Effects of Reverse Transcriptase Inhibitors on Proliferation, Apoptosis, and Migration in Breast Carcinoma Cells.

High telomerase activity in human breast cancer is associated with aggressive tumors resulting in decreased survival. Recent studies have shown that telomerase inhibitors may display anticancer properties in some human cancer cell lines. In the present study, we examined the effects of 4 reverse transcriptase inhibitors (RTIs), used for the treatment of HIV; Abacavir (AC), Lamivudine (LV), Stavudine (SV), and Tenofovir (TF) on proliferation, apoptosis, and migration in the normal human mammary epithelial cell line, hTERT-HME1, and the human breast cancer cell line, MCF-7. Cells were treated with AC, LV, SV, or TF alone or in combination with paclitaxel (PAC), a known drug used to treat breast cancer. Conduct of the thiazolyl blue tetrazolium bromide assay demonstrated that AC, SV, and TF had stronger cytotoxic effects on MCF-7 cells than in hTERT-HME1 cells. The combined treatment of RTIs and PAC caused high rates of cell death in MCF-7 and low rates of cell death in HTERT-HME1 by apoptosis. The percentages of apoptotic cells in the treatment of AC and SV in combination with PAC for 48 and 72 hours were higher than PAC. Significantly increased apoptosis and decreased migration levels were found in MCF-7 cells treated with AC and co-treatment of AC+PAC or SV+PAC than HME1 cells. These treatments can also prevent migration capacity more than PAC. Therefore, a combination strategy based on telomerase inhibitors such as AC or SV and anticancer drugs may be more effective in the treatment of certain breast cancers.

Co-exposure to deltamethrin and thiacloprid induces cytotoxicity and oxidative stress in human lung cells.

Deltamethrin (DEL) and thiacloprid (THIA) are commonly used synthetic insecticides in agriculture either separately or in combination. There is limited information in human cells for the effects of the mixture of DEL + THIA on oxidative stress. Therefore, the present study was designed to examine the effects of the mixture on cell proliferation and oxidative stress in human lung fibroblast cells. Human telomerase reverse transcriptase (hTERT)-expressing human lung fibroblasts, WTHBF-6 cells, were treated with 2.5 + 37.5, 5 + 75, 12.5 + 187.5, and 25 +375 µM concentrations of DEL + THIA for the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and 5 + 75, 12.5 + 187.5, and 25 + 375 µM for lipid peroxidation and reduced glutathione (GSH) assays for 24, 48, and 72 h in the absence and presence of metabolizing fractions of the mammalian liver (S9 mixture). Both the mixture of DEL + THIA and their metabolites significantly reduced cell viability and induced cytotoxicity in WTHBF-6 cells, especially at higher concentrations. The mixture of DEL + THIA significantly decreased GSH levels at the highest concentration for all treatment times and at the highest two concentrations (12.5 + 187.5 and 25 + 375 µM) for 72 h in the presence of S9 mixture. The highest concentration of DEL + THIA mixture caused a significant increase in malondialdehyde (MDA) level at 72 h in the absence of S9 mixture. There were also significant increases in MDA levels at the highest concentration for 48-h and all concentrations of DEL + THIA for 72-h treatment in WTHBF-6 cell cultures with S9. These data showed that the mixture of DEL + THIA and their metabolites can induce cytotoxicity and oxidative stress in human lung fibroblasts.

Cytogenetic alterations induced by flupyradifurone, a new butenolide insecticide, in human lymphocytes.

Flupyradifurone (FPD), a member of the new class of butenolide insecticides, acts on nicotinic acetylcholine receptors. Studies on genotoxic and carcinogenic effects of FPD are very limited. This is the first study to investigate the cytotoxic and genotoxic effects of FPD and its metabolites on human lymphocyte cultures with or without a metabolic activation system (S9 mix) using chromosomal aberration (CA) and micronucleus (MN) tests. The cultures were treated with 85, 170, and 340 µg/ml of FPD in the presence (3 h treatment) and absence (48 h treatment) of S9 mix. Dimethyl sulfoxide (DMSO) was used as a solvent control. Statistically significant decreases were detected at the medium and highest concentrations for 48 h treatments while decreases in mitotic index (MI) in the presence of the S9 mix were found statistically significant at all FPD concentrations tested when compared with the solvent control. FPD also decreased the nuclear division index (NDI) at the highest concentration (340 µg/ml) in the absence of S9 mix. When compared with the solvent control, increases in CA frequencies were significant at the medium and highest concentrations. Significantly increased MN frequency was only found at the highest FPD concentration in cultures without S9 mix compared with the solvent control while increases in the MN frequencies in the presence of S9 mix were statistically significant at all FPD concentrations. The results of the present study indicate that FPD and its metabolites can show cytotoxic and genotoxic effects in human lymphocytes. More genotoxicity studies are necessary to make a possible risk assessment in humans.

Cytogenetic effects of commercial formulations of deltamethrin and/or thiacloprid on Wistar rat bone marrow cells.

Deltamethrin (DEL) and thiacloprid (THIA) are two insecticides that are widely used in agriculture either separately or in combination. Studies on genotoxicity and cytotoxicity of TIA and the mixture of DEL and THIA insecticides have not been reported so far. Therefore, we investigated the cytotoxic and genotoxic effects of commercial formulations DEL and/or THIA in rat bone marrow cells, using mitotic index (MI), micronucleus (MN) and chromosome aberrations (CA) assay. In vivo cytokinesis-block micronucleus (CBMN) assay using cytochalasin-B in bone marrow cells was performed for the first time in this study. Rats were orally gavaged with a single dose of DEL (15 mg/kg), THIA (112.5 mg/kg) or DEL + THIA (15 + 112.5 mg/kg) for 24 h (acute treatments), or DEL (3 mg/kg/day), THIA (22.5 mg/kg/day) or DEL + THIA (3 + 22.5 mg/kg/day) for 30 days (subacute treatments). A corn oil vehicle control group and cyclophosphamide (50 mg/kg) positive control group were also included. All DEL and/or THIA treatments significantly decreased MI and binucleated (BN) cell numbers, and significantly increased CA, as compared to the vehicle control group. The results of CBMN assay indicated that the combination of DEL and THIA for both treatment times and the 30-day treatment with THIA alone caused a significant increase in micronucleus formation in BN cells. The present findings indicated the combined exposure of DEL and THIA showed genotoxic and cytotoxic effects more than those of individual exposure of DEL or THIA in rat bone marrow cells.

Effects of Viscum album L. extract and quercetin on methotrexate-induced cyto-genotoxicity in mouse bone-marrow cells.

Viscum album, a semi-parasitic plant, has been used both in traditional and supplementary medicine in the treatment of many diseases. Quercetin (QE), one of the major flavonoids in some fruits and vegetables, has anti-oxidative and anti-carcinogenic activities. Methotrexate (MTX), an anti-folate anti-metabolite, is a widely used anti-neoplastic drug with significant clastogenic effects. The aim of this study was to investigate the anti-cytogenotoxic effects of pre-treatment with V. album extract (VAE) and QE on MTX-induced chromosomal aberrations (CAs) in mouse bone-marrow cells. Pre-treatment of mice by gavage with VAE (250mg/kgbw/day for 10 days) and QE (50mg/kgbw/day for 10 days) caused a significant decrease in CAs and in the number of aberrant cells with CAs induced by intramuscular treatment of the mice with MTX (10mg/kgbw/day for 3 days), when compared with the group treated with MTX alone. These compounds also significantly increased the mitotic index (MI) in bone-marrow cells that had been suppressed by MTX. In conclusion, from the findings we suggest that VAE and QE may play a role in reducing cyto-genotoxicity induced by anti-neoplastic drugs during cancer chemotherapy.

Cytotoxic and genotoxic effects of high-frequency electromagnetic fields (GSM 1800 MHz) on immature and mature rats.

We investigated the cytogenotoxic effects of high frequency electromagnetic fields (HF-EMF) for 45 day and the effect of a recovery period of 15 day after exposure to EMF on bone marrow cells of immature and mature rats. The animals in treatment groups were exposed to 1800 MHz EMF at SAR of 0.37 W/kg and 0.49 W/kg for 2h/day for 45 day. Two recovery groups were kept for a recovery period of 15 day without EMF after exposure to HF-EMF. Two control groups for both immature and mature rats were also included. Significant differences were also observed in chromosome aberrations (CA), micronucleus (MN) frequency, mitotic index (MI) and ratio of polychromatic erythrocytes (PCEs) in all treatment groups. The cytogenotoxic damage was more remarkable in immature rats and, the recovery period did not improve this damage in immature rats. Because much higher and irreversible cytogenotoxic damage was observed in immature rats than in mature rats, further studies are needed to understand effects of EMF on DNA damage and DNA repair, and to determine safe limits for environment and human, especially for children.

Genotoxic and cytotoxic effects of doxycycline in cultured human peripheral blood lymphocytes.

Doxycycline (DOX) is a broad-spectrum tetracycline antibiotic used in the treatment of many infections. In this study, the genotoxic and cytotoxic effects of DOX in cultured human peripheral blood lymphocytes were investigated by measuring chromosome aberrations (CAs), cytokinesis-block micronucleus (CBMN) assay, mitotic index (MI), and nuclear division index (NDI). Cultures were treated with DOX at three concentrations (2, 4, and 6 µg/mL) for 48 hours. Mitomycin C (MMC) was used as a positive control. All the tested concentrations of DOX for MI and the higher concentrations (4 and 6 µg/mL) for NDI significantly decreased mitotic activity. However, there are no significant differences between negative control and all the tested concentrations of DOX for CA and MN frequencies. In conclusion, our results indicate that DOX has a cytotoxic effect, but not a genotoxic effect, on human peripheral blood lymphocyte cultures. Further detailed studies, especially about the cell-cycle kinetics of DOX, are required to elucidate the decreases in dividing cells and make a possible risk assessment on cells of patients receiving therapy with this drug. Further, if the specific cytostatic and cytotoxic potential of DOX to different types of cancer cells is investigated in detail, it may also have been used as an antitumoral drug.

Amoebicidal and Amoebistatic Effects of Artemisia argyi Methanolic Extracts on Acanthamoeba castellanii Trophozoites and Cysts.

PURPOSE : The present study aimed to investigate the amoebicidal and amoebistatic efects of Artemisia argyi leaf methanolic extract by testing the effects on trophozoites and on cysts. We also determined cytotoxic effect, enzymatic and non-enzymatic antioxidant activities, total phenolic, lavonoid and antioxidative contents of A. argyi. METHODS: A. argyi was harvested from various geographic sites in Ordu province in Turkey. The fresh leaves were subjected to methanolic extraction. In 100 µl culture, different concentrations of A. argyi methanolic extract (in quantities from 1.2, 2.3, 4.7, 9.4, 18.7, 37.4, 74.8 mg/ml) and the same volume of trophozoite/cyst suspension were mixed for the determination of the amoebicidal activity of the plant extract. Human bronchial epithelial cells were treated with the same concentrations of Artemisia extracts to determine cytotoxic potential. RESULTS: Total phenolic and lavonoid contents of the extract were calculated as 261 mg gallic acid/g dry extract and 29 mg quercetin/g dry extract, respectively. Total antioxidant activity was also calculated as 367 mg ascorbic acid/g dry extract. The growth of trophozoites stopped in A. argyi methanolic extract with 50% inhibitory concentrations (IC50)/8 h for 37.4 mg/ ml and 74.8 mg/ml extract solution and had stronger amoebicidal activity on the cysts with IC50/72 h. Artemisia showed stronger inhibitory effects on bronchial epithelial cells at the concentrations of 9.4, 18.7, 37.4 and 74.8 mg/ml. CONCLUSION: The study indicated that A. argyi leaf extract has cytotoxic and anti-amoebic activities.

Argan oil reduces oxidative stress, genetic damage and emperipolesis in rats treated with acrylamide.

Acrylamide (AA), a well-known toxicant, is present in high-temperature-processed foods in heated foods. Argan oil (AO), a natural vegetable oil, is receiving increasing attention due to its powerful biological properties. However, limited information is available about its effects in lymphoid organs and bone marrow. The aim of this study is to investigate the effects of AO on hematological parameters, 8-hydroxydeoxyguanosine (8-OHdG), thiobarbituric acid reactive substances (TBARs), protein carbonyl (PCO), glutathione (GSH), myeloperoxidase (MPO) levels, the formation of micronucleus (MN) and megakaryocytic emperipolesis (ME) against AA-induced toxicity in rats. The animals were treated with AA (50mg/kg/day), AO (6ml/kg/day per day) and AA+AO (50mg+6ml/kg/day) for 30days. Treatment of rats with AA significantly decreased the hematological parameters, GSH and MPO activity and PCEs ratio while it increased TBARs, PCOs and 8-OHdG levels and formation of MN and ME. No significant differences were observed in the animals received the AO alone. Co-treatment with AA+AO ameliorated almost all of the alterations caused by AA and exhibited protective effect in rats. Based on the obtained results, we suggest that integration of AO in diet or using its supplements may be a good strategy for improving tissue injury in many diseases.

Viscum album L. extract and quercetin reduce cyclophosphamide-induced cardiotoxicity, urotoxicity and genotoxicity in mice.

Possible protective effects of a methanolic extract of Viscum album (VA) and quercetin (QE) against cyclophosphamide (CP) induced cardiotoxicity, urotoxicity and genotoxicity in mice were evaluated. Mice were administered orally VA (250 mg/kg/day) and QE (50 mg/kg/day) for 10 days alone or in combination with CP. After the same doses of VA and QE given for 7 days, rats were intraperitoneally administered CP (40 mg/kg) on days 8 and 9 of the experiment. Cardiotoxic, urotoxic and genotoxic effects were examined in serum, heart, bladder and bone marrow. Significant decreases in the levels of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase), glutathione-S-transferases, reduced glutathione and mitotic index were observed. QE completely and VA partly ameliorated almost of all the examined parameters when given together with CP. Higher total nitrate/nitrite levels were observed in the myocardial tissue treated with QE and VA in combination with CP. In addition, the pre-treatment with VA and QE together with CP significantly decreased chromosome aberrations and aberrant cells compared to CP alone. Results from the current study suggest that QE and VA supplementation attenuates CP induced cardiotoxicity, urotoxicity and genotoxicity through a mechanism related to their ability to decrease oxidative stress and inflammation, and at least in part to its protective effects on the cardiovascular system. In addition, VA and QE may play a role in reducing cytogenotoxicity induced by anti-neoplastic drugs during cancer chemotherapy.

Evaluation of the genotoxicity and cytotoxicity of fexofenadine in cultured human peripheral blood lymphocytes.

Fexofenadine (FXF) is a new non-sedating antihistamine used in the treatment of seasonal allergic rhinitis and chronic idiopathic urticaria. Studies on FXF genotoxicity and cytotoxicity in cultured human peripheral blood lymphocytes have not been reported so far. Therefore, the present study is the first report investigating the genotoxic and cytotoxic effects of FXF in cultured human peripheral blood lymphocytes in vitro. Cultures were treated with FXF at three concentrations (50, 100 and 150 µg/ml) for 24 and 48 h. Endpoints analyzed included: mitotic index (MI), nuclear division index (NDI), chromosomal aberrations (CA) and micronucleus (MN) assay. Mitomycin C (MMC) was used as a positive control. The results of CA and MN assays showed that FXF was not genotoxic at all the concentrations tested, meanwhile MI and NDI results showed dose-dependent decrease and significant differences were found for at least one concentration. In conclusion, the results of this study suggest that FXF has a cytotoxic effect but not genotoxic effect on human peripheral blood lymphocyte cultures. Further cytogenetic studies, especially about the cell cycle kinetics of FXF are required to elucidate the decreases in dividing cells, and biomonitoring studies should also be conducted with patients receiving therapy with this drug.

[Diagnosis of protozoa by loop-mediated isothermal amplification: (LAMP)]. / Protozoonlarin tanisinda ilmige Dayali Izotermal Çogaltma Yöntemi (LAMP).

Plasmodium, Isospora, Toxoplasma, Babesia and Cryptosporidium are parasites which have a significant role in human health. The location in which the protozoon settles in the body, the way that it leaves the host, and the sample which is send from the clinic are the elements of the general methods used in the diagnosis of the ailments caused from protozoan. Classical methods are not adequate for the identification of some protozoon; also, molecular methods have to be used in designating the distinctions between the species. In recent years, one of the molecular methods which has been used frequently in the identification of protozoon is the technique of LAMP. With the aid of the LAMP technique, from which it is possible to obtain reliable outcomes without the contribution of technical skills and professional equipment, in constant temperature it is possible to have a great number of copies from the targeted DNA in a short period. The aim of this collation is to give information about the usage of the technique of LAMP in the identification of the protozoa which are important for human health and the comparison between the technique of LAMP and other molecular methods.