory developments such as the "staged threshold of toxicological concern" when administration is of short duration (eg, during clinical trials).

  15. Lead- induced genotoxicity in wheat

    Directory of Open Access Journals (Sweden)

    Elena Truta

    2010-02-01

    Full Text Available The changes induced in cytogenetic parameters from root meristems of Triticum aestivum cv. Maruca seedlings have been studied after treatment with lead acetate and lead nitrate solutions, at four concentrations (10, 25, 50, 100 μM containing 2.07, 5.18, 10.36, respectively 20.72 μg ml-1 Pb2+. Lead induced mitosis disturbances in root meristematic cells of wheat seedlings, expressed mainly in decrease of mitotic index and changes in preponderance of division phases. This heavy metal has genotoxic effects, expressed in the occurrence of many chromosomal aberrations in all Pb2+ treated variants. Pb2+ nitrate shows a more pronounced genotoxic potential than lead acetate trihydrate.

  16. Genotoxic and cytotoxic damage by the therapeutic radiopharmaceutical [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP as in vivo generator system; Dano genotoxico y citotoxico por el radiofarmaco terpeutico [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP como sistema de generador in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Pedraza L, M.; Piedras R, J. [Instituto Nacional de Ciencias Medicas y Nutricion, Salvador Zubiran. Vasco. de Quiroga 15, 14000 Mexico D.F. (Mexico); Ferro F, G.; Morales R, P. [ININ, Km. 36.5 Carretera Mexico-Toluca, Ocoyoacac, 52045 Estado de Mexico (Mexico); Murphy S, E. [Hospital Santaelena, Mexico D.F. (Mexico); Hernandez O, O. [Escuela Superior de Fisica y Matematicas, IPN, Mexico D.F. (Mexico)

    2005-07-01

    In patients with leukemias and multiple myeloma, the cure can be obtained to inclination of a bone marrow transplant (m.o.), for that which one is used a combination of external radiotherapy and chemotherapy with the consequent toxicity to healthy organs. The complex [{sup 166}Dy]Dy/{sup 166}Ho-ethylenediaminetetramethylenephosphonate ([{sup 166}Dy]Dy/{sup 166}Ho-EDTMP) it forms a generator system in vivo stable with bony selective likeness in mice therefore, this it could work as a therapeutic radiopharmaceutical for bone marrow ablation. The objective of this original work was to determine the genotoxic and cytotoxic damage produced by the [{sup 166}Dy]Dy/{sup 166}Ho-EDTMP like a generator system in vivo by means of the reticulocytes reduction (RET) and micronucleus elevation in reticulocytes (RET-MN) in peripheral blood and to evaluate its myeloablative potential for histopathologic studies. It was irradiated {sup 166}Dy{sub 2}O{sub 3} enriched and it was add in form {sup 166}DyCI{sub 3} to the EDTMP in a softening media of phosphates (pH 8), the optimal molar relationship {sup 166}Dy: EDTMP was 1.7:1 and the radiochemical purity was evaluated by ITLC. The Dy:EDTMP complexes, non radioactive, its were prepared in the same way with non irradiated dysprosium oxide. A group of BALB/c mice was injected intraperitoneally with the radiopharmaceutical and two groups of control mice were injected with the non radioactive complex and with sodium chloride 0.9% respectively. Before injecting each one of the solutions it was take a basal sample of peripheral blood of the mouse tail and each 48 h post-injection during 12 d. The animals were sacrificed to obtain the organs of interest and to determine the radioactivity in each one. The femur was used for the histopathologic studies. The quantification of the frequency of RET and RET-MN was carried out by flow cytometry of the sanguine samples and the Monte Carlo code MCNP4B for the dosimetry calculations was used. The

  17. Ogg1 genetic background determines the genotoxic potential of environmentally relevant arsenic exposures.

    Science.gov (United States)

    Bach, Jordi; Sampayo-Reyes, Adriana; Marcos, Ricard; Hernández, Alba

    2014-03-01

    Inorganic arsenic (i-As) is a well-established human carcinogen to which millions of people are exposed worldwide. It is generally accepted that the genotoxic effects of i-As after an acute exposure are partially linked to the i-As-induced production of reactive oxygen species, but it is necessary to better determine whether chronic sub-toxic i-As doses are able to induce biologically significant levels of oxidative DNA damage (ODD). To fill in this gap, we have tested the genotoxic and oxidative effects of environmentally relevant arsenic exposures using mouse embryonic fibroblast MEF mutant Ogg1 cells and their wild-type counterparts. Effects were examined by using the comet assay complemented with the use of FPG enzyme. Our findings indicate that MEF Ogg1-/- cells are more sensitive to arsenite-induced acute toxicity, genotoxicity and ODD. Long-term exposure to sub-toxic doses of arsenite generates a detectable increase in ODD and genotoxic DNA damage only in MEF Ogg1-deficient cells. Altogether, the data presented here point out the relevance of ODD and Ogg1 genetic background on the genotoxic risk of i-As at environmentally plausible doses. The persistent accumulation of DNA 8-OH-dG lesions in Ogg1-/- cells during the complete course of the exposure suggests a relevant role in arsenic-associated carcinogenic risk in turn.

  18. Evolution of genotoxicity test methods in Japan.

    Science.gov (United States)

    Sofuni, Toshio

    2017-01-01

    The evolution of methods to assess genotoxicity of test compounds is thought to be one of the important subjects in The Japanese Environmental and Mutagen Society (JEMS). In 1970, the Ministry of Education of Japan (at that time) organized a research group (Organizer: Y. Tazima, National Institute of Genetics), and started a systematic research on the genotoxic effects induced by chemical substances. Considering the importance of this issue through the outcomes of the research group, JEMS was established in 1972, and President Tazima organized the 1st annual meeting in the August in Tokyo with the participation of experts in this field working in national institutes, universities and others in Japan. The discovery that food additives possessed genotoxic potential triggered various scientific activities in the field of genotoxicity. Another important point was the correlation between genotoxicity and carcinogenicity, in which the establishment of the reverse mutation assay played an important role. Other critical factors, such as side effects of drugs, occupational cancer, and environmental pollution due to genotoxic chemicals, emphasized the importance of genotoxicity tests for human safety. The tests performed to assess genotoxicity from 1960s to 1980s will be described to understand that many different genotoxic methodologies were discussed in these periods.

  19. Genotoxicity evaluation of drinking water sources in human peripheral blood lymphocytes using the comet assay

    Institute of Scientific and Technical Information of China (English)

    WU Yulin; CHEN Haigang; LI Zhaoli; SUN Liwei; QU Mengmeng; LI Mei; KONG Zhiming

    2008-01-01

    The potential harm of organic pollutants in drinking water to human health is widely focused on in the world; more and more pollutants with genotoxic substances are released into the aquatic environment. Water source samples were collected from 7 different localities of Nanjing City. The potential genotoxicity of organic extracts from drinking water sources were investigated by means of the comet assay in human peripheral lymphocytes. The results showed that all the organic extracts from all the water source samples could induce DNA damages of human peripheral blood lymphocytes at different levels. A significant difference (P < 0.01) was observed when compared with the solvent control. The DNA damage increased with the increase of the dosage of the original water source. Significant differences of DNA damage were observed in different drinking water sources, as shown by the multiple comparisons analysis at the dosage of 100×; the degree of DNA damage treated by Hushu waterworks (at town level) was the most serious, the arbitrary units (AU) was 141.62±6.96, however, that of Shangyuanmen waterworks (at city level) was only 109.64±2.97. The analysis also revealed that the genotoxicity of town's water sources was higher than that of the city. The results demonstrated that the comet assay can be successfully applied to the genotoxicity monitoring programs of drinking water sources.

  20. Genotoxicity assessment of amaranth and allura red using Saccharomyces cerevisiae.

    Science.gov (United States)

    Jabeen, Hafiza Sumara; ur Rahman, Sajjad; Mahmood, Shahid; Anwer, Sadaf

    2013-01-01

    Amaranth (E123) and Allura red (E129), very important food azo dyes used in food, drug, paper, cosmetic and textile industries, were assessed for their genotoxic potential through comet assay in yeast cells. Comet assay was standardized by with different concentration of H(2)O(2). Concentrations of Amaranth and Allura red were maintained in sorbitol buffer starting from 9.76 to 5,000 μg/mL and 1 × 10(4) cells were incubated at two different incubation temperatures 28 and 37°C. Amaranth (E123) and Allura red (E129) were found to exhibit their genotoxic effect directly in Saccharomyces cerevisiae. No significant genotoxic activity was observed for Amaranth and Allura red at 28°C but at 37°C direct relation of Amaranth concentration with comet tail was significant and no positive relation was seen with time exposure factor. At 37°C the minimum concentration of Amaranth and Allura red at which significant DNA damage observed through comet assay was 1,250 μg/mL in 2nd h post exposure time. The results indicated that food colors should be carefully used in baking products as heavy concentration of food colors could affect the fermentation process of baking.

  1. Genotoxic and apoptotic effects of Goeckerman therapy for psoriasis

    Energy Technology Data Exchange (ETDEWEB)

    Borska, L.; Andrys, C.; Krejsek, J.; Hamakova, K.; Kremlacek, J.; Palicka, V.; Ranna, D.; Fiala, Z. [Charles University Prague, Prague (Czech Republic). Faculty of Medicine

    2010-03-15

    Goeckerman therapy (GT) for psoriasis is based on cutaneous application of crude coal tar (polycyclic aromatic hydrocarbons (PAH)) and exposure to ultraviolet radiation (UVR). PAH and UVR are mutagenic, carcinogenic and immunotoxic agents that promote apoptosis. We evaluated dermal absorption of PAH as well as the genotoxic and apoptotic effects of GT in 20 patients with psoriasis, by determining numbers of chromosomal abnormalities in peripheral lymphocytes, and levels of 1-hydroxypyrene (1-OHP), p53 protein and soluble FasL (sFasL) in urine and/or blood, before and after GT. Psoriasis Area and Severity Index (PASI) score was used to evaluate clinical efficacy of GT. Compared with pre-treatment levels, there was a significant increase in urine 1-OHP, indicating a high degree of dermal absorption of PAH (P <0.01). We also found a significant increase in the number of chromosomal abnormalities in peripheral blood lymphocytes (P <0.001), suggesting that GT is genotoxic; significantly increased p53 protein in plasma (P <0.05), an indicator of cell response to DNA damage; and significantly increased sFasL in serum (P <0.01), an indicator of apoptosis. The PASI score was significantly decreased after GT (P <0.001), confirming clinical benefit of this treatment. Our results demonstrate high dermal absorption of PAH during GT and provide evidence that GT promotes genotoxicity and apoptosis.

  2. Neurobehavioral and genotoxic evaluation of (-)-linalool in mice.

    Science.gov (United States)

    Coelho, Vanessa; Mazzardo-Martins, Leidiane; Martins, Daniel Fernandes; Santos, Adair Roberto Soares; da Silva Brum, Lucimar Filot; Picada, Jaqueline Nascimento; Pereira, Patrícia

    2013-10-01

    (-)-Linalool is a monoterpene compound commonly found as a major component of the essential oil of several aromatic species. It has been shown to exert several actions in the central nervous system (CNS) and is able to inhibit glutamate receptors. This study investigated the effect of (-)-linalool in depression and genotoxicity models. Mice were given (-)-linalool (10, 50, 100 or 200 mg/kg i.p.) and were evaluated using the tail suspension test (TST). Genotoxic and antigenotoxic effects in blood and brain were investigated using the alkaline comet assay. In the TST, the animals that received doses of 100 and 200 mg/kg presented a decrease in immobility times. No increase in DNA damage was observed in either tissue, and resistance to DNA oxidative damage induced by hydrogen peroxide did not increase. (-)-Linalool showed an antidepressant-like activity in the TST and was unable to cause damage/protection to DNA in brain tissue and peripheral blood. This investigation provides evidence of an important effect of (-)-linalool on the CNS; however, more studies are necessary to support its possible clinical uses.

  3. Nanoceria have no genotoxic effect on human lens epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Pierscionek, Barbara K; Yasseen, Akeel A [School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA (United Kingdom); Li, Yuebin; Schachar, Ronald A; Chen, Wei [Department of Physics, University of Texas at Arlington, Arlington, TX 76019 (United States); Colhoun, Liza M, E-mail: b.pierscionek@ulster.ac.uk, E-mail: weichen@uta.edu [Centre for Vision and Vascular Sciences, School of Medicine, Dentistry and Biomedical Sciences, Queen' s University Belfast, Grosvenor Road, Belfast, BT12 6BA (United Kingdom)

    2010-01-22

    There are no treatments for reversing or halting cataract, a disease of the structural proteins in the eye lens, that has associations with other age-related degenerative conditions such as Alzheimer's disease. The incidence of cataract and associated conditions is increasing as the average age of the population rises. Protein folding diseases are difficult to assess in vivo as proteins and their age-related changes are assessed after extraction. Nanotechnology can be used to investigate protein changes in the intact lens as well as for a potential means of drug delivery. Nanoparticles, such as cerium oxide (CeO{sub 2}) which have antioxidant properties, may even be used as a means of treating cataract directly. Prior to use in treatments, nanoparticle genotoxicity must be tested to assess the extent of any DNA or chromosomal damage. Sister chromatid exchanges were measured and DNA damage investigated using the alkaline COMET assay on cultured human lens epithelial cells, exposed to 5 and 10 {mu}g ml{sup -1} of CeO{sub 2} nanoparticles (nanoceria). Nanoceria at these dosages did not cause any DNA damage or significant increases in the number of sister chromatid exchanges. The absence of genotoxic effects on lens cells suggests that nanoceria, in the doses and exposures tested in this study, are not deleterious to the eye lens and have the potential for use in studying structural alterations, in developing non-surgical cataract treatments and in investigating other protein folding diseases.

  4. In vivo genotoxicity assessment of acrylamide and glycidyl methacrylate.

    Science.gov (United States)

    Dobrovolsky, Vasily N; Pacheco-Martinez, M Monserrat; McDaniel, L Patrice; Pearce, Mason G; Ding, Wei

    2016-01-01

    Acrylamide (ACR) and glycidyl methacrylate (GMA) are structurally related compounds used for making polymers with various properties. Both chemicals can be present in food either as a byproduct of processing or a constituent of packaging. We performed a comprehensive evaluation of ACR and GMA genotoxicity in Fisher 344 rats using repeated gavage administrations. Clastogenicity was measured by scoring micronucleated (MN) erythrocytes from peripheral blood, DNA damage in liver, bone marrow and kidneys was measured using the Comet assay, and gene mutation was measured using the red blood cell (RBC) and reticulocyte Pig-a assay. A limited histopathology evaluation was performed in order to determine levels of cytotoxicity. Doses of up to 20 mg/kg/day of ACR and up to 250 mg/kg/day of GMA were used. ACR treatment resulted in DNA damage in the liver, but not in the bone marrow. While ACR was not a clastogen, it was a weak (equivocal) mutagen in the cells of bone marrow. GMA caused DNA damage in the cells of bone marrow, liver and kidney, and induced MN reticulocytes and Pig-a mutant RBCs in a dose-dependent manner. Collectively, our data suggest that both compounds are in vivo genotoxins, but the genotoxicity of ACR is tissue specific.

  5. Genotoxic effects in wild rodents (Rattus rattus and Mus musculus) in an open coal mining area.

    Science.gov (United States)

    León, Grethel; Pérez, Lyda Espitia; Linares, Juan Carlos; Hartmann, Andreas; Quintana, Milton

    2007-06-15

    Coal is a mixture of a variety of compounds containing mutagenic and carcinogenic polycyclic aromatic hydrocarbons. Exposure to coal is considered as an important non-cellular and cellular source of reactive oxygen species that can induce DNA damage. In addition, spontaneous combustion can occur in coal mining areas, further releasing compounds with detrimental effects on the environment. In this study the comet assay was used to investigate potential genotoxic effects of coal mining activities in peripheral blood cells of the wild rodents Rattus rattus and Mus musculus. The study was conducted in a coal mining area of the Municipio de Puerto Libertador, South West of the Departamento de Cordoba, Colombia. Animals from two areas in the coal mining zone and a control area located in the Municipio de Lorica were investigated. The results showed evidence that exposure to coal results in elevated primary DNA lesions in blood cells of rodents. Three different parameters for DNA damage were assessed, namely, DNA damage index, migration length and percentage damaged cells. All parameters showed statistically significantly higher values in mice and rats from the coal mining area in comparison to the animals from the control area. The parameter "DNA Damage Index" was found to be most sensitive and to best indicate a genotoxic hazard. Both species investigated were shown to be sensitive indicators of environmental genotoxicity caused by coal mining activities. In summary, our study constitutes the first investigation of potential genotoxic effects of open coal mining carried out in Puerto Libertador. The investigations provide a guide for measures to evaluate genotoxic hazards, thereby contributing to the development of appropriate measures and regulations for more careful operations during coal mining.

  6. Genotoxicity and Mutagenicity of Suspended Particulate Matter of River Water and Waste Water Samples

    Directory of Open Access Journals (Sweden)

    Georg Reifferscheid

    2002-01-01

    Full Text Available Suspended particulate matter of samples of river water and waste water treatment plants was tested for genotoxicity and mutagenicity using the standardized umu assay and two versions of the Ames microsuspension assay. The study tries to determine the entire DNA-damaging potential of the water samples and the distribution of DNA-damaging substances among the liquid phase and solid phase. Responsiveness and sensitivity of the bioassays are compared.

  7. Genotoxicity of industrial wastes and effluents.

    Science.gov (United States)

    Claxton, L D; Houk, V S; Hughes, T J

    1998-06-01

    In excess of several million pounds of genotoxic and/or carcinogenic industrial wastes are released into the U.S. environment each year. Chemical characterization of these waste materials can rarely provide an adequate assessment of their genotoxicity and potential hazard. Bioassays do not require prior information about chemical composition and can effectively assess the genotoxicity of complex waste materials. The most commonly used genotoxicity assay has been the Salmonella mutagenicity assay. Results with this system have shown that the genotoxic potency of industrial wastes can vary over 10 orders of magnitude, from virtually nondetectable to highly potent. Industries employing similar industrial processes generally release wastes of similar potency. Extremely high potency wastes include those from furazolidone and nitrofurfural production. Pulp and paper mills, steel foundries, and organic chemical manufacturing facilities also discharge wastes of noteworthy potency. Treatment and remediation of some wastes, such as pulp and paper mill effluents, have been shown to reduce or eliminate genotoxicity. However, in other cases, treatment and remediation have been shown to enhance genotoxicity, such as for fungal treatment of oils. Analyses of samples collected from areas known to receive industrial wastes and effluents have shown that genotoxins can accumulate in the receiving environment and have adverse effects on indigenous biota. The evaluation of hazardous wastes and effluents by genotoxicity assays may provide data useful not only for hazard identification but for comparative risk assessment.

  8. Therapeutic efficacies of Coriandrum sativum aqueous extract against metronidazole-induced genotoxicity in Channa punctatus peripheral erythrocytes.

    Science.gov (United States)

    Talapatra, Soumendra Nath; Dasgupta, Subham; Guha, Gunjan; Auddy, Moumita; Mukhopadhyay, Aniruddha

    2010-12-01

    Metronidazole (MTZ), a nitroimidazole drug, is primarily used as an anti-protozoan or an anti-bacterial agent in humans, although its genotoxic and carcinogenic effects have been widely reported, particularly in aquatic organisms. MTZ may induce DNA damages through single-strand breaks, modification of bases, DNA-DNA and DNA-protein cross-links, ultimately leading to apoptosis or necrosis. Here, we have assessed the genotoxicity of MTZ in the peripheral erythrocytes of Channa punctatus, using micronucleation (MN) and binucleation (BN) as genotoxicity markers. The therapeutic potential of aqueous extract of Coriandrum sativum against MTZ-induced genotoxicity has also been examined. The results show significant (Psativum leaf extract. Hence, we establish that MTZ can produce considerable degrees of micronucleus and binucleus formation in peripheral erythrocytes of C. punctatus, and such deleterious effect of MTZ treatment can be mitigated by aqueous extract of C. sativum leaves.

  9. Genotoxicity evaluation of dimethoate to experimental mice by micronucleus, chromosome aberration tests, and comet assay.

    Science.gov (United States)

    Ayed-Boussema, Imen; Rjiba, Karima; Mnasri, Nourhène; Moussa, Amal; Bacha, Hassen

    2012-01-01

    Dimethoate (DM) is an organophosphate insecticide with numerous uses on field and agricultural crops and ornamentals. Data concerning DM-acute genotoxicity are controversial and knowledge on its delayed effect is limited. For this reason, we aimed to further explore DM genotoxicity resulting from subchronic intoxication of experimental mice. Thus, DM was administered to mice at doses ranging from 1 to 30 mg/kg body weight for a period of 30 consecutive days. There was a significant increase (P < .05) in the frequency of micronucleated bone marrow cells following DM administration. Furthermore, the chromosome aberration assay revealed a significant increase in the percentage of chromosome abnormalities in a dose-dependent manner. Dimethoate was also found to induce significant DNA damage in mouse bone marrow cells as assessed by the comet assay. Altogether, our results showed that, after a subchronic exposure, DM was a genotoxic compound in experimental mice.

  10. The Food Contaminant Deoxynivalenol Exacerbates the Genotoxicity of Gut Microbiota

    Science.gov (United States)

    Payros, Delphine; Martin, Patricia; Secher, Thomas; Bracarense, Ana Paula F. L.; Boury, Michèle; Laffitte, Joelle; Pinton, Philippe; Oswald, Eric

    2017-01-01

    ABSTRACT An increasing number of human beings from developed countries are colonized by Escherichia coli strains producing colibactin, a genotoxin suspected to be associated with the development of colorectal cancers. Deoxynivalenol (DON) is the most prevalent mycotoxin that contaminates staple food—especially cereal products—in Europe and North America. This study investigates the effect of the food contaminant DON on the genotoxicity of the E. coli strains producing colibactin. In vitro, intestinal epithelial cells were coexposed to DON and E. coli producing colibactin. In vivo, newborn rats colonized at birth with E. coli producing colibactin were fed a DON-contaminated diet. Intestinal DNA damage was estimated by the phosphorylation of histone H2AX. DON exacerbates the genotoxicity of the E. coli producing colibactin in a time- and dose-dependent manner in vitro. Although DON had no effect on the composition of the gut microbiota, and especially on the number of E. coli, a significant increase in DNA damage was observed in intestinal epithelial cells of animals colonized by E. coli strains producing colibactin and coexposed to DON compared to animals colonized with E. coli strains unable to produce colibactin or animals exposed only to DON. In conclusion, our data demonstrate that the genotoxicity of E. coli strains producing colibactin, increasingly present in the microbiota of asymptomatic human beings, is modulated by the presence of DON in the diet. This raises questions about the synergism between food contaminants and gut microbiota with regard to intestinal carcinogenesis. PMID:28292979

  11. Genotoxic effect of Phenanthrene on Chironomus sancticaroli (Diptera: Chironomidae

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    Gisele dos Santos Morais

    2014-08-01

    Full Text Available Phenanthrene, a Polycyclic Aromatic Hydrocarbon, remains adsorbed to sedimentary particles in aquatic environments. It affects mainly benthic organisms, and is considered potentially genotoxic. In ecotoxicology, species of Chironomus Meigen, 1803 are widely known as bioindicators of the effects of chemicals on aquatic organisms. This study investigates the effects of phenanthrene on the size of the head capsule of Chironomus sancticaroli Strixino & Strixino, 1981 larvae after chronic (eight days exposure, and DNA damage after acute (96 hours and chronic exposure (eight days, under laboratory conditions. DNA damage, evaluated using the alkaline comet assay, detected effects for both exposure periods, indicating that phenanthrene is toxic for C. sancticaroli. For the acute exposure, we analyzed five concentrations of phenanthrene, between 0.16 mg.l-1 and 1.60 mg.l-1, detecting significant differences (Kruskall-Wallis test with p < 0.05 in the degree of DNA damage in all groups. These effects were not dose-dependent. For the chronic exposure, two concentrations (0.16 mg.l-1, 0.83 mg.l-1 were analyzed, and DNA damage was observed in both. Again, the effects were not dose-dependent. This indicates that phenanthrene is genotoxic to larvae of C. sancticaroli even at low concentrations. The size of the head capsule was evaluated after chronic exposure to concentrations of 0.16 mg.l-1 and 0.83 mg.l-1. Significant differences (ANOVA test with p < 0.05 were detected in the two concentrations, and a reduction in the size of the larval head capsule was observed. This suggests that phenanthrene causes delay in larval development. These results indicate that phenanthrene affects the development of and causes DNA damage in C. sancticaroli larvae. Therefore, we suggest that C. sancticaroli can be used as a biological indicator for environmental contamination with phenanthrene.

  12. Mutagenic and genotoxic activity of particulate matter MP2,5, in Pamplona, North Santander, Colombia

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    Martínez Montañez, Mónica Liseth

    2012-10-01

    Full Text Available Objective: To study the mutagenic and genotoxic activities of particulate material (MP2,5 collected in Pamplona, Norte de Santander, Colombia.Materials and methods: MP2,5 was monitored by means of a Partisol 2025 sequential air sampler with Plus Palmflex quartz filters. The latter were subjected to two extraction procedures: Soxhlet extraction using dichloromethane-acetone; and ultrasonic extraction using dichloromethane, acetone and dichloromethane/ acetone mix. The mutagenic and genotoxic activities were determined for each extract.Results: This is the first study conducted in Colombia that reports the mutagenic and genotoxic activities associated with particulate matter (MP2,5 taken from vehicular emissions in Pamplona, Norte de Santander. The mutagenic assay determined by the Ames test using Salmonella typhimurium strains TA98 and TA100 showed a high direct mutagenic activity in the analyzed extracts. On the other hand, the genotoxic activity, determined by means of the comet assay, was high too.Conclusion: Particulate material (MP2,5 present in air samples in Pamplona (northeastern Colombia is a risk factor for the exposed population because it can directly induce mutations and also cause genotoxic damage.

  13. High throughput comet assay to study genotoxicity of nanomaterials

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    Naouale El Yamani

    2015-06-01

    per slide. Subsequent incubation with FPG revealed damage not seen with the basic assay for strand breaks (without FPG (Harris et al., 2015. Statistical evaluation showed that oleic acid coated Fe3O4 and TiO2 NMs are genotoxic, in the experimental conditions used. No differences were seen between cell lines representing a range of different tissues – demonstrating the general usefulness of in vitro models and the ability of cells to classify NMs as genotoxic and non-genotoxic (Cowie et al., 2015. We are currently studying the effects of 20 NMs in the NANoREG project using A549, BEAS B2 and TK6 cells - again demonstrating the usefulness of the HTP comet assay for nanogenotoxicity testing.

  14. Pb low doses induced genotoxicity in Lactuca sativa plants.

    Science.gov (United States)

    Silva, S; Silva, P; Oliveira, H; Gaivão, I; Matos, M; Pinto-Carnide, O; Santos, C

    2017-03-01

    Soil and water contamination by lead (Pb) remains a topic of great concern, particularly regarding crop production. The admissible Pb values in irrigation water in several countries range from ≈0.1 to ≈5 mg L(-1). In order to evaluate putative effects of Pb within legal doses on crops growth, we exposed Lactuca sativa seeds and seedlings to increasing doses of Pb(NO3)2 up to 20 mg L(-1). The OECD parameter seed germination and seedling/plant growth were not affected by any of the Pb-concentrations used. However, for doses higher than 5 mg L(-1) significant DNA damage was detected: Comet assay detected DNA fragmentation at ≥ 5 mg L(-1) and presence of micronuclei (MN) were detected for 20 mg L(-1). Also, cell cycle impairment was observed for doses as low as 0.05 mg L(-1) and 0.5 mg L(-1) (mostly G2 arrest). Our data show that for the low doses of Pb used, the OECD endpoints were not able to detect toxicity, while more sensitive endpoints (related with DNA damage and mitotic/interphase disorders) identified genotoxic and cytostatic effects. Furthermore, the nature of the genotoxic effect was dependent on the concentration. Finally, we recommend that MN test and the comet assay should be included as sensitive endpoints in (eco)toxicological assays.

  15. Evaluation of environmental genotoxicity by comet assay in Columba livia.

    Science.gov (United States)

    González-Acevedo, Anahi; García-Salas, Juan A; Gosálvez, Jaime; Fernández, José Luis; Dávila-Rodríguez, Martha I; Cerda-Flores, Ricardo M; Méndez-López, Luis F; Cortés-Gutiérrez, Elva I

    2016-01-01

    The concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. The biomonitoring of environmental genotoxicity requires the selection of representative organisms as "sentinels," as well as the development of suitable and sensitive assays, such as those aimed at assessing DNA damage. The aim of this study was to evaluate DNA damage levels in erythrocytes from Columba livia living in the metropolitan area of Monterrey, Mexico, compared with control animals via comet assay, and to confirm the results via Micronuclei test (MN) and DNA breakage detection-fluorescence in situ hybridization (DBD-FISH). Our results showed a significant increase in DNA migration in animals from the area assayed compared with that observed in control animals sampled in non-contaminated areas. These results were confirmed by MN test and DBD-FISH. In conclusion, these observations confirm that the examination of erythrocytes from Columba livia via alkaline comet assay provides a sensitive and reliable end point for the detection of environmental genotoxicants.

  16. Early Genotoxic and Cytotoxic Effects of the Toxic Dinoflagellate Prorocentrum lima in the Mussel Mytilus galloprovincialis

    Science.gov (United States)

    Prego-Faraldo, María Verónica; Valdiglesias, Vanessa; Laffon, Blanca; Mendez, Josefina; Eirin-Lopez, Jose M.

    2016-01-01

    Okadaic acid (OA) and dinophysistoxins (DTXs) are the main toxins responsible for diarrhetic shellfish poisoning (DSP) intoxications during harmful algal blooms (HABs). Although the genotoxic and cytotoxic responses to OA have been evaluated in vitro, the in vivo effects of these toxins have not yet been fully explored. The present work fills this gap by evaluating the in vivo effects of the exposure to the DSP-toxin-producing dinoflagellate Prorocentrum lima during the simulation of an early HAB episode in the mussel Mytilus galloprovincialis. The obtained results revealed that in vivo exposure to this toxic microalgae induced early genotoxicity in hemocytes, as a consequence of oxidative DNA damage. In addition, the DNA damage observed in gill cells seems to be mainly influenced by exposure time and P. lima concentration, similarly to the case of the oxidative damage found in hemocytes exposed in vitro to OA. In both cell types, the absence of DNA damage at low toxin concentrations is consistent with the notion suggesting that this level of toxicity does not disturb the antioxidant balance. Lastly, in vivo exposure to growing P. lima cell densities increased apoptosis but not necrosis, probably due to the presence of a high number of protein apoptosis inhibitors in molluscs. Overall, this work sheds light into the in vivo genotoxic and cytotoxic effects of P. lima. In doing so, it also demonstrates for the first time the potential of the modified (OGG1) comet assay for assessing oxidative DNA damage caused by marine toxins in marine invertebrates. PMID:27231936

  17. Early Genotoxic and Cytotoxic Effects of the Toxic Dinoflagellate Prorocentrum lima in the Mussel Mytilus galloprovincialis

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    María Verónica Prego-Faraldo

    2016-05-01

    Full Text Available Okadaic acid (OA and dinophysistoxins (DTXs are the main toxins responsible for diarrhetic shellfish poisoning (DSP intoxications during harmful algal blooms (HABs. Although the genotoxic and cytotoxic responses to OA have been evaluated in vitro, the in vivo effects of these toxins have not yet been fully explored. The present work fills this gap by evaluating the in vivo effects of the exposure to the DSP-toxin-producing dinoflagellate Prorocentrum lima during the simulation of an early HAB episode in the mussel Mytilus galloprovincialis. The obtained results revealed that in vivo exposure to this toxic microalgae induced early genotoxicity in hemocytes, as a consequence of oxidative DNA damage. In addition, the DNA damage observed in gill cells seems to be mainly influenced by exposure time and P. lima concentration, similarly to the case of the oxidative damage found in hemocytes exposed in vitro to OA. In both cell types, the absence of DNA damage at low toxin concentrations is consistent with the notion suggesting that this level of toxicity does not disturb the antioxidant balance. Lastly, in vivo exposure to growing P. lima cell densities increased apoptosis but not necrosis, probably due to the presence of a high number of protein apoptosis inhibitors in molluscs. Overall, this work sheds light into the in vivo genotoxic and cytotoxic effects of P. lima. In doing so, it also demonstrates for the first time the potential of the modified (OGG1 comet assay for assessing oxidative DNA damage caused by marine toxins in marine invertebrates.

  18. Human Genotoxic Study Carried Out Two Years after Oil Exposure during the Clean-up Activities Using Two Different Biomarkers

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    Gloria Biern

    2015-11-01

    Full Text Available Micronuclei, comet and chromosome alterations assays are the most widely used biomarkers for determining the genotoxic damage in a population exposed to genotoxic chemicals. While chromosome alterations are an excellent biomarker to detect short- and long-term genotoxic effects, the comet assay only measures early biological effects, and furthermore it is unknown whether nuclear abnormalies, such as those measured in the micronucleus test, remain detectable long-term after an acute exposure. In our previous study, an increase in structural chromosome alterations in fishermen involved in the clean-up of the Prestige oil spill, two years after acute exposure, was detected. The aim of this study is to investigate whether, in lymphocytes from peripheral blood, the nuclear abnormalies (micronucleus, nucleoplasmic bridges and nuclear buds have a similar sensitivity to the chromosome damage analysis for genotoxic detection two years after oil exposure in the same non-smoker individuals and in the same peripheral blood extraction. No significant differences in nuclear abnormalies frequencies between exposed and non-exposed individuals were found (p > 0.05. However, chromosome damage, in the same individuals, was higher in exposed vs. non-exposed individuals, especially for chromosome lesions (p < 0.05. These findings, despite the small sample size, suggest that nuclear abnormalities are probably less-successful biomarkers than are chromosome alterations to evaluate genotoxic effects two or more years after an exposure to oil. Due to the great advantage of micronucleus automatic determination, which allows for a rapid study of hundreds of individuals exposed to genotoxic chemical exposure, further studies are needed to confirm whether this assay is or is not useful in long-term genotoxic studies after the toxic agent is no longer present.

  19. Using DNA damage to monitor water environment

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    DNA damage of aquatic organisms living in polluted environments can be used as a biomarker of the genotoxicity of toxic agents to organisms. This technique has been playing an important role in ecotoxicological study and environmental risk assessment. In this article, main types of DNA damage caused by pollutants in water environments were reviewed; methods of detecting DNA damage were also documented for water environmental monitoring.

  20. Potentially harmful elements in house dust from Estarreja, Portugal: characterization and genotoxicity of the bioaccessible fraction.

    Science.gov (United States)

    Plumejeaud, Sophie; Reis, Amelia Paula; Tassistro, Virginie; Patinha, Carla; Noack, Yves; Orsière, Thierry

    2016-10-22

    Due to their behavioral characteristics, young children are vulnerable to the ingestion of indoor dust, often contaminated with chemicals that are potentially harmful. Exposure to potentially harmful elements (PHEs) is currently exacerbated by their widespread use in several industrial, agricultural, domestic and technological applications. PHEs cause adverse health effects on immune and nervous systems and can lead to cancer development via genotoxic mechanisms. The present study is an integrated approach that aims at assessing the genotoxicity of bioaccessible PHEs following ingestion of contaminated house dust. A multidisciplinary methodology associating chemical characterization of five house dust samples, extraction of the bioaccessible PHEs in gastric extracts by the unified BARGE method, determination of the bioaccessible fraction and in vitro genotoxicity of gastric extracts in adenocarcinoma gastric human (AGS) cells was developed. The five gastric extracts induced dose-dependent genotoxicity in AGS cells. Copper (bioaccessible concentration up to 111 mg/kg) was probably the prevalent PHE inducing primary DNA damage (up to 5.1-fold increase in tail DNA at 0.53 g/l of gastric extract). Lead (bioaccessible concentration up to 245 mg/kg) was the most prevalent PHE inducing chromosome-damaging effects (r = 0.55; p health risks.

  1. In vitro analysis of the phytotoxic and genotoxic potential of Aligarh wastewater and Mathura refinery wastewater

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    Naveed Ahmad Fazili

    2014-01-01

    Full Text Available Present report deals with the phytotoxicity and genotoxicity of Mathura refinery wastewater and Aligarh wastewater of Northern India. The IC50 value in Allium cepa root growth inhibition test was recorded to be 0.14X and 0.10X for Mathura refinery and Aligarh industrial wastewaters, respectively. Significant decline in the survival of various Escherichia coli K12 DNA repair defective mutants was observed when the tester strains were exposed to the aforementioned samples. The order of sensitivity was invariably as: AB1157 (wild type < AB2494 (lexA mutant < AB2463 (recA mutant < AB2480 (uvrA recA double mutant. These results suggested a significant amount of DNA damage within the bacterial cells exposed to test wastewaters. A. cepa genotoxicity test also demonstrated a considerable amount of chromosomal damage of A. cepa brought about by the test samples. The aberration index (A.I. for Aligarh wastewater and refinery wastewater was recorded to be 11.2% and 14.7%, respectively, whereas the aquaguard mineral water serving as negative control displayed the A.I. value to be 2.6%. Interestingly, genotoxicity of both industrial wastewaters was reduced to a remarkable extent in presence of mannitol, the hydroxyl radical scavenger. Present study clearly indicated a distinct pattern of the chromosomal aberrations showing predominantly stickiness and stray chromosomes in case of AWW while clumping and stickiness in case of RWW, thereby affirming the genotoxicity of both test waters.

  2. Genotoxicity detected in wild mice living in a highly polluted wetland area in south western Spain

    Energy Technology Data Exchange (ETDEWEB)

    Mateos, Santiago; Daza, Paula; Dominguez, Inmaculada; Cardenas, Jose Antonio [University of Seville, Department of Cell Biology, Faculty of Biology, Avenida de la Reina Mercedes no 6, E-41012 Seville (Spain); Cortes, Felipe [University of Seville, Department of Cell Biology, Faculty of Biology, Avenida de la Reina Mercedes no 6, E-41012 Seville (Spain)], E-mail: cortes@us.es

    2008-06-15

    A field study was carried out in the south of the Iberian Peninsula in an industrial area in the neighbourhood of Huelva city, SW Spain, and in a natural area (Donana National Park) for comparison, to estimate the genetic risk induced by environmental pollution in wild mice. Genotoxic effects in a sentinel organism, the Algerian mice (Mus spretus) free living in the industrial area were compared with animals of the same species living in the natural protected area. The single cell gel electrophoresis, or Comet assay, was performed as a genotoxicity test in peripheral blood of mice. Our results clearly show that mice free living in the contaminated area bear a high burden of genetic damage as compared with control individuals. The results suggest that the assessing of genotoxicity levels by the Comet assay in wild mice can be used as a valuable test in pollution monitoring and environmental conservation. - We have found an increased genotoxic damage in wild mice in a highly polluted area from industry, mining and agriculture in SW Spain, as assessed by the Comet assay.

  3. Cytotoxicity and genotoxicity of intravitreal adalimumab administration in rabbit retinal cells

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    Álcio Coutinho de Paula

    2015-04-01

    Full Text Available Purpose: To assess the cytotoxicity and genotoxicity of intravitreal adalimumab treatment in an animal experimental model using cytological and molecular techniques. Methods: Eighteen rabbits were randomly assigned to three groups: control, adalimumab treatment, and placebo. Cytotoxicity on retinal cells was evaluated using flow cytometry assays to determine the level of apoptosis and necrosis. Genotoxicity was evaluated by comet assays to assess DNA damage, and quantitative real-time polymerase chain reaction (qPCR was used to evaluate expression of apoptosis-inducing caspases (8 and 3. Results: No cytotoxicity or genotoxicity was observed in any of the two treatment groups (adalimumab and placebo following intravitreal administration compared with the control group. Flow cytometry analysis revealed that more than 90% of the cells were viable, and only a low proportion of retinal cells presented apoptotic (~10% or necrotic (<1% activity across all groups. Molecular damage was also low with a maximum of 6.4% DNA degradation observed in the comet assays. In addition, no increase in gene expression of apoptosis-inducing caspases was observed on retinal cells by qPCR in both the adalimumab and placebo groups compared with the control group. Conclusion: The use of adalimumab resulted in no detectable cytotoxicity or genotoxicity on retinal cells for up to 60 days upon administration. These results therefore indicate that adalimumab may be a safe option for intravitreal application to treat ocular inflammatory diseases in which TNF-α is involved.

  4. Assessing the genotoxicity of urban air pollutants using two in situ plant bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Villarini, M.; Fatigoni, C.; Dominici, L.; Maestri, S. [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy); Ederli, L.; Pasqualini, S. [Department of Applied Biology, University of Perugia, I-06121 (Italy); Monarca, S. [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy); Moretti, M., E-mail: massimo.moretti@unipg.i [Department of Medical-Surgical Specialties and Public Health, University of Perugia, I-06126 (Italy)

    2009-12-15

    Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone no. 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air. - Plant bioassays used to explore in situ the correlation between air pollution and genotoxicity.

  5. Cytostatic and genotoxic effect of temephos in human lymphocytes and HepG2 cells.

    Science.gov (United States)

    Benitez-Trinidad, A B; Herrera-Moreno, J F; Vázquez-Estrada, G; Verdín-Betancourt, F A; Sordo, M; Ostrosky-Wegman, P; Bernal-Hernández, Y Y; Medina-Díaz, I M; Barrón-Vivanco, B S; Robledo-Marenco, M L; Salazar, A M; Rojas-García, A E

    2015-06-01

    Temephos is an organophosphorus pesticide that is used in control campaigns against Aedes aegypti mosquitoes, which transmit dengue. In spite of the widespread use of temephos, few studies have examined its genotoxic potential. The aim of this study was to evaluate the cytotoxic, cytostatic and genotoxic effects of temephos in human lymphocytes and hepatoma cells (HepG2). The cytotoxicity was evaluated with simultaneous staining (FDA/EtBr). The cytostatic and genotoxic effects were evaluated using comet assays and the micronucleus technique. We found that temephos was not cytotoxic in either lymphocytes or HepG2 cells. Regarding the cytostatic effect in human lymphocytes, temephos (10 μM) caused a significant decrease in the percentage of binucleated cells and in the nuclear division index as well as an increase in the apoptotic cell frequency, which was not the case for HepG2 cells. The comet assay showed that temephos increased the DNA damage levels in human lymphocytes, but it did not increase the MN frequency. In contrast, in HepG2 cells, temephos increased the tail length, tail moment and MN frequency in HepG2 cells compared to control cells. In conclusion, temephos causes stable DNA damage in HepG2 cells but not in human lymphocytes. These findings suggest the importance of temephos biotransformation in its genotoxic effect.

  6. A pre-validation trial - testing genotoxicity of several chemicals using standard, medium- and high-throughput comet formats.

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    Kristine Bjerve Gutzkow

    2015-06-01

    Results obtained with the three systems (standard, medium- and high-throughput were essentially the same. The 96-minigel format was analysed with the fully automated scoring system IMSTAR and comparable results were achieved with the semi-automated scoring system from Perceptives. The known genotoxic chemicals MNU, B(aP, 4-NQO and cyclophosphamide showed little consistent sign of genotoxicity at concentrations causing limited cytotoxicity. D-mannitol and Triton X-100 were, as expected, non-genotoxic (though Triton X-100, at high concentrations, caused DNA breaks as an apparent secondary effect of cytotoxicity. Etoposide and bleomycin gave significant increase in DNA strand break at borderline cytotoxic concentrations. The limitation of the assay to detect damaged bases by known genotoxins may be overcome by incorporating a DNA repair enzyme, such as formamidopyrimidine-DNA-glycosylase (FPG, to convert damaged bases into breaks as shown by Azqueta A et al., Mutagenesis vol. 28 no. 3 pp. 271–277, 2013 .

  7. Analysis of 75 marketed pharmaceuticals using the GADD45a-GFP 'GreenScreen HC' genotoxicity assay.

    Science.gov (United States)

    Hastwell, Paul W; Webster, Thomas W; Tate, Matthew; Billinton, Nicholas; Lynch, Anthony M; Harvey, James S; Rees, Robert W; Walmsley, Richard M

    2009-09-01

    The GADD45a-GFP (GreenScreen HC) reporter assay detects genotoxic damage in the human lymphoblastoid TK6 cell line and gives positive results for all classes of genotoxin, including mutagens, aneugens and clastogens. In this study, a collection of 75 marketed pharmaceuticals were tested in the assay. Compounds in the collection represent a broad range of chemical structures, pharmacologies and therapeutic indications, including neoplasia and viral infection where positive genotoxicity results are often associated with the pharmacological activity. Based on the results of this study, two main conclusions can be drawn: (i) the GreenScreen HC is more predictive of in vivo genotoxicity (88%) and genotoxic carcinogenicity (93%) data than the any of the other regulatory in vitro genotoxicity assay and (ii) no compounds were uniquely positive in the GADD45a-GFP assay. This analysis therefore provides additional evidence to support the use of the GADD45a-GFP assay as an effective tool either in early genotoxic liability identification or non-clinical safety assessment of candidate pharmaceuticals during development.

  8. Investigating the relationship between embryotoxic and genotoxic effects of benzo[alpha]pyrene, 17 alpha-ethinylestradiol and endosulfan on Crassostrea gigas embryos

    OpenAIRE

    Wessel, Nathalie; Rousseau, Sabrina; Caisey, Xavier; Quiniou, Francoise; Akcha, Farida

    2007-01-01

    Genotoxicity biomarkers are widely measured in ecotoxicology as molecular toxic endpoints of major environmental pollutants. However, the long-term consequences of such damage still have to be elucidated. Some authors have suggested that the accumulation of unrepaired DNA lesions could explain the embryotoxicity of certain chemical pollutants. As embryotoxicity exerts a direct impact on the recruitment rate, genotoxicity could be closely related to disturbances of ecological concern and produ...

  9. Oxidative and genotoxic effects of 900 MHz electromagnetic fields in the earthworm Eisenia fetida.

    Science.gov (United States)

    Tkalec, Mirta; Stambuk, Anamaria; Srut, Maja; Malarić, Krešimir; Klobučar, Göran I V

    2013-04-01

    Accumulating evidence suggests that exposure to radiofrequency electromagnetic field (RF-EMF) can have various biological effects. In this study the oxidative and genotoxic effects were investigated in earthworms Eisenia fetida exposed in vivo to RF-EMF at the mobile phone frequency (900 MHz). Earthworms were exposed to the homogeneous RF-EMF at field levels of 10, 23, 41 and 120 V m(-1) for a period of 2h using a Gigahertz Transversal Electromagnetic (GTEM) cell. At the field level of 23 V m(-1) the effect of longer exposure (4h) and field modulation (80% AM 1 kHz sinusoidal) was investigated as well. All exposure treatments induced significant genotoxic effect in earthworms coelomocytes detected by the Comet assay, demonstrating DNA damaging capacity of 900 MHz electromagnetic radiation. Field modulation additionally increased the genotoxic effect. Moreover, our results indicated the induction of antioxidant stress response in terms of enhanced catalase and glutathione reductase activity as a result of the RF-EMF exposure, and demonstrated the generation of lipid and protein oxidative damage. Antioxidant responses and the potential of RF-EMF to induce damage to lipids, proteins and DNA differed depending on the field level applied, modulation of the field and duration of E. fetida exposure to 900 MHz electromagnetic radiation. Nature of detected DNA lesions and oxidative stress as the mechanism of action for the induction of DNA damage are discussed.

  10. In vivo genotoxicity of nitramines, transformation products of amine-based carbon capture technology

    Directory of Open Access Journals (Sweden)

    Claire Coutris

    2015-05-01

    Full Text Available In times where we need to reduce our CO2 emissions to the atmosphere, it is important to get a clearer picture of the environmental impacts associated with potential mitigation technologies. Chemical absorption with amines is emerging as the most advanced mitigation technology for post-combustion capture of CO2 from fossil fuel power stations. Although the amine solvent used in this technology is recycled during the capture process, degradation products are formed and released into the environment. Among these degradation products, the aliphatic nitramine compounds dimethylnitramine and ethanolnitramine have been identified, whose environmental impact was unknown. In addition to conducting survival, growth and reproduction tests in a range of marine species, we looked into the in vivo genotoxic potential of these two compounds to experimentally exposed fish (Coutris et al. 2015. DNA damage was analyzed in blood samples collected from the caudal vein of juvenile turbot Scophthalmus maximus after 28 day exposure to nitramines, using the 12 mini-gels version of the comet assay, with and without digestion with formamidopyrimidine DNA glycosylase. Although whole organism bioassays indicated that nitramine toxicity through necrosis was low, the genotoxicity assessment revealed contrasting results, with ethanolnitramine found to be more genotoxic than dimethylnitramine by three orders of magnitude. At the lowest ethanolnitramine concentration (1 mg/L, 84 % DNA damage was observed, whereas 100 mg/L dimethylnitramine was required to cause 37 % DNA damage. The mechanisms of genotoxicity were also shown to differ between the two compounds, with oxidation of the DNA bases responsible for over 90 % of the genotoxicity of dimethylnitramine, whereas DNA strand breaks and alkali-labile sites were responsible for over 90 % of the genotoxicity of ethanolnitramine. Fish exposed to > 3 mg/L ethanolnitramine had virtually no DNA left in their red blood cells. The

  11. Comparative assessment of genotoxicity of mineral water packed in polyethylene terephthalate (PET) and glass bottles.

    Science.gov (United States)

    Ceretti, Elisabetta; Zani, Claudia; Zerbini, Ilaria; Guzzella, Licia; Scaglia, Mauro; Berna, Vanda; Donato, Francesco; Monarca, Silvano; Feretti, Donatella

    2010-03-01

    The potential migration of genotoxic compounds into mineral water stored in polyethylene terephthalate (PET) bottles was evaluated by an integrated chemical/biological approach using short-term toxicity/genotoxicity tests and chemical analysis. Six commercial brands of still and carbonated mineral water bottled in PET and in glass were stored at 40 degrees C for 10 days in a stove according to the standard EEC total migration test (82/711/EEC), or at room temperature in the dark. After treatment, the samples were analysed using gas-chromatography/mass spectrometry (GC/MS) to detect volatile and non-volatile compounds, the Microtox test to evaluate potential toxicity of the samples, and three mutagenicity tests -Tradescantia and Allium cepa micronucleus tests and the Comet assay on human leukocytes - to detect their genotoxic activity. GC/MS analysis did not detect phthalates or acetaldehyde in the water samples. The Microtox test found no toxic effects. Mutagenicity tests detected genotoxic properties of some samples in both PET and glass bottles. Statistical analyses showed a positive association between mineral content and mutagenicity (micronuclei in A. cepa and DNA damage in human leukocytes). No clear effect of treatment and PET bottle was found. These results suggest the absence of toxic compounds migrating from PET regardless of time and conditions of storage. In conclusion, bottle material and stove treatment were not associated with the genotoxic properties of the water; the genotoxic effects detected in bottled water may be related to the characteristics of the water (minerals and CO(2) content).

  12. DNA damage and autophagy

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Rocha, Humberto; Garcia-Garcia, Aracely [Redox Biology Center and School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583 (United States); Panayiotidis, Mihalis I. [School of Community Health Sciences, University of Nevada, Reno, NV 89557 (United States); Franco, Rodrigo, E-mail: rfrancocruz2@unl.edu [Redox Biology Center and School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583 (United States)

    2011-06-03

    Both exogenous and endogenous agents are a threat to DNA integrity. Exogenous environmental agents such as ultraviolet (UV) and ionizing radiation, genotoxic chemicals and endogenous byproducts of metabolism including reactive oxygen species can cause alterations in DNA structure (DNA damage). Unrepaired DNA damage has been linked to a variety of human disorders including cancer and neurodegenerative disease. Thus, efficient mechanisms to detect DNA lesions, signal their presence and promote their repair have been evolved in cells. If DNA is effectively repaired, DNA damage response is inactivated and normal cell functioning resumes. In contrast, when DNA lesions cannot be removed, chronic DNA damage triggers specific cell responses such as cell death and senescence. Recently, DNA damage has been shown to induce autophagy, a cellular catabolic process that maintains a balance between synthesis, degradation, and recycling of cellular components. But the exact mechanisms by which DNA damage triggers autophagy are unclear. More importantly, the role of autophagy in the DNA damage response and cellular fate is unknown. In this review we analyze evidence that supports a role for autophagy as an integral part of the DNA damage response.

  13. Comparative Genotoxicity of Cadmium and Lead in Earthworm Coelomocytes

    Directory of Open Access Journals (Sweden)

    Ptumporn Muangphra

    2011-01-01

    Full Text Available To determine genotoxicity to coelomocytes, Pheretima peguana earthworms were exposed in filter paper studies to cadmium (Cd and lead (Pb for 48 h, at concentrations less than the LC10—Cd: 0.09, 0.19, 0.38, 0.75, and 1.50 μg cm−2; Pb: 1.65, 3.29, 6.58, 13.16, and 26.32 μg cm−2. For Cd at 0.75 μg cm−2, in the micronucleus test (detects chromosomal aberrations, significant increases (<.05 in micronuclei and binucleate cells were observed, and in the comet assay (detects DNA single-strand breaks, tail DNA% was significantly increased. Lead was less toxic with minimal effects on DNA, but the binucleates were significantly increased by Pb at 3.29 μg cm−2. This study shows that Cd is more acutely toxic and sublethally genotoxic than Pb to P. peguana. Cadmium caused chromosomal aberrations and DNA single-strand breaks at 45% of the LC10 concentration. Lead, in contrast, did not induce DNA damage but caused cytokinesis defects.

  14. Genotoxicity biomarkers for monitoring occupational exposure to antineoplastic drugs

    Directory of Open Access Journals (Sweden)

    Hilda M. Rodríguez-Montero

    2016-06-01

    Full Text Available Context: The Institute of Oncology and Radiobiology (INOR is the leading institution for the diagnosis, treatment and follow-up of cancer in Cuba. The main methods used in cancer treatment are surgery, radiotherapy and chemotherapy. The last one involves the handling of hazardous substances, such as cytostatics, which implies a health risk to persons occupationally exposed to it. There are two sites where a considerable among of cytostatic is handled (Ambulatory Chemotherapy Room (ACR and the Central Unit of Cytostatic Mixture Preparation (CUCM. Genotoxicity biomarkers of exposure and effects have been widely used to detect occupational environment hazards. Aims: To evaluate genotoxicity biomarkers indicative of exposure and effects to cytostatics. Methods: In this study were tested samples taken from the surfaces of biological safety cabinets located in the Central Unit of Cytostatic Mixture using SOS – Chromotest. We also evaluated samples of oral mucosa exfoliated cells from exposed and control subjects, by micronucleus test. Results: All subjects were exposed and subjects who administered the mixes in the institution had an increased of DNA damage in comparison with the pharmaceutical staff that prepared it and wear the primary protection barriers properly. Conclusions: These results underline the efficiency of genotoxicological biomarkers in detecting the exposure levels and the deleterious effect of cytostatics on occupationally exposed personal.

  15. Genotoxic effects of bismuth (III oxide nanoparticles by comet assay

    Directory of Open Access Journals (Sweden)

    Reecep Liman

    2015-06-01

    Full Text Available Bismuth oxide is one of the important transition metal oxides and it has been intensively studied due to their peculiar characteristics (semiconductor band gap, high refractive index, high dielectric permittivity, high oxygen conductivity, resistivity, photoconductivity and photoluminescence etc.. Therefore, it is used such as microelectronics, sensor technology, optical coatings, transparent ceramic glass manufacturing, nanoenergetic gas generator, biosensor for DNA hybridization, potential immobilizing platforms for glucose oxidase and polyphenol oxidase, fuel cells, a additive in paints, an astringent in a variety of medical creams and topical ointments, and for the determination of heavy metal ions in drinking water, mineral water and urine. In addition this, Bismuth (III oxide nanoparticles (BONPs are favorable for the biomolecules adsorption than regular sized particles because of their greater advantages and novel characteristics (much higher specific surface, greater surface free energy, and good electrochemical stability etc.. Genotoxic effects of BONPs were investigated on the root cells of Allium cepa by Comet assay. A. cepa roots were treated with the aqueous dispersions of BONPs at 5 different concentrations (12.5, 25, 50, 75, and 100 ppm for 4 h. A significant increase in DNA damage was also observed at all concentrations of BONPs except 12.5 ppm by Comet assay. The results were also analyzed statistically by using SPSS for Windows; Duncan’s multiple range test was performed. These result indicate that BONPs exhibit genotoxic activity in A. cepa root meristematic cells.

  16. Argentine folk medicine: genotoxic effects of Chenopodiaceae family.

    Science.gov (United States)

    Gadano, A B; Gurni, A A; Carballo, M A

    2006-01-16

    Chenopodium ambrosioides L. and Chenopodium multifidum L. (Chenopodiaceae), common name: Paico, are medicinal plants. They are aromatic shrubs growing in South America. For centuries, they have been used due to its medicinal properties. However, there are few reports in literature about the genotoxic effects of these plants. There for, the aim of these work is the evaluation of genetic damage induced by decoction and infusion of this plants which were assayed in different concentrations (1, 10, 100, 1,000 microL extract/mL culture), by addition of the extract to human lymphocyte cell cultures, negative controls were included. The endpoints evaluated were chromosomal aberrations (CA), sister chromatid exchanges (SCE), cell proliferation kinetics (CPK) and mitotic index (MI). The repeated measure analysis of variance was used for statistic evaluation of the results. The results showed: (a) statistical increase in the percentage of cells with CA and in the frequency of SCE when cultures were exposed to both aromatic plants, (b) a decrease in MI of both Paicos assayed, although no modification in the CPK values was observed, (c) no effect was noticed in the analysis of Chenopodium album L., which was used as negative control of the essential oil. These results suggest a cyto and genotoxic effect of Chenopodium ambrosioides and Chenopodium multifidum aqueous extracts related to the essential oil of the plant (as Chenopodium album did not perform).

  17. The comet assay in testing the potential genotoxicity of nanomaterials

    Directory of Open Access Journals (Sweden)

    Amaya Azqueta

    2015-06-01

    validation. The comet assay has not been yet proposed as an appropriate test to check the genotoxic potential of NMs, though at a research level it is the most used in vitro assay and the second most used in vivo assay. Moreover, the combination of the comet assay with enzymes that convert altered bases to breaks allows the identification of DNA damage induced by secondary mechanisms (e.g. oxidative stress induced by inflammation, which is very relevant in the case of NMs. Possible problems with the use of the comet assay have been suggested: NMs have been detected in close association with comets, and might interact with the DNA; or NMs might inhibit the action of enzymes. However, control experiments have not confirmed that these interactions are significant.

  18. Electrochemical Genotoxicity Assay Based on a SOS/umu Test Using Hydrodynamic Voltammetry in a Droplet

    OpenAIRE

    Kazuharu Sugawara; Masami Fukushima; Shigeru Taguchi; Noriko Hata; Kazuto Sazawa; Yasuaki Nanayama; Hideki Kuramitz

    2012-01-01

    The SOS/umu genotoxicity assay evaluates the primary DNA damage caused by chemicals from the β-galactosidase activity of S. typhimurium. One of the weaknesses of the common umu test system based on spectrophotometric detection is that it is unable to measure samples containing a high concentration of colored dissolved organic matters, sediment, and suspended solids. However, umu tests with electrochemical detection techniques prove to be a better strategy because it causes less inter...

  19. Assessing the genotoxic potentials of roxarsone in V79 cells using the alkaline Comet assay and micronucleus test.

    Science.gov (United States)

    Zhang, Yumei; Ying, Jun; Chen, Jun; Hu, Chenyun

    2012-01-24

    Until recently, knowledge about the genotoxicity of roxarsone in vitro or in vivo was limited. This study assessed the genotoxicity of roxarsone in an in vitro system. Roxarsone was tested for potential genotoxicity on V79 cells by a Comet assay and a micronucleus (MN) test, exposing the cells to roxarsone (1-500 μM) and to sodium arsenite (NaAsO₂, 20 μM) solutions for 3-48 h. Roxarsone was found to be cytotoxic when assessed with a commercial cell counting kit (CCK-8) used to evaluate cell viability, and moderately genotoxic in the Comet assay and micronucleus test used to assess DNA damage. The Comet metrics (percentages TDNA, TL, TM) increased significantly in a time- and concentration-dependent manner in roxarsone-treated samples compared with PBS controls (Proxarsone-treated samples. The MN frequency of V79 cells treated with roxarsone was higher than that in the negative control but lower than the frequency in cells treated with 20 μM NaAsO₂. A dose- and time-dependent response in MN induction was observed at 10, 50, 100 and 500 μM doses of roxarsone after 12-48 h exposure time. The DNA damage in V79 cells treated with 500 μM roxarsone was similar to cells exposed to 20 μM NaAsO₂. The uptake of cells was correlated with the DNA damage caused by roxarsone. This investigation depicts the genotoxic potentials of roxarsone to V79 cells, which could lead to further advanced studies on the genotoxicity of roxarsone.

  20. Genotoxic Effect in Autoimmune Diseases Evaluated by the Micronucleus Test Assay: Our Experience and Literature Review

    Science.gov (United States)

    Torres-Bugarín, Olivia; Macriz Romero, Nicole; Ramos Ibarra, María Luisa; Flores-García, Aurelio; Valdez Aburto, Penélope; Zavala-Cerna, María Guadalupe

    2015-01-01

    Autoimmune diseases (AD) are classified into organ-specific, systemic, and mixed; all forms of AD share a high risk for cancer development. In AD a destructive immune response induced by autoreactive lymphocytes is started and continues with the production of autoantibodies against different targets; furthermore apoptosis failure and loss of balance in oxidative stress as a consequence of local or systemic inflammation are common features seen in AD as well. Micronucleus (MN) assay can be performed in order to evaluate loss of genetic material in a clear, accurate, fast, simple, and minimally invasive test. The MN formation in the cytoplasm of cells that have undergone proliferation is a consequence of DNA fragmentation during mitosis and the appearance of small additional nuclei during interphase. The MN test, widely accepted for in vitro and in vivo genotoxicity research, provides a sensitive marker of genomic damage associated to diverse conditions. In here, we present a review of our work and other published papers concerning genotoxic effect in AD, identified by means of the MN assay, with the aim of proposing this tool as a possible early biomarker for genotoxic damage, which is a consequence of disease progression. Additionally this biomarker could be used for follow-up, to asses genome damage associated to therapies. PMID:26339592

  1. Genotoxic Effect in Autoimmune Diseases Evaluated by the Micronucleus Test Assay: Our Experience and Literature Review

    Directory of Open Access Journals (Sweden)

    Olivia Torres-Bugarín

    2015-01-01

    Full Text Available Autoimmune diseases (AD are classified into organ-specific, systemic, and mixed; all forms of AD share a high risk for cancer development. In AD a destructive immune response induced by autoreactive lymphocytes is started and continues with the production of autoantibodies against different targets; furthermore apoptosis failure and loss of balance in oxidative stress as a consequence of local or systemic inflammation are common features seen in AD as well. Micronucleus (MN assay can be performed in order to evaluate loss of genetic material in a clear, accurate, fast, simple, and minimally invasive test. The MN formation in the cytoplasm of cells that have undergone proliferation is a consequence of DNA fragmentation during mitosis and the appearance of small additional nuclei during interphase. The MN test, widely accepted for in vitro and in vivo genotoxicity research, provides a sensitive marker of genomic damage associated to diverse conditions. In here, we present a review of our work and other published papers concerning genotoxic effect in AD, identified by means of the MN assay, with the aim of proposing this tool as a possible early biomarker for genotoxic damage, which is a consequence of disease progression. Additionally this biomarker could be used for follow-up, to asses genome damage associated to therapies.

  2. Genotoxic Effect in Autoimmune Diseases Evaluated by the Micronucleus Test Assay: Our Experience and Literature Review.

    Science.gov (United States)

    Torres-Bugarín, Olivia; Macriz Romero, Nicole; Ramos Ibarra, María Luisa; Flores-García, Aurelio; Valdez Aburto, Penélope; Zavala-Cerna, María Guadalupe

    2015-01-01

    Autoimmune diseases (AD) are classified into organ-specific, systemic, and mixed; all forms of AD share a high risk for cancer development. In AD a destructive immune response induced by autoreactive lymphocytes is started and continues with the production of autoantibodies against different targets; furthermore apoptosis failure and loss of balance in oxidative stress as a consequence of local or systemic inflammation are common features seen in AD as well. Micronucleus (MN) assay can be performed in order to evaluate loss of genetic material in a clear, accurate, fast, simple, and minimally invasive test. The MN formation in the cytoplasm of cells that have undergone proliferation is a consequence of DNA fragmentation during mitosis and the appearance of small additional nuclei during interphase. The MN test, widely accepted for in vitro and in vivo genotoxicity research, provides a sensitive marker of genomic damage associated to diverse conditions. In here, we present a review of our work and other published papers concerning genotoxic effect in AD, identified by means of the MN assay, with the aim of proposing this tool as a possible early biomarker for genotoxic damage, which is a consequence of disease progression. Additionally this biomarker could be used for follow-up, to asses genome damage associated to therapies.

  3. Genotoxicity studies on green tea catechin.

    Science.gov (United States)

    Ogura, R; Ikeda, N; Yuki, K; Morita, O; Saigo, K; Blackstock, C; Nishiyama, N; Kasamatsu, T

    2008-06-01

    The beneficial effects of tea catechins are well documented. We evaluated the genotoxic potential of a green tea catechin preparation using established genotoxicity assays, including a bacterial reverse mutation assay (Ames test), a chromosomal aberration assay in cultured Chinese hamster lung cells (CHL/IU), a mouse lymphoma L5178Y/tk assay, and a bone marrow micronucleus (MN) assay in ICR CD mice and SD rats. No significant increases in the number of revertant colonies were observed in the Ames test, but positive responses were observed in two in vitro assays: the chromosomal aberration assay and mouse lymphoma L5178/tk assay. However, the in vivo study demonstrated no significant increase in micronucleated polychromatic erythrocytes (MNPCE) in the bone marrow of both ICR CD mice and SD rats administered a high dose of the green tea catechin preparation up to 2000mg/kg. Combined with favorable epidemiological information suggesting a chemopreventive effect of tea catechins on carcinogenesis, we conclude that green tea catechin presents no significant genotoxic concern under the anticipated conditions of use. These results are consistent with other genotoxicity studies of tea catechins, which show minimal, if any, genotoxic potential.

  4. Genotoxic potential of Cotinus coggygria Scop. (Anacardiaceae stem extract in vivo

    Directory of Open Access Journals (Sweden)

    Sanja Matic

    2011-01-01

    Full Text Available The intention was to evaluate the possible in vivo genotoxic potential in different cell-types, of a methanol extract obtained from the plant stem of Cotinus coggygria Scop., using the sex-linked recessive lethal (or SLRL test and alkaline comet assay. The SLRL test, revealed the genotoxic effect of this extract in postmeiotic and premeiotic germ-cell lines. The comet assay was carried out on rat liver and bone marrow at 24 and 72 h after intraperitoneal administration. For genotoxic evaluation, three concentrations of the extract were tested, viz., 500, 1000 and 2000 mg/kg body weight (bw, based on the solubility limit of the extract in saline. Comet tail moment and total scores in the group treated with 500 mg/kg bw, 24 and 72 h after treatment, were not significantly different from the control group, whereas in the groups of animals, under the same conditions, but with 1000 and 2000 mg/kg bw of the extract, scores were statistically so. A slight decrease in the comet score and tail moment observed in all the doses in the 72 h treatment, gave to understand that DNA damage induced by Cotinus coggygria extract decreased with time. The results of both tests revealed the genotoxic effect of Cotinus coggygria under our experimental conditions.

  5. Immunocytotoxicity, cytogenotoxicity and genotoxicity of cadmium-based quantum dots in the marine mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Rocha, Thiago Lopes; Gomes, Tânia; Cardoso, Cátia; Letendre, Julie; Pinheiro, José Paulo; Sousa, Vânia Serrão; Teixeira, Margarida Ribau; Bebianno, Maria João

    2014-10-01

    There is an increased use of Quantum Dot (QDs) in biological and biomedical applications, but little is known about their marine ecotoxicology. So, the aim of this study was to investigate the possible immunocytotoxic, cytogenotoxic and genotoxic effects of cadmium telluride QDs (CdTe QDs) on the marine mussel Mytilus galloprovincialis. Mussels were exposed to 10 μg L(-1) of CdTe QDs or to soluble Cd [Cd(NO3)2] for 14 days and Cd accumulation, immunocytotoxicity [hemocyte density, cell viability, lysosomal membrane stability (LMS), differential cell counts (DCC)], cytogenotoxicity (micronucleus test and nuclear abnormalities assay) and genotoxicity (comet assay) were analyzed. Results show that in vivo exposure to QDs, Cd is accumulated in mussel soft tissues and hemolymph and induce immunotoxic effects mediated by a decrease in LMS, changes in DCC, as well as genotoxicity (DNA damage). However, QDs do not induce significant changes in hemocytes density, cell viability and cytogenetic parameters in opposition to Cd(2+). Soluble Cd is the most cytotoxic and cytogenotoxic form on Mytilus hemocytes due to a higher accumulation of Cd in tissues. Results indicate that immunotoxicity and genotoxicity of CdTe QDs and Cd(2+) are mediated by different modes of action and show that Mytilus hemocytes are important targets for in vivo QDs toxicity.

  6. Gamma radiation at a human relevant low dose rate is genotoxic in mice

    Science.gov (United States)

    Graupner, Anne; Eide, Dag M.; Instanes, Christine; Andersen, Jill M.; Brede, Dag A.; Dertinger, Stephen D.; Lind, Ole C.; Brandt-Kjelsen, Anicke; Bjerke, Hans; Salbu, Brit; Oughton, Deborah; Brunborg, Gunnar; Olsen, Ann K.

    2016-09-01

    Even today, 70 years after Hiroshima and accidents like in Chernobyl and Fukushima, we still have limited knowledge about the health effects of low dose rate (LDR) radiation. Despite their human relevance after occupational and accidental exposure, only few animal studies on the genotoxic effects of chronic LDR radiation have been performed. Selenium (Se) is involved in oxidative stress defence, protecting DNA and other biomolecules from reactive oxygen species (ROS). It is hypothesised that Se deficiency, as it occurs in several parts of the world, may aggravate harmful effects of ROS-inducing stressors such as ionising radiation. We performed a study in the newly established LDR-facility Figaro on the combined effects of Se deprivation and LDR γ exposure in DNA repair knockout mice (Ogg1‑/‑) and control animals (Ogg1+/‑). Genotoxic effects were seen after continuous radiation (1.4 mGy/h) for 45 days. Chromosomal damage (micronucleus), phenotypic mutations (Pig-a gene mutation of RBCCD24‑) and DNA lesions (single strand breaks/alkali labile sites) were significantly increased in blood cells of irradiated animals, covering three types of genotoxic activity. This study demonstrates that chronic LDR γ radiation is genotoxic in an exposure scenario realistic for humans, supporting the hypothesis that even LDR γ radiation may induce cancer.

  7. Aporrectodea caliginosa, a suitable earthworm species for field based genotoxicity assessment?

    Energy Technology Data Exchange (ETDEWEB)

    Klobucar, Goeran I.V., E-mail: gklobuca@zg.biol.pmf.hr [Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb (Croatia); Stambuk, Anamaria; Srut, Maja [Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb (Croatia); Husnjak, Ivana [Ministry of Environmental Protection, Physical Planning and Construction, Ulica Republike Austrije 14, Zagreb (Croatia); Merkas, Martina [Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 12, 10000 Zagreb (Croatia); Traven, Luka [Department of Environmental Medicine, Medical Faculty, University of Rijeka, Brace Branchetta 20a, 51000 Rijeka (Croatia); Teaching Institute of Public Health of the Primorsko-goranska County, Kresimirova 52a, 51000 Rijeka (Croatia); Cvetkovic, Zelimira [Department of Ecology, Institute of Public Health, Mirogojska c. 16, 10000 Zagreb (Croatia)

    2011-04-15

    There is a growing interest for the application of biomakers to field-collected earthworms. Therefore we have evaluated the usability of native populations of endogeic, widely distributed earthworm Aporrectodea caliginosa in the assessment of soil genotoxicity using the Comet assay. Validation of the Comet assay on earthworm coelomocytes has been established using commercially available Eisenia fetida exposed to copper, cadmium, and pentachlorophenol, along with A. caliginosa exposed to copper in a filter paper contact test. Neutral red retention time (NRRT) assay was conducted on copper exposed and field-collected earthworms. Significant DNA and lysosomal damage was measured using Comet and NRRT assays in native populations of A. caliginosa sampled from the polluted soils in the urban area in comparison to the earthworms from the reference site. The results of this study confirm the employment of A. caliginosa as a suitable species for the in situ soil toxicity and genotoxicity field surveys. - Research highlights: > Native A. caliginosa has shown significant biological effect measured by the Comet and NRRT assays. > The Comet assay on A. caliginosa and E. fetida has shown to be of similar sensitivity as the NRRT assay. > A. caliginosa is a suitable species for the in situ soil toxicity and genotoxicity field surveys. - Native populations of endogeic earthworm Aporrectodea caliginosa can be successfully applied in the genotoxicity field surveys using Comet assay.

  8. Evaluation of the Bronchorelaxant, Genotoxic, and Antigenotoxic Effects of Cassia alata L.

    Directory of Open Access Journals (Sweden)

    M. Ouédraogo

    2013-01-01

    Full Text Available Aqueous-ethanolic extract of Cassia alata (AECal and its derived fractions obtained through liquid-liquid fractionation were evaluated for their bronchorelaxant, genotoxic, and antigenotoxic effects. Contractile activity of rats’ tracheas in the presence of tested materials, as well as its modifications with different inhibitors and blockers, was isometrically recorded. The antigenotoxic potential of AECal was evaluated on cyclophosphamide- (CP- induced genotoxicity in the rat. Animals were pretreated with the extract, then liver comet assay was performed. AECal and its chloroformic fractions (CF-AECal relaxed the contraction induced by Ach, but both were significantly less potent in inhibiting contraction induced by KCl (30 mM; 80 mM. Propranolol, indomethacin, L-NAME, methylene blue, and glibenclamide did not modify the relaxant effect of CF-AECal. TEA altered the response of trachea to CF-AECal. CF-AECal caused a rightward shift without affecting the Emax in cumulative concentration-response curves of Ach only at low concentrations. In animals pretreated with the extract, the percentage of CP-induced DNA damage decreased. Our results suggest that (1 muscarinic receptors contribute at least in part to the relaxant effects of CF-AECal; (2 CF-AECal interferes with membrane polarization; and (3 AECal is not genotoxic in vivo and contains chemopreventive phytoconstituents offering protection against CP-induced genotoxicity.

  9. Delineating the DNA damage response using systems biology approaches

    NARCIS (Netherlands)

    Stechow, Louise von

    2013-01-01

    Cellular responses to DNA damage are highly variable and strongly depend on the cellular and organismic context. Studying the DNA damage response is crucial for a better understanding of cancer formation and ageing as well as genotoxic stress-induced cancer therapy. To do justice to the multifaceted

  10. The potential for new methods to assess human reproductive genotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Mendelsohn, M.L.

    1987-09-01

    The immediate prospects are not good for practical methods for measuring the human heritable mutation rate. The methods discussed here range from speculative to impractical, and at best are sensitive enough only for large numbers of subjects. Given the rapid development of DNA methods and the current status of two-dimensional gel electrophoresis, there is some hope that the intermediate prospects may be better. In contrast, the prospects for useful cellular-based male germinal methods seem more promising and immediate. Effective specific locus methods for sperm are already conceivable and may be practical in a few years. Obviously such methods will not predict heritable effects definitively, but they will provide direct information on reproductive genotoxicity and should contribute significantly to many current medical and environmental situations where genetic damage is suspected. 22 refs.

  11. Neurobehavioral and genotoxic parameters of antipsychotic agent aripiprazole in mice

    Institute of Scientific and Technical Information of China (English)

    Jaqueline Nascimento PICADA; Viviane Minuzzo PONTES; Patrícia PEREIRA; Bruna de Jesus Neto DOS SANTOS; Franciele CELSO; Jéssica Dias MONTEIRO; Kelly Morais DA ROSA; Leandro Rosa CAMACHO; Luciana Rodrigues VIEIRA; Taís Madelon FREITAS; Tatiana Grasiela DASILVA

    2011-01-01

    Aim:Aripiprazole is an antipsychotic agent to treat schizophrenia,which acts through dopamine D2 partial agonism,serotonin 5-HT1A partial agonism and 5-HT2A antagonism.This study was designed to evaluate the neurobehavioral effects and genotoxic/mutagenic activities of the agent,as well as its effects on lipoperoxidation.Methods:Open field and inhibitory avoidance tasks were used.Thirty min before performing the behavioral tasks,adult male CF-1 mice were administered aripiprazole (1,3 or 10 mg/kg,ip) once for the acute treatment,or the same doses for 5 d for the subchronic treatment.Genotoxic effects were assessed using comet assay in the blood and brain tissues.Mutagenic effects were evaluated using bone marrow micronucleus test.Lipoperoxidation was assessed with thiobarbituric acid reactive substances (TBARS).Results:Acute and subchronic treatments significantly decreased the number of crossing and rearing in the open field task.Acute treatment significantly increased the step-down latency for both the short- and long-term memory in the inhibitory avoidance task.Subchronic treatments with aripiprazole (3 and 10 mg/kg) caused significant DNA strain-break damage in peripheral blood but not in the brain.Mutagenic effect was not detected in the acute and subchronic treatments.Nor TBARS levels in the liver were affected.Conclusion:Aripiprazole improved memory,but could impair motor activities in mice.The drug increased DNA damage in blood,but did not show mutagenic effects,suggesting that it might affect long-term genomic stability.

  12. Cobalt and antimony: genotoxicity and carcinogenicity.

    Science.gov (United States)

    De Boeck, Marlies; Kirsch-Volders, Micheline; Lison, Dominique

    2003-12-10

    The purpose of this review is to summarise the data concerning genotoxicity and carcinogenicity of Co and Sb. Both metals have multiple industrial and/or therapeutical applications, depending on the considered species. Cobalt is used for the production of alloys and hard metal (cemented carbide), diamond polishing, drying agents, pigments and catalysts. Occupational exposure to cobalt may result in adverse health effects in different organs or tissues. Antimony trioxide is primarily used as a flame retardant in rubber, plastics, pigments, adhesives, textiles, and paper. Antimony potassium tartrate has been used worldwide as an anti-shistosomal drug. Pentavalent antimony compounds have been used for the treatment of leishmaniasis. Co(II) ions are genotoxic in vitro and in vivo, and carcinogenic in rodents. Co metal is genotoxic in vitro. Hard metal dust, of which occupational exposure is linked to an increased lung cancer risk, is proven to be genotoxic in vitro and in vivo. Possibly, production of active oxygen species and/or DNA repair inhibition are mechanisms involved. Given the recently provided proof for in vitro and in vivo genotoxic potential of hard metal dust, the mechanistic evidence of elevated production of active oxygen species and the epidemiological data on increased cancer risk, it may be advisable to consider the possibility of a new evaluation by IARC. Both trivalent and pentavalent antimony compounds are generally negative in non-mammalian genotoxicity tests, while mammalian test systems usually give positive results for Sb(III) and negative results for Sb(V) compounds. Assessment of the in vivo potential of Sb2O3 to induce chromosome aberrations (CA) gave conflicting results. Animal carcinogenicity data were concluded sufficient for Sb2O3 by IARC. Human carcinogenicity data is difficult to evaluate given the frequent co-exposure to arsenic. Possible mechanisms of action, including potential to produce active oxygen species and to interfere with

  13. Genotoxic evaluation of polymeric nanoparticles

    Directory of Open Access Journals (Sweden)

    Tamara Iglesias Alonso

    2015-06-01

    Full Text Available An important strategy for optimizing the therapeutic efficacy of many conventional drugs is the development of polymeric nanoparticles (NPs, as it may expand their activities, reduce their toxicity, increase their bioactivity and improve biodistribution. The main objective of this study was to evaluate the genotoxicity of 8 different poly (anhydride NPs designed for the oral administration of therapeutic compounds by using the comet assay in combination with the enzyme formamidopypiridine DNA-glycosylase (FPG. Furthermore, the mitogen capacity of the NPs was evaluated by the proliferation assay. All NPs were tested at four concentrations (0, 0.5, 1 and 2 mg/mL in Caco-2 cells after 3 hours of treatment while selected NPs were also tested after 24 h. The comet assay was performed immediately after the treatment and cell proliferation was assessed by counting the treated cells after their incubation at 37 °C for 48h. Cells treated with 1 µM of the photosensitizer Ro 19-8022 plus 5 min of light, as well as cells treated with 100 µM H2O2 were included as positive controls in all the experiments. All NPs studied did not result in any increase in the frequency of strand breaks or alkali-labile sites in Caco-2 cells but they induced a slight concentration-dependent increase in net FPG sensitive sites (oxidized and/or alkylated bases. Furthermore, treated cells did not show changes in levels of proliferation in comparison with the negative control.

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

    Science.gov (United States)

    Hobbs, Cheryl A; Recio, Leslie; Streicker, Michael; Boyle, Molly H; Tanaka, Jin; Shiga, Atsushi; Witt, Kristine L

    2015-07-01

    As a part of an international validation of the in vivo rat alkaline comet assay (comet assay) initiated by the Japanese Center for the Validation of Alternative Methods (JaCVAM) we examined six chemicals for potential to induce DNA damage: 2-acetylaminofluorene (2-AAF), N-nitrosodimethylamine (DMN), o-anisidine, 1,2-dimethylhydrazine dihydrochloride (1,2-DMH), sodium chloride, and sodium arsenite. DNA damage was evaluated in the liver and stomach of 7- to 9-week-old male Sprague Dawley rats. Of the five genotoxic carcinogens tested in our laboratory, DMN and 1,2-DMH were positive in the liver and negative in the stomach, 2-AAF and o-anisidine produced an equivocal result in liver and negative results in stomach, and sodium arsenite was negative in both liver and stomach. 1,2-DMH and DMN induced dose-related increases in hedgehogs in the same tissue (liver) that exhibited increased DNA migration. However, no cytotoxicity was indicated by the neutral diffusion assay (assessment of highly fragmented DNA) or histopathology in response to treatment with any of the tested chemicals. Therefore, the increased DNA damage resulting from exposure to DMN and 1,2-DMH was considered to represent a genotoxic response. Sodium chloride, a non-genotoxic non-carcinogen, was negative in both tissues as would be predicted. Although only two (1,2-DMH and DMN) out of five genotoxic carcinogens produced clearly positive results in the comet assay, the results obtained for o-anisidine and sodium arsenite in liver and stomach cells are consistent with the known mode of genotoxicity and tissue specificity exhibited by these carcinogens. In contrast, given the known genotoxic mode-of-action and target organ carcinogenicity of 2-AAF, it is unclear why this chemical failed to convincingly increase DNA migration in the liver. Thus, the results of the comet assay validation studies conducted in our laboratory were considered appropriate for five out of the six test chemicals.

  15. Genotoxicity assessment of reactive and disperse textile dyes using human dermal equivalent (3D cell culture system).

    Science.gov (United States)

    Leme, Daniela Morais; Primo, Fernando Lucas; Gobo, Graciely Gomides; da Costa, Cleber Rafael Vieira; Tedesco, Antonio Claudio; de Oliveira, Danielle Palma

    2015-01-01

    Thousands of dyes are marketed daily for different purposes, including textile dyeing. However, there are several studies reporting attributing to dyes deleterious human effects such as DNA damage. Humans may be exposed to toxic dyes through either ingestion of contaminated waters or dermal contact with colored garments. With respect to dermal exposure, human skin equivalents are promising tools to assess in vitro genotoxicity of dermally applied chemicals using a three-dimensional (3D) model to mimic tissue behavior. This study investigated the sensitivity of an in-house human dermal equivalent (DE) for detecting genotoxicity of textile dyes. Two azo (reactive green 19 [RG19] and disperse red 1[DR1]) dyes and one anthraquinone (reactive blue 2 [RB2]) dye were analyzed. RG19 was genotoxic for DE in a dose-responsive manner, whereas RB2 and DR1 were nongenotoxic under the conditions tested. These findings are not in agreement with previous genotoxicological assessment of these dyes carried out using two-dimensional (2D) cell cultures, which showed that DR1 was genotoxic in human hepatoma cells (HepG2) and RG19 was nongenotoxic for normal human dermal fibroblasts (NHDF). These discrepant results probably may be due to differences between metabolic activities of each cell type (organ-specific genotoxicity, HepG2 and fibroblasts) and the test setup systems used in each study (fibroblasts cultured at 2D and three-dimensional [3D] culture systems). Genotoxicological assessment of textile dyes in context of organ-specific genotoxicity and using in vitro models that more closely resemble in vivo tissue architecture and physiology may provide more reliable estimates of genotoxic potential of these chemicals.

  16. p53 Promoter-based Reporter Gene in vitro Assays for Quick Assessment of Agents with Genotoxic Potential

    Institute of Scientific and Technical Information of China (English)

    Huaixing LI; Ke SHI; Ruiwen CHEN; Yan HE; Dan WU; Shuhan SUN

    2007-01-01

    The p53 promoter-based green fluorescent protein (GFP) and luciferase reporter gene assays have been established for detecting DNA damage induced by genotoxic agents.To evaluate the system,NIH3T3 cells transfected with either pHP53-GFP or pMP53-GFP construct were treated with mitomycin or 5-fluorouracil.Expression of the GFP reporter gene was significantly and specifically induced in the cells exposed to mitomycin or 5-fluorouracil.Then we treated NIH3T3 cells harboring pHP53-Luc or pMP53-Luc vector with mitomycin,5-fluorouracil or cisplatin at various concentrations.Similarly,exposure of the cells to these agents with genotoxic potentials resulted in a dose-dependent induction in luciferase reporter gene expression.Thus,these in vitro reporter gene assays could provide an ideal system for quick assessment or screening of agents with genotoxic potential.

  17. Genotoxic Effect of Chronic Exposure to DDT on Lymphocytes, Oral Mucosa and Breast Cells of Female Rats

    Directory of Open Access Journals (Sweden)

    Ruth De Celis

    2011-02-01

    Full Text Available The genotoxicity of some environmental contaminants may affect human health directly by damaging genetic material and thus plays an important role in cancer development. Xenoestrogens are one kind of environmental pollutants that may alter hormonal routes or directly affect DNA. The number of available biomarkers used to assess genetic risk and cancer is very extensive. The present study evaluated genotoxicity produced by the pesticide DDT on systemic and mammary gland cells obtained from adult female Wistar rats. Oral mucosa cells micronuclei were assessed; the comet assay in peripheral blood-isolated lymphocytes and mammary epithelial cells was also carried out. Additionally, oxidative stress was studied in mammary tissue through a lipid peroxidation assay. Our data showed an increase in lipid peroxidation, product of an increase in free oxygen radical levels, which leads to an oxidative stress status. Our results suggest that DDT is genotoxic, not only for lymphocytes but also to mammary epithelial cells.

  18. Genotoxic effect of chronic exposure to DDT on lymphocytes, oral mucosa and breast cells of female rats.

    Science.gov (United States)

    Canales-Aguirre, Alejandro; Padilla-Camberos, Eduardo; Gómez-Pinedo, Ulises; Salado-Ponce, Hugo; Feria-Velasco, Alfredo; De Celis, Ruth

    2011-02-01

    The genotoxicity of some environmental contaminants may affect human health directly by damaging genetic material and thus plays an important role in cancer development. Xenoestrogens are one kind of environmental pollutants that may alter hormonal routes or directly affect DNA. The number of available biomarkers used to assess genetic risk and cancer is very extensive. The present study evaluated genotoxicity produced by the pesticide DDT on systemic and mammary gland cells obtained from adult female Wistar rats. Oral mucosa cells micronuclei were assessed; the comet assay in peripheral blood-isolated lymphocytes and mammary epithelial cells was also carried out. Additionally, oxidative stress was studied in mammary tissue through a lipid peroxidation assay. Our data showed an increase in lipid peroxidation, product of an increase in free oxygen radical levels, which leads to an oxidative stress status. Our results suggest that DDT is genotoxic, not only for lymphocytes but also to mammary epithelial cells.

  19. INTERNATIONAL CONFERENCE ON HARMONISATION GUIDELINES ON THE LIMITS OF GENOTOXIC IMPURITIES IN DRUG PRODUCT

    OpenAIRE

    Malik Ajay; Thukral Kapil; Kumar Tarun; Sunil

    2012-01-01

    An impurity in a drug substance as defined by the International Conference on Harmonisation (ICH) guidelines is any component of the drug substance that is not the chemical entity defined as the drug substance. Similarly, an impurity in a drug product is any component of the drug product that is not the chemical entity defined as the drug substance or an excipient in the drug product. Genotoxic compounds have the potential to damage DNA at any level of exposure and that such damage may lead/c...

  20. Baccharis trimera (Less.) DC as genotoxicity indicator of exposure to coal and emissions from a thermal power plant.

    Science.gov (United States)

    Menezes, Ana Paula Simões; Da Silva, Juliana; Roloff, Joice; Reyes, Juliana; Debastiani, Rafaela; Dias, Johnny F; Rohr, Paula; de Barros Falcão Ferraz, Alexandre

    2013-10-01

    During coal combustion, hazardous elements are discharged that impair environmental quality. Plant cover is the first available surface for the atmospheric pollutants in terrestrial ecosystems. The aim of this study was to evaluate genotoxicity in the aqueous extract of the native plant, Baccharis trimera, exposed to coal and emissions from a thermal power plant (coal-fired power plant in Candiota, Brazil), correlating seasonality, wind tunnel predominance, and presence of inorganic elements. The presence of inorganic elements in the aerial parts of B. trimera was analyzed by particle-induced X-ray emission (PIXE) spectrometry, and genotoxicity was evaluated by ex vivo comet assay. The genotoxic effects of aqueous extracts of B. trimera from four sites located in the area around power plant were analyzed by comet assay in peripheral human lymphocytes. Winter samples showed greater levels of metals than summer samples. Genotoxicity was detected in B. trimera extracts collected from the region exposed to extraction and burning coal. Extracts from the site impacted by the dominant wind induced more damage to DNA than those from other sites. Based on our data, we can suggest that in winter the inorganic elements from extraction and burning of coal and carried through the wind tunnel were responsible for the genotoxicity observed in aqueous extract of B. trimera.

  1. Genotoxicity of citrus wastewater in prokaryotic and eukaryotic cells and efficiency of heterogeneous photocatalysis by TiO(2).

    Science.gov (United States)

    Saverini, Marghereth; Catanzaro, Irene; Sciandrello, Giulia; Avellone, Giuseppe; Indelicato, Sergio; Marcì, Giuseppe; Palmisano, Leonardo

    2012-03-01

    The presence of (±)α-pinene, (+)β-pinene, (+)3-carene, and R-(+)limonene terpenes in wastewater of a citrus transformation factory was detected and analyzed, in a previous study, by using Solid Phase Micro-extraction (SPME) followed by GC analyses. Purpose of that research was to compare the genotoxic responses of mixtures of terpenes with the genotoxicity of the individual compounds, and the biological effects of actual wastewater. Genotoxicity was evaluated in the Salmonella reversion assay (Ames test) and in V79 cells by Comet assay. Ames tests indicated that the four single terpenes did not induce an increase of revertants frequency. On the contrary, the mixtures of terpenes caused, in the presence of metabolic activation, a highly significant increase of the revertants in TA100 strain in comparison to the control. The Comet assay showed a significant increase in DNA damage in V79 cells treated for 1h with single or mixed terpenes. Moreover, the actual wastewater was found highly genotoxic in bacterial and mammalian cells. Photocatalytic tests completely photodegraded the pollutants present in aqueous wastewater and the initial high genotoxicity of samples of wastewater collected during the photocatalytic run, was completely lose in 3h of irradiation.

  2. Cytotoxic, genotoxic and apoptotic effects of naringenin-oxime relative to naringenin on normal and cancer cell lines

    Institute of Scientific and Technical Information of China (English)

    Abdurrahim Kocyigit; Ismail Koyuncu; Murat Dikilitas; Fatemeh Bahadori; Baki Turkkan

    2016-01-01

    Objective: To assess and compare the cytotoxic, genotoxic, apoptotic and reactive oxygen species (ROS) generating effects of naringenin (NG) and its new derived compound naringenin-oxime (NG-Ox) on MCF-7, HT-29, PC-12 cancer and L-929 normal cell lines. Methods: The cells were incubated with different doses of NG-Ox and NG (50–1 000 mmol/L) for 24 h. The cell viability was assessed based on ATP cell viability assay. Intracellular accumulation of ROS was determined using the fluorescent probes 2070-dichlorodihydrofluorescin diacetate. Genotoxic effects were evaluated by alkaline single cell gel electrophoresis assay (comet assay) and, the apoptotic effect was evaluated by acridine orange staining at below the IC50 levels. Results: Both NG-Ox and NG exhibited cytotoxic, genotoxic and apoptotic effects and resulted in increased ROS values in a dose-dependent manner. The effects were more pronounced on cancer cell lines. The cytotoxic, genotoxic and apoptotic effects of NG-Ox were higher than that of NG in all cell lines. Significant correlations were observed be-tween cell viability, DNA damage, apoptosis and ROS, in all cell lines exposed to either NG-Ox or NG. Conclusions: This study showed that both NG-Ox and NG possess cytotoxic, genotoxic and apoptotic activities through the production of ROS on cells, NG-Ox being the more effective one. Therefore, derived compound of NG might be used as antiproliferative agents for the treatment of cancer.

  3. Genotoxicity assessment of intravenously injected titanium dioxide nanoparticles in gpt delta transgenic mice.

    Science.gov (United States)

    Suzuki, Tetsuya; Miura, Nobuhiko; Hojo, Rieko; Yanagiba, Yukie; Suda, Megumi; Hasegawa, Tatsuya; Miyagawa, Muneyuki; Wang, Rui-Sheng

    2016-05-01

    Titanium dioxide (TiO2) nanoparticles are increasingly manufactured in large amounts for use in industrial applications such as cosmetics, pigments, foods, and as photo-catalysts. Many in vitro studies have examined the genotoxicity of TiO2 nanomaterials; some of these studies suggest that TiO2 nanoparticles (NPs) are genotoxic. Several in vivo studies have also been reported recently, but the results are inconsistent. In this study, we investigated, using several genotoxicity endpoints, the effects of dispersed TiO2 suspensions following multiple intravenous injections in mice. Male gpt Delta C57BL/6J mice were administered TiO2 NPs at doses of 2, 10 or 50mg/kg body weight per week for 4 consecutive weeks. Genotoxic effects were then analyzed by the Pig-a gene mutation assay and the micronucleus assay on peripheral blood, and by the alkaline comet, gpt mutation, and Spi(-) mutation assays on the liver. We also assessed the localization of TiO2 NPs in the liver, by transmission electron microscopy. Administration of TiO2 NPs did not significantly increase any of the following endpoints: frequency of Pig-a mutants (erythrocytes); frequency of micronuclei (reticulocytes); level of DNA damage (liver); frequencies of gpt and Spi(-) mutants (liver). Most TiO2 NPs in the liver were found in the sinuses and inside Kupffer cells, although some were occasionally observed in liver parenchymal cells. These results indicate that TiO2 NPs do not have genotoxic effects on mouse liver or bone marrow.

  4. Genotoxic effect of ethacrynic acid and impact of antioxidants

    Energy Technology Data Exchange (ETDEWEB)

    Ward, William M.; Hoffman, Jared D.; Loo, George, E-mail: g_loo@uncg.edu

    2015-07-01

    It is known that ethacrynic acid (EA) decreases the intracellular levels of glutathione. Whether the anticipated oxidative stress affects the structural integrity of DNA is unknown. Therefore, DNA damage was assessed in EA-treated HCT116 cells, and the impact of several antioxidants was also determined. EA caused both concentration-dependent and time-dependent DNA damage that eventually resulted in cell death. Unexpectedly, the DNA damage caused by EA was intensified by either ascorbic acid or trolox. In contrast, EA-induced DNA damage was reduced by N-acetylcysteine and by the iron chelator, deferoxamine. In elucidating the DNA damage, it was determined that EA increased the production of reactive oxygen species, which was inhibited by N-acetylcysteine and deferoxamine but not by ascorbic acid and trolox. Also, EA decreased glutathione levels, which were inhibited by N-acetylcysteine. But, ascorbic acid, trolox, and deferoxamine neither inhibited nor enhanced the capacity of EA to decrease glutathione. Interestingly, the glutathione synthesis inhibitor, buthionine sulfoxime, lowered glutathione to a similar degree as EA, but no noticeable DNA damage was found. Nevertheless, buthionine sulfoxime potentiated the glutathione-lowering effect of EA and intensified the DNA damage caused by EA. Additionally, in examining redox-sensitive stress gene expression, it was found that EA increased HO-1, GADD153, and p21mRNA expression, in association with increased nuclear localization of Nrf-2 and p53 proteins. In contrast to ascorbic acid, trolox, and deferoxamine, N-acetylcysteine suppressed the EA-induced upregulation of GADD153, although not of HO-1. Overall, it is concluded that EA has genotoxic properties that can be amplified by certain antioxidants. - Highlights: • Ethacrynic acid (EA) caused cellular DNA damage. • EA-induced DNA damage was potentiated by ascorbic acid or trolox. • EA increased ROS production, not inhibited by ascorbic acid or trolox. • EA

  5. Genotoxic Effects of PAH Containing Sludge Extracts in Chinese Hamster Ovary Cell Cultures

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Objective Many studies have been conducted in order to evaluate the genotoxicity of chemicals and waste materials, which utilized in vivo test protocols. The use of animals for routine toxicity testing is now questioned by a growing segment of society[1]. Methods Keeping the above fact in mind, we have conducted in the present study the genotoxicity evaluation of oily sludge samples generated from a petroleum refinery and petrochemical industry and ETP sludge from petroleum refinery using DNA damage, chromosomal aberration, p53 protein induction and apoptosis in short term in vitro mammalian Chinese Hamster Ovary cell cultures. Results It is evident from the results that the oily sludge compounds derived from petroleum refinery and petrochemical industry could cause DNA damage, chromosomal aberration, p53 protein accumulation and apoptotic cell death on exposure to oily sludge extracts in the presence of metabolic activation system (S-9 mix), however, ETP sludge extract could not cause significant genotoxicity in comparison to oily sludge extract and negative control. Conclusion The effect may be attributed to polycyclic aromatic hydrocarbons present in the samples as evidenced from GC-MS.

  6. A review of the genotoxicity of 1,2-dichloroethane (EDC).

    Science.gov (United States)

    Gwinn, Maureen R; Johns, Douglas O; Bateson, Thomas F; Guyton, Kathryn Z

    2011-01-01

    1,2-Dichloroethane (EDC, CAS#107-06-2) is a high production volume halogenated aliphatic hydrocarbon that is used mainly in the manufacture of vinyl chloride. EDC has been found in ambient and residential air samples, as well as in groundwater, surface water and drinking water. EDC has been well-studied in a variety of genotoxicity assays, and appears to involve the metabolic activation of the parent compound. We critically evaluated the genotoxicity data of EDC and its metabolites as part of an evaluation of carcinogenic mechanisms of action of EDC. EDC is genotoxic in multiple test systems via multiple routes of exposure. EDC has been shown to induce DNA adduct formation, gene mutations and chromosomal aberrations in the presence of key activation enzymes (including CYP450s and/or GSTs) in laboratory animal and in vitro studies. EDC was negative for clastogenesis as measured by the micronucleus assay in mice. In general, an increased level of DNA damage is observed related to the GSH-dependent bioactivation of EDC. Increased chromosomal aberrations with increased CYP450 expression were suggestive of a role for the oxidative metabolites of EDC in inducing chromosomal damage. Taken together, these studies demonstrate that EDC exposure, in the presence of key enzymes (including CYP450s and/or GSTs), leads to DNA adduct formation, gene mutations and chromosomal aberrations.

  7. Investigating the embryo/larval toxic and genotoxic effects of {gamma} irradiation on zebrafish eggs

    Energy Technology Data Exchange (ETDEWEB)

    Simon, O., E-mail: olivier.simon@irsn.fr [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Massarin, S. [Laboratoire de Modelisation Environnementale, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Coppin, F. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Hinton, T.G. [Service d' Etude du Comportement des Radionucleides dans les Ecosystemes, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 159, BP3, 13115 Saint-Paul-lez-Durance Cedex (France); Gilbin, R. [Laboratoire de Radioecologie et d' Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat 186, BP3, 13115 Saint-Paul-lez-Durance Cedex (France)

    2011-11-15

    Eggs/larval of freshwater fish (Danio rerio) were exposed to low dose rates of external gamma radiation (from 1 to 1000 mGy d{sup -1}) over a 20-day period, with the objective of testing the appropriateness of the 10 mGy d{sup -1} guideline suggested by the IAEA. The present study examines different endpoints, mortality and hatching time and success of embryos as well as the genotoxicity of {gamma}-irradiations (after 48 h). The 20-day embryo-larval bioassay showed an enhanced larval resistance to starvation after chronic exposure to {gamma} irradiation (from low 1 mGy d{sup -1} to high dose rate 1000 mGy d{sup -1}) and an acceleration in hatching time. Gamma irradiation led to increased genotoxic damage Ito zebrafish egg (40-50% DNA in tail in Comet assay) from the lowest dose rate (1 mGy d{sup -1}). Possible mechanisms of {gamma} radiotoxicity and implications for radioprotection are discussed. - Highlights: > Relevant information on the {gamma} radiation impact on early life stage biota is scarce. > The eggs of zebrafish Danio rerio were selected as biological model. > We test the appropriateness of the 10 mGy d{sup -1} guideline (IAEA). > We observed effects measured at individual levels (starvation, hatching time). > Chronic gamma irradiation led to increased genotoxic damage to zebrafish egg. > {gamma} radiotoxicity mechanisms and implications for radioprotection are discussed.

  8. Differential genotoxicity of diphenyl diselenide (PhSe2 and diphenyl ditelluride (PhTe2

    Directory of Open Access Journals (Sweden)

    Daiane Francine Meinerz

    2014-03-01

    Full Text Available Organoselenium compounds have been pointed out as therapeutic agents. In contrast, the potential therapeutic aspects of tellurides have not yet been demonstrated. The present study evaluated the comparative toxicological effects of diphenyl diselenide (PhSe2 and diphenyl ditelluride (PhTe2 in mice after in vivo administration. Genotoxicity (as determined by comet assay and mutagenicicity were used as end-points of toxicity. Subcutaneous administration of high doses of (PhSe2 or (PhTe2 (500 µmol/kg caused distinct genotoxicity in mice. (PhSe2 significantly decreased the DNA damage index after 48 and 96 h of its injection (p < 0.05. In contrast, (PhTe caused a significant increase in DNA damage (p < 0.05 after 48 and 96 h of intoxication. (PhSe2 did not cause mutagenicity but (PhTe2 increased the micronuclei frequency, indicating its mutagenic potential. The present study demonstrated that acute in vivo exposure to ditelluride caused genotoxicity in mice, which may be associated with pro-oxidant effects of diphenyl ditelluride. In addition, the use of this compound and possibly other related tellurides must be carefully controlled.

  9. Investigation of co-genotoxic effects of radiofrequency electromagnetic fields in vivo.

    Science.gov (United States)

    Verschaeve, L; Heikkinen, P; Verheyen, G; Van Gorp, U; Boonen, F; Vander Plaetse, F; Maes, A; Kumlin, T; Mäki-Paakkanen, J; Puranen, L; Juutilainen, J

    2006-05-01

    We investigated the possible combined genotoxic effects of radiofrequency (RF) electromagnetic fields (900 MHz, amplitude modulated at 217 Hz, mobile phone signal) with the drinking water mutagen and carcinogen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX). Female rats were exposed to RF fields for a period of 2 years for 2 h per day, 5 days per week at average whole-body specific absorption rates of 0.3 or 0.9 W/kg. MX was given in the drinking water at a concentration of 19 microg/ml. Blood samples were taken at 3, 6 and 24 months of exposure and brain and liver samples were taken at the end of the study (24 months). DNA damage was assessed in all samples using the alkaline comet assay, and micronuclei were determined in erythrocytes. We did not find significant genotoxic activity of MX in blood and liver cells. However, MX induced DNA damage in rat brain. Co-exposures to MX and RF radiation did not significantly increase the response of blood, liver and brain cells compared to MX exposure only. In conclusion, this 2-year animal study involving long-term exposures to RF radiation and MX did not provide any evidence for enhanced genotoxicity in rats exposed to RF radiation.

  10. Genotoxicity and cytotoxicity of cisplatin treatment combined with anaesthetics on EAT cells in vivo.

    Science.gov (United States)

    Brozovic, Gordana; Orsolic, Nada; Knezevic, Fabijan; Horvat Knezevic, Anica; Benkovic, Vesna; Sakic, Katarina; Hrgovic, Zlatko; Bendelja, Kreso; Fassbender, Walter J

    2009-06-01

    In this study, DNA damage in tumour cells, as well as irreversible cell damage leading to apoptosis induced in vivo by the combined application of cisplatin and inhalation anaesthetics, was investigated. The genotoxicity of anaesthetics on Ehrlich ascites tumour (EAT) cells of mice, alone or in combined application with cisplatin, was estimated by using the alkaline comet assay. The percentage of EAT cell apoptosis was quantified by flow cytometry. Groups of EAT-bearing mice were (i) treated intraperitoneally with cisplatin, (ii) exposed to repeated anaesthesia with inhalation anaesthetic, and (iii) subjected to combined treatment of exposure to anaesthetics after cisplatin for 3 days. Sevoflurane, halothane and isoflurane caused strong genotoxic effects on tumour cells in vivo. The tested anaesthetics alone showed no direct effect on programmed cell death although sevoflurane and especially halothane decreased the number of living EAT cells in peritoneal cavity lavage. Repeated anaesthesia with isoflurane had stimulatory effects on EAT cell proliferation and inhibited tumour cell apoptosis (6.11%), compared to the control group (10.26%). Cisplatin caused massive apoptosis of EAT cells (41.14%) and decreased the number of living EAT cells in the peritoneal cavity. Combined cisplatin and isoflurane treatment additionally increased EAT cell apoptosis to 51.32%. Combined treatment of mice with cisplatin and all anaesthetics increased the number of living tumour cells in the peritoneal cavity compared to cisplatin treatment of mice alone. These results suggest that the inhalation of anaesthetics may protect tumour cells from the cisplatin-induced genotoxic and cytotoxic effects.

  11. In vivo genotoxic effects of industrial waste leachates in mice following oral exposure.

    Science.gov (United States)

    Chandra, Saurabh; Chauhan, Lalit K S; Dhawan, Alok; Murthy, Ramesh C; Gupta, Shrawan K

    2006-06-01

    Contamination of ground water by industrial waste poses potential health hazards for man and his environment. The improper disposal of toxic wastes could allow genotoxic chemicals to percolate into ground waters, and these contaminated ground waters may produce toxicity, including mutation and eventually cancer, in exposed individuals. In the present study, we evaluated the in vivo genotoxic potential of leachates made from three different kinds of industrial waste (tannery waste, metal-based waste, and waste containing dyes and pigments) that are disposed of in areas adjoining human habitation. Three different doses of test leachates were administered by oral gavage for 15 consecutive days to Swiss albino mice; their bone marrow cells were examined for chromosome aberrations (CAs), micronucleated polychromatic erythrocytes (MNPCEs), and DNA damage using the alkaline Comet assay. Exposure to the leachates resulted in significant (P dye-waste leachate produced weaker genotoxic responses. The cytogenetic abnormalities and DNA damage produced by the leachates indicate that humans consuming water contaminated with these materials are at increased risk of developing adverse health consequences.

  12. The Combined Toxic and Genotoxic Effects of Cd and As to Plant Bioindicator Trifolium repens L

    Science.gov (United States)

    Ghiani, Alessandra; Fumagalli, Pietro; Nguyen Van, Tho; Gentili, Rodolfo; Citterio, Sandra

    2014-01-01

    This study was undertaken to investigate combined toxic and genotoxic effects of cadmium (Cd) and arsenic (As) on white clover, a pollutant sensitive plant frequently used as environmental bioindicator. Plants were exposed to soil spiked with increasing concentrations of cadmium sulfate (20, 40 and 60 mg Kg−1) or sodium arsenite (5, 10 and 20 mg Kg−1) as well as with their combinations. Metal(loid) bioavailability was assessed after soil contamination, whereas plant growth, metal(loid) concentration in plant organs and DNA damage were measured at the end of plant exposition. Results showed that individual and joint toxicity and genotoxicity were related to the concentration of Cd and As measured in plant organs, and that As concentration was the most relevant variable. Joint effects on plant growth were additive or synergistic, whereas joint genotoxic effects were additive or antagonistic. The interaction between Cd and As occurred at both soil and plant level. In soil the presence of As limited the bioavailability of Cd, whereas the presence of Cd increased the bioavailability of As. Nevertheless only As biovailability determined the amount of As absorbed by plants. The amount of Cd absorbed by plant was not linearly correlated with the fraction of bioavailable Cd in soil suggesting the involvement of additional factors, such as plant uptake mechanisms. These results reveal that the simultaneous presence in soil of Cd and As, although producing an additive or synergistic toxic effect on Trifolium repens L. growth, generates a lower DNA damage. PMID:24914541

  13. Genotoxicity of Microcystin-LR in In Vitro and In Vivo Experimental Models

    Directory of Open Access Journals (Sweden)

    Elsa Dias

    2014-01-01

    Full Text Available Microcystin-LR (MCLR is a cyanobacterial toxin known for its acute hepatotoxicity. Despite being recognized as tumour promoter, its genotoxicity is far from being completely clarified, particularly in organs other than liver. In this work, we used the comet and/or the micronucleus (MN assays to study the genotoxicity of MCLR in kidney- (Vero-E6 and liver-derived (HepG2 cell lines and in blood cells from MCLR-exposed mice. MCLR treatment (5 and 20 μM caused a significant induction in the MN frequency in both cell lines and, interestingly, a similar positive effect was observed in mouse reticulocytes (37.5 μg MCLR/kg, i.p. route. Moreover, the FISH-based analysis of the MN content (HepG2 cells suggested that MCLR induces both chromosome breaks and loss. On the other hand, the comet assay results were negative in Vero-E6 cells and in mouse leukocytes, with the exception of a transient increase in the level of DNA damage 30 minutes after mice exposure. Overall, the present findings contributed to increase the weight of evidence in favour of MCLR genotoxicity, based on its capacity to induce permanent genetic damage either in vitro or in vivo. Moreover, they suggest a clastogenic and aneugenic mode of action that might underlie a carcinogenic effect.

  14. Grape seed extract prevents gentamicin-induced nephrotoxicity and genotoxicity in bone marrow cells of mice.

    Science.gov (United States)

    El-Ashmawy, Ibrahim M; El-Nahas, Abeer F; Salama, Osama M

    2006-09-01

    The protection conferred by grape seed extract against gentamicin-induced nephrotoxicity and bone marrow chromosomal aberrations have been evaluated in adult Swiss albino mice. The activity of reduced glutathione peroxidase (GSH peroxidase), the levels of glutathione (GSH) and lipid peroxidation as malondialdehyde (MDA) in the kidneys homogenates, serum urea and creatinine were measured, and in addition the changes in kidney histology and bone marrow chromosomes were investigated. Gentamicin (80 mg/kg b.wt. intraperitoneally for 2 weeks) induced kidney damage as indicated from a pronounced changes in kidney histology, a significant increase in serum urea and creatinine and MDA content in the kidney homogenate. While the activity of the antioxidant enzyme GSH peroxidase and the level of GSH were significantly decreased. Gentamicin induced genotoxicity indicated by increased the number of aberrant cells and different types of structural chromosomal aberrations (fragment, deletion and ring chromosome) and showed no effect on mitotic activity of the cell. Pretreatment with grape seed extract (7 days) and simultaneously (14 days) with gentamicin significantly protected the kidney tissue by ameliorating its antioxidant activity. Moreover, grape seed extract significantly protected bone marrow chromosomes from gentamicin induced genotoxicity by reducing the total number of aberrant cells, and different types of structural chromosomal aberrations. It could be concluded that grape seed extract acts as a potent antioxidant prevented kidney damage and genotoxicity of bone marrow cells.

  15. INTERNATIONAL CONFERENCE ON HARMONISATION GUIDELINES ON THE LIMITS OF GENOTOXIC IMPURITIES IN DRUG PRODUCT

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    Malik Ajay

    2012-04-01

    Full Text Available An impurity in a drug substance as defined by the International Conference on Harmonisation (ICH guidelines is any component of the drug substance that is not the chemical entity defined as the drug substance. Similarly, an impurity in a drug product is any component of the drug product that is not the chemical entity defined as the drug substance or an excipient in the drug product. Genotoxic compounds have the potential to damage DNA at any level of exposure and that such damage may lead/contribute to tumour development. Thus for genotoxic carcinogens it is prudent to assume that there is no discernible threshold and that any level of exposure carries a risk. A threshold of toxicological concern (TTC value of 1.5μg/day intake of a genotoxic impurity is considered to be associated with an acceptable risk (excess cancer risk of <1 in 100,000 over a lifetime for most pharmaceuticals. From this threshold value, a permitted level in the active substance can be calculated based on the expected daily dose. Higher limits may be justified under certain conditions such as short-term exposure periods.

  16. Genotoxic potential of BM-21, an aqueous-ethanolic extract from Thalassia testudinum marine plant.

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    Yadira Ansoar

    2014-12-01

    Full Text Available Context: BM-21 is a hydro-ethanolic extract obtained from the leaves of Thalassia testudinum marine plant, which is rich in polyphenols, and it has demonstrated antioxidant, anti-inflammatory, cytoprotective and neuroprotective properties. Aims: To investigate the genotoxicity potential of BM-21. Methods: Salmonella typhimurium Hist. – strains were used in the pointmutation test and Escherichia coli cells were used in SOS response test. DNA primary damage was tested in hepatocytes of mice treated with oral dose of the extract (2000 mg/kg. Bone marrow micronucleus assay was used in mice to detect clastogenic damage while serum from the same animals was used to determine MDA levels in order to find out the influence of BM-21 on lipid peroxidation. Positive and negative controls were included in all experimental series. Results: BM-21 did not increase the frequency of reverse mutations in the Ames test, and it did not induce primary damage in E. coli. Comet assay showed that 2 000 mg/kg of BM-21 induced single strand breaks or alkali-labile sites in the hepatocytes from the treated mice. However, no increase in the micronucleus frequency was observed in mice polychromatic erythrocytes and significantly reduced MDA levels were detected. Conclusions: BM-21 was neither mutagenic nor induces DNA damage to prokaryotic cells. Although, it increased DNA strand breaks in vivo, this one was not translated into clastogenic damage to the whole organism. Results suggested that BM-21 was not mutagenic or genotoxic under our experimental conditions.

  17. Genotoxicity assessment of 4-methylimidazole: regulatory perspectives.

    Science.gov (United States)

    Morita, Takeshi; Uneyama, Chikako

    2016-01-01

    4-Methylimidazole (4-MI) is formed as a result of the Maillard reaction process, and therefore is found in many foods and beverages. It is also found in soft drinks (i.e., cola) as a by-product in the production of some caramel colors. NTP bioassays revealed clear evidence of lung carcinogenicity of 4-MI in male and female mice, but not in rats and then IARC classified 4-MI as group 2B carcinogen. Genotoxicity studies with 4-MI were negative in the Ames tests and in the erythrocyte micronucleus tests with mice or rats. US California EPA (CEPA) evaluated the testing has not been adequately comprehensive to rule out a genotoxic mode of action; as target tissue of the carcinogenicity of 4-MI was lung, the lung should be used as a source tissue for in vitro metabolic activation system. Thus, CEPA defined the No Significant Risk Level (NSRL) for 10(-5) lifetime risk level of cancer by 4-MI as 29 μg/day based on the non-threshold approach. As higher levels of 4-MI than the NSRL were identified in some kinds of cola, health concerns of 4-MI were drawn the attention. On the other hand, other regulatory bodies (e.g., European Food Safety Authority, EFSA) showed no concerns of 4-MI from the use of caramel colors in food. EFSA evaluated 4-MI is not genotoxic, so, non-observed adverse effect level of 4-MI was considered to be 80 mg/kg/day. In this paper, genotoxic assessments of 4-MI in different regulatory bodies are presented and the risk evaluation of 4-MI is discussed based on new genotoxicity data.

  18. Acute effects of a prooxidant herbicide on the microalga Chlamydomonas reinhardtii: Screening cytotoxicity and genotoxicity endpoints

    Energy Technology Data Exchange (ETDEWEB)

    Esperanza, Marta; Cid, Ángeles; Herrero, Concepción; Rioboo, Carmen, E-mail: carmen.rioboo@udc.es

    2015-08-15

    Highlights: • Mitochondrial membrane potential constituted the most sensitive parameter assayed. • Several genotoxicity methods were applied for first time in ecotoxicological studies. • Oxidative DNA base damage (8-OHdG) was induced by paraquat exposure. • Cells with DNA strand breakage and subG1-nuclei increased in treated cultures. • Typical apoptosis hallmarks were observed in microalgal cells exposed to paraquat. - Abstract: Since recent evidence has demonstrated that many types of chemicals exhibit oxidative and/or genotoxic potential on living organisms, reactive oxygen species (ROS) formation and DNA damage are currently the best accepted paradigms to assess the potential hazardous biological effects of a wide range of contaminants. The goal of this study was to evaluate the sensitivity of different cytotoxicity and genotoxicity responses on the model microalga Chlamydomonas reinhardtii exposed to the prooxidant herbicide paraquat. In addition to the growth endpoint, cell viability, mitochondrial membrane potential and presence of reactive oxygen species (ROS) were assayed as potential markers of cytotoxicity using flow cytometry (FCM). To study the effects of paraquat on C. reinhardtii DNA, several genotoxicity approaches were implemented for the first time in an ecotoxicological study on microalgae. Oxidative DNA base damage was analysed by measuring the oxidative DNA lesion 8-OHdG by FCM. DNA fragmentation was analysed by different methods: comet assay, and cell cycle analysis by FCM, with a particular focus on the presence of subG1-nuclei. Finally, effects on morphology of nuclei were monitored through DAPI staining. The evaluation of these endpoints showed that several physiological and biochemical parameters reacted to oxidative stress disturbances with greater sensitivity than integrative parameters such as growth rates or cell viability. The experiments revealed concentration-dependent cytotoxicity (ROS formation, depolarization of

  19. Genotoxic testing of titanium dioxide anatase nanoparticles using the wing-spot test and the comet assay in Drosophila.

    Science.gov (United States)

    Carmona, Erico R; Escobar, Bibi; Vales, Gerard; Marcos, Ricard

    2015-01-15

    Titanium dioxide nanoparticles (TiO2 NPs) are widely used for preparations of sunscreens, cosmetics, food and personal care products. However, the possible genotoxic risk associated with this nano-scale material exposure is not clear, especially in whole organisms. In the present study, we explored the in vivo genotoxic activity of TiO2 NPs as well as their TiO2 bulk form using two well-established genotoxic assays, the wing spot test and the comet assay in Drosophila melanogaster. To determine the extent of tissue damage induced by TiO2 NPs in Drosophila larvae, the trypan blue dye exclusion test was also applied. Both compounds were supplied to third instar larvae by ingestion at concentration ranging from 0.08 to 1.60 mg/mL. The results obtained in the present study indicate that TiO2 NPs can reach and induce cytotoxic effects on midgut and imaginal disc tissues of larvae, but they do not promote genotoxicity in the wing-spot test of Drosophila. However, when both nano- and large-size forms of TiO2 were evaluated with the comet assay in Drosophila hemocytes, a significant increase in DNA damage, with a direct dose-response pattern, was observed for TiO2 NPs. The results obtained with the comet assay suggest that the primary DNA damage associated with TiO2 NPs exposure in Drosophila could be associated with specific physico-chemical properties of nano-TiO2, since no effects were observed with the bulk form. This study remarks the usefulness of using more than one genetic end-point in the evaluation of the genotoxic potential of nanomaterials.

  20. Evaluation of the genotoxic and mutagenic potentials of phytotherapic and homeopathic solutions of Euphorbia tirucalli Lineu (Aveloz

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    Carla Holandino

    2011-07-01

    Full Text Available Introduction: Euphorbia tirucalli Lineu, commonly known as Aveloz, is a very common plant found in tropical regions [1]. The ingestion or contact with its latex causes symptoms such as vomiting and diarrhea, pallor, skin irritation, hepatotoxicity as well as carcinogenesis [2]. Moreover, the Aveloz latex is also responsible for a few important activities against some infectious and neoplastic diseases. Aveloz latex phytochemical composition may vary according to seasonal aspects and geographic location [3], and it is used either orally or topically in traditional medicine. Popularly known as an antitumoral agent (breast, prostate, lung, kidney, it is used not only in Brazil, but in several other countries. According to the literature, the latex could have a dual behaviour, activating or inhibiting tumoral events [3-6]. However, there are few reports discussing these mechanisms. Besides, the mutagenic and genotoxic potentials of phytochemical and homeopathic Aveloz have not yet been described. Several experimental methods have been used to evaluate the mutagenic and genotoxic effects, such as Inductest, the Ames test and the chromotest. Objective: This study aims to evaluate the genotoxic and mutagenic potentials of Aveloz latex and Aveloz phytotherapic and homeopathic solutions. Methodology: In this study, Aveloz 5 and 30cH are prepared according to Brazilian Homeopathic Pharmacopoeia [7], from Aveloz latex collected in the Center for Natural Products Research (NPPN at the Universidade Federal do Rio de Janeiro [8]. The Aveloz phytochemical solution was prepared following the doses used in folk medicine: 2 drops diluted in 250ml of water and 2 drops diluted in 25 ml of water. All test solutions were submitted to the following methodologies: (a Inductest: assesses the ability of physical or chemical agents to promote lysogenic induction as a response to DNA damage in lysogenic bacteria; (b The Ames test: uses indicator strains of Salmonella

  1. Assessment of the in vivo genotoxicity of cadmium chloride, chloroform, and D,L-menthol as coded test chemicals using the alkaline comet assay.

    Science.gov (United States)

    Wada, Kunio; Fukuyama, Tomoki; Nakashima, Nobuaki; Matsumoto, Kyomu

    2015-07-01

    As part of the Japanese Center for the Validation of Alternative Methods (JaCVAM) international validation study of in vivo rat alkaline comet assays, we examined cadmium chloride, chloroform, and D,L-menthol under blind conditions as coded chemicals in the liver and stomach of Sprague-Dawley rats after 3 days of administration. Cadmium chloride showed equivocal responses in the liver and stomach, supporting previous reports of its poor mutagenic potential and non-carcinogenic effects in these organs. Treatment with chloroform, which is a non-genotoxic carcinogen, did not induce DNA damage in the liver or stomach. Some histopathological changes, such as necrosis and degeneration, were observed in the liver; however, they did not affect the comet assay results. D,L-Menthol, a non-genotoxic non-carcinogen, did not induce liver or stomach DNA damage. These results indicate that the comet assay can reflect genotoxic properties under blind conditions.

  2. Comet Assay on Daphnia magna in eco-genotoxicity testing.

    Science.gov (United States)

    Pellegri, Valerio; Gorbi, Gessica; Buschini, Annamaria

    2014-10-01

    Detection of potentially hazardous compounds in water bodies is a priority in environmental risk assessment. For the evaluation and monitoring of water quality, a series of methodologies may be applied. Among them, the worldwide used toxicity tests with organisms of the genus Daphnia is one of the most powerful. In recent years, some attempts were made to utilize Daphnia magna in genotoxicity testing as many of the new environmental contaminants are described as DNA-damaging agents in aquatic organisms. The aim of this research was to develop a highly standardized protocol of the Comet Assay adapted for D. magna, especially regarding the isolation of cells derived from the same tissue (haemolymph) from newborn organisms exposed in vivo. Several methods for haemolymph extraction and different Comet Assay parameters were compared. Electrophoretic conditions were adapted in order to obtain minimum DNA migration in cells derived from untreated organisms and, at the same time, maximum sensitivity in specimens treated with known genotoxicants (CdCl2 and H2O2). Additional tests were performed to investigate if life-history traits of the cladoceran (such as the age of adult organisms that provide newborns, the clutch size of origin, the number of generations reared in standard conditions) and the water composition as well, might influence the response of the assay. This study confirms the potential application of the Comet Assay in D. magna for assessing genotoxic loads in aqueous solution. The newly developed protocol could integrate the acute toxicity bioassay, thus expanding the possibility of using this model species in freshwater monitoring (waters, sediment and soil elutriates) and is in line with the spirit of the EU Water Framework Directive in reducing the number of bioassays that involve medium-sized species.

  3. Genotoxic effects of fumes from asphalt modified with waste plastic and tall oil pitch.

    Science.gov (United States)

    Lindberg, Hanna K; Väänänen, Virpi; Järventaus, Hilkka; Suhonen, Satu; Nygren, Jonas; Hämeilä, Mervi; Valtonen, Jarkko; Heikkilä, Pirjo; Norppa, Hannu

    2008-05-31

    As the use of recycled materials and industrial by-products in asphalt mixtures is increasing, we investigated if recycled additives modify the genotoxicity of fumes emitted from asphalt. Fumes were generated in the laboratory at paving temperature from stone-mastic asphalt (SMA) and from SMA modified with waste plastic (90% polyethylene, 10% polypropylene) and tall oil pitch (SMA-WPT). In addition, fumes from SMA, SMA-WPT, asphalt concrete (AC), and AC modified with waste plastic and tall oil pitch (AC-WPT) were collected at paving sites. The genotoxicity of the fumes was studied by analysis of DNA damage (measured in the comet assay) and micronucleus formation in human bronchial epithelial BEAS 2B cells in vitro and by counting mutations in Salmonella typhimurium strains TA98 and YG1024. DNA damage was also assessed in buccal leukocytes from road pavers before and after working with SMA, SMA-WPT, AC, and AC-WPT. The chemical composition of the emissions was analysed by gas chromatography/mass spectrometry. The SMA-WPT fume generated in the laboratory induced a clear increase in DNA damage in BEAS 2B cells without metabolic activation. The laboratory-generated SMA fume increased the frequency of micronucleated BEAS 2B cells without metabolic activation. None of the asphalt fumes collected at the paving sites produced DNA damage with or without metabolic activation. Fumes from SMA and SMA-WPT from the paving sites increased micronucleus frequency without metabolic activation. None of the asphalt fumes studied showed mutagenic activity in Salmonella. No statistically significant differences in DNA damage in buccal leukocytes were detected between the pre- and post-shift samples collected from the road pavers. However, a positive correlation was found between DNA damage and the urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) after work shift, which suggested an association between occupational exposures during road paving and genotoxic effects. Our

  4. Fecal water genotoxicity is predictive of tumor-preventive activities by inulin-like oligofructoses, probiotics (Lactobacillus rhamnosus and Bifidobacterium lactis), and their synbiotic combination.

    Science.gov (United States)

    Klinder, Annett; Förster, Antje; Caderni, Giovanna; Femia, Angelo Pietro; Pool-Zobel, Beatrice L

    2004-01-01

    The measurement of fecal water genotoxicity in human colon cells could be a useful biomarker to study effects of diet in the colon. Here we assessed aqueous fecal extracts of samples from a chronic study with rats fed prebiotics, probiotics, and their combination. Treatments were maltodextrins (controls), inulin/oligofructoses (prebiotic), Lactobacillus rhamnosus, and Bifidobacterium lactis (probiotics) or both (synbiotic). Azoxymethane (AOM) was administered to initiate tumors. Rat feces were collected at 0 and 10 days and 2, 4, and 8 mo, and cecal contents were collected at 8 mo. Aqueous phases were prepared and tested for genotoxicity in HT29 colon cells using the comet assay. The studied types of intervention reduced fecal and cecal genotoxicity. DNA damage by samples from AOM-treated, tumor-free rats was significantly lower than from tumor-bearing animals, especially after 4 mo of synbiotic and prebiotic interventions. Inulin-based diets reduced exposure to genotoxins in the feces, directly reflecting the reported reduction of tumor incidence in these animals. Evidence is provided for the validity of this measurement as a biomarker of chemoprevention because 1) fecal water genotoxicity reflected genotoxic exposure in the cecum, 2) tumor incidence and fecal genotoxicity were directly related, and 3) these interventions reduced tumor risks by reducing exposure to genotoxins in the gut.

  5. In Vitro Analysis of Early Genotoxic and Cytotoxic Effects of Okadaic Acid in Different Cell Types of the Mussel Mytilus galloprovincialis.

    Science.gov (United States)

    Prego-Faraldo, María Verónica; Valdiglesias, Vanessa; Laffon, Blanca; Eirín-López, José M; Méndez, Josefina

    2015-01-01

    Okadaic acid (OA) is the predominant biotoxin responsible for diarrhetic shellfish poisoning (DSP) syndrome in humans. While its harmful effects have been extensively studied in mammalian cell lines, the impact on marine organisms routinely exposed to OA is still not fully known. Few investigations available on bivalve molluscs suggest less genotoxic and cytotoxic effects of OA at high concentrations during long exposure times. In contrast, no apparent information is available on how sublethal concentrations of OA affect these organisms over short exposure times. In order to fill this gap, this study addressed for the first time in vitro analysis of early genotoxic and cytotoxic effects attributed to OA in two cell types of the mussel Mytilus galloprovincialis. Accordingly, hemocytes and gill cells were exposed to low OA concentrations (10, 50, 100, 200, or 500 nM) for short periods of time (1 or 2 h). The resulting DNA damage, as apoptosis and necrosis, was subsequently quantified using the comet assay and flow cytometry, respectively. Data demonstrated that (1) mussel hemocytes seem to display a resistance mechanism against early genotoxic and cytotoxic OA-induced effects, (2) mussel gill cells display higher sensitivity to early OA-mediated genotoxicity than hemocytes, and (3) mussel gill cells constitute more suitable systems to evaluate the genotoxic effect of low OA concentrations in short exposure studies. Taken together, this investigation provides evidence supporting the more reliable suitability of mussel gill cells compared to hemocytes to evaluate the genotoxic effect of low short-duration exposure to OA.

  6. Comparative evaluation of genotoxicity of captan in amphibian larvae (Xenopus laevis and Pleurodeles waltl) using the comet assay and the micronucleus test.

    Science.gov (United States)

    Mouchet, F; Gauthier, L; Mailhes, C; Ferrier, V; Devaux, A

    2006-06-01

    Captan (N-trichloromethylthio-4-cyclohexene-1,2-dicarboximide) is a fungicide used to inhibit the growth of many types of fungi on plants used as foodstuffs. The toxic and genotoxic potentials of captan were evaluated with the micronucleus test (MNT; AFNOR,2000) and the comet assay (CA) using amphibian larvae (Xenopus laevis and Pleurodeles waltl). Acute toxicity results showed that captan was toxic (1) to Xenopus larvae exposed to from 2 mg/L to 125 or 62.5 microg/L, depending on the nature of the water [reconstituted water containing mineral salts or mineral water (MW; Volvic, Danone, France)] and (2) to Pleurodeles exposed to from 2 mg/L to 125 microg/L in both types of water. The MNT results obtained in MW showed that captan (62.5 microg/L) was genotoxic to Xenopus but not genotoxic to Pleurodeles at all concentrations tested. CA established that the genotoxicity of captan to Xenopus and Pleurodeles larvae depended on the concentration, the exposure times, and the comet parameters (tail DNA, TEM, OTM, and TL). The CA and MNT results were compared for their ability to detect DNA damage at the concentrations of captan and the exposure times applied. CA showed captan to be genotoxic from the first day of exposure. In amphibians, CA appears to be a sensitive and suitable method for detecting genotoxicity such as that caused by captan.

  7. GENOTOXICITY OF SHALLOW WATERS NEAR THE BRAZILIAN ANTARCTIC STATION "COMANDANTE FERRAZ" (EACF, ADMIRALTY BAY, KING GEORGE ISLAND, ANTARCTICA

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    Arthur José da Silva Rocha

    2015-03-01

    Full Text Available Series of biomonitoring surveys were undertaken weekly in February 2012 to investigate the genotoxicity of the shallow waters around the Brazilian Antarctic Station "Comandante Ferraz" (EACF. The comet assay was applied to assess the damage to the DNA of hemocytes of the crustacean amphipods Gondogeneia antarctica collected from shallow waters near the Fuel Tanks (FT and Sewage Treatment Outflow (STO of the research station, and compare it to the DNA damage of animals from Punta Plaza (PPL and Yellow Point (YP, natural sites far from the EACF defined as experimental controls. The damage to the DNA of hemocytes of G. antarctica was not significantly different between sites in the biomonitoring surveys I and II. In survey III, the damage to the DNA of animals captured in shallow waters near the Fuel Tanks (FT and Sewage Treatment Outflow (STO was significantly higher than that of the control site of Punta Plaza (PPL. In biomonitoring survey IV, a significant difference was detected only between the FT and PPL sites. Results demonstrated that the shallow waters in front of the station may be genotoxic and that the comet assay and hemocytes of G. antarctica are useful tools for assessing genotoxicity in biomonitoring studies of Antarctic marine coastal habitats.

  8. Application of the Single Cell Gel Electrophoresis (SCGE) Assay to Genotoxicity Evaluation in Plants and Animals

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Kyu

    2007-10-15

    Application of the Single Cell Gel Electrophoresis (SCGE) Assay to Genotoxicity Evaluation in Plants and Animals. Recently, the importance of ionizing radiation and chemicals has been recognized since radio- and chemical therapy is directly related to the control of various diseases such as cancer. Radiation and the chemicals can cause biological damages while they have great applicability. It is of necessity to analyze rapidly, easily and accurately the biological effects, especially DNA damage due to those factors. Recently SCGE (single cell gel electrophoresis assay, alias comet assay) has been developed for the efficient evaluation of DNA damage. In this report, the comprehensive review will be given on the rationale, the technical applications and the advantages and shortcomings of SCGE assay. This method can be directly applied to study on toxicity, cancer, and aging in terms of the evaluation of DNA damages due to radiation and chemicals on human cellular level. It is also suggested that comet assay be used for testing genotoxicity of suspected substances, detecting irradiated foods, screening radioprotective candidates, and studying DNA repair process in various biological systems.

  9. Protective Effect of Onion Extract on Bleomycin-Induced Cytotoxicity and Genotoxicity in Human Lymphocytes

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    Yoon Hee Cho

    2016-02-01

    Full Text Available Following one of the world’s largest nuclear accidents, occured at Fukushima, Japan in 2011, a significant scientific effort has focused on minimizing the potential adverse health effects due to radiation exposure. The use of natural dietary antioxidants to reduce the risk of radiation-induced oxidative DNA damage is a simple strategy for minimizing radiation-related cancer rates and improving overall health. The onion is among the richest sources of dietary flavonoids and is an important food for increasing their overall intake. Therefore, we examined the effect of an onion extract on cyto- and geno-toxicity in human lymphocytes treated with bleomycin (BLM, a radiomimetic agent. In addition, we measured the frequency of micronuclei (MN and DNA damage following treatment with BLM using a cytokinesis-blocked micronucleus assay and a single cell gel electrophoresis assay. We observed a significant increase in cell viability in lymphocytes treated with onion extract then exposed to BLM compared to cells treated with BLM alone. The frequency of BLM induced MN and DNA damage increased in a dose-dependent manner; however, when lymphocytes were pretreated with onion extract (10 and 20 μL/mL, the frequency of BLM-induced MN was decreased at all doses of BLM and DNA damage was decreased at 3 μg/mL of BLM. These results suggest that onion extract may have protective effects against BLM-induced cyto- and genotoxicity in human lymphocytes.

  10. Comet Assay: A Method to Evaluate Genotoxicity of Nano-Drug Delivery System

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    Morteza Eskandani

    2011-08-01

    Full Text Available Introduction: Drug delivery systems could induce cellular toxicity as side effect of nanomaterials. The mechanism of toxicity usually involves DNA damage. The comet assay or single cell gel electrophoresis (SCGE is a sensitive method for detecting strand damages in the DNA of a cell with applications in genotoxicity testing and molecular epidemiology as well as fundamental research in DNA damage and repair. Methods: In the current study, we reviewed recent drug delivery researches related to SCGE. Results: We found that one preference for choosing the assay is that comet images may result from apoptosis-mediated nuclear fragmentation. This method has been widely used over the last decade in several different areas. Overall cells, such as cultured cells are embedded in agarose on a microscope slide, lysed with detergent, and treated with high salt. Nucleoids are supercoiled DNA form. When the slide is faced to alkaline electrophoresis any breakages present in the DNA cause the supercoiling to relax locally and loops of DNA extend toward the anode as a ‘‘comet tail’’. Conclusion: This article provides a relatively comprehensive review upon potentiality of the comet assay for assessment of DNA damage and accordingly it can be used as an informative platform in genotoxicity studies of drug delivery systems.

  11. Analysis of the genotoxic potential of low concentrations of Malathion on the Allium cepa cells and rat hepatoma tissue culture.

    Science.gov (United States)

    Bianchi, Jaqueline; Mantovani, Mario Sérgio; Marin-Morales, Maria Aparecida

    2015-10-01

    Based on the concentration of Malathion used in the field, we evaluated the genotoxic potential of low concentrations of this insecticide on meristematic and F1 cells of Allium cepa and on rat hepatoma tissue culture (HTC cells). In the A. cepa, chromosomal aberrations (CAs), micronuclei (MN), and mitotic index (MI) were evaluated by exposing the cells at 1.5, 0.75, 0.37, and 0.18mg/mL of Malathion for 24 and 48hr of exposure and 48hr of recovery time. The results showed that all concentrations were genotoxic to A. cepa cells. However, the analysis of the MI has showed non-relevant effects. Chromosomal bridges were the CA more frequently induced, indicating the clastogenic action of Malathion. After the recovery period, the higher concentrations continued to induce genotoxic effects, unlike the observed for the lowest concentrations tested. In HTC cells, the genotoxicity of Malathion was evaluated by the MN test and the comet assay by exposing the cells at 0.09, 0.009, and 0.0009mg/5mL culture medium, for 24hr of exposure. In the comet assay, all the concentrations induced genotoxicity in the HTC cells. In the MN test, no significant induction of MN was observed. The genotoxicity induced by the low concentrations of Malathion presented in this work highlights the importance of studying the effects of low concentrations of this pesticide and demonstrates the efficiency of these two test systems for the detection of genetic damage promoted by Malathion.

  12. Mechanisms of genotoxic effects of hormones

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    Đelić Ninoslav J.

    2002-01-01

    Full Text Available A concept that compounds commonly present in biological systems lack genotoxic and mutagenic activities is generally in use, hence a low number of endogenous substances have ever been tested to mutagenicity. Epidemiological and experimental analyses indicated, however, that sexual steroids could contribute to initiation and/or continuation of malign diseases. Detailed studies using methods of biochemistry, molecular biology, cytogenetics and other branches, showed that not only epigenetic mechanisms, such as a stimulation of cell proliferation, but also certain hormones, that can express genotoxic effects, such as covalent DNA modification, then chromosomal lesions and chromosomal aberrations, are in the background of malign transformation under activities of hormones. In the case of oestrogens, it was shown that excessive hormonal stimulation led to a metabolic conversion of these hormones to reactive intermediates with formation of reactive oxygenic derivates, so that cells were virtually under conditions of oxidative stress. Individual and tissue susceptibility to occurrence of deterioration of DNA and other cell components generally results from the differences in efficiency of enzymic and non-enzymic mechanisms of resistance against oxidative stress. Besides, steroid thyeroid hormones and catecholamine (dopamine, noradrenaline/norepinephrine and adrenaline can express genotoxic effects in some test-systems. It is interesting that all above mentioned hormones have a phenolic group. Data on possible genotoxic effects of peptide and protein hormones are very scarce, but based on the available literature it is considered that this group of hormones probably lacks mutagenic activities. The possibility that hormones, as endogenous substances, express mutagenic activities results from the fact that DNA is, regardless of chemical and metabolic stability susceptible, to a certain extent, to changeability compatible with the processes of the

  13. Genotoxic effects of copper sulfate in rabbits

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    Georgieva S.

    2013-01-01

    Full Text Available This study was carried out to determine the genotoxic effects of oral application of CuSO4 in rabbits by the chromosome aberration (CA and sister chromatid exchange (SCE tests. Ten male New Zealand rabbits (5 months old, weighing 3.5-4.0 kg were allocated into two groups. The first group received CuSO4 (5H2O in drinking water for 6 consecutive days. The second group was used as a control. On the 7th day, blood samples were taken from the ear marginal vein and the SCE and CA tests in peripheral lymphocytes were used as genotoxicity and mutagenicity endpoints, respectively. Results showed a significant increase in the frequencies of the aberrant cells (7.4±0.24, P<0.001 and CA (chromatid fragments 3.2±0.37, chromosome fragments 4.2±0.37, P<0.001, and total aberrations (7.4±0.24, P<0.001 after the treatment with CuSO4 when compared with the control group. The level of SCE per cell in the CuSO4-treated rabbits (9.66±0.062 was significantly higher than in rabbits from the control group. These findings show that copper exhibits a genotoxic and mutagenic potential in rabbits.

  14. Cytotoxicity and genotoxicity of biogenic silver nanoparticles

    Science.gov (United States)

    Lima, R.; Feitosa, L. O.; Ballottin, D.; Marcato, P. D.; Tasic, L.; Durán, N.

    2013-04-01

    Biogenic silver nanoparticles with 40.3 ± 3.5 nm size and negative surface charge (- 40 mV) were prepared with Fusarium oxysporum. The cytotoxicity of 3T3 cell and human lymphocyte were studied by a TaliTM image-based cytometer and the genotoxicity through Allium cepa and comet assay. The results of BioAg-w (washed) and BioAg-nw (unwashed) biogenic silver nanoparticles showed cytotoxicity exceeding 50 μg/mL with no significant differences of response in 5 and 10 μg/mL regarding viability. Results of genotoxicity at concentrations 5.0 and 10.0 ug/mL show some response, but at concentrations 0.5 and 1.0 μg/mL the washed and unwashed silver nanoparticles did not present any effect. This in an important result since in tests with different bacteria species and strains, including resistant, MIC (minimal inhibitory concentration) had good answers at concentrations less than 1.9 μg/mL. This work concludes that biogenic silver nanoparticles may be a promising option for antimicrobial use in the range where no cyto or genotoxic effect were observed. Furthermore, human cells were found to have a greater resistance to the toxic effects of silver nanoparticles in comparison with other cells.

  15. From nanotechnology to nanogenotoxicology: genotoxic effect of cobalt-chromium nanoparticles

    Directory of Open Access Journals (Sweden)

    Zülal Atlı Şekeroğlu

    2013-03-01

    Full Text Available Nanotechnology is a multi-disciplinary technology that processes the materials that can be measured with nanometer-level and combines many research field or discipline. Nanomaterials (NMs are widely used in the fields of science, technology, communication, electronics, industry, pharmacy, medicine, environment, consumer products and military. Until recently little has been known about whether or not nanomaterials have the toxic or hazardous effects on human health and the environment. However, several studies have indicated that exposure to some nanomaterials, e.g. nanoparticles, can cause some adverse effects in humans and animals. Over the last years the number of publications focusing on nanotoxicology has gained momentum, but, there is still a gap about the genotoxicity of nanomaterials.Metal nanoparticles and their alloys with excellent mechanical properties are the materials which can be easily adapted to the mechanical conditions of the musculoskeletal system. Cobalt-chromium alloys are widely used in orthopedic applications as joint prosthesis and bone regeneration material, fillings and dental implants in jaw surgery, and in cardiovascular surgery, especially stent applications. Studies about cytotoxicity and genotoxicity of metal nanoparticles on human indicate that some metal nanoparticles have cytotoxic and genotoxic effects and they may be hazardous for humans. However, a few studies have been reported concerning the genotoxic effects of cobalt-chromium nanoparticles. The data from these studies indicate that cobalt-chromium nanoparticles have cytotoxic and genotoxic effects. It has been stated that the wear debris from implants cause DNA and chromosome damage in patients with cobalt-chromium replacements. It was also found that the risk of urinary cancers such as bladder, ureter, kidney and prostate in patients after hip replacement than among the wider population.Because there are very little biocompatibility and toxicity tests on

  16. Genotoxic activity of a technical toxaphene mixture and its photodegradation products in SOS genotoxicity tests.

    Science.gov (United States)

    Bartos, Tomás; Skarek, Michal; Cupr, Pavel; Kosubová, Petra; Holoubek, Ivan

    2005-01-03

    Toxaphene (CAS No. 800-35-2) is a complex mixture of several hundred components that was used worldwide primarily as an agricultural pesticide with insecticide effects in the second half of the 20th century. In vitro investigations of the genotoxicity and mutagenicity of toxaphene were generally described in the literature, but they provided somewhat equivocal results. We re-evaluated the genotoxicity of technical toxaphene in two prokaryotic systems. The SOS Chromotest showed high sensitivity to toxaphene: three concentrations (40, 20 and 10 mg/l) were clearly positive and the dose-response effect was evident. In the umuC assay, a dose-dependent increase in genotoxic activity was observed at toxaphene concentrations from 2.5 to 40.0 mg/l, but these results were found to be not significant. The genotoxicity of toxaphene and its photodegradation products after UV-irradiation (3-6-9 h) at concentrations ranging from 7.5 to 60.0 mg/l was also examined in this study. An irradiated solution of technical toxaphene after 3 h showed no significant evidence of bacterial growth inhibition. However, exposure of Salmonella to 6 h UV-irradiated toxaphene showed a toxic effect compared with the negative control. After 9 h irradiation, a decrease of bacterial growth was observed. Activity of beta-galactosidase in the presence of a toxaphene solution was significantly increased after 6 and 9 h irradiation, reaching values that were 2.4- and 3.1-fold higher, respectively, than the control, which exceeded the criteria of significant genotoxicity. These results show that while technical toxaphene is a weak, direct-acting mutagen in some bacterial tests, a dose-dependent toxicity and genotoxicity of its photoproducts could be conclusively demonstrated by the umuC test.

  17. Evaluation of Hypoglycemic and Genotoxic Effect of Polyphenolic Bark Extract from Quercus sideroxyla

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    Marcela Soto-García

    2016-01-01

    Full Text Available Quercus sideroxyla is a wood species whose bark has phenolic compound and should be considered to be bioactive; the hypoglycemic and genotoxic properties of Q. sideroxyla bark were evaluated in this study. Total phenolic compound was determined in crude extract (CE and organic extract (OE. The OE has the highest amount of phenols (724.1±12.0 GAE/g. Besides, both CE and OE demonstrated effect over the inhibition of α-amylase in vitro. Hypoglycemic activity was assessed by glucose tolerance curve and the area under curve (UAC; OE showed the highest hypoglycemic activity. In addition, diabetes was induced by streptozotocin (65 mg/kg and the extracts (50 mg/kg were administered for 10 days; OE showed hypoglycemic effect compared with diabetic control and decreased hepatic lipid peroxidation. Acute toxicity and genotoxicity were evaluated in CE; results of acute toxicity did not show any mortality. Besides, the comet assay showed that CE at a dose of 100 mg/kg did not show any genotoxic effect when evaluated at 24 h, whereas it induced slight damage at 200 mg/kg, with the formation of type 1 comets.

  18. Methodological considerations for using umu assay to assess photo-genotoxicity of engineered nanoparticles

    DEFF Research Database (Denmark)

    Cupi, Denisa; Baun, Anders

    2016-01-01

    In this study we investigated the feasibility of high-throughput (96-well plate) umu assay to test the genotoxic effect of TiO2 engineered nanoparticles (ENPs) under UV light (full spectrum) and visible light (455nm). Exposure of TiO2 ENPs to up to 60min of UV light induced a photocatalytic...... production of ROS. However, UV light itself caused cytotoxic damage to Salmonella typhimurium at exposures >15min and a genotoxic effect at exposures >0.5min; and use of UV filters did not lower this effect. No genotoxicity of TiO2 ENPs was observed under visible light conditions at concentrations up to 100......μgmL(-1); or under dark conditions at concentrations up to 667μgmL(-1), though cytotoxicity was seen at the higher concentrations. Additionally, the growth factor calculation was influenced by a shading effect due to ENPs, and was corrected by considering the pre-incubation OD readings of Plate B...

  19. Zebrafish as an in vivo high-throughput model for genotoxicity.

    Science.gov (United States)

    Chakravarthy, Sridhara; Sadagopan, Sathish; Nair, Ayyappan; Sukumaran, Sunil Kumar

    2014-04-01

    Compounds routinely used to increase the quality of life and combat disease undergo stringent potency and biosafety tests before approval. However, based on the outcome of ongoing research, new norms need to be effected to ensure that the compounds conform to biosafety at all target levels of activity. Whereas in vitro tests used to assess biosafety lack the potency and the translational attribute of a whole animal, mammalian preclinical models are expensive and time exhaustive. Zebrafish (Danio rerio) has emerged as an attractive alternative for biosafety studies due to its small size, genetics, breeding capabilities, and most importantly, similarity at the molecular and physiological levels with humans. It has been used extensively for testing various forms of toxicity, including developmental toxicity, cardiotoxicity, nephrotoxicity, and hepatotoxicity. We review here the utility of zebrafish as a powerful, sensitive, quantitative, noninvasive, and high-throughput whole-animal assay to screen for toxicity. Different forms of toxicity will be discussed briefly before we highlight the present state of genotoxicity study in zebrafish. This review, a first in this research area, will serve as a comprehensive introduction to the field of genotoxicity assay using zebrafish, a nascent but promising field that assays compounds for DNA damage. We also discuss possible approaches that could potentially be pursued to overcome some of the shortcomings in current genotoxic studies.

  20. Evaluation of genotoxicity induced by repetitive administration of local anaesthetics: an experimental study in rats

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    Gisele Alborghetti Nai

    2015-02-01

    Full Text Available BACKGROUND AND OBJECTIVE: Previous studies regarding the effects of some local anaesthetics have suggested that these agents can cause genetic damage. However, they have not been tested for genotoxicity related to repetitive administration. The aim of this study was to evaluate the genotoxic potential of local anaesthetics upon repetitive administration. METHODS: 80 male Wistar rats were divided into: group A - 16 rats intraperitoneally injected with lidocaine hydrochloride 2%; group B - 16 rats IP injected with mepivacaine 2%; group C - 16 rats intraperitoneally injected with articaine 4%; group D - 16 rats IP injected with prilocaine 3% (6.0 mg/kg; group E - 8 rats subcutaneously injected with a single dose of cyclophosphamide; and group F - 8 rats intraperitoneally injected with saline. Eight rats from groups A to D received a single dose of anaesthetic on Day 1 of the experiment; the remaining rats were dosed once a day for 5 days. RESULTS: The median number of micronuclei in the local anaesthetics groups exposed for 1 or 5 days ranged from 0.00 to 1.00, in the cyclophosphamide-exposed group was 10.00, and the negative control group for 1 and 5 days was 1.00 and 0.00, respectively (p 0.05. CONCLUSION: No genotoxicity effect was observed upon repetitive exposure to any of the local anaesthetics evaluated.

  1. Evaluation of genotoxic effect of silver nanoparticles (Ag-Nps) in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, Priscila; Balbinot, Fernanda; Martins de Oliveira, Hugo; Elibio Fagundes, Gabriela [PPGCS, Universidade do Extremo Sul Catarinense, Laboratorio de Biologia Celular e Molecular (Brazil); Venancio, Mireli; Vieira Ronconi, Joao Vitor; Merlini, Aline [Universidade do Extremo Sul Catarinense, Laboratorio de Sintese de Complexos Multifuncionais (Brazil); Streck, Emilio L. [Programa de Pos-Graduacao em Ciencias da Saude, Unidade Academica de Ciencias da Saude, Universidade do Extremo Sul Catarinense, Laboratorio de Fisiopatologia Experimental (Brazil); Marques da Silva, Paula [Universidade do Extremo Sul Catarinense, Laboratorio de Sintese de Complexos Multifuncionais (Brazil); Moraes de Andrade, Vanessa, E-mail: vmoraesdeandrade@yahoo.com.br [PPGCS, Universidade do Extremo Sul Catarinense, Laboratorio de Biologia Celular e Molecular (Brazil)

    2012-03-15

    Silver nanoparticles (Ag-NPs) are the most prominent nanoproducts. Due to their antimicrobial activity, they have been incorporated in different materials, such as catheters, clothes, electric home appliance, and many others. The genotoxicity of Ag-NPs (5-45 nm), in different concentrations and times of exposure, was evaluated by the comet assay in in vitro and in vivo conditions, respectively, using human peripheral blood and Swiss mice. The results showed the genotoxic effect of Ag-NPs in vitro, in all the doses tested in the initial hour of exposure, possibly through the reactive oxygen species generation. Nevertheless, the values for this damage decrease with time, indicating that the DNA may have been restored by the repair system. In the in vivo conditions, we found no genotoxicity of Ag-NPs in any hour of exposure and any dose investigated, which can be attributed to the activation of a cellular antioxidant network and the hydrophobic nature of Ag-NPs. Now, it is absolutely necessary to investigate the role of Ag-NPs in different cell lines in vivo.

  2. Evaluation of Genotoxic and Cytotoxic Effects in Human Peripheral Blood Lymphocytes Exposed In Vitro to Neonicotinoid Insecticides News

    Directory of Open Access Journals (Sweden)

    María Elena Calderón-Segura

    2012-01-01

    Full Text Available Calypso (thiacloprid, Poncho (clothianidin, Gaucho (imidacloprid, and Jade (imidacloprid are commercial neonicotinoid insecticides, a new class of agrochemicals in México. However, genotoxic and cytotoxic studies have not been performed. In the present study, human peripheral blood lymphocytes (PBL were exposed in vitro to different concentrations of the four insecticides. The genotoxic and cytotoxic effects were evaluated using the alkaline comet and trypan blue dye exclusion assays. DNA damage was evaluated using two genotoxicity parameters: tail length and comet frequency. Exposure to 9.5×10-6 to 5.7×10-5 M Jade; 2.8×10-4 to 1.7×10-3 M Gaucho; 0.6×10-1 to 1.4×10-1 M Calypso; 1.2×10-1 to 9.5×10-1 M Poncho for 2 h induced a significant increase DNA damage with a concentration-dependent relationship. Jade was the most genotoxic of the four insecticides studied. Cytotoxicity was observed in cells exposed to 18×10-3 M Jade, 2.0×10-3 M Gaucho, 2.0×10-1 M Calypso, 1.07 M Poncho, and cell death occurred at 30×10-3 M Jade, 3.3×10-3 M Gaucho, 2.8×10-1 M Calypso, and 1.42 M Poncho. This study provides the first report of genotoxic and cytotoxic effects in PBL following in vitro exposure to commercial neonicotinoid insecticides.

  3. Evaluation of Genotoxic and Cytotoxic Effects in Human Peripheral Blood Lymphocytes Exposed In Vitro to Neonicotinoid Insecticides News

    Science.gov (United States)

    Calderón-Segura, María Elena; Gómez-Arroyo, Sandra; Villalobos-Pietrini, Rafael; Martínez-Valenzuela, Carmen; Carbajal-López, Yolanda; Calderón-Ezquerro, María del Carmen; Cortés-Eslava, Josefina; García-Martínez, Rocío; Flores-Ramírez, Diana; Rodríguez-Romero, María Isabel; Méndez-Pérez, Patricia; Bañuelos-Ruíz, Enrique

    2012-01-01

    Calypso (thiacloprid), Poncho (clothianidin), Gaucho (imidacloprid), and Jade (imidacloprid) are commercial neonicotinoid insecticides, a new class of agrochemicals in México. However, genotoxic and cytotoxic studies have not been performed. In the present study, human peripheral blood lymphocytes (PBL) were exposed in vitro to different concentrations of the four insecticides. The genotoxic and cytotoxic effects were evaluated using the alkaline comet and trypan blue dye exclusion assays. DNA damage was evaluated using two genotoxicity parameters: tail length and comet frequency. Exposure to 9.5 × 10−6 to 5.7 × 10−5 M Jade; 2.8 × 10−4 to 1.7 × 10−3 M Gaucho; 0.6 × 10−1 to 1.4 × 10−1 M Calypso; 1.2 × 10−1 to 9.5 × 10−1 M Poncho for 2 h induced a significant increase DNA damage with a concentration-dependent relationship. Jade was the most genotoxic of the four insecticides studied. Cytotoxicity was observed in cells exposed to 18 × 10−3 M Jade, 2.0 × 10−3 M Gaucho, 2.0 × 10−1 M Calypso, 1.07 M Poncho, and cell death occurred at 30 × 10−3 M Jade, 3.3 × 10−3 M Gaucho, 2.8 × 10−1 M Calypso, and 1.42 M Poncho. This study provides the first report of genotoxic and cytotoxic effects in PBL following in vitro exposure to commercial neonicotinoid insecticides. PMID:22545045

  4. Hexavalent chromium is cytotoxic and genotoxic to hawksbill sea turtle cells.

    Science.gov (United States)

    Wise, Sandra S; Xie, Hong; Fukuda, Tomokazu; Douglas Thompson, W; Wise, John Pierce

    2014-09-01

    Sea turtles are a charismatic and ancient ocean species and can serve as key indicators for ocean ecosystems, including coral reefs and sea grass beds as well as coastal beaches. Genotoxicity studies in the species are absent, limiting our understanding of the impact of environmental toxicants on sea turtles. Hexavalent chromium (Cr(VI)) is a ubiquitous environmental problem worldwide, and recent studies show it is a global marine pollutant of concern. Thus, we evaluated the cytotoxicity and genotoxicity of soluble and particulate Cr(VI) in hawksbill sea turtle cells. Particulate Cr(VI) was both cytotoxic and genotoxic to sea turtle cells. Concentrations of 0.1, 0.5, 1, and 5μg/cm(2) lead chromate induced 108, 79, 54, and 7% relative survival, respectively. Additionally, concentrations of 0, 0.1, 0.5, 1, and 5μg/cm(2) lead chromate induced damage in 4, 10, 15, 26, and 36% of cells and caused 4, 11, 17, 30, and 56 chromosome aberrations in 100 metaphases, respectively. For soluble Cr, concentrations of 0.25, 0.5, 1, 2.5, and 5μM sodium chromate induced 84, 69, 46, 25, and 3% relative survival, respectively. Sodium chromate induced 3, 9, 9, 14, 21, and 29% of metaphases with damage, and caused 3, 10, 10, 16, 26, and 39 damaged chromosomes in 100 metaphases at concentrations of 0, 0.25, 0.5, 1, 2.5, and 5μM sodium chromate, respectively. These data suggest that Cr(VI) may be a concern for hawksbill sea turtles and sea turtles in general.

  5. Hexavalent chromium is cytotoxic and genotoxic to hawksbill sea turtle cells

    Energy Technology Data Exchange (ETDEWEB)

    Wise, Sandra S., E-mail: sandra.wise@maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Maine Center for Toxicology and Environmental Health, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Xie, Hong, E-mail: hongxie@usm.maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Maine Center for Toxicology and Environmental Health, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Fukuda, Tomokazu, E-mail: tomofukuda009@gmail.com [Graduate School of Agricultural Sciences, Tohoku University, Laboratory of Animal Breeding and Genetics, Second Research Building, Rm 112, 1-1 Amamiyamachi, Aoba-ku, Sendai 981-8555 (Japan); Douglas Thompson, W., E-mail: dougt@usm.maine.edu [Maine Center for Toxicology and Environmental Health, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); Department of Applied Medical Science, University of Southern Maine, Science Building, 96 Falmouth Street, Portland, ME 04103 (United States); and others

    2014-09-01

    Sea turtles are a charismatic and ancient ocean species and can serve as key indicators for ocean ecosystems, including coral reefs and sea grass beds as well as coastal beaches. Genotoxicity studies in the species are absent, limiting our understanding of the impact of environmental toxicants on sea turtles. Hexavalent chromium (Cr(VI)) is a ubiquitous environmental problem worldwide, and recent studies show it is a global marine pollutant of concern. Thus, we evaluated the cytotoxicity and genotoxicity of soluble and particulate Cr(VI) in hawksbill sea turtle cells. Particulate Cr(VI) was both cytotoxic and genotoxic to sea turtle cells. Concentrations of 0.1, 0.5, 1, and 5 μg/cm{sup 2} lead chromate induced 108, 79, 54, and 7% relative survival, respectively. Additionally, concentrations of 0, 0.1, 0.5, 1, and 5 μg/cm{sup 2} lead chromate induced damage in 4, 10, 15, 26, and 36% of cells and caused 4, 11, 17, 30, and 56 chromosome aberrations in 100 metaphases, respectively. For soluble Cr, concentrations of 0.25, 0.5, 1, 2.5, and 5 μM sodium chromate induced 84, 69, 46, 25, and 3% relative survival, respectively. Sodium chromate induced 3, 9, 9, 14, 21, and 29% of metaphases with damage, and caused 3, 10, 10, 16, 26, and 39 damaged chromosomes in 100 metaphases at concentrations of 0, 0.25, 0.5, 1, 2.5, and 5 μM sodium chromate, respectively. These data suggest that Cr(VI) may be a concern for hawksbill sea turtles and sea turtles in general. - Highlights: • Particulate Cr(VI) is cytotoxic and clastogenic to hawksbill sea turtle cells. • Soluble Cr(VI) is cytotoxic and clastogenic to hawksbill sea turtle cells. • Cr(VI) may be a risk factor for hawksbill sea turtle health.

  6. Genotoxic evaluation of infusions of Urera baccifera leaves and roots in Allium cepa cells

    Directory of Open Access Journals (Sweden)

    Amanda L. Gindri

    2015-04-01

    Full Text Available Context: The aqueous extracts of Urera baccifera Wedd. leaves and roots are used to inflammatory and infectious diseases in Brazilian folk medicine. Oxalic acid, a substance co-related with toxicity and stinging, was already quantified in this plant. Aims: To evaluate the action of leaves and roots infusions (1, 30, 75 g/L and the oxalic acid standard on mitosis as indicative of presumably antimitotic and genotoxic actions, using the Allium cepa test. Methods: Oxalic acid was quantified in the roots and leaves infusions by High-performance liquid chromatography (HPLC-DAD, with the mobile phase of 25 mM phosphate buffer (pH 2.5: acetonitrile at 95:5 (v/v. To the genotoxicity test, onion bulbs were used. After the rootlets germination, each bulb was submitted for 24 h of the individual treatments. Were analyzed 1000 cells per bulb, in a total of 5000 cells per treatment. Results: Results showed that all concentrations of roots infusions induced chromosomes abnormalities, except for the highest, that caused a substantial inhibition in the mitosis, precluding to be observed abnormalities. In the leaves infusions, only the two higher concentrations caused the highest values of damage in the cellular cycle. The oxalic acid also caused abnormalities in the mitosis, and may be considered responsible by part of the genotoxic action of U. baccifera. Conclusions: Oxalic acid can be responsible by part of the chromosomal abnormalities caused by U. baccifera, although, there must have more metabolites that evoke the same effect promoting the genotoxic effect of this nettle.

  7. Aroclor 1254 increases the genotoxicity of several carcinogens to liver primary cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza-Figueroa, T.; Lopez-Revilla, R.; Villa-Trevino, S.

    1985-01-01

    The genotoxicity of both direct-acting and precarcinogenic chemicals was evaluated in liver primary cell cultures (LPCC) from untreated and Aroclor 1254 (Ar) pretreated rats. Hepatocytes were isolated from partially hepatectomized rats and their DNA was labeled in vitro with (/sup 3/H) dThd; the molecular weight of single-stranded DNA was determined by alkaline sucrose sedimentation. Two parameters of DNA damage were defined: 1) the mean effective dose (ED50), i.e., the carcinogen concentration that decreased the DNA molecular weight to half the original, and 2) the DNA breaking potency (DBP), i.e., the number of breaks per DNA molecule produced by 2 h exposure to 1mM concentration of the chemical. Two hours exposure of LPCC from untreated rats to the direct-acting alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) (6.8-340..mu..M) and to the precarcinogens benzo(a)pyrene (BaP) (0.05-0.33 mM) and dimethylnitrosamine (DMN) (0.45-16 mM) produced a concentration-dependent decrease in the molecular weight of DNA. Pretreatment of rats with Ar decreased significantly the sedimentation velocity of DNA and increased five, three, and two times the DBP of MNNG, BaP, and DMN, respectively. These results show that Ar-pretreatment of rats increases the genotoxicity of both direct-acting and precarcinogenic chemicals and suggest that Ar might increase the genotoxicity of chemical carcinogens perhaps by enhancing their metabolic activation, by producing direct genotoxic effects, or both. Our results also emphasize the carcinogenic risk that the environmental pollution by polychlorinated biphenyls might represent to humans.

  8. Aroclor 1254 increases the genotoxicity of several carcinogens to liver primary cell cultures.

    Science.gov (United States)

    Mendoza-Figueroa, T; López-Revilla, R; Villa-Treviño, S

    1985-01-01

    The genotoxicity of both direct-acting and precarcinogenic chemicals was evaluated in liver primary cell cultures (LPCC) from untreated and Aroclor 1254 (Ar) pretreated rats. Hepatocytes were isolated from partially hepatectomized rats and their DNA was labeled in vitro with [3H] dThd; the molecular weight of single-stranded DNA was determined by alkaline sucrose sedimentation. Two parameters of DNA damage were defined: the mean effective dose (ED50), i.e., the carcinogen concentration that decreased the DNA molecular weight to half the original, and the DNA breaking potency (DBP), i.e., the number of breaks per DNA molecule produced by 2 h exposure to 1 mM concentration of the chemical. Two hours exposure of LPCC from untreated rats to the direct-acting alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) (6.8-340 microM) and to the precarcinogens benzo[a]pyrene (BaP) (0.05-0.33 mM) and dimethylnitrosamine (DMN) (0.45-16 mM) produced a concentration-dependent decrease in the molecular weight of DNA. Pretreatment of rats with Ar decreased significantly the sedimentation velocity of DNA and increased five, three, and two times the DBP of MNNG, BaP, and DMN, respectively. These results show that Ar-pretreatment of rats increases the genotoxicity of both direct-acting and precarcinogenic chemicals and suggest that Ar might increase the genotoxicity of chemical carcinogens perhaps by enhancing their metabolic activation, by producing direct genotoxic effects, or both. Our results also emphasize the carcinogenic risk that the environmental pollution by polychlorinated biphenyls might represent to humans.

  9. Genotoxic and mutagenic effects of lipid-coated CdSe/ZnS quantum dots.

    Science.gov (United States)

    Aye, Mélanie; Di Giorgio, Carole; Berque-Bestel, Isabelle; Aime, Ahissan; Pichon, Benoit P; Jammes, Yves; Barthélémy, Philippe; De Méo, Michel

    2013-01-20

    We proposed to evaluate the genotoxicity and mutagenicity of a new quantum dots (QDs) nanoplatform (QDsN), consisting of CdSe/ZnS core-shell QDs encapsulated by a natural fusogenic lipid (1,2-di-oleoyl-sn-glycero-3-phosphocholine (DOPC)) and functionalized by a nucleolipid N-[5'-(2',3'-di-oleoyl) uridine]-N',N',N'-trimethylammoniumtosylate (DOTAU). This QDs nanoplatform may represent a new therapeutic tool for the diagnosis and treatment of human cancers. The genotoxic, mutagenic and clastogenic effects of QDsN were compared to those of cadmium chloride (CdCl(2)). Three assays were used: (1) the Salmonella/microsome assay with four tester strains, (2) the comet assay and (3) the micronucleus test on CHO cells. The contribution of simulated sunlight was studied in the three assays while oxidative events were only explored in the comet assay in aliquots pretreated with the antioxidant l-ergothioneine. We found that QDsN could enter CHO-K1 cells and accumulate in cytoplasmic vesicles. It was not mutagenic in the Salmonella/mutagenicity test whereas CdCl(2) was weakly positive. In the dark, both the QDsN and CdCl(2) similarly induced dose-dependent increases in single-strand breaks and micronuclei. Exposure to simulated sunlight significantly potentiated the genotoxic activities of both QDsN and CdCl(2), but did not significantly increase micronucleus frequencies. l-Ergothioneine significantly reduced but did not completely suppress the DNA-damaging activity of QDsN and CdCl(2). The present results clearly point to the genotoxic properties and the risk of long-term adverse effects of such a nanoplatform if used for human anticancer therapy and diagnosis in the future.

  10. Qualitative and quantitative approaches in the dose-response assessment of genotoxic carcinogens.

    Science.gov (United States)

    Fukushima, Shoji; Gi, Min; Kakehashi, Anna; Wanibuchi, Hideki; Matsumoto, Michiharu

    2016-05-01

    Qualitative and quantitative approaches are important issues in field of carcinogenic risk assessment of the genotoxic carcinogens. Herein, we provide quantitative data on low-dose hepatocarcinogenicity studies for three genotoxic hepatocarcinogens: 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and N-nitrosodiethylamine (DEN). Hepatocarcinogenicity was examined by quantitative analysis of glutathione S-transferase placental form (GST-P) positive foci, which are the preneoplastic lesions in rat hepatocarcinogenesis and the endpoint carcinogenic marker in the rat liver medium-term carcinogenicity bioassay. We also examined DNA damage and gene mutations which occurred through the initiation stage of carcinogenesis. For the establishment of points of departure (PoD) from which the cancer-related risk can be estimated, we analyzed the above events by quantitative no-observed-effect level and benchmark dose approaches. MeIQx at low doses induced formation of DNA-MeIQx adducts; somewhat higher doses caused elevation of 8-hydroxy-2'-deoxyquanosine levels; at still higher doses gene mutations occurred; and the highest dose induced formation of GST-P positive foci. These data indicate that early genotoxic events in the pathway to carcinogenesis showed the expected trend of lower PoDs for earlier events in the carcinogenic process. Similarly, only the highest dose of IQ caused an increase in the number of GST-P positive foci in the liver, while IQ-DNA adduct formation was observed with low doses. Moreover, treatment with DEN at low doses had no effect on development of GST-P positive foci in the liver. These data on PoDs for the markers contribute to understand whether genotoxic carcinogens have a threshold for their carcinogenicity. The most appropriate approach to use in low dose-response assessment must be approved on the basis of scientific judgment.

  11. Multigenerational demographic responses of sexual and asexual Artemia to chronic genotoxicity by a reference mutagen.

    Science.gov (United States)

    Sukumaran, Sandhya; Grant, Alastair

    2013-11-15

    Genotoxins are capable of multigenerational impacts on natural populations via DNA damage and mutations. Sexual reproduction is assumed to reduce the long term consequences of genotoxicity for individual fitness and should therefore reduce population level effects. However, rather few empirical studies have quantified the magnitude of this effect. We tried to analyse the multigenerational demographic responses of sexual Artemia franciscana and asexual Artemia parthenogenetica due to chronic genotoxicity by a reference mutagen, ethyl methane sulfonate (EMS). A prospective (elasticity analysis) and retrospective (differences and contributions) perturbation analysis was carried out to understand the interactions of life history traits with population growth rate λ by comparing elasticities, differences and contributions of vital rates to λ. None of the previous studies have compared the effects of chronic genotoxicity using prospective and retrospective perturbation analyses in a sexual and asexual species over generations. The behaviour of a population with lower growth rate in the presence of genotoxicants in the field was studied by simulating reduced fertilities in the LTRE design. The results of prospective and retrospective perturbation analyses of effects on λ showed that population growth rate was proportionally more sensitive to juvenile survival whereas the effect of EMS on juvenile fertility contributed more to the variations in population growth rate in both the species and this effect was due to the high growth rate of Artemia. Simulations of lower population growth rate in the model showed that adult fertility and survival are also of importance. Sexual reproduction substantially mitigated the long term consequences of genetic damage, although these would be greater if population growth rate were lower. So multigenerational population level consequences of genotoxicity were much greater in an asexual species. So asexual species, and those with a

  12. Genotoxicity Induced by Foetal and Infant Exposure to Magnetic Fields and Modulation of Ionising Radiation Effects.

    Directory of Open Access Journals (Sweden)

    Ion Udroiu

    Full Text Available Few studies have investigated the toxicity and genotoxicity of extremely low frequency magnetic fields (ELF-MF during prenatal and neonatal development. These phases of life are characterized by cell proliferation and differentiation, which might make them sensitive to environmental stressors. Although in vitro evidences suggest that ELF-MF may modify the effects of ionizing radiation, no research has been conducted so far in vivo on the genotoxic effects of ELF-MF combined with X-rays.Aim of this study was to investigate in somatic and germ cells the effects of chronic ELF-MF exposure from mid gestation until weaning, and any possible modulation produced by ELF-MF exposure on ionizing radiation-induced damage. Mice were exposed to 50 Hz, 65 μT magnetic field, 24 hours/day, for a total of 30 days, starting from 12 days post-conception. Another group was irradiated with 1 Gy X-rays immediately before ELF-MF exposure, other groups were only X-irradiated or sham-exposed. Micronucleus test on blood erythrocytes was performed at multiple times from 1 to 140 days after birth. Additionally, 42 days after birth, genotoxic and cytotoxic effects on male germ cells were assessed by comet assay and flow cytometric analysis.ELF-MF exposure had no teratogenic effect and did not affect survival, growth and development. The micronucleus test indicated that ELF-MF induced a slight genotoxic damage only after the maximum exposure time and that this effect faded away in the months following the end of exposure. ELF-MF had no effects on ionizing radiation (IR-induced genotoxicity in erythrocytes. Differently, ELF-MF appeared to modulate the response of male germ cells to X-rays with an impact on proliferation/differentiation processes. These results point to the importance of tissue specificity and development on the impact of ELF-MF on the early stages of life and indicate the need of further research on the molecular mechanisms underlying ELF-MF biological

  13. Chromatin structure and DNA damage repair

    Directory of Open Access Journals (Sweden)

    Dinant Christoffel

    2008-11-01

    Full Text Available Abstract The integrity of the genome is continuously challenged by both endogenous and exogenous DNA damaging agents. These damaging agents can induce a wide variety of lesions in the DNA, such as double strand breaks, single strand breaks, oxidative lesions and pyrimidine dimers. The cell has evolved intricate DNA damage response mechanisms to counteract the genotoxic effects of these lesions. The two main features of the DNA damage response mechanisms are cell-cycle checkpoint activation and, at the heart of the response, DNA repair. For both damage signalling and repair, chromatin remodelling is most likely a prerequisite. Here, we discuss current knowledge on chromatin remodelling with respect to the cellular response to DNA damage, with emphasis on the response to lesions resolved by nucleotide excision repair. We will discuss the role of histone modifications as well as their displacement or exchange in nucleotide excision repair and make a comparison with their requirement in transcription and double strand break repair.

  14. Evaluation of genotoxicity of combined soil pollution by cadmium and phenanthrene on earthworm

    Institute of Scientific and Technical Information of China (English)

    ZHU Jiang; ZHAO Zuo-yuan; LU Yi-tong

    2006-01-01

    The DNA-damaging effects of the combined pollution of heavy metal and organic contamination on earthworms were evaluated by single cell gel electrophoresis (SCGE) assay. Earthworms Eisenia andrei were exposed to single or combined test compounds in different doses of cadmium (Cd) 5, 10, 50 mg/kg and phenanthrene (Phe) 0.5, 2.5, 12.5 mg/kg with a treatment of 14 d.In SCGE assay, isolated coelomcytes and electrophoresis were employed to determine DNA damage degree after a 14-d treatment by test compounds. The results showed that there was a significant statistical difference between earthworms treated with Cd combined Phe with them treated alone with Cd or Phe. The Olive tail moment (OTM) of SCGE assay using earthworm coelomcytes appears to be a sensitive biomarker for evaluating exposure to genotoxic compounds. These tests also revealed that the interaction between Cd and Phe to DNA damaging effects was negative, and was strongly dependent on the concentration of pollution. This study corresponds to exploratory phase in order to reveal interaction effects of heavy metal and organic contamination on earthworms and then to set up more in-depth analysis to increase progressively the understanding of the genotoxicity mechanisms involved.

  15. Evaluation of genotoxic and antigenotoxic properties of essential oils of Seseli rigidum Waldst. & Kit. (Apiaceae

    Directory of Open Access Journals (Sweden)

    Živković Lada

    2016-01-01

    Full Text Available The essential oils of genus Seseli are known for their beneficial biological activities and could present novel targets in the development of safe and effective preparations of plant products. The objective was to test the essential oils of different parts of Seseli rigidum from two natural habitats for potential genotoxic and antigenotoxic activities against H202-induced DNA damage in human whole blood cells in vitro, by the comet assay. The essential oil analysis showed a high falcarinol content in oil from the root, while oils of the fruit and aerial parts contained α-pinene as the main compound. Genotoxicity was not detected at any of the concentrations of the essential oils from the three parts of the plant from localities I and II. Although the antioxidant activity (established by the FRAP and DPPH tests of the investigated oils was low, all oils demonstrated a strong antigenotoxic effect against H2O2-induced damage post-treatment, when the oils were applied after the oxidant. Based on the lack of pretreatment activity and the post-treatment reduction in DNA damage, the antigenotoxic effect of S. rigidum essential oils was probably based on the stimulation of DNA repair mechanisms. Environmental conditions did not affect the antigenotoxic properties of the oils. In conclusion, our results revealed the antigenotoxic properties of S. rigidum essential oils and appropriate and safe doses with beneficial effects under the described conditions. [Projekat Ministarstva nauke Republike Srbije, br. OI 173034, 173021

  16. Genotoxicity assessment of cobalt chloride in Eisenia hortensis earthworms coelomocytes by comet assay and micronucleus test.

    Science.gov (United States)

    Ciğerci, İbrahim Hakkı; Ali, Muhammad Muddassir; Kaygısız, Şöhret Yüksek; Liman, Recep

    2016-02-01

    Cobalt and its different compounds are extensively used worldwide and considered as possible environmental pollutant. Earthworms are useful model organism and its different species are used to monitor soil pollution. No study has been found to detect cobalt chloride (CoCl2) genotoxicity in earthworms. So, current study aimed to evaluate CoCl2 induced genotoxicity in Eisenia hortensis earthworms coelomocytes by alkaline comet assay (CA) and micronucleus (MN) test. The earthworms (n = 10 for each group) were exposed to different series of CoCl2 concentrations (100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm) to find LD50. The LD50 for CoCl2 was found at 226 ppm. Then, doses of LD50/2, LD50 and 2XLD50 for 48 h were used. CA and MN demonstrated the significant increase (P < 0.05) in DNA damage and chromosomal aberrations. Dose dependent relationship was found. Highest DNA damage and chromosomal aberrations were noticed at 2XLD50. The results concluded that CoCl2 induced DNA damage, cytokinesis failure and chromosomal aberrations in E. hortensis earthworms.

  17. Micronuclei as biomarkers of genotoxicity of gamma radiation in aquatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luanna R.S.; Silva, Edvane B.; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Silva, Ronaldo C. da [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Genetica; Amancio, Francisco F. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia

    2011-07-01

    Ionizing radiation is a genotoxic agent, inducing gene mutations and cellular death. Several efforts have been defendants in the development of techniques for measurement of radiation damage in biological systems. Among these techniques, micronuclei test has been showing as a great bio marker of DNA damage, being used in environmental monitoring to detect genotoxic agents in the environment. Additionally, organisms as Biomphalaria glabrata, freshwater molluscs, presents itself as an excellent model to assess damage caused by physical and chemical agents, due their biological and environmental characteristics. The snails were divided into groups of 5 individuals exposed to doses of 0 (control), 25, 35, 45 and 55 Gy of {sup 60}Co. After 48 hours of irradiation, the hemo lymph was collected and prepared the slides, which were stained with Giemsa and analyzed the cellular changes in haemocytes Statistical analysis was accomplished through chi-square test, ANOVA and Tukey test (p< 0,05). The results indicated that B. glabrata showed to be sensitive to gamma radiation. The snails irradiated with 35 Gy showed a decrease of haemocytes, while that of 55 Gy increased. Cellular and morphological changes were observed at doses of 35, 45 and 55 Gy and the dose of 55 Gy, the most radiotoxic. (author)

  18. Comet assay to assess the genotoxicity of Persian walnut (Juglans regia L.) husks with statistical evaluation.

    Science.gov (United States)

    Petriccione, Milena; Ciniglia, Claudia

    2012-07-01

    The aim of this study was to confirm the utility of the Comet assay as a genotoxicity screening test for evaluating the impact of walnut husk aqueous extract. Phytotoxicity assays using diluted and undiluted walnut husk aqueous extracts were performed on young roots of Raphanus sativus (radish), and the Comet assay was used to evaluate DNA integrity in isolated radish radicle nuclei. The results reveal a dose-dependent accumulation of DNA damage in radish radicles treated with walnut husks water extract and that the Kolmogorov-Smirnov test combined with Johnson SB distribution was the best approach for describing Comet assay data.

  19. Genotoxic monitoring of workers at a hazardous waste disposal site in Mexico.

    Science.gov (United States)

    Gonsebatt, M E; Salazar, A M; Montero, R; Díaz Barriga, F; Yáñez, L; Gómez, H; Ostrosky-Wegman, P

    1995-01-01

    Chromosomal aberration and sister chromatid exchange (SCE) frequencies were determined in lymphocytes cultured from 12 high-risk individuals working at a landfill for hazardous waste disposal. Cell proliferation kinetics (CPK) was also determined. Compared with 7 control individuals, no effects were observed with respect to SCE nor on CPK. However, the workers exhibited significantly higher frequencies of chromatid and chromosomal deletions, the magnitude of which was related with exposure time. This study suggests that when high-risk exposure is suspected, determining biomarkers of genotoxic damage (e.g., chromosomal aberrations), is useful for risk assessments. PMID:7621789

  20. Cytotoxic, genotoxic/antigenotoxic and mutagenic/antimutagenic effects of the venom of the wasp Polybia paulista.

    Science.gov (United States)

    Hoshina, Márcia M; Santos, Lucilene D; Palma, Mario S; Marin-Morales, Maria A

    2013-09-01

    Hymenoptera venoms are constituted by a complex mixture of chemically or pharmacologically bioactive agents, such as phospholipases, hyaluronidases and mastoparans. Venoms can also contain substances that are able to inhibit and/or diminish the genotoxic or mutagenic action of other compounds that are capable of promoting damages in the genetic material. Thus, the present study aimed to assess the effect of the venom of Polybia paulista, a neotropical wasp, by assays with HepG2 cells maintained in culture. The cytotoxic potential of the wasp venom, assessed by the methyl thiazolyl tetrazolium assay (MTT assay), was tested for the concentrations of 10 μg/mL, 5 μg/mL and 1 μg/mL. As these concentrations were not cytotoxic, they were used to evaluate the genotoxic (comet assay) and mutagenic potential (micronucleus test) of the venom. In this study, it was verified that these concentrations induced damages in the DNA of the exposed cells, and it was necessary to test lower concentrations until it was found those that were not considered genotoxic and mutagenic. The concentrations of 1 ng/mL, 100 pg/mL and 10 pg/mL, which did not induce genotoxicity and mutagenicity, were used in four different treatments (post-treatment, pre-treatment, simultaneous treatment with and without incubation), in order to evaluate if these concentrations were able to inhibit or decrease the genotoxic and mutagenic action of methyl methanesulfonate (MMS). None of the concentrations was able to inhibit and/or decrease the MMS activity. The genotoxic and mutagenic activity of the venom of P. paulista could be caused by the action of phospholipase, mastoparan and hyaluronidase, which are able to disrupt the cell membrane and thereby interact with the genetic material of the cells or even facilitate the entrance of other compounds of the venom that can act on the DNA. Another possible explanation for the genotoxicity and mutagenicity of the venom can be the presence of substances able

  1. Comparative DNA Damage and Repair in Echinoderm Coelomocytes Exposed to Genotoxicants

    OpenAIRE

    El-Bibany, Ameena H.; Bodnar, Andrea G.; Reinardy, Helena C.

    2014-01-01

    The capacity to withstand and repair DNA damage differs among species and plays a role in determining an organism's resistance to genotoxicity, life history, and susceptibility to disease. Environmental stressors that affect organisms at the genetic level are of particular concern in ecotoxicology due to the potential for chronic effects and trans-generational impacts on populations. Echinoderms are valuable organisms to study the relationship between DNA repair and resistance to genotoxic st...

  2. Temporally distinct roles of ATM and ROS in genotoxic-stress-dependent induction and maintenance of cellular senescence.

    Science.gov (United States)

    Nair, Raji R; Bagheri, Meisam; Saini, Deepak Kumar

    2015-01-15

    Cells exposed to genotoxic stress induce cellular senescence through a DNA damage response (DDR) pathway regulated by ATM kinase and reactive oxygen species (ROS). Here, we show that the regulatory roles for ATM kinase and ROS differ during induction and maintenance of cellular senescence. Cells treated with different genotoxic agents were analyzed using specific pathway markers and inhibitors to determine that ATM kinase activation is directly proportional to the dose of the genotoxic stress and that senescence initiation is not dependent on ROS or the p53 status of cells. Cells in which ROS was quenched still activated ATM and initiated the DDR when insulted, and progressed normally to senescence. By contrast, maintenance of a viable senescent state required the presence of ROS as well as activated ATM. Inhibition or removal of either of the components caused cell death in senescent cells, through a deregulated ATM-ROS axis. Overall, our work demonstrates existence of an intricate temporal hierarchy between genotoxic stress, DDR and ROS in cellular senescence. Our model reports the existence of different stages of cellular senescence with distinct regulatory networks.

  3. The efficiency of combined CaO/electrochemical treatment in removal of acid mine drainage induced toxicity and genotoxicity.

    Science.gov (United States)

    Radić, Sandra; Vujčić, Valerija; Cvetković, Želimira; Cvjetko, Petra; Oreščanin, Višnja

    2014-01-01

    Acid mine drainage (AMD) is a by-product of the mining industry that has a detrimental effect on aquatic plant and animal life due to high load of heavy metals and sulfates. In the present study, the toxic and genotoxic potential of AMD prior to and following combination of neutralization/electrocoagulation processes was evaluated using several bioassays and selected parameters. Regardless of pH correction of AMD prior to Daphnia bioassay, high acute toxicity was observed in Daphnia magna. The mine leachate also induced strong phyto-, cyto- and genotoxicity to Allium cepa roots. Short term exposure to AMD inhibited duckweed growth and chlorophyll a content and simultaneously promoted lipid peroxidation and DNA damage despite duckweed capability to upregulate antioxidative defense mechanisms. The results show that observed (geno)toxicity could be related to oxidative stress most probably induced by toxic metal action. However, influence of low pH as a contributing factor in the phytotoxicity of AMD cannot be excluded. The application of combined treatment eliminated genotoxicity and was highly efficient in reducing toxicity of AMD. Thus, the method seems to be suitable for treatment of AMD waters enabling their safe discharge to an aquatic environment.

  4. Acute and chronic effects of erythromycin exposure on oxidative stress and genotoxicity parameters of Oncorhynchus mykiss

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, S., E-mail: up201208875@fc.up.pt [Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169–007 Porto (Portugal); Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Antunes, S.C. [Departamento de Biologia da Faculdade de Ciências da Universidade do Porto (FCUP), Rua do Campo Alegre s/n, 4169–007 Porto (Portugal); Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Correia, A.T. [Centro Interdisciplinar de Investigação Marinha e Ambiental (CIIMAR/CIMAR), Rua dos Bragas 289, 4050–123 Porto (Portugal); Faculdade de Ciências da Saúde da Universidade Fernando Pessoa (FCS-UFP), Rua Carlos da Maia, 296, 4200–150, Porto (Portugal); Nunes, B. [Centro de Estudos do Ambiente e do Mar (CESAM), Campus de Santiago, Universidade de Aveiro, 3810–193 Aveiro (Portugal); Departamento de Biologia, Universidade de Aveiro, Campus de Santiago, 3810–193 Aveiro (Portugal)

    2016-03-01

    Erythromycin (ERY) is a macrolide antibiotic used in human and veterinary medicine, and has been detected in various aquatic compartments. Recent studies have indicated that this compound can exert biological activity on non-target organisms environmentally exposed. The present study aimed to assess the toxic effects of ERY in Oncorhynchus mykiss after acute and chronic exposures. The here adopted strategy involved exposure to three levels of ERY, the first being similar to concentrations reported to occur in the wild, thus ecologically relevant. Catalase (CAT), total glutathione peroxidase (GPx), glutathione reductase (GRed) activities and lipid peroxidation (TBARS levels) were quantified as oxidative stress biomarkers in gills and liver. Genotoxic endpoints, reflecting different types of genetic damage in blood cells, were also determined, by performing analysis of genetic damage (determination of the genetic damage index, GDI, measured by comet assay) and of erythrocytic nuclear abnormalities (ENAs). The results suggest the occurrence of a mild, but significant, oxidative stress scenario in gills. For acutely exposed organisms, significant alterations were observed in CAT and GRed activities, and also in TBARS levels, which however are modifications with uncertain biological interpretation, despite indicating involvement of an oxidative effect and response. After chronic exposure, a significant decrease of CAT activity, increase of GPx activity and TBARS levels in gills was noticed. In liver, significant decrease in TBARS levels were observed in both exposures. Comet and ENAs assays indicated significant increases on genotoxic damage of O. mykiss, after erythromycin exposures. This set of data (acute and chronic) suggests that erythromycin has the potential to induce DNA strand breaks in blood cells, and demonstrate the induction of chromosome breakage and/or segregational abnormalities. Overall results indicate that both DNA damaging effects induced by

  5. Oxidatively damaged DNA in animals exposed to particles

    DEFF Research Database (Denmark)

    Møller, Peter; Danielsen, Pernille Høgh; Jantzen, Kim

    2013-01-01

    Exposure to combustion-derived particles, quartz and asbestos is associated with increased levels of oxidized and mutagenic DNA lesions. The aim of this survey was to critically assess the measurements of oxidatively damaged DNA as marker of particle-induced genotoxicity in animal tissues...

  6. Evaluation of genotoxicity of the acute gamma radiation on earthworm Eisenia fetida using single cell gel electrophoresis technique (Comet assay).

    Science.gov (United States)

    Sowmithra, K; Shetty, N J; Jha, S K; Chaubey, R C

    2015-12-01

    Earthworms (Eisenia fetida) most suitable biological indicators of radioactive pollution. Radiation-induced lesions in DNA can be considered to be molecular markers for early effects of ionizing radiation. Gamma radiation produces a wide spectrum of DNA. Some of these lesions, i.e., DNA strand breaks and alkali labile sites can be detected by the single-cell gel electrophoresis (SCGE) or comet assay by measuring the migration of DNA from immobilized nuclear DNA. E. fetida were exposed to different doses of gamma radiation, i.e., 1, 5, 10, 20, 30, 40 and 50Gy, and comet assay was performed for all the doses along with control at 1, 3 and 5h post irradiation to evaluate the genotoxicity of gamma radiation in this organism. The DNA damage was measured as percentage of comet tail DNA. A significant increase in DNA damage was observed in samples exposed to 5Gy and above, and the increase in DNA damage was dose dependent i.e., DNA damage was increased with increased doses of radiation. The highest DNA damage was noticed at 1h post irradiation and gradually decreased with time, i.e., at 3 and 5h post irradiation. The present study reveals that gamma radiation induces DNA damage in E. fetida and the comet assay is a sensitive and rapid method for its detection to detect genotoxicity of gamma radiation.

  7. Genotoxicity evaluation of alpha-linolenic acid-diacylglycerol oil

    Directory of Open Access Journals (Sweden)

    Hiroshi Honda

    2016-01-01

    Full Text Available The alpha-linolenic acid (ALA-diacylglycerol (DAG oil is an edible oil enriched with DAG (>80% and ALA (>50%. Although DAG oil, which mainly consists of oleic and linoleic acids has no genotoxic concerns, the fatty acid composition could affect the chemical property of DAG. Therefore, the purpose of this study was to evaluate the genotoxicity of ALA-DAG oil using standard genotoxicity tests in accordance with the OECD guidelines. ALA-DAG oil showed negative results in the bacterial reverse mutation test (Ames test and in vitro micronucleus test in cultured Chinese hamster lung cells with and without metabolic activation, and in the in vivo bone marrow micronucleus test in mice. Our results did not show any genotoxicity, suggesting that the fatty acid composition had no deleterious effects. We conclude that ALA-DAG oil had no genotoxicity concerns under the testing conditions.

  8. Genotoxicity of Anesthetics Evaluated In Vivo (Animals)

    Science.gov (United States)

    Braz, Mariana G.; Karahalil, Bensu

    2015-01-01

    The anesthesia has been improved all over the years. However, it can have impact on health, in both patients and animals anesthetized, as well as professionals exposed to inhaled anesthetics. There is continuing effort to understand the possible effects of anesthetics at molecular levels. Knowing the effects of anesthetic agents on genetic material could be a valuable basic support to better understand the possible mechanisms of these agents. Thus, the purpose of this review is to provide an overview on the genotoxic potential, evaluated in animal models, of many anesthetics that have already been used and those currently used in anesthesia. PMID:26199936

  9. Genotoxicity assessment of 4-methylimidazole: regulatory perspectives

    OpenAIRE

    Morita, Takeshi; Uneyama, Chikako

    2016-01-01

    4-Methylimidazole (4-MI) is formed as a result of the Maillard reaction process, and therefore is found in many foods and beverages. It is also found in soft drinks (i.e., cola) as a by-product in the production of some caramel colors. NTP bioassays revealed clear evidence of lung carcinogenicity of 4-MI in male and female mice, but not in rats and then IARC classified 4-MI as group 2B carcinogen. Genotoxicity studies with 4-MI were negative in the Ames tests and in the erythrocyte micronucle...

  10. Genotoxicity Expert Panel review: weight of evidence evaluation of the genotoxicity of glyphosate, glyphosate-based formulations, and aminomethylphosphonic acid.

    Science.gov (United States)

    Brusick, David; Aardema, Marilyn; Kier, Larry; Kirkland, David; Williams, Gary

    2016-09-01

    In 2015, the International Agency for Research on Cancer (IARC) published a monograph concluding there was strong evidence for genotoxicity of glyphosate and glyphosate formulations and moderate evidence for genotoxicity of the metabolite aminomethylphosphonic acid (AMPA). These conclusions contradicted earlier extensive reviews supporting the lack of genotoxicity of glyphosate and glyphosate formulations. The IARC Monograph concluded there was strong evidence of induction of oxidative stress by glyphosate, glyphosate formulations, and AMPA. The Expert Panel reviewed the genotoxicity and oxidative stress data considered in the IARC Monograph, together with other available data not considered by IARC. The Expert Panel defined and used a weight of evidence (WoE) approach that included ranking of studies and endpoints by the strength of their linkage to events associated with carcinogenic mechanisms. Importantly, the Expert Panel concluded that there was sufficient information available from a very large number of regulatory genotoxicity studies that should have been considered by IARC. The WoE approach, the inclusion of all relevant regulatory studies, and some differences in interpretation of individual studies led to significantly different conclusions by the Expert Panel compared with the IARC Monograph. The Expert Panel concluded that glyphosate, glyphosate formulations, and AMPA do not pose a genotoxic hazard and the data do not support the IARC Monograph genotoxicity evaluation. With respect to carcinogenicity classification and mechanism, the Expert Panel concluded that evidence relating to an oxidative stress mechanism of carcinogenicity was largely unconvincing and that the data profiles were not consistent with the characteristics of genotoxic carcinogens.

  11. The Chromatin Scaffold Protein SAFB1 Renders Chromatin Permissive for DNA Damage Signaling

    DEFF Research Database (Denmark)

    Altmeyer, Matthias; Toledo Lazaro, Luis Ignacio; Gudjonsson, Thorkell

    2013-01-01

    the chromatin-associated scaffold attachment factor SAFB1 as a component of the DNA damage response and show that SAFB1 cooperates with histone acetylation to allow for efficient γH2AX spreading and genotoxic stress signaling. SAFB1 undergoes a highly dynamic exchange at damaged chromatin in a poly...

  12. Carbon black nanoparticle instillation induces sustained inflammation and genotoxicity in mouse lung and liver

    DEFF Research Database (Denmark)

    Bourdon, Julie A; Saber, Anne T; Jacobsen, Nicklas R;

    2012-01-01

    Widespread occupational exposure to carbon black nanoparticles (CBNPs) raises concerns over their safety. CBNPs are genotoxic in vitro but less is known about their genotoxicity in various organs in vivo.......Widespread occupational exposure to carbon black nanoparticles (CBNPs) raises concerns over their safety. CBNPs are genotoxic in vitro but less is known about their genotoxicity in various organs in vivo....

  13. Cytotoxicity and Genotoxicity of Ceria Nanoparticles on Different Cell Lines in Vitro

    Directory of Open Access Journals (Sweden)

    Sandro Santucci

    2013-02-01

    Full Text Available Owing to their radical scavenging and UV-filtering properties, ceria nanoparticles (CeO2-NPs are currently used for various applications, including as catalysts in diesel particulate filters. Because of their ability to filter UV light, CeO2-NPs have garnered significant interest in the medical field and, consequently, are poised for use in various applications. The aim of this work was to investigate the effects of short-term (24 h and long-term (10 days CeO2-NP exposure to A549, CaCo2 and HepG2 cell lines. Cytotoxicity assays tested CeO2-NPs over a concentration range of 0.5 μg/mL to 5000 μg/mL, whereas genotoxicity assays tested CeO2-NPs over a concentration range of 0.5 μg/mL to 5000 μg/mL. In vitro assays showed almost no short-term exposure toxicity on any of the tested cell lines. Conversely, long-term CeO2-NP exposure proved toxic for all tested cell lines. NP genotoxicity was detectable even at 24-h exposure. HepG2 was the most sensitive cell line overall; however, the A549 line was most sensitive to the lowest concentration tested. Moreover, the results confirmed the ceria nanoparticles’ capacity to protect cells when they are exposed to well-known oxidants such as H2O2. A Comet assay was performed in the presence of both H2O2 and CeO2-NPs. When hydrogen peroxide was maintained at 25 μM, NPs at 0.5 μg/mL, 50 μg/mL, and 500 μg/mL protected the cells from oxidative damage. Thus, the NPs prevented H2O2-induced genotoxic damage.

  14. Genotoxicity of nano/microparticles in in vitro micronuclei, in vivo comet and mutation assay systems

    Directory of Open Access Journals (Sweden)

    Fukumori Nobutaka

    2009-09-01

    Full Text Available Abstract Background Recently, manufactured nano/microparticles such as fullerenes (C60, carbon black (CB and ceramic fiber are being widely used because of their desirable properties in industrial, medical and cosmetic fields. However, there are few data on these particles in mammalian mutagenesis and carcinogenesis. To examine genotoxic effects by C60, CB and kaolin, an in vitro micronuclei (MN test was conducted with human lung cancer cell line, A549 cells. In addition, DNA damage and mutations were analyzed by in vivo assay systems using male C57BL/6J or gpt delta transgenic mice which were intratracheally instilled with single or multiple doses of 0.2 mg per animal of particles. Results In in vitro genotoxic analysis, increased MN frequencies were observed in A549 cells treated with C60, CB and kaolin in a dose-dependent manner. These three nano/microparticles also induced DNA damage in the lungs of C57BL/6J mice measured by comet assay. Moreover, single or multiple instillations of C60 and kaolin, increased either or both of gpt and Spi- mutant frequencies in the lungs of gpt delta transgenic mice. Mutation spectra analysis showed transversions were predominant, and more than 60% of the base substitutions occurred at G:C base pairs in the gpt genes. The G:C to C:G transversion was commonly increased by these particle instillations. Conclusion Manufactured nano/microparticles, CB, C60 and kaolin, were shown to be genotoxic in in vitro and in vivo assay systems.

  15. Mechanistic evaluation of Ginkgo biloba leaf extract-induced genotoxicity in L5178Y cells.

    Science.gov (United States)

    Lin, Haixia; Guo, Xiaoqing; Zhang, Suhui; Dial, Stacey L; Guo, Lei; Manjanatha, Mugimane G; Moore, Martha M; Mei, Nan

    2014-06-01

    Ginkgo biloba has been used for many thousand years as a traditional herbal remedy and its extract has been consumed for many decades as a dietary supplement. Ginkgo biloba leaf extract is a complex mixture with many constituents, including flavonol glycosides and terpene lactones. The National Toxicology Program 2-year cancer bioassay found that G. biloba leaf extract targets the liver, thyroid gland, and nose of rodents; however, the mechanism of G. biloba leaf extract-associated carcinogenicity remains unclear. In the current study, the in vitro genotoxicity of G. biloba leaf extract and its eight constituents was evaluated using the mouse lymphoma assay (MLA) and Comet assay. The underlying mechanisms of G. biloba leaf extract-associated genotoxicity were explored. Ginkgo biloba leaf extract, quercetin, and kaempferol resulted in a dose-dependent increase in the mutant frequency and DNA double-strand breaks (DSBs). Western blot analysis confirmed that G. biloba leaf extract, quercetin, and kaempferol activated the DNA damage signaling pathway with increased expression of γ-H2AX and phosphorylated Chk2 and Chk1. In addition, G. biloba leaf extract produced reactive oxygen species and decreased glutathione levels in L5178Y cells. Loss of heterozygosity analysis of mutants indicated that G. biloba leaf extract, quercetin, and kaempferol treatments resulted in extensive chromosomal damage. These results indicate that G. biloba leaf extract and its two constituents, quercetin and kaempferol, are mutagenic to the mouse L5178Y cells and induce DSBs. Quercetin and kaempferol likely are major contributors to G. biloba leaf extract-induced genotoxicity.

  16. Genotoxic effect of N-hydroxy-4-acetylaminobiphenyl on human DNA: implications in bladder cancer.

    Directory of Open Access Journals (Sweden)

    Uzma Shahab

    Full Text Available BACKGROUND: The interaction of environmental chemicals and their metabolites with biological macromolecules can result in cytotoxic and genotoxic effects. 4-Aminobiphenyl (4-ABP and several other related arylamines have been shown to be causally involved in the induction of human urinary bladder cancers. The genotoxic and the carcinogenic effects of 4-ABP are exhibited only when it is metabolically converted to a reactive electrophile, the aryl nitrenium ions, which subsequently binds to DNA and induce lesions. Although several studies have reported the formation of 4-ABP-DNA adducts, no extensive work has been done to investigate the immunogenicity of 4-ABP-modified DNA and its possible involvement in the generation of antibodies in bladder cancer patients. METHODOLOGY/PRINCIPAL FINDINGS: Human DNA was modified by N-hydroxy-4-acetylaminobiphenyl (N-OH-AABP, a reactive metabolite of 4-ABP. Structural perturbations in the N-OH-AABP modified DNA were assessed by ultraviolet, fluorescence, and circular dichroic spectroscopy as well as by agarose gel electrophoresis. Genotoxicity of N-OH-AABP modified DNA was ascertained by comet assay. High performance liquid chromatography (HPLC analysis of native and modified DNA samples confirmed the formation of N-(deoxyguanosine-8-yl-4-aminobiphenyl (dG-C8-4ABP in the N-OH-AABP damaged DNA. The experimentally induced antibodies against N-OH-AABP-modified DNA exhibited much better recognition of the DNA isolated from bladder cancer patients as compared to the DNA obtained from healthy individuals in competitive binding ELISA. CONCLUSIONS/SIGNIFICANCE: This work shows epitope sharing between the DNA isolated from bladder cancer patients and the N-OH-AABP-modified DNA implicating the role of 4-ABP metabolites in the DNA damage and neo-antigenic epitope generation that could lead to the induction of antibodies in bladder cancer patients.

  17. Toxicity and genotoxicity in Astyanax bimaculatus (Characidae induced by microcystins from a bloom of Microcystis spp

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    Ricardo Rocha Pavan da Silva

    2010-01-01

    Full Text Available Studies of genotoxicity in fish caused by cyanobacterial microcystins can be useful both in determining the sensitivity of native species, as well as comparing exposure routes. The genotoxicity caused by the microcystins LR and LA from a bloom collected in a eutrophic lake, was revealed in the fish Astyanax bimaculatus, a native species from South America. LC50 (72 h was determined as 242.81 µg L-1 and LD50 (72 h as 49.19 µg kg-1 bw. There was a significant increase of DNA damage in peripheral erythrocytes, following intraperitoneal injection (ip with tested concentrations of 24.58 µg kg-1 bw and 36.88 µg kg-1 bw, as well as through body exposure to a concentration of 103.72 µg L-1. Micronucleus (MN induction was observed after ip injections of 24.58 µg kg-1 bw and 36.88 µg kg-1 bw for 72 h, as well as following body exposure for 72 at 103.72 µg L-1. Thus, both exposure routes resulted in MN induction and DNA damage. Apoptosis-necrosis testing was carried out only by ip injection with concentrations of 24.58 µg -1 bw and 36.88 µg kg-1 bw. Exposure to microcystins at lower concentrations induced more apoptosis than necrosis in peripheral erythrocytes, whereas exposure at higher concentrations gave rise to both conditions. Thus, Astyanax bimaculatus can be considered as a species sensitive to the genotoxic effects caused by microcystins.

  18. Beryllium metal I. experimental results on acute oral toxicity, local skin and eye effects, and genotoxicity.

    Science.gov (United States)

    Strupp, Christian

    2011-01-01

    The toxicity of soluble metal compounds is often different from that of the parent metal. Since no reliable data on acute toxicity, local effects, and mutagenicity of beryllium metal have ever been generated, beryllium metal powder was tested according to the respective Organisation for Economical Co-Operation and Development (OECD) guidelines. Acute oral toxicity of beryllium metal was investigated in rats and local effects on skin and eye in rabbits. Skin-sensitizing properties were investigated in guinea pigs (maximization method). Basic knowledge about systemic bioavailability is important for the design of genotoxicity tests on poorly soluble substances. Therefore, it was necessary to experimentally compare the capacities of beryllium chloride and beryllium metal to form ions under simulated human lung conditions. Solubility of beryllium metal in artificial lung fluid was low, while solubility in artificial lysosomal fluid was moderate. Beryllium chloride dissolution kinetics were largely different, and thus, metal extracts were used in the in vitro genotoxicity tests. Genotoxicity was investigated in vitro in a bacterial reverse mutagenicity assay, a mammalian cell gene mutation assay, a mammalian cell chromosome aberration assay, and an unscheduled DNA synthesis (UDS) assay. In addition, cell transformation was tested in a Syrian hamster embryo cell assay, and potential inhibition of DNA repair was tested by modification of the UDS assay. Beryllium metal was found not to be mutagenic or clastogenic based on the experimental in vitro results. Furthermore, treatment with beryllium metal extracts did not induce DNA repair synthesis, indicative of no DNA-damaging potential of beryllium metal. A cell-transforming potential and a tendency to inhibit DNA repair when the cell is severely damaged by an external stimulus were observed. Beryllium metal was also found not to be a skin or eye irritant, not to be a skin sensitizer, and not to have relevant acute oral

  19. International Conference on Harmonisation; guidance on S2(R1) Genotoxicity Testing and Data Interpretation for Pharmaceuticals intended for Human Use; availability. Notice.

    Science.gov (United States)

    2012-06-07

    The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled ``S2(R1) Genotoxicity Testing and Data Interpretation for Pharmaceuticals Intended for Human Use'' (ICH S2(R1)). This guidance was prepared under the auspices of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The ICH S2(R1) combines and replaces two ICH guidances, "S2A Specific Aspects for Regulatory Genotoxicity Tests for Pharmaceuticals'' and "S2B Genotoxicity: A Standard Battery for Genotoxicity Testing of Pharmaceuticals.'' ICH S2(R1) provides guidance to drug sponsors on which tests should be performed to assess potential genotoxicity of pharmaceuticals. It also provides guidance on testing conditions, data interpretation, and followup strategies if a positive response is seen in in vitro assays. This guidance is intended to provide drug sponsors with recommendations to ensure that drugs are appropriately tested for potential to cause genetic damage and to ensure efficient development of new drugs.

  20. Neoplastic transformation of breast epithelial cells by genotoxic stress

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    Raman Venu

    2010-06-01

    Full Text Available Abstract Background Exposure to genotoxic stresses such as radiation and tobacco smoke can cause increased cancer incidence rate as reflected in an in depth meta-analysis of data for women and breast cancer incidence. Published reports have indicated that exposures to low dose radiation and tobacco smoke are factors that contribute to the development of breast cancer. However, there is a scarcity of information on the combinatorial effects of low dose radiation and tobacco smoke on formation and progression of breast cancer. The combination of these two genotoxic insults can induce significant damage to the genetic material of the cells resulting in neoplastic transformation. Methods To study the effects of low dose ionizing radiation and tobacco smoke on breast cells, MCF 10A cells were treated either with radiation (Rad - 0.1 Gray or cigarette smoke condensate (Csc - 10 microgram/ml of medium or a combination of Rad + Csc. Following treatments, cells were analyzed for cell cycle distribution patterns and the ability to extrude the Hoechst 33342 dye. In addition, in vitro invasion and migration as well as mammosphere formation assays were performed. Finally, differential gene expression profiles were generated from the individual and combination treatment. Results Exposure of MCF 10A cells to the combination of radiation plus cigarette smoke condensate generated a neoplastic phenotype. The transformed phenotype promoted increased mammosphere numbers, altered cell cycle phases with a doubling of the population in S phase, and increased invasion and motility. Also, exclusion of Hoechst 33342 dye, a surrogate marker for increased ABC transporters, was observed, which indicates a possible increase in drug resistance. In addition, changes in gene expression include the up regulation of genes encoding proteins involved in metabolic pathways and inflammation. Conclusions The results indicate that when normal breast cells are exposed to low dose

  1. Forskolin: genotoxicity assessment in Allium cepa.

    Science.gov (United States)

    Mohammed, Khalid Pasha; Aarey, Archana; Tamkeen, Shayesta; Jahan, Parveen

    2015-01-01

    Forskolin, a diterpene, 7β-acetoxy-8,13-epoxy-1α,6β,9α-trihydroxy-labd-14-en-11-one (C22H34O7) isolated from Coleus forskohlii, exerts multiple physiological effects by stimulating the enzyme adenylate cyclase and increasing cyclic adenosine monophosphate (cAMP) concentrations. Forskolin is used in the treatment of hypertension, congestive heart failure, eczema, and other diseases. A cytogenetic assay was performed in Allium cepa to assess possible genotoxic effects of forskolin. Forskolin was tested at concentrations 5-100 μM for exposure periods of 24 or 48 h. Treated samples showed significant reductions in mitotic index (p < 0.05) and increases in the frequency of chromosome aberrations (p < 0.01) at both exposure times. The treated meristems showed chromosome aberrations including sticky metaphases, sticky anaphases, laggard, anaphase bridges, micronuclei, polyploidy, fragments, breaks, and C-mitosis. Forskolin may cause genotoxic effects and further toxicological evaluations should be conducted to ensure its safety.

  2. Steviol glycoside safety: is the genotoxicity database sufficient?

    Science.gov (United States)

    Urban, J D; Carakostas, M C; Brusick, D J

    2013-01-01

    The safety of steviol glycoside sweeteners has been extensively reviewed in the literature. National and international food safety agencies and approximately 20 expert panels have concluded that steviol glycosides, including the widely used sweeteners stevioside and rebaudioside A, are not genotoxic. However, concern has been expressed in recent publications that steviol glycosides may be mutagenic based on select studies representing a small fraction of the overall database, and it has been suggested that further in vivo genotoxicity studies are required to complete their safety profiles. To address the utility of conducting additional in vivo genotoxicity studies, this review evaluates the specific genotoxicity studies that are the sources of concern, and evaluates the adequacy of the database including more recent genotoxicity data not mentioned in those publications. The current database of in vitro and in vivo studies for steviol glycosides is robust and does not indicate that either stevioside or rebaudioside A are genotoxic. This, combined with a lack of evidence for neoplasm development in rat bioassays, establish the safety of all steviol glycosides with respect to their genotoxic/carcinogenic potential.

  3. In-vitro carbofuran induced genotoxicity in human lymphocytes and its mitigation by vitamins C and E.

    Science.gov (United States)

    Sharma, Ratnesh Kumar; Sharma, Bechan

    2012-01-01

    Various efforts have been made in past in order to predict the underlying mechanism of pesticide-induced toxicity using in vitro and animal models, however, these predictions may or may not be directly correlated with humans. The present study was designed to investigate the carbofuran induced genotoxicity and its amelioration by vitamins C and E by treating human peripheral blood lymphocytes (PBLs) with different concentrations (0, 0.5, 1.25, 2.5, 3.75 and 5.0 μM) of this compound. The treatment of PBLs with carbofuran displayed significant DNA damage in concentration dependent manner. The carbofuran induced genotoxicity could be ameliorated to considerable extent by pretreatment of PBLs with equimolar (10 μM) concentration of each of the vitamins C and E; the magnitude of protection by vitamin E being higher than by vitamin C. Also, it was found that the level of protection by these vitamins was higher when PBLs were treated with lower concentrations of pesticide. The significant DNA damage as observed by H_{2}O_{2}, a positive control in the present study, and its amelioration by natural antioxidants (vitamins C and E) lend an evidence to suggest that carbofuran would have caused genotoxicity via pesticide induced oxidative stress.

  4. Evaluation of genotoxicity and DNA protective effects of mangiferin, a glucosylxanthone isolated from Mangifera indica L. stem bark extract.

    Science.gov (United States)

    Rodeiro, I; Hernandez, S; Morffi, J; Herrera, J A; Gómez-Lechón, M J; Delgado, R; Espinosa-Aguirre, J J

    2012-09-01

    Mangiferin is a glucosylxantone isolated from Mangifera indica L. stem bark. Several studies have shown its pharmacological properties which make it a promising candidate for putative therapeutic use. This study was focused to investigate the in vitro genotoxic effects of mangiferin in the Ames test, SOS Chromotest and Comet assay. The genotoxic effects in bone marrow erythrocytes from NMRI mice orally treated with mangiferin (2000 mg/kg) were also evaluated. Additionally, its potential antimutagenic activity against several mutagens in the Ames test and its effects on CYP1A1 activity were assessed. Mangiferin (50-5000 μg/plate) did not increased the frequency of reverse mutations in the Ames test, nor induced primary DNA damage (5-1000 μg/mL) to Escherichia coli PQ37 cells under the SOS Chromotest. It was observed neither single strand breaks nor alkali-labile sites in blood peripheral lymphocytes or hepatocytes after 1h exposition to 10-500 μg/mL of mangiferin under the Comet assay. Furthermore, micronucleus studies showed mangiferin neither induced cytotoxic activity nor increased the frequency of micronucleated/binucleated cells in mice bone marrow. In short, mangiferin did not induce cytotoxic or genotoxic effects but it protect against DNA damage which would be associated with its antioxidant properties and its capacity to inhibit CYP enzymes.

  5. In-Vitro Carbofuran Induced Genotoxicity in Human Lymphocytes and Its Mitigation by Vitamins C and E

    Directory of Open Access Journals (Sweden)

    Ratnesh Kumar Sharma

    2012-01-01

    Full Text Available Various efforts have been made in past in order to predict the underlying mechanism of pesticide-induced toxicity using in vitro and animal models, however, these predictions may or may not be directly correlated with humans. The present study was designed to investigate the carbofuran induced genotoxicity and its amelioration by vitamins C and E by treating human peripheral blood lymphocytes (PBLs with different concentrations (0, 0.5, 1.25, 2.5, 3.75 and 5.0 μM of this compound. The treatment of PBLs with carbofuran displayed significant DNA damage in concentration dependent manner. The carbofuran induced genotoxicity could be ameliorated to considerable extent by pretreatment of PBLs with equimolar (10 μM concentration of each of the vitamins C and E; the magnitude of protection by vitamin E being higher than by vitamin C. Also, it was found that the level of protection by these vitamins was higher when PBLs were treated with lower concentrations of pesticide. The significant DNA damage as observed by H2O2, a positive control in the present study, and its amelioration by natural antioxidants (vitamins C and E lend an evidence to suggest that carbofuran would have caused genotoxicity via pesticide induced oxidative stress.

  6. Genotoxic effects of Tabebuia impetiginosa (Mart. Ex DC. Standl. (Lamiales, Bignoniaceae extract in Wistar rats

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    Odilon A. Lemos

    2012-01-01

    Full Text Available Tabebuia sp. is native to tropical rain forests throughout Central and South America. Although the biological and pharmacological effects of bark extracts have been intensely studied, little is known on the extract obtained from the flower. Herein, the genotoxic potential of a flower extract from T. impetiginosa ("ipê roxo" on the blood and liver cells of Wistar rats was evaluated. Experimental procedures involved only male animals. Graduated concentrations of the extract, viz., 100, 300 and 500 mg kg-1 of body weight, were gavage-administered and 24 h latter cells were collected and processed for analysis. With the exception of the 100 mg kg-1 dose, a significant increase in DNA damage was noted, when compared with a negative control group. Although the genotoxic potential of this extract was higher in liver cells, the response in both tissues was related to dose-dependency. Even though DNA damage can be corrected before conversion into mutations, further study is recommended to arrive at a better understanding of incurred biological effects.

  7. Genotoxic effects of Tabebuia impetiginosa (Mart. Ex DC.) Standl. (Lamiales, Bignoniaceae) extract in Wistar rats.

    Science.gov (United States)

    Lemos, Odilon A; Sanches, Júlio C M; Silva, Icaro E F; Silva, Márcio L A; Vinhólis, Adriana H C; Felix, Mireille A P; Santos, Raquel A; Cecchi, Andréa O

    2012-04-01

    Tabebuia sp. is native to tropical rain forests throughout Central and South America. Although the biological and pharmacological effects of bark extracts have been intensely studied, little is known on the extract obtained from the flower. Herein, the genotoxic potential of a flower extract from T. impetiginosa ("ipê roxo") on the blood and liver cells of Wistar rats was evaluated. Experimental procedures involved only male animals. Graduated concentrations of the extract, viz., 100, 300 and 500 mg kg(-1) of body weight, were gavage-administered and 24 h latter cells were collected and processed for analysis. With the exception of the 100 mg kg(-1) dose, a significant increase in DNA damage was noted, when compared with a negative control group. Although the genotoxic potential of this extract was higher in liver cells, the response in both tissues was related to dose-dependency. Even though DNA damage can be corrected before conversion into mutations, further study is recommended to arrive at a better understanding of incurred biological effects.

  8. Determination of genotoxicity of classical swine fever vaccine in vitro by cytogenetic and comet tests.

    Science.gov (United States)

    Genghini, R; Tiranti, I; Bressán, E; Zamorano-Ponce, E; Fernández, J; Dulout, F

    2006-05-01

    Chromosome damage in lymphocyte cultures induced by live virus vaccine against classical swine fever (CSF) has been observed in previous studies. In vivo cytogenetic tests were made with several doses of vaccines used in Argentina to control the disease. These studies have shown that genotoxic effects increased with dose. In the present study, two different in vitro assays were performed by recording the frequency of cells with chromosome alterations and by assessing the ability of the vaccine to damage DNA, using the single cell gel microelectrophoretic assay (comet test). Frequencies of cells with chromosomal alterations increased significantly when compared with controls and were dose (microl/ml) dependent: 0 = 1.23, 5 = 2.29, 10 = 5.42 and 20 = 11.71%. In the comet assay the variables measured, tail length (TL) and tail moment (TM), also increased. For control cultures TL was 2.32 microm, whereas with concentrations of 20 and 100 microl/ml TL were 12.47 and 42.3 microm, respectively. TM of control cultures was 0.18, whereas with vaccine concentrations of 20 and 100 microl/ml TM were 5.52 and 24.52, respectively. Comet frequency distributions differed significantly among treatments. These results agree with previous in vivo observations. Regarding CSF pathogeny, our results support a direct effect of CSF vaccinal virus on lymphocyte DNA. Genotoxicity of CSF vaccine was corroborated in vitro at the cytogenetic and molecular levels.

  9. Evaluation of cold shock-induced cytotoxicity and genotoxicity in the house fly Musca domestica

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    Nidhi Mishra

    2014-05-01

    Full Text Available Background: Low temperature affects the survival, growth and development of invertebrates, especially insects, based on the severity of cold and the duration of exposure. Although the effects of cold shock or direct chilling were previously analysed in terms of development patterns and defects, morphological changes, cold hardiness, cryopreservation and diapause in insects, very little information is available regarding the effects of cold shock at the chromosomal level. Material and Methods: Late third instar larvae of the house fly Musca domestica were exposed to low temperatures (10, 4, 0 and -5°C for different durations, in order to assess genotoxicity and cytotoxicity in the present study. The chromosomal aberration assay and micronucleus test were used as genotoxic end points. Cytotoxicity was evaluated by the mitotic index and the extent of tissue damage was observed using the Trypan blue staining method. Results: A significant (P<0.05, P<0.01 and P<0.001 increase in chromosome aberrations and micronucleus frequency was observed in all of the exposed groups compared to the control. The mitotic index showed a dose-dependent increase; however, it was lower in comparison to the control. The developmental patterns in exposed larvae exhibited an increase in larval mortality and a delay in adult emergence. Extensive tissue damage was observed at -5°C by Trypan blue staining. Conclusions: The present work suggests that cold shock induces chromosome aberrations and cytotoxicity and affects the developmental pattern in house fly, M. domestica.

  10. Protective effects of acerola juice on genotoxicity induced by iron in vivo

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    Roberta Nunes Horta

    2016-03-01

    Full Text Available Abstract Metal ions such as iron can induce DNA damage by inducing reactive oxygen species (ROS and oxidative stress. Vitamin C is one of the most widely consumed antioxidants worldwide, present in many fruits and vegetables, especially inMalpighia glabra L., popularly known as acerola, native to Brazil. Acerola is considered a functional fruit due to its high antioxidant properties and phenolic contents, and therefore is consumed to prevent diseases or as adjuvant in treatment strategies. Here, the influence of ripe and unripe acerola juices on iron genotoxicity was analyzed in vivo using the comet assay and micronucleus test. The comet assay results showed that acerola juice exerted no genotoxic or antigenotoxic activity. Neither ripe nor unripe acerola juices were mutagenic to animals treated with juices, in micronucleus test. However, when compared to iron group, the pre-treatment with acerola juices exerted antimutagenic activity, decreasing significantly micronucleus mean values in bone marrow. Stage of ripeness did not influence the interaction of acerola compounds with DNA, and both ripe and unripe acerola juices exerted protective effect over DNA damage generated by iron.

  11. Analysis of genotoxicity and the carcinogenic mode of action for ortho-phenylphenol.

    Science.gov (United States)

    Brusick, David

    2005-06-01

    Ortho-phenylphenol (OPP) and its sodium salt (SOPP) are commercial products that have wide human exposure and have been shown in several studies to be rodent carcinogens. Genetic toxicology data were assessed in an attempt to understand the carcinogenic mode of action of OPP and SOPP. More than 130 studies were evaluated to determine if OPP, SOPP, or any of their enzymatic or nonenzymatic breakdown products react directly with DNA to induce mutation, changes in chromosome structure or number, DNA repair, or nonspecific DNA damage including strand breakage or covalent binding. The genotoxicity databases for OPP and SOPP are not only large but heterogeneous, requiring weight-of-evidence methods to arrive at a conclusion regarding their genotoxic properties and potential. Evidence derived from the available studies leads to the conclusion that study results showing OPP/SOPP directly interacting with DNA are equivocal. Clastogenicity was the most consistent type of genetic toxicity produced by OPP/SOPP (and their break-down products) and was consistently associated with other intracellular preneoplastic toxicity produced at super-threshold concentrations. The weight of evidence from the combined database supports the hypothesis that OPP/SOPP-induced DNA damage is a threshold-dependent response associated with target tissue toxicity, most likely induced by their breakdown products phenylhydroquinone and phenylbenzoquinone. It is possible that this threshold-dependent clastogenicity could contribute to the carcinogenic mode of action for OPP or SOPP.

  12. Can systems toxicology identify common biomarkers of non-genotoxic carcinogenesis?

    Science.gov (United States)

    Plant, Nick

    2008-12-30

    For the rapid development of safe, efficacious chemicals it is important that any potential liabilities are identified as early as possible in the discovery/development pipeline. Once identified it is then possible to make rational decisions on whether to progress a chemical and/or series further; one such liability is chemical carcinogenesis, a highly undesirable characteristic in a novel chemical entity. Chemical carcinogens may be roughly divided into two classes, those that elicit their actions through direct damage to DNA (genotoxic carcinogens) and those that cause carcinogenesis through mechanisms that involve direct damage of the DNA by the agent (non-genotoxic carcinogens). Whereas the former group can be identified by in vitro screens to a good degree of accuracy, the latter group are far more problematic due to their diverse modes of action. This review will focus on the latter class of chemical carcinogens, examining how modern '-omic' technologies have begun to identify signatures that may represent sensitive, early markers for these processes. In addition to their use in signature generation the role of -omic level approaches to delineating molecular mechanisms of action will also be discussed.

  13. [Genotoxicity effect of organic pollutants in Meiliang Bay of Taihu Lake on microalga Euglena gracilis].

    Science.gov (United States)

    Gao, Xiang-Yu; Cui, Yi-Bin; Hu, Chang-Wei; Qian, Xin; Kong, Zhi-Ming; Li, Mei

    2009-11-01

    Organic pollutant ingredients and content of water samples from Taihu Lake were analyzed by GC-MS. Results showed that Taihu Lake was already contaminated by the organic pollutant, and 15 kinds of targeted organic pollutants were detected. At lower concentrations (1 time), organic pollutants could not have notable effect on the growth of Euglena gracilis, but could increase the content of photosynthetic pigment. At higher concentrations (5, 10 times), organic pollutants restrained the growth of E. gracilis remarkably, and decreased the content of photosynthetic pigment. Activities of SOD and POD increased with the content of organic pollutants. It is indicated that organic pollution could induce activities of antioxidation enzymes in E. gracilis. TOM and TM for the genotoxicity assay increased and DNA damage was found. In higher concentration groups, DNA damage was serious and had an obvious dose-effect relationship. It is indicated that Meiliang bay water may have potential mutagenicity. Comet assay combined with SOD analysis was of value to genotoxic monitoring of polluted water and was a suitable biomarker for organic pollutants in water.

  14. In vitro genotoxicity of fipronil sister chromatid exchange, cytokinesis block micronucleus test, and comet assay.

    Science.gov (United States)

    Çelik, Ayla; Ekinci, Seda Yaprak; Güler, Gizem; Yildirim, Seda

    2014-03-01

    Fipronil (FP) is a phenylpyrazole pesticide developed by the transnational company Rhône-Poulenc Agro in 1987. Data on the genotoxicity and toxicity of FP are rather inadequate. In this study, we aimed to evaluate the potential genotoxic activity of FP using the single-cell microgel electrophoresis or comet assay, sister chromatid exchanges (SCEs), and micronuclei (MN) in human peripheral blood lymphocytes. In addition, the cytokinesis block proliferation index (CBPI) and proliferation index (PRI) were measured for cytotoxicity. In this study, three different doses of FP were used (0.7, 0.3, 0.1 μg/mL). Mitomycin C (2 μg/mL) and hydrogen peroxide were used as positive controls for SCE MN test systems, and comet assay, respectively. FP induced a statistically significant increase in the MN and SCE frequency and DNA damage in a dose-dependent manner in human peripheral blood lymphocytes (pcomet assay, we showed that all the doses of the FP induced DNA damage in human peripheral blood lymphocytes in vitro (p<0.05).

  15. Hemocytes of zebra mussels (Dreissena polymorpha are relevant cells for the monitoring of environmental genotoxicity by the comet assay.

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    Marc Bonnard

    2015-06-01

    Full Text Available The measure of DNA integrity by the single cell gel electrophoresis (SCGE or comet assay is especially recommended for its sensitivity and its capacity for detecting different types of damages. Therefore, it has been applied in environmental genotoxicity in a variety of organisms. It appears today necessary to define both reference and threshold levels of DNA damage, for their application in in situ biomonitoring. However, little is known about the influence of both biological (sex, reproduction status or external (temperature… confounding factors on the measure of DNA damage by the comet assay. These variables need to be taken into account if the robustness of the assay is to be established (Jha, 2008. In the zebra mussel Dreissena polymorpha (recommended as a sentinel species in the evaluation of freshwater quality the measure of DNA damage by the comet assay is mainly performed on hemocytes, which are circulating cells involved in key physiological functions such as immunity, homeostasis, detoxication…. This communication will present and discuss results from an innovative study about the variability of the baseline level of DNA damage in hemocytes of mussels encaged for one year in the canal de l’Aisne à la Marne (Reims, according to their sex and their reproductive status. The sensitivity and the suitability of hemocytes in the evaluation of environmental genotoxicity will also be discussed, referring to observations during a 6 month-exposure of mussels in mesocosms to environmentally realistic concentrations of carbamazepine.

  16. ATM and ATR:Sensing DNA damage

    Institute of Scientific and Technical Information of China (English)

    Jun Yang; Zheng-Ping Xu; Yun Huang; Hope E. Hamrick; Penelope J. Duerksen-Hughes; Ying-Nian Yu

    2004-01-01

    Cellular response to genotoxic stress is a very complex process, and it usually starts with the "sensing" or "detection" of the DNA damage, followed by a series of events that include signal transduction and activation of transcription factors. The activated transcription factors induce expressions of many genes which are involved in cellular functions such as DNA repair, cell cycle arrest, and cell death. There have been extensive studies from multiple disciplines exploring the mechanisms of cellular genotoxic responses, which have resulted in the identification of many cellular components involved in this process, including the mitogen-activated protein kinases (MAPKs) cascade. Although the initial activation of protein kinase cascade is not fully understood,human protein kinases ATM (ataxia-telangiectasia, mutated) and ATR (ATM and Rad3-related) are emerging as potential sensors of DNA damage. Current progresses in ATM/ATR research and related signaling pathways are discussed in this review, in an effort to facilitate a better understanding of genotoxic stress response.

  17. Investigation of the cytotoxic, genotoxic, and apoptosis-inducing effects of estragole isolated from fennel (Foeniculum vulgare).

    Science.gov (United States)

    Villarini, Milena; Pagiotti, Rita; Dominici, Luca; Fatigoni, Cristina; Vannini, Samuele; Levorato, Sara; Moretti, Massimo

    2014-04-25

    The present study was undertaken to evaluate, in the HepG2 human hepatoma cell line, the in vitro cytotoxic, genotoxic, and apoptotic activities of estragole (1), contained in the essential oil of Foeniculum vulgare (fennel) and suspected to induce hepatic tumors in susceptible strains of mice. Toward this end, an MTT cytotoxicity assay, a trypan blue dye exclusion test, a double-staining (acridine orange and DAPI) fluorescence viability assay, a single-cell microgel-electrophoresis (comet) assay, a mitochondrial membrane potential (Δψm) assay, and a DNA fragmentation analysis were conducted. In terms of potential genotoxic effects, the comet assay indicated that estragole (1) was not able to induce DNA damage nor apoptosis under the experimental conditions used.

  18. The anthropogenic impact on water quality of the river Danube in Serbia: Microbiological analysis and genotoxicity monitoring

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    Kolarević S.

    2011-01-01

    Full Text Available The aim of this work was to examine the impact of urban wastewaters on the water quality of the Danube River in Serbia. Samples of water and sediments for microbiological analysis and genotoxicity monitoring were collected from 6 sites during spring and/or autumn 2010. Sanitary analysis, i.e. enumeration of total and fecal coliforms and intestinal enterococci, indicated moderate to critical fecal contamination, while organic load assessment (oligotroph to heterotroph ratio, index of phosphatase activity revealed the category of moderately polluted water. Mercury-resistant bacteria were detected in all water samples, with high numbers at locations positioned downstream of Belgrade. There was no correlation of the microbiological parameters of the sediment and water samples. Genotoxicity monitoring, performed by the comet assay on hemocytes of mussels Sinanodonta woodiana, indicated a significant increase of DNA damage in mussels collected from the studied sites compared with the control group.

  19. Effect ofBuchanania lanzan Spreng. bark extract on cyclophosphamide induced genotoxicity and oxidative stress in mice

    Institute of Scientific and Technical Information of China (English)

    Ritesh Jain; Sanmati Kumar Jain

    2012-01-01

    Objective:To elucidate the effect of ethanolic extract ofBuchanania lanzan Spreng. (B. lanan) bark against cyclophosphamide induced genotoxicity and oxidative stress in mice.Methods:The prevalence of micronuclei in bone marrow, the extent of lipid peroxidation, reduced glutathione and the status of the antioxidant enzymes, superoxide dismutase and catalase in liver of mice were used as intermediate biomarkers for chemoprotection. Lipid peroxidation and associated compromised antioxidant defenses in cyclophosphamide treated mice were observed in the liver.Results: Pre-treatment withB. lanzan250, 500 and1 000mg/ kg,p.o., daily for7 days significantly reduced the chromosomal damage and lipid peroxidation with concomitant changes in antioxidants and detoxification systems.Conclusions: These results point out the presence of chemopreventive phytoconstituents in the crude extract offering protection against cyclophosphamide induced genotoxicity and oxidative stress in mice.

  20. Anemia and genotoxicity induced by sub-chronic intragastric treatment of rats with titanium dioxide nanoparticles.

    Science.gov (United States)

    Grissa, Intissar; Elghoul, Jaber; Ezzi, Lobna; Chakroun, Sana; Kerkeni, Emna; Hassine, Mohsen; El Mir, Lassaad; Mehdi, Meriem; Ben Cheikh, Hassen; Haouas, Zohra

    2015-12-01

    Titanium dioxide nanoparticles (TiO2 NPs) are widely used for their whiteness and opacity. We investigated the hematological effects and genotoxicity of anatase TiO2 NPs following sub-chronic oral gavage treatment. TiO2-NPs were characterized by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Wistar rats were treated with anatase TiO2 NPs by intragastric administration for 60 days. Hematological analysis showed a significant decrease in RBC and HCT and a significant increase in MCV, PLT, MPV and WBC at higher doses. Furthermore, abnormally shaped red cells, sometimes containing micronuclei, and hyper-segmented neutrophil nuclei were observed with TiO2 NPs treatment. The micronucleus test revealed damage to chromosomes in rat bone marrow at 100 and 200mg/kg bw; the comet assay showed significant DNA damage at the same doses.

  1. Application of the micronucleus test and comet assay in Trachemys callirostris erythrocytes as a model for in situ genotoxic monitoring.

    Science.gov (United States)

    Zapata, Lina M; Bock, Brian C; Orozco, Luz Yaneth; Palacio, Jaime A

    2016-05-01

    Trachemys callirostris is a turtle species endemic to northern South America. In northern Colombia it occurs in the middle and lower Magdalena River drainage and its principal tributaries (lower Cauca and San Jorge rivers) and in other minor drainages such as the lower Sinú River. In recent years, industrial, agricultural, and mining activities have altered natural habitats in Colombia where this species occurs, and many of the pollutants released there are known to induce genetic alterations in wildlife species. The micronucleus test and comet assay are two of the most widely used methods to characterize DNA damage induced by physical and chemical agents in wildlife species, but have not been employed previously for genotoxic evaluations in T. callirostris. The goal of this study was to optimize these genotoxic biomarkers for T. callirostris erythrocytes in order to establish levels of DNA damage in this species and thereby evaluate its potential as a sentinel species for monitoring genotoxic effects in freshwater environments in northern Colombia. Both genotoxic techniques were applied on peripheral blood erythrocytes from 20 captive-reared T. callirostris individuals as a negative control, as well as from samples obtained from 49 individuals collected in Magangué (Magdalena River drainage) and 24 individuals collected in Lorica (Sinú River drainage) in northern Colombia. Negative control individuals exhibited a baseline frequency of micronuclei of 0.78±0.58 and baseline values for comet tail length and tail moment of 3.34±0.24µm and 10.70±5.5, respectively. In contrast, samples from both field sites exhibited significantly greater evidence of genotoxic effects for both tests. The mean MN frequencies in the samples from Magangué and Lorica were 8.04±7.08 and 12.19±12.94, respectively. The mean tail length for samples from Magangué and Lorica were 5.78±3.18 and 15.46±7.39, respectively. Finally, the mean tail moment for samples from Magangué and

  2. Evaluation of the genotoxicity of cellulose nanofibers

    Directory of Open Access Journals (Sweden)

    de Lima R

    2012-07-01

    plant cells, the most genotoxic nanofibers were those derived from green, white, and brown cotton, and curaua, while genotoxicity in animal cells was observed using nanofibers from brown cotton and curaua. An important finding was that ruby cotton nanofibers did not cause any significant DNA breaks in the cell types employed.Conclusion: This work demonstrates the feasibility of determining the genotoxic potential of nanofibers derived from plant cellulose to obtain information vital both for the future usage of these materials in agribusiness and for an understanding of their environmental impacts.Keywords: cotton, curaua, nanotoxicology, environmental nanotechnology

  3. The genotoxic effects of DNA lesions induced by artificial UV-radiation and sunlight.

    Science.gov (United States)

    Schuch, André Passaglia; Menck, Carlos Frederico Martins

    2010-06-01

    Solar radiation sustains and affects all life forms on Earth. The increase in solar UV-radiation at environmental levels, due to depletion of the stratospheric ozone layer, highlights serious issues of social concern. This becomes still more dramatic in tropical and subtropical regions where radiation-intensity is still higher. Thus, there is the need to evaluate the harmful effects of solar UV-radiation on the DNA molecule as a basis for assessing the risks involved for human health, biological productivity and ecosystems. In order to evaluate the profile of DNA damage induced by this form of radiation and its genotoxic effects, plasmid DNA samples were exposed to artificial-UV lamps and directly to sunlight. The induction of cyclobutane pyrimidine dimer photoproducts (CPDs) and oxidative DNA damage in these molecules were evaluated by means of specific DNA repair enzymes. On the other hand, the biological effects of such lesions were determined through the analysis of the DNA inactivation rate and mutation frequency, after replication of the damaged pCMUT vector in an Escherichia coliMBL50 strain. The results indicated the induction of a significant number of CPDs after exposure to increasing doses of UVC, UVB, UVA radiation and sunlight. Interestingly, these photoproducts are those lesions that better correlate with plasmid inactivation as well as mutagenesis, and the oxidative DNA damages induced present very low correlation with these effects. The results indicated that DNA photoproducts play the main role in the induction of genotoxic effects by artificial UV-radiation sources and sunlight.

  4. Specific uptake and genotoxicity induced by polystyrene nanobeads with distinct surface chemistry on human lung epithelial cells and macrophages.

    Science.gov (United States)

    Paget, Vincent; Dekali, Samir; Kortulewski, Thierry; Grall, Romain; Gamez, Christelle; Blazy, Kelly; Aguerre-Chariol, Olivier; Chevillard, Sylvie; Braun, Anne; Rat, Patrice; Lacroix, Ghislaine

    2015-01-01

    Nanoparticle surface chemistry is known to play a crucial role in interactions with cells and their related cytotoxic effects. As inhalation is a major route of exposure to nanoparticles, we studied specific uptake and damages of well-characterized fluorescent 50 nm polystyrene (PS) nanobeads harboring different functionalized surfaces (non-functionalized, carboxylated and aminated) on pulmonary epithelial cells and macrophages (Calu-3 and THP-1 cell lines respectively). Cytotoxicity of in mass dye-labeled functionalized PS nanobeads was assessed by xCELLigence system and alamarBlue viability assay. Nanobeads-cells interactions were studied by video-microscopy, flow cytometry and also confocal microscopy. Finally ROS generation was assessed by glutathione depletion dosages and genotoxicity was assessed by γ-H2Ax foci detection, which is considered as the most sensitive technique for studying DNA double strand breaks. The uptake kinetic was different for each cell line. All nanobeads were partly adsorbed and internalized, then released by Calu-3 cells, while THP-1 macrophages quickly incorporated all nanobeads which were located in the cytoplasm rather than in the nuclei. In parallel, the genotoxicity study reported that only aminated nanobeads significantly increased DNA damages in association with a strong depletion of reduced glutathione in both cell lines. We showed that for similar nanoparticle concentrations and sizes, aminated polystyrene nanobeads were more cytotoxic and genotoxic than unmodified and carboxylated ones on both cell lines. Interestingly, aminated polystyrene nanobeads induced similar cytotoxic and genotoxic effects on Calu-3 epithelial cells and THP-1 macrophages, for all levels of intracellular nanoparticles tested. Our results strongly support the primordial role of nanoparticles surface chemistry on cellular uptake and related biological effects. Moreover our data clearly show that nanoparticle internalization and observed adverse effects

  5. Specific Uptake and Genotoxicity Induced by Polystyrene Nanobeads with Distinct Surface Chemistry on Human Lung Epithelial Cells and Macrophages

    Science.gov (United States)

    Kortulewski, Thierry; Grall, Romain; Gamez, Christelle; Blazy, Kelly; Aguerre-Chariol, Olivier; Chevillard, Sylvie; Braun, Anne; Rat, Patrice; Lacroix, Ghislaine

    2015-01-01

    Nanoparticle surface chemistry is known to play a crucial role in interactions with cells and their related cytotoxic effects. As inhalation is a major route of exposure to nanoparticles, we studied specific uptake and damages of well-characterized fluorescent 50 nm polystyrene (PS) nanobeads harboring different functionalized surfaces (non-functionalized, carboxylated and aminated) on pulmonary epithelial cells and macrophages (Calu-3 and THP-1 cell lines respectively). Cytotoxicity of in mass dye-labeled functionalized PS nanobeads was assessed by xCELLigence system and alamarBlue viability assay. Nanobeads-cells interactions were studied by video-microscopy, flow cytometry and also confocal microscopy. Finally ROS generation was assessed by glutathione depletion dosages and genotoxicity was assessed by γ-H2Ax foci detection, which is considered as the most sensitive technique for studying DNA double strand breaks. The uptake kinetic was different for each cell line. All nanobeads were partly adsorbed and internalized, then released by Calu-3 cells, while THP-1 macrophages quickly incorporated all nanobeads which were located in the cytoplasm rather than in the nuclei. In parallel, the genotoxicity study reported that only aminated nanobeads significantly increased DNA damages in association with a strong depletion of reduced glutathione in both cell lines. We showed that for similar nanoparticle concentrations and sizes, aminated polystyrene nanobeads were more cytotoxic and genotoxic than unmodified and carboxylated ones on both cell lines. Interestingly, aminated polystyrene nanobeads induced similar cytotoxic and genotoxic effects on Calu-3 epithelial cells and THP-1 macrophages, for all levels of intracellular nanoparticles tested. Our results strongly support the primordial role of nanoparticles surface chemistry on cellular uptake and related biological effects. Moreover our data clearly show that nanoparticle internalization and observed adverse effects

  6. Genotoxicity Testing on the International Space Station: Preparatory Work on the Experiment TRIPLE-LUX

    Science.gov (United States)

    Stojicic, N.; Walrafen, D.; Rabbow, E.; Baumstark-Khan, C.; Rettberg, P.; Weisshaar, M. P.; Horneck, G.

    Harmful environmental factors - namely ionizing radiation - will continue to influence future manned space missions. The Radiation Biology Unit at the German Aerospace Center (DLR) develops cellular monitoring systems, which include bacterial and mammalian cell systems capable of recognizing DNA damage as a consequence of the presence of genotoxic conditions. Such a bioassay is the SWITCH test, which is part of the German space experiment ``Gene, immune and cellular responses to single and combined space flight conditions'' (TRIPLE-LUX) which has been selected by NASA to be performed on the International Space Station. It will supply basic information on the genotoxic response to radiation applied in microgravity. The biological end-point under investigation will depend on the bacterial SOS response brought about by genetically modified bacteria that are transformed with the pSWITCH plasmid (constructed from the plasmids pPLS-1 and pGFPuv). This luminescent/fluorescent bioassay for rapid toxicity (genotoxicity and cytotoxicity) testing, the SWITCH test (SWITCH: {S}almonella {W}eighting of {I}nduced {T}oxicity {C}yto/GenoTox for Human {H}ealth), makes use of two sensing and reporting systems for the two biological endpoints under investigation: the SOS-Lux test and the LAC-Fluoro test. The SWICH plasmid carries the promoterless lux operon of Photobacterium leiognathi as reporter element under the control of the DNA-damage dependent SOS promoter of ColD as sensor element (for genotoxicity testing) and the sequences for a hybrid protein consisting of ß-galactosidase and GFPuv of Aequorea victoria as reporter element under the control of the (in Salmonella constitutively active) LAC promoter of Escherichia coli as sensor element (for cytotoxicity testing). The system has worked properly for terrestrial applications during the first experiments. Experiments using X-rays and UV radiation of various qualities (from UVC to UVA) have given insights into cellular mechanisms

  7. Comparison of the expression profiles induced by genotoxic and nongenotoxic carcinogens in rat liver

    Energy Technology Data Exchange (ETDEWEB)

    Ellinger-Ziegelbauer, Heidrun [Bayer Healthcare AG, Department of Molecular and Genetic Toxicology, Aprather Weg 18a, 42096 Wuppertal (Germany)]. E-mail: heidrun.ellinger-ziegelbauer@bayerhealthcare.com; Stuart, Barry [Bayer Crop Science, Department of Toxicology, Stilwell, KS (United States); Wahle, Brad [Bayer Crop Science, Department of Toxicology, Stilwell, KS (United States); Bomann, Werner [Bayer Crop Science, Department of Toxicology, Stilwell, KS (United States); Ahr, Hans Juergen [Bayer Healthcare AG, Department of Molecular and Genetic Toxicology, Aprather Weg 18a, 42096 Wuppertal (Germany)

    2005-08-04

    Application of recently developed gene expression techniques using microarrays in toxicological studies (toxicogenomics) facilitate the interpretation of a toxic compound's mode of action and may also allow the prediction of selected toxic effects based on gene expression changes. In order to test this hypothesis, we investigated whether carcinogens at doses known to induce liver tumors in the 2-year rat bioassay deregulate characteristic sets of genes in a short term in vivo study and whether these deregulated genes represent defined biological pathways. Male Wistar rats were dosed with the four nongenotoxic hepatocarcinogens methapyrilene (MPy, 60 mg/kg/day), diethylstilbestrol (DES, 10 mg/kg/day), Wy-14643 (Wy, 60 mg/kg/day), and piperonylbutoxide (PBO, 1200 mg/kg/day). After 1, 3, 7, and 14 days, the livers were taken for histopathological evaluation and for analysis of the gene expression profiles on Affymetrix RG{sub U}34A arrays. The expression profile of the four nongenotoxic carcinogens were compared to the profiles of the four genotoxic carcinogens 2-nitrofluorene (2-NF), dimethylnitrosamine (DMN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and aflatoxin B1 (AB1) from a similar study reported previously. By using statistical and clustering tools characteristically deregulated genes were extracted and functionally classified. Distinct cellular pathways were affected by the nongenotoxic carcinogens compared to the genotoxic carcinogens which at least partly correlated with the two-stage model of carcinogenesis. Characteristic to genotoxic carcinogens were a DNA damage response and the activation of proliferative and survival signaling. Nongenotoxic carcinogens showed responses to oxidative DNA or protein damage, as well as cell cycle progression and signs of regeneration. Many of the gene alterations found with the nongenotoxic carcinogens imply compound-specific mechanisms. Although neither a single gene nor a single pathway will be

  8. Monitoring genotoxic exposure in uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Sram, R.J.; Vesela, D.; Vesely, D. [Institute of Experimental Medicine, Prague (Czech Republic)] [and others

    1993-10-01

    Recent data from deep uranium mines in Czechoslovakia indicated that miners are exposed to other mutagenic factors in addition to radon daughter products. Mycotoxins were identified as a possible source of mutagens in these mines. Mycotoxins were examined in 38 samples from mines and in throat swabs taken from 116 miners and 78 controls. The following mycotoxins were identified from mines samples: aflatoxins B{sub 1} and G1, citrinin, citreoviridin, mycophenolic acid, and sterigmatocystin. Some mold strains isolated from mines and throat swabs were investigated for mutagenic activity by the SOS chromotest and Salmonella assay with strains TA100 and TA98. Mutagenicity was observed, especially with metabolic activation in citro. These data suggest that mycotoxins produced by molds in uranium mines are a new genotoxic factor im uranium miners. 17 refs., 4 tabs.

  9. DNA Damage Caused By Pesticide-contaminated Soil

    Institute of Scientific and Technical Information of China (English)

    K.KRISHNAMURTHI; S. SARAVANA DEVI; T. CHAKRABARTI

    2006-01-01

    Objective To determine the DNA damaging potential and the genotoxicity of individual compounds in pesticide contaminated soil. Methods In the present study, DNA damaging potential of pesticide-contaminated soil and the genotoxicity of individual compounds present in the soil were assessed using fluorimetric analysis of DNA unwinding assay. Results The contaminated soil sample showed 79% (P<0.001) of DNA strand break, whereas technical grade of major carbaryl and α-naphthol constituents of the contaminated soil showed 64% (P<0.01) and 60% (P<0.02) damage respectively. Conclusion Our results indicate that the toxicity caused by contaminated soil is mainly due to carbaryl and α -napthol, which are the major constituents of the soil sample analyzed by GC-MS.

  10. In vitro genotoxicity of pyridine in human lymphocytes.

    Science.gov (United States)

    Emelnsia, Aida D; Rather, Irfan A

    2016-05-01

    This work was carried out to study the genotoxicity of pyridine in vitro on human leucocyte culture. Cyclophosphamide, a well-known carcinogen was used as positive control. The four different concentrations of pyridine and cyclophosphamide showed breaks and pulverization of chromosomes in dose dependent manner. Higher number of pulverization was observed with higher concentration of pyridine (3.25μg/mL). Based on this data, our results confirm that both pyridine and its precursor showed genotoxicity against human lymphocytes.

  11. In vivo genotoxicity assessment of sertraline by using alkaline comet assay and the cytokinesis-block micronucleus assay.

    Science.gov (United States)

    Battal, Dilek; Aktas, Ayca; Sungur, Mehmet Ali; Kadioglu, Ela; Eker, Ebru Derici; Sahin, Nefise Ozlen; Saygi, Sahan

    2013-11-01

    Sertraline, a leading antidepressant in the selective serotonin reuptake inhibitor (SSRI) group of medicine, is the most frequently prescribed drug. In this study, the alkaline comet assay and the cytokinesis-block micronucleus (CBMN) assay were used to investigate genotoxicity potential of sertraline in the peripheral blood lymphocytes (PBLs) of acute and chronic sertraline-treated Wistar albino rats. Male Wistar albino rats (n = 48) were administered low, medium and high doses of sertraline (10, 40, 80 mg/kg) for acute and chronic treatment by employing the gavage method to investigate genotoxicity of the administered drug. The data (tail length, tail intensity and tail moment) were analysed and indicated that there was no statistically significant difference between sertraline-treated groups and the negative control group with respect to DNA damage (p > 0.05). However, it was observed that acute sertraline administration had caused much more DNA damage in comparison with chronic treatment (p sertraline treatment. Based on the outcome of comet assay, detection of statistically insignificant DNA damage may be due to the fact that sertraline did not cause damage on DNA. Also, increase in frequency of MN in chronic sertraline treatment suggests that chronic sertraline administration might influence some mechanisms of cell division. Therefore, dose adjustment in depressed patients seems significant as it may help prevent further prognosis of the diseases.

  12. Genotoxic and antigenotoxic effects of Fucus vesiculosus extract on cultured human lymphocytes using the chromosome aberration and Comet assays

    Directory of Open Access Journals (Sweden)

    Cleide Leite-Silva

    2007-01-01

    Full Text Available The brown seaweed Fucus vesiculosus (Fucales, Fucaceae was screened for its protective activity using doxorubicin-induced DNA damage in human lymphocytes. In this study, we assessed the genotoxic and antigenotoxic potential of three different concentrations (0.25, 0.5 and 1.0 mg mL-1 of F. vesiculosus aqueous extract using the chromosome aberration and Comet assays. Treatment of human lymphocyte cultures with 0.25, 0.5 and 1.0 mg mL-1 F. vesiculosus aqueous extract had no effect on the chromosome aberration frequency or on the extent of DNA damage detected by the Comet assay. The antigenotoxic effects of the extract were tested in human lymphocyte cultures treated with 15 µg mL-1 of doxorubicin, either alone or combined with the different concentrations of the extract, which was added to the cultures before, simultaneously with or after the doxorubicin. Only when lymphocytes were pre-treated with extract there was a reduction in doxorubicin-induced chromosome aberrations and DNA damage as detected by the Comet assay. These results demonstrate that F. vesiculosus aqueous extract is not genotoxic in cultured human lymphocytes and indicate that when added to lymphocyte cultures before doxorubicin it has antigenotoxic activity against doxorubicin-induced DNA damage.

  13. Non—Genotoxic Carcinogens.Approaches to Their Rish Assessment

    Institute of Scientific and Technical Information of China (English)

    J.A.CASTRO; M.I.DiazGomez; 等

    1993-01-01

    Epidemiological studies support the idea that most human cancers are related to chemicals present in the human environment.In turn,chemicals are believed to cause cancer via either genotoxic or non-genotoxic mechanisms.There were described in literature several simple rapid and inexpensive short term ests to reasonably predict the genotoxic nature of chemicals but in contrast,there is no reliable test or battery of tests available to predict the carcinogenicity of non-genotoxic compounds and this poses a major problem to their rish assessment.In addition,there are conflictive opinions about rish assessment needs for both classes of carcinogens.Some workers elieve that for non-genotoxic carcinogens,thresholds for exposure can be drawn while others do not.In this review,the reasons behind both of these opinions and the present hypotheses about the mechanism of action of non-genotoxic carcinogens are described and analyzed in relation to future needs.

  14. DNA Damage Following Pulmonary Exposure by Instillation to Low Doses of Carbon Black (Printex 90) Nanoparticles in Mice

    DEFF Research Database (Denmark)

    Kyjovska, Zdenka O.; Jacobsen, Nicklas R.; Saber, Anne T.;

    2015-01-01

    We previously observed genotoxic effects of carbon black nanoparticles at low doses relative to the Danish Occupational Exposure Limit (3.5 mg/m3). Furthermore, DNA damage occurred in broncho-alveolar lavage (BAL) cells in the absence of inflammation, indicating that inflammation is not required ....... Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society...... the comet assay. We interpret the increased DNA strand breaks occurring following these low exposure doses of NPCB as DNA damage caused by primary genotoxicity in the absence of substantial inflammation, cell damage, and acute phase response. Environ. Mol. Mutagen. 56:41-49, 2015. (c) 2014 The Authors...

  15. Genotoxic and Cytotoxic Effects of Antiretroviral Combinations in Mice Bone Marrow

    Science.gov (United States)

    2016-01-01

    Commonly used guidelines for the management of human immunodeficiency virus (HIV) infection (highly active antiretroviral therapy, HAART) include drug combinations such as tenofovir disoproxil fumarate (TDF) + lamivudine (3TC) and combivir [zidovudine (AZT) + 3TC] + efavirenz (EFV). These combinations may enhance the genotoxic effects induced by such drugs individually, since the therapy requires lifelong adherence and the drugs have unknown effects during treatment. Thus, the evaluation of the benefits and risks of HAART is of great importance. In order to assess the cytotoxic and genotoxic potential of three concentrations of each of the antiretroviral combinations TDF + 3TC (800 + 400, 1600 + 800, and 3200 + 1600 mg/kg body weight, BW) and combivir + EFV (200 + 100 + 400, 400 + 200 + 800, and 800 + 400 + 1600 mg/kg BW) after two exposure periods (24 h and 48 h), in the present study the in vivo comet assay (single-cell gel electrophoresis) and the mouse bone marrow micronucleus test were used. Neither TDF + 3TC nor combivir + EFV induced DNA damage at any concentrations tested after 24 h or 48 h using the comet assay. After 24 h, both combinations increased the micronucleus frequency at all concentrations tested. After 48 h, combivir + EFV increased the micronucleated polychromatic erythrocyte (MNPCE) frequency at the two highest concentrations tested. Polychromatic erythrocytes (PCE)/normochromatic erythrocytes (NCE) ratio was high for both combinations, suggesting that they can be mitogenic. Since genotoxicity may be related to carcinogenesis, it is necessary to conduct further studies to verify the long-term mutagenic effects of these drugs. PMID:27806085

  16. Evaluation of impairment of DNA integrity in marine gastropods (Cronia contracta) as a biomarker of genotoxic contaminants in coastal water around Goa, West coast of India.

    Science.gov (United States)

    Sarkar, A; Gaitonde, Dipak C S; Sarkar, Amit; Vashistha, D; D'Silva, Classy; Dalal, S G

    2008-10-01

    The measurement of the impairment of DNA in marine gastropod (Cronia contracta) provides an insight into the genotoxic effects of contaminants on marine organisms along the Goa coast. The impact of genotoxic contaminants on Goan coastal environment was evaluated in terms of the loss of DNA integrity (expressed as the value of 'I') in marine snails with respect to those from the reference site (Palolem) over a period from April 2004 to May 2005 using the technique of alkaline unwinding assay. The DNA integrity in marine snails was found to be significantly damaged at Dona Paula (58%), Vasco (73.5%), and Velsao (48.5%) during the monsoon period (July-August 2004). Similar trend in the loss of DNA integrity in marine gastropods was also detected during the post-monsoon (November-December 2004) and the pre-monsoon (April-May 2005) periods. The low integrities of DNA in marine gastropods at these sites can be attributed to exposure to genotoxic contaminants especially polycyclic aromatic hydrocarbons (PAHs) and toxic heavy metals (Pb, Cd, Cu, Fe, and Mn) prevalent in the marine environment as evident by their accumulation in the tissues of the marine snails inhabiting different sites along the Goa coast. The contaminant-induced DNA strand breaks in marine snails increased significantly at Dona Paula, Vasco, and Velsao clearly indicating the levels of contamination of the sites by genotoxic compounds in those regions. The genotoxic effects of contaminants were further substantiated by detection of the impairment (39%) of DNA integrity in marine snails in a field experiment in which the same species of marine snails (C. contracta) collected from the reference site, Palolem, were deployed at Dona Paula and caged for 25 days for exposure to ambient marine pollutants. The impairment of DNA integrity in marine gastropods along the Goa coast can thus act as a biomarker for marine pollution monitoring of genotoxic contaminants.

  17. Genotoxicity of agricultural soils in the vicinity of industrial area.

    Science.gov (United States)

    Ansari, Mohd Ikram; Malik, Abdul

    2009-03-17

    Soil samples from agricultural fields (cultivated) in the vicinity of industrial area of Ghaziabad City (India) were collected. In this city, wastewater coming from both industrial and domestic sources and without any treatment is used to irrigate the food crops. This practice has been polluting the soil and pollutants might reach the food chain. Gas chromatographic analysis show the presence of certain organochlorine (DDE, DDT, dieldrin, aldrin and endosulfan) and organophosphorus (dimethoate, malathion, methylparathion and chlorpyrifos) pesticides in soil samples. Samples were extracted using different solvents, i.e. methanol, chloroform, acetonitrile, hexane and acetone (all were HPLC-grade, SRL, India), and the extracts were assayed for genotoxic potential using Ames Salmonella/microsome test, DNA repair defective mutants and bacteriophage lambda systems. TA98 and TA100 were found to be the most sensitive strains to all the soil extracts tested. Methanol extracts exhibited a maximum mutagenicity with TA98 strain {540 (-S9) and 638 (+S9) revertants/g of soil} and 938 (-S9) and 1008 (+S9) revertants/g of soil with TA100 strain. The damage in the DNA repair defective mutants was found maximum with methanolic extract followed by acetonitrile, chloroform, hexane and acetone at the dose level of 40 microl/ml culture after 6h of treatment. The survival was 25, 30, 32, 33 and 35% in polA strain after 6h of treatment when tested with wastewater irrigated soil extracts of methanol, acetonitrile, chloroform, hexane and acetone, respectively. A significant decrease in the plaque forming units of bacteriophage lambda was also observed when treated with 40 microl of test samples. Present results showed that methanolic extracts of soil were more toxic than other soil extracts. The soil is accumulating a large number of pollutants due to wastewater irrigation and this practice of accumulation has an impact on soil health.

  18. Genotoxicity Evaluation of Irrigative Wastewater from Shijiazhuang City in China.

    Directory of Open Access Journals (Sweden)

    Xuehui Liu

    Full Text Available In the present study, the wastewater sample collected from the Dongming discharging river in Shijiazhuang city was analysed using both chemical analysis and biological assays including the Salmonella mutagenicity test, micronucleus test and single-cell gel electrophoresis. Chemical analysis of the sample was performed using gas chromatography mass spectrometry and inductively coupled plasma mass spectrometry. The Salmonella mutagenicity test was performed on Salmonella typhimurium TA97, TA98, TA100 and TA102 strains with and without S9 mixture. The mice received the wastewater in natura through drinking water at concentrations of 25%, 50%, and 100%. One group of mice was exposed for 2 consecutive days, and the other group of mice was exposed for 15 consecutive days. To establish the levels of primary DNA damage, single-cell gel electrophoresis was performed on treated mouse liver cell. The concentrations of chromium and lead in the sample exceeded the national standard (GB20922-2007 by 0.78 and 0.43-fold, respectively. More than 30 organic compounds were detected, and some of the detected compounds were mutagens, carcinogens and environmental endocrine disrupters. A positive response for Salmonella typhimurium TA98 strain was observed. Mouse exposure via drinking water containing 50% and 100% of wastewater for 15 consecutive days caused a significant increase of MN frequencies in a dose-response manner. Mouse exposure via drinking water containing 50% and 100% of wastewater for 15 consecutive days caused a significant increase of the Olive tail moments in a dose-response manner. All the results indicated that the sample from the Dongming discharging river in Shijiazhuang city exhibited genotoxicity and might pose harmful effects on the local residents.

  19. Use of a standardized JaCVAM in vivo rat comet assay protocol to assess the genotoxicity of three coded test compounds; ampicillin trihydrate, 1,2-dimethylhydrazine dihydrochloride, and N-nitrosodimethylamine.

    Science.gov (United States)

    McNamee, J P; Bellier, P V

    2015-07-01

    As part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiative international validation study of the in vivo rat alkaline comet assay (comet assay), our laboratory examined ampicillin trihydrate (AMP), 1,2-dimethylhydrazine dihydrochloride (DMH), and N-nitrosodimethylamine (NDA) using a standard comet assay validation protocol (v14.2) developed by the JaCVAM validation management team (VMT). Coded samples were received by our laboratory along with basic MSDS information. Solubility analysis and range-finding experiments of the coded test compounds were conducted for dose selection. Animal dosing schedules, the comet assay processing and analysis, and statistical analysis were conducted in accordance with the standard protocol. Based upon our blinded evaluation, AMP was not found to exhibit evidence of genotoxicity in either the rat liver or stomach. However, both NDA and DMH were observed to cause a significant increase in % tail DNA in the rat liver at all dose levels tested. While acute hepatoxicity was observed for these compounds in the high dose group, in the investigators opinion there were a sufficient number of consistently damaged/measurable cells at the medium and low dose groups to judge these compounds as genotoxic. There was no evidence of genotoxicity from either NDA or DMH in the rat stomach. In conclusion, our laboratory observed increased DNA damage from two blinded test compounds in rat liver (later identified as genotoxic carcinogens), while no evidence of genotoxicity was observed for the third blinded test compound (later identified as a non-genotoxic, non-carcinogen). This data supports the use of a standardized protocol of the in vivo comet assay as a cost-effective alternative genotoxicity assay for regulatory testing purposes.

  20. Damage Distributions

    DEFF Research Database (Denmark)

    Lützen, Marie

    2001-01-01

    the damage location, the damage sizes and the main particulars of the struck vessel. From the numerical simulation and the analyse of the damage statistics it is found that the current formulation from the IMO SLF 43/3/2 can be used as basis for determination of the p-, r-, and v-factors. Expressions...... and methods of calculation have been discussed. The damage distributions for the different vessels have been compared and analyses regarding relations between damage parameters and main particulars have been performed. The damage statistics collected in work package 1 have been analysed for relations between...... for the distribution of the non-dimensional damage location, the non-dimensional damage length and the non-dimensional penetrations have been derived. These distributions have been used as basis for a proposal for the p- and r-factors. Two proposals for the v-factor have been performed using the damage statistics...

  1. DNA Damage by Radiation in Tradescantia Leaf Cells

    Energy Technology Data Exchange (ETDEWEB)

    Han, Min; Hyun, Kyung Man; Ryu, Tae Ho; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Advanced Radiation Technology Institute, Jeongeup (Korea, Republic of); Nili, Mohammad [Dawnesh Radiation Research Institute, Barcelona (Spain)

    2010-04-15

    The comet assay is currently used in different areas of biological sciences to detect DNA damage. The comet assay, due to its simplicity, sensitivity and need of a few cells, is ideal as a short-term genotoxicity test. The comet assay can theoretically be applied to every type of eukaryotic cell, including plant cells. Plants are very useful as monitors of genetic effects caused by pollution in the atmosphere, water and soil. Tradescantia tests are very useful tools for screening the mutagenic potential in the environment. Experiments were conducted to study the genotoxic effects of ionizing radiations on the genome integrity, particularly of Tradescantia. The increasingly frequent use of Tradescantia as a sensitive environmental bioindicator of genotoxic effects. This study was designed to assess the genotoxicity of ionizing radiation using Tradescnatia-comet assay. The development of comet assay has enabled investigators to detect DNA damage at the levels of cells. To adapt this assay to plant cells, nuclei were directly obtained from Tradescantia leaf samples. A significant dose-dependent increase in the average tail moment values over the negative control was observed. Recently the adaptation of this technique to plant cells opens new possibilities for studies in variety area. The future applications of the comet assay could impact some other important areas, certainly, one of the limiting factors to its utility is the imagination of the investigator.

  2. Effects of seven chemicals on DNA damage in the rat urinary bladder: a comet assay study.

    Science.gov (United States)

    Wada, Kunio; Yoshida, Toshinori; Takahashi, Naofumi; Matsumoto, Kyomu

    2014-07-15

    The in vivo comet assay has been used for the evaluation of DNA damage and repair in various tissues of rodents. However, it can give false-positive results due to non-specific DNA damage associated with cell death. In this study, we examined whether the in vivo comet assay can distinguish between genotoxic and non-genotoxic DNA damage in urinary bladder cells, by using the following seven chemicals related to urinary bladder carcinogenesis in rodents: N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), glycidol, 2,2-bis(bromomethyl)-1,3-propanediol (BMP), 2-nitroanisole (2-NA), benzyl isothiocyanate (BITC), uracil, and melamine. BBN, glycidol, BMP, and 2-NA are known to be Ames test-positive and they are expected to produce DNA damage in the absence of cytotoxicity. BITC, uracil, and melamine are Ames test-negative with metabolic activation but have the potential to induce non-specific DNA damage due to cytotoxicity. The test chemicals were administered orally to male Sprague-Dawley rats (five per group) for each of two consecutive days. Urinary bladders were sampled 3h after the second administration and urothelial cells were analyzed by the comet assay and subjected to histopathological examination to evaluate cytotoxicity. In the urinary bladders of rats treated with BBN, glycidol, and BMP, DNA damage was detected. In contrast, 2-NA induced neither DNA damage nor cytotoxicity. The non-genotoxic chemicals (BITC, uracil, and melamine) did not induce DNA damage in the urinary bladders under conditions where some histopathological changes were observed. The results indicate that the comet assay could distinguish between genotoxic and non-genotoxic chemicals and that no false-positive responses were obtained.

  3. Assessment of Cr(VI-induced cytotoxicity and genotoxicity using high content analysis.

    Directory of Open Access Journals (Sweden)

    Chad M Thompson

    Full Text Available Oral exposure to high concentrations of hexavalent chromium [Cr(VI] induces intestinal redox changes, villus cytotoxicity, crypt hyperplasia, and intestinal tumors in mice. To assess the effects of Cr(VI in a cell model relevant to the intestine, undifferentiated (proliferating and differentiated (confluent Caco-2 cells were treated with Cr(VI, hydrogen peroxide or rotenone for 2-24 hours. DNA damage was then assessed by nuclear staining intensity of 8-hydroxydeoxyguanosine (8-OHdG and phosphorylated histone variant H2AX (γ-H2AX measured by high content analysis methods. In undifferentiated Caco-2, all three chemicals increased 8-OHdG and γ-H2AX staining at cytotoxic concentrations, whereas only 8-OHdG was elevated at non-cytotoxic concentrations at 24 hr. Differentiated Caco-2 were more resistant to cytotoxicity and DNA damage than undifferentiated cells, and there were no changes in apoptotic markers p53 or annexin-V. However, Cr(VI induced a dose-dependent translocation of the unfolded protein response transcription factor ATF6 into the nucleus. Micronucleus (MN formation was assessed in CHO-K1 and A549 cell lines. Cr(VI increased MN frequency in CHO-K1 only at highly cytotoxic concentrations. Relative to the positive control Mitomycin-C, Cr(VI only slightly increased MN frequency in A549 at mildly cytotoxic concentrations. The results demonstrate that Cr(VI genotoxicity correlates with cytotoxic concentrations, and that H2AX phosphorylation occurs at higher concentrations than oxidative DNA damage in proliferating Caco-2 cells. The findings suggest that in vitro genotoxicity of Cr(VI is primarily oxidative in nature at low concentrations. Implications for in vivo intestinal toxicity of Cr(VI will be discussed.

  4. Assessment of Cr(VI)-Induced Cytotoxicity and Genotoxicity Using High Content Analysis

    Science.gov (United States)

    Thompson, Chad M.; Fedorov, Yuriy; Brown, Daniel D.; Suh, Mina; Proctor, Deborah M.; Kuriakose, Liz; Haws, Laurie C.; Harris, Mark A.

    2012-01-01

    Oral exposure to high concentrations of hexavalent chromium [Cr(VI)] induces intestinal redox changes, villus cytotoxicity, crypt hyperplasia, and intestinal tumors in mice. To assess the effects of Cr(VI) in a cell model relevant to the intestine, undifferentiated (proliferating) and differentiated (confluent) Caco-2 cells were treated with Cr(VI), hydrogen peroxide or rotenone for 2–24 hours. DNA damage was then assessed by nuclear staining intensity of 8-hydroxydeoxyguanosine (8-OHdG) and phosphorylated histone variant H2AX (γ-H2AX) measured by high content analysis methods. In undifferentiated Caco-2, all three chemicals increased 8-OHdG and γ-H2AX staining at cytotoxic concentrations, whereas only 8-OHdG was elevated at non-cytotoxic concentrations at 24 hr. Differentiated Caco-2 were more resistant to cytotoxicity and DNA damage than undifferentiated cells, and there were no changes in apoptotic markers p53 or annexin-V. However, Cr(VI) induced a dose-dependent translocation of the unfolded protein response transcription factor ATF6 into the nucleus. Micronucleus (MN) formation was assessed in CHO-K1 and A549 cell lines. Cr(VI) increased MN frequency in CHO-K1 only at highly cytotoxic concentrations. Relative to the positive control Mitomycin-C, Cr(VI) only slightly increased MN frequency in A549 at mildly cytotoxic concentrations. The results demonstrate that Cr(VI) genotoxicity correlates with cytotoxic concentrations, and that H2AX phosphorylation occurs at higher concentrations than oxidative DNA damage in proliferating Caco-2 cells. The findings suggest that in vitro genotoxicity of Cr(VI) is primarily oxidative in nature at low concentrations. Implications for in vivo intestinal toxicity of Cr(VI) will be discussed. PMID:22905163

  5. Extract of Lillium candidum L. Can Modulate the Genotoxicity of the Antibiotic Zeocin

    Directory of Open Access Journals (Sweden)

    Peter Bryant

    2011-12-01

    Full Text Available Lilium candidum L. extract (LE is well known in folk medicine for the treatment of burns, ulcers, inflammations and for healing wounds. This work aims to clarify whether the genotoxic potential of the radiomimetic antibiotic zeocin (Zeo could be modulated by LE. Our results indicate that LE exerts no cytotoxic, DNA-damaging and clastogenic activity in in Chlamydomonas reinhardtii, Pisum sativum L. and Hordeum vulgare L. test systems over a broad concentration range. Weak but statistically significant clastogenic effects due to the induction of micronuclei and chromosome aberrations have been observed in H. vulgare L. after treatment with 200 and 300 μg/mL LE. To discriminate protective from adverse action of LE different experimental designs have been used. Our results demonstrate that the treatment with mixtures of LE and Zeo causes an increase in the level of DNA damage, micronuclei and “metaphases with chromatid aberrations” (MwA. Clear evidence has been also obtained indicating that pretreatment with LE given 4 h before the treatment with Zeo accelerates the rejoining kinetics of Zeo-induced DNA damage in P. sativum L. and C. reinhardtii, and can decrease clastogenic effect of Zeo measured as frequencies of micronuclei and MwA in H. vulgare L. Here, we show for the first time that LE can modulate the genotoxic effects of zeocin. The molecular mode of action strongly depends on the experimental design and varies from synergistic to protective effect (adaptive response–AR. Our results also revealed that LE-induced AR to zeocin involves up-regulation of DSB rejoining in C. reinhardtii and P. sativum L. cells.

  6. Genotoxicity in child populations exposed to Polycyclic Aromatic Hydrocarbons (PAHs in the air from Tabasco, Mexico

    Directory of Open Access Journals (Sweden)

    Aldeco R. Gamboa

    2008-12-01

    Full Text Available The economy of the state of Tabasco is based on oil extraction. However, this imposes major effects to the environment and communities. Examples are the Polycyclic Aromatic Hydrocarbons (PAHs that may be found in the soil, water and sediment of the region. Their volatility makes them available to living beings and results in genotoxic activity. The purpose of this study was to quantify the levels of PAHs in the air at several points in the state, and to analyze their relationship with possible damage to DNA on local inhabitants. Single Cell Gel Electrophoresis Assay (Comet Assay was applied to peripheral blood lymphocytes of five groups of children between six and 15 years of age. PAH samples were analyzed following US/EPA TO-13-A method. Results indicated the presence in the air of most of the 16 PAHs considered as high priority by EPA, some of which have been reported with carcinogenic activity. Differences (p<0.05 were found between PAHs concentration in the gaseous component and in the particulate component of air samples, with the greatest values for the gaseous component. Greatest PAH concentrations were detected in areas with high oil extraction activities. Children groups from high oil activity areas presented genotoxic damage labeled from moderate to high according to DNA migration from nuclei (Tail Length: 14.2 - 42.14 mm and Tail/Head: 0.97 - 2.83 mm compared with control group (12.25 and 0.63 mm, respectively. The group with greatest cell damage was located in the area with the greatest oil activity. We conclude that the presence of PAHs in the air may represent a health risk to populations that are chronically exposed to them at high oil activity regions.

  7. Genotoxicity in child populations exposed to polycyclic aromatic hydrocarbons (PAHs) in the air from Tabasco, Mexico.

    Science.gov (United States)

    Gamboa, Rodríguez T; Gamboa, Aldeco R; Bravo, Alvarez H; Ostrosky, Wegman P

    2008-12-01

    The economy of the state of Tabasco is based on oil extraction. However, this imposes major effects to the environment and communities. Examples are the Polycyclic Aromatic Hydrocarbons (PAHs) that may be found in the soil, water and sediment of the region. Their volatility makes them available to living beings and results in genotoxic activity. The purpose of this study was to quantify the levels of PAHs in the air at several points in the state, and to analyze their relationship with possible damage to DNA on local inhabitants. Single Cell Gel Electrophoresis Assay (Comet Assay) was applied to peripheral blood lymphocytes of five groups of children between six and 15 years of age. PAH samples were analyzed following US/EPA TO-13-A method. Results indicated the presence in the air of most of the 16 PAHs considered as high priority by EPA, some of which have been reported with carcinogenic activity. Differences (p<0.05) were found between PAHs concentration in the gaseous component and in the particulate component of air samples, with the greatest values for the gaseous component. Greatest PAH concentrations were detected in areas with high oil extraction activities. Children groups from high oil activity areas presented genotoxic damage labeled from moderate to high according to DNA migration from nuclei (Tail Length: 14.2 - 42.14 microm and Tail/Head: 0.97 - 2.83 microm) compared with control group (12.25 and 0.63 microm, respectively). The group with greatest cell damage was located in the area with the greatest oil activity. We conclude that the presence of PAHs in the air may represent a health risk to populations that are chronically exposed to them at high oil activity regions.

  8. Uranium induces apoptosis and is genotoxic to normal rat kidney (NRK-52(E)) proximal cells

    Energy Technology Data Exchange (ETDEWEB)

    Thiebault, C.; Carriere, M.; Milgram, S.; Simon, A.; Avoscan, L.; Gouget, B. [CEA Saclay, CNRS, UMR 9956, Lab Pierre Sue, F-91191 Gif Sur Yvette, (France)

    2007-07-01

    Uranium (U) is a heavy metal used in the nuclear industry and for military applications. U compounds are toxic. Their toxicity is mediated either by their radioactivity or their chemical properties. Mammalian kidneys and bones are the main organs affected by U toxicity. Although the most characteristic response to U exposure is renal dysfunction, little information is available on the mechanisms of its toxicity at the molecular level. This report studied the genotoxicity of U. Apoptosis induction in normal rat kidney (NRK-52(E)) proximal cells was investigated as a function of exposure time or concentrations (0-800 {mu}M). In parallel, DNA damage was evaluated by several methods. In order to distinguish between the intrinsic and the extrinsic pathways of apoptosis, caspases-8, -9, -10 assays were conducted and the mitochondrial membrane potential was measured. Three methods were selected for their complementarities in the detection of genetic lesions. The comet assay was used for the detection of primary lesions of DNA. {gamma}-H2AX immunostaining was achieved to detect DNA double-strand breaks. The micronucleus assay was used to detect chromosomic breaks or losses. DNA damage and apoptosis were observed in a concentration-dependent manner. This study demonstrated that U is genotoxic from 300 {mu}M and induces caspase dependent apoptosis cell death from 200 {mu}M mainly through the intrinsic pathway in NRK-52(E) cells. These results suggest that the DNA damage caused by U is reversible at low concentration (200-400 {mu}M) but becomes irreversible and leads to cell death for higher concentrations (500-800 {mu}M). (authors)

  9. Genotoxic effect induced by a magnetic field of 200 micro tesla: experimental model in vivo; Efecto genotoxico inducido por un campo magnetico de 200 microteslas: modelo experimental in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Montoya Navarro, I.; Alcaraz Saura, M.; Alcaraz Fernandez, M. D.; Olmos Ortiz, E.; Montalban Leon, F.; Sanchez Villalobos, J. M.; Alcaraz Banos, M.

    2011-07-01

    This study aims to determine the existence of a possible genotoxic (mutagenic) induced by continuous exposure to a magnetic field of 200 {+-} 20 {+-} Teslas and evaluate a possible protective effect of different antioxidants considered protective against chromosomal damage induced by ionizing radiation.

  10. Assessing of genotoxicity of 16 centralized source-waters in China by means of the SOS/umu assay and the micronucleus test: initial identification of the potential genotoxicants by use of a GC/MS method and the QSAR Toolbox 3.0.

    Science.gov (United States)

    Ye, Yan; Weiwei, Jiang; Na, Li; Mei, Ma; Donghong, Wang; Zijian, Wang; Kaifeng, Rao

    2014-03-15

    Only few studies were conducted to assess genotoxicity of centralized source waters in China and almost none of them dealt with the causal relationship between the genotoxic effect and genotoxicants. In this work, 16 centralized source waters in China were sampled from five river systems and genotoxicity of their organic extracts was assessed by use of the SOS/umu test for DNA-damaging effect and the miniaturized flow cytometry-based micronucleus (MN) test for chromosome-damaging effect. In addition, initial identification of potential genotoxicants for the six samples from the Yangtze River was done with a GC/MS method and the QSAR toolbox 3.0. The results demonstrate that eight samples showed both indirect and direct DNA-damaging effects, another four samples showed only indirect DNA-damaging effects, while chromosome-damaging effects were found for 14 out of the 16 samples, in which aneugenic and clastogenic modes of action were found for 4 and 10 samples, respectively. Both direct/indirect DNA-damaging effects and chromosome-damaging effects were induced by the six Yangtze River samples, and the existing different types of genotoxicant confirmed the results. Furthermore, o-phenylphenol was initially identified as the major cause for the DNA-damaging effects while PAHs, pesticides, phenol and anthraquinone were identified as ubiquitous chromosome-damaging agents among these samples. In conclusion, a combination of the SOS/umu test and the miniaturized flow cytometry-based MN test to detect both DNA-damaging and chromosome-damaging effects could be used as a comprehensive genotoxicity assessment tool for the evaluation and classification of genotoxicity of complex mixtures, and potential genotoxicants can be initially identified with additional information from chemical analysis and the QSAR toolbox.

  11. Toxicity and genotoxicity of the quaternary ammonium compound benzalkonium chloride (BAC) using Daphnia magna and Ceriodaphnia dubia as model systems.

    Science.gov (United States)

    Lavorgna, Margherita; Russo, Chiara; D'Abrosca, Brigida; Parrella, Alfredo; Isidori, Marina

    2016-03-01

    The toxicity and genotoxicity of the cationic surfactant benzalkonium chloride (BAC) were studied using Daphnia magna and Ceriodaphnia dubia as model systems. Acute and chronic toxicity testing were performed according to the international standard guidelines and the genotoxicity was detected through the comet assay on cells from whole organisms in vivo exposed. Acute effects occurred at concentrations in the order of tens of μg/L in D. magna and hundreds of μg/L in C. dubia. Chronic effects were found at one order of magnitude less than short-term effects maintaining the same difference in sensitivity between D. magna and C. dubia. BAC induced relevant DNA damage, in both cladocerans; the lowest adverse effect levels were 0.4 and 4 ng/L for D. magna and C. dubia, respectively. As these effective concentrations are far lower than BAC occurrence in surface waters (units of μg/L) a concerning environmental risk cannot be excluded. The findings of this study showed that D. magna and C. dubia, could be used as model organisms to detect acute and chronic toxicity as well as genotoxicity at the whole organism level.

  12. Molecular and structural changes induced by essential oils treatments in Vicia faba roots detected by genotoxicity testing.

    Science.gov (United States)

    Sturchio, Elena; Boccia, Priscilla; Zanellato, Miriam; Meconi, Claudia; Donnarumma, Lucia; Mercurio, Giuseppe; Mecozzi, Mauro

    2016-01-01

    Over the last few years, there has been an increased interest in exploiting allelopathy in organic agriculture. The aim of this investigation was to examine the effects of essential oil mixtures in order to establish their allelopathic use in agriculture. Two mixtures of essential oils consisting respectively of tea tree oil (TTO) and clove plus rosemary (C + R) oils were tested. Phytotoxicity and genotoxicity tests on the root meristems of Vicia faba minor were performed. A phytotoxic influence was particularly relevant for C + R mixture, while genotoxicity tests revealed significant results with both C + R oil mixture and TTO. Phenotypic analysis on Vicia faba minor primary roots following C + R oil mixture treatment resulted in callose production, an early symptom attributed to lipid peroxidation. The approach described in this study, based on genotoxicity bioassays, might identify specific DNA damage induced by essential oil treatments. These tests may represent a powerful method to evaluate potential adverse effects of different mixtures of essential oils that might be useful in alternative agriculture. Future studies are focusing on the positive synergism of more complex mixtures of essential oils in order to reduce concentrations of potentially toxic components while at the same time maintaining efficacy in antimicrobial and antifungal management.

  13. Genotoxicity assessment of propyl thiosulfinate oxide, an organosulfur compound from Allium extract, intended to food active packaging.

    Science.gov (United States)

    Mellado-García, P; Maisanaba, S; Puerto, M; Llana-Ruiz-Cabello, M; Prieto, A I; Marcos, R; Pichardo, S; Cameán, A M

    2015-12-01

    Essential oils from onion (Allium cepa L.), garlic (Allium sativum L.), and their main components, such as propyl thiosulfinate oxide (PTSO) are being intended for active packaging with the purpose of maintaining and extending food product quality and shelf life. The present work aims to assess for the first time the potential mutagenicity/genotoxicity of PTSO (0-50 µM) using the following battery of genotoxicity tests: (1) the bacterial reverse-mutation assay in Salmonella typhimurium (Ames test, OECD 471); (2) the micronucleus test (OECD 487) (MN) and (3) the mouse lymphoma thymidine-kinase assay (OECD 476) (MLA) on L5178YTk(+/-), cells; and (4) the comet assay (with and without Endo III and FPG enzymes) on Caco-2 cells. The results revealed that PTSO was not mutagenic in the Ames test, however it was mutagenic in the MLA assay after 24 h of treatment (2.5-20 µM). The parent compound did not induce MN on mammalian cells; however, its metabolites (in the presence S9) produced positive results (from 15 µM). Data from the comet assay indicated that PTSO did not induce DNA breaks or oxidative DNA damage. Further in vivo genotoxicity tests are needed to confirm its safety before it is used as active additive in food packaging.

  14. Genotoxicity test of propolis extract, mineral trioksida aggregat, and calcium hydroxide on fibroblast BHK-21 cell cultures

    Directory of Open Access Journals (Sweden)

    Ceples Dian Kartika W.P

    2015-03-01

    Full Text Available Background: Health industry has always used natural products as an alternative. Propolis, a natural antibiotic, is a resinous yellow brown or dark brown substance derived from honey bees (Apis mellifera. The main chemical compounds contained in propolis are flavonoids, phenolics and other various aromatic compounds. Flavonoids are well known plant compounds that have antibacterial, antifungal, antiviral, antioxidant and anti-inflammatory proprieties. Propolis is expected to be an alternative used for root canal treatment with lower toxicity compared to calcium hydroxide (Ca(OH2 . Over the last decade, a new material, mineral trioxide aggregate (MTA was developed, and has been used as the gold standard. All materials used in mouth should be biocompatible. The initial level of material biocompatibility evaluation involves toxicity and genotoxicity tests. Purpose: This research is aimed to conduct comparison test of genotoxicity effect of propolis extract, MTA and Ca(OH2 on fibroblast BHK-21 cell culture. Methods: This research was conducted with single-cell gel electrophoresis method. Results: The results indicate that propolis extract cannot cause DNA damage, while MTA can cause apoptosis and Ca(OH2 can cause neucrosis. Conclusion: It can be concluded that propolis extract has genotoxicity effect lower than MTA and Ca(OH2 , but MTA has lower effect on fibroblast BHK-21 cell culture.

  15. A new approach for the oocyte genotoxicity assay: adaptation of comet assay on mouse cumulus-oocyte complexes.

    Science.gov (United States)

    Greco, F; Perrin, J; Auffan, M; Tassistro, V; Orsière, T; Courbiere, B

    2015-07-01

    Conventional genotoxicity tests are technically difficult to apply to oocytes, and results obtained on somatic cells cannot be extrapolated to gametes. We have previously described a comet assay (original-CA) on denuded mouse oocytes, but, in vivo, oocytes are not isolated from their surrounding follicular cells. Our objective was to develop a comet assay on cumulus-oocyte complexes (COC-CA) for a more physiological approach to study the genotoxicity of environmental factors on oocytes. For COC-CA, whole COC were exposed directly to exogenous agents after ovulation and removal from oviducts. Three conditions were studied: a negative control group, and two positive control groups, one of which was exposed to hydrogen peroxide (H2O2) and the other group was incubated with cerium dioxide nanoparticles (CeO2 NPs). With both tests, DNA damage was significant in the presence of both H2O2 and CeO2 NPs compared with the negative control. COC-CA offers an interesting tool for assaying the genotoxicity of environmental agents towards germinal cells. Furthermore, COC-CA is less time-consuming and simplifies the protocol of the original-CA, because COC-CA is easier to perform without the washing-out procedure.

  16. Determination of the mutagenic and genotoxic potential of simulated leachate from an automobile workshop soil on eukaryotic system.

    Science.gov (United States)

    Alabi, Okunola Adenrele; Omosebi, Omotoyosi; Chizea, Ifychukwwu

    2015-07-01

    Contamination of soil and water bodies with spent engine oil and petroleum products is a serious ecological problem, primarily in the automobile workshops and garages. This has potential short and chronic adverse health risks. Information is currently scarce on the potential mutagenicity and genotoxicity of such wastes. In this study, the potential mutagenic and genotoxic effects of simulated leachate from automobile workshop soil in Sagamu, Ogun state, Nigeria, were investigated. The assays utilized were bone marrow micronucleus (MN) and chromosome aberration (CA), sperm morphology and sperm count in mice. The physicochemical analysis of the leachate was also carried out. Experiments were carried out at concentrations of 1, 5, 10, 25, 50, 75 and 100% (volume per volume; leachate:distilled water) of the leachate sample. MN analysis showed a concentration-dependent induction of micronucleated polychromatic erythrocytes across the treatment groups. In the CA test, there was concentration-dependent significant reduction in mitotic index and induction of different types of CAs. Assessment of sperm shape showed a significant increase in sperm abnormalities with significant decrease in mean sperm count in treated groups. Heavy metals analyzed in the tested sample are believed to contribute significantly to the observed genetic damage. This indicates that automobile workshop soil-simulated leachate contains potential genotoxic agents and constitutes a genetic risk in exposed human population.

  17. Patterns of scAAV vector insertion associated with oncogenic events in a mouse model for genotoxicity.

    Science.gov (United States)

    Rosas, Lucia E; Grieves, Jessica L; Zaraspe, Kimberly; La Perle, Krista Md; Fu, Haiyan; McCarty, Douglas M

    2012-11-01

    Recombinant adeno-associated virus (rAAV) vectors have gained an extensive record of safety and efficacy in animal models of human disease. Infrequent reports of genotoxicity have been limited to specific vectors associated with excess hepatocellular carcinomas (HCC) in mice. In order to understand potential mechanisms of genotoxicity, and identify patterns of insertion that could promote tumor formation, we compared a self-complementary AAV (scAAV) vector designed to promote insertional activation (scAAV-CBA-null) to a conventional scAAV-CMV-GFP vector. HCC-prone C3H/HeJ mice and severe combined immunodeficiency (SCID) mice were infected with vector plus secondary treatments including partial hepatectomy (HPX) and camptothecin (CPT) to determine the effects of cell cycling and DNA damage on tumor incidence. Infection with either vector led to a significant increase in HCC incidence in male C3H/HeJ mice. Partial HPX after infection reduced HCC incidence in the cytomegalovirus-green fluorescent protein (CMV-GFP)-infected mice, but not in the cognate chicken β-actin (CBA)-null infected group. Tumors from CBA-null infected, hepatectomized mice were more likely to contain significant levels of vector DNA than tumors from the corresponding CMV-GFP-infected group. Most CBA-null vector insertions recovered from tumors were associated with known proto-oncogenes or tumor suppressors. Specific patterns of insertion suggested read-through transcription, enhancer effects, and disruption of tumor suppressors as likely mechanisms for genotoxicity.

  18. Evaluation of cytotoxic and genotoxic activity of fungicide formulation Tango(®) Super in bovine lymphocytes.

    Science.gov (United States)

    Schwarzbacherová, Viera; Wnuk, Maciej; Lewinska, Anna; Potocki, Leszek; Zebrowski, Jacek; Koziorowski, Marek; Holečková, Beáta; Šiviková, Katarína; Dianovský, Ján

    2017-01-01

    Tango(®) Super is a two-compound fungicide formulation widely employed in grain protection. However, details of Tango(®) Super effects on cell cultures have not been fully investigated. In this study, bovine lymphocytes were exposed to a concentration range 0.5; 1.5; 3; 6; and 15 μg mL(-1) for 4 h to assess the cytotoxicity and genotoxicity of the fungicide. Our experiments revealed that this fungicide treatment reduced cell viability, decreased cell proliferation and provoked apoptotic cell death. Cell cycle analysis showed predominant accumulation of cells in the G0/G1 phase of the cell cycle. The fungicide was able to induce mitochondrial superoxide production accompanied by elevated levels of carbonylated proteins and changes in the lipid membrane composition. The fungicide did not induce micronuclei production, but stimulated both DNA double-strand breaks and the formation of p53 binding protein, which is accumulated during the DNA repair process at the site of double-strand breaks. Based on the obtained data we suppose that the fungicide-induced DNA damage is the result of oxidative stress, which may contribute to higher occurrence of apoptotic cell death. Because ergosterol biosynthesis-inhibiting fungicides are widely used in agriculture to ensure higher crop yields and may cause health impairment of animals and humans, there is a need for further testing to elucidate their potential genotoxic effects using in vivo and/or in vitro systems.

  19. Assessment of the cytotoxic, genotoxic, and mutagenic potential of Acrocomia aculeata in rats.

    Science.gov (United States)

    Traesel, G K; Castro, L H A; Silva, P V B; Muzzi, R M; Kassuya, C A L; Arena, A C; Oesterreich, S A

    2015-01-26

    Acrocomia aculeata (Jacq.) Lodd. ex Mart. is a plant species commonly used as a foodstuff and also for treating diseases, since it contains high concentrations of antioxidant compounds and monounsaturated fatty acids. Considering its ethnopharmacological relevance, the aim of the present study was to assess the cytotoxic, genotoxic, and mutagenic effects of an oil extracted from the pulp of A. aculeata (OPAC) in rats. In addition, a chromatographic characterization of the fatty acids present in OPAC was performed. Male and female Wistar rats were treated orally with 125, 250, 500, 1000, or 2000 mg/kg/body weight OPAC. The effects of OPAC ingestion were determined by performing the comet assay and micronucleus test. The comet assay data demonstrated that OPAC did not increase the frequency or rate of DNA damage in groups treated with any of the concentrations assessed compared to that in the negative control group. In the micronucleus test, the animals treated did not exhibit any cytotoxic or mutagenic changes in peripheral blood erythrocytes. The results demonstrated that OPAC did not exhibit cytotoxic, genotoxic, or mutagenic effects in Wistar rats, thereby increasing the evidence for the safety of oil extracted from this plant.

  20. Textile effluent induced genotoxic effects and oxidative stress in Clarias gariepinus.

    Science.gov (United States)

    Ayoola, S O; Bassey, B O; Alimba, C G; Ajani, E K

    2012-09-01

    Human and ecological disorder experienced in industrial settlements as a result of improper disposal of chemicals such as textile effluent calls for careful surveillance on the state of the environment. This study investigated the toxicity of textile effluent discharge using biochemical and cytogenetic responses to ascertain the acute and sub lethal effects on Clarias gariepinus. The 96 h LC50 of C. gariepinus exposed to the textile effluent was 8.203 ml L(-1). Fourteen day exposures to 1, 2, 4 and 6 ml L(-1) doses were conducted and several toxicological endpoints were evaluated. Sub lethal genotoxicity and biochemical study was also carried out for fourteen days. The genotoxicity studies utilized micronucleus test while the biochemical studies quantified serum anti-oxidant status Total Protein (TP), Catalase (CAT), Superoxide Dismutase (SOD) and Malondialdehyde (MDA) of the exposed fish. Toxicity factor indicates that the 96 h LC50 was significantly more toxic than the 24 h LC50 (p 0.05). The results obtained from this study showed that textile effluent increase cytogenetic damage and altered anti-oxidant status in C. gariepinus. Chemicals in the effluent can be bioaccumulated and biomagnified in the aquatic organism hence affecting man.

  1. GFP tracking transcriptional activity endogenous p53: vector construction and application in genotoxicity detection

    Institute of Scientific and Technical Information of China (English)

    ZENG Wei-sen; LUO Chen; XIE Wei-bing; CHEN Han-yuan

    2001-01-01

    To establish a sensitive.and specific system for genotoxicity detection in vivo. Methods: Endogenous p53 tracer vector p53RE was constructed by using green fluorescent protein (GFP) as a reporter to trace p53 transcriptional activity under the control of base SV40 early promoter. The tracer cells 3T3-REG were established by transfecting NIH3T3 cells with tracer vector and treated with ultraviolet, H202 and adriamycin to induce DNA damage and the subsequent endogenous p53 expression. The GFP expression and its green fluorescence in the tracer cells were observed and measured with fluorescent microscope and FACS. Results: The GFP expression increased rapidly after various treatment and reached the maximum 1 h later, and decreased gradually afterwards. FACS analysis showed that GFP expression in 3T3-REG tracer cells was consistent with the concentration of H202, while that in 3T3-SVG cells, which were transfected with control vector pSV-GFP, hardly increased in response to the treatment. Conclusion: GFP tracing p53 transcriptional activity is a sensitive and specific method for genotoxicity detection.

  2. Benzophenone guttiferone A from Garcinia achachairu Rusby (Clusiaceae presents genotoxic effects in different cells of mice.

    Directory of Open Access Journals (Sweden)

    Peterson Menezes Terrazas

    Full Text Available Benzophenones from natural sources and those of synthetic analogues present several reports of potent biological properties, and Guttiferone A represents a promising medicinal natural compound with analgesic and gastroprotective profiles. Considering that there are no reports that assess the genetic toxicity of Guttiferone A, the present study was undertaken to investigate the genotoxic potential of this benzophenone isolated from seeds of Garcinia achachairu in terms of DNA damage in different cells of Swiss albino mice using the comet assay, and its clastogenic/aneugenic effects in bone marrow cells in vivo by the micronucleus test. Cytotoxicity was assessed by scoring polychromatic (PCE and normochromatic (NCE erythrocytes ratio. Guttiferone A was administered by oral gavage at doses of 15, 30 and 60 mg/kg. The results showed that Guttiferone A produced genotoxic effects in leukocytes, liver, bone marrow, brain and testicle cells and clastogenic/aneugenic effects in bone marrow erythrocytes of mice. The PCE/NCE ratio indicated no cytotoxicity. Since guttiferone A is harmful to the genetic material we suggest caution in its use by humans.

  3. Genotoxicity of food preservative sodium sorbate in human lymphocytes in vitro.

    Science.gov (United States)

    Mamur, Sevcan; Yüzbaşıoğlu, Deniz; Unal, Fatma; Aksoy, Hüseyin

    2012-10-01

    The genotoxic effects of antimicrobial food additive sodium sorbate (SS) was assessed by using chromosome aberrations (CAs), sister-chromatid exchanges (SCEs), and micronucleus (MN) in cultured human lymphocytes and comet assay in isolated human lymphocytes. Lymphocytes were treated with four concentrations (100, 200, 400 and 800 μg/ml) of SS as well as a negative (sterile distilled water) and a positive control (Mitomycin-C: MMC for cultured lymphocytes and H(2)O(2) for isolated lymphocytes). The result of this study indicated that SS increased the frequency of CAs at both 24 and 48 h period compared to control. When gaps were included, this increase was significant at 200, 400 and 800 μg/ml concentrations at 24 h and, at all concentrations at 48 h treatment time. When gaps were excluded, this increase was significant at only 800 μg/ml concentration at both 24 and 48 h treatments. In addition, SS increased SCEs/cell and MN frequency at 400 and 800 μg/ml concentrations at both 24 and 48 h compared to negative control. Furthermore, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1 h in vitro exposure. The present results show that SS is genotoxic to the human peripheral blood lymphocytes in vitro at the highest concentrations.

  4. P53 alters the cytotoxicity and genotoxicity for oxidized graphene in human B-lymphoblastoid cells

    Science.gov (United States)

    Petibone, Dayton Matthew

    Widespread use of oxidized graphene nanomaterials in industry, medicine, and consumer products raises concern about potential adverse impacts on human health. The p53 tumor suppressor protein is crucial to maintaining cellular and genetic stability to prevent carcinogenesis. Here, we show that oxygen functionalized graphene (f-G) absorption and p53 functional status correlate with cytotoxicity and genotoxicity in human B-lymphoblastoid cells. Trends in f-G absorption by were dose-dependent. Cells with functional p53 exposed to f-G arrested in G0/G1 phase of the cell cycle, suppressed f-G induced reactive oxygen species (ROS), and had elevated apoptosis. While compared to p53 competent cells, the p53 deficient cells exposed to f-G accumulated in S-phase of the cell cycle, had elevated ROS levels, and evaded apoptosis. The f-G genotoxicity was evident as increased loss-of-heterozygosity mutants independent of p53 status, and structural chromosome damage in p53 deficient cells. These findings have broad implications for the safety and efficacy of oxidized graphene nanomaterials in industrial, consumer products and biomedical applications.

  5. p53 induction and cell viability modulation by genotoxic individual chemicals and mixtures.

    Science.gov (United States)

    Di Paolo, Carolina; Müller, Yvonne; Thalmann, Beat; Hollert, Henner; Seiler, Thomas-Benjamin

    2017-03-16

    The binding of the p53 tumor suppression protein to DNA response elements after genotoxic stress can be quantified by cell-based reporter gene assays as a DNA damage endpoint. Currently, bioassay evaluation of environmental samples requires further knowledge on p53 induction by chemical mixtures and on cytotoxicity interference with p53 induction analysis for proper interpretation of results. We investigated the effects of genotoxic pharmaceuticals (actinomycin D, cyclophosphamide) and nitroaromatic compounds (4-nitroquinoline 1-oxide, 3-nitrobenzanthrone) on p53 induction and cell viability using a reporter gene and a colorimetric assay, respectively. Individual exposures were conducted in the absence or presence of metabolic activation system, while binary and tertiary mixtures were tested in its absence only. Cell viability reduction tended to present direct correlation with p53 induction, and induction peaks occurred mainly at chemical concentrations causing cell viability below 80%. Mixtures presented in general good agreement between predicted and measured p53 induction factors at lower concentrations, while higher chemical concentrations gave lower values than expected. Cytotoxicity evaluation supported the selection of concentration ranges for the p53 assay and the interpretation of its results. The often used 80% viability threshold as a basis to select the maximum test concentration for cell-based assays was not adequate for p53 induction assessment. Instead, concentrations causing up to 50% cell viability reduction should be evaluated in order to identify the lowest observed effect concentration and peak values following meaningful p53 induction.

  6. Protective effect of hawthorn extract against genotoxicity induced by methyl methanesulfonate in human lymphocytes.

    Science.gov (United States)

    Hosseinimehr, Seyed Jalal; Azadbakht, Mohammad; Tanha, Mohammad; Mahmodzadeh, Aziz; Mohammadifar, Sohila

    2011-05-01

    The preventive effect of hawthorn (Crataegus microphylla) fruit extract against genotoxicity induced by methyl methanesulfonate (MMS) has been investigated in human cultured blood lymphocytes. Peripheral blood samples were collected from human volunteers at 0 (10 minutes before), and at 1 and 2 hours after a single oral ingestion of 1 g hawthorn powder extract. At each time point, the whole blood was treated in vitro with MMS (200 µmol) at 24 hours after cell culture, and then the lymphocytes were cultured with mitogenic stimulation to determine the micronuclei in cytokinesis-blocked binucleated cells. The lymphocytes treated with hawthorn and MMS to exhibit a significant decreasing in the incidence of micronucleated binucleated cells, as compared with similarly MMS-treated lymphocytes from blood samples collected at 0 hour. The maximum protection and decreasing in frequency of micronuclei (36%) was observed at 1 hour after ingestion of hawthorn extract. The high performance liquid chromatography (HPLC) analysis showed that hawthorn contained chlorogenic acid, epicatechin and hyperoside. It is obvious that hawthorn, particularly flavonoids constituents with antioxidative activity, reduced the oxidative stress and genotoxicity induced by toxic compounds. This set of data may have an important application for the protection of human lymphocyte from the genetic damage and side effects induced by chemicals hazardous in people.

  7. Dynamically regulated sumoylation of HDAC2 controls p53 deacetylation and restricts apoptosis following genotoxic stress

    Institute of Scientific and Technical Information of China (English)

    André Brandl; Tobias Wagner; Katharina M. Uhlig; Shirley K. Knauer; Roland H. Stauber; Frauke Melchior; Günter Schneider; Thorsten Heinzel; Oliver H. Kr(a)mer

    2012-01-01

    Histone deacetylase 2 (HDAC2) is relevant for homeostasis and plays a critical role in gastrointestinal cancers.Here,we report that post-translational modification of endogenous HDAC2 with small ubiquitin-related modifier 1 (SUMO1) is a new regulatory switch for the tumor suppressor p53.Sumoylation of HDAC2 at lysine 462 allows binding of HDAC2 to p53.Moreover,sumoylated HDAC2 is a previously not recognized biologically relevant site-specific deacetylase for p53.Deacetylation of p53 at lysine 320 by sumoylated HDAC2 blocks recruitment of p53 into promoter-associated complexes and p53-dependent expression of genes for cell cycle control and apoptosis.Thereby,catalytically active sumoylated HDAC2 restricts p53 functions and attenuates DNA damage-induced apoptosis.Genotoxic stress evokes desumoylation of HDAC2,enabling p53-dependent gene expression,Our data show a new molecular mechanism involving a dynamically controlled HDAC2-sumoylation/p53-acetylation switch that regulates cell fate decisions following genotoxic stress.

  8. Protective effects of boron on cyclophosphamide induced lipid peroxidation and genotoxicity in rats.

    Science.gov (United States)

    Ince, Sinan; Kucukkurt, Ismail; Demirel, Hasan Huseyin; Acaroz, Damla Arslan; Akbel, Erten; Cigerci, Ibrahim Hakki

    2014-08-01

    The aim of the present study was to evaluate the possible protective effect of boron (B) on cyclophosphamide (CYC) induced oxidative stress in rats. Totally, thirty Wistar albino male rats were fed standard rodent diet and divided into 5 equal groups: physiological saline was given intraperitoneally (i.p.) to the control group (vehicle treated), to the second group only 75 mg kg(-1) CYC was given i.p. on the 14th d, and boron was administered (5, 10, and 20 mg kg(-1), i.p.) to the other groups for 14 d and CYC (75 mg kg(-1), i.p.) on the 14th d. CYC caused increase of malondialdehyde and decrease of glutathione levels, decrease of superoxide dismutase activities in erythrocyte and tissues, decrease of erythrocyte, heart, lung, and brain catalase, and plasma antioxidant activities. Also, CYC treatment caused to DNA damage in mononuclear leukocytes. Moreover, B exhibited protective action against the CYC-induced histopathological changes in tissues. However, treatment of B decreased severity of CYC-induced lipid peroxidation and genotoxicity on tissues. In conclusion, B has ameliorative effects against CYC-induced lipid peroxidation and genotoxicity by enhancing antioxidant defence mechanism in rat.

  9. Evaluation of Cytotoxicity and Genotoxicity of Inula viscosa Leaf Extracts with Allium Test

    Directory of Open Access Journals (Sweden)

    Tülay Aşkin Çelik

    2010-01-01

    Full Text Available I. viscosa has been used for years in folk medicine for its anti-inflammatory, antipyretic, antiseptic, and paper antiphlogistic activities. In this study, cytotoxic and genotoxic effects of I. viscosa leaf extracts on the root meristem cells of Allium cepa have been examined. Onion bulbs were exposed to 2.5 mg/ml, 5 mg/ml, and 10 mg/ml concentrations of the extracts for macroscopic and microscopic analysis. Tap water has been used as a negative control and Ethyl methanesulfonate (EMS (2⋅10−2 M has been used as a positive control. The test concentrations have been determined according to doses which are recommended for use in alternative medicine. There has been statistically significant (P<.05 inhibition of root growth depending on concentration by the extracts when compared with the control groups. All the tested extracts have been observed to have cytotoxic effects on cell division in A. cepa. I. viscosa leaf extract induces the total number of chromosomal aberrations and micronuclei (MNC formations in A. cepa root tip cells significantly when compared with control groups. Also, this paper shows for the first time the induction of cell death, ghost cells, cells with membrane damage, and binucleated cells by extract treatment. These results suggest the cytotoxic and genotoxic effects of the I. viscosa leaf extracts on A. cepa.

  10. Evaluation of cytotoxicity and genotoxicity of Inula viscosa leaf extracts with Allium test.

    Science.gov (United States)

    Aşkin Celik, Tülay; Aslantürk, Ozlem Sultan

    2010-01-01

    I. viscosa has been used for years in folk medicine for its anti-inflammatory, antipyretic, antiseptic, and paper antiphlogistic activities. In this study, cytotoxic and genotoxic effects of I. viscosa leaf extracts on the root meristem cells of Allium cepa have been examined. Onion bulbs were exposed to 2.5 mg/ml, 5 mg/ml, and 10 mg/ml concentrations of the extracts for macroscopic and microscopic analysis. Tap water has been used as a negative control and Ethyl methanesulfonate (EMS) (2 * 10(-2) M) has been used as a positive control. The test concentrations have been determined according to doses which are recommended for use in alternative medicine. There has been statistically significant (P viscosa leaf extract induces the total number of chromosomal aberrations and micronuclei (MNC) formations in A. cepa root tip cells significantly when compared with control groups. Also, this paper shows for the first time the induction of cell death, ghost cells, cells with membrane damage, and binucleated cells by extract treatment. These results suggest the cytotoxic and genotoxic effects of the I. viscosa leaf extracts on A. cepa.

  11. Evaluation of phosphine genotoxicity at occupational levels of exposure in New South Wales, Australia.

    Science.gov (United States)

    Barbosa, A; Bonin, A M

    1994-10-01

    Phosphine has been claimed to cause chromosomal damage at exposures close to the current time weighted average exposure standard of 0.3 ppm (0.4 mg/m3). The current study involved 31 phosphine fumigators and 21 controls during the high fumigation season. All were volunteers and were evaluated for genotoxicity variables, including micronuclei in peripheral blood lymphocytes and urine mutagenicity. In parallel, all fumigators and 17 controls were evaluated for full haematology, multiple biochemical analysis, whole blood organochlorines, and whole blood and serum cholinesterase activity. The results for micronuclei showed no significant differences between fumigators and controls, but detected a strong association between age and increased frequency of micronuclei. Measurement of urine mutagenicity did not show any significant difference between fumigators and controls, but did show increased excretion of mutagens in smokers. All haematological and biochemical variables were within normal ranges, except for some non-specific changes in biochemistry. At monitored occupational exposures of phosphine exposure and genotoxic or toxicological effects in fumigators.

  12. Evaluation of phosphine genotoxicity at occupational levels of exposure in New South Wales, Australia.

    Science.gov (United States)

    Barbosa, A; Bonin, A M

    1994-01-01

    Phosphine has been claimed to cause chromosomal damage at exposures close to the current time weighted average exposure standard of 0.3 ppm (0.4 mg/m3). The current study involved 31 phosphine fumigators and 21 controls during the high fumigation season. All were volunteers and were evaluated for genotoxicity variables, including micronuclei in peripheral blood lymphocytes and urine mutagenicity. In parallel, all fumigators and 17 controls were evaluated for full haematology, multiple biochemical analysis, whole blood organochlorines, and whole blood and serum cholinesterase activity. The results for micronuclei showed no significant differences between fumigators and controls, but detected a strong association between age and increased frequency of micronuclei. Measurement of urine mutagenicity did not show any significant difference between fumigators and controls, but did show increased excretion of mutagens in smokers. All haematological and biochemical variables were within normal ranges, except for some non-specific changes in biochemistry. At monitored occupational exposures of phosphine exposure and genotoxic or toxicological effects in fumigators. PMID:8000496

  13. Chemopreventive effect of cactus Opuntia ficus indica on oxidative stress and genotoxicity of aflatoxin B1

    Science.gov (United States)

    2011-01-01

    Background Aflatoxin B1 (AFB1) is potent hepatotoxic and hepatocarcinogenic agent. In aflatoxicosis, oxidative stress is a common mechanism contributing to initiation and progression of hepatic damage. The aim of this work was to evaluate the hepatoprotective effect of cactus cladode extract (CCE) on aflatoxin B1-induced liver damage in mice by measuring malondialdehyde (MDA) level, the protein carbonyls generation and the heat shock proteins Hsp 70 and Hsp 27 expressions in liver. We also looked for an eventual protective effect against AFB1-induced genotoxicity as determined by chromosome aberrations test, SOS Chromotest and DNA fragmentation assay. We further evaluated the modulation of p53, bax and bcl2 protein expressions in liver. Methods Adult, healthy balbC (20-25 g) male mice were pre-treated by intraperitonial administration of CCE (50 mg/Kg.b.w) for 2 weeks. Control animals were treated 3 days a week for 4 weeks by intraperitonial administration of 250 μg/Kg.b.w AFB1. Animals treated by AFB1 and CCE were divided into two groups: the first group was administrated CCE 2 hours before each treatment with AFB1 3 days a week for 4 weeks. The second group was administrated without pre-treatment with CCE but this extract was administrated 24 hours after each treatment with AFB1 3 days a week for 4 weeks. Results Our results clearly showed that AFB1 induced significant alterations in oxidative stress markers. In addition, it has a genotoxic potential and it increased the expression of pro apoptotic proteins p53 and bax and decreased the expression of bcl2. The treatment of CCE before or after treatment with AFB1, showed (i) a total reduction of AFB1 induced oxidative damage markers, (ii) an anti-genotoxic effect resulting in an efficient prevention of chromosomal aberrations and DNA fragmentation compared to the group treated with AFB1 alone (iii) restriction of the effect of AFB1 by differential modulation of the expression of p53 which decreased as well as its

  14. Chemopreventive effect of cactus Opuntia ficus indica on oxidative stress and genotoxicity of aflatoxin B1

    Directory of Open Access Journals (Sweden)

    Ben Mansour Hédi

    2011-10-01

    Full Text Available Abstract Background Aflatoxin B1 (AFB1 is potent hepatotoxic and hepatocarcinogenic agent. In aflatoxicosis, oxidative stress is a common mechanism contributing to initiation and progression of hepatic damage. The aim of this work was to evaluate the hepatoprotective effect of cactus cladode extract (CCE on aflatoxin B1-induced liver damage in mice by measuring malondialdehyde (MDA level, the protein carbonyls generation and the heat shock proteins Hsp 70 and Hsp 27 expressions in liver. We also looked for an eventual protective effect against AFB1-induced genotoxicity as determined by chromosome aberrations test, SOS Chromotest and DNA fragmentation assay. We further evaluated the modulation of p53, bax and bcl2 protein expressions in liver. Methods Adult, healthy balbC (20-25 g male mice were pre-treated by intraperitonial administration of CCE (50 mg/Kg.b.w for 2 weeks. Control animals were treated 3 days a week for 4 weeks by intraperitonial administration of 250 μg/Kg.b.w AFB1. Animals treated by AFB1 and CCE were divided into two groups: the first group was administrated CCE 2 hours before each treatment with AFB1 3 days a week for 4 weeks. The second group was administrated without pre-treatment with CCE but this extract was administrated 24 hours after each treatment with AFB1 3 days a week for 4 weeks. Results Our results clearly showed that AFB1 induced significant alterations in oxidative stress markers. In addition, it has a genotoxic potential and it increased the expression of pro apoptotic proteins p53 and bax and decreased the expression of bcl2. The treatment of CCE before or after treatment with AFB1, showed (i a total reduction of AFB1 induced oxidative damage markers, (ii an anti-genotoxic effect resulting in an efficient prevention of chromosomal aberrations and DNA fragmentation compared to the group treated with AFB1 alone (iii restriction of the effect of AFB1 by differential modulation of the expression of p53 which

  15. Nicotine derived genotoxic effects in human primary parotid gland cells as assessed in vitro by comet assay, cytokinesis-block micronucleus test and chromosome aberrations test.

    Science.gov (United States)

    Ginzkey, Christian; Steussloff, Gudrun; Koehler, Christian; Burghartz, Marc; Scherzed, Agmal; Hackenberg, Stephan; Hagen, Rudolf; Kleinsasser, Norbert H

    2014-08-01

    Genotoxic effects of nicotine were described in different human cells including salivary gland cells. Based on the high nicotine concentration in saliva of smokers or patients using therapeutic nicotine patches, the current study was performed to evaluate the genotoxic potential of nicotine in human salivary gland cells. Therefore, primary salivary gland cells from 10 patients undergoing parotid gland surgery were exposed to nicotine concentrations between 1 μM and 1000 μM for 1 h in the absence of exogenous metabolic activation. The acinar phenotype was proven by immunofluorescent staining of alpha-amylase. Genotoxic effects were evaluated using the Comet assay, the micronucleus test and the chromosome aberration test. Cytotoxicity and apoptosis were determined by trypan blue exclusion test and Caspase-3 assay. Nicotine was able to induce genotoxic effects in all three assays. The chromosome aberration test was the most sensitive and increases in numerical and structural (chromatid-type and chromosome-type) aberrations were seen at ≥1 μM, whereas increases in micronuclei frequency were detected at 10 μM and DNA damage as measured in the Comet assay was noted at >100 μM. No cytotoxic damage or influence of apoptosis could be demonstrated. Nicotine as a possible risk factor for tumor initiation in salivary glands is still discussed controversially. Our results demonstrated the potential of nicotine to induce genotoxic effects in salivary gland cells. These results were observed at saliva nicotine levels similar to those found after oral or transdermal exposure to nicotine and suggest the necessity of careful monitoring of the use of nicotine in humans.

  16. Genotoxicity of alkene epoxides in human peripheral blood mononuclear cells and HL60 leukaemia cells evaluated with the comet assay.

    Science.gov (United States)

    Fabiani, Roberto; Rosignoli, Patrizia; De Bartolomeo, Angelo; Fuccelli, Raffaela; Morozzi, Guido

    2012-08-30

    Volatile organic compounds (VOCs) exert their carcinogenic activity through the production of epoxide metabolites. Because of their high reactivity some epoxides are also produced in the chemical industry for the synthesis of other compounds. Therefore, human exposure to VOCs epoxides does occur and may be an important human health concern. In this study, the in vitro genotoxic potential of epoxides originating from 1,3-butadiene (3,4-epoxy-1-butene: EB; 1,2:3,4-diepoxybutane: DEB), isoprene (3,4-epoxy-2-methyl-1-butene: IO), styrene (styrene-7,8-oxide: SO), propylene (propylene oxide: PO) and 1-butene (1,2-epoxy-butane: BO) in human peripheral blood mononuclear cells (PBMCs) and promyelocytic leukaemia cells (HL60) was measured with the comet assay (single-cell gel electrophoresis, SCGE). The effect of inclusion of foetal calf serum (FCS, 5%) in the cell-culture medium and different durations of exposure (2h, 24h) were also investigated. All epoxides tested produced DNA damage in a concentration range that did not reduce cell viability. HL60 cells were more resistant than PBMCs to the DNA damage induced by the different epoxides. With the exception of IO, the treatment for 24h resulted in an increase of DNA damage. FCS slightly protected PBMCs from the genotoxic effects induced by IO and BO, whilst no such effect was noted for the other compounds. Overall, the dose-dependent effects that were seen allowed us to define a genotoxicity scale for the different epoxides as follows: SO>EB>DEB>IO>PO>BO, which is in partial agreement with the International Agency for Research on Cancer (IARC) classification of the carcinogenic hazards.

  17. Genotoxic and histopathological biomarkers for assessing the effects of magnetic exfoliated vermiculite and exfoliated vermiculite in Danio rerio

    Energy Technology Data Exchange (ETDEWEB)

    Cáceres-Vélez, Paolin Rocio; Fascineli, Maria Luiza; Koppe Grisolia, Cesar [Department of Genetics and Morphology, Institute of Biological Sciences, Brasília University, Brasília (Brazil); Oliveira Lima, Emília Celma de [Chemistry Institute, Federal University of Goiás, Goiânia (Brazil); Sousa, Marcelo Henrique [Green Nanotechnology Group, Faculty of Ceilândia, Brasília University, Brasília (Brazil); Morais, Paulo César de [Physics Institute, Brasília University, Brasília (Brazil); Huazhong University of Science and Technology, School of Automation, Wuhan 430074 (China); Bentes de Azevedo, Ricardo, E-mail: razevedo@unb.br [Department of Genetics and Morphology, Institute of Biological Sciences, Brasília University, Brasília (Brazil)

    2016-05-01

    Magnetic exfoliated vermiculite is a synthetic nanocomposite that quickly and efficiently absorbs organic compounds such as oil from water bodies. It was developed primarily to mitigate pollution, but the possible adverse impacts of its application have not yet been evaluated. In this context, the acute toxicity of magnetic exfoliated vermiculite and exfoliated vermiculite was herein assessed by genotoxic and histopathological biomarkers in zebrafish (Danio rerio). DNA fragmentation was statistically significant for all groups exposed to the magnetic exfoliated vermiculite and for fish exposed to the highest concentration (200 mg/L) of exfoliated vermiculite, whereas the micronucleus frequency, nuclear abnormalities and histopathological alterations were not statistically significant for the fish exposed to these materials. In the intestinal lumen, epithelial cells and goblet cells, we found the presence of magnetic exfoliated vermiculite and exfoliated vermiculite, but no alterations or presence of the materials-test in the gills or liver were observed. Our findings suggest that the use of magnetic exfoliated vermiculite and exfoliated vermiculite during standard ecotoxicological assays caused DNA damage in D. rerio, whose alterations may be likely to be repaired, indicating that the magnetic nanoparticles have the ability to promote genotoxic damage, such as DNA fragmentation, but not mutagenic effects. - Highlights: • MEV is a synthetic nanocomposite that quickly and efficiently absorbs organic compounds such as oil from water bodies. • The use of MEV and EV during standard ecotoxicological assays caused DNA fragmentation in zebrafish. • The magnetic nanoparticles showed ability to promote genotoxic damage, but did not induce micronucleus in peripheral erythrocytes at 96 h of exposure. • The tested concentrations of MEV and EV do not cause significant histopathological alterations in the gills, liver and intestine of zebrafish.

  18. Genotoxicity and carcinogenicity risk of carbon nanotubes.

    Science.gov (United States)

    Toyokuni, Shinya

    2013-12-01

    Novel materials are often commercialized without a complete assessment of the risks they pose to human health because such assessments are costly and time-consuming; additionally, sometimes the methodology needed for such an assessment does not exist. Carbon nanotubes have the potential for widespread application in engineering, materials science and medicine. However, due to the needle-like shape and high durability of multiwalled carbon nanotubes (MWCNTs), concerns have been raised that they may induce asbestos-like pathogenicity when inhaled. Indeed, experiments in rodents supported this hypothesis. Notably, the genetic alterations in MWCNT-induced rat malignant mesothelioma were similar to those induced by asbestos. Single-walled CNTs (SWCNTs) cause mitotic disturbances in cultured cells, but thus far, there has been no report that SWCNTs are carcinogenic. This review summarizes the recent noteworthy publications on the genotoxicity and carcinogenicity of CNTs and explains the possible molecular mechanisms responsible for this carcinogenicity. The nanoscale size and needle-like rigid structure of CNTs appear to be associated with their pathogenicity in mammalian cells, where carbon atoms are major components in the backbone of many biomolecules. Publishing adverse events associated with novel materials is critically important for alerting people exposed to such materials. CNTs still have a bright future with superb economic and medical merits. However, appropriate regulation of the production, distribution and secondary manufacturing processes is required, at least to protect the workers.

  19. Polyvinyl polypyrrolidone attenuates genotoxicity of silver nanoparticles synthesized via green route, tested in Lathyrus sativus L. root bioassay.

    Science.gov (United States)

    Panda, Kamal K; Achary, V Mohan M; Phaomie, Ganngam; Sahu, Hrushi K; Parinandi, Narasimham L; Panda, Brahma B

    2016-08-01

    The silver nanoparticles (AgNPs) were synthesized extracellularly from silver nitrate (AgNO3) using kernel extract from ripe mango Mengifera indica L. under four different reaction conditions of the synthesis media such as the (i) absence of the reducing agent, trisodium citrate (AgNPI), (ii) presence of the reducing agent (AgNPII), (iii) presence of the cleansing agent, polyvinyl polypyrrolidone, PVPP (AgNPIII), and (iv) presence of the capping agent, polyvinyl pyrrolidone, PVP (AgNPIV). The synthesis of the AgNPs was monitored by UV-vis spectrophotometry. The AgNPs were characterised by the energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, and small-angle X-ray scattering. Functional groups on the AgNPs were established by the Fourier transform infrared spectroscopy. The AgNPs (AgNPI, AgNPII, AgNPIII and AgNPIV) were spherical in shape with the diameters and size distribution-widths of 14.0±5.4, 19.2±6.6, 18.8±6.6 and 44.6±13.2nm, respectively. Genotoxicity of the AgNPs at concentrations ranging from 1 to 100mgL(-1) was determined by the Lathyrus sativus L. root bioassay and several endpoint assays including the generation of reactive oxygen species and cell death, lipid peroxidation, mitotic index, chromosome aberrations (CA), micronucleus formation (MN), and DNA damage as determined by the Comet assay. The dose-dependent induction of genotoxicity of the silver ion (Ag(+)) and AgNPs was in the order Ag(+)>AgNPII>AgNPI>AgNPIV>AgNPIII that corresponded with their relative potencies of induction of DNA damage and oxidative stress. Furthermore, the findings underscored the CA and MN endpoint-based genotoxicity assay which demonstrated the genotoxicity of AgNPs at concentrations (≤10mgL(-1)) lower than that (≥10mgL(-1)) tested in the Comet assay. This study demonstrated the protective action of PVPP against the genotoxicity of AgNPIII which was independent of the size of the AgNPs in the L. sativus L. root bioassay

  20. Oxidative Stress Mechanisms Do Not Discriminate between Genotoxic and Nongenotoxic Liver Carcinogens.

    Science.gov (United States)

    Deferme, Lize; Wolters, Jarno; Claessen, Sandra; Briedé, Jacco; Kleinjans, Jos

    2015-08-17

    It is widely accepted that in chemical carcinogenesis different modes-of-action exist, e.g., genotoxic (GTX) versus nongenotoxic (NGTX) carcinogenesis. In this context, it has been suggested that oxidative stress response pathways are typical for NGTX carcinogenesis. To evaluate this, we examined oxidative stress-related changes in gene expression, cell cycle distribution, and (oxidative) DNA damage in human hepatoma cells (HepG2) exposed to GTX-, NGTX-, and noncarcinogens, at multiple time points (4-8-24-48-72 h). Two GTX (azathriopine (AZA) and furan) and two NGTX (tetradecanoyl-phorbol-acetate, (TPA) and tetrachloroethylene (TCE)) carcinogens as well as two noncarcinogens (diazinon (DZN, d-mannitol (Dman)) were selected, while per class one compound was deemed to induce oxidative stress and the other not. Oxidative stressors AZA, TPA, and DZN induced a 10-fold higher number of gene expression changes over time compared to those of furan, TCE, or Dman treatment. Genes commonly expressed among AZA, TPA, and DZN were specifically involved in oxidative stress, DNA damage, and immune responses. However, differences in gene expression between GTX and NGTX carcinogens did not correlate to oxidative stress or DNA damage but could instead be assigned to compound-specific characteristics. This conclusion was underlined by results from functional readouts on ROS formation and (oxidative) DNA damage. Therefore, oxidative stress may represent the underlying cause for increased risk of liver toxicity and even carcinogenesis; however, it does not discriminate between GTX and NGTX carcinogens.

  1. Ultrastructural Interactions and Genotoxicity Assay of Cerium Dioxide Nanoparticles on Mouse Oocytes

    Directory of Open Access Journals (Sweden)

    Blandine Courbiere

    2013-10-01

    Full Text Available Cerium dioxide nanoparticles (CeO2 ENPs are on the priority list of nanomaterials requiring evaluation. We performed in vitro assays on mature mouse oocytes incubated with CeO2 ENPs to study (1 physicochemical biotransformation of ENPs in culture medium; (2 ultrastructural interactions with follicular cells and oocytes using Transmission Electron Microscopy (TEM; (3 genotoxicity of CeO2 ENPs on follicular cells and oocytes using a comet assay. DNA damage was quantified as Olive Tail Moment. We show that ENPs aggregated, but their crystal structure remained stable in culture medium. TEM showed endocytosis of CeO2 ENP aggregates in follicular cells. In oocytes, CeO2 ENP aggregates were only observed around the zona pellucida (ZP. The comet assay revealed significant DNA damage in follicular cells. In oocytes, the comet assay showed a dose-related increase in DNA damage and a significant increase only at the highest concentrations. DNA damage decreased significantly both in follicular cells and in oocytes when an anti-oxidant agent was added in the culture medium. We hypothesise that at low concentrations of CeO2 ENPs oocytes could be protected against indirect oxidative stress due to a double defence system composed of follicular cells and ZP.

  2. genotoxicity of the pesticide dichlorvos and herbicide butachlor on rana zhenhaiensis tadpoles

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    genotoxicity of dichlorvos and butachlor on erythrocytes of rana zhenhaiensis tadpoles was investigated by the alkaline single-cell gel electrophoresis assay or comet assay.tadpoles were treated for 24 h in the laboratory with different concentrations of the testing agents,2.256,4.512,6.768,9.024,11.280 mg/l for dichlorvos and 0.292,0.584,0.876,1.168,1.460 mg/l for butachlor,to use the comet assay to test for the significance of dosage responsiveness to an increase in dna damage,as measured by the mean dna tail length-to-width ratio.the concentrations of 4.512 mg/l dichlorvos and 0.876 mg/l butachlor resulted in highly significant increases in dna damage of the tadpoles.there were linear correlations between the mean dna tail length-to-width ratio and the concentrations of the two test substances.our results showed that the two commonly used agricultural chemicals caused dose dependent dna damage of amphibians,and that comet assay might be a useful tool for measuring dna damage of tadpoles exposed in the field.

  3. Inhibition of TGFbeta1 Signaling Attenutates ATM Activity inResponse to Genotoxic Stress

    Energy Technology Data Exchange (ETDEWEB)

    Kirshner, Julia; Jobling, Michael F.; Pajares, Maria Jose; Ravani, Shraddha A.; Glick, Adam B.; Lavin, Martin J.; Koslov, Sergei; Shiloh, Yosef; Barcellos-Hoff, Mary Helen

    2006-09-15

    Ionizing radiation causes DNA damage that elicits a cellular program of damage control coordinated by the kinase activity of ataxia telangiectasia mutated protein (ATM). Transforming growth factor {beta}1 (TGF{beta}), which is activated by radiation, is a potent and pleiotropic mediator of physiological and pathological processes. Here we show that TGF{beta} inhibition impedes the canonical cellular DNA damage stress response. Irradiated Tgf{beta}1 null murine epithelial cells or human epithelial cells treated with a small molecule inhibitor of TGF{beta} type I receptor kinase exhibit decreased phosphorylation of Chk2, Rad17 and p53, reduced {gamma}H2AX radiation-induced foci, and increased radiosensitivity compared to TGF{beta} competent cells. We determined that loss of TGF{beta} signaling in epithelial cells truncated ATM autophosphorylation and significantly reduced its kinase activity, without affecting protein abundance. Addition of TGF{beta} restored functional ATM and downstream DNA damage responses. These data reveal a heretofore undetected critical link between the microenvironment and ATM that directs epithelial cell stress responses, cell fate and tissue integrity. Thus, TGF{beta}1, in addition to its role in homoeostatic growth control, plays a complex role in regulating responses to genotoxic stress, the failure of which would contribute to the development of cancer; conversely, inhibiting TGF{beta} may be used to advantage in cancer therapy.

  4. In vivo genotoxicity of furan in F344 rats at cancer bioassay doses

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Wei, E-mail: Wei.Ding@fda.hhs.gov [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Petibone, Dayton M. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Latendresse, John R. [Toxicologic Pathology Associates, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Pearce, Mason G. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Muskhelishvili, Levan; White, Gene A. [Toxicologic Pathology Associates, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Chang, Ching-Wei [Division of Personalized Nutrition and Medicine, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Mittelstaedt, Roberta A.; Shaddock, Joseph G.; McDaniel, Lea P. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Doerge, Daniel R. [Division of Biochemical Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States); Morris, Suzanne M.; Bishop, Michelle E.; Manjanatha, Mugimane G.; Aidoo, Anane; Heflich, Robert H. [Division of Genetic and Molecular Toxicology, US FDA/National Center for Toxicological Research, Jefferson, AR 72079 (United States)

    2012-06-01

    Furan, a potent rodent liver carcinogen, is found in many cooked food items and thus represents a human cancer risk. Mechanisms for furan carcinogenicity were investigated in male F344 rats using the in vivo Comet and micronucleus assays, combined with analysis of histopathological and gene expression changes. In addition, formamidopyrimidine DNA glycosylase (Fpg) and endonuclease III (EndoIII)-sensitive DNA damage was monitored as a measure of oxidative DNA damage. Rats were treated by gavage on four consecutive days with 2, 4, and 8 mg/kg bw furan, doses that were tumorigenic in 2-year cancer bioassays, and with two higher doses, 12 and 16 mg/kg. Rats were killed 3 h after the last dose, a time established as producing maximum levels of DNA damage in livers of furan-treated rats. Liver Comet assays indicated that both DNA strand breaks and oxidized purines and pyrimidines increased in a near-linear dose-responsive fashion, with statistically significant increases detected at cancer bioassay doses. No DNA damage was detected in bone marrow, a non-target tissue for cancer, and peripheral blood micronucleus assays were negative. Histopathological evaluation of liver from furan-exposed animals produced evidence of inflammation, single-cell necrosis, apoptosis, and cell proliferation. In addition, genes related to apoptosis, cell-cycle checkpoints, and DNA-repair were expressed at a slightly lower level in the furan-treated livers. Although a mixed mode of action involving direct DNA binding cannot be ruled out, the data suggest that furan induces cancer in rat livers mainly through a secondary genotoxic mechanism involving oxidative stress, accompanied by inflammation, cell proliferation, and toxicity. -- Highlights: ► Furan is a potent rodent liver carcinogen and represents a human cancer risk. ► Furan induces DNA damage in rat liver at cancer bioassay doses. ► Furan induces oxidative stress, inflammation and cell proliferation in rat liver. ► Expression of

  5. Subchronic mycotoxicoses in Wistar rats: assessment of the in vivo and in vitro genotoxicity induced by fumonisins and aflatoxin B(1), and oxidative stress biomarkers status.

    Science.gov (United States)

    Theumer, M G; Cánepa, M C; López, A G; Mary, V S; Dambolena, J S; Rubinstein, H R

    2010-01-31

    Some evidence suggests that fumonisin B(1) (FB(1)), a worldwide toxic contaminant of grains produced by Fusarium verticillioides, exhibits an oxidative stress mediated genotoxicity. We studied the DNA damage (by the alkaline comet and the micronucleus tests) and biomarkers of cellular oxidative stress (malondialdehyde, MDA; catalase, CAT; and superoxide dismutase, SOD) in spleen mononuclear cells of male Wistar rats subchronically (90 days) fed on a control experimental diet (CED) or poisoned with experimental diets contaminated with a culture material containing 100 ppm of FB(1) (FED), with 40 ppb of aflatoxin B(1) (a common toxic co-contaminant in cereals, AFB(1)ED), and with a mixture of both toxins (MED). The DNA damage was found in 13.7%, 81.7%, 98.0% and 99.3% (comet assay) and in 2.8%, 7.0%, 10.8% and 8.8% (micronucleus technique) in groups CED, FED, AFB(1)ED and MED, respectively. The MDA levels as well as the CAT and SOD activities were increased in all the poisoned animals. A similar behavior was observed in cells exposed in vitro to the toxins. These data support the hypothesis of an oxidative stress mediated genotoxicity induced by FB(1). Furthermore, the extent of DNA damage assessed by the comet assay suggests a possible protective effect of the fumonisins-AFB(1) mixtures in vitro against the genotoxicity induced individually by the toxins.

  6. Determination of genotoxic effects of Imazethapyr herbicide in Allium cepa root cells by mitotic activity, chromosome aberration, and comet assay.

    Science.gov (United States)

    Liman, Recep; Ciğerci, İbrahim Hakkı; Öztürk, Nur Serap

    2015-02-01

    Imazethapyr (IM) is an imidazolinone herbicide that is currently used for broad-spectrum weed control in soybean and other legume crops. In this study, cytotoxic and genotoxic effects of IM were investigated by using mitotic index (MI), mitotic phases, chromosomal abnormalities (CAs) and DNA damage on the root meristem cells of Allium cepa. In Allium root growth inhibition test, EC50 value was determined as 20 ppm, and 0.5xEC50, EC50 and 2xEC50 concentrations of IM herbicide were introduced to onion tuber roots. Distilled water and methyl methane sulfonate (MMS, 10 mg/L) were used as a negative and positive control, respectively. As A. cepa cell cycle is 24 hours, so, application process was carried out for 24, 48, 72 and 96 hours. All the applied doses decreased MIs compared to control group and these declines were found to be statistically meaningful. Analysis of the chromosomes showed that 10 ppm IM except for 48 h induced CAs but 40 ppm IM except for 72 h decreased CAs. DNA damage was found significantly higher in 20 and 40 ppm of IM compared to the control in comet assay. These results indicated that IM herbicide exhibits cytotoxic activity but not genotoxic activity (except 10 ppm) and induced DNA damage in a dose dependent manner in A. cepa root meristematic cells.

  7. In vitro ZnCl2 cytotoxicity and genotoxicity in human leukocytes: Zero-order kinetic cellular zinc influx

    Directory of Open Access Journals (Sweden)

    Luciana Pereira de Pereira

    2015-06-01

    Full Text Available Zinc (Zn is an essential trace element for cellular viability, but concentrations above physiologic level may lead to cellular damage. The purpose of the present study was to evaluate the in vitro ZnCl2 genotoxicity and cytotoxicity in human leukocyte cells. This was assessed in an unprecedented way that correlated the level of intracellular Zn after cell exposition with the cellular damage. The exposure to increased Zn concentrations (2.5-20 µg mL-1, showed significantly reduced cellular leukocyte viability. However, significant DNA damages were observed only when the Zn exposure concentrations were from 10-20 µg mL-1. The Zn intracellular levels found in leukocytes was from 72.25-268.9 ρg cell-1, starting to induce cytotoxicity and genotoxicity at concentrations of 95.68 and 126.2 ρg cell-1, respectively. The relationship between the exposure concentration and intracellular levels of Zn suggests that the influx of Zn, in the form of ZnCl2, occurs in human leukocytes under zero-order kinetics.

  8. Red mud a byproduct of aluminum production contains soluble vanadium that causes genotoxic and cytotoxic effects in higher plants

    Energy Technology Data Exchange (ETDEWEB)

    Mišík, Miroslav [Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna (Austria); Burke, Ian T. [Earth Surface Science Institute, School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Reismüller, Matthias; Pichler, Clemens; Rainer, Bernhard [Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna (Austria); Mišíková, Katarina [Department of Botany, Faculty of Natural Sciences, Comenius University, Bratislava (Slovakia); Mayes, William M. [Centre for Environmental and Marine Sciences, University of Hull, Scarborough YO11 3AZ (United Kingdom); Knasmueller, Siegfried, E-mail: siegfried.knasmueller@meduniwien.ac.at [Institute of Cancer Research, Department of Medicine I, Comprehensive Cancer Center, Medical University of Vienna, Vienna (Austria)

    2014-09-15

    Red mud (RM) is a byproduct of aluminum production; worldwide between 70 and 120 million tons is produced annually. We analyzed RM which was released in the course of the Kolontar disaster in Hungary into the environment in acute and genotoxicity experiments with plants which are widely used for environmental monitoring. We detected induction of micronuclei which reflect chromosomal damage in tetrads of Tradescantia and in root cells of Allium as well as retardation of root growth with contaminated soils and leachates. Chemical analyses showed that RM contains metals, in particular high concentrations of vanadium. Follow-up experiments indicated that vanadate causes the effects in the plants. This compound causes also in humans DNA damage and positive results were obtained in carcinogenicity studies. Since it was found also in RM from other production sites our findings indicate that its release in the environment is a global problem which should be studied in more detail. Capsule abstract: Our findings indicate that the red mud causes genotoxic effect in plants probably due to the presence of vanadate which is contained at high concentrations in the residue. - Highlights: • Red mud, a by-product of aluminum production, causes DNA-damage in higher plants. • We showed that this effect is caused by vanadate a known carcinogenic genotoxin. • Vanadate is contained in high concentrations in the residue. • Release of red mud may cause adverse effects in ecosystems and affect human health.

  9. Genotoxicity of cadmium chloride in the marine gastropod Nerita chamaeleon using comet assay and alkaline unwinding assay.

    Science.gov (United States)

    Sarkar, Anupam; Bhagat, Jacky; Ingole, Baban S; Rao, Durga P; Markad, Vijaykumar L

    2015-02-01

    This paper presents an evaluation of the genotoxic effects of cadmium chloride (CdCl2 ) on marine gastropod, Nerita chamaeleon following the technique of comet assay and the DNA alkaline unwinding assay (DAUA). In this study, the extent of DNA damage in gill cells of N. chamaeleon was measured after in vivo exposure to four different concentrations (10, 25, 50, and 75 µg/L) of CdCl2 . In vitro exposure of hydrogen peroxide (H2 O2 ; 1, 10, 25, and 50 µM) of the gill cells showed a significant increase in the percentage tail DNA, Olive tail moment, and tail length (TL). Significant changes in percentage tail DNA by CdCl2 exposure were observed in all exposed groups of snails with respect to those in control. Exposure to 75 µg/L of CdCl2 produced significant decrease in DNA integrity as measured by DAUA at all duration with respect to control. In vivo exposure to different concentrations of CdCl2 (10, 25, 50, and 75 µg/L) to N. chamaeleon showed considerable increase in DNA damage as observed by both alkaline comet assay and the DAUA. The extent of DNA damage in marine gastropods determined by the application of alkaline comet assay and DAUA clearly indicated the genotoxic responses of marine gastropod, N. chamaeleon to a wide range of cadmium concentration in the marine environment.

  10. Preliminary study of genotoxicity evaluation of orthodontic miniscrews on mucosa oral cells by the alkaline comet assay.

    Science.gov (United States)

    Martín-Cameán, Ana; Puerto, María; Jos, Ángeles; Azqueta, Amaya; Iglesias-Linares, Alejandro; Solano, Enrique; Cameán, Ana M

    2015-01-01

    Miniscrew implants are widely used nowadays in orthodontic treatments due to their good results in clinical practice. However, data regarding the biocompatibility of commercially available orthodontic miniscrews and temporary devices are very scarce, and their role as genotoxicity inducers has been not previously evaluated with the alkaline comet assay. The aim of this study was to investigate the DNA damage in buccal cells of patients subjected to orthodontic treatments. The alkaline comet assay has been applied in oral mucosa cells from patients treated with conventional orthodontic treatment in comparison to patients treated additionally with miniscrews, non-treated volunteers (control) and smoking volunteers (positive control). The application of orthodontic appliances and miniscrews induced significant and similar (2-fold) increases of %DNA in tail in comparison to control group. Females experienced a significant increase in %DNA in all the treatments in comparison to the control group, whereas males showed significant damage only with the combined orthodontic and miniscrew treatment. In conclusion, conventional orthodontic appliances induced genotoxicity, and the incorporation of miniscrews assayed did not imply any additional increase of DNA damage.

  11. Analysis of Delphinidin and Luteolin Genotoxicity in Human Lymphocyte Culture

    Directory of Open Access Journals (Sweden)

    Jasmin Ezić

    2015-08-01

    Full Text Available Introduction: Bioflavonoids delphinidin (2-(3,4,5-Trihydroxyphenylchromenylium-3,5,7-triol and luteolin (2-(3,4-Dihydroxyphenyl-5,7-dihydroxy-4-chromenone have been recognized as promising antioxidants and anticancer substances. Due to their extensive use, the goal of the research was to determine whether they have any genotoxic potential in vitro.Methods: Analysis of genotoxic potential was performed applying chromosome aberrations test in human lymphocyte culture, as this kind of research was not conducted abundantly for these two bioflavonoids. Delphinidin and luteolin were dissolved in DMSO and added to cultures in final concentrations of 25, 50 and 100 μM.Results: In human lymphocytes cultures Delphinidin induced PCDs in all treatments, potentially affecting the cell cycle and topoisomerase II activity. In concentration of 50 μM luteolin showed strong genotoxic effects and caused significant reduction of cell proliferation.Conclusion: Luteolin exhibited certain genotoxic and cytostatic potential. Delphinidin was not considered genotoxic, however its impact on mitosis, especially topoisomerase II activity, was revealed.

  12. Genotoxic risk in rubber manufacturing industry: a systematic review.

    Science.gov (United States)

    Bolognesi, Claudia; Moretto, Angelo

    2014-10-15

    A large body of evidence from epidemiological studies among workers employed in the rubber manufacturing industry has indicated a significant excess cancer risk in a variety of sites. The International Agency for Research on Cancer has recently classified the "Occupational exposures in the rubber-manufacturing industry" as carcinogenic to humans (Group 1). A genotoxic mechanism for the increased cancer risk was suggested on the basis of the evidence from the scientific literature. Exposure assessment studies have shown that workers in the rubber manufacturing industry may be exposed to different airborne carcinogenic and/or genotoxic chemicals, such as certain aromatic amines, polycyclic aromatic hydrocarbons, N-nitrosamines, although the available information does not allow to establish a causal association of cancer or genotoxic risk with particular substances/classes of chemicals or specific jobs. The aim of this paper is to critically evaluate, by conducting a systematic review, the available biomonitoring studies using genotoxicity biomarkers in rubber manufacturing industry. This systematic review suggests that a genotoxic hazard may still be present in certain rubber manufacturing industries. A quantitative risk assessment needs further studies addressing the different, processes and chemicals in the rubber manufacturing industries.

  13. Evaluation of genotoxicity testing of FDA approved large molecule therapeutics.

    Science.gov (United States)

    Sawant, Satin G; Fielden, Mark R; Black, Kurt A

    2014-10-01

    Large molecule therapeutics (MW>1000daltons) are not expected to enter the cell and thus have reduced potential to interact directly with DNA or related physiological processes. Genotoxicity studies are therefore not relevant and typically not required for large molecule therapeutic candidates. Regulatory guidance supports this approach; however there are examples of marketed large molecule therapeutics where sponsors have conducted genotoxicity studies. A retrospective analysis was performed on genotoxicity studies of United States FDA approved large molecule therapeutics since 1998 identified through the Drugs@FDA website. This information was used to provide a data-driven rationale for genotoxicity evaluations of large molecule therapeutics. Fifty-three of the 99 therapeutics identified were tested for genotoxic potential. None of the therapeutics tested showed a positive outcome in any study except the peptide glucagon (GlucaGen®) showing equivocal in vitro results, as stated in the product labeling. Scientific rationale and data from this review indicate that testing of a majority of large molecule modalities do not add value to risk assessment and support current regulatory guidance. Similarly, the data do not support testing of peptides containing only natural amino acids. Peptides containing non-natural amino acids and small molecules in conjugated products may need to be tested.

  14. Differential resistance of human embryonic stem cells and somatic cell types to hydrogen peroxide-induced genotoxicity may be dependent on innate basal intracellular ROS levels.

    Science.gov (United States)

    Vinoth, Kumar Jayaseelan; Manikandan, Jayapal; Sethu, Swaminathan; Balakrishnan, Lakshmidevi; Heng, Alexis; Lu, Kai; Poonepalli, Anuradha; Hande, Manoor Prakash; Cao, Tong

    2015-01-01

    Previously, we demonstrated that undifferentiated human embryonic stem cells (hESC) displayed higher resistance to oxidative and genotoxic stress compared to somatic cells, but did not further probe the underlying mechanisms. Using H₂O₂-induced genotoxicity as a model, this study investigated whether higher resistance of hESC to oxidative and genotoxic stress could be due to lower innate basal intracellular levels of reactive oxygen species (ROS), as compared to their differentiated fibroblastic progenies (H1F) and two other somatic cell types - human embryonic palatal mesenchymal (HEPM) cells and peripheral blood lymphocytes (PBL). Comet assay demonstrated that undifferentiated hESC consistently sustained lower levels of DNA damage upon acute exposure to H₂O₂ for 30 min, compared to somatic cells. DCFDA and HE staining with flow cytometry showed that undifferentiated hESC had lower innate basal intracellular levels of reactive oxygen species compared to somatic cells, which could lead to their higher resistance to genotoxic stress upon acute exposure to H₂O₂.

  15. Genetic Damage Induced by Accidental Environmental Pollutants

    Directory of Open Access Journals (Sweden)

    Beatriz Pérez-Cadahía

    2006-01-01

    Full Text Available Petroleum is one of the main energy sources worldwide. Its transport is performed by big tankers following some established marine routes. In the last 50 years a total amount of 37 oil tankers have given rise to great spills in different parts of the world, Prestige being the last one. After the accident, a big human mobilisation took place in order to clean beaches, rocks and fauna, trying to reduce the environmental consequences of this serious catastrophe. These people were exposed to the complex mixture of compounds contained in the oil. This study aimed at determine the level of environmental exposure to volatile organic compounds (VOC, and the possible damage induced on the population involved in the different cleaning tasks by applying the genotoxicity tests sister chromatid exchanges (SCE, micronucleus (MN test, and comet assay. Four groups of individuals were included: volunteers (V, hired manual workers (MW, hired high-pressure cleaner workers (HPW and controls. The higher VOC levels were associated with V environment, followed by MW and lastly by HPW, probably due to the use of high-pressure cleaners. Oil exposure during the cleaning tasks has caused an increase in the genotoxic damage in individuals, the comet assay being the most sensitive biomarker to detect it. Sex, age and tobacco consumption have shown to influence the level of genetic damage, while the effect of using protective devices was less noticeable than expected, perhaps because the kind used was not the most adequate.

  16. H2 O2-induced higher order chromatin degradation: A novel mechanism of oxidative genotoxicity

    Indian Academy of Sciences (India)

    Gregory W Konat

    2003-02-01

    The genotoxicity of reactive oxygen species (ROS) is well established. The underlying mechanism involves oxidation of DNA by ROS. However, we have recently shown that hydrogen peroxide (H2O2), the major mediator of oxidative stress, can also cause genomic damage indirectly. Thus, H2O2 at pathologically relevant concentrations rapidly induces higher order chromatin degradation (HOCD), i.e. enzymatic excision of chromatin loops and their oligomers at matrix-attachment regions. The activation of endonuclease that catalyzes HOCD is a signalling event triggered specifically by H2O2. The activation is not mediated by an influx of calcium ions, but resting concentrations of intracellular calcium ions are required for the maintenance of the endonuclease in an active form. Although H2O2-induced HOCD can efficiently dismantle the genome leading to cell death, under sublethal oxidative stress conditions H2O2-induced HOCD may be the major source of somatic mutations.

  17. Genotoxicity of processed food items and ready-to-eat snacks in Finland.

    Science.gov (United States)

    Omoruyi, Iyekhoetin Matthew; Pohjanvirta, Raimo

    2014-11-01

    Processed foods are an insufficiently characterized source of chemical mutagens for consumers. Here, we evaluated the genotoxicity of selected food products in Finland. Mutagenicity was determined by the standard plate incorporation assay followed by methylcellulose overlay and treat-and-wash assays, using the Salmonella strains TA 100 and 98 with and without metabolic activation. Generally, the mutagenic activity of food samples was low, but exhibited lot-wise variation. Cold cuts of cold-smoked beef, grilled turkey, and smoked chicken (a single batch of each) were mutagenic in all three assays with the TA 100 strain with and without metabolic activation, indicating the mutagenic effect was not secondary to histidine release from the food products. However, none of the food extracts showing mutagenic potential induced DNA damage in vitro using the Comet Assay. Our findings imply that in Finland today, there are still products the production methods of which should be refined to reduce the potential risk of mutagenicity to consumers.

  18. Disperse Red 1 (textile dye) induces cytotoxic and genotoxic effects in mouse germ cells.

    Science.gov (United States)

    Fernandes, Fábio Henrique; Bustos-Obregon, Eduardo; Salvadori, Daisy Maria Fávero

    2015-06-01

    Disperse Red 1 (DR1), which is widely used in the textile industry, is an azo dye that contributes to the toxicity and pollution of wastewater. To assess the toxic effects of DR1 on reproduction, sexually mature male mice (Mus musculus, strain CF-1) were orally (gavage) treated with single doses of the compound at 20, 100 and 500 mg/kg body weight. Testicular features and sperm parameters were evaluated 8.3, 16.6 and 24.9 days after treatments. In addition to testicular toxicity caused by the dye, the data clearly showed an increased frequency of sperm with abnormal morphology and decreased fertility. An increased amount of DNA damage was also detected in testis cells 16.6 and 24.9 days after treatments with 100 and 500 mg/kg. This study demonstrated the toxic and genotoxic effects of DR1, indicating the harmful activity of this dye on reproductive health.

  19. Comparison of cytotoxicity and genotoxicity induced by the extracts of methanol and gasoline engine exhausts.

    Science.gov (United States)

    Zhang, Zunzhen; Che, Wangjun; Liang, Ying; Wu, Mei; Li, Na; Shu, Ya; Liu, Fang; Wu, Desheng

    2007-09-01

    Gasoline engine exhaust has been considered a major source of air pollution in China, and methanol is considered as a potential substitute for gasoline fuel. In this study, the genotoxicity and cytotoxicity of organic extracts of condensate, particulate matters (PM) and semivolatile organic compounds (SVOC) of gasoline and absolute methanol engine exhaust were examined by using MTT assay, micronucleus assay, comet assay and Ames test. The results have showed that gasoline engine exhaust exhibited stronger cytotoxicity to human lung carcinoma cell lines (A549 cell) than methanol engine exhaust. Furthermore, gasoline engine exhaust increased micronucleus formation, induced DNA damage in A549 cells and increased TA98 revertants in the presence of metabolic activating enzymes in a concentration-dependent manner. In contrast, methanol engine exhaust failed to exhibit these adverse effects. The results suggest methanol may be used as a cleaner fuel for automobile.

  20. Genotoxicity test of self-renovated ceramics in primary human peripheral lymphocytes.

    Science.gov (United States)

    Hua, Nan; Zhu, Huifang; Zhuang, Jing; Chen, Liping

    2014-12-01

    Zirconia-based ceramics is widely used in dentistry. Different compositions of ceramics have different features. Our self-renovated ceramics become more machinable without scarifying its dental restoration properties after adjusting ratio of lanthanum phosphate (LaPO4)/yttrium oxide (Y2O3). In order to evaluate its safety, here, we tested its genotoxicity in primary human peripheral lymphocytes. The human lymphocytes cultured on three groups of different ratios of LaPO4/Y2O3 diphase ceramics for 6 days showed little effect of growth inhibition and similar effect of growth trend to the negative control. Furthermore, single-cell gel electrophoresis (comet assay) indicated that there was no significant difference of the value of tail moment between the tested ceramics and negative control, the IPS Empress II (P > 0.05). Our findings implicate that our self-renovated ceramics do not induce DNA damages in human peripheral lymphocytes and support their future clinic application.

  1. Nucleo-cytoplasmic communication in apoptotic response to genotoxic and inflammatory stress

    Institute of Scientific and Technical Information of China (English)

    Jean Y. J. WANG

    2005-01-01

    Genotoxic agents or inflammatory cytokines activate cellular stress responses and trigger programmed cell death.We have identified a signal transduction module, including three nuclear proteins that participate in the regulation of cell death induced by chemotherapeutic agents and tumor necrosis factor (TNF). In this nuclear signaling module, retinoblastoma protein (Rb) functions as an inhibitor of apoptotic signal transduction. Inactivation of Rb by phosphorylation or caspase-dependent cleavage/degradation is required for cell death to occur. Rb inhibits the Abl tyrosine kinase. Thus,Rb inactivation is a pre-requisite for Abl activation by DNA damage or TNF. Activation of nuclear Abl and its downstream effector p73 induces mitochondriadependent cell death. The involvement of these nuclear signal transducers in TNF induced apoptosis, which does not require new gene expression, indicates that nuclear events other than transcription can contribute to extrinsic apoptotic signal transduction.

  2. Mutagenic and genotoxic activities of four pesticides: captan, foltaf, phosphamidon and furadan.

    Science.gov (United States)

    Saxena, S; Ashok, B T; Musarrat, J

    1997-05-01

    The mutagenic and genotoxic potential of four pesticides viz. captan, foltaf, phosphamidon and furadan was evaluated by the Ames mutagenicity assay and their DNA damaging ability on radiation repair defective E. coli K-12 strains respectively. The mutagenic spectrum revealed captan to be most mutagenic in the absence of metabolic activation, while the presence of S9 mix led to an attenuated mutagenic response. Foltaf, phosphamidon and furadan were detected as relatively weaker mutagens. A significant decrease in the survival of SOS defective mutants, recA, lexA and pol- of E. coli was observed as compared to their wild-type counterparts in the presence of the pesticides. The role of SOS repair genes gains further support from the Salmonella strains triggering the error-prone SOS response.

  3. Human mesenchymal stem cells are resistant to cytotoxic and genotoxic effects of cisplatin in vitro

    Directory of Open Access Journals (Sweden)

    Bruno Corrêa Bellagamba

    2016-03-01

    Full Text Available Abstract Mesenchymal stem cells (MSCs are known for their important properties involving multilineage differentiation potential., trophic factor secretion and localization along various organs and tissues. On the dark side, MSCs play a distinguished role in tumor microenvironments by differentiating into tumor-associated fibroblasts or supporting tumor growth via distinct mechanisms. Cisplatin (CIS is a drug widely applied in the treatment of a large number of cancers and is known for its cytotoxic and genotoxic effects, both in vitro and in vivo. Here we assessed the effects of CIS on MSCs and the ovarian cancer cell line OVCAR-3, by MTT and comet assays. Our results demonstrated the resistance of MSCs to cell death and DNA damage induction by CIS, which was not observed when OVCAR-3 cells were exposed to this drug.

  4. Mutagenicity and genotoxicity in gill erythrocyte cells of Poecilia reticulata exposed to a glyphosate formulation.

    Science.gov (United States)

    De Souza Filho, José; Sousa, Caio César Neves; Da Silva, Cláudio Carlos; De Sabóia-Morais, Simone Maria Teixeira; Grisolia, Cesar Koppe

    2013-11-01

    Poecilia reticulata were exposed to herbicide Roundup Transorb(®) for micronucleus test, nuclear abnormalities and comet assay. The exposure-concentrations were based on CL50-96 h following 0, 1.41, 2.83, 4.24 and 5.65 μL L(-1) for 24 h. Micronucleus and comets were significantly increased in the gill erythrocyte cells after herbicide exposure compared with the non-exposed group. Results showed a gradual increase in the number of damaged cells, indicating a concentration-dependent effect and that this herbicide was mutagenic and genotoxic to P. reticulata and this effect could be attributed to a combination of compounds contained in the formulation with the active ingredient glyphosate.

  5. Genotoxicity of unmodified and organo-modified montmorillonite

    DEFF Research Database (Denmark)

    Sharma, Anoop Kumar; Schmidt, Bjørn; Frandsen, Henrik Lauritz;

    2010-01-01

    The natural clay mineral montmorillonite (Cloisite (R) Na+) and an organo-modified montmorillonite (Cloisite (R) 30B) were investigated for genotoxic potential as crude suspensions and as suspensions filtrated through a 0.2-mu m pore-size filter to remove particles above the nanometre range...... absent in the filtered samples, which was independently confirmed by dynamic light-scattering measurements. Detection and identification of free quaternary ammonium modifier in the filtered sample was carried out by HPLC-Q-TOF/MS and revealed a total concentration of a mixture of quaternary ammonium...... analogues of 1.57 mu g/ml. These findings suggest that the genotoxicity of organo-modified montmorillonite was caused by the organo-modifier. The detected organo-modifier mixture was synthesized and comet-assay results showed that the genotoxic potency of this synthesized organo-modifier was in the same...

  6. Genotoxicity of Superparamagnetic Iron Oxide Nanoparticles in Granulosa Cells

    Directory of Open Access Journals (Sweden)

    Marina Pöttler

    2015-11-01

    Full Text Available Nanoparticles that are aimed at targeting cancer cells, but sparing healthy tissue provide an attractive platform of implementation for hyperthermia or as carriers of chemotherapeutics. According to the literature, diverse effects of nanoparticles relating to mammalian reproductive tissue are described. To address the impact of nanoparticles on cyto- and genotoxicity concerning the reproductive system, we examined the effect of superparamagnetic iron oxide nanoparticles (SPIONs on granulosa cells, which are very important for ovarian function and female fertility. Human granulosa cells (HLG-5 were treated with SPIONs, either coated with lauric acid (SEONLA only, or additionally with a protein corona of bovine serum albumin (BSA; SEONLA-BSA, or with dextran (SEONDEX. Both micronuclei testing and the detection of γH2A.X revealed no genotoxic effects of SEONLA-BSA, SEONDEX or SEONLA. Thus, it was demonstrated that different coatings of SPIONs improve biocompatibility, especially in terms of genotoxicity towards cells of the reproductive system.

  7. DNA Damage Response and Immune Defence: Links and Mechanisms

    Directory of Open Access Journals (Sweden)

    Björn Schumacher

    2016-08-01

    Full Text Available DNA damage plays a causal role in numerous human pathologies including cancer, premature aging and chronic inflammatory conditions. In response to genotoxic insults, the DNA damage response (DDR orchestrates DNA damage checkpoint activation and facilitates the removal of DNA lesions. The DDR can also arouse the immune system by for example inducing the expression of antimicrobial peptides as well as ligands for receptors found on immune cells. The activation of immune signalling is triggered by different components of the DDR including DNA damage sensors, transducer kinases, and effectors. In this review, we describe recent advances on the understanding of the role of DDR in activating immune signalling. We highlight evidence gained into (i which molecular and cellular pathways of DDR activate immune signalling, (ii how DNA damage drives chronic inflammation, and (iii how chronic inflammation causes DNA damage and pathology in humans.

  8. Does uranium exposure induce oxidative stress and genotoxicity in the teleostean Danio rerio? first experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, S.; Devaux, A.; Simon, O.; Buet, A.; Pradines, C. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Within the Envirhom research program, key advances have been obtained in uranium bioaccumulation and underlying mechanisms understanding in various biological models at the individual level. However, considering different scales of biological effects (from early to delayed ones, from low to high level of organization) is crucial to provide ecologically relevant indicators. Organisms counteract stress induced by pollutant exposure through a wide range of physiological responses being both dose and time dependent. Effects at higher hierarchical levels are always preceded by early changes in biological processes, from subtle biochemical disturbances to impaired physiological functions, increased susceptibility to other stresses, reduced life-span Within this global context, preliminary experiments were carried out on adult zebra fish (Danio rerio), to assess early changes after short-term uranium exposure. Among the subsequent primary subcellular damages oxidative stress and genotoxicity (characterizing both chemo-toxicity and radiotoxicity) are relevant endpoints, thus requiring the knowledge of dose-effects relationships as a first operational approach to provide useful tool in predicting possible effects of U exposure. Zebra fish has been selected due to its small size (facilitating its maintenance) and its extended use in eco-toxicological studies. Moreover, its short life-cycle will allow to carry out chronic exposure experiments (along the whole life-cycle). Four uranium concentrations (0, 20, 100 and 500{mu}g.L{sup -1}) and five sampling times (0, 0.5, 1, 5 and 10 days) were selected. Catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were measured as oxidative stress bio-markers. DNA damage level was assessed in zebra fish erythrocytes using the comet assay. Uranium bioaccumulation was concurrently studied to understand observed bio-marker responses. Further experiments, dedicated to the assessment of the impact of chronic uranium

  9. Genotoxic Effects in Swimmers Exposed to Disinfection By-products in Indoor Swimming Pools

    Science.gov (United States)

    Kogevinas, Manolis; Villanueva, Cristina M.; Font-Ribera, Laia; Liviac, Danae; Bustamante, Mariona; Espinoza, Felicidad; Nieuwenhuijsen, Mark J.; Espinosa, Aina; Fernandez, Pilar; DeMarini, David M.; Grimalt, Joan O.; Grummt, Tamara; Marcos, Ricard

    2010-01-01

    Background Exposure to disinfection by-products (DBPs) in drinking water has been associated with cancer risk. A recent study (Villanueva et al. 2007; Am J Epidemiol 165:148–156) found an increased bladder cancer risk among subjects attending swimming pools relative to those not attending. Objectives We evaluated adults who swam in chlorinated pools to determine whether exposure to DBPs in pool water is associated with biomarkers of genotoxicity. Methods We collected blood, urine, and exhaled air samples from 49 nonsmoking adult volunteers before and after they swam for 40 min in an indoor chlorinated pool. We estimated associations between the concentrations of four trihalomethanes (THMs) in exhaled breath and changes in micronuclei (MN) and DNA damage (comet assay) in peripheral blood lymphocytes before and 1 hr after swimming; urine mutagenicity (Ames assay) before and 2 hr after swimming; and MN in exfoliated urothelial cells before and 2 weeks after swimming. We also estimated associations and interactions with polymorphisms in genes related to DNA repair or to DBP metabolism. Results After swimming, the total concentration of the four THMs in exhaled breath was seven times higher than before swimming. The change in the frequency of micronucleated lymphocytes after swimming increased in association with higher exhaled concentrations of the brominated THMs (p = 0.03 for bromodichloromethane, p = 0.05 for chlorodibromomethane, p = 0.01 for bromoform) but not chloroform. Swimming was not associated with DNA damage detectable by the comet assay. Urine mutagenicity increased significantly after swimming, in association with the higher concentration of exhaled bromoform (p = 0.004). We found no significant associations with changes in micronucleated urothelial cells. Conclusions Our findings support potential genotoxic effects of exposure to DBPs from swimming pools. The positive health effects gained by swimming could be increased by reducing the potential health

  10. Genotoxicity evaluation of titanium dioxide nanoparticles using the Ames test and Comet assay.

    Science.gov (United States)

    Woodruff, Robert S; Li, Yan; Yan, Jian; Bishop, Michelle; Jones, M Yvonne; Watanabe, Fumiya; Biris, Alexandru S; Rice, Penelope; Zhou, Tong; Chen, Tao

    2012-11-01

    Titanium dioxide nanoparticles (TiO2-NPs) are being used increasingly for various industrial and consumer products, including cosmetics and sunscreens because of their photoactive properties. Therefore, the toxicity of TiO2-NPs needs to be thoroughly understood. In the present study, the genotoxicity of 10nm uncoated sphere TiO2-NPs with an anatase crystalline structure, which has been well characterized in a previous study, was assessed using the Salmonella reverse mutation assay (Ames test) and the single-cell gel electrophoresis (Comet) assay. For the Ames test, Salmonella strains TA102, TA100, TA1537, TA98 and TA1535 were preincubated with eight different concentrations of the TiO2-NPs for 4 h at 37 °C, ranging from 0 to 4915.2 µg per plate. No mutation induction was found. Analyses with transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) showed that the TiO2-NPs were not able to enter the bacterial cell. For the Comet assay, TK6 cells were treated with 0-200 µg ml(-1) TiO2-NPs for 24 h at 37 °C to detect DNA damage. Although the TK6 cells did take up TiO2-NPs, no significant induction of DNA breakage or oxidative DNA damage was observed in the treated cells using the standard alkaline Comet assay and the endonuclease III (EndoIII) and human 8-hydroxyguanine DNA-glycosylase (hOGG1)-modified Comet assay, respectively. These results suggest that TiO2-NPs are not genotoxic under the conditions of the Ames test and Comet assay.

  11. Investigations of potential susceptibility toward formaldehyde-induced genotoxicity.

    Science.gov (United States)

    Zeller, Jasmin; Högel, Josef; Linsenmeyer, Regina; Teller, Christopher; Speit, Günter

    2012-09-01

    Blood samples were taken from three groups of volunteers (30 male smokers, 30 female non-smokers, and 30 school children) and tested for ex vivo susceptibility toward formaldehyde (FA)-induced genotoxicity. Blood samples were exposed to 150 μM FA for 2 h, and the induction of DNA-protein crosslinks (DPX) in leukocytes was measured by a modification of the alkaline comet assay (i.e., reduction of γ-irradiation induced DNA migration). Removal of DPX was determined by the abolition of FA-induced reduction in DNA migration within 4 h after the end of the exposure. Induction and persistence of FA-induced DNA lesions was also measured by the sister chromatid exchange (SCE) test with cultured lymphocytes after treatment of whole blood cultures with FA (150 μM). Furthermore, the expression (mRNA level) of the GSH-dependent formaldehyde dehydrogenase (FDH, identical to alcohol dehydrogenase 5; ADH5) was measured in leukocytes by quantitative real-time RT-PCR with TaqMan probes. The subjects were also analyzed for the GSTM1 and GSTT1 metabolic gene polymorphisms and a correlation analysis with the investigated genetic endpoints for FA-induced genotoxicity was performed. The results indicate that there are no biologically relevant differences between the three study groups with regard to the various indicators of cellular sensitivity toward FA-induced genotoxic effects and the expression of FDH. The induced genotoxic effects were not associated with polymorphisms in GSTM1 and GSTT1. None of the study groups showed particular mutagen sensitivity toward FA-induced genotoxicity. These results suggest that a low scaling factor to address possible human inter-individual differences in FA-induced genotoxicity could be reasonable.

  12. Evaluation of the genotoxic and mutagenic potentials of homeopathic Candida albicans solutions

    Directory of Open Access Journals (Sweden)

    André Luis Santos

    2011-09-01

    Full Text Available Background: Candida spp is naturally found in humans’ flora of skin, gastrointestinal and genitourinary tracts and, in general, up to 75% of the population does not have any symptom [1]. However, oral candidiasis is very common among HIV patients and patients undergoing chemotherapy. The treatment of oral candidiasis is necessary once the disease causes discomfort and dysphagia, resulting in poor nutrition, slow recovery, and prolonged hospital stay [2,3]. Preliminary results obtained by our group with a new biotherapic prepared from Candida albicans (Candida 30x showed a great potential to reduce the candida yeast adhesion rate when the epithelial cells were pre-treated. This study is currently being developed with the evaluation of mutagenic and genotoxic potentials of several homeopathic solutions. Aims: The goal of this study was to assess the genotoxic and mutagenic potentials of different homeopathic potencies of C. albicans. Methodology: One part of C. albicans yeast obtained from Brazilian patient’s blood [4] was diluted in 9 parts of sterile water. This sample was submitted to 100 mechanical succussions (approximately 3 Hz, using Autic® Brazilian machine, originating the first dilution (1x. Then, 1 ml of this solution was diluted in 9 ml of solvent, submitted to 100 succussions, obtaining 2x potency. This procedure was successively repeated to obtain 30x potency, according to Brazilian Homeopathic Pharmacopoeia [5]. By the same technique, water vehicle was prepared until 30x to be used as control. All samples were prepared in sterile and aseptic conditions, using laminar flow cabinet, class II and were stored in the refrigerator (8ºC. The samples 1x, 6x, 12x, 18x, 24x and 30x of C. albicans and water 30x (vehicle control were analysed by: the Inductest, which assesses the ability of physical or chemical agents to promote lysogenic induction as a reflection of damage in DNA

  13. Genotoxicity of polyvinylpyrrolidone-coated silver nanoparticles in BEAS 2B cells.

    Science.gov (United States)

    Nymark, Penny; Catalán, Julia; Suhonen, Satu; Järventaus, Hilkka; Birkedal, Renie; Clausen, Per Axel; Jensen, Keld Alstrup; Vippola, Minnamari; Savolainen, Kai; Norppa, Hannu

    2013-11-08

    Silver nanoparticles (AgNPs) are widely utilized in various consumer products and medical devices, especially due to their antimicrobial properties. However, several studies have associated these particles with toxic effects, such as inflammation and oxidative stress in vivo and cytotoxic and genotoxic effects in vitro. Here, we assessed the genotoxic effects of AgNPs coated with polyvinylpyrrolidone (PVP) (average diameter 42.5±14.5 nm) on human bronchial epithelial BEAS 2B cells in vitro. AgNPs were dispersed in bronchial epithelial growth medium (BEGM) with 0.6 mg/ml bovine serum albumin (BSA). The AgNP were partially well-dispersed in the medium and only limited amounts (ca. 0.02 μg Ag(+) ion/l) could be dissolved after 24h. The zeta-potential of the AgNPs was found to be highly negative in pure water but was at least partially neutralized in BEGM with 0.6 mg BSA/ml. Cytotoxicity was measured by cell number count utilizing Trypan Blue exclusion and by an ATP-based luminescence cell viability assay. Genotoxicity was assessed by the alkaline single cell gel electrophoresis (comet) assay, the cytokinesis-block micronucleus (MN) assay, and the chromosomal aberration (CA) assay. The cells were exposed to various doses (0.5-48 μg/cm(2) corresponding to 2.5-240 μg/ml) of AgNPs for 4 and 24 h in the comet assay, for 48 h in the MN assay, and for 24 and 48 h in the CA assay. DNA damage measured by the percent of DNA in comet tail was induced in a dose-dependent manner after both the 4-h and the 24-h exposures to AgNPs, with a statistically significant increase starting at 16 μg/cm(2) (corresponding to 60.8 μg/ml) and doubling of the percentage of DNA in tail at 48 μg/cm(2). However, no induction of MN or CAs was observed at any of the doses or time points. The lack of induction of chromosome damage by the PVP-coated AgNPs is possibly due to the coating which may protect the cells from direct interaction with the AgNPs, either by reducing ion leaching from the

  14. Evaluation of the in vivo genotoxic effects of gamma radiation on the peripheral blood leukocytes of head and neck cancer patients undergoing radiotherapy.

    Science.gov (United States)

    Kadam, Samit B; Shyama, Soorambail K; Almeida, Valentine G

    2013-04-15

    The present study aimed to evaluate the genotoxic effects of ionizing radiation on non-target cells of Head and Neck Squamous Cell Carcinoma (HNSCC) patients exposed to various cumulative doses of gamma rays during radiotherapy. The ten patients (P1-P10) were treated with cobalt 60 gamma radiation (External Beam Radiotherapy) for a period of five to six weeks with a daily fraction of 2Gy for 5 days each week. The genotoxic effects of radiation (single strand breaks - SSBs) in these patients were analyzed using the alkaline single cell gel electrophoresis (SCGE) technique, with the Olive Tail Moment (OTM) as the critical parameter. A sample of each patient's peripheral blood before starting with radiotherapy (pre-therapy) served as the control, and blood collected at weekly time intervals during the course of the radiotherapy served as treated (10, 20, 30, 40, 50 and 60Gy) samples. In vivo radiosensitivity of these patients, as indicated by SSB's after the cumulative radiation doses at the various times, was assessed using Student's t-test. Significant DNA damage relative to the individual patient's pre-therapy baseline data was observed in all patients. Inter-individual variation of the genotoxic effects was analyzed using two-way ANOVA. The correlation between doses for the means of smoker and non-smoker patients was calculated using the Pearson test. The results of this study may indicate the need to reduce the daily radiotherapy dose further to prevent genotoxic effects on non-target cells, thus improving safety. Furthermore, these results may indicate that the estimation of DNA damage following exposure to a gamma radiation, as measured by the comet assay in whole blood leukocytes, can be used to screen human populations for radiation-induced genetic damage at the molecular level.

  15. Genotoxic and tumorigenic pyrrolizidine alkaloids in Chinese herbal plants

    Institute of Scientific and Technical Information of China (English)

    P.P. Fu; Q. Xia; M.W. Chou; G. Lin

    2005-01-01

    Pyrrolizidine alkaloids are a class of hepatotoxic and tumorigenic compounds detected in Chinese herbal plants,contaminated foods, and dietary supplements. In this review, the sources, toxicity, genotoxicity, tumorigenicity, and the metabolic pathways,particular the activation pathways leading to hepatotoxicity and tumorigenicity, of pyrrolizidine alkaloids are briefly discussed, with a focus on the most recent important findings concerning the genotoxic mechanism by which riddelliine liver tumors. This mechanism involves the formation of 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived DNA adducts and may be general to most carcinogenic pyrrolizidine alkaloids.

  16. DNA damage in lung after oral exposure to diesel exhaust particles in Big Blue (R) rats

    DEFF Research Database (Denmark)

    Müller, Anne Kirstine; Farombi, E.O.; Møller, P.

    2004-01-01

    . Lung tissue is a target organ for DEP induced cancer following inhalation. Recent studies have provided evidence that the lung is also a target organ for DNA damage and cancer after oral exposure to other complex mixtures of PAHs. The genotoxic effect of oral administration of DEP was investigated...

  17. ATP-dependent chromatin remodeling in the DNA-damage response

    NARCIS (Netherlands)

    H. Lans (Hannes); J.A. Marteijn (Jurgen); W. Vermeulen (Wim)

    2012-01-01

    textabstractThe integrity of DNA is continuously challenged by metabolism-derived and environmental genotoxic agents that cause a variety of DNA lesions, including base alterations and breaks. DNA damage interferes with vital processes such as transcription and replication, and if not repaired prope

  18. Cordyceps sinensis: Genotoxic Potential in Human Peripheral Blood Cells and Antigenotoxic Properties Against Hydrogen Peroxide by Comet Assay.

    Science.gov (United States)

    Vasiljevic, Jovana D; Zivkovic, Lada P; Cabarkapa, Andrea M; Bajic, Vladan P; Djelic, Ninoslav J; Spremo-Potparevic, Biljana M

    2016-06-01

    Context • Cordyceps sinensis (C sinensis) is a well-known, traditional, Chinese medicinal mushroom, valued for its beneficial properties for human health. C sinensis has been reported to have immunomodulatory, anticancer, antiaging, antioxidant and anti-inflammatory activity. Despite potential medicinal benefits, no previously published reports are available about the genotoxicity or antigenotoxicity of C sinensis, as detected by comet assay. Objective • The objective of the study was to evaluate both the genotoxic and antigenotoxic potential of an extract of C sinensis (CS extract) in human peripheral blood cells. Design • The research team designed a pilot study. Setting •The study was conducted at the Center for Biological Research, University of Belgrade, in Belgrade, Serbia. Participants • Participants were 6 healthy individuals (2 males and 4 females), between the ages of 20 and 45 y, recruited on a voluntary basis, who provided heparinized, peripheral blood samples. Intervention • Four concentrations of the CS extract-125 μg/mL, 250 μg/mL, 500 μg/mL, and 1000 μg/mL-were used in the treatment of tested blood cells from the blood samples. Three independent procedures were performed: (1) a genotoxicity assessment, (2) an antigenotoxicity assessment for pretreatment of human cells with the CS extract prior to their exposure to hydrogen peroxide (H2O2) (ie, an evaluation of the benefits of the CS extract as a preventive agent); and (3) posttreatment of human cells with the CS extract after their exposure to H2O2 (ie, an evaluation of the benefits of the CS extract as an interventional agent). Outcome Measures • Cells were graded by eye inspection into 5 classes, depending on the extent of DNA damage, representing: (1) class A-undamaged cells with no tail (95%).Results • The CS extract proved to be nongenotoxic because no induced DNA damage was detected at all tested concentrations. For the antigenotoxicity assessment of the pretreatment with

  19. Correlation between the genotoxicity endpoints measured by two different genotoxicity assays: comet assay and CBMN assay

    Directory of Open Access Journals (Sweden)

    Carina Ladeira

    2015-06-01

    The results concerning of positive findings by micronuclei and non significant ones by comet assay, are corroborated by Deng et al. (2005 study performed in workers occupationally exposed to methotrexate, also a cytostatic drug. According to Cavallo et al. (2009, the comet assay seems to be more suitable for the prompt evaluation of the genotoxic effects, for instance, of polycyclic aromatic hydrocarbons mixtures containing volatile substances, whereas the micronucleus test seems more appropriate to evaluate the effects of exposure to antineoplastic agents. However, there are studies that observed an increase in both the comet assay and the micronucleus test in nurses handling antineoplastic drugs, although statistical significance was only seen in the comet assay, quite the opposite of our results (Maluf & Erdtmann, 2000; Laffon et al. 2005.

  20. Combination of physico-chemical analysis, Allium cepa test system and Oreochromis niloticus erythrocyte based comet assay/nuclear abnormalities tests for cyto-genotoxicity assessments of treated effluents discharged from textile industries.

    Science.gov (United States)

    Hemachandra, Chamini K; Pathiratne, Asoka

    2016-09-01

    Bioassays for cyto-genotoxicity assessments are generally not required in current textile industry effluent discharge management regulations. The present study applied in vivo plant and fish based toxicity tests viz. Allium cepa test system and Oreochromis niloticus erythrocyte based comet assay and nuclear abnormalities tests in combination with physico-chemical analysis for assessing potential cytotoxic/genotoxic impacts of treated textile industry effluents reaching a major river (Kelani River) in Sri Lanka. Of the treated effluents tested from two textile industries, color in the Textile industry 1 effluents occasionally and color, biochemical oxygen demand and chemical oxygen demand in the Textile industry 2 effluents frequently exceeded the specified Sri Lankan tolerance limits for discharge of industrial effluents into inland surface waters. Exposure of A. cepa bulbs to 100% and 12.5% treated effluents from both industries resulted in statistically significant root growth retardation, mito-depression, and induction of chromosomal abnormalities in root meristematic cells in comparison to the dilution water in all cases demonstrating cyto-genotoxicity associated with the treated effluents. Exposure of O. niloticus to the 100% and 12.5% effluents, resulted in erythrocytic genetic damage as shown by elevated total comet scores and induction of nuclear abnormalities confirming the genotoxicity of the treated effluents even with 1:8 dilution. The results provide strong scientific evidence for the crucial necessity of incorporating cyto-genotoxicity impact assessment tools in textile industry effluent management regulations considering human health and ecological health of the receiving water course under chronic exposure.

  1. SIGNALING TO THE P53 TUMOR SUPPRESSOR THROUGH PATHWAYS ACTIVATED BY GENOTOXIC AND NON-GENOTOXIC STRESSES.

    Energy Technology Data Exchange (ETDEWEB)

    ANDERSON,C.W.APPELLA,E.

    2002-07-01

    The p53 tumor suppressor is a tetrameric transcription factor that is post-translational modified at {approx}18 different sites by phosphorylation, acetylation, or sumoylation in response to various cellular stress conditions. Specific posttranslational modifications, or groups of modifications, that result from the activation of different stress-induced signaling pathways are thought to modulate p53 activity to regulate cell fate by inducing cell cycle arrest, apoptosis, or cellular senescence. Here we review the posttranslational modifications to p53 and the pathways that produce them in response to both genotoxic and non-genotoxic stresses.

  2. Genotoxicity of low dose N-nitroso propoxur to human gastric cells.

    Science.gov (United States)

    Kuo, H H; Shyu, S S; Wang, T C

    2008-05-01

    Propoxur is among the most popular insect control agents in subtropical countries such as Taiwan. As a member of the N-methylcarbamate insecticide group, propoxur is notorious for its potential for conversion into highly genotoxic N-nitroso derivatives. Due to the fact that the stomach has been identified as the major target for N-nitroso N-methylcarbamates, this investigation used a human gastric cell line, SC-M1, in order to obtain results pertinent to the authentic adverse effects of this compound on human health. This report reveals that at dose levels inhibiting propoxur induced significant amounts of DNA damage. Most of the damaged DNA was repaired within 24 h after treatment removal, such that an outcome with a significant induction of chromosomal aberrations was not observed. Gene mutations and anchorage independence, on the other hand, were significantly induced by this same treatment. In conclusion, exposure to low doses of N-nitroso propoxur is not cytotoxic nor clastogenic, nevertheless, has the potential to increase genetic instability and, possibly as a result, to enhance the malignant potential of treated cells. We suggest that although the damaged DNA was repaired during the transient G2/M arrest period, it was probably not done in an appropriate way which would preserve the original genetic stability.

  3. In vivo and in vitro exposures for the evaluation of the genotoxic effects of lead on the Neotropical freshwater fish Prochilodus lineatus

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, V.; Cavalcante, D.G.S.M.; Vilela, M.B.F.A. [Laboratory of Animal Ecophysiology, Department of Physiological Sciences, Londrina State University, PB 6001, 86051-990 Londrina, PR (Brazil); Sofia, S.H. [Laboratory of Genetics and Animal Ecology, Department of General Biology, Londrina State University, PB 6001, 86051-990 Londrina, PR (Brazil); Martinez, C.B.R., E-mail: cbueno@uel.br [Laboratory of Animal Ecophysiology, Department of Physiological Sciences, Londrina State University, PB 6001, 86051-990 Londrina, PR (Brazil)

    2011-08-15

    In the present study, in vivo and in vitro exposures were used to assess the genotoxicity of lead (Pb) to the freshwater fish Prochilodus lineatus. The comet assay using blood, liver and gill cells, and the occurrence of micronuclei (MN) and other erythrocytic nuclear abnormalities (ENA) were used to assess the genotoxic potential of lead in vivo. Metallothionein content (MT) was measured in fish liver in order to evaluate the protection of fish against Pb toxicity. Fish erythrocytes were exposed to Pb in vitro (1, 3 and 6 h) and the number of viable cells, DNA integrity, using the comet assay, and lysosomal membrane stability, measured by the neutral red retention assay (NRRA) were analyzed. The results of the comet assay after in vivo toxicity tests (6, 24 and 96 h) showed that Pb was genotoxic for all the three tissues analyzed after 96 h exposure. A significant increase in liver MT content was observed after 6 and 24 h of Pb exposure. MN frequency did not increase after Pb exposures, but the frequency of the other ENA, such as kidney-shaped nuclei, segmented nuclei and lobed nuclei, showed a significant increase after 24 and 96 h, indicating that ENA is a better biomarker for Pb exposure than MN alone after short-term exposures. The results of the comet assay performed with erythrocytes in vitro exposed to lead confirmed its genotoxic effect and showed that DNA damage increased with increasing exposure time. Moreover, the NRRA clearly indicated that Pb induces a destabilization of the lysosomal membrane. These results demonstrate the potential genotoxicity and cytotoxicity of lead after acute exposures.

  4. In vivo and in vitro exposures for the evaluation of the genotoxic effects of lead on the Neotropical freshwater fish Prochilodus lineatus.

    Science.gov (United States)

    Monteiro, V; Cavalcante, D G S M; Viléla, M B F A; Sofia, S H; Martinez, C B R

    2011-08-01

    In the present study, in vivo and in vitro exposures were used to assess the genotoxicity of lead (Pb) to the freshwater fish Prochilodus lineatus. The comet assay using blood, liver and gill cells, and the occurrence of micronuclei (MN) and other erythrocytic nuclear abnormalities (ENA) were used to assess the genotoxic potential of lead in vivo. Metallothionein content (MT) was measured in fish liver in order to evaluate the protection of fish against Pb toxicity. Fish erythrocytes were exposed to Pb in vitro (1, 3 and 6 h) and the number of viable cells, DNA integrity, using the comet assay, and lysosomal membrane stability, measured by the neutral red retention assay (NRRA) were analyzed. The results of the comet assay after in vivo toxicity tests (6, 24 and 96 h) showed that Pb was genotoxic for all the three tissues analyzed after 96 h exposure. A significant increase in liver MT content was observed after 6 and 24 h of Pb exposure. MN frequency did not increase after Pb exposures, but the frequency of the other ENA, such as kidney-shaped nuclei, segmented nuclei and lobed nuclei, showed a significant increase after 24 and 96 h, indicating that ENA is a better biomarker for Pb exposure than MN alone after short-term exposures. The results of the comet assay performed with erythrocytes in vitro exposed to lead confirmed its genotoxic effect and showed that DNA damage increased with increasing exposure time. Moreover, the NRRA clearly indicated that Pb induces a destabilization of the lysosomal membrane. These results demonstrate the potential genotoxicity and cytotoxicity of lead after acute exposures.

  5. Normalization of nano-sized TiO2-induced clastogenicity, genotoxicity and mutagenicity by chlorophyllin administration in mice brain, liver, and bone marrow cells.

    Science.gov (United States)

    El-Ghor, Akmal A; Noshy, Magda M; Galal, Ahmad; Mohamed, Hanan Ramadan H

    2014-11-01

    The intensive uses of titanium dioxide (TiO2) nanoparticles in sunscreens, toothpaste, sweats, medications, etc. making humans exposed to it daily by not little amounts and also increased its risks including genotoxicity. Thus, the present study was designed as one way to reduce nano-titanium-induced clastogenicity, genotoxicity, and mutagenicity in mice by co-administration of the free radical scavenger chlorophyllin (CHL). In addition, markers of oxidative stress were detected to shed more light on mechanism(s) underlying nano-sized TiO2 genotoxicity. Male mice were exposed to multiple injection into the abdominal cavity for five consecutive days with either CHL (40 mg/kg bw/day), or each of three dose levels of nano-sized TiO2 (500, 1000, or 2000 mg/kg bw/day) alone, or both simultaneously and sacrificed by cervical dislocation 24 h after the last treatment. After CHL co-administration, the observed dose-dependent genotoxicity of TiO2 nanoparticles indicated by the significant elevations in frequencies of both micronuclei and DNA damage induction was significantly decreased and returned to the negative control level. The observed induced mutations in p53 exons 5, 7, & 8 and 5 & 8 in the liver and brain, respectively, were declined in most cases. Moreover, CHL significantly decreased hepatic malondialdehyde level and significantly increased glutathione level and superoxide dismutase, catalase, and glutathione peroxidase activities that were significantly disrupted in animal groups treated with nano-TiO2 alone. In conclusion, the evidenced in vivo genotoxicity of nano-TiO2 in the present study was normalized after CHL co-administration which supports the previously suggested oxidative stress as the possible mechanism for titanium toxicity.

  6. Biomonitoring of the genotoxic effects and oxidative potentials of commercial edible dung beetles (Onitis sp.), grasshopper (Caelifera sp.) and mole crickets (Gryllotalpa sp.) in vitro.

    Science.gov (United States)

    Koc, Kubra; Incekara, Umit; Turkez, Hasan

    2014-09-01

    In this investigation, the genotoxic and oxidative effects of water soluble extracts of dung beetles, flying grasshopper and mole crickets have been assessed on cultured human blood cells. The extracts were added to the culture tubes at 12 different concentrations (0-2000 ppm). Micronucleus test was used to monitor the DNA and the chromosomal damage produced by aqueous extracts in vitro. In addition, to assess the oxidative effects, total antioxidant capacity (TAC) and total oxidant status (TOS) levels were also measured. Our results indicated that these extracts did not show genotoxic effects at the tested concentrations. However, the extracts caused dose-dependent alterations in both TAC and TOS levels. Based on the findings, it was concluded that the studied insects can be consumed safely, but it is necessary to consider the cellular damages which are likely to appear depending on oxidative stress at higher concentrations. It has also been suggested that this in vitro approach for oxidative and genotoxicity assessments may be useful to evaluate the potential health risks of edible insects.

  7. Pyruvate remediation of cell stress and genotoxicity induced by haloacetic acid drinking water disinfection by-products.

    Science.gov (United States)

    Dad, Azra; Jeong, Clara H; Pals, Justin A; Wagner, Elizabeth D; Plewa, Michael J

    2013-10-01

    Monohaloacetic acids (monoHAAs) are a major class of drinking water disinfection by-products (DBPs) and are cytotoxic, genotoxic, mutagenic, and teratogenic. We propose a model of toxic action based on monoHAA-mediated inhibition of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a target cytosolic enzyme. This model predicts that GAPDH inhibition by the monoHAAs will lead to a severe reduction of cellular ATP levels and repress the generation of pyruvate. A loss of pyruvate will lead to mitochondrial stress and genomic DNA damage. We found a concentration-dependent reduction of ATP in Chinese hamster ovary cells after monoHAA treatment. ATP reduction per pmol monoHAA followed the pattern of iodoacetic acid (IAA) > bromoacetic acid (BAA) > chloroacetic acid (CAA), which is the pattern of potency observed with many toxicological endpoints. Exogenous supplementation with pyruvate enhanced ATP levels and attenuated monoHAA-induced genomic DNA damage as measured with single cell gel electrophoresis. These data were highly correlated with the SN 2 alkylating potentials of the monoHAAs and with the induction of toxicity. The results from this study strongly support the hypothesis that GAPDH inhibition and the possible subsequent generation of reactive oxygen species is linked with the cytotoxicity, genotoxicity, teratogenicity, and neurotoxicity of these DBPs.

  8. Genotoxic and mutagenic effects of polluted surface water in the midwestern region of Brazil using animal and plant bioassays

    Directory of Open Access Journals (Sweden)

    Priscila Leocádia Rosa Dourado

    Full Text Available Abstract This study aimed to evaluate DNA damage in animal and plant cells exposed to water from the Água Boa stream (Dourados, Mato Grosso do Sul, Brazil by using bioassays, and to identify the chemical compounds in the water to determine the water quality in the area. Through the cytotoxicity bioassay with Allium cepa, using micronucleus test, and comet assay, using Astyanax altiparanae fish, the results indicated that biological samples were genetically altered. Micronuclei were observed in erythrocytes of A. altiparanae after exposure to water from locations close to industrial waste discharge. The highest DNA damage observed with the comet assay in fish occurred with the exposure to water from locations where the presence of metals (Cu, Pb, Cd, Ni was high, indicating the possibility of genotoxic effects of these compounds. Thus, these results reinforce the importance of conducting genotoxicity tests for developing management plans to improve water quality, and indicate the need for waste management before domestic and industrial effluents are released into the rivers and streams.

  9. Genotoxicity evaluation of locally produced dental porcelain--an in vitro study using the Ames and Comet assays.

    Science.gov (United States)

    Noushad, Mohammed; Kannan, Thirumulu Ponnuraj; Husein, Adam; Abdullah, Haswati; Ismail, Abdul Rashid

    2009-09-01

    The aim of this study was to determine the genotoxicity of a locally produced dental porcelain (Universiti Sains Malaysia, Malaysia) using the Ames and Comet assays. In the Ames assay, four genotypic variants of the Salmonella strains (TA98, TA100, TA1537 and TA1535) carrying mutations in several genes were used. The dental porcelain was incubated with these four strains in five different doses both in the presence and absence of metabolic activation (S9) and the result was assessed based on the number of revertant colonies. Concurrently, appropriate positive controls were used so as to validate the test. The average number of revertant colonies per plate treated with locally produced dental porcelain was less than double as compared to that of negative control. In the Comet assay, L929 (CCL-1 ATCC, USA) mouse fibroblast cells were treated with the dental porcelain in three different concentrations along with concurrent negative and positive controls. The tail moment which was used as a measurement of DNA damage was almost equal to that of the negative control, suggesting that the locally produced dental porcelain did not induce any DNA damage. The results indicated that the locally produced dental porcelain is non-genotoxic under the present test conditions.

  10. Cytotoxicity, oxidative stress and genotoxicity induced by glass fibers on human alveolar epithelial cell line A549.

    Science.gov (United States)

    Rapisarda, Venerando; Loreto, Carla; Ledda, Caterina; Musumeci, Giuseppe; Bracci, Massimo; Santarelli, Lory; Renis, Marcella; Ferrante, Margherita; Cardile, Venera

    2015-04-01

    Man-made vitreous fibers have been widely used as insulation material as asbestos substitutes; however their morphology and composition raises concerns. In 1988 the International Agency for Research on Cancer classified fiberglass, rock wool, slag wool, and ceramic fibers as Group 2B, i.e. possibly carcinogenic to humans. In 2002 it reassigned fiberglass, rock and slag wool, and continuous glass filaments to Group 3, not classifiable as carcinogenic to humans. The aim of this study was to verify the cytotoxic and genotoxic effects and oxidative stress production induced by in vitro exposure of human alveolar epithelial cells A549 to glass fibers with a predominant diameter 5 μm (93%). A549 cells were incubated with 5, 50, or 100 μg/ml (2.1, 21, and 42 μg/cm(2), respectively) of glass fibers for 72 h. Cytotoxicity and DNA damage were tested by the MTT and the Comet assay, respectively. Oxidative stress was determined by measuring inducible nitric oxide synthase (iNOS) expression by Western blotting, production of nitric oxide (NO) with Griess reagent, and concentration of reactive oxygen species by fluorescent quantitative analysis with 2',7'-dichlorofluorescein-diacetate (DCFH-DA). The results showed that glass fiber exposure significantly reduced cell viability and increased DNA damage and oxidative stress production in a concentration-dependent manner, demonstrating that glass fibers exert cytotoxic and genotoxic effects related to increased oxidative stress on the human alveolar cell line A549.

  11. In vitro biomonitoring of the genotoxic and oxidative potentials of two commonly eaten insects in southwestern Nigeria.

    Science.gov (United States)

    Memiş, Eray; Türkez, Hasan; Incekara, Ümit; Banjo, Adedoyin Davies; Fasunwon, Bamidele Temitope; Toğar, Başak

    2013-02-01

    In this study, the cytogenetic and oxidative effects of water soluble extracts of two commonly eaten insects, Zonocerus variegatus (Orthoptera: Pyrgomorphidae) and Oryctes boas (Solanales: Solanaceae), in southwestern Nigeria were evaluated on cultured human blood cells. The extracts were added to the cultures at various concentrations (0-2000 ppm). The chromosome aberration and micronucleus tests were used to find out the DNA and chromosomal damage potentials in vitro by aqueous insect extracts. To assess the oxidative effects of these insect extracts, total antioxidant capacity (TAC) and total oxidant status (TOS) levels were also measured. Our results indicated that these extracts did not show genotoxic effects at the tested concentrations. However, the extracts caused dose-dependent alterations in both TAC and TOS levels. Based on the findings, it was concluded that the studied insects can be consumed safely, but it is necessary to consider the cellular damages that are likely to appear depending on the oxidative stress. We also suggest that this in vitro approach for oxidative and genotoxicity assessments may be useful to compare the potential health risks of edible insects.

  12. The genotoxic effects of benzo[a]pyrene and methamidophos on black porgy evaluated by comet assay

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In this study, two common pollutants (benzo[a]pyrene and methamidophos) in marine environment were tested by comet assay for their inducement of in vivo genotoxic effect to the blood cells of black porgy (Acanthopagrus schlegeli). The fish was exposed to 2 μg/L of benzo[a]pyrene (BaP) and methamidophos, and their mixture. The assay was performed on whole blood at 2 h, 5 h, 24 h and 96 h exposure intervals. A significant increase in DNA damage was observed in each treatment with the pollutants. Additive effect of BaP and methamidophos was also found in the experiment. However, the decrease ratios of DNA damage for 5 h and 96 h exposure interals compared with 2 h and 24 h exposure ones, respectively, were noticed. This phenomenon may be explained by the function of repairing process via enzyme cytochrome P450 in the animal. Evidence of the genotoxicity of organophosphorus pesticides (OPs) and polynuclear aromatic hydrocarbons (PAHs) on marine fish are discussed in this paper.

  13. The genotoxic effects of benzo[a]pyrene and methamidophos on black porgy evaluated by comet assay

    Science.gov (United States)

    Liu, Rixian; Hong, Huasheng; Wang, Xinhong; Wang, Kejian; Wang, Chunguang

    2005-12-01

    In this study, two common pollutants (benzo[a]pyrene and methamidophos) in marine environment were tested by comet assay for their inducement of in vivo genotoxic effect to the blood cells of black porgy ( Acanthopagrus schlegeli). The fish was exposed to 2 μg/L of benzo[a]pyrene (BaP) and methamidophos, and their mixture. The assay was performed on whole blood at 2 h, 5 h, 24 h and 96 h exposure intervals. A significant increase in DNA damage was observed in each treatment with the pollutants. Additive effect of BaP and methamidophos was also found in the experiment. However, the decrease ratios of DNA damage for 5 h and 96 h exposure interals compared with 2 h and 24 h exposure ones, respectively, were noticed. This phenomenon may be explained by the function of repairing process via enzyme cytochrome P450 in the animal. Evidence of the genotoxicity of organophosphorus pesticides (OPs) and polynuclear aromatic hydrocarbons (PAHs) on marine fish are discussed in this paper.

  14. Identification of early target genes of aflatoxin B1 in human hepatocytes, inter-individual variability and comparison with other genotoxic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Josse, Rozenn; Dumont, Julie; Fautrel, Alain; Robin, Marie-Anne; Guillouzo, André, E-mail: andre.guillouzo@univ-rennes1.fr

    2012-01-15

    Gene expression profiling has recently emerged as a promising approach to identify early target genes and discriminate genotoxic carcinogens from non-genotoxic carcinogens and non-carcinogens. However, early gene changes induced by genotoxic compounds in human liver remain largely unknown. Primary human hepatocytes and differentiated HepaRG cells were exposed to aflatoxin B1 (AFB1) that induces DNA damage following enzyme-mediated bioactivation. Gene expression profile changes induced by a 24 h exposure of these hepatocyte models to 0.05 and 0.25 μM AFB1 were analyzed by using oligonucleotide pangenomic microarrays. The main altered signaling pathway was the p53 pathway and related functions such as cell cycle, apoptosis and DNA repair. Direct involvement of the p53 protein in response to AFB1 was verified by using siRNA directed against p53. Among the 83 well-annotated genes commonly modulated in two pools of three human hepatocyte populations and HepaRG cells, several genes were identified as altered by AFB1 for the first time. In addition, a subset of 10 AFB1-altered genes, selected upon basis of their function or tumor suppressor role, was tested in four human hepatocyte populations and in response to other chemicals. Although they exhibited large variable inter-donor fold-changes, several of these genes, particularly FHIT, BCAS3 and SMYD3, were found to be altered by various direct and other indirect genotoxic compounds and unaffected by non-genotoxic compounds. Overall, this comprehensive analysis of early gene expression changes induced by AFB1 in human hepatocytes identified a gene subset that included several genes representing potential biomarkers of genotoxic compounds. -- Highlights: ► Gene expression profile changes induced by aflatoxin B1 in human hepatocytes. ► AFB1 modulates various genes including tumor suppressor genes and proto-oncogenes. ► Important inter-individual variations in the response to AFB1. ► Some genes also altered by other

  15. Evaluation of the genotoxic activity of dicamba and atrazine herbicides in several Mexican and South American varieties of sweetcorn (Zea mays L.).

    Science.gov (United States)

    Reynoso, M S; Alvarez, C M; De la Cruz, L; Escoto, M D; Sánchez, J J G

    2015-12-11

    Corn is a major crop and various herbicides are used to maximize its production, which include a dicamba-atrazine mixture. This has great advantages, but can also induce DNA damage. Genotoxic activity was assessed by comet assay following application of two concentrations of dicamba-atrazine: 1000-2000 and 2000-4000 ppm. Apical meristem leaf nuclei from 119 varieties of sweetcorn plants from Mexico and South America, and from five commercial sweetcorn hybrids were used. Each accession comprised two individuals per concentration and two controls. Significant genotoxic activity (P 0.05) except (P atrazine mixture caused genetic damage to corn plants, and it suggested that Mexican sweetcorn is more sensitive to dicamba-atrazine than the maize varieties from South America. Neither hybrid status nor the origin avoids DNA damage caused by Marvel. Thus, maize can be useful as a biomonitor of genetic damage induced by chemicals and to identify possible phenotypes based upon the amount of genetic damage induced by herbicides and selection of resistant genotypes.

  16. Assessment of the genotoxic potential along the Danube River by application of the comet assay on haemocytes of freshwater mussels: The Joint Danube Survey 3.

    Science.gov (United States)

    Kolarević, Stoimir; Kračun-Kolarević, Margareta; Kostić, Jovana; Slobodnik, Jaroslav; Liška, Igor; Gačić, Zoran; Paunović, Momir; Knežević-Vukčević, Jelena; Vuković-Gačić, Branka

    2016-01-01

    In this study we assessed the level of genotoxic pollution along the Danube River by measuring the level of DNA damage in the haemocytes of freshwater mussels of Unio sp. (Unio pictorum/Unio tumidus) and Sinanodonta woodiana. The comet assay was used for the assessment of DNA damage. The research was performed on 34 out of 68 sites analysed within the Joint Danube Survey 3 - the world's biggest river research expedition of its kind in 2013. During research, 2285 river kilometres were covered with an average distance of 68 km between the sites. The complex data set on concentrations of various substances present in water, suspended particulate matter and sediment on investigated sites gave the opportunity to identify the groups of xenobiotics which mostly affect the studied biomarker - DNA damage. The highest levels of DNA damage were recorded in the section VI (Panonnian Plain), which is under the impact of untreated wastewater discharges. Both positive and negative influences of the large tributaries on the level of genotoxicity in the Danube River were evident. Significant correlation in response was detected between the studied species of freshwater mussels. The level of DNA damage in mussels correlated with concentrations of compounds from the group of hazardous priority substances (polycyclic aromatic hydrocarbons), persistent organic pollutants (dioxins) and emerging pollutants (Oxazepam, Chloridazon-desphenyl).

  17. Genotoxic Maillard byproducts in current phytopharmaceutical preparations of Echinodorus grandiflorus

    Directory of Open Access Journals (Sweden)

    ELISANGELA C. LIMA-DELLAMORA

    2014-09-01

    Full Text Available Extracts of Echinodorus grandiflorus obtained from dried leaves by three different techniques were evaluated by bacterial lysogenic induction assay (Inductest in relation to their genotoxic properties. Before being added to test cultures, extracts were sterilized either by steam sterilization or ultraviolet light. Only the extracts prepared by infusion and steam sterilized have shown genotoxic activity. The phytochemical analysis revealed the presence of the flavonoids isovitexin, isoorientin, swertisin and swertiajaponin, isolated from a genotoxic fraction. They were assayed separately and tested negative in the Inductest protocol. The development of browning color and sweet smell in extracts submitted to heat, prompted further chemical analysis in search for Maillard's reaction precursors. Several aminoacids and reducing sugars were cast in the extract. The presence of characteristic Maillard's melanoidins products was determined by spectrophotometry in the visible region and the inhibition of this reaction was observed when its characteristic inhibitor, sodium bisulfite, was added prior to heating. Remarkably, this is the first paper reporting on the appearance of such compounds in a phytomedicine preparation under a current phytopharmaceutical procedure. The genotoxic activity of such heat-prepared infusions imply in some risk of developing degenerative diseases for patients in long-term, uncontrolled use of such phytomedicines.

  18. Genotoxicity of Pesticide Waste Contaminated Soil and Its Leachate

    Institute of Scientific and Technical Information of China (English)

    S. D. SIVANESAN; K. KRISHNAMURTHI; S. D. WACHASUNDER; T. CHAKRABARTI

    2004-01-01

    Improper land disposal of hazardous waste can result in leaching of hazardous constituents which may contaminate ground and surface water leading to adverse impact on human health and environment consequences. The present study utilized mammalian cell culture for the genotoxicity assessment of waste and its leachate. Methods Genotoxic potential and chemical analysis of pesticide derived tarry waste contaminated soil extract and its leachate was assessed using in vitro human lymphocyte cultures and GC-MS. Results The investigation revealed that the soil extract could cause significant to highly significant genotoxicity in the form of DNA strand break at 25 μL (P<0.01), 50 μL, 100 μL and 200 μL (P<0.001) and chromosomal aberration at 25 μL (P<0.01) and 50 μL and 100 μL (P<0.001). The leachate could cause significant DNA strand break and chromosomal aberration only at 100 μL and 200 μL (P<0.01) dose levels. Conclusion The genotoxicity observed is attributed to carbaril and tetra methyl naphthyl carbamate, the major ingredients of the extracts, as revealed by GC-MS.

  19. Genotoxicity studies on a high-purity rebaudioside A preparation.

    Science.gov (United States)

    Williams, Lonnie D; Burdock, George A

    2009-08-01

    Rebaudioside A (Reb A) is a steviol glycoside isolated from the leaves of the Stevia rebaudiana plant. This non-nutritive, natural sweetener is reported to be 250-450 times sweeter than sucrose and has potential for wide use in the US diet, and is used in Japan and South America today. The safety of Reb A has been investigated in several recently published studies and information on genotoxicity is described herein. Reb A was investigated for its potential to induce genotoxicity in three in vitro and two in vivo assays (conducted according to OECD guidelines). Reb A was non-mutagenic in an Ames test using Salmonella typhimurium and Escherichia coli, in a chromosomal aberration test using Chinese Hamster V79 cells and in a mouse lymphoma assay using L5178Y+/- cells, all studies were conducted at concentrations up to 5000 microg/ml, with and without metabolic activation. Also, Reb A was non-genotoxic in a bone marrow micronucleus test in mice at doses up 750 mg/kg bw and in an unscheduled DNA synthesis test in rats at 2000 mg/kg bw. These studies provide additional evidence that Reb A is not genotoxic at the doses tested and further support the generally recognized as safe determination of Reb A.

  20. Genotoxicity in native fish associated with agricultural runoff events

    Science.gov (United States)

    Whitehead, A.; Kuivila, K.M.; Orlando, J.L.; Kotelevtsev, S.; Anderson, S.L.

    2004-01-01

    The primary objective of the present study was to test whether agricultural chemical runoff was associated with in-stream genotoxicity in native fish. Using Sacramento sucker (Catostomus occidentalis), we combined field-caging experiments in an agriculturally dominated watershed with controlled laboratory exposures to field-collected water samples, and we coupled genotoxicity biomarker measurements in fish with bacterial mutagenicity analysis of water samples. We selected DNA strand breakage as a genotoxicity biomarker and Ames Salmonella mutagenicity tests as a second, supporting indicator of genotoxicity. Data from experiments conducted during rainfall runoff events following winter application of pesticides in 2000 and 2001 indicated that DNA strand breaks were significantly elevated in fish exposed to San Joaquin River (CA, USA) water (38.8, 28.4, and 53.6% DNA strand breakage in year 2000 field, year 2000 lab, and year 2001 field exposures, respectively) compared with a nearby reference site (15.4, 8.7, and 12.6% DNA strand breakage in year 2000 field, year 2000 lab, and year 2001 field exposures, respectively). Time-course measurements in field experiments supported a linkage between induction of DNA strand breakage and the timing of agricultural runoff. San Joaquin River water also caused significant reversion mutation in two Ames Salmonella tester strains. Salmonella mutagenicity corroborated in-stream effects, further strengthening a causal relationship between runoff events and genotoxicity. Potentially responsible agents are discussed in the context of timing of runoff events in the field, concordance between laboratory and field exposures, pesticide application patterns in the drainage, and analytical chemistry data.

  1. Evaluation of the genotoxicity/mutagenicity and antigenotoxicity/antimutagenicity induced by propolis and Baccharis dracunculifolia, by in vitro study with HTC cells.

    Science.gov (United States)

    Roberto, Matheus Mantuanelli; Matsumoto, Sílvia Tamie; Jamal, Cláudia Masrouah; Malaspina, Osmar; Marin-Morales, Maria Aparecida

    2016-06-01

    The ethanolic extract of propolis, especially the Brazilian green type, is widely and mainly used for therapeutic purposes despite the lack of knowledge about its effects and its cellular mode of action. This type of propolis, derived from Baccharis dracunculifolia (alecrim-do-campo), has been extensively commercialized and the consumers use it to enhance health. This work aimed to assess the genotoxic/mutagenic and antigenotoxic/antimutagenic potentials of the ethanolic extracts of Brazilian green propolis and of B. dracunculifolia, on mammalian cells. It was not observed genotoxic and mutagenic effects by both extracts. After evaluate the exposure of the cells to each extract with a recognized mutagen, simultaneously, the results showed a significant reduction on DNA damage. The experiment carried out with a pre-incubation period was more effective than without incubation test, showing that the tested extracts were able to inactivate the mutagen before it could react with the DNA.

  2. Investigation on the mechanisms of genotoxicity of butadiene, styrene and their combination in human lymphocytes using the Comet assay.

    Science.gov (United States)

    Cemeli, Eduardo; Mirkova, Ekaterina; Chiuchiarelli, Giorgia; Alexandrova, Elena; Anderson, Diana

    2009-05-12

    The toxicity of butadiene and styrene is exerted by their metabolites. Such metabolites have been extensively scrutinized at the in vitro level demonstrating evident genotoxic properties. In monitoring, a diverse range of outcomes has been produced. Additionally, epidemiological studies in rubber workers face difficulties of data interpretation due to the changeability and multiple exposures of the workers as well as to confounding factors inherent to the cohorts. Nevertheless, toxicity has been associated with a significant trend of increasing the risk of leukaemia in employees at the styrene-butadiene rubber industry. Thus, further effort must be made to distinguish the exposures to each chemical over time and to characterize their interrelationships. The present investigation focuses on the effects and mechanisms of damage of the mixture styrene-butadiene by examining its metabolites: styrene oxide (SO), butadiene monoepoxide (BME) and butadiene diepoxide (BDE) respectively. The in vitro Comet assay on frozen lymphocytes has been employed to ascertain the DNA damage patterns for the styrene-butadiene metabolites combined and on their own. Different patterns were observed for the mixture and each of its components. This study has also led to determining the mechanism of damage of the mixture and the compounds. With regard to the presence of reactive oxygen species (ROS), co-treatment with catalase does not modulate the genotoxicity of the mixture but it does modulate its components. The outcomes also indicate that the mixture induces cross-links and this is due to the influence of BDE in the mixture, being more evident as the concentration of BDE increases. An investigation on the sensitivity of lymphocytes from occupationally un/exposed subjects to in vitro exposure of the mixture and its components revealed that occupationally exposed subjects had a substantially higher background of DNA damage and a lower sensitivity to the metabolites of styrene, 1

  3. Comparison of the genotoxic effects induced by 50 Hz extremely low-frequency electromagnetic fields and 1800 MHz radiofrequency electromagnetic fields in GC-2 cells.

    Science.gov (United States)

    Duan, Weixia; Liu, Chuan; Zhang, Lei; He, Mindi; Xu, Shangcheng; Chen, Chunhai; Pi, Huifeng; Gao, Peng; Zhang, Yanwen; Zhong, Min; Yu, Zhengping; Zhou, Zhou

    2015-03-01

    Extremely low-frequency electromagnetic fields (ELF-EMF) and radiofrequency electromagnetic fields (RF-EMF) have been considered to be possibly carcinogenic to humans. However, their genotoxic effects remain controversial. To make experiments controllable and results comparable, we standardized exposure conditions and explored the potential genotoxicity of 50 Hz ELF-EMF and 1800 MHz RF-EMF. A mouse spermatocyte-derived GC-2 cell line was intermittently (5 min on and 10 min off) exposed to 50 Hz ELF-EMF at an intensity of 1, 2 or 3 mT or to RF-EMF in GSM-Talk mode at the specific absorption rates (SAR) of 1, 2 or 4 W/kg. After exposure for 24 h, we found that neither ELF-EMF nor RF-EMF affected cell viability using Cell Counting Kit-8. Through the use of an alkaline comet assay and immunofluorescence against γ-H2AX foci, we found that ELF-EMF exposure resulted in a significant increase of DNA strand breaks at 3 mT, whereas RF-EMF exposure had insufficient energy to induce such effects. Using a formamidopyrimidine DNA glycosylase (FPG)-modified alkaline comet assay, we observed that RF-EMF exposure significantly induced oxidative DNA base damage at a SAR value of 4 W/kg, whereas ELF-EMF exposure did not. Our results suggest that both ELF-EMF and RF-EMF under the same experimental conditions may produce genotoxicity at relative high intensities, but they create different patterns of DNA damage. Therefore, the potential mechanisms underlying the genotoxicity of different frequency electromagnetic fields may be different.

  4. Epigenetic mechanisms of mouse interstrain variability in genotoxicity of the environmental toxicant 1,3-butadiene.

    Science.gov (United States)

    Koturbash, Igor; Scherhag, Anne; Sorrentino, Jessica; Sexton, Kenneth; Bodnar, Wanda; Swenberg, James A; Beland, Frederick A; Pardo-Manuel Devillena, Fernando; Rusyn, Ivan; Pogribny, Igor P

    2011-08-01

    1,3-Butadiene (BD) is a common environmental contaminant classified as "carcinogenic to humans." Formation of BD-induced DNA adducts plays a major role in its carcinogenicity. BD is also an epigenotoxic agent (i.e., it affects DNA and histone methylation in the liver). We used a panel of genetically diverse inbred mice (NOD/LtJ, CAST/EiJ, A/J, WSB/EiJ, PWK/PhJ, C57BL/6J, and 129S1/SvImJ) to assess whether BD-induced genotoxic and epigenotoxic events may be subject to interstrain differences. Mice (male, 7 weeks) were exposed via inhalation to 0 or 625 ppm BD for 6 h/day and 5 days/week for 2 weeks and liver BD-DNA adducts, epigenetic alterations, and liver toxicity were assessed. N-7-(2,3,4-trihydroxybut-1-yl)-guanine adducts were detected in all strains after exposure, yet BD-induced DNA damage in CAST/EiJ mice was two to three times lower. Epigenetic effects of BD were most prominent in C57BL/6J mice where loss of global DNA methylation and loss of trimethylation of histone H3 lysine 9, histone H3 lysine 27, and histone H4 lysine 20, accompanied by dysregulation of liver gene expression indicative of hepatotoxicity, were found. Interestingly, we observed an increase in histone methylation in the absence of changes in gene expression and DNA methylation in CAST/EiJ strain. We hypothesized that mitigated genotoxicity of BD in CAST/EiJ mice may be due to chromatin condensation. Indeed, we show that in response to BD exposure, chromatin condensation occurs in CAST/EiJ, whereas the opposite effect is observed in C57BL/6J mice. These findings demonstrate that interstrain susceptibility to genotoxicity by a well-known environmental carcinogen may be due to strain-specific epigenetic events in response to the exposure.

  5. Magnetite Nanoparticles Induce Genotoxicity in the Lungs of Mice via Inflammatory Response

    Science.gov (United States)

    Totsuka, Yukari; Ishino, Kousuke; Kato, Tatsuya; Goto, Sumio; Tada, Yukie; Nakae, Dai; Watanabe, Masatoshi; Wakabayashi, Keiji

    2014-01-01

    Nanomaterials are useful for their characteristic properties and are commonly used in various fields. Nanosized-magnetite (MGT) is widely utilized in medicinal and industrial fields, whereas their toxicological properties are not well documented. A safety assessment is thus urgently required for MGT, and genotoxicity is one of the most serious concerns. In the present study, we examined genotoxic effects of MGT using mice and revealed that DNA damage analyzed by a comet assay in the lungs of imprinting control region (ICR) mice intratracheally instilled with a single dose of 0.05 or 0.2 mg/animal of MGT was approximately two- to three-fold higher than that of vehicle-control animals. Furthermore, in gpt delta transgenic mice, gpt mutant frequency (MF) in the lungs of the group exposed to four consecutive doses of 0.2 mg MGT was significantly higher than in the control group. Mutation spectrum analysis showed that base substitutions were predominantly induced by MGT, among which G:C to A:T transition and G:C to T:A transversion were the most significant. To clarify the mechanism of mutation caused by MGT, we analyzed the formation of DNA adducts in the lungs of mice exposed to MGT. DNA was extracted from lungs of mice 3, 24, 72 and 168 h after intratracheal instillation of 0.2 mg/body of MGT, and digested enzymatically. 8-Oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and lipid peroxide-related DNA adducts were quantified by stable isotope dilution liquid chromatography-mass spectrometry (LC-MS/MS). Compared with vehicle control, these DNA adduct levels were significantly increased in the MGT-treated mice. In addition to oxidative stress- and inflammation related-DNA adduct formations, inflammatory cell infiltration and focal granulomatous formations were also observed in the lungs of MGT-treated mice. Based on these findings, it is suggested that inflammatory responses are probably involved in the genotoxicity induced by MGT in the lungs of mice.

  6. Magnetite Nanoparticles Induce Genotoxicity in the Lungs of Mice via Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Yukari Totsuka

    2014-03-01

    Full Text Available Nanomaterials are useful for their characteristic properties and are commonly used in various fields. Nanosized-magnetite (MGT is widely utilized in medicinal and industrial fields, whereas their toxicological properties are not well documented. A safety assessment is thus urgently required for MGT, and genotoxicity is one of the most serious concerns. In the present study, we examined genotoxic effects of MGT using mice and revealed that DNA damage analyzed by a comet assay in the lungs of imprinting control region (ICR mice intratracheally instilled with a single dose of 0.05 or 0.2 mg/animal of MGT was approximately two- to three-fold higher than that of vehicle-control animals. Furthermore, in gpt delta transgenic mice, gpt mutant frequency (MF in the lungs of the group exposed to four consecutive doses of 0.2 mg MGT was significantly higher than in the control group. Mutation spectrum analysis showed that base substitutions were predominantly induced by MGT, among which G:C to A:T transition and G:C to T:A transversion were the most significant. To clarify the mechanism of mutation caused by MGT, we analyzed the formation of DNA adducts in the lungs of mice exposed to MGT. DNA was extracted from lungs of mice 3, 24, 72 and 168 h after intratracheal instillation of 0.2 mg/body of MGT, and digested enzymatically. 8-Oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG and lipid peroxide-related DNA adducts were quantified by stable isotope dilution liquid chromatography-mass spectrometry (LC-MS/MS. Compared with vehicle control, these DNA adduct levels were significantly increased in the MGT-treated mice. In addition to oxidative stress- and inflammation related-DNA adduct formations, inflammatory cell infiltration and focal granulomatous formations were also observed in the lungs of MGT-treated mice. Based on these findings, it is suggested that inflammatory responses are probably involved in the genotoxicity induced by MGT in the lungs of mice.

  7. Larval exposure to chlorpyrifos affects nutritional physiology and induces genotoxicity in silkworm Philosamia ricini (Lepidoptera: Saturnidae

    Directory of Open Access Journals (Sweden)

    Moni Kankana Kalita

    2016-11-01

    Full Text Available Chlorpyrifos is a most widely used organophosphate insecticide because of its cost effectiveness and degradable nature. However, this pesticide enters and contaminates the environment either by direct application, spray drifts or crop run off and shows adverse effect on the non-targeted organisms. Philosamia ricini (eri silkworm, one of the most exploited, domesticated and commercialized non mulberry silkworm is known for mass production of eri silk. The silkworm larvae get exposed to pesticide residues on the leaves of food plants. The present study investigates the effect of commercial formulation of chlorpyrifos (Pyrifos-20 EC on eri silkworm. Initially the LC50 value of chlorpyrifos was determined at 24 - 96 h and further experiments were carried out with sub lethal concentrations of the chlorpyrifos after 24 h of exposure period. The potential toxicity of chlorpyrifos was evaluated as a fuction of metabolism and nutritional physiology in 3rd, 4th and 5th instar larvae. Alteration in histoarchitecture of 5th instar eri silkworm gut exposed to sub lethal concentration of chlorpyrifos formulation was also studied. Chlorpyrifos induced genotoxicity in silkworm hemocytes was also investigated by single cell gel electrophoresis, micronuclei assay and apoptosis assay. Herein, LC50 values of chlorpyrifos were calculated as 3.83, 3.35, 2.68 and 2.35 mg/L at 24 h, 48 h, 72 h and 96 h respectively. A significant decrease in trehalose activity along with digestive enzyme activity was observed in chlorpyrifos affected groups (P < 0.05. Further, genotoxicity study revealed higher tail percentage, tail length and tail moment of the damage DNA in chlorpyrifos exposed groups (P < 0.001. Moreover, at 2.0 mg/L concentration, ~ 10 fold increases in tail length was observed as compared to the control. Results showed activation of caspase activity following 24 hr chlorpyrifos exposure (1.5 mg/L and 2.0 mg/L in a dose-dependent manner. Moreover, in control group

  8. Replication stress and oxidative damage contribute to aberrant constitutive activation of DNA damage signalling in human gliomas

    DEFF Research Database (Denmark)

    Bartkova, J; Hamerlik, P; Stockhausen, Marie;

    2010-01-01

    brain and grade II astrocytomas, despite the degree of DDR activation was higher in grade II tumors. Markers indicative of ongoing DNA replication stress (Chk1 activation, Rad17 phosphorylation, replication protein A foci and single-stranded DNA) were present in GBM cells under high- or low...... and indicate that replication stress, rather than oxidative stress, fuels the DNA damage signalling in early stages of astrocytoma development.......Malignant gliomas, the deadliest of brain neoplasms, show rampant genetic instability and resistance to genotoxic therapies, implicating potentially aberrant DNA damage response (DDR) in glioma pathogenesis and treatment failure. Here, we report on gross, aberrant constitutive activation of DNA...

  9. Necdin modulates proliferative cell survival of human cells in response to radiation-induced genotoxic stress

    Directory of Open Access Journals (Sweden)

    Lafontaine Julie

    2012-06-01

    Full Text Available Abstract Background The finite replicative lifespan of cells, termed cellular senescence, has been proposed as a protective mechanism against the proliferation of oncogenically damaged cells, that fuel cancer. This concept is further supported by the induction of premature senescence, a process which is activated when an oncogene is expressed in normal primary cells as well as following intense genotoxic stresses. Thus, deregulation of genes that control this process, like the tumor suppressor p53, may contribute to promoting cancer by allowing cells to bypass senescence. A better understanding of the genes that contribute to the establishment of senescence is therefore warranted. Necdin interacts with p53 and is also a p53 target gene, although the importance of Necdin in the p53 response is not clearly understood. Methods In this study, we first investigated Necdin protein expression during replicative senescence and premature senescence induced by gamma irradiation and by the overexpression of oncogenic RasV12. Gain and loss of function experiments were used to evaluate the contribution of Necdin during the senescence process. Results Necdin expression declined during replicative aging of IMR90 primary human fibroblasts or following induction of premature senescence. Decrease in Necdin expression seemed to be a consequence of the establishment of senescence since the depletion of Necdin in human cells did not induce a senescence-like growth arrest nor a flat morphology or SA-β-galactosidase activity normally associated with senescence. Similarly, overexpression of Necdin did not affect the life span of IMR90 cells. However, we demonstrate that in normal human cells, Necdin expression mimicked the effect of p53 inactivation by increasing radioresistance. Conclusion This result suggests that Necdin potentially attenuate p53 signaling in response to genotoxic stress in human cells and supports similar results describing an inhibitory function

  10. Genotoxicity testing of peptides: Folate deprivation as a marker of exaggerated pharmacology

    Energy Technology Data Exchange (ETDEWEB)

    Guérard, Melanie, E-mail: melanie.guerard@roche.com; Zeller, Andreas; Festag, Matthias; Schubert, Christine; Singer, Thomas; Müller, Lutz

    2014-09-15

    The incidence of micronucleated-cells is considered to be a marker of a genotoxic event and can be caused by direct- or indirect-DNA reactive mechanisms. In particular, small increases in the incidence of micronuclei, which are not associated with toxicity in the target tissue or any structurally altering properties of the compound, trigger the suspicion that an indirect mechanism could be at play. In a bone marrow micronucleus test of a synthetic peptide (a dual agonist of the GLP-1 and GIP receptors) that had been integrated into a regulatory 13-week repeat-dose toxicity study in the rat, small increases in the incidence of micronuclei had been observed, together with pronounced reductions in food intake and body weight gain. Because it is well established that folate plays a crucial role in maintaining genomic integrity and pronounced reductions in food intake and body weight gain were observed, folate levels were determined from plasma samples initially collected for toxicokinetic analytics. A dose-dependent decrease in plasma folate levels was evident after 4 weeks of treatment at the mid and high dose levels, persisted until the end of the treatment duration of 13-weeks and returned to baseline levels during the recovery period of 4 weeks. Based on these properties, and the fact that the compound tested (peptide) per se is not expected to reach the nucleus and cause DNA damage, the rationale is supported that the elevated incidence of micronucleated polychromatic erythrocytes is directly linked to the exaggerated pharmacology of the compound resulting in a decreased folate level. - Highlights: • A synthetic peptide has been evaluated for potential genotoxicity • Small increases in an integrated (13-weeks) micronucleus test were observed • Further, animals had a pronounced reductions in food intake and body weight gain • A dose-dependent decrease in plasma folate levels was evident from week 4 onwards • Elevated micronuclei-incidence due to the

  11. DNA damage checkpoint recovery and cancer development

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haiyong [First affiliated hospital, Zhejiang University, School of medicine, Cancer Center, 79 Qingchun Road, Hangzhou 310003 (China); Zhang, Xiaoshan [Department of Genetics, University of Texas M.D. Anderson Cancer Center, Department of Genetics Unit 1010, 1515 Holcombe Blvd. Houston, TX 77030 (United States); Teng, Lisong, E-mail: lsteng@zju.edu.cn [First affiliated hospital, Zhejiang University, School of medicine, Cancer Center, 79 Qingchun Road, Hangzhou 310003 (China); Legerski, Randy J., E-mail: rlegersk@mdanderson.org [Department of Genetics, University of Texas M.D. Anderson Cancer Center, Department of Genetics Unit 1010, 1515 Holcombe Blvd. Houston, TX 77030 (United States)

    2015-06-10

    Cell cycle checkpoints were initially presumed to function as a regulator of cell cycle machinery in response to different genotoxic stresses, and later found to play an important role in the process of tumorigenesis by acting as a guard against DNA over-replication. As a counterpart of checkpoint activation, the checkpoint recovery machinery is working in opposition, aiming to reverse the checkpoint activation and resume the normal cell cycle. The DNA damage response (DDR) and oncogene induced senescence (OIS) are frequently found in precancerous lesions, and believed to constitute a barrier to tumorigenesis, however, the DDR and OIS have been observed to be diminished in advanced cancers of most tissue origins. These findings suggest that when progressing from pre-neoplastic lesions to cancer, DNA damage checkpoint barriers are overridden. How the DDR checkpoint is bypassed in this process remains largely unknown. Activated cytokine and growth factor-signaling pathways were very recently shown to suppress the DDR and to promote uncontrolled cell proliferation in the context of oncovirus infection. In recent decades, data from cell line and tumor models showed that a group of checkpoint recovery proteins function in promoting tumor progression; data from patient samples also showed overexpression of checkpoint recovery proteins in human cancer tissues and a correlation with patients' poor prognosis. In this review, the known cell cycle checkpoint recovery proteins and their roles in DNA damage checkpoint recovery are reviewed, as well as their implications in cancer development. This review also provides insight into the mechanism by which the DDR suppresses oncogene-driven tumorigenesis and tumor progression. - Highlights: • DNA damage checkpoint works as a barrier to cancer initiation. • DDR machinary response to genotoxic and oncogenic stress in similar way. • Checkpoint recovery pathways provide active signaling in cell cycle control. • Checkpoint

  12. Genotoxicity of 2-bromo-3′-chloropropiophenone

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Fanxue; Yan, Jian; Li, Yan [Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079 (United States); Fu, Peter P. [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079 (United States); Fossom, Linda H.; Sood, Ramesh K.; Mans, Daniel J.; Chu, Pei-I [Center for Drug Evaluation and Research, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD 20993 (United States); Moore, Martha M. [Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079 (United States); Chen, Tao, E-mail: tao.chen@fda.hhs.gov [Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079 (United States)

    2013-07-15

    Impurities are present in any drug substance or drug product. They can be process-related impurities that are not completely removed during purification or are formed due to the degradation of the drug substance over the product shelf-life. Unlike the drug substance, impurities generally do not have beneficial effects and may present a risk without associated benefit. Therefore, their amount should be minimized. 2-Bromo-3′-chloropropiophenone (BCP) is an impurity of bupropion, a second-generation antidepressant and a smoking cessation aid. The United States Pharmacopeia recommends an acceptable level for BCP that is not more than 0.1% of the bupropion. Because exposure to genotoxic impurities even at low levels is of significant concern, it is important to determine whether or not BCP is genotoxic. Therefore, in this study the Ames test and the in vitro micronucleus assay were conducted to evaluate the genotoxicity of BCP. BCP was mutagenic with S9 metabolic activation, increasing the mutant frequencies in a concentration-dependent manner, up to 22- and 145-fold induction over the controls in Salmonella strains TA100 and TA1535, respectively. BCP was also positive in the in vitro micronucleus assay, resulting in up to 3.3- and 5.1-fold increase of micronucleus frequency for treatments in the absence and presence of S9, respectively; and 9.9- and 7.4-fold increase of aneuploidies without and with S9, respectively. The addition of N-acetyl-L-cysteine, an antioxidant, reduced the genotoxicity of BCP in both assays. Further studies showed that BCP treatment resulted in induction of reactive oxygen species (ROS) in the TK6 cells. The results suggest that BCP is mutagenic, clastogenic, and aneugenic, and that these activities are mediated via generation of reactive metabolites. - Highlights: • 2-Bromo-3′-chloropropiophenone is an impurity of bupropion. • BCP was positive in both the Ames test and the in vitro micronucleus assay. • It induced high frequencies of

  13. Evaluation of the genotoxic potential of 3-monochloropropane-1,2-diol (3-MCPD) and its metabolites, glycidol and beta-chlorolactic acid, using the single cell gel/comet assay.

    Science.gov (United States)

    El Ramy, R; Ould Elhkim, M; Lezmi, S; Poul, J M

    2007-01-01

    3-monochloropropane-1,2-diol (3-MCPD) is a member of a group of chemicals known as chloropropanols. It is found in many foods and food ingredients as a result of food processing. 3-MCPD is regarded as a rat carcinogen known to induce Leydig-cell and mammary gland tumours in males and kidney tumours in both genders. The aim of our study was to clarify the possible involvement of genotoxic mechanisms in 3-MCPD induced carcinogenicity at the target organ level. For that purpose, we evaluated DNA damages in selected target (kidneys and testes) and non-target (blood leukocytes, liver and bone marrow) male rat organs by the in vivo alkaline single cell gel electrophoresis (comet) assay, 3 and 24 h after 3-MCPD oral administration to Sprague-Dawley and Fisher 344 adult rats. 3-MCPD may be metabolised to a genotoxic intermediate, glycidol, whereas the predominant urinary metabolite in rats following 3-MCPD administration is beta-chlorolactic acid. Therefore, we also studied the DNA damaging effects of 3-MCPD and its metabolites, glycidol and beta-chlorolactic acid, in the in vitro comet assay on CHO cells. Our results show the absence of genotoxic potential of 3-MCPD in vivo in the target as well as in the non-target organs. Glycidol, the epoxide metabolite, induced DNA damages in CHO cells. beta-Chlorolactic acid, the main metabolite of 3-MCPD in rats, was shown to be devoid of DNA-damaging effects in vitro in mammalian cells.

  14. Endocycling cells do not apoptose in response to DNA rereplication genotoxic stress.

    Science.gov (United States)

    Mehrotra, Sonam; Maqbool, Shahina B; Kolpakas, Alexis; Murnen, Katherine; Calvi, Brian R

    2008-11-15

    Initiation of DNA replication at origins more than once per cell cycle results in rereplication and has been implicated in cancer. Here we use Drosophila to examine the checkpoint responses to rereplication in a developmental context. We find that increased Double-parked (Dup), the Drosophila ortholog of Cdt1, results in rereplication and DNA damage. In most cells, this rereplication triggers caspase activation and apoptotic cell death mediated by both p53-dependent and -independent pathways. Elevated Dup also caused DNA damage in endocycling cells, which switch to a G/S cycle during normal development, indicating that rereplication and the endocycling DNA reduplication program are distinct processes. Unexpectedly, however, endocycling cells do not apoptose regardless of tissue type. Our combined evidence suggests that endocycling apoptosis is repressed in part because proapoptotic gene promoters are silenced. Normal endocycling cells had DNA lesions near heterochromatin, which increased after rereplication, explaining why endocycling cells must constantly repress the genotoxic apoptotic response. Our results reveal a novel regulation of apoptosis in development and new insights into the little-understood endocycle. Similar mechanisms may operate during vertebrate development, with implications for cancer predisposition in certain tissues.

  15. Potential pulmonary effects of engineered carbon nanotubes: in vitro genotoxic effects.

    Science.gov (United States)

    Sargent, Linda M; Reynolds, Steven H; Castranova, Vincent

    2010-12-01

    The development of novel engineered nano-sized materials is a rapidly emerging technology with many applications in medicine and industry. In vitro and in vivo studies have suggested many deleterious effects of carbon nanotube exposure including granulomatous inflammation, release of cytosolic enzymes, pulmonary fibrosis, reactive oxygen damage, cellular atypia, DNA fragmentation, mutation and errors in chromosome number as well as mitotic spindle disruption. The physical properties of the carbon nanotubes make respiratory exposure to workers likely during the production or use of commercial products. Many of the investigations of the genotoxicity of carbon nanotubes have focused on reactive oxygen mediated DNA damage; however, the long thin tubular-shaped carbon nanotubes have a striking similarity to cellular microtubules. The similarity of carbon nanotubes to microtubules suggests a potential to interact with cellular biomolecules, such as the mitotic spindle, as well as the motor proteins that separate the chromosomes during cell division. Disruption of centrosomes and mitotic spindles would result in monopolar, tripolar, and quadrapolar divisions of chromosomes. The resulting aneuploidy is a key mechanism in the potential carcinogenicity of carbon nanotubes.

  16. Genotoxic and antigenotoxic activity of acerola (Malpighia glabra L.) extract in relation to the geographic origin.

    Science.gov (United States)

    Nunes, Roberta Da Silva; Kahl, Vivian Francília Silva; Sarmento, Merielen Da Silva; Richter, Marc François; Abin-Carriquiry, Juan Andres; Martinez, Marcela María; Ferraz, Alexandre De Barros Falcão; Da Silva, Juliana

    2013-10-01

    Malpighia glabra L, popularly known as acerola, is considered a functional fruit and therefore is taken to prevent disease or as adjuvant to treatment strategies, since the fruit is an undeniable source of vitamin C, carotenoids, and flavonoids. Acerola is a natural source of vitamin C, flavonoids, and carotenoids. Its chemical composition is affected by genetic uniformity of the orchards and environmental factors. Considering the extensive growth of the culture of acerola in Brazil as well as its widespread use, this study evaluates the genotoxic and antigenotoxic activity of acerola in relation to geographical origin using the comet assay in mice blood cells in vitro. No acerola samples showed potential to induce DNA damage, independently of origin. Also, for antigenotoxicity activity, only the acerola sample from São Paulo reduced DNA damage induced by hydrogen peroxide (by about 56%). The sample from Ceará showed good antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl assay, in agreement with its higher rutin, quercetin, and vitamin C levels. Additional studies with other treatment regimens are necessary to better understand the impact of the complex mixture of acerola on genomic stability.

  17. Engineering Deinococcus radiodurans into biosensor to monitor radioactivity and genotoxicity in environment

    Institute of Scientific and Technical Information of China (English)

    GAO GuanJun; FAN Lu; LU HuiMing; HUA YueJin

    2008-01-01

    Based on a genetically modified radioresistant bacteria Deinococcus radiodurans, we constructed a real time whole cell biosensor to monitor radioactivity and genotoxicity in highly radioactive environment. The enhanced green fluorescence protein (eGFP) was fused to the promoter of the crucial DNA damage-inducible recA gone from D. radiodurans, and the consequent DNA fragment (PrecA-egfp) carried by plasmid was introduced into D. radiodurans R1 strain to obtain the biosensor strain DRG300. This engineered strain can express eGFP protein and generate fluorescence in induction of the recA gone promoter. Based on the correlation between fluorescence intensity and protein expression level in live D. radiodurans cells, we discovered that the fluorescence induction of strain DRG300 responds in a remarkable dose-dependent manner when treated with DNA damage sources such as gamma radiation and mitomycin C. It is encouraging to find the widely detective range and high sensitivity of this reconstructed strain comparing with other whole cell biosensors in former reports. These results suggest that the strain DRG300 is a potential whole cell biosensor to construct a detective system to monitor the biological hazards of radioactive and toxic pollutants in environment in real time.

  18. Can the comet assay be used reliably to detect nanoparticle-induced genotoxicity?

    Science.gov (United States)

    Karlsson, Hanna L; Di Bucchianico, Sebastiano; Collins, Andrew R; Dusinska, Maria

    2015-03-01

    The comet assay is a sensitive method to detect DNA strand breaks as well as oxidatively damaged DNA at the level of single cells. Today the assay is commonly used in nano-genotoxicology. In this review we critically discuss possible interactions between nanoparticles (NPs) and the comet assay. Concerns for such interactions have arisen from the occasional observation of NPs in the "comet head", which implies that NPs may be present while the assay is being performed. This could give rise to false positive or false negative results, depending on the type of comet assay endpoint and NP. For most NPs, an interaction that substantially impacts the comet assay results is unlikely. For photocatalytically active NPs such as TiO2 , on the other hand, exposure to light containing UV can lead to increased DNA damage. Samples should therefore not be exposed to such light. By comparing studies in which both the comet assay and the micronucleus assay have been used, a good consistency between the assays was found in general (69%); consistency was even higher when excluding studies on TiO2 NPs (81%). The strong consistency between the comet and micronucleus assays for a range of different NPs-even though the two tests measure different endpoints-implies that both can be trusted in assessing the genotoxicity of NPs, and that both could be useful in a standard battery of test methods.

  19. Genotoxic biomonitoring of agricultural workers exposed to pesticides in the north of Sinaloa State, Mexico.

    Science.gov (United States)

    Martínez-Valenzuela, Carmen; Gómez-Arroyo, Sandra; Villalobos-Pietrini, Rafael; Waliszewski, Stefan; Calderón-Segura, María Elena; Félix-Gastélum, Rubén; Alvarez-Torres, Armando

    2009-11-01

    Genotoxic damage was evaluated in 70 agricultural workers, 25 women and 45 men, exposed to pesticides in Las Grullas, Ahome, Sinaloa, Mexico, with an average of 7 years of exposure. The effect was detected through the sister chromatid exchanges (SCE) in lymphocytes of peripheral blood and micronuclei (MN) and other nuclear anomalies (NA) in buccal exfoliated cells. Also, the influence on cellular proliferation kinetics (CPK) was studied by means of the replication index (RI) and the cytotoxic effect was examined with the mitotic index (MI). The non-exposed group consisted of 70 other persons, 21 women and 47 men from the city of Los Mochis, Sinaloa, Mexico. Significant differences between the exposed and the non-exposed groups were observed in SCE, CPK, MI, MN and NA. Analysis of variance revealed that age, gender, smoking and alcohol consumption did not have a significant effect on genetic damage. However, there was a correlation between exposure time to pesticides and SCE frequency. These results could have been due to the exposure of workers to pesticides containing different chemical compounds. This study afforded valuable data to estimate the possible risk to health associated with pesticide exposure.

  20. Radiation damage

    CERN Document Server

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  1. Genotoxicity evaluation and a primary risk assessment of organic pollutants in the drinking water sources of Nanjing, China

    Institute of Scientific and Technical Information of China (English)

    LI Yi-qiang; WU Yu-lin; CHEN Yuan-gao; KONG Zhi-ming

    2006-01-01

    An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In this study, the comet assay was conducted to investigate the genotoxicity to human body caused by organic concentrates in the drinking water sources of Nanjing City from Yangtze River of China, and health and ecology risk due to expose to these organic pollutants were evaluated with the multimedia environmental assessment system (MEAS). For all the water samples, they were collected from four different locations in the drinking water sourcr samples, es of Nanjing City. The results of the comet assay showed that all the organic concentrates from the water samples could induce different levels DNA damages on human peripheral blood lymphocytes, and a statistically significant difference (p<0.01) was observed compared with the solvent control, which demonstrated the genotoxicity was in existence.According to the ambient severity (AS) of individual compound, we had sorted out the main organic pollutants in the drinking water source of the four waterworks, and the results showed that there was some potential hazard to human body for all the source water,namely the total ambient severity (TAS) of health for each water source was more than 1. However, the TAS of ecology for each water source was less than 1, which indicated that it was safe to ecology. The results of this investigation demonstrate the application of the comet assay and the MEAS in aquatic environmental monitoring studies, and the comet assay found to be fast, sensitive, and suitable for genotoxicity monitoring programs of drinking water source.

  2. Correlation between the genotoxicity endpoints measured by two different genotoxicity assays: comet assay and CBMN assay

    OpenAIRE

    Carina Ladeira; Susana Viegas; Manuel C. Gomes

    2015-01-01

    The cytokinesis-block micronucleus cytome (CBMN) assay is a comprehensive system for measuring DNA damage; cytostasis and cytotoxicity-DNA damage events are scored specifically in once-divided binucleated cells. The endpoints possible to be measured are micronuclei (MN), a biomarker of chromosome breakage and/or whole chromosome loss, nucleoplasmic bridges (NPB), a biomarker of DNA misrepair and/or telomere end-fusions, and nuclear buds (NBUD), a biomarker of elimination of amplified DNA and/...

  3. Lesion simulating disease 1 and enhanced disease susceptibility 1 differentially regulate UV-C-induced photooxidative stress signalling and programmed cell death in Arabidopsis thaliana.

    Science.gov (United States)

    Wituszyńska, Weronika; Szechyńska-Hebda, Magdalena; Sobczak, Mirosław; Rusaczonek, Anna; Kozłowska-Makulska, Anna; Witoń, Damian; Karpiński, Stanisław

    2015-02-01

    As obligate photoautotrophs, plants are inevitably exposed to ultraviolet (UV) radiation. Because of stratospheric ozone depletion, UV has become more and more dangerous to the biosphere. Therefore, it is important to understand UV perception and signal transduction in plants. In the present study, we show that lesion simulating disease 1 (LSD1) and enhanced disease susceptibility 1 (EDS1) are antagonistic regulators of UV-C-induced programmed cell death (PCD) in Arabidopsis thaliana. This regulatory dependence is manifested by a complex deregulation of photosynthesis, reactive oxygen species homeostasis, antioxidative enzyme activity and UV-responsive genes expression. We also prove that a UV-C radiation episode triggers apoptotic-like morphological changes within the mesophyll cells. Interestingly, chloroplasts are the first organelles that show features of UV-C-induced damage, which may indicate their primary role in PCD development. Moreover, we show that Arabidopsis Bax inhibitor 1 (AtBI1), which has been described as a negative regulator of plant PCD, is involved in LSD1-dependent cell death in response to UV-C. Our results imply that LSD1 and EDS1 regulate processes extinguishing excessive energy, reactive oxygen species formation and subsequent PCD in response to different stresses related to impaired electron transport.

  4. p53 mutant human glioma cells are sensitive to UV-C-induced apoptosis due to impaired cyclobutane pyrimidine dimer removal.

    Science.gov (United States)

    Batista, Luis F Z; Roos, Wynand P; Kaina, Bernd; Menck, Carlos F M

    2009-02-01

    The p53 protein is a key regulator of cell responses to DNA damage, and it has been shown that it sensitizes glioma cells to the alkylating agent temozolomide by up-regulating the extrinsic apoptotic pathway, whereas it increases the resistance to chloroethylating agents, such as ACNU and BCNU, probably by enhancing the efficiency of DNA repair. However, because these agents induce a wide variety of distinct DNA lesions, the direct importance of DNA repair is hard to access. Here, it is shown that the induction of photoproducts by UV light (UV-C) significantly induces apoptosis in a p53-mutated glioma background. This is caused by a reduced level of photoproduct repair, resulting in the persistence of DNA lesions in p53-mutated glioma cells. UV-C-induced apoptosis in p53 mutant glioma cells is preceded by strong transcription and replication inhibition due to blockage by unrepaired photolesions. Moreover, the results indicate that UV-C-induced apoptosis of p53 mutant glioma cells is executed through the intrinsic apoptotic pathway, with Bcl-2 degradation and sustained Bax and Bak up-regulation. Collectively, the data indicate that unrepaired DNA lesions induce apoptosis in p53 mutant gliomas despite the resistance of these gliomas to temozolomide, suggesting that efficiency of treatment of p53 mutant gliomas might be higher with agents that induce the formation of DNA lesions whose global genomic repair is dependent on p53.

  5. Assessment of genotoxic potential of Tamra Bhasma (incinerated copper

    Directory of Open Access Journals (Sweden)

    Swapnil Y Chaudhari

    2015-01-01

    Full Text Available Introduction: The presence of metallic content in Ayurvedic drugs became an important burning issue in present days. The usefulness of Bhasmas (incinerated metals/minerals in therapeutics, their safety or toxicity is frequently being raised on different platforms. Considering this, there is a need to develop toxicity profiles of different metals/minerals. Tamra Bhasma (incinerated copper one such metallic formulation is widely used in cardiac and lipid disorders by Ayurvedic Physicians. The present study is aimed to evaluate the genotoxic potential of Tamra Bhasma. Materials and Methods: It was prepared as per classical guidelines and administered to Swiss albino mice for 14 consecutive days. Chromosomal aberration and sperm abnormality assay were studied. Results: All treated groups exhibited significant body weight gain in comparison to cyclophosphamide (CP group. Results revealed no structural deformity in above parameters in comparison to CP group. Conclusion: Reported data showed that both tested samples of Tamra Bhasma were not genotoxic and can be used safely.

  6. Genotoxicity of Euphorbia hirta: an Allium cepa assay.

    Science.gov (United States)

    Yuet Ping, Kwan; Darah, Ibrahim; Yusuf, Umi Kalsom; Yeng, Chen; Sasidharan, Sreenivasan

    2012-06-26

    The potential genotoxic effects of methanolic extracts of Euphorbia hirta which is commonly used in traditional medicine to treat a variety of diseased conditions including asthma, coughs, diarrhea and dysentery was investigated using Allium cepa assay. The extracts of 125, 250, 500 and 1,000 µg/mL were tested on root meristems of A. cepa. Ethylmethanesulfonate was used as positive control and distilled water was used as negative control. The result showed that mitotic index decreased as the concentrations of E. hirta extract increased. A dose-dependent increase of chromosome aberrations was also observed. Abnormalities scored were stickiness, c-mitosis, bridges and vagrant chromosomes. Micronucleated cells were also observed at interphase. Result of this study confirmed that the methanol extracts of E. hirta exerted significant genotoxic and mitodepressive effects at 1,000 µg/mL.

  7. Acetaminophen metabolism, cytotoxicity, and genotoxicity in rat primary hepatocyte cultures

    Energy Technology Data Exchange (ETDEWEB)

    Milam, K.M.; Byard, J.L.

    1985-06-30

    Acetaminophen (APAP) metabolism, cytotoxicity, and genotoxicity were measured in primary cultures of rat hepatocytes. Although 3 mM APAP caused a slight increase in cellular release of lactate dehydrogenase into the culture medium, cellular glutathione concentration (an index of APAP metabolism) was reduced by 50%. APAP at 7 mM was significantly more toxic to these hepatocytes and had a similar but more marked effect on glutathione concentrations. In spite of its cytotoxicity, neither dose of APAP stimulated DNA repair synthesis when monitored by the rate of incorporation of (/sup 3/H)thymidine into DNA following exposure to APAP. Thus, although APAP has been shown to be both hepato- and nephrotoxic in several in vivo and in vitro systems, the reactive toxic metabolite of APAP is not genotoxic in rat primary hepatocyte cultures.

  8. Tradescantia micronucleus test indicates genotoxic potential of traffic emissions in European cities

    DEFF Research Database (Denmark)

    Klumpp, A.; Ansel, W.; Klumpp, G.

    2006-01-01

    , the Tradescantia micronucleus (Trad-MCN) test was applied to examine the genotoxicity of urban air pollution. Cuttings of Tradescantia clone #4430 were exposed to ambient air at 65 monitoring sites in 10 conurbations employing a standardised methodology. The tests revealed an elevated genotoxic potential mainly...... is recommended in order to reduce the variability of results due to varying environmental conditions. The Tradescantia micronucleus test can be used to assess genotoxic potential at urban sites....

  9. Cytotoxicity and genotoxicity of phenazine in two human cell lines.

    Science.gov (United States)

    McGuigan, Claire F; Li, Xing-Fang

    2014-06-01

    Phenazine was recently identified as a drinking water disinfection byproduct (DBP), but little is known of its toxic effects. We examined in vitro cytotoxicity and genotoxicity of phenazine (1.9-123 μM) in HepG2 and T24 cell lines. Cytotoxicity was determined by an impedance-based real-time cell analysis instrument. The BrdU (5-bromo-2'-deoxyuridine) proliferation and MTT ((3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) viability assays were used to examine mechanisms of cytotoxicity. Genotoxicity was determined using the alkaline comet assay. Concentration-dependent cytotoxicity was observed in HepG2 cells, primarily due to an antiproliferative effect (BrdU 24 h IC50: 11 μM; 48 h IC50: 7.8 μM) observed as low as 1.9 μM. T24 cells experienced a minor antiproliferative effect (BrdU 24 h IC50: 47 μM; 48 h IC50: 17 μM). IC50 values for HepG2 proliferation and viability were 54-77% lower compared to T24 cells. In both cell lines, IC50 values for proliferation were 66-90% lower than those for viability. At phenazine concentrations producing equivalent cytotoxicity, HepG2 cells (1.9-30.8 μM) experienced no significant genotoxic effects, while T24 cells (7.7-123 μM) experienced significant genotoxicity at ⩾61.5 μM. While these effects were seen at phenazine concentrations above those found in disinfected water, the persistence of the antiproliferative effect and the differential toxicity in each cell line deserves further study.

  10. Genotoxicity of Euphorbia hirta: An Allium cepa Assay

    OpenAIRE

    Kwan Yuet Ping; Ibrahim Darah; Umi Kalsom Yusuf; Chen Yeng; Sreenivasan Sasidharan

    2012-01-01

    The potential genotoxic effects of methanolic extracts of Euphorbia hirta which is commonly used in traditional medicine to treat a variety of diseased conditions including asthma, coughs, diarrhea and dysentery was investigated using Allium cepa assay. The extracts of 125, 250, 500 and 1,000 µg/mL were tested on root meristems of A. cepa. Ethylmethanesulfonate was used as positive control and distilled water was used as negative ...

  11. Neoplastic transformation of breast epithelial cells by genotoxic stress

    OpenAIRE

    Raman Venu; Winnard Paul T; Botlagunta Mahendran

    2010-01-01

    Abstract Background Exposure to genotoxic stresses such as radiation and tobacco smoke can cause increased cancer incidence rate as reflected in an in depth meta-analysis of data for women and breast cancer incidence. Published reports have indicated that exposures to low dose radiation and tobacco smoke are factors that contribute to the development of breast cancer. However, there is a scarcity of information on the combinatorial effects of low dose radiation and tobacco smoke on formation ...

  12. Genotoxicity of organic extracts of house dust from Shanxi, China

    Energy Technology Data Exchange (ETDEWEB)

    Naufal, Z.; Zhou, G.D.; McDonald, T.; Li, Z.W.; Li, Z.; Donnelly, K.C. [Texas A& amp; M Health Science Center, College Station, TX (USA). School for Rural Public Health

    2007-07-01

    Indoor combustion of solid fuel such as coal may generate respirable particles containing polycyclic aromatic hydrocarbons (PAH) that may adhere to settled dust. Dust might therefore present a major source of PAH exposure in humans. This study evaluated the in vitro and in vivo genotoxicity of PAH mixtures extracted from house dust samples. Four dust samples (E1-4) were collected from houses in Shanxi, China, where coal is heavily used for heating and cooking. For comparison, a coal sample was also collected from one of the houses and included in the analyses. The samples were extracted with methylene chloride: acetone (95:5 v/v), dried, and redissolved in appropriate solvents for assessment in genotoxicity assays. Samples were evaluated for their ability to induce point mutations in bacteria and DNA adducts in vivo. DNA adduct levels were analyzed by nuclease P1-enhanced P-32-postlabeling. PAH were quantified using gas chromatography/mass spectrometry. Based on chemical analysis, sample E1 had the highest concentration by sampling area of benzo(a) pyrene (BaP) (181 {mu} g/m{sup 2}) and total PAH (10100 {mu} g/m{sup 2}). However, based on the microbial genotoxicity assay, sample E3, with the highest carcinogenic PAH/total PAH ratio (26%), produced the greatest number of revertants. In mice, administration of the extract of coal induced more adducts (9.81 adducts per 109 nucleotides) than dust extracts. The results of this study confirm the presence of genotoxic chemicals in residential dust. Inhalation of respirable particles containing similar mixtures of PAH represents a cancer risk for humans.

  13. DNA damage activates a spatially distinct late cytoplasmic cell-cycle checkpoint network controlled by MK2-mediated RNA stabilization

    DEFF Research Database (Denmark)

    Reinhardt, H Christian; Hasskamp, Pia; Schmedding, Ingolf

    2010-01-01

    Following genotoxic stress, cells activate a complex kinase-based signaling network to arrest the cell cycle and initiate DNA repair. p53-defective tumor cells rewire their checkpoint response and become dependent on the p38/MK2 pathway for survival after DNA damage, despite a functional ATR-Chk1...

  14. DNA Damage Activates a Spatially Distinct Late Cytoplasmic Cell-Cycle Checkpoint Network Controlled by MK2-Mediated RNA Stabilization

    NARCIS (Netherlands)

    Reinhardt, H. Christian; Hasskamp, Pia; Schmedding, Ingolf; Morandell, Sandra; van Vugt, Marcel A. T. M.; Wang, XiaoZhe; Linding, Rune; Ong, Shao-En; Weaver, David; Carr, Steven A.; Yaffe, Michael B.

    2010-01-01

    Following genotoxic stress, cells activate a complex kinase-based signaling network to arrest the cell cycle and initiate DNA repair. p53-defective tumor cells rewire their checkpoint response and become dependent on the p38/MK2 pathway for survival after DNA damage, despite a functional ATR-Chk1 pa

  15. Genotoxic effects of sodium nitrate in onion roots

    Directory of Open Access Journals (Sweden)

    Maria-Mihaela ANTOFIE

    2013-11-01

    Full Text Available The scope of this paper is to assess cyto- and genotoxic effects of sodium nitrate on Allium cepa root tips by using different concentrations (i.e. 0,1%; 1% and 5% for treating uniform healthy onion bulbs for three different periods of time: 6, 24 and 72 hours. In the end of the experiment the harvested root tips were prepared according to Feulgen’s squash technique using Schiff reagent and the investigations were realized according to Allium test. The cytotoxic and genotoxic effects of nitrate were investigated by calculating the mitotic index and observing all chromosomes’ complement alterations during the mitosis. The phase rate of cells undergoing mitosis is also studied. For microscopy investigations a Novex Holland B microscope with digital camera included was used. The cytogenetic analysis of nitrate effects revealed a strong decrease in the mitotic index which is more intense with the concentration and time of exposure. Moreover, this effect is associated in case of the variant treated with 5% sodium nitrate acting for more than 24 hours, with the appearance of genotoxic effects such as chromosomal alterations, highly condensed chromatin expression easily identified during mitosis stages, sticky chromosomes and chromosomal bridges and laggards.

  16. Molecular and cytogenetic assessment of Dipterygium glaucum genotoxicity

    Directory of Open Access Journals (Sweden)

    NADA H. ALTWATY

    2016-01-01

    Full Text Available ABSTRACT The aim of the present study is to assess the genotoxicity of Dipterygium glaucum grows widely in Saudi Arabia desert to produce safety herbal products. This work is considered the first and pioneer report so far due to the lack and poor evaluated reports of the plant species for their mutagensity, genotoxicity and cytogenetics effects. Cytogenetic effects of D. glaucum on mitotic in roots of Vicia faba showed reduction in mitotic activity using three extracts; water, ethanol and ethyl acetate. Chromosomal abnormalities were recorded that included stickiness of chromosomes, chromatin bridge, fragments, lagging chromosome and micronuclei. Protein bands and RAPD analyses of V. faba treated with three D. glaucum extracts revealed some newly induced proteins and DNA fragments and other disappeared. Chemical constitution of the plant species should be identified with their biological activities against human and animal cells like HeLa cancer cell line. We are recommending using additional genotoxicity tests and other toxicity tests on animal culture with different concentrations and also utilizing several drought and heat tolerant genes of the plant species in gene cloning to develop and improve other economical crop plants instead of using the species as oral herbal remedy

  17. Molecular and cytogenetic assessment of Dipterygium glaucum genotoxicity.

    Science.gov (United States)

    Altwaty, Nada H; El-Sayed, Osama E; Aly, Nariman A H; Baeshen, Mohamed N; Baeshen, Nabih A

    2016-01-01

    The aim of the present study is to assess the genotoxicity of Dipterygium glaucum grows widely in Saudi Arabia desert to produce safety herbal products. This work is considered the first and pioneer report so far due to the lack and poor evaluated reports of the plant species for their mutagensity, genotoxicity and cytogenetics effects. Cytogenetic effects of D. glaucum on mitotic in roots of Vicia faba showed reduction in mitotic activity using three extracts; water, ethanol and ethyl acetate. Chromosomal abnormalities were recorded that included stickiness of chromosomes, chromatin bridge, fragments, lagging chromosome and micronuclei. Protein bands and RAPD analyses of V. faba treated with three D. glaucum extracts revealed some newly induced proteins and DNA fragments and other disappeared. Chemical constitution of the plant species should be identified with their biological activities against human and animal cells like HeLa cancer cell line. We are recommending using additional genotoxicity tests and other toxicity tests on animal culture with different concentrations and also utilizing several drought and heat tolerant genes of the plant species in gene cloning to develop and improve other economical crop plants instead of using the species as oral herbal remedy.

  18. Genotoxicity of unmodified and organo-modified montmorillonite.

    Science.gov (United States)

    Sharma, Anoop Kumar; Schmidt, Bjørn; Frandsen, Henrik; Jacobsen, Nicklas Raun; Larsen, Erik Husfeldt; Binderup, Mona-Lise

    2010-07-19

    The natural clay mineral montmorillonite (Cloisite) Na+) and an organo-modified montmorillonite (Cloisite 30B) were investigated for genotoxic potential as crude suspensions and as suspensions filtrated through a 0.2-microm pore-size filter to remove particles above the nanometre range. Filtered and unfiltered water suspensions of both clays did not induce mutations in the Salmonella/microsome assay at concentrations up to 141microg/ml of the crude clay, using the tester strains TA98 and TA100. Filtered and unfiltered Cloisite) Na+ suspensions in culture medium did not induce DNA strand-breaks in Caco-2 cells after 24h of exposure, as tested in the alkaline comet assay. However, both the filtered and the unfiltered samples of Cloisite 30B induced DNA strand-breaks in a concentration-dependent manner and the two highest test concentrations produced statistically significantly different results from those seen with control samples (porgano-modified montmorillonite was caused by the organo-modifier. The detected organo-modifier mixture was synthesized and comet-assay results showed that the genotoxic potency of this synthesized organo-modifier was in the same order of magnitude at equimolar concentrations of organo-modifier in filtrated Cloisite) 30B suspensions, and could therefore at least partly explain the genotoxic effect of Cloisite) 30B.

  19. In vivo and in vitro genotoxicity studies of Semelil (ANGIPARSTM

    Directory of Open Access Journals (Sweden)

    Khorram Khorshid HR

    2008-04-01

    Full Text Available Semelil is a novel herbal-based compound formulated for treatment of bed sore and diabetic foot ulcer. The objective of the present preclinical study was to assess the mutagenicity and genotoxicity of Semelil in full compliance with the standard guidelines for testing chemicals. "nThe potential genotoxicity of Semelil, as part of the safety evaluation process was assessed in three different in vitro and in vivo tests, including bacterial reverse mutation (Ames test, mammalian bone marrow chromosomal aberration, and rodent dominant lethal assays. "nEffects of Semelil was clearly negative at different doses in the Ames test. No statistically significant differences were observed between the levels of chromosomal aberrations in bone marrow cells of mice from the experimental and control groups. The rate of post-implantation losses and thus, the number of lethal mutations in germ cells at different stages of spermatogenesis in male mice treated with a single dose of Semelil did not statistically exceed the control rate. While on the basis of these observations, Semelil can be considered genotoxically safe, further investigations using other bio-assays for mutagenicity studies are warranted.

  20. Safety pharmacology and genotoxicity evaluation of AVI-4658.

    Science.gov (United States)

    Sazani, Peter; Weller, Doreen L; Shrewsbury, Stephen B

    2010-01-01

    Duchenne muscular dystrophy (DMD) is caused by dystrophin gene mutations. Restoration of dystrophin by exon skipping was demonstrated with the phosphorodiamidate morpholino oligomers (PMO) class of splice-switching oligomers, in both mouse and dog disease models. The authors report the results of Good Laboratory Practice-compliant safety pharmacology and genotoxicity evaluations of AVI-4658, a PMO under clinical evaluation for DMD. In cynomolgus monkeys, no test article-related effects were seen on cardiovascular, respiratory, global neurological, renal, or liver parameters at the maximum feasible dose (320 mg/kg). Genotoxicity battery showed that AVI-4658 has no genotoxic potential at up to 5000 microg/mL in an in vitro mammalian chromosome aberration test and a bacterial reverse mutation assay. In the mouse bone marrow erythrocyte micronucleus test, a single intravenous injection up to 2000 mg/kg was generally well tolerated and resulted in no mutagenic potential. These results allowed initiation of systemic clinical trials in DMD patients in the United Kingdom.

  1. Genotoxicity risk assessment of diversely substituted quinolines using the SOS chromotest.

    Science.gov (United States)

    Duran, Leidy Tatiana Díaz; Rincón, Nathalia Olivar; Galvis, Carlos Eduardo Puerto; Kouznetsov, Vladimir V; Lorenzo, Jorge Luis Fuentes

    2015-03-01

    Quinolines are aromatic nitrogen compounds with wide therapeutic potential to treat parasitic and microbial diseases. In this study, the genotoxicity of quinoline, 4-methylquinoline, 4-nitroquinoline-1-oxide (4-NQO), and diversely functionalized quinoline derivatives and the influence of the substituents (functional groups and/or atoms) on their genotoxicity were tested using the SOS chromotest. Quinoline derivatives that induce genotoxicity by the formation of an enamine epoxide structure did not induce the SOS response in Escherichia coli PQ37 cells, with the exception of 4-methylquinoline that was weakly genotoxic. The chemical nature of the substitution (C-5 to C-8: hydroxyl, nitro, methyl, isopropyl, chlorine, fluorine, and iodine atoms; C-2: phenyl and 3,4-methylenedioxyphenyl rings) of quinoline skeleton did not significantly modify compound genotoxicities; however, C-2 substitution with α-, β-, or γ-pyridinyl groups removed 4-methylquinoline genotoxicity. On the other hand, 4-NQO derivatives whose genotoxic mechanism involves reduction of the C-4 nitro group were strong inducers of the SOS response. Methyl and nitrophenyl substituents at C-2 of 4-NQO core affected the genotoxic potency of this molecule. The relevance of these results is discussed in relation to the potential use of the substituted quinolines. The work showed the sensitivity of SOS chromotest for studying structure-genotoxicity relationships and bioassay-guided quinoline synthesis.

  2. In vitro immunotoxic and genotoxic activities of particles emitted from two different small-scale wood combustion appliances

    Science.gov (United States)

    Tapanainen, Maija; Jalava, Pasi I.; Mäki-Paakkanen, Jorma; Hakulinen, Pasi; Happo, Mikko S.; Lamberg, Heikki; Ruusunen, Jarno; Tissari, Jarkko; Nuutinen, Kati; Yli-Pirilä, Pasi; Hillamo, Risto; Salonen, Raimo O.; Jokiniemi, Jorma; Hirvonen, Maija-Riitta

    2011-12-01

    Residential wood combustion appliances emit large quantities of fine particles which are suspected to cause a substantial health burden worldwide. Wood combustion particles contain several potential health-damaging metals and carbon compounds such as polycyclic aromatic hydrocarbons (PAH), which may determine the toxic properties of the emitted particles. The aim of the present study was to characterize in vitro immunotoxicological and chemical properties of PM 1 ( Dp ≤ 1 μm) emitted from a pellet boiler and a conventional masonry heater. Mouse RAW264.7 macrophages were exposed for 24 h to different doses of the emission particles. Cytotoxicity, production of the proinflammatory cytokine TNF-α and the chemokine MIP-2, apoptosis and phases of the cell cycle as well as genotoxic activity were measured after the exposure. The type of wood combustion appliance had a significant effect on emissions and chemical composition of the particles. All the studied PM 1 samples induced cytotoxic, genotoxic and inflammatory responses in a dose-dependent manner. The particles emitted from the conventional masonry heater were 3-fold more potent inducers of programmed cell death and DNA damage than those emitted from the pellet boiler. Furthermore, the particulate samples that induced extensive DNA damage contained also large amounts of PAH compounds. Instead, significant differences between the studied appliances were not detected in measurements of inflammatory mediators, although the chemical composition of the combustion particles differed considerably from each other. In conclusion, the present results show that appliances representing different combustion technology have remarkable effects on physicochemical and associated toxicological and properties of wood combustion particles. The present data indicate that the particles emitted from incomplete combustion are toxicologically more potent than those emitted from more complete combustion processes.

  3. Exposure to runoff from coal-tar-sealed pavement induces genotoxicity and impairment of DNA repair capacity in the RTL-W1 fish liver cell line

    Energy Technology Data Exchange (ETDEWEB)

    Kienzler, Aude, E-mail: aude.kienzler@entpe.fr [Université de Lyon, UMR LEHNA 5023, USC INRA, ENTPE, rue Maurice Audin, Vaulx-en-Velin F-69518 (France); Mahler, Barbara J., E-mail: bjmahler@usgs.gov [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Van Metre, Peter C., E-mail: pcvanmet@usgs.gov [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Schweigert, Nathalie [Université de Lyon, UMR LEHNA 5023, USC INRA, ENTPE, rue Maurice Audin, Vaulx-en-Velin F-69518 (France); Devaux, Alain, E-mail: alain.devaux@entpe.fr [Université de Lyon, UMR LEHNA 5023, USC INRA, ENTPE, rue Maurice Audin, Vaulx-en-Velin F-69518 (France); Bony, Sylvie, E-mail: bony@entpe.fr [Université de Lyon, UMR LEHNA 5023, USC INRA, ENTPE, rue Maurice Audin, Vaulx-en-Velin F-69518 (France)

    2015-07-01

    Coal-tar-based (CTB) sealcoat, frequently applied to parking lots and driveways in North America, contains elevated concentrations of polycyclic aromatic hydrocarbons (PAHs) and related compounds. The RTL-W1 fish liver cell line was used to investigate two endpoints (genotoxicity and DNA-repair-capacity impairment) associated with exposure to runoff from asphalt pavement with CTB sealcoat or with an asphalt-based sealcoat hypothesized to contain about 7% CTB sealcoat (AS-blend). Genotoxic potential was assessed by the Formamido pyrimidine glycosylase (Fpg)-modified comet assay for 1:10 and 1:100 dilutions of runoff samples collected from 5 h to 36 d following sealcoat application. DNA-repair capacity was assessed by the base excision repair comet assay for 1:10 dilution of samples collected 26 h and 36 d following application. Both assays were run with and without co-exposure to ultraviolet-A radiation (UVA). With co-exposure to UVA, genotoxic effects were significant for both dilutions of CTB runoff for three of four sample times, and for some samples of AS-blend runoff. Base excision repair was significantly impaired for CTB runoff both with and without UVA exposure, and for AS-blend runoff only in the absence of UVA. This study is the first to investigate the effects of exposure to the complex mixture of chemicals in coal tar on DNA repair capacity. The results indicate that co-exposure to runoff from CT-sealcoated pavement and UVA as much as a month after sealcoat application has the potential to cause genotoxicity and impair DNA repair capacity. - Highlights: • Co-exposure to runoff from coal-tar-sealcoated pavement and UVA caused DNA damage. • Significant genotoxicity occurred with a 1:100 dilution of runoff. • Runoff collected up to 36 d following coal-tar-sealcoat application was genotoxic. • Exposure to runoff from sealed pavement impaired an important DNA repair pathway. • Repair capacity was impaired with a 1:10 dilution of runoff (1:100 not

  4. Lack of genotoxic effect of food dyes amaranth, sunset yellow and tartrazine and their metabolites in the gut micronucleus assay in mice.

    Science.gov (United States)

    Poul, Martine; Jarry, Gérard; Elhkim, Mostafa Ould; Poul, Jean-Michel

    2009-02-01

    The food dyes amaranth, sunset yellow and tartrazine were administered twice, at 24h intervals, by oral gavage to mice and assessed in the in vivo gut micronucleus test for genotoxic effects (frequency of micronucleated cells) and toxicity (apoptotic and mitotic cells). The concentrations of each compound and their main metabolites (sulfanilic acid and naphthionic acid) were measured in faeces during a 24-h period after single oral administrations of the food dyes to mice. Parent dye compounds and their main aromatic amine metabolites were detected in significant amounts in the environment of colonic cells. Acute oral exposure to food dye additives amaranth, sunset yellow and tartrazine did not induce genotoxic effect in the micronucleus gut assay in mice at doses up to 2000 mg/kg b.w. Food dyes administration increased the mitotic cells at all dose levels when compared to controls. These results suggest that the transient DNA damages previously observed in the colon of mice treated by amaranth and tartrazine by the in vivo comet assay [Sasaki, Y.F., Kawaguchi, S., Kamaya, A., Ohshita, M., Kabasawa, K., Iwama, K., Taniguchi, K., Tsuda, S., 2002. The comet assay with 8 mouse organs: results with 39 currently used food additives. Mutat. Res. 519, 103-119] are unable to be fixed in stable genotoxic lesions and might be partly explained by local cytotoxicity of the dyes.

  5. Effects of cerium dioxide nanoparticles in Oncorhynchus mykiss liver after an acute exposure: assessment of oxidative stress, genotoxicity and histological alterations

    Directory of Open Access Journals (Sweden)

    Ana Cristina Nunes

    2015-12-01

    Full Text Available At present cerium oxide nanoparticles (CeO2 NP have numerous applications ranging from industry to the household, leading to its wide distribution namely in the aquatic environment. The hereby study aimed to assess the toxic effects of CeO2 NPs in Oncorhynchus mykiss liver following an acute exposure (96h to three different concentrations (0.25, 2.5 and 25 mg/L in terms of the genotoxicity (comet assay, oxidative stress response (Catalase CAT; Glutathione S-Transferases GSTs; Thiobarbituric Acid Reactive Substances TBARS and histopathology. CeO2 NP exposure resulted in genotoxic damage in all exposure treatments, inhibition of CAT in the highest concentration and histopathological changes in all exposure concentrations with predominance of progressive and circulatory alterations. However TBARS and GSTs showed no significant differences comparatively to the control (unexposed group. The results suggest that CeO2 NP are able to cause genotoxicity, biochemical impairment and histological alterations in the liver of rainbow trout.

  6. Evaluation of the genotoxicity of Euterpe oleraceae Mart. (Arecaceae) fruit oil (açaí), in mammalian cells in vivo.

    Science.gov (United States)

    Marques, E S; Froder, J G; Carvalho, J C T; Rosa, P C P; Perazzo, F F; Maistro, E L

    2016-07-01

    E. oleracea is a tropical plant from the Amazon region, with its fruit used for food, and traditionally, as an antioxidant, anti-inflammatory, hypocholesterolemic, for atherosclerotic disease, and has anticancer properties. The oil of the fruit has antidiarrheic, anti-inflammatory and antinociceptive activities, but without genotoxicity evaluation. Therefore, the aim of this study was to evaluate the genotoxic potential of E. oleracea fruit oil (EOO), in rat cells. Male Wistar rats were treated with EOO by gavage at doses of 30, 100 and 300 mg/kg, for 14 days, within a 24 h interval. The DNA damage in the leukocytes, liver, bone marrow and testicular cells, was assessed by the comet assay, and the clastogenic/aneugenic effects in the bone marrow cells, by the micronucleus test. Our phytochemicals characterization of the EOO showed the presence of vanillic, palmitic, γ-linolenic, linoleic, oleic, cinnamic, caffeic, protocatechuic, ferulic, syringic acids, and flavonoids quercetin and kaempferol rutinoside as the main constituents. Both cytogenetic tests performed showed that EOO presented no significant genotoxic effects in the analyzed cells, at the three tested doses. These results indicate that, under our experimental conditions, E. oleracea fruit oil did not reveal genetic toxicity in rat cells.

  7. Differential effect of manool--a diterpene from Salvia officinalis, on genotoxicity induced by methyl methanesulfonate in V79 and HepG2 cells.

    Science.gov (United States)

    Nicolella, Heloiza Diniz; de Oliveira, Pollyanna Francielli; Munari, Carla Carolina; Costa, Gizela Faleiros Dias; Moreira, Monique Rodrigues; Veneziani, Rodrigo Cassio Sola; Tavares, Denise Crispim

    2014-10-01

    Salvia officinalis (sage) is a perennial woody subshrub native to the Mediterranean region that is commonly used as a condiment and as an anti-inflammatory, antioxidant and antimicrobial agent due to its biological activities. Manool is the most abundant micro-metabolite found in Salvia officinalis essential oils and extracts. We therefore decided to evaluate the cytotoxic, genotoxic and antigenotoxic potential of manool in Chinese hamster lung fibroblasts (V79) and human hepatoma cells (HepG2). Cytotoxicity was assessed by the colony-forming assay in V79 cells and toxic effects were observed at concentrations of up to 8.0 μg/mL. The micronucleus test was used to evaluate the genotoxicity and antigenotoxicity of manool in V79 and HepG2 cells at concentrations of 0.5-6.0 μg/mL and 0.5-8.0 μg/mL, respectively. For evaluation of antigenotoxicity, the concentrations of manool were combined with methyl methanesulfonate (MMS, 44 μg/mL). The results showed a significant increase in the frequency of micronuclei in cultures of both cell lines treated with the highest concentration tested, demonstrating a genotoxic effect. On the other hand, manool exhibited a protective effect against chromosome damage induced by MMS in HepG2 cells, but not in V79 cells. These data suggest that some manool metabolite may be responsible for the antigenotoxic effect observed in HepG2 cells.

  8. In vivo genotoxicity testing of the amnesic shellfish poison (domoic acid) in piscine erythrocytes using the micronucleus test and the comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Cavas, Tolga [Mersin University, Faculty of Sciences and Letters, Department of Biology, 33343 Mersin (Turkey)], E-mail: tcavas@mersin.edu.tr; Koenen, Serpil [Mersin University, Faculty of Sciences and Letters, Department of Biology, 33343 Mersin (Turkey)

    2008-11-11

    Domoic acid (DA) is a neurotoxic amino acid naturally produced in the marine environment by some diatom species belonging to the genus Pseudo-nitzschia. Although the neurotoxic properties of DA have been demonstrated, very little is known about in vivo genotoxicity of DA on aquatic organisms. In the present paper, an in vivo study on the genotoxic effects of domoic acid was carried out on a fish, Oreochromis niloticus, using the micronucleus test and the comet assay. The fish were exposed to three doses of domoic acid (1, 5 and 10 {mu}g/g body weight) by intracoelomic injections. Ethyl methane sulphonate at a single dose of 5 mg/l was used as positive control. Analysis of micronuclei, nuclear abnormalities and DNA damage were carried out on peripheral erythrocytes sampled 24, 48 and 72 h post-treatment. Our results revealed significant increases in the frequencies of micronuclei, nuclear abnormalities as well as DNA strand breaks and thus demonstrated the genotoxic potential of DA on fish.

  9. Assessment of genotoxicity and cytotoxicity of standardized aqueous extract from leaves ofErythroxylum cuneatum in human HepG2 and WRL68 cells line

    Institute of Scientific and Technical Information of China (English)

    RK Wesam; AN Ghanya; HH Mizaton; M ILham; A Aishah

    2013-01-01

    Objective:To investigate the cytotoxicity and the genotoxicity of standardized aqueous of dry leaves ofErythroxylum cuneatum(E. cuneatum) in humanHepG2 andWRL68 cells. Methods:The cytotoxicity ofE. cuneatum extract was evaluated by bothMTS andLDH assays. Genotoxicity study onE. cuneatum extract was assessed by the single cell gel electrophoresis (comet assay).The protective effect ofE. cuneatum against menadione-induced cytotoxicity was also investigated.Results:Results from this study showed thatE. cuneatum extract exhibited cytotoxic activities towards the cells withIC50 value of(125±12) and(125±14) μg/mL forHepG2 andWRL68 cells respectively, after72 h incubation period as determined byMTS assay.LDH leakage was detected at(251±19) and(199.5±12.0) μg/mL forHepG2 andWRL68 respectively. Genotoxicity study results showed that treatment withE. cuneatum up to1 mg/mLdid not cause obviousDNA damage inWRL68 andHepG2 cells.Addition ofE. cunaetum did not show significant protection towards menadione inWRL68 andHepG2Cells.Conclusions:E. cuneatum standardized aqueous extract might be developed in order to establish new pharmacological possibilities for its application.

  10. Genotoxic effect of radio marked lymphocytes using Tc-99m complexes; Efecto genotoxico del radiomarcado de linfocitos empleando complejos de Tc-99m

    Energy Technology Data Exchange (ETDEWEB)

    Pedraza L, M.; Ferro F, G.; Mendiola C, M.T.; Morales R, P. [Instituto nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The genotoxic effect of radio marked lymphocytes was evaluated using {sup 99m}-Tc-HMPAO and {sup 99m}-Tc- gentisic acid complexes. With the results of this work it is pretended to contribute to the knowledge of genetic and structural damages that provokes the radiation in the marked lymphocytes. The d, 1-HMPAO was synthesized in laboratory with a yielding of 30 %. The radiochemical purity of the complexes was greater than 85%. Mouse lymphocytes obtained of sanguineous volumes 2 ml were used. The radio marked efficiency of cells was 19.6 {+-} 6.4% and 25.6 {+-} 5.8% for {sup 99m}Tc-HMPAO and {sup 99m} Tc gentisic acid respectively. The genotoxic effect was evaluated using the technique of Unicellular Electrophoresis in Micro gel (Comet assay). The results showed that both {sup 99m} Tc complexes produce genotoxicity due to their capacity to penetrate cells, therefore the Auger and M internal conversion electrons place all their energy obtaining doses of Gray order. (Author)

  11. Genotoxic and hematological effects in children exposed to a chemical mixture in a petrochemical area in Mexico.

    Science.gov (United States)

    Pelallo-Martínez, Nadia Azenet; Batres-Esquivel, Lilia; Carrizales-Yáñez, Leticia; Díaz-Barriga, Fernando Martínez

    2014-07-01

    Children living in Coatzacoalcos, Veracruz, and in nearby surrounding areas are exposed to a mixture of pollutants from different sources. Previous studies in the area have reported genotoxic and haematotoxic compounds, such as lead (Pb), benzene, toluene, and polycyclic aromatic hydrocarbons (PAHs), in environmental and biological samples. The final toxic effects of these compounds are unknown because the toxic behaviour of each compound is modified when in a complex mixture. This is the first study on the exposure and effect of chemical mixtures on children who live near a petrochemical area. The aim of this study was to evaluate genotoxicity and haematological effects in children environmentally exposed to such mixtures and to determine whether the final effect was modified by the composition of the mixture composition. Biomarkers of exposure to Pb, benzene, toluene, and PAHs were quantified in urine and blood samples of 102 children. DNA damage was evaluated using comet assay, and haematological parameters were determined. Our results show that Pb and toluene did not surpass the exposure guidelines; the exposure was similar in all three localities (Allenede, Mundo Nuevo, and López Mateos). In contrast, exposure to PAHs was observed at three levels of exposure: low, medium, and high. The most severe effects of these mixtures were strictly related to coexposure to high levels of PAHs.

  12. Influence of ethanol-diesel blended fuels on diesel exhaust emissions and mutagenic and genotoxic activities of particulate extracts.

    Science.gov (United States)

    Song, Chong-Lin; Zhou, Ying-Chao; Huang, Rui-Jing; Wang, Yu-Qiu; Huang, Qi-Fei; Lü, Gang; Liu, Ke-Ming

    2007-10-22

    This study was aimed at evaluating the influence of ethanol addition on diesel exhaust emissions and the toxicity of particulate extracts. The experiments were conducted on a heavy-duty diesel engine and five fuels were used, namely: E0 (base diesel fuel), E5 (5%), E10 (10%), E15 (15%) and E20 (20%), respectively. The regulated emissions (THC, CO, NOx, PM) and polycyclic aromatic hydrocarbon (PAH) emissions were measured, and Ames test and Comet assay, respectively, were used to investigate the mutagenicity and genotoxicity of particulate extracts. From the point of exhaust emissions, the introduction of ethanol to diesel fuel could result in higher brake specific THC (BSTHC) and CO (BSCO) emissions and lower smoke emissions, while the effects on the brake specific NOx (BSNOx) and particulate matters (BSPM) were not obvious. The PAH emissions showed an increasing trend with a growth of ethanol content in the ethanol-diesel blends. As to the biotoxicity, E20 always had the highest brake specific revertants (BSR) in both TA98 and TA100 with or without metabolizing enzymes (S9), while the lowest BSR were found in E5 except that of TA98-S9. DNA damage data showed a lower genotoxic potency of E10 and E15 as a whole.

  13. Antifungal activity against Cryptococcus neoformans strains and genotoxicity assessment in human leukocyte cells of Euphorbia tirucalli L.

    Directory of Open Access Journals (Sweden)

    Luís Flávio Souza de Oliveira

    2014-12-01

    Full Text Available In the last times, focus on plant research has increased all over the world. Euphorbia tirucalli L., a plant known popularly as Aveloz, and originally used in Africa, has been drawing attention for its use in the United States and Latin America, both for use as an ornamental plant and as a medicinal plant. E. tirucalli L. is a member of the family Euphorbiaceae and contains many diterpenoids and triterpenoids, in particular phorbol esters, apparently the main constituent of this plant, which are assumed to be responsible for their activities in vivo and in vitro. The in vitro antifungal activities of Euphorbia tirucalli (L. against opportunistic yeasts were studied using microbroth dilution assay. The results showed that aqueous extract and latex preparation were effective against ten clinical strains of Cryptococcus neoformans in vitro (Latex and extract MIC range of 3.2 - > 411 µg/mL. Aiming the safe use in humans, the genotoxic effects of E. tirucalli were evaluated in human leukocytes cells. Our data show that both aqueous extract and latex preparation have no genotoxic effect in human leukocytes cells in vitro. Although the results cannot be extrapolated by itself for use in vivo, they suggest a good perspective for a therapeutic application in future. In conclusion, our results show that the aqueous extract and latex preparation from E. tirucalli L. are antifungal agents effectives against several strains of C. neoformans and do not provoke DNA damage in human leukocyte cells, considering the concentrations tested.

  14. Evaluation of the Phytotoxic and Genotoxic Potential of Pulp and Paper Mill Effluent Using Vigna radiata and Allium cepa

    Directory of Open Access Journals (Sweden)

    Izharul Haq

    2016-01-01

    Full Text Available Pulp and paper mill effluent induced phytotoxicity and genotoxicity in mung bean (Vigna radiata L. and root tip cells of onion (Allium cepa L. were investigated. Physicochemical characteristics such as electrical conductivity (EC, biological oxygen demand (BOD5, chemical oxygen demand (COD, and total phenols of the pulp and paper mill effluent were beyond the permissible limit specified for the discharge of effluent in inland water bodies. Compared to control plants, seedling exposed to 100% effluent concentration showed a reduction in root and shoot length and biomass by 65%, 67%, and 84%, respectively, after 5 days of treatment. A. cepa root tip cells exposed to effluent concentrations ranging from 25 to 100% v/v showed a significant decrease in mitotic index (MI from 32 to 11% with respect to control root tip cells (69% indicating effluent induced cytotoxicity. Further, the effluent induced DNA damage as evidenced by the presence of various chromosomal aberrations like stickiness, chromosome loss, anaphase bridge, c-mitosis, tripolar anaphase, vagrant chromosome, and telophase bridge and micronucleated and binucleated cell in A. cepa. Findings of the present study indicate that pulp and paper mill effluents may act as genotoxic and phytotoxic agents in plant model system.

  15. Protective effect of probiotic bacteria against cadmium-induced genotoxicity in rat hepatocytes in vivo and in vitro

    Directory of Open Access Journals (Sweden)

    Đurašević Siniša F.

    2012-01-01

    Full Text Available The protective effect of probiotic bacteria against cadmium (Cd-induced genotoxicity was studied in rat hepatocytes in vivo and in vitro. Male Wistar rats, Rattus norvegicus, were treated for five weeks with (i CdCl2 (70 ppm in the drinking water, (ii a mixture of lyophilized probiotic bacteria Lactobacillus rhamnosus, L. acidophilus and Bifido-bacterium longum (5×108 cfu/g of food, or (iii CdCl2 and probiotic bacteria. In addition, single cells obtained from the untreated rat liver were exposed to CdCl2 (70 ppm, probiotic bacteria (1.28 mg/ml, or CdCl2 and probiotic bacteria, for 15 min at 22°C in the dark. The level of Cd-induced DNA damage in hepatocytes was determined by the comet assay. The obtained results show that probiotic bacteria significantly reduced Cd-induced genotoxicity, both in vivo and in vitro (20% and 48%, respectively. Moreover, the toxicity of Cd to lactobacilli in the gastrointestinal tracts of rats was significantly decreased in the probiotic-treated animals. The binding of Cd2+ to probiotic bacteria was proposed as the most probable protection mechanism. [Acknowledgments. This research was financially supported by the Ministry of Education and Science of the Government of Serbia, projects No 172058 and 173023

  16. Genotoxicity of ferric oxide nanoparticles in Raphanus sativus: Deciphering the role of signaling factors, oxidative stress and cell death.

    Science.gov (United States)

    Saquib, Quaiser; Faisal, Mohammad; Alatar, Abdulrahman A; Al-Khedhairy, Abdulaziz A; Ahmed, Mukhtar; Ansari, Sabiha M; Alwathnani, Hend A; Okla, Mohammad K; Dwivedi, Sourabh; Musarrat, Javed; Praveen, Shelly; Khan, Shams T; Wahab, Rizwan; Siddiqui, Maqsood A; Ahmad, Javed

    2016-09-01

    We have studied the genotoxic and apoptotic potential of ferric oxide nanoparticles (Fe2O3-NPs) in Raphanus sativus (radish). Fe2O3-NPs retarded the root length and seed germination in radish. Ultrathin sections of treated roots showed subcellular localization of Fe2O3-NPs, along with the appearance of damaged mitochondria and excessive vacuolization. Flow cytometric analysis of Fe2O3-NPs (1.0mg/mL) treated groups exhibited 219.5%, 161%, 120.4% and 161.4% increase in intracellular reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), nitric oxide (NO) and Ca(2+) influx in radish protoplasts. A concentration dependent increase in the antioxidative enzymes glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (LPO) has been recorded. Comet assay showed a concentration dependent increase in deoxyribonucleic acid (DNA) strand breaks in Fe2O3-NPs treated groups. Cell cycle analysis revealed 88.4% of cells in sub-G1 apoptotic phase, suggesting cell death in Fe2O3-NPs (2.0mg/mL) treated group. Taking together, the genotoxicity induced by Fe2O3-NPs highlights the importance of environmental risk associated with improper disposal of nanoparticles (NPs) and radish can serve as a good indicator for measuring the phytotoxicity of NPs grown in NP-polluted environment.

  17. Genotoxic effect of polycyclic aromatic hydrocarbons in the metropolitan area of Porto Alegre, Brazil, evaluated by Helix aspersa (Mueller, 1774)

    Energy Technology Data Exchange (ETDEWEB)

    Ianistcki, M. [Laboratorio de Genetica Toxicologica, Department of Biology, ULBRA, Av. Farroupilha 8001, Pr. 14/Sala 218, Bairro Sao Jose, CEP 92425-900 Canoas, RS (Brazil); Dallarosa, J. [Laboratorio de Ecologia, UFRGS (Brazil); Sauer, C.; Teixeira, C.E. [Fundacao Estadual de Protecao Ambiental Henrique Luis Roessler, FEPAM, RS (Brazil); Silva, J. da, E-mail: juliana.silva@ulbra.b [Laboratorio de Genetica Toxicologica, Department of Biology, ULBRA, Av. Farroupilha 8001, Pr. 14/Sala 218, Bairro Sao Jose, CEP 92425-900 Canoas, RS (Brazil)

    2009-07-15

    The purpose of this study was to biomonitor metropolitan areas of Porto Alegre (Brazil) for PAHs associated with atmospheric particles and check their effects on the DNA of the land mollusk Helix aspersa. The sampling sites are located in an urban area with heavy traffic: (i) Canoas, (ii) Sapucaia do Sul, and (iii) FIERGS/Porto Alegre. The samples were collected during a continuous period of 24 hours during 15 days using Stacked Filter Units (SFU) on polycarbonate filters (two separated size fractions: PM{sub 10-2.5} and PM{sub <2.5}). The concentrations of 16 major PAHs were determined according to EPA. Comet assay on H. aspersa hemolymph cells was chosen for genotoxicity evaluation. This evaluation shows that, in general, the smaller PM-size fractions (PM{sub <2.5}) have the highest genotoxicity and contain higher concentrations of extractable organic matter. In addition, associations between chemical characteristics and PM carcinogenicity tend to be stronger for the smaller PM-size fractions. - DNA damage in H. aspersa exposed to atmospheric particulate in Metropolitan Area of Porto Alegre demonstrated association with PAHs in the fine filter (PM{sub <2.5}).

  18. Genotoxicity of Aflatoxin B1 and Ochratoxin A after simultaneous application of the in vivo micronucleus and comet assay.

    Science.gov (United States)

    Corcuera, Laura-Ana; Vettorazzi, Ariane; Arbillaga, Leire; Pérez, Noemí; Gil, Ana Gloria; Azqueta, Amaya; González-Peñas, Elena; García-Jalón, Jose Antonio; López de Cerain, Adela

    2015-02-01

    Aflatoxin B1 (AFB1) and Ochratoxin A (OTA) are genotoxic mycotoxins that can contaminate a variety of foodstuffs, the liver and the kidney being their target organs, respectively. The micronucleus (MN) assay (bone marrow) and the comet assay (liver and kidney) were performed simultaneously in F344 rats, treated with AFB1 (0.25 mg/kg b.w.), OTA (0.5 mg/kg b.w.) or both mycotoxins. After AFB1 treatment, histopathology and biochemistry analysis showed liver necrosis, focal inflammation and an increase in Alanine Aminotransferase and Aspartate Aminotransferase. OTA alone did not cause any alteration. The acute hepatotoxic effects caused by AFB1 were less pronounced in animals treated with both mycotoxins. With regard to the MN assay, after 24 h, positive results were obtained for AFB1 and negative results were obtained for OTA, although both toxins caused bone marrow toxicity. In the combined treatment, OTA reduced the toxicity and the number of MN produced by AFB1. In the comet assay, after 3 h, positive results were obtained for AFB1 in the liver and for OTA in the kidney. The combined treatment reduced DNA damage in the liver and had no influence in the kidney. Altogether, these results may be indicative of an antagonistic relationship regarding the genotoxicity of both mycotoxins.

  19. Protective effects of hesperidin against genotoxicity induced by {sup 99m}Tc-MIBI in human cultured lymphocyte cells

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinimehr, Seyed Jalal [Department of Radiopharmacy, Faculty of Pharmacy and Traditional and Complementary Medicine Research Center, Mazandaran University of Medical Sciences, Sari (Iran, Islamic Republic of)], E-mail: sjhosseinim@yahoo.com; Ahmadi, Amirhossein [Department of Radiopharmacy, Faculty of Pharmacy and Traditional and Complementary Medicine Research Center, Mazandaran University of Medical Sciences, Sari (Iran, Islamic Republic of); Beiki, Davood [Research Institute for Nuclear Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Habibi, Emran [Department of Radiopharmacy, Faculty of Pharmacy and Traditional and Complementary Medicine Research Center, Mazandaran University of Medical Sciences, Sari (Iran, Islamic Republic of); Mahmoudzadeh, Aziz [Laboratory of Cytogenetics, Novin Radiation Institute, Tehran (Iran, Islamic Republic of)

    2009-10-15

    Introduction: Radiopharmaceuticals have been widely used as nuclear tracers for myocardial perfusion imaging. The purpose of this study was to investigate the radioprotective effects of hesperidin as a flavonoid which protects against the genotoxic effects of {sup 99m}Tc-MIBI in human cultured lymphocytes. Methods: Whole blood samples from human volunteers were incubated with hesperidin at doses of 10, 50 and 100 {mu}mol. After 1 h of incubation, the lymphocytes were incubated with {sup 99m}Tc-MIBI (200 {mu}Ci/2 ml) for 3 h. The lymphocyte cultures were then mitogenically stimulated to allow for evaluation of the number of micronuclei in cytokinesis-blocked binucleated cells. Results: Incubation of lymphocytes with {sup 99m}Tc-MIBI at this high dose induces additional genotoxicity and shown by increases in micronuclei frequency in human lymphocytes. Hesperidin at these doses significantly reduced the micronuclei frequency in cultured lymphocytes. The maximum protective effect and greatest decrease in micronuclei frequency occurred when cultures were incubated with a 100-{mu}mol dose of 65% hesperidin. Conclusion: This study has important implications for patients undergoing nuclear medicine procedures. The results indicate a protective role for hesperidin against the genetic damage and side effects induced by radiopharmaceutical administration.

  20. Evaluation of Mango Byproduct Extracts as Antioxidant Against Pb-Acetate-Induced Oxidative Stress and Genotoxicity in Mice

    Directory of Open Access Journals (Sweden)

    Makawy Aida I. El

    2015-03-01

    Full Text Available The antioxidant and antiproliferative properties of mango by-products were investigated. This study was carried out to evaluate the protective role of mango peel or kernel defatted extracts against Pb-acetate adverse effects on oxidant/antioxidant status, liver dysfunction biomarkers, histopathological changes and genotoxicity in male mice. Total phenolic content and antioxidant activity of both extracts were evaluated. Two doses of both extracts (50 and 100 mg/kg were used to evaluate their role against the toxicity of Pb-acetate (500 ppm. Mice given mango extracts with Pb-acetate had significantly lower plasma MDA, AST and ALT and higher glutathione than mice given Pb-acetate alone. Mango extracts prevented the histopathological changes in liver induced by Pb-acetate and decreased the cytotoxicity of lead by increasing the ratio of PCE/NCE. Mango extract treatment reduced the DNA damage induced by Pb-acetate in liver as demonstrated by a reduction in micronuclei and decrease in tail length, tail DNA% and Olive tail moment. It can be concluded that mango by-product extracts have potential to protect from oxidative stress and genotoxicity of lead.

  1. Determination of TiO2, ZrO2, and Al2O3 nanoparticles on genotoxic responses in human peripheral blood lymphocytes and cultured embyronic kidney cells.

    Science.gov (United States)

    Demir, Eşref; Burgucu, Durmuş; Turna, Fatma; Aksakal, Sezgin; Kaya, Bülent

    2013-01-01

    In this study a genotoxic evaluation of titanium dioxide (TiO2, 2.3 nm), zirconium oxide (ZrO2, 6 nm), aluminum oxide (Al2O3, 16.7 nm) nanoparticles (NP) and their ionic forms was conducted using human peripheral blood lymphocytes and cultured human embryonic kidney (HEK293) cells by means of a modified alkaline comet assay with/without the formamidopyrimidine-DNA glycosylase (Fpg) and endonuclease III (Endo III) enzymes. Modifications to the comet assay by using lesion-specific endonucleases, such as Endo III and Fpg, detect DNA bases with oxidative damage. Both human peripheral blood lymphocytes and cultured embryonic kidney cells were incubated with TiO2, ZrO2, or Al2O3 NP at concentrations of 1, 10, or 100 μg/ml. Our results showed no significant induction in DNA damage by the comet assay with/without the Endo III and Fpg enzymes at all concentrations of ZrO2 and Al2O3. In the case of TiO2 NP only the highest concentration of 100 μg/ml significantly induced a genotoxic response. Data thus indicate that both ZrO2 and Al2O3 NP were not genotoxic in our system and in the case of TiO2 the lowest-observed-adverse-effect level (LOAEL) for genotoxicity was 100 μg/ml. Evidence indicates that these metallic NP are considered safe in light of the fact that no genotoxicity was noted with ZrO2 and Al2O3 and that the highest TiO2 concentration is not environmentally relevant.

  2. Genotoxicity, potential cytotoxicity and cell uptake of titanium dioxide nanoparticles in the marine fish Trachinotus carolinus (Linnaeus, 1766)

    Energy Technology Data Exchange (ETDEWEB)

    Vignardi, Caroline P., E-mail: carolpatvig@usp.br [Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça do Oceanogáfico 191, Cidade Universitária, Butantã, São Paulo, SP 05508900 (Brazil); Hasue, Fabio M., E-mail: humbigutis@gmail.com [Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça do Oceanogáfico 191, Cidade Universitária, Butantã, São Paulo, SP 05508900 (Brazil); Sartório, Priscila V., E-mail: pri.sartorio@gmail.com [Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça do Oceanogáfico 191, Cidade Universitária, Butantã, São Paulo, SP 05508900 (Brazil); Cardoso, Caroline M., E-mail: camargonato@gmail.com [Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, Praça do Oceanogáfico 191, Cidade Universitária, Butantã, São Paulo, SP 05508900 (Brazil); Machado, Alex S.D., E-mail: mamiferomarinho@gmail.com [Faculty of Veterinary Medicine, Integrated College North of Minas Osmane Barbosa Avenue, 11111, JK, Montes Claros, MG 39404006 (Brazil); and others

    2015-01-15

    Highlights: • TiO{sub 2}–NP cytogenotoxicity and cell uptake in marine fish was studied. • TiO{sub 2}–NP suspension was in primary particle, agglomerated and aggregated form. • TiO{sub 2}–NP genotoxicity was time/dose dependent and may induce cell uptake. • Methodology proved to be efficient for evaluating the toxic effect of TiO{sub 2}–NP. - Abstract: Nanoparticles have physicochemical characteristics that make them useful in areas such as science, technology, medicine and in products of everyday use. Recently the manufacture and variety of these products has grown rapidly, raising concerns about their impact on human health and the environment. Adverse effects of exposure to nanoparticles have been reported for both terrestrial and aquatic organisms, but the toxic effects of the substances on marine organisms remain poorly understood. The main aim of this study was to evaluate the genotoxicity of TiO{sub 2}–NP in the marine fish Trachinotus carolinus, through cytogenotoxic methods. The fish received two different doses of 1.5 μg and 3.0 μg–TiO{sub 2}–NP g{sup −1} by intraperitoneal injection. Blood samples were collected to analyze erythrocyte viability using the Trypan Blue exclusion test, comet assay (pH > 13), micronucleus (MN) and other erythrocyte nuclear abnormalities (ENA) 24, 48 and 72 h after injection. The possible cell uptake of TiO{sub 2}–NP in fish injected with the higher dose was investigated after 72 h using transmission electron microscopy (TEM). The results showed that TiO{sub 2}–NP is genotoxic and potentially cytotoxic for this species, causing DNA damage, inducing the formation of MN and other ENA, and decreasing erythrocyte viability. TEM examination revealed that cell uptake of TiO{sub 2}–NP was mainly in the kidney, liver, gills and to a lesser degree in muscle. To the extent of the authors’ knowledge, this is the first in vivo study of genotoxicity and other effects of TiO{sub 2}–NP in a marine fish.

  3. DNA Damage Following Pulmonary Exposure by Instillation to Low Doses of Carbon Black (Printex 90) Nanoparticles in Mice

    DEFF Research Database (Denmark)

    Kyjovska, Zdenka O.; Jacobsen, Nicklas R.; Saber, Anne T.;

    2015-01-01

    of 0.67, 2, 6, and 162 mu g Printex 90 NPCB and vehicle. Cellular composition and protein concentration was evaluated in BAL fluid as markers of inflammatory response and cell damage. DNA strand breaks in BAL cells, lung, and liver tissue were assessed using the alkaline comet assay. The pulmonary......We previously observed genotoxic effects of carbon black nanoparticles at low doses relative to the Danish Occupational Exposure Limit (3.5 mg/m3). Furthermore, DNA damage occurred in broncho-alveolar lavage (BAL) cells in the absence of inflammation, indicating that inflammation is not required...... the comet assay. We interpret the increased DNA strand breaks occurring following these low exposure doses of NPCB as DNA damage caused by primary genotoxicity in the absence of substantial inflammation, cell damage, and acute phase response. Environ. Mol. Mutagen. 56:41-49, 2015. (c) 2014 The Authors...

  4. Application of the SOS/umu test and high-content in vitro micronucleus test to determine genotoxicity and cytotoxicity of nine benzothiazoles.

    Science.gov (United States)

    Ye, Yan; Weiwei, Jiang; Na, Li; Mei, Ma; Kaifeng, Rao; Zijian, Wang

    2014-12-01

    Benzothiazole and benzothiazole derivatives (BTs) have been detected in various environmental matrices as well as in human beings, but little is currently available regarding their toxicities. In our study, genotoxicities of nine BTs (benzothiazole [BT], 2-chlorobenzothiazole [CBT], 2-bromobenzothiazole [BrBT], 2-fluorobenzothiazole [FBT], 2-methylbenzothiazole [MeBT], 2-mercaptobenzothiazole [MBT], 2-aminobenzothiazole [ABT], 2-hydroxy-benzothiazole [OHBT] and 2-methythiobenzothiazole [MTBT]) are comprehensively evaluated by the SOS/umu test using the bacterial Salmonella typhimurium TA1535/pSK1002 for DNA-damaging effect and the high content in vitro micronucleus test using two human carcinoma cells (MGC-803 and A549) for chromosome-damaging effect. The cytotoxicity of BTs on both bacteria and two human cells was also evaluated. Except for the cytotoxic effect of MBT on MGC-803 and A549, the other tested BTs showed more than 50% cytotoxicity at their highest concentrations in a dose-dependent manner, and their LC50s ranged from 19 (MBT in bacteria) to 270 mg l(-1) (CBT in A549). Activation and inactivation were observed for specific BTs after metabolism. On the other hand, no evidence of genotoxicity was obtained for BT, FBT and MBT, and DNA damage was induced by ABT, OHBT, BrBT and MTBT in MGC-803, by MeBT in A549 and by CBT in both cells. Through quantitative structure-activity relationship analysis, two structure alerts for chemical genotoxicity, including heterocyclic amine and hacceptor-path3-hacceptor are present in ABT and OHBT respectively; however, the underlying mechanisms still need further evaluation.

  5. Genotoxic effect of substituted phenoxyacetic acids.

    Science.gov (United States)

    Venkov, P; Topashka-Ancheva, M; Georgieva, M; Alexieva, V; Karanov, E

    2000-11-01

    The potential toxic and mutagenic action of 2,4-dichlorophenoxyacetic acid has been studied in different test systems, and the obtained results range from increased chromosomal damage to no effect at all. We reexamined the effect of this herbicide by simultaneous using three tests based on yeast, transformed hematopoietic, and mouse bone marrow cells. The results obtained demonstrated that 2,4-dichlorophenoxyacetic acid has cytotoxic and mutagenic effects. The positive response of yeast and transformed hematopoietic cells was verified in kinetics and dose-response experiments. The analysis of metaphase chromosomes indicated a statistically proved induction of breaks, deletions, and exchanges after the intraperitoneal administration of 2,4-dichlorophenoxyacetic acid in mice. The study of phenoxyacetic acid and its differently chlorinated derivatives showed that cytotoxicity and mutagenicity are induced by chlorine atoms at position 2 and/or 4 in the benzene ring. The mutagenic effect was abolished by introduction of a third chlorine atom at position 5. Thus 2,4,5-trichlorophenoxyacetic acid was found to have very weak, if any mutagenic effect; however, the herbicide preserved its toxic effect.

  6. Testing the genotoxicity of some perfumes with high diethylphthalate (DEP levels using comet assay

    Directory of Open Access Journals (Sweden)

    Iman Al-Saleh

    2015-05-01

    Full Text Available The presence of phthalates in perfumes has gained recently some attention since these chemicals are added sometimes intentionally as a fixative. Our previous study tested 47 branded perfumes sold in Saudi market and found 68% of tested samples had diethylphthalate (DEP, above reported threshold limit of 1 ppm. Of these phthalates, DEP was found to have the highest mean value (1621.63 ppm. These results enticed us to test the potential genotoxicity of 7 brands in which their DEP contents were in the range of 1.06 ppm to 23649.3 ppm in human TK-6 cells using single cell gel electrophoresis assay (comet assay. Cells were exposed to 400 µl perfume for 2 hrs, at room temperature. Tail moment was (TM used as a metric measure for DNA damage and 25 cells per sample were determined by image analysis software. Four perfumes with DEP above 40 ppm produced significant DNA damage in TK-6 cells with TM of 54.27 ± 1.04, n=500 compare to the other 3 perfumes with DEP < 2 ppm (21.94 ± 1.09, n=300, untreated cells (2.99 ± 0.17, n=250 and cells induced with ethanol (33.76 ± 1.4, n=75 or methanol (23.82 ± 1.84, n=100 which are the vehicles used in perfume's preparations. The results suggest that DEP in perfumes might be one of the ingredients that provoked DNA damage; however, further investigation is required confirming our observation.

  7. Titanium dioxide nanoparticles induce genotoxicity but not mutagenicity in golden mussel Limnoperna fortunei.

    Science.gov (United States)

    Girardello, Francine; Custódio Leite, Camila; Vianna Villela, Izabel; da Silva Machado, Miriana; Luiz Mendes Juchem, André; Roesch-Ely, Mariana; Neves Fernandes, Andreia; Salvador, Mirian; Antonio Pêgas Henriques, João

    2016-01-01

    The widespread use of titanium dioxide nanoparticles (TiO2-NP) in consumer products is the cause of its appearance in wastewater and effluents, reaching the aquatic environment. The evaluation of the biological impact of TiO2-NP and the need to understand its ecotoxicological impact to the aquatic ecosystem are of major concern. Bivalve mollusks may represent a target group for nanoparticle toxicity. Limnoperna fortunei (golden mussel), a freshwater bivalve organism that has been employed in biomonitoring environmental conditions. Comet assay, micronucleus test and oxidative damage to lipids and proteins were performed after the golden mussel was exposed to TiO2-NP (1, 5, 10 and 50μgmL(-1)). The results demonstrate that TiO2-NP can damage the DNA of haemocytes after 2h of exposure and the genotoxic activity significantly increased after 4h exposure to TiO2-NP, at all the TiO2-NP concentrations. TiO2-NP was ineffective in causing mutagenicity in the haemolymph cells of golden mussel. The increase in the lipid peroxidation levels and carbonyl proteins after the exposure to TiO2-NP indicates the induction of oxidative stress at 2h exposure with similar results to all TiO2-NP concentrations, but these effects did not occur at 4h exposure. These results demonstrated that, although TiO2-NP is not mutagenic to golden mussel, it does induce DNA damage and oxidative stress in these organisms.

  8. Study on the Cytotoxic, Genotoxic and Clastogenic Potential of Attalea phalerata Mart. ex Spreng. Oil Pulp In Vitro and In Vivo Experimental Models.

    Science.gov (United States)

    Freitas de Lima, Fernando; Lima Tolouei Menegati, Sara Emilia; Karenina Traesel, Giseli; Souza de Araújo, Flávio Henrique; Honaiser Lescano, Caroline; Moraes Peixoto, Sara; Mao Silva, Felipe Ariel; Heredia Vieira, Silvia Cristina; do Carmo Vieira, Maria; Oesterreich, Silvia Aparecida

    2016-01-01

    Attalea phalerata Mart. ex Spreng. (Arecaceae), popularly known as "bacuri", is used in Brazilian folk medicine. Its oil is used orally to relieve pulmonary congestion and joint pain. In topical applications, it is applied as an effective hair tonic and anti-dandruff. The in natura pulp and its nuts are used as food because of its nutritional value. Despite its use in folk medicine, there is a lack of data regarding its in vivo/in vitro cytotoxic/genotoxic and clastogenic effects. Therefore, in this study, we evaluated the cytotoxic, genotoxic and clastogenic effects of Attalea phalerata Mart. ex Spreng. oil (APMO) in vitro and in vivo. For the analysis of cytotoxic potential, the Artemia salina and MTT (3-(4,5-dimethizzol-zyl)-2,5-diphenyltetrazolium bromide) assays were performed. Possible cytotoxic, genotoxic and clastogenic effects of APMO intake were determined by performing the comet and micronucleus assays. Male and female Wistar rats were orally treated with doses of 125, 250, 500 or 1000 mg.kg-1 of the APMO daily for 28 consecutive days (four weeks). The results showed that the APMO did not induce cell death in the experiments of Artemia salina and MTT, indicating that it has no cytotoxicity. The APMO did not cause significant damage to the DNA of the rats in the four doses used when compared to the negative control group (saline + Tween® 80). The APMO did not present any significant increase in micronucleated polychromatic erythrocytes (MNPCEs) for the four tested doses. When compared to the positive control group, all groups (comet and micronucleus tests) were statistically different. These data suggest that the administration of Attalea phalerata Mart oil. ex Spreng does not cause cytotoxicity, genotoxicity and clastogenicity in experimental models in vitro and in vivo following oral administration in this study.

  9. Study on the Cytotoxic, Genotoxic and Clastogenic Potential of Attalea phalerata Mart. ex Spreng. Oil Pulp In Vitro and In Vivo Experimental Models

    Science.gov (United States)

    Lima Tolouei Menegati, Sara Emilia; Karenina Traesel, Giseli; Souza de Araújo, Flávio Henrique; Honaiser Lescano, Caroline; Moraes Peixoto, Sara; Mao Silva, Felipe Ariel; Heredia Vieira, Silvia Cristina; do Carmo Vieira, Maria; Oesterreich, Silvia Aparecida

    2016-01-01

    Attalea phalerata Mart. ex Spreng. (Arecaceae), popularly known as “bacuri”, is used in Brazilian folk medicine. Its oil is used orally to relieve pulmonary congestion and joint pain. In topical applications, it is applied as an effective hair tonic and anti-dandruff. The in natura pulp and its nuts are used as food because of its nutritional value. Despite its use in folk medicine, there is a lack of data regarding its in vivo/in vitro cytotoxic/genotoxic and clastogenic effects. Therefore, in this study, we evaluated the cytotoxic, genotoxic and clastogenic effects of Attalea phalerata Mart. ex Spreng. oil (APMO) in vitro and in vivo. For the analysis of cytotoxic potential, the Artemia salina and MTT (3-(4,5-dimethizzol-zyl)-2,5-diphenyltetrazolium bromide) assays were performed. Possible cytotoxic, genotoxic and clastogenic effects of APMO intake were determined by performing the comet and micronucleus assays. Male and female Wistar rats were orally treated with doses of 125, 250, 500 or 1000 mg.kg-1 of the APMO daily for 28 consecutive days (four weeks). The results showed that the APMO did not induce cell death in the experiments of Artemia salina and MTT, indicating that it has no cytotoxicity. The APMO did not cause significant damage to the DNA of the rats in the four doses used when compared to the negative control group (saline + Tween® 80). The APMO did not present any significant increase in micronucleated polychromatic erythrocytes (MNPCEs) for the four tested doses. When compared to the positive control group, all groups (comet and micronucleus tests) were statistically different. These data suggest that the administration of Attalea phalerata Mart oil. ex Spreng does not cause cytotoxicity, genotoxicity and clastogenicity in experimental models in vitro and in vivo following oral administration in this study. PMID:27764219

  10. In vitro evaluation of the cyto-genotoxic potential of Ruthenium(II) SCAR complexes: a promising class of antituberculosis agents.

    Science.gov (United States)

    De Grandis, Rone Aparecido; Resende, Flávia Aparecida; da Silva, Monize Martins; Pavan, Fernando Rogério; Batista, Alzir Azevedo; Varanda, Elia