Mutagenicity and genotoxicity of isatin in mammalian cells in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genotoxicity assessment of Garcinia achachairu Rusby (Clusiaceae) extract in mammalian cells in vivo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

In vivo genotoxicity assessment of nerolidol

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genotoxicity testing of Ambelania occidentalis (Apocynaceae) leaf extract in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genotoxicity and mutagenicity of Rosmarinus officinalis (Labiatae) essential oil in mammalian cells in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Genotoxicity assessment of the antimalarial compound artesunate in somatic cells of mice

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vitro genotoxicity assessment of caffeic, cinnamic and ferulic acids

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Antigenotoxicity and antimutagenicity of lycopene in HepG2 cell line evaluated by the comet assay and micronucleus test

Epidemiological studies have provided evidence that high consumption of tomatoes effectively reduces the risk of reactive oxygen species (ROS)-mediated diseases such as cancer. Tomatoes are rich sources of lycopene, a potent singlet oxygen-quenching carotenoid. In addition to its antioxidant properties, lycopene shows an array of biological effects including antimutagenic and anticarcinogenic activities. In the present study, the chemopreventive action of lycopene was examined on DNA damage and clastogenic or aneugenic effects of H2O2 and n-nitrosodiethylamine (DEN) in the metabolically competent human hepatoma cell line (HepG2 cells). Lycopene at concentrations of 10. 25, and 50 mu M, was tested under three protocols: before, simultaneously, and after treatment with the mutagen, using the comet and micronucleus assays. Lycopene significantly reduced the genotoxicity and mutagenicity of H2O2 in all of the conditions tested. For DEN, significant reductions of primary DNA damage (comet assay) were detected when the carotenoid (all of the doses) was added in the cell culture medium before or simultaneously with the mutagen. In the micronucleus test, the protective effect of lycopene was observed only when added prior to DEN treatment. In conclusion, our results suggest that lycopene is a suitable agent for preventing chemically-induced DNA and chromosome damage. (C) 2007 Elsevier Ltd. All rights reserved.

Differential response related to genotoxicity between eggplant (Solanum melanogena) skin aqueous extract and its main purified anthocyanin (delphinidin) in vivo

Anthocyanins are the largest group of water-soluble pigments in the plant kingdom. A number of studies have demonstrated that anthocyanins present antioxidant capacity and show inhibitory effects on the growth of some cancer cells. Thus, the goal of this study was to evaluate both the antimutagenicity/antigenotoxicity and mutagenicity/genotoxicity of aqueous extract obtained from the Solanum melanogena, a possible novel source of anthocyanin, and its main purified anthocyanin extract (delphinidin), using the single cell (comet) assay and micronucleus test. Pretreatment with higher doses of the purified anthocyanin (10 and 20 mg/kg b.w.) led to a statistically significant reduction (p < 0.05) in the frequency of micronuclei in polychromatic erythrocytes induced by cyclophosphamide. The pattern of reduction ranged from 48% to 57% independent of concentration. No apparent: genotoxicity and mutagenicity was found for either the anthocyanin or delphinidin extracts. Taken together, these results suggest that mice pre-treated with specific compounds present in anthocyanins (delphinidin) displayed a lower incidence of mutations induced by cyclophosphamide. This finding emphasizes the potential of natural colorants to prevent mutations and also the applicability of genotoxic evaluation for improving health. Furthermore, the results presented here could be an additional argument to support the use of anthocyanins in the diet. (c) 2006 Published by Elsevier Ltd.

Genotoxicity and cytotoxicity of glass ionomer cements on Chinese hamster ovary (CHO) cells

Glass ionomer cements are widely used in dentistry as restorative materials and adhesives for composite restorations. However, the results of genotoxicity studies using these materials are inconclusive in literature. The goal of this study was to examine the genotoxic and cytotoxic potential of three different glass ionomer cements available commercially (Ketac Cem, Ketac Molar and Vitrebond) by the single cell gel (comet) assay and trypan blue exclusion test, respectively. For this, such materials were exposed to Chinese hamster ovary (CHO) cells in vitro for 1 h at 37 degrees C. Data were assessed by Kruskall-Wallis nonparametric test. The results showed that the powder from Ketac Molar displayed genotoxicity only in the maximum concentration evaluated (100 mu g/mL). In the same way, the liquid from Vitrebond at 0.1% dilution caused an increase of DNA injury. Significant differences (P < 0.05) in cytotoxicity provoked by all powders tested of glass ionomer cements were observed for exposure at 1000 mu g/mL concentration. With respect to liquids of glass ionomer cements evaluated, the major toxic effect on cell viability was produced at 10%, beginning at the dilution of 0.5% for Vitrebond. Taken together, we conclude that some components of glass ionomer cements show both genotoxic and cytotoxic effects.

Antimutagenic effect of Agaricus blazei Murrill mushroom on the genotoxicity induced by cyclophosphamide

Agaricus blazei Murrill extracts have previously been shown to have anticarcinogenic and antimutagenic proper-ties. These results suggest that antimutagenic activity, besides the modulation of the immune system, might be involved in the anticarcinogenic action of A. blazei. To investigate the possible antimutagenic effect of A. blazei in vivo, we evaluated its effect on clastogenicity induced by cyclophosphamide (CP) in mice, using the micronucleus test in bone marrow (MNPCE) and in peripheral blood (MNRET). Male Swiss mice were treated with CP (25 or 50 mg/kg i.p.) or with CP plus mushroom solution at three different temperatures: 4, 21, and 60 degreesC. Aqueous solution of a mixture from various lineages of the mushroom inhibited induction of micronuclei by CP in bone marrow and in peripheral blood of mice. In contrast to the mixture of lineages, a single isolated lineage did not lead to a reduction of CP-induced MN frequencies in either bone marrow or blood cells of mice. The results suggest that under certain circumstances these mushrooms exhibit antimutagenic activities that might contribute to an anticarcinogenic effect. (C) 2001 Elsevier B.V. B.V. All rights reserved.

In vivo genotoxicity evaluation of a treated urban sewage sludge sample

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genotoxicity in primary human peripheral lymphocytes after exposure to radiopacifiers in vitro

Taking into consideration that DNA damage plays an important role in carcinogenesis, the purpose of this study was to evaluate whether some radiopacifiers widely used in clinical practice are able to induce genetic damage in primary human cells in vitro. Human peripheral lymphocytes obtained from 10 healthy volunteers were exposed to barium sulphate (BaSO(4)), zirconium oxide (ZnO(2)) and bismuth oxide (Bi(2)O(3)) at final concentrations ranging from 1 to 1000 mu g/mL for 1 h at 37 degrees C. The negative control group was treated with vehicle control (phosphate buffer solution) for 1 h at 37 degrees C and the positive control group was treated with hydrogen peroxide (at 100 mu M) for 5 min on ice. Results were analyzed by the Friedman non-parametric test. The results pointed all compounds tested out did not induce DNA breakage in human peripheral lymphocytes as depicted by the mean tail moment and tail intensity in all concentrations tested. In summary, our results indicate that exposure to these radiopacifiers may not be a factor that increases the level of DNA lesions in human peripheral lymphocytes as detected by single cell gel (comet) assay.

Allium cepa test in environmental monitoring: A review on its application

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genotoxicity assessment of water soluble fractions of biodiesel and its diesel blends using the Salmonella assay and the in vitro MicroFlow (R) kit (Litron) assay

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)