Genotoxic and antiproliferative properties of Endopleura uchi bark aqueous extract.

The bark extract from Endopleura uchi has been widely used in traditional medicine to treat gynecological-related disorders, diabetes, and dyslipidemias albeit without scientific proof. In addition, E. uchi bark extract safety, especially regarding mutagenic activities, is not known. The aim of this study was to determine the chemical composition, antitumor, and toxicological parameters attributed to an E. uchi bark aqueous extract. The phytochemical constitution was assessed by colorimetric and chromatographic analyzes. The antiproliferative effect was determined using sulforhodamine B (SRB) assay using 4 cancer cell lines. Cytotoxic and genotoxic activities were assessed utilizing MTT and comet assays, respectively, while mutagenicity was determined through micronucleus and Salmonella/microsome assays. The chromatographic analysis detected predominantly the presence of gallic acid and isoquercitrin. The antiproliferative effect was more pronounced in human colon adenocarcinoma (HT-29) and human breast cancer (MCF-7) cell lines. In the MTT assay, the extract presented an IC50 = 39.1 µg/ml and exhibited genotoxic (comet assay) and mutagenic (micronucleus test) activities at 20 and 40 µg/ml in mouse fibroblast cell line (L929) and mutagenicity in the TA102 and TA97a strains in the absence of S9 mix. Data demonstrated that E. uchi bark possesses bioactive compounds which exert cytotoxic and genotoxic effects that might be associated with its antitumor potential. Therefore, E. uchi bark aqueous extract consumption needs to be approached with caution in therapeutic applications.

Bioguided isolation of a selective compound from Calea phyllolepis leaves against breast cancer cells.

Plants of the Calea genus have been reported to contain lipophilic compounds, such as sesquiterpene lactones, with cytotoxic effect against different cancer cell lines. The aim of this manuscript was to investigate the chemical profile and cytotoxic activity of different fractions from Calea phylolepis leaves on different human cancer cell lines. The fractions were prepared using solvent extraction of increasing polarity, yielding hexane, ethyl acetate and methanolic fractions. All fractions were chemically analysed by thin layer chromatography (TLC), and their cytotoxic activity against HT-29 (colon adenocarcinoma), MCF-7 (breast cancer), U-251MG (malignant glioblastoma) and L929 (mouse fibroblast) cell lines was investigated. Among these, the hexane and ethyl acetate fractions showed higher cytotoxic effects, while the methanolic fraction did not show any cytotoxic effects. The major bioactive compound from the hexane fraction (12.15%) was isolated using chromatographic methods and was identified by nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectrometry (GC-MS) analysis as 6-epi-ß-verbesinol coumarate. This compound showed activity against breast cancer cells (IC50 = 5.8 ± 1.0 µg/ml), similar to etoposide. Furthermore, 6-epi-ß-verbesinol coumarate showed low cytotoxicity to normal fibroblast cells, suggesting a high selectivity index (SI = 7.39) against breast cancer cells.

Adaptogenic effects of curcumin on depression induced by moderate and unpredictable chronic stress in mice.

Curcumin has been investigated for the prevention and treatment of diseases due to its anti-oxidant, anti-inflammatory, immunomodulatory, and neuroprotective actions. This current study evaluated the adaptogenic effects of a subchronic oral administration of curcumin to Swiss mice that were submitted to a chronic unpredictable mild stress (CUMS) model of depression. Four groups of mice (vehicle control, CO; curcumin control, COC; CUMS + vehicle, CUMS; CUMS + curcumin, CUMSC) were evaluated for the biochemical parameters. The CUMS model caused depressive-like and anxiety-like behavior in the animals when they were viewed in the Forced Swimming Test and in the Elevated Plus Maze Test. The treatments with curcumin prevented the depressive-like behavior in the Forced Swimming Test and they had anxiolytic effects on the non-stressed animals. This was confirmed by the Elevated Plus Maze Test. Curcumin showed antioxidant effects (IC50 of 38.86 ± 1.78 µg/mL) in the in vitro DPPH (2,2-diphenyl-1-picryl-hydrozole) test. The compound also showed antioxidant effects in vivo, increasing the catalase (CAT) levels in the brains of the stressed animals. The biochemical analyses did not reveal potential renal and hepatic damage. Together, these results have demonstrated the antidepressant and antioxidant effects of curcumin, highlighting in this mice model, the compound's novel adaptogenic potential.

Biotoxicological Analyses of Trimeroside from Baccharis trimera Using a Battery of In Vitro Test Systems.

The use in folk medicine of Baccharis trimera and recent studies on DNA damage by oxidative stress mechanisms have motivated this study. We investigated the biotoxicological effects of trimeroside from this plant. Aqueous extract from aerial parts of B. trimera was fractioned by flash chromatography for further isolation by thin-layer chromatography. The novel nor-monoterpene glycoside, trimeroside, and three flavonoids, cirsimaritin, luteolin and quercetin, were isolated. The genotoxic and mutagenic potential of trimeroside was determined by Salmonella/microsome (TA98 and TA100), comet assay, and cytokinesis-block micronucleus cytome assay (CBMN-cyt) in HepG2 cells. We also screened trimeroside into different human tumoral cell lines by sulforhodamine B (SRB) assay. Mutagenicity was detected in TA100 strain with metabolic activation. Genotoxic effects were not observed in HepG2 by comet assay. However, a decrease in the nuclear index division in the 2.0 mg·mL-1 concentration and an increase of nucleoplasmic bridges in the 1.5 mg·mL-1 concentration were detected by CBMN-cyt assay indicating cytotoxic and mutagenic effects. In SRB assay, trimeroside showed weak antiproliferative activity against the cell lines.

Evaluation of DNA damage in Wistar rat tissues with hyperlipidemia induced by tyloxapol.

Hyperlipidemia is characterized by high levels of plasma triglycerides and LDL-cholesterol, accompanied by reduced HDL-cholesterol levels, and is often associated with an increased risk of cardiovascular diseases. However, few studies have shown the effects of hyperlipidemia on genomic stability. The aim of this study was to evaluate DNA damage provided by tyloxapol induced hyperlipidemia. Tyloxapol, a non-ionic surfactant, which increases the activity of the enzyme HMG-CoA reductase and decreases clearance of lipoproteins, was used to induce hyperlipidemia in Wistar rats. Genomic instability was assessed using the comet assay which evaluates DNA strand breaks in several tissues, and the micronucleus assay in bone marrow to detect chromosomal mutagenicity for clastogenic and/or aneugenic effects. Biochemical analyses confirmed hyperlipidemia in tyloxapol-treated rats, accompanied by hyperglycemia. Higher creatinine and urea levels were observed, suggesting kidney injury. The comet assay indicated increased DNA damage in blood, liver, and kidney, but not in brain tissue. However, no increase in micronucleus frequency was observed, indicating lack of mutagenic effects. Simvastatin, used as lipid lowering drug, decreased cholesterol and triglycerides in rats treated with tyloxapol. Those findings indicate that tyloxapol-induced hyperlipidemia is able to increase genomic instability, which is associated with higher cancer risk. Therefore, this surfactant might be used in models to evaluate new hypolipidemic drugs with associated chemopreventive properties.

Evaluation of DNA Damage in HepG2 Cells and Mutagenicity of Garcinielliptone FC, A Bioactive Benzophenone.

Garcinielliptone FC (GFC) is a polyprenylated benzophenone isolated from the hexanic extract of Platonia insignis seeds with potential pharmacological effects on the central nervous system. In a pre-clinical study, this compound showed anticonvulsant action, becoming a candidate to treat epilepsy disorders. However, genotoxicological aspects of GFC should be known to ensure its safe use. This study investigated the cytotoxic, genotoxic, and mutagenic effects of GFC. Cytotoxicity was evaluated using the colorimetric assay of MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) in human hepatoma cells (HepG2) (2-100 µg/mL) for 3, 6 and 24 hr. The genotoxic and mutagenic potentials were analysed using the alkaline version of the comet assay, the cytokinesis-block micronucleus cytome assay in HepG2 cells, and the Salmonella/microsome assay with the strains TA98, TA97a, TA100, TA102 and TA1535, with and without metabolic activation. GFC concentrations above 50 µg/mL were cytotoxic at all experimental times. Viability of HepG2 cells was higher than 70% after exposure to GFC 2-30 µg/mL for 3 hr in the MTT test. No GFC concentration was mutagenic or genotoxic in the Salmonella/microsome and comet assays. Nuclear division index decreased, indicating the cytotoxic effect of the compound, while micronucleus and nuclear bud frequencies rose after treatment with the highest GFC concentration tested (30 µg/mL). Nucleoplasmatic bridges were not observed. The results indicate that GFC is cytotoxic and mutagenic to mammalian cells, pointing to the need for further studies to clarify the toxicological potentials of this benzophenone before proceeding to clinical studies.

Genotoxic, mutagenic and antigenotoxic effects of Cecropia pachystachya Trécul aqueous extract using in vivo and in vitro assays.

ETHNOPHARMACOLOGICAL RELEVANCE: Cecropia pachystachya is a medicinal plant native to South and Central Americas used to treat asthma and diabetes. AIM OF THE STUDY: In this study, we evaluated the genotoxic, mutagenic and antigenotoxic effects of crude aqueous extract of C. pachystachya (CAE-Cp) leaves. MATERIAL AND METHODS: CAE-Cp was analyzed by the Folin-Ciocalteu method to determine total phenolic and tannin contents. High performance liquid chromatography (HPLC) was used to identify major compounds. Distinct tissues from female and male adult mice were treated with 500-2000mg/kg of CAE-Cp by gavage for the comet assay and micronucleus test analyses. In addition, peripheral blood slides of the group treated with 2000mg/kg CAE-Cp were analyzed 3, 6, and 24h after treatment and were exposed to hydrogen peroxide (ex vivo) to evaluate the genotoxic effect using the comet assay. The Salmonella/microsome assay was carried out against to TA100, TA98, TA97a, TA102, and TA1535 strains in presence and absence of the S9 mix. RESULTS: HPLC showed the presence of chlorogenic acid, isoorientin, orientin, and isovitexin as major compounds. Total phenolic and tannin contents were, respectively, 305.6±0.80 and 144.6±19.04mg of gallic acid equivalent/g of extract. Brain DNA damage was observed in all groups treated with CAE-Cp. The H2O2 challenge indicated genotoxic effect only 6h after the administration of the extract. No increase was detected in micronucleus frequency for any group treated with the extract. Mutagenic effects were detected by Salmonella/microsome assay only in TA102 strain without S9 mix at higher doses. CONCLUSION: The results obtained indicate that CAE-Cp was genotoxic to brain tissue. This result is supported by other papers, showing that compounds present in this extract can cross the blood-brain barrier and act on central nervous system.

Effects of artichoke (Cynara scolymus) leaf and bloom head extracts on chemically induced DNA lesions in Drosophila melanogaster.

The genotoxicity of bloom head (BHE) and leaf (LE) extracts from artichoke (Cynara scolymus L.), and their ability to modulate the mutagenicity and recombinogenicity of two alkylating agents (ethyl methanesulfonate - EMS and mitomycin C - MMC) and the intercalating agent bleomycin (BLM), were examined using the somatic mutation and recombination test (SMART) in Drosophila melanogaster. Neither the mutagenicity nor the recombinogenicity of BLM or MMC was modified by co- or post-treatment with BHE or LE. In contrast, co-treatment with BHE significantly enhanced the EMS-induced genotoxicity involving mutagenic and/or recombinant events. Co-treatment with LE did not alter the genotoxicity of EMS whereas post-treatment with the highest dose of LE significantly increased this genotoxicity. This enhancement included a synergistic increase restricted to somatic recombination. These results show that artichoke extracts promote homologous recombination in proliferative cells of D. melanogaster.

Evaluation of mutagenic and genotoxic activities of lobeline and its modulation on genomic instability induced by ethanol.

AIM: Lobeline is a natural alkaloid derived from Lobelia inflata that has been investigated as a clinical candidate for the treatment of alcoholism. In a pre-clinical trial, lobeline decreased the preference for and consumption of ethanol, due to the modulation of the nicotinic acetylcholine receptor. However, the interaction between lobeline and ethanol is poorly known and thus there are safety concerns. The present study was conducted to evaluate the mutagenic and genotoxic effects of lobeline and assess its modulation of ethanol-induced toxicological effects. MAIN METHODS: CF-1 male mice were divided into five groups. Groups received an intraperitoneal injection of saline solution, lobeline (5 or 10mg/kg), ethanol (2.5 g/kg), or lobeline plus ethanol, once a day for three consecutive days. Genotoxicity was evaluated in peripheral blood using the alkaline comet assay. The mutagenicity was evaluated using both Salmonella/microsome assay in TA1535, TA97a, TA98, TA100, and TA102 Salmonella typhimurium strains and the micronucleus test in bone marrow. Possible liver and kidney injuries were evaluated using biochemical analysis. KEY FINDINGS: Lobeline did not show genotoxic or mutagenic effects and did not increase the ethanol-induced genotoxic effects in blood. Lobeline also protected blood cells against oxidative damage induced by hydrogen peroxide. Biochemical parameters were not altered, indicating no liver or kidney injuries or alterations in lipid and carbohydrate metabolisms. SIGNIFICANCE: These findings suggest that lobeline does not induce gene or chromosomal mutations, and that this lack of genetic toxicity is maintained in the presence of ethanol, providing further evidence of the safety of this drug to treat alcohol dependence.

Baccharis trimera (Less.) DC as genotoxicity indicator of exposure to coal and emissions from a thermal power plant.

During coal combustion, hazardous elements are discharged that impair environmental quality. Plant cover is the first available surface for the atmospheric pollutants in terrestrial ecosystems. The aim of this study was to evaluate genotoxicity in the aqueous extract of the native plant, Baccharis trimera, exposed to coal and emissions from a thermal power plant (coal-fired power plant in Candiota, Brazil), correlating seasonality, wind tunnel predominance, and presence of inorganic elements. The presence of inorganic elements in the aerial parts of B. trimera was analyzed by particle-induced X-ray emission (PIXE) spectrometry, and genotoxicity was evaluated by ex vivo comet assay. The genotoxic effects of aqueous extracts of B. trimera from four sites located in the area around power plant were analyzed by comet assay in peripheral human lymphocytes. Winter samples showed greater levels of metals than summer samples. Genotoxicity was detected in B. trimera extracts collected from the region exposed to extraction and burning coal. Extracts from the site impacted by the dominant wind induced more damage to DNA than those from other sites. Based on our data, we can suggest that in winter the inorganic elements from extraction and burning of coal and carried through the wind tunnel were responsible for the genotoxicity observed in aqueous extract of B. trimera.

Cytotoxic and leishmanicidal properties of garcinielliptone FC, a prenylated benzophenone from Platonia insignis.

Garcinielliptone FC (GFC), a natural prenylated benzophenone, was extracted from Platonia insignis Mart. (Clusiaceae), a native plant commonly known as bacuri and used in traditional Brazilian medicine for the treatment of skin diseases. The aim of this study was to evaluate the cytotoxic and leishmanicidal effects of GFC using in vitro models. The experimental data demonstrated that the polyisoprenylated benzophenone GFC possesses cytotoxic and leishmanicidal activities.

Antigenotoxic effect of acute, subacute and chronic treatments with Amazonian camu-camu (Myrciaria dubia) juice on mice blood cells.

Myrciaria dubia, a plant native to the Amazon region, stands out as a fruit rich in vitamin C and other metabolites with nutritional potential. We evaluated the antioxidant, genotoxic and antigenotoxic potential of M. dubia juice on blood cells of mice after acute, subacute and chronic treatments. Flavonoids and vitamin C present in the fruit of M. dubia were quantified. In vitro antioxidant activity was evaluated by DPPH assay. Blood samples were collected for analysis after treatment, and the alkaline comet assay was used to analyze the genotoxic and antigenotoxic activity (ex vivo analysis using H(2)O(2)). The amount of vitamin C per 100mL of M. dubia was 52.5mg. DPPH assay showed an antioxidant potential of the fruit. No M. dubia concentration tested exerted any genotoxic effect on mice blood cells. In the ex vivo test, the juice demonstrated antigenotoxic effect, and acute treatment produced the most significant results. After the treatments, there was no evidence of toxicity or death. In conclusion, our data show that M. dubia juice has antigenotoxic and antioxidant activities, though with no genotoxicity for blood cells. Nevertheless, more in-depth studies should be conducted to assess the safety of this fruit for human consumption.

Genotoxicity evaluation of three benzopyrans from Hypericum polyanthemum.

In the present study we used the micronuclei test and the comet assay in mice to investigate the genotoxic and mutagenic effects of three benzopyrans--6-isobutyryl-5,7-dimethoxy-2,2-dimethyl-benzopyran (HP1); 7-hydroxy-6-isobutyryl-5-methoxy-2,2-dimethyl-benzopyran (HP2); and 5-hydroxy-6-isobutyryl-7-methoxy-2,2-dimethyl-benzopyran (HP3)--isolated from Hypericum polyanthemum. No significant difference in polychromatic erythrocyte (PCE) percentage between the vehicle group and groups treated with HP1, HP2, or HP3 was detected, indicating no toxicity to the bone marrow of the animals. Only HP1 increased the frequency of micronucleated cells (MNPCEs) in bone marrow sampled after 24 h in comparison with the vehicle group, suggesting a weak mutagenic effect. The damage index and damage frequency did not show a significant increase after treatment with HP1, HP2, or HP3 in comparison with the vehicle group. The antitumor activity previously reported in vitro for these benzopyrans, the lack of acute toxicity, the MN induction only for HP1, and the relatively low DNA damage make all compounds good candidates for in vivo studies on antitumor action.