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Considering the promising previous results of ct-[RuCl(CO)(dppb)(bipy)]PF 6 (where dppb = 1,4-bis(diphenylphosphino)butane and bipy = 2,2'-bipyridine) as an antitumor agent, novel biological assays evaluating its toxicogenic potential were performed. The genotoxicity of the compound was evaluated by the in vitro micronucleus test (V79, Chinese hamster lung fibroblasts; HepG2, hepatocellular carcinoma cells), in vivo bone marrow micronucleus test and comet assay in hepatocytes (Swiss mice). The animals were treated with 0.63, 1.25, 2.5 and 5.0 mg/kg body weight (bw) of the compound. Negative (water) and positive (cisplatin, 1.5 mg/kg bw; methyl methanesulfonate, 40 mg/kg bw) controls were included. The parameters considered in the comet assay were the percentage of tail DNA, tail moment and tail length. The results of the in vitro micronucleus tests showed the absence of genotoxicity in V79 cells, while the compound was genotoxic in HepG2 cells at a concentration of 1.25 μm. In the in vivo micronucleus test, the compound was not genotoxic at the different doses evaluated. In the comet assay, only the dose of 5.0 mg/kg bw resulted in a significant increase in the frequency of DNA damage in hepatocytes when compared to the negative control. The genotoxic effect observed in HepG2 cells and in the liver comet assay indicates that the compound was metabolized by hepatic cells., (© 2018 John Wiley & Sons, Ltd.)

Copaifera lansdorffii Desf. is known as 'copaíba', 'copaiva' or 'paú-de-óleo', and is found in part of Brazil. The present study was undertaken to evaluate the genotoxic potential of C. langsdorffii leaf hydroalcoholic extract (CLE) and its influence on the genotoxicity induced by the chemotherapeutic agent doxorubicin (DXR) using the Swiss mouse peripheral blood micronucleus test. HPLC analysis of CLE using two monolithic columns linked in series allowed quantification of two major flavonoid heterosides, quercitrin and afzelin. Animals were treated with CLE by gavage at doses of 10, 20, 40 and 80 mg kg(-1) body weight per day, each for 20 days. Peripheral blood samples were collected at 24 and 48 h, and 7, 15 and 21 days after the beginning of the treatment. For the antigenotoxicity evaluation, the animals treated with different concentrations of CLE received DXR (15 mg kg(-1) body weight, intraperitoneal) at day 20. The peripheral blood samples were collected 24 and 48 h after the treatment with DXR. The results demonstrated that CLE itself was not genotoxic in the mouse micronucleus assay. In animals treated with CLE and DXR, the number of micronucleus was significantly decreased compared with animals receiving DXR alone. The putative antioxidant activity of one or more of the active compounds of CLE may explain the effect of this plant on DXR genotoxicity., (Copyright © 2012 John Wiley & Sons, Ltd.)

Baccharis dracunculifolia (Asteraceae), the main botanical source of green propolis, is a shrub of the Brazilian 'cerrado'. In folk medicine it is used as an anti-inflammatory agent, mainly for the treatment of gastrointestinal diseases. The aim of the present study was to evaluate the genotoxic and antigenotoxic effects of B. dracunculifolia ethyl acetate extract (Bd-EAE) on Chinese hamster lung fibroblasts (V79 cells) by the comet assay. Methyl methanesulfonate (MMS; 200 microM) was used as an inducer of DNA damage. Genotoxicity was evaluated using four different concentrations of Bd-EAE: 12.5, 25.0, 50.0 and 100.0 microg ml(-1). Antigenotoxicity was assessed before, simultaneously, and after treatment with the mutagen. The results showed a significant increase in the frequency of DNA damage in cultures treated with 50.0 and 100.0 microg ml(-1) Bd-EAE. Regarding its antigenotoxic potential, Bd-EAE reduced the frequency of DNA damage induced by MMS. However, this chemopreventive activity depended on the concentrations and treatment regimens used. The antioxidant activity of phenolic components present in Bd-EAE may contribute to reduce the alkylation damage induced by MMS. In conclusion, our findings confirmed the chemopreventive activity of Bd-EAE and showed that this effect occurs under different mechanism.