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Nickel-based nanoparticles (NPs) are new products with an increasing number of industrial applications that were developed in recent years. NiO NPs are present in several nanotechnological industrial products, and the characterization of their genotoxic potential is essential. The present study assessed the genotoxicity of NiO NPs in vivo and in vitro using the somatic mutation and recombination test in somatic cells of Drosophila melanogaster (SMART), the cytokinesis - block micronucleus assay (CBMN), and the comet assay in a V79 cell line. The NiO NPs used in this study were about 30 nm in mean size. Larvae of Drosophila melanogaster were exposed to 5 mL of five different concentrations (1.31, 2.62, 5.25, 10.5, and 21 mg/mL) of NiO NPs. In turn, V79 cells were treated with a concentration range of 15-2000 μg/mL NiO NPs. The SMART showed that all concentrations of NiO NPs are genotoxic to the standart (ST) cross when compared to the negative control. On the other hand, only the highest concentration (21 mg/mL) was genotoxic to the HB cross. Somatic recombination was the preferential mechanism lesions were induced in D. melanogaster. The results show that NiO NPs were mutagenic to V79 cells as assessed by the CBMN assay. Significant differences in the frequencies of micronuclei (MN) were observed using the highest NiO NP concentrations (250 and 500 μg/mL) in the 4- and 24-h treatments, but when 125 μg/mL NiO NPs was used, such difference was observed only in the 4-h exposure time. The comet assay revealed that 62, 125, 250 and 500 μg/mL NiO NPs induced a significant increase in DNA damage. The results observed in this study indicate that NiO NPs are genotoxic and mutagenic in vitro and in vivo., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Propolis is a resinous, complex mixture of compounds collected by the bee species Apis mellifera. This study investigated the genotoxicity of green and brown propolis collected in southeast Brazil using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. The effect of five concentrations (0.5, 1.0, 2.0, 4.0, and 7.5 mg/mL) of both propolis types was analyzed in standard (ST) and high-bioactivation (HB) crosses, which have normal and high levels of cytochrome P450 enzymes, respectively. The results show that the types of propolis evaluated have no mutagenic action, in either cross. Moreover, chromatography findings revealed that the propolis types analyzed have different chemical compositions. Brown propolis had lower levels of polyphenols (∼7.2 mg/mL), compared to the green type (34.9 mg/g). Taken together, the findings of the present study and literature reports point to the safety in consuming low amounts of propolis, considering the risk of genetic damage, and confirm the absence of mutagenic and recombinagenic actions of the propolis types investigated., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The somatic mutation and recombination test in Drosophila melanogaster was applied to analyze the mutagenic and recombinagenic activity of the chemotherapeutic drugs cisplatin, paclitaxel, and 5-fluorouracil, comparing the effects observed in combinatory treatments with those observed in single administrations. The results obtained in two different genotypes allowed to quantitatively and qualitatively estimate the contribution of genotoxic effects. The results obtained with the individual drug treatments showed that cisplatin and 5-fluorouracil were genotoxic, being able to increase the frequency of total spots on both genotypes. While cisplatin preferentially induced DNA damage of recombinational origin, all the damages induced by 5-fluorouracil were caused by gene and/or chromosome mutations, and the aneuploidogenic compound paclitaxel was not genotoxic. The combination of these drugs does not exert a synergist genotoxic effect in both genotypes compared to the single-agent administration. Instead, it was observed a modification in the proportion of mutation and recombination to the final genotoxicity observed. The antiproliferative activity of PAC could be responsible for the non-synergic genotoxic effect observed. Based on our results it is possible to suggest that cisplatin/paclitaxel/5-fluorouracil treatment regimen cannot impose a higher risk of the development of genotoxicity-associated secondary tumors in comparison to their individual applications., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

This study characterizes the likely interaction of surface water and sediment samples with DNA to quantitatively and qualitatively establish their mutagenic and/or recombinagenic activity. Samples were collected at 5 different sites within the area of Araçá Stream and 2 different sites within the Sinos River mouth and Garças Stream in the municipality of Canoas, RS, Brazil. The area is impacted by untreated urban discharges (sites 1-7), agricultural pesticides (sites 5 and 7), hospital waste (site 3), animal dejects (site 5), small industries (sites 4, 5 and 6) and vehicular discharges (sites 2, 4, 5 and 6). The wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster was used. The test detects simultaneously mutations and recombination induced by the activity of genotoxins of direct and indirect action. All the samples displayed a massive recombinagenic response, but no mutagenic activity was detected in any of the evaluated samples. This study was done in D. melanogaster with unprocessed water and sediment samples attributing a massive and exclusive recombinagenic action associated to the induction of homologous recombination--a genetic phenomenon involved in the loss of heterozygosity.

In this study, the widespread environmental pollutants 1-nitronaphthalene (1NN), 1,5-dinitronaphthalene (1,5DNN), 2-nitrofluorene (2NF) and 9-nitroanthracene (9NA), were investigated for genotoxicity in the wing somatic mutation and recombination test (SMART) of Drosophila--using the high bioactivation (HB) cross. Our in vivo experiments demonstrated that all compounds assessed induced genetic toxicity, causing increased incidence of homologous somatic recombination. 2NF, 9NA and 1NN mutant clone induction is almost exclusively related to somatic recombination, although 1,5DNN-clone induction depends on both mutagenic and recombinagenic events. 1NN has the highest recombinagenic activity (approximately 100%), followed by 2NF (approximately 77%), 9NA (approximately 75%) and 1,5DNN (33%). 1NN is the compound with the strongest genotoxicity, with 9NA being approximately 40 times less potent than the former and 2NF and 1,5DNN approximately 333 times less potent than 1NN. The evidence indicating that the major effect observed in this study is an increased frequency of mitotic recombination emphasizes another hazard that could be associated to NPAHs--the increment in homologous recombination (HR).