1
|
Fludioxonil, a phenylpyrrol pesticide, induces Cytoskeleton disruption, DNA damage and apoptosis via oxidative stress on rat glioma cells. Food Chem Toxicol 2022; 170:113464. [DOI: 10.1016/j.fct.2022.113464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/22/2022] [Accepted: 10/06/2022] [Indexed: 11/05/2022]
|
2
|
Schmidt SBI, Rodríguez-Rojas A, Rolff J, Schreiber F. Biocides used as material preservatives modify rates of de novo mutation and horizontal gene transfer in bacteria. JOURNAL OF HAZARDOUS MATERIALS 2022; 437:129280. [PMID: 35714537 DOI: 10.1016/j.jhazmat.2022.129280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 05/20/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Antimicrobial resistance (AMR) is a global health problem with the environment being an important compartment for the evolution and transmission of AMR. Previous studies showed that de-novo mutagenesis and horizontal gene transfer (HGT) by conjugation or transformation - important processes underlying resistance evolution and spread - are affected by antibiotics, metals and pesticides. However, natural microbial communities are also frequently exposed to biocides used as material preservatives, but it is unknown if these substances induce mutagenesis and HGT. Here, we show that active substances used in material preservatives can increase rates of mutation and conjugation in a species- and substance-dependent manner, while rates of transformation are not increased. The bisbiguanide chlorhexidine digluconate, the quaternary ammonium compound didecyldimethylammonium chloride, the metal copper, the pyrethroid-insecticide permethrin, and the azole-fungicide propiconazole increase mutation rates in Escherichia coli, whereas no increases were identified for Bacillus subtilis and Acinetobacter baylyi. Benzalkonium chloride, chlorhexidine and permethrin increased conjugation in E. coli. Moreover, our results show a connection between the RpoS-mediated general stress and the RecA-linked SOS response with increased rates of mutation and conjugation, but not for all biocides. Taken together, our data show the importance of assessing the contribution of material preservatives on AMR evolution and spread.
Collapse
Affiliation(s)
- Selina B I Schmidt
- Division of Biodeterioration and Reference Organisms (4.1), Department of Materials and the Environment, Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| | - Alexandro Rodríguez-Rojas
- Evolutionary Biology, Institute of Biology, Freie Universität Berlin, Königin-Luise-Straße 1-3, 14195 Berlin, Germany; Internal Medicine - Vetmeduni Vienna, Veterinärplatz 1, 1210 Vienna, Austria.
| | - Jens Rolff
- Evolutionary Biology, Institute of Biology, Freie Universität Berlin, Königin-Luise-Straße 1-3, 14195 Berlin, Germany.
| | - Frank Schreiber
- Division of Biodeterioration and Reference Organisms (4.1), Department of Materials and the Environment, Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany.
| |
Collapse
|
3
|
Epoxiconazole caused oxidative stress related DNA damage and apoptosis in PC12 rat Pheochromocytoma. Neurotoxicology 2022; 89:184-190. [DOI: 10.1016/j.neuro.2022.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 01/31/2022] [Accepted: 02/10/2022] [Indexed: 11/22/2022]
|
4
|
Pestana CB, Firman JW, Cronin MT. Incorporating lines of evidence from New Approach Methodologies (NAMs) to reduce uncertainties in a category based read-across: A case study for repeated dose toxicity. Regul Toxicol Pharmacol 2021; 120:104855. [DOI: 10.1016/j.yrtph.2020.104855] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/30/2020] [Accepted: 12/18/2020] [Indexed: 12/20/2022]
|
5
|
Hamdi H, Abid-Essefi S, Eyer J. Cytotoxic and genotoxic effects of epoxiconazole on F98 glioma cells. CHEMOSPHERE 2019; 229:314-323. [PMID: 31078888 DOI: 10.1016/j.chemosphere.2019.05.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 04/25/2019] [Accepted: 05/02/2019] [Indexed: 06/09/2023]
Abstract
Epoxiconazole (EPX) is a very effective fungicide of the triazole family. Given its wide spectrum of use, the increased application of this pesticide may represent a serious risk on human health. Previous studies have found that EPX is cytotoxic to cells, although the exact mechanism remains elusive. In particular, the effect on the nervous system is poorly elucidated. Here we evaluated the implication of oxidative stress in the neurotoxicity and studied its apoptotic mechanism of action. We demonstrated that the treatment by EPX reduces the viability of cells in a dose dependent manner with an IC50 of 50 μM. It also provokes the reduction of cell proliferation. EPX could trigger arrest in G1/S phase of cell cycle with low doses, however with IC50, it induced an accumulation of F98 cells in G2/M phase. Moreover, EPX induced cytoskeleton disruption as evidenced by immunocytochemical analysis. It provoked also DNA fragmentation in a concentration dependent manner. The EPX induced apoptosis, which was observed by morphological changes and by positive Annexin V FITC-PI staining concurrent with a depolarization of mitochondria. Furthermore, the cell mortality provoked by EPX was significantly reduced by pretreatment with Z-VAD-FMK, a caspase inhibitor. Moreover, N-acetylcysteine (NAC) strongly restores cell viability that has been inhibited by EPX. The results of these findings highlight the implication of ROS generation in the neurotoxicity induced by EPX, indicating that the production of ROS is the main cause of the induction of apoptosis probably via the mitochondrial pathway.
Collapse
Affiliation(s)
- Hiba Hamdi
- Laboratory for Research on Biologically Compatible Compounds, Faculty of Dental Medicine, University of Monastir, Avicenne Street, Monastir, 5019, Tunisia; Higher Institute of Biotechnology, University of Monastir, Tunisia
| | - Salwa Abid-Essefi
- Laboratory for Research on Biologically Compatible Compounds, Faculty of Dental Medicine, University of Monastir, Avicenne Street, Monastir, 5019, Tunisia
| | - Joel Eyer
- Laboratoire Micro et Nanomédecines Translationnelles (MINT), Inserm 1066, CNRS 6021, Institut de Biologie de la Santé, Centre Hospitalier Universitaire, Angers, 49033, France.
| |
Collapse
|
6
|
Analysis of Sister Chromatid Exchanges and Proliferation of Human Peripheral Blood Lymphocytes Exposed to Epoxiconazole. FOLIA VETERINARIA 2018. [DOI: 10.2478/fv-2018-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abstract
The potential genotoxic/cytotoxic effect of epoxiconazole was evaluated by means of sister chromatid exchanges (SCE) following the 24 and 48 h in vitro exposure of human peripheral blood lymphocytes to epoxiconazole at concentrations of: 5, 10, 25, 50 and 100 μg. ml–1. Dimethyl sulphoxide (DMSO), used as an epoxiconazole solvent, was used as a negative control and mitomycine (MMC) as a positive control. After the 24-hour exposure, we failed to observe a significant increase in SCE frequencies in comparison with the negative control, however, the concentrations of 10—100 μg.ml–1 caused a significant decrease in the proliferation index (PI; P < 0.001). Also, the 48-hour exposure produced no significant alterations in the SCE frequencies in comparison with the control. At epoxiconazole concentrations ranging from 10 to 50 μg.ml–1 we recorded a moderate to strong, dose-dependent inhibition of PI (P < 0.05; P < 0.01; P < 0.001), while at the highest dose (100 μg.ml–1) the reduction in PI compared to the control was less pronounced (P < 0.05). The reduction in PI at the concentration range of 10—100 μg.ml–1 depended on the number of cells in the M1, M2 and M3 phases of the cell cycle per total number of 100 evaluated metaphases. Our results indicated a significant cytotoxic or cytostatic effect on human peripheral blood lymphocytes.
Collapse
|
7
|
Šiviková K, Holečková B, Schwarzbacherová V, Galdíková M, Dianovský J. Potential chromosome damage, cell-cycle kinetics/and apoptosis induced by epoxiconazole in bovine peripheral lymphocytes in vitro. CHEMOSPHERE 2018; 193:82-88. [PMID: 29127838 DOI: 10.1016/j.chemosphere.2017.11.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 10/23/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
The epoxiconazole was tested in vitro for its potential on induction of chromosome damage and/or cell cycle kinetics in cultured bovine peripheral lymphocytes. Cytogenetic endpoints such as: Chromosome Aberrations (CA); Sister Chromatid Exchanges (SCE); Micronuclei (MN); Mitotic Index (MI); Proliferation Index (PI); and Cytokinesis Block Proliferation Index (CBPI) were investigated for 24 h and 48 h of incubation. The cultured lymphocytes were exposed to the epoxiconazole at concentrations of 2.5, 5, 10, 25, 50 and 100 μg mL-1. From our results is evident that treatment of bovine peripheral lymphocytes with the epoxiconazole was not related to DNA damage; no genotoxic effect and/or clastogenic/aneugenic effects were recorded. However, epoxiconazole has ability to significantly affect cell cycle kinetics/and induce apoptosis. A decrease of proliferation in the MI, CBPI and identically in the PI were observed; hence, cytostatic/cytotoxic effects of epoxiconazole have been recorded. The prolonged time of exposure at the highest concentration caused an inhibition of the replication. Electrophoretic analysis confirmed the epoxiconazole potential to induce ladder-like patterns of DNA fragments that are a hallmark of apoptosis.
Collapse
Affiliation(s)
- Katarína Šiviková
- Institute of Genetics, University of Veterinary Medicine and Pharmacy, Košice, Slovak Republic.
| | - Beáta Holečková
- Institute of Genetics, University of Veterinary Medicine and Pharmacy, Košice, Slovak Republic
| | - Viera Schwarzbacherová
- Institute of Genetics, University of Veterinary Medicine and Pharmacy, Košice, Slovak Republic
| | - Martina Galdíková
- Institute of Genetics, University of Veterinary Medicine and Pharmacy, Košice, Slovak Republic
| | - Ján Dianovský
- Institute of Genetics, University of Veterinary Medicine and Pharmacy, Košice, Slovak Republic
| |
Collapse
|
8
|
Drážovská M, Šiviková K, Holečková B, Dianovský J, Galdíková M, Schwarzbacherová V. Evaluation of potential genotoxic/cytotoxic effects induced by epoxiconazole and fenpropimorph-based fungicide in bovine lymphocytes in vitro. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2016; 51:769-776. [PMID: 27428828 DOI: 10.1080/03601234.2016.1198643] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Potential genotoxic/cytotoxic effects of the epoxiconazole/fenpropimorph-based fungicide were investigated using single cell gel electrophoresis and cytogenetic assays: chromosomal aberrations, sister chromatid exchanges, micronuclei and fluorescence in situ hybridization in cultured bovine lymphocytes. No statistically significant elevations of DNA damage and increases in cytogenetic endpoints were seen. However, evident cytotoxic effect presented as a decrease in mitotic and proliferation indices were recorded after exposure of bovine lymphocytes to the fungicide for 24 and 48 h at concentrations ranging from 3 to 15 µg mL(-1) (P < 0.05, P < 0.01, P < 0.001). Similarly, for 24 h an inhibition in the cytokinesis block proliferation index (CBPI) was obtained after exposure to the fungicide at concentrations ranging from 1.5 to 15 µg mL(-1) (P < 0.01, P < 0.001) in each donor.
Collapse
Affiliation(s)
- Monika Drážovská
- a Department of Biology and Genetics , University of Veterinary Medicine and Pharmacy in Košice , Košice , Slovak Republic
| | - Katarína Šiviková
- a Department of Biology and Genetics , University of Veterinary Medicine and Pharmacy in Košice , Košice , Slovak Republic
| | - Beáta Holečková
- a Department of Biology and Genetics , University of Veterinary Medicine and Pharmacy in Košice , Košice , Slovak Republic
| | - Ján Dianovský
- a Department of Biology and Genetics , University of Veterinary Medicine and Pharmacy in Košice , Košice , Slovak Republic
| | - Martina Galdíková
- a Department of Biology and Genetics , University of Veterinary Medicine and Pharmacy in Košice , Košice , Slovak Republic
| | - Viera Schwarzbacherová
- a Department of Biology and Genetics , University of Veterinary Medicine and Pharmacy in Košice , Košice , Slovak Republic
| |
Collapse
|
9
|
Chaâbane M, Tir M, Hamdi S, Boudawara O, Jamoussi K, Boudawara T, Ghorbel RE, Zeghal N, Soudani N. Improvement of Heart Redox States Contributes to the Beneficial Effects of Selenium Against Penconazole-Induced Cardiotoxicity in Adult Rats. Biol Trace Elem Res 2016; 169:261-70. [PMID: 26150403 DOI: 10.1007/s12011-015-0426-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 06/26/2015] [Indexed: 02/07/2023]
Abstract
The present study was performed to evaluate the protective effect of selenium (Se) against penconazole (PEN)-induced oxidative stress in the cardiac tissue of adult rats. Male Wistar rats were divided into four groups of six each. The first group represented the controls. For the second group (PEN), no treatment was performed during the first 6 days, and then, the rats received intraperitoneally 67 mg/kg body weight (bw) of PEN every 2 days from day 7 until day 15, the sacrifice day. For the third group (Se + PEN), Se was administered daily through the diet at a dose of 0.5 mg/kg of diet for 15 days. Rats of this group received also every 2 days PEN (67 mg/kg bw) from day 7 until day 15. The fourth group (Se) received daily, through the diet, Se (0.5 mg/Kg of diet) during 15 days. Our results showed that Se reduced significantly the elevated cardiac levels of malondialdehyde and protein carbonyl following PEN treatment, and attenuated DNA fragmentation induced by this fungicide. In addition, Se modulated the alterations of antioxidant status: enzymatic (superoxide dismutase, glutathione peroxidase, and catalase) and nonenzymatic (glutathione and vitamin C) antioxidants in the heart of PEN-treated rats. This trace element was also able to alleviate perturbations of lipid profile. The protective effect of selenium was further evident through the histopathological changes produced by PEN in the heart tissue. Taken together, our results indicated that Se might be beneficial against PEN-induced cardiac oxidative damage in rats.
Collapse
Affiliation(s)
- Mariem Chaâbane
- Enzymes and Bioconversion Unit, National Engineering School of Sfax, University of Sfax, 3038, Sfax, Tunisia
- Animal Physiology Laboratory, Department of Life Sciences, Sfax Faculty of Sciences, University of Sfax, BP 1171, 3000, Sfax, Tunisia
| | - Meriem Tir
- Physiology and aquatic environment laboratory, UR13 ES 35, Tunis Faculty of Sciences, 2092, University of Tunis El Manar, Farhat Hached University Campus El Manar, Tunis. B.P.n 94, 1068, Rommana, Tunisia
| | - Safa Hamdi
- Biochemistry Laboratory, University of Sfax, CHU Hedi Chaker, 3029, Sfax, Tunisia
| | - Ons Boudawara
- Histopathology Laboratory, University of Sfax, CHU Habib Bourguiba, 3029, Sfax, Tunisia
| | - Kamel Jamoussi
- Biochemistry Laboratory, University of Sfax, CHU Hedi Chaker, 3029, Sfax, Tunisia
| | - Tahia Boudawara
- Histopathology Laboratory, University of Sfax, CHU Habib Bourguiba, 3029, Sfax, Tunisia
| | - Raoudha Ellouze Ghorbel
- Enzymes and Bioconversion Unit, National Engineering School of Sfax, University of Sfax, 3038, Sfax, Tunisia
| | - Najiba Zeghal
- Animal Physiology Laboratory, Department of Life Sciences, Sfax Faculty of Sciences, University of Sfax, BP 1171, 3000, Sfax, Tunisia.
| | - Nejla Soudani
- Animal Physiology Laboratory, Department of Life Sciences, Sfax Faculty of Sciences, University of Sfax, BP 1171, 3000, Sfax, Tunisia
| |
Collapse
|
10
|
Urzúa J, González-Vargas C, Sepúlveda F, Ureta-Zañartu MS, Salazar R. Degradation of conazole fungicides in water by electrochemical oxidation. CHEMOSPHERE 2013; 93:2774-2781. [PMID: 24140400 DOI: 10.1016/j.chemosphere.2013.09.035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 09/04/2013] [Accepted: 09/06/2013] [Indexed: 06/02/2023]
Abstract
The electrochemical oxidation (EO) treatment in water of three conazole fungicides, myclobutanil, triadimefon and propiconazole, has been carried out at constant current using a BDD/SS system. First, solutions of each fungicide were electrolyzed to assess the effect of the experimental parameters such as current, pH and fungicide concentration on the decay of each compound and total organic carbon abatement. Then a careful analysis of the degradation by-products was made by high performance liquid chromatography, ion chromatography and gas chromatography coupled with mass spectrometry in order to provide a detailed discussion on the original reaction pathways. Thus, during the degradation of conazole fungicides by the electrochemical oxidation process, aromatic intermediates, aliphatic carboxylic acids and Cl(-) were detected prior to their complete mineralization to CO2 while NO3(-) anions remained in the treated solution. This is an essential preliminary step towards the applicability of the EO processes for the treatment of wastewater containing conazole fungicides.
Collapse
Affiliation(s)
- J Urzúa
- Departamento de Ciencias del Ambiente, Facultad de Química y Biología, Universidad de Santiago de Chile, USACH, Casilla 40, Correo 33, Santiago, Chile
| | | | | | | | | |
Collapse
|
11
|
Nesnow S. Integration of toxicological approaches with “omic” and related technologies to elucidate mechanisms of carcinogenic action: Propiconazole, an example. Cancer Lett 2013. [DOI: 10.1016/j.canlet.2012.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
12
|
Holečková B, Šiviková K, Dianovský J, Galdíková M. Effect of triazole pesticide formulation on bovine culture cells. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2013; 48:1080-1088. [PMID: 24007485 DOI: 10.1080/03601234.2013.824224] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
To date, most data about the possible genotoxic effect of triazole pesticides are focused on laboratory animals resulting in limited information on further non-target organisms such as cattle. The objective of the present study was to investigate the effect of triazole (tebuconazole/prothioconazole) fungicide formulation on the induction of chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and DNA fragmentation in bovine cultured lymphocytes. Our results showed that the fungicide formulation did not induce significant number of CAs in bovine cells after 24 h treatment. Nevertheless, the dose-dependent reduction of mitotic division was observed, with the strongest effect at 30.0 μg mL(-1) in both donors (P < 0.01 and P < 0.001, respectively). Prolonged 48 h exposure caused the increased level of breaks in treated cultures (3.0-15.0 μg mL(-1); P < 0.05) and significant decrease in mitotic index (MI). The tested fungicide failed to produce any statistical changes in the SCE frequency neither after 24 h nor 48 h treatment. However, the significant decline of the proliferation index (PI) was observed after 24 h indicating the fungicide influence on cell cycle kinetics. Prolonged 48 h exposure caused cytotoxicity reflecting in lower PI value relative to control mainly at the highest fungicide concentrations (30.0 μg mL(-1), P < 0.001). Using painting probes for bovine chromosomes 1, 5 and 7 (BTA1, BTA5 and BTA7) only low levels of aneuploidies were detected. Significant increase of polyploidy cells (P < 0.05) was induced by a 3.0 μg mL(-1) dose of the fungicide after 48 h. DNA fragmentation assay didn't reveal the presence of DNA nucleosome ladder in cell cultures at any time (24 h and 48 h) and fungicide concentration.
Collapse
Affiliation(s)
- Beáta Holečková
- Department of Biology and Genetics, University of Veterinary Medicine and Pharmacy, Košice, Slovak Republic.
| | | | | | | |
Collapse
|
13
|
Ross JA, Leavitt SA, Schmid JE, Nelson GB. Quantitative changes in endogenous DNA adducts correlate with conazole in vivo mutagenicity and tumorigenicity. Mutagenesis 2012; 27:541-9. [PMID: 22492202 DOI: 10.1093/mutage/ges017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The mouse liver tumorigenic conazole fungicides triadimefon and propiconazole have previously been shown to be in vivo mouse liver mutagens in the Big Blue™ transgenic mutation assay when administered in feed at tumorigenic doses, whereas the nontumorigenic conazole myclobutanil was not mutagenic. DNA sequencing of the mutants recovered from each treatment group as well as from animals receiving control diet revealed that propiconazole- and triadimefon-induced mutations do not represent general clonal expansion of background mutations, and support the hypothesis that they arise from the accumulation of endogenous reactive metabolic intermediates within the liver in vivo. We therefore measured the spectra of endogenous DNA adducts in the livers of mice from these studies to determine if there were quantitative or qualitative differences between mice receiving tumorigenic or nontumorigenic conazoles compared to concurrent control animals. We resolved and quantitated 16 individual adduct spots by (32)P postlabelling and thin layer chromatography using three solvent systems. Qualitatively, we observed the same DNA adducts in control mice as in mice receiving conazoles. However, the 13 adducts with the highest chromatographic mobility were, as a group, present at significantly higher amounts in the livers of mice treated with propiconazole and triadimefon than in their concurrent controls, whereas this same group of DNA adducts in the myclobutanil-treated mice was not different from controls. This same group of endogenous adducts were significantly correlated with mutant frequency across all treatment groups (P = 0.002), as were total endogenous DNA adduct levels (P = 0.005). We hypothesise that this treatment-related increase in endogenous DNA adducts, together with concomitant increases in cell proliferation previously reported to be induced by conazoles, explain the observed increased in vivo mutation frequencies previously reported to be induced by treatment with propiconazole and triadimefon.
Collapse
Affiliation(s)
- Jeffrey A Ross
- National Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
| | | | | | | |
Collapse
|
14
|
Hester S, Moore T, Padgett WT, Murphy L, Wood CE, Nesnow S. The Hepatocarcinogenic Conazoles: Cyproconazole, Epoxiconazole, and Propiconazole Induce a Common Set of Toxicological and Transcriptional Responses. Toxicol Sci 2012; 127:54-65. [DOI: 10.1093/toxsci/kfs086] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
15
|
Murphy LA, Moore T, Nesnow S. Propiconazole-enhanced hepatic cell proliferation is associated with dysregulation of the cholesterol biosynthesis pathway leading to activation of Erk1/2 through Ras farnesylation. Toxicol Appl Pharmacol 2012; 260:146-54. [PMID: 22361350 DOI: 10.1016/j.taap.2012.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 01/21/2012] [Accepted: 02/08/2012] [Indexed: 12/20/2022]
Abstract
Propiconazole is a mouse hepatotumorigenic fungicide designed to inhibit CYP51, a key enzyme in the biosynthesis of ergosterol in fungi and is widely used in agriculture to prevent fungal growth. Metabolomic studies in mice revealed that propiconazole increased levels of hepatic cholesterol metabolites and bile acids, and transcriptomic studies revealed that genes within the cholesterol biosynthesis, cholesterol metabolism and bile acid biosyntheses pathways were up-regulated. Hepatic cell proliferation was also increased by propiconazole. AML12 immortalized hepatocytes were used to study propiconazole's effects on cell proliferation focusing on the dysregulation of cholesterol biosynthesis and resulting effects on Ras farnesylation and Erk1/2 activation as a primary pathway. Mevalonate, a key intermediate in the cholesterol biosynthesis pathway, increases cell proliferation in several cancer cell lines and tumors in vivo and serves as the precursor for isoprenoids (e.g. farnesyl pyrophosphate) which are crucial in the farnesylation of the Ras protein by farnesyl transferase. Farnesylation targets Ras to the cell membrane where it is involved in signal transduction, including the mitogen-activated protein kinase (MAPK) pathway. In our studies, mevalonic acid lactone (MVAL), a source of mevalonic acid, increased cell proliferation in AML12 cells which was reduced by farnesyl transferase inhibitors (L-744,832 or manumycin) or simvastatin, an HMG-CoA reductase inhibitor, indicating that this cell system responded to alterations in the cholesterol biosynthesis pathway. Cell proliferation in AML12 cells was increased by propiconazole which was reversed by co-incubation with L-744,832 or simvastatin. Increasing concentrations of exogenous cholesterol muted the proliferative effects of propiconazole and the inhibitory effects of L-733,832, results ascribed to reduced stimulation of the endogenous cholesterol biosynthesis pathway. Western blot analysis of subcellular fractions from control, MVAL or propiconazole-treated cells revealed increased Ras protein in the cytoplasmic fraction of L-744,832-treated cells, while propiconazole or MVAL reversed these effects. Western blot analysis indicated that phosphorylation of Erk1/2, a protein downstream of Ras, was increased by propiconazole. These data indicate that propiconazole increases cell proliferation by increasing the levels of cholesterol biosynthesis intermediates presumably through a negative feedback mechanism within the pathway, a result of CYP51 inhibition. This feedback mechanism increases Erk1/2 signaling through mevalonate-mediated Ras activation. These results provide an explanation for the observed effects of propiconazole on hepatic cholesterol pathways and on the increased hepatic cell proliferation induced by propiconazole in mice.
Collapse
Affiliation(s)
- Lynea A Murphy
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | | | | |
Collapse
|
16
|
Shane BS, Zeiger E, Piegorsch WW, Booth ED, Goodman JI, Peffer RC. Re-evaluation of the Big Blue® mouse assay of propiconazole suggests lack of mutagenicity. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2012; 53:1-9. [PMID: 22329022 DOI: 10.1002/em.20689] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Propiconazole (PPZ) is a conazole fungicide that is not mutagenic, clastogenic, or DNA damaging in standard in vitro and in vivo genetic toxicity tests for gene mutations, chromosome aberrations, DNA damage, and cell transformation. However, it was demonstrated to be a male mouse liver carcinogen when administered in food for 24 months only at a concentration of 2,500 ppm that exceeded the maximum tolerated dose based on increased mortality, decreased body weight gain, and the presence of liver necrosis. PPZ was subsequently tested for mutagenicity in the Big Blue® transgenic mouse assay at the 2,500 ppm dose, and the result was reported as positive by Ross et al. ([2009]: Mutagenesis 24:149-152). Subsets of the mutants from the control and PPZ-exposed groups were sequenced to determine the mutation spectra and a multivariate clustering analysis method purportedly substantiated the increase in mutant frequency with PPZ (Ross and Leavitt. [2010]: Mutagenesis 25:231-234). However, as reported here, the results of the analysis of the mutation spectra using a conventional method indicated no treatment-related differences in the spectra. In this article, we re-examine the Big Blue® mouse findings with PPZ and conclude that the compound does not act as a mutagen in vivo.
Collapse
|
17
|
Nesnow S, Grindstaff RD, Lambert G, Padgett WT, Bruno M, Ge Y, Chen PJ, Wood CE, Murphy L. Propiconazole increases reactive oxygen species levels in mouse hepatic cells in culture and in mouse liver by a cytochrome P450 enzyme mediated process. Chem Biol Interact 2011; 194:79-89. [DOI: 10.1016/j.cbi.2011.08.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 08/04/2011] [Accepted: 08/05/2011] [Indexed: 01/14/2023]
|
18
|
Ross JA, Blackman CF, Thai SF, Li Z, Kohan M, Jones CP, Chen T. A potential microRNA signature for tumorigenic conazoles in mouse liver. Mol Carcinog 2010; 49:320-3. [PMID: 20175128 DOI: 10.1002/mc.20620] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Triadimefon, propiconazole, and myclobutanil are conazoles, an important class of agricultural fungicides. Triadimefon and propiconazole are mouse liver tumorigens, while myclobutanil is not. As part of a coordinated study to understand the molecular determinants of conazole tumorigenicity, we analyzed the microRNA expression levels in control and conazole-treated mice after 90 d of administration in feed. MicroRNAs (miRNAs) are small noncoding RNAs composed of approximately 19-24 nucleotides in length, and have been shown to interact with mRNA (usually 3' UTR) to suppress its expression. MicroRNAs play a key role in diverse biological processes, including development, cell proliferation, differentiation, and apoptosis. Groups of mice were fed either control diet or diet containing 1800 ppm triadimefon, 2500 ppm propiconazole, or 2000 ppm myclobutanil. MicroRNA was isolated from livers and analyzed using Superarray whole mouse genome miRNA PCR arrays from SABioscience. Data were analyzed using the significance analysis of microarrays (SAM) procedure. We identified those miRNAs whose expression was either increased or decreased relative to untreated controls with q < or = 0.01. The tumorigenic conazoles induced many more changes in miRNA expression than the nontumorigenic conazole. A group of 19 miRNAs was identified whose expression was significantly altered in both triadimefon- and propiconazole-treated animals but not in myclobutanil-treated animals. All but one of the altered miRNAs were downregulated compared to controls. This pattern of altered miRNA expression may represent a signature for tumorigenic conazole exposure in mouse liver after 90 d of treatment.
Collapse
Affiliation(s)
- Jeffrey A Ross
- Integrated Systems Toxicology Division, NHEERL, U.S. EPA, Research Triangle Park, North Carolina, USA
| | | | | | | | | | | | | |
Collapse
|
19
|
Ortiz PA, Bruno ME, Moore T, Nesnow S, Winnik W, Ge Y. Proteomic Analysis of Propiconazole Responses in Mouse Liver: Comparison of Genomic and Proteomic Profiles. J Proteome Res 2010; 9:1268-78. [DOI: 10.1021/pr900755q] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Pedro A. Ortiz
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
| | - Maribel E. Bruno
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
| | - Tanya Moore
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
| | - Stephen Nesnow
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
| | - Witold Winnik
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
| | - Yue Ge
- National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711
| |
Collapse
|
20
|
Abstract
The mouse liver tumorigenic conazole fungicides triadimefon and propiconazole have previously been shown to be in vivo mouse liver mutagens in the Big Blue transgenic mutation assay when administered in feed at tumorigenic doses, whereas the non-tumorigenic conazole myclobutanil was not mutagenic. DNA sequencing of the mutants recovered from each treatment group as well as from animals receiving control diet was conducted to gain additional insight into the mode of action by which tumorigenic conazoles induce mutations. Relative dinucleotide mutabilities (RDMs) were calculated for each possible dinucleotide in each treatment group and then examined by multivariate statistical analysis techniques. Unsupervised hierarchical clustering analysis of RDM values segregated two independent control groups together, along with the non-tumorigen myclobutanil. The two tumorigenic conazoles clustered together in a distinct grouping. Partitioning around mediods of RDM values into two clusters also groups the triadimefon and propiconazole together in one cluster and the two control groups and myclobutanil together in a second cluster. Principal component analysis of these results identifies two components that account for 88.3% of the variability in the points. Taken together, these results are consistent with the hypothesis that propiconazole- and triadimefon-induced mutations do not represent clonal expansion of background mutations and support the hypothesis that they arise from the accumulation of reactive electrophilic metabolic intermediates within the liver in vivo.
Collapse
Affiliation(s)
- Jeffrey A Ross
- Carcinogenesis Branch, Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC 27711, USA.
| | | |
Collapse
|
21
|
Scientific Opinion on Risk Assessment for a Selected Group of Pesticides from the Triazole Group to Test Possible Methodologies to Assess Cumulative Effects from Exposure through Food from these Pesticides on Human Health. EFSA J 2009. [DOI: 10.2903/j.efsa.2009.1167] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
22
|
Nesnow S, Ward W, Moore T, Ren H, Hester SD. Discrimination of Tumorigenic Triazole Conazoles from Phenobarbital by Transcriptional Analyses of Mouse Liver Gene Expression. Toxicol Sci 2009; 110:68-83. [DOI: 10.1093/toxsci/kfp076] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
|