Deniz Yüzbaşıoğlu

The evaluation of the genotoxicity of two food preservatives: Sodium benzoate and potassium benzoate

In this study, the genotoxic effects of sodium benzoate (SB) and potassium benzoate (PB) were investigated in cultured human peripheral lymphocytes using chromosomal aberrations (CA), sister chromatid exchange (SCE), and micronuclei (MN). The level of nuclear DNA damage of SB and PB were also evaluated using the comet assay. The lymphocytes were incubated with different concentrations of SB (6.25, 12.5, 25, 50, and 100 μg/ml) and PB (62.5, 125, 250, 500, and 1000 μg/ml). A significant increase was observed in CA, SCE, and MN, in almost all treatments compared to negative controls. SB and PB significantly decreased the mitotic index (MI) in all the treatments, compared to the negative controls. However, neither of the additives affected the replication index (RI). Although SB significantly increased DNA damage, PB did not cause a significant increase in DNA damage. The present results indicate that SB and PB are clastogenic, mutagenic and cytotoxic to human lymphocytes in vitro.

Does potassium sorbate induce genotoxic or mutagenic effects in lymphocytes

The present study evaluates the genotoxic potential of potassium sorbate (PS) in cultured and isolated human lymphocytes. To assess the damage caused by PS in humans, we designed in vitro experiments by measuring chromosomal aberrations (CAs), sister-chromatid exchanges (SCEs), micronucleus (MN) and comet assays. Lymphocytes were treated with negative control (sterile distilled water), positive control (MMC for cultured lymphocytes, and H(2)O(2) for isolated lymphocytes) and four concentrations (125, 250, 500, and 1000 microg/ml) of PS. According to the results, PS treatment significantly increases the CAs (with or without gaps at 500 and 1000 microg/ml concentrations) and SCEs (at 250, 500, 1000 microg/ml for 24h and 125, 250, 500, 1000 microg/ml for 48h) compared with vehicle control. Following treatment of the isolated lymphocytes for 1h, significant PS-induced DNA strand breaks were observed, at all concentrations. However, PS failed to significantly affect the MN assay. On the contrary, PS does not cause cell cycle delay as noted by the non-significant decrease in the cytokinesis-block proliferation index (CBPI) and replicative index (RI). Only a slight decrease was observed in the mitotic index (MI) at the highest concentration for both treatment times. From the results, PS is clearly seen to be genotoxic to the human peripheral blood lymphocytes in vitro.

Cytological effects of the herbicide racer “flurochloridone” on Allium cepa

Abstract The present investigation was carried out to study the cytological effects of the herbicide racer “flurochloridone” (3-chloro-4-(chloromethyl)-1-[3-(trifluoromethyl)= phenyl]-2-pyrrolidinone) on Allium cepa with respect to the cell response, mitotic index, mitotic abnormalities and chromosome aberrations. The roots of bulbs were treated with the following concentrations depending on the root growth inhibition test: 80 ppm (LD50), 40 ppm (LD50/2) and 20 ppm (LD50/4). The results indicated that flurochloridone herbicide reduced the mitotic division in A. cepa as compared to their control groups. The reduction in mitotic activity was more significant when the concentration of the herbicide increased and the exposure time was prolonged. The treatment conducted with flurochloridone induced a significant percentage of abnormal mitosis. Seven types of abnormalities were recorded: C-metaphase, laggards, stickiness, bridges, fragments, multipolarity and poliploidy. Micronucleated cells were also observed at interphase. In additon, in pretreated root tips, chromosome breaks, fragments and sister union were detected.

Genotoxic action of fungicide Conan 5FL (Hexaconazole) on mammalian cells in vivo and in vitro

The genotoxic effects of fungicide Conan 5FL (containing 50 g/L hexaconazole) in mouse bone-marrow cells and human lymphocytes have been evaluated. Three different concentrations of Conan 5FL (17.50, 35.0, and 70.0 μg/mL for human lymphocytes and 17.50, 35.0, and 70.0 mg/kg for mouse bone marrow cells) were studied. Conan 5FL induced significant increases (except 17.5 mg/kg for mouse bone marrow) in the frequency of chromosomal aberrations (CAs) in both test systems. This fungicide caused structural and numerical abnormalities in both mammalian cells. These are sister chromatid union, chromatid and chromosome breaks, fragments, dicentric and ring chromosomes, and polyploidy. Significant increase was found in induction and in minimum-maximum numbers of sister chromatid exchanges (SCEs) at all treatments compared with the negative control. Conan 5FL did not affect the replication index (RI) in human lymphocyte cultures, however, it significantly decreased the mitotic index (MI) in all treatment concentrations in both test systems. Using of Conan 5FL should be reconsidered due to its possible cytotoxic, clastogenic and mutagenic effects.

DNA damage in human lymphocytes exposed to four food additives in vitro.

In vitro genotoxic effects of antioxidant additives, such as citric acid (CA) and phosphoric acid (PA) and their combination, as well as antimicrobial additives, such as benzoic acid (BA) and calcium propionate (CP), on human lymphocytes were determined using alkaline single-cell gel electrophoresis. There was a significant increase in the DNA damage in human lymphocytes after 1 h of in vitro exposure to CA, PA, BA and CP (200, 25–200, 50–500, 50–1000 μg/mL, respectively). The combination of CA and PA significantly increased the mean tail intensity at all the concentrations used (25–200 μg/mL) and significantly increased the mean tail length mainly after higher concentrations (100 and 200 μg/mL). Data in this study showed that the concentrations of food additives used induce DNA damage and PA was the most genotoxic and CA was less genotoxic additives among them.

Assessment of the genotoxic effects of organophosphorus insecticides phorate and trichlorfon in human lymphocytes

In vitro genotoxic effects of organophosphorus insecticides Phorate (PHR) and Trichlorfon (TCF) were investigated using four genotoxicity endpoints. Different concentration ranges between 0.25–2.00 μg mL−1 of PHR and 2.34–37.50 μg mL−1 of TCF were applied to lymphocytes. PHR and TCF significantly increased the frequency of chromosomal aberrations (except 2.34 μg mL−1 for TCF) and sister chromatid exchanges at all treatment times and concentrations. Most of the used concentrations induced a significant increase in the frequency of micronuclei. Furthermore, PHR and TCF significantly decreased the mitotic index at the higher concentrations after 24‐ and 48‐h treatments. In the comet assay, PHR and TCF significantly increased the comet tail at all concentrations. However, the comet tail intensity was significantly increased at only the highest concentration of PHR and at all concentrations of TCF. According to these results, PHR and TCF possess clastogenic, mutagenic, and DNA damaging effects in human lymphocytes in vitro.

Genotoxicity of monosodium glutamate

Monosodium glutamate (MSG) is one of the most widely used flavor enhancers throughout the world. The aim of this study is to investigate the genotoxic potential of MSG by using chromosome aberrations (CAs), sister-chromatid exchanges (SCEs), cytokinesis-blocked micronucleus (CBMN), and random amplified polymorphic DNA-polimerase chain reaction (RAPD-PCR) in cultured human lymphocytes and alkaline comet assays in isolated human lymphocytes, which were incubated with six concentrations (250, 500, 1000, 2000, 4000 and 8000 μg/mL) of MSG. The result of this study indicated that MSG significantly and dose dependently increased the frequencies of CAs, SCE and MN in all treatments and times, compared with control. However, the replication (RI) and nuclear division indices (NDI) were not affected. In this paper, in vitro genotoxic effects of the MSG was also investigated on human peripheral lymphocytes by analysing the RAPD-PCR with arbitrary 10-mer primers. The changes occurring in RAPD profiles after MSG treatment include increase or decrease in band intensity and gain or loss of bands. In the comet assay, this additive caused DNA damage at all concentrations in isolated human lymphocytes after 1-h in vitro exposure. Our results demonstrate that MSG is genotoxic to the human peripheral blood lymphocytes in vitro.

Evaluation of the genotoxicity of clomiphene citrate.

Clomiphene citrate (CC) is a selective estrogen-receptor modulator that is primarily used to enhance follicular development in women receiving in vitro fertilization (IVF) treatment. Although some studies suggested large increases in ovarian cancer risk related to fertility medications, this association has not been confirmed in other studies. Whether there could be a residual, small risk is still an open question. It is known that genomic instability and multiple genetic changes may be required in carcinogenesis. Genomic instability such as single-base changes, chromosomal rearrangements or aneuploidy may accelerate this process. Genomic instability is not only central to carcinogenesis, but it is also a factor in some neurodegenerative diseases such as amyotrophic lateral sclerosis or the neuromuscular disease myotonic dystrophy. For these reasons, this study was planned to examine genotoxic effects of CC in human lymphocytes by use of the chromosome aberration (CA) assay, the micronucleus (MN) test, the comet assay, and the test for bacterial mutagenicity in Salmonella typhimurium strains TA98 and TA100 (Ames test). Concentrations of 0.40, 0.80, 1.60, and 3.20μg/ml of CC significantly increased the frequency of chromosomal aberrations (p<0.01 and p<0.001) and micronuclei (p<0.05, p<0.01 and p<0.001) in cultured human lymphocytes, and of DNA damage (tail length, p<0.05, except 0.80μg/ml) in isolated lymphocytes compared with their respective controls. The highest CC concentration at 24h and highest two concentrations after the 48-h treatment significantly decreased the mitotic index. The Ames test showed that the concentrations of CC used in this study induced neither base-pair substitutions nor frame-shift mutations in S. typhimurium strains TA98 and TA100.

Genotoxic effects of chlorophenoxy herbicide diclofop-methyl in mice in vivo and in human lymphocytes in vitro.

Diclofop-methyl (DM) is a chlorophenoxy derivative used in large quantities for the control of annual grasses in grain and vegetable crops. In this study, the genotoxic effects of DM were investigated by measuring chromosomal aberrations (CAs) in mouse bone-marrow cells and CA and the comet assay in human peripheral lymphocytes. Mice were treated with 15.63, 31.25, 62.5, and 125 mg/kg body weight of DM intraperitoneally for 24 hours, and 15.63-, 31.25-, 62.5-, 125-, and 250-µg/mL concentrations were applied to human lymphocytes for both 24 and 48 hours. In in vivo treatments, DM significantly, but not dose dependently, increased the total chromosome aberrations, compared to both negative and solvent controls. Cell proliferation was significantly, but not dose dependently, affected by all doses. In in vitro treatments, DM (except 15.63 µg/mL) significantly and dose dependently increased the frequency of chromosome aberrations. Also, 250 µg/mL of 48-hour treatment was found to be toxic. Cell proliferation was significantly and dose dependently affected by DM applications, when compared to negative control. In in vitro treatments, DM significantly decreased the mitotic index only at the highest concentration for 24 hours, and 62.5- and 125-µg/mL concentrations for 48 hours. In the comet assay, a significant and dose-dependent increase in comet-tail intensity was observed at 62.5-, 125-, and 250-µg/mL concentrations. The mean comet-tail length was significantly increased in all concentrations. Our results demonstrate that DM is genotoxic in mammalian cells in vivo and in vitro.

Evaluation of the genotoxicity of Fusarium mycotoxin moniliformin in human peripheral blood lymphocytes

Mycotoxins are fungal secondary metabolites that can be found in contaminated food and feed. There is some evidence to suggest that certain mycotoxins may be mutagenic. Here, we investigate the genotoxicity of the mycotoxin moniliformin (MON) (3‐hydroxycyclobut‐3‐ene‐1,2‐dione) in human peripheral blood lymphocytes using chromosomal aberration (CA), sister‐chromatid exchange (SCE), and micronucleus (MN) analysis. Lymphocyte cultures were treated for 48 h with six different concentrations of MON between 2.5 and 25 μM. CA, SCE, and MN frequencies were significantly increased in a dose‐dependent manner compared with the negative control. The mitotic, replication, and cytokinesis‐block proliferation indices were not affected by treatment with MON. The results provide evidence to demonstrate that MON can exert cytogenetic effects in human cells in culture. Environ. Mol. Mutagen. 2009.