Ayşe Yavuz Kocaman

The in vitro genotoxic effects of a commercial formulation of α‐cypermethrin in human peripheral blood lymphocytes

α‐Cypermethrin, a highly active pyrethroid insecticide, is effective against a wide range of insects encountered in agriculture and animal husbandry. The potential genotoxicity of a commercial formulation of α‐cypermethrin (Fastac 100 EC, containing 10% α‐cypermethrin as the active ingredient) on human peripheral lymphocytes was examined in vitro by sister chromatid exchange (SCE), chromosomal aberrations (CAs), and micronucleus (MN) tests. The human lymphocytes were treated with 5, 10, 15, and 20 μg/ml of α‐cypermethrin for 24‐ and 48‐hr. α‐Cypermethrin induced SCEs and CAs significantly at all concentrations and treatment times and MN formation was significantly induced at 5 and 10 μg/ml of α‐cypermethrin when compared with both the control and solvent control. Binuclear cells could not be detected sufficiently in the highest two concentration of α‐cypermethrin (15 and 20 μg/ml) for both the 24‐ and 48‐hr treatment times. α‐Cypermethrin decreased the proliferation index (PI) at three high concentrations (10, 15, and 20 μg/ml) for both treatment periods as compared with the control groups. In addition, α‐cypermethrin reduced both the mitotic index (MI) and nuclear division index (NDI) significantly at all concentrations for two treatment periods. The PI and MI were reduced by α‐cypermethrin in a concentration‐dependent manner during both treatment times. In general, α‐cypermethrin showed higher cytotoxic and cytostatic effects than positive control (MMC) at the two highest concentrations for the 24‐ and 48‐hr treatment periods. The present study is the first to report the genotoxic and cytotoxic effects of commercial formulation of α‐cypermethrin in peripheral blood lymphocytes. Environ. Mol. Mutagen., 2009.

In vitro investigation of the genotoxic and cytotoxic effects of thiacloprid in cultured human peripheral blood lymphocytes

Thiacloprid, a neonicotinoid insecticide, is widely used for controlling various species of pests on many crops. The potential genotoxic effects of thiacloprid on human peripheral blood lymphocytes (PBLs) were investigated in vitro by the chromosome aberrations (CAs), sister chromatid exchanges (SCEs), and cytokinesis‐block micronucleus (MN) assays. The human PBLs were treated with 75, 150, and 300 μg/mL thiacloprid in the absence and presence of an exogenous metabolic activator (S9 mix). Thiacloprid increased the CAs and SCEs significantly at all concentrations (75, 150, and 300 μg/mL) both in the absence and presence of the S9 mix and induced a significant increase in MN and nucleoplasmic bridge formations at all concentrations for 24 h and at 75 and 150 μg/mL for 48‐h treatment periods in the absence of the S9 mix; and at all concentrations in the presence of the S9 mix when compared with the control and solvent control. Thiacloprid was also found to significantly induce nuclear bud (NBUD) formation at 300 μg/mL for 24 h and at 150 μg/mL for 48‐h treatment times in the absence of the S9 mix and at the two highest concentrations (150 and 300 μg/mL) in the presence of the S9 mix. Thiacloprid significantly decreased the mitotic index, proliferation index, and nuclear division index for all concentrations both in the absence and presence of the S9 mix.

Genotoxic and cytotoxic effects of flumetralin in human peripheral blood lymphocytes in vitro.

Flumetralin, a synthetic plant growth regulator with herbicidal activity belonging to the 2,6-dinitroaniline class of chemicals, has been evaluated for its ability to induce genotoxicity in human peripheral blood lymphocytes (PBLs). The potential genotoxic and cytotoxic effects of flumetralin were investigated in vitro by chromosome aberration (CA) and cytokinesis-block micronucleus assays. Human PBLs were treated with 125, 250, 500, and 1000 µg/mL flumetralin for 24 and 48 h. Flumetralin statistically significantly increased the frequency of structural CAs at the three highest concentrations (250, 500, and 1000 µg/mL) for both treatment periods (24 and 48 h) when compared with both the negative and solvent controls. In addition, micronucleus formation was significantly induced at higher concentrations (250, 500, and 1000 µg/mL) for 24 h and at 125 and 500 µg/mL of flumetralin for the 48-h treatment period compared with the controls. Because of the excessive cytostatic effects of flumetralin, binuclear cells could not be detected sufficiently at the highest two concentrations (500 and 1000 µg/mL) for the 48-h treatment period. Furthermore, flumetralin significantly decreased the mitotic index and nuclear division index for all concentrations and treatment times compared with the control groups. The present results indicate that flumetralin was clastogenic and cytotoxic/cytostatic to human PBLs. This study presents the first report of the genotoxic and cytotoxic properties of flumetralin.

The genotoxic and antigenotoxic effects of tannic acid in human lymphocytes.

The genotoxicity of tannic acid (TA, tannin) were investigated using chromosome aberration (CA), sister chromatid exchange (SCE), and micronucleus (MN) test systems in human peripheral lymphocytes. Also, the antigenotoxicity of TA against known mutagen EMS was also examined. The lymphocytes were treated with 1.74 × 10−5, 3.49 × 10−5, and 6.98 × 10−5 µM of TA for 24- and 48-hour treatment periods. For the antigenotoxicity of TA, the lymphocytes were treated with three different concentrations of TA and 2.71 µM of EMS. TA synergically induced the CA alone and with the mixture of EMS. However, TA did not induce the SCE alone, whereas TA and EMS as a mixture also synergically induced SCE. TA alone showed no clear effect on micronucleus formation, and it did not induce the MN when used with EMS as a mixture. In addition, TA showed a synergistic cytotoxic effect by decreasing the mitotic and nuclear division indices. The replication index was decreased at all concentrations for 48 hours of treatment time by TA and EMS as a mixture.

In vitro evaluation of the protective effects of 4-thujanol against mitomycin-C and cyclophosphamide-induced genotoxic damage in human peripheral lymphocytes

4-Thujanol (sabinene hydrate), a bicyclic monoterpene alcohol, is found in the essential oils of many aromatic and medicinal plants and is widely used as a fragrance and flavouring agent in many different products. The aim of this study was to evaluate the protective effects of 4-thujanol against the genotoxic effects induced by mitomycin C (MMC) and cyclophosphamide (CP) in human lymphocytes, using the chromosome aberrations, sister chromatid exchanges, and micronucleus tests, in the absence and in the presence of S9 mix, respectively. The cells were treated with 0.25 µg/mL MMC and 28 µg/mL CP as alone and cotreated with 13 + 0.25, 26 + 0.25, and 52 + 0.25 µg/mL 4-thujanol + MMC and with 13 + 28, 26 + 28, and 52 + 28 µg/mL 4-thujanol + CP as a mixture. The present study showed that 4-thujanol was unable to reduce the genetic damage induced by MMC, in the absence of S9 mix. On the other hand, probably the metabolites of 4-thujanol act as an antagonist and markedly antagonize CP-induced genotoxicity, in the presence of S9 mix. In general, 4-thujanol + MMC and 4-thujanol + CP decreased the mitotic index, proliferation index and nuclear division index to the same extent or more than those of individual exposure of MMC or CP. In conclusion, 4-thujanol significantly reduced (p < 0.001) the genotoxic damage induced by CP but not MMC when compared with the respective positive control alone. We can suggest that 4-thujanol may improve the chemopreventive effects and may also reduce the harmful side effects of CP, which is widely used in chemotherapy against cancer, without reducing its antiproliferative activities.

Evaluation of the genotoxicity of commercial formulations of ethephon and ethephon+cyclanilide on Allium cepa L. root meristematic cells

Abstract Cytogenotoxic effects of a commercial formulation of ethephon (ETF) and a commercially formulated mixture of ethephon+cyclanilide (ETF+CYC), which are used as plant growth regulators (PGRs) in modern agriculture, were investigated by using the anaphase-telophase chromosome aberration (CA) assay in root meristem cells of Allium cepa L. A. cepa roots were treated with 25 (EC50/2), 50 (EC50), and 100 ppm (EC50×2) of ETF, and with the same concentrations of ETF+CYC, for 24, 48, and 72 h periods. Both compounds increased various types of aberrations in the organization and morphology of the chromosomes in test material. These aberrations were clastogenic (bridges and fragments), aneugenic (disturbed anaphase-telophase, C-mitosis, binucleated cells, vagrant chromosomes, and polyploidy), and sticky (stickiness). Commercial formulations of ETF and ETF+CYC significantly increased the percentage of total aberrations, and the percentage of abnormal cells at all concentrations (25, 50, and 100 ppm), and treatment times (24, 48, and 72 h) when compared with the negative control. However, the commercially formulated mixture of ETF+CYC increased the CA formation more than commercial formulation of ETF alone (except the 50 ppm concentration, for 72 h). In addition, ETF and ETF+CYC significantly decreased the mitotic index (MI) at all concentrations and treatment times compared to both the negative and respective positive control, methyl methanesulfonate. The results of this study indicate that in the tested experimental conditions, the commercial formulations of ETF and ETF+CYC are genotoxic and induce cytotoxic effects in the root meristem cells of A. cepa.

Cytogenotoxic effects of venlafaxine hydrochloride on cultured human peripheral blood lymphocytes

Abstract The potential genotoxic effect of venlafaxine hydrochloride (venlafaxine), an antidepressant drug-active ingredient, was investigated by using in vitro chromosome aberrations (CAs) and cytokinesis-block micronucleus (CBMN) assays in human peripheral blood lymphocytes (PBLs). Mitotic index (MI) and cytokinesis-block proliferation index (CBPI) were also calculated to determine the cytotoxicity of this active drug. For this aim, the human PBLs were treated with 25, 50, and 100 µg/ml venlafaxine for 24 h and 48 h. The results of this study showed that venlafaxine significantly induced the formation of structural CA and MN for all concentrations (25, 50, and 100 µg/ml) and treatment periods (24 h and 48 h) when compared with the negative and the solvent control (except 25 µg/ml at 48 h for MN). In addition, the increases in the percentage of structural CA and MN were concentration-dependent for both treatment times. With regard to cell cycle kinetics, venlafaxine significantly decreased the MI at all concentrations, and also CBPI at the higher concentrations for both treatment times as compared to the control groups. The present results indicate for the first time that venlafaxine had significant clastogenic and cytotoxic effects at the tested concentrations (25, 50, and 100 µg/ml) in the human PBLs, in vitro; therefore, its excessive and careless use may pose a potential risk to human health.

The genotoxic and antigenotoxic potential of the methanolic root extract of Glycyrrhiza glabra L. on human peripheral blood lymphocytes

Abstract Glycyrrhiza glabra L. (licorice) is one of the most important medicinal plants, which is widely used throughout the world both in traditional and contemporary medical industries. This study was undertaken to investigate the potential genotoxic activity of G. glabra methanolic root extract, and its possible antigenotoxic properties against mitomycin C (MMC)-induced DNA damage in in vitro chromosome aberrations (CAs) and cytokinesis-block micronucleus (CBMN) assays in human peripheral blood lymphocytes (PBLs). Lymphocytes were treated with 25, 50, and 100 µg/ml G. glabra methanolic root extract alone as well as in combination with MMC (0.1 µg/ml) for 24 and 48 h treatment periods. It was found that there were no statistically significant differences between the negative control and the groups treated with all concentrations of G. glabra root extract of alone (p > 0.05), demonstrating the absence of genotoxic effects at both 24 and 48 h treatment periods. Besides, the co-treatment of G. glabra methanolic root extract and MMC significantly decreased the percentage of structural CAs and MN formation when compared with the culture treated with MMC alone (p < 0.001). In addition, the negative interaction factor (IF) values obtained for all combinations represent an antagonistic effect of G. glabra versus MMC. We can state that this extract acts as an antagonist and markedly decreased MMC-induced cytogenotoxicity. In conclusion, the present results demonstrate that in the tested experimental conditions, G. glabra methanolic root extract is not genotoxic in cultured human PBLs and has also antigenotoxic activity against MMC, which is widely used in chemotherapy against cancer.