Assessment of the cytoprotective effect of the homeopathic compound Canova® on African green monkey kidney (VERO) cell line exposed to the drug dipyrone sodium.

Dipyrone or metamizole is one of the most frequently used analgesic worldwide. Despite its widespread use, this drug may exert genotoxic and cytotoxic effects on lymphocytes. Therefore, studies with therapeutic agents that may provide protection against these effects are important. The homeopathic compound Canova® (CA) appears to be a beneficial candidate for preventing DNA damage and cellular lethality, since this compound acts as an immunomodulator associated with cytoprotective actions. Hence, the aim of the present investigation was to determine the potential cytoprotective effects of CA using cell line VERO as a model. VERO cells were incubated with sodium dipyrone and subsequently subject to the comet, apoptosis and immunocytochemistry assays. Data demonstrated that sodium dipyrone induced an increase in DNA damage index (DI) employing the comet assay. However, when VERO cells were co-treated with CA at the three concentrations studied, a significant reduction in DI was observed, indicating an antigenotoxic effect attributed to CA. Further dipyrone induced an elevation in %apoptosis at 24 and 48 hr. However, when dipyrone was co-incubated with CA, a significant reduction in %apoptosis was noted at the three concentrations of CA employed. Results from immunocytochemical analysis showed a rise in the expression of caspase 8 and cytochrome C when cells were exposed to dipyrone. In contrast, co-treatment of dipyrone and CA significantly reduced the effect of dipyrone. Therefore, evidence indicated that CA acted as an anticytotoxic and antigenotoxic agent counteracting damage induced by dipyrone.

In vitro assessment of cytotoxic, genotoxic and mutagenic effects of antimalarial drugs artemisinin and artemether in human lymphocytes.

Artemisinin is a substance extracted from the Chinese plant Artemisia annua L. widely used in natural medicine for the treatment of various diseases. Artemether is a substance synthesized from artemisinin, and both drugs are commonly administered in the treatment of malaria. Although considered effective antimalarial drugs, very little is known about the genotoxic, cytotoxic and mutagenic effects of these drugs. Therefore, in the present study, we evaluated the genotoxic, mutagenic and cytotoxic effects of artemisinin (12.5, 25 and 50 µg/mL) and artemether (7.46; 14.92 and 29.84 µg/mL) in cultured human lymphocytes using the comet assay, the micronucleus test and the cytotoxicity assay for detection of necrosis and apoptosis by acridine orange/ethidium bromide staining. Our results showed a significant increase (p < 0.05) in the rate of DNA damage measured by comet assay and in the micronucleus frequency after treatment with both drugs. It was also observed that only artemisinin induced a statistically significant increase (p < 0.05) in the number of lymphocytes with death by necrosis 48 h after treatment. The results demonstrated that these two drugs induce mutagenic, genotoxic and cytotoxic effects in cultured human lymphocytes. Our data indicate the need for caution in the use of such drugs, since genotoxic/mutagenic effects may increase the risk of carcinogenesis.

Cytotoxic and Genotoxic Effects of Fluconazole on African Green Monkey Kidney (Vero) Cell Line.

Fluconazole is a broad-spectrum triazole antifungal that is well-established as the first-line treatment for Candida albicans infections. Despite its extensive use, reports on its genotoxic/mutagenic effects are controversial; therefore, further studies are needed to better clarify such effects. African green monkey kidney (Vero) cells were exposed in vitro to different concentrations of fluconazole and were then evaluated for different parameters, such as cytotoxicity (MTT/cell death by fluorescent dyes), genotoxicity/mutagenicity (comet assay/micronucleus test), and induction of oxidative stress (DCFH-DA assay). Fluconazole was used at concentrations of 81.6, 163.2, 326.5, 653, 1306, and 2612.1µM for the MTT assay and 81.6, 326.5, and 1306µM for the remaining assays. MTT results showed that cell viability reduced upon exposure to fluconazole concentration of 1306µM (85.93%), being statistically significant (P<0.05) at fluconazole concentration of 2612.1µM (35.25%), as compared with the control (100%). Fluconazole also induced necrosis (P<0.05) in Vero cell line when cells were exposed to all concentrations (81.6, 326.5, and 1306µM) for both tested harvest times (24 and 48 h) as compared with the negative control. Regarding genotoxicity/mutagenicity, results showed fluconazole to increase significantly (P<0.05) DNA damage index, as assessed by comet assay, at 1306µM versus the negative control (DI=1.17 vs DI=0.28, respectively). Micronucleus frequency also increased until reaching statistical significance (P<0.05) at 1306µM fluconazole (with 42MN/1000 binucleated cells) as compared to the negative control (13MN/1000 binucleated cells). Finally, significant formation of reactive oxygen species (P<0.05) was observed at 1306µM fluconazole vs the negative control (OD=40.9 vs OD=32.3, respectively). Our experiments showed that fluconazole is cytotoxic and genotoxic in the assessed conditions. It is likely that such effects may be due to the oxidative properties of fluconazole and/or the presence of FMO (flavin-containing monooxygenase) in Vero cells.

In vitro assessment of anticytotoxic and antigenotoxic effects of CANOVA(®).

BACKGROUND: CANOVA(®) (CA) is a homeopathic immunomodulator. It contains several homeopathic medicines prepares according to the Brazilian Pharmacopoeia. CA is indicated in clinical conditions in which the immune system is impaired and against tumors. N-methyl-N-nitrosourea (NMU) is an N-nitroso compound, with genotoxic/mutagenic properties. Although several studies have shown promising results in the use of CA, there are no studies reporting possible antigenotoxic effects. METHOD: This study evaluated the in vitro antigenotoxic and anticytotoxic effects of CA in human lymphocytes exposed to NMU. Samples of human lymphocytes that were subjected to different concentrations of a mixture containing CA and NMU were used. The genotoxicity/antigenotoxicity of CA was evaluated by the comet assay, anticytotoxicity was assessed by quantification of apoptosis and necrosis using acridine orange/ethidium bromide. RESULTS: CA significantly reduced DNA damage induced by NMU and reduced significantly the frequency of NMU-induced apoptosis after 24 h of treatment. CONCLUSION: CA has an important cytoprotective effect significantly reducing the DNA damage and apoptosis induced by the carcinogen NMU.