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.

Toxicological potential of Aloysia gratissima: Insights from chemical analysis and in vitro studies

ETHNOPHARMACOLOGICAL RELEVANCE

Aloysia gratissima leaves are popularly used to treat respiratory, digestive, and nervous system disorders. Several studies have been carried out to determine the biological activity of A. gratissima, such as its antibacterial and anti-edematogenic activities, but despite the beneficial uses of A. gratissima, few studies have examined the toxicological profile of this plant.

AIM OF THE STUDY

This study aimed to determine the chemical composition, cytotoxic, genotoxic, mutagenic potential, and antioxidant activity of an aqueous extract of A. gratissima leaves (AG-AEL).

MATERIAL AND METHODS

The phytochemical constitution of AG-AEL was assessed by colorimetric analyses and High-performance liquid chromatography (HPLC). The inorganic elements were detected by Particle-Induced X-ray Emission (PIXE). The antioxidant, cytotoxicity, genotoxic, and mutagenic activities were evaluated in vitro by Di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH), Sulforhodamine B (SRB) assay, comet assay, and Salmonella/microsome assays.

RESULTS

AG-AEL indicated the presence of terpenoids, flavonoids, and phenolic acids. HPLC detected rutin at 2.41 ± 0.33 mg/100 mg. PIXE analysis indicated the presence of Mg, Si, P, S, K, Ca, Mn, and Zn. The 50% inhibitory concentration was 84.17 ± 3.17 μg/mL in the DPPH assay. Genotoxic effects were observed using the Comet assay in neuroblastoma (SH-SY5Y) cells and mutations were observed in TA102 and TA97a strains. The extract showed cytotoxic activities against ovarian (OVCAR-3), glioblastoma (U87MG), and colon (HT-29) cancer cell lines.

CONCLUSIONS

In conclusion, AG-AEL increased DNA damage, induced frameshift, and oxidative mutations, and showed cytotoxic activities against different cancer cells. The in vitro toxicological effects observed suggest that this plant preparation should be used with caution, despite its pharmacological potential.

Protective effect of Hovenia dulcis Thunb. leaf extracts against ethanol-induced DNA damage in SH-SY5Y cells

ETHNOPHARMACOLOGICAL RELEVANCE

Hovenia dulcis Thunb. has been used as a medicinal herb for the treatment of hepatic diseases and alcohol intoxication.

AIM OF THE STUDY

The genotoxic effect and the antigenotoxic potential of ethanolic extract of H. dulcis leaves and its methanolic fraction were evaluated against ethanol-induced damages in SH-SY5Y cells.

MATERIALS AND METHODS

The phytochemical analysis and antioxidant activity of H. dulcis extracts were also assessed. In addition, a systems biology analysis was performed to investigate the molecular pathway of action of the H. dulcis leaves compounds.

RESULTS

The ethanolic extract and its methanolic fraction presented genotoxicity through comet assay at 0.5 and 0.25 mg/mL. On the other hand, both extracts showed protective action against ethanol at all concentrations. Additionally, an NBT assay was performed and demonstrated an ability of the extracts to reduce superoxide anion formation when SH-SY5Y cells were challenged with ethanol. HPLC analysis indicated the presence of quercitrin, isoquercitrin, and rutin. Further, system biology assays indicated a molecular action pathway, where the compounds from the leaves of H. dulcis, in addition to performing free radical scavenging activity, activate PP2A, and may inhibit the apoptosis pathway activated by ethanol-induced oxidative stress.

CONCLUSIONS

This work is important to indicate potential antigenotoxic and antioxidant properties of H. dulcis leaves, and its use can be investigated against DNA damage induced by ethanol.

Antimicrobial activity of dimeric acylphloroglucinols isolated from southern Brazilian Hypericum species against to resistant bacterial

The hexanic extracts of Hypericum austrobrasiliense, H. caprifoliatum, H. denudatum, H. pedersenii and H. polyanthemum, and three isolated dimeric acylphloroglucinols (uliginosin B, japonicine A and hyperbrasilol B) were assayed for their antimicrobial activity against some Gram-positive and Gram-negative bacteria (including resistant strains). These extracts were assayed using the disc diffusion test, and the results indicated that the tested species did non exhibit activity on the Gram-negative strains. Subsequently, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were measured using the broth dilution technique adopted to macrodillution. The most susceptible strains were the MRSA and the S. aureus MLSb. Regarding these pathogens, the better MIC values were obtained with the extracts from H. austrobrasiliense, H. caprifoliatum and H. pedersenii. The acylphloroglucinols uliginosin B and hyperbrasilol B presented the lowest MIC values against Enterococcus faecalis, Staphylococcus aureus, MRSA and S. aureus MLSb resistance.

Baccharis trimera aqueous extract modulates inflammation and nociception in mice

Background

The aerial parts of Baccharis trimera (Less.) are frequently used as a tea to treat several diseases. Therefore, the aim of this study was to identify the constituents of an aqueous extract of B. trimera, focusing on their antioxidant, anti-inflammation, and antinociception activities and properties. For that, the researchers performed in vivo assays using the formalin test and Freund’s Complete Adjuvant (FCA) to measure the acute and chronic inflammatory pain in mice. Moreover, the myeloperoxidase enzyme (MPO) was analyzed in the subcutaneous tissue after the FCA injection, together with the counting of lymphocytes in the peripheral blood of the mice.

Results

The qualitative phytochemical analysis indicated the presence of flavonoids and saponins in the B. trimera aqueous extract. The high-performance liquid chromatography (HPLC) analyses showed the presence of phenolic compounds, such as chlorogenic acid, ellagic acid, rosmarinic acid, as well as flavonoids, such as rutin, quercetin, and luteolin. The DPPH assay was used in order to measure the antioxidant activity of the aqueous extract of B. trimera and this showed an IC50 of 118.18 ± 1.02 μg/mg. The data from the formalin test demonstrated that a single dose of the aqueous extract of B. trimera was not able to decrease the nociceptive behavior during the neurogenic phase, at any of the tested doses (20, 40, or 80 mg/kg p.o.). However, during the inflammatory phase of this test, the aqueous extract of B. trimera at 80 mg/kg (p.o.) significantly decreased the nociceptive behavior, showing more effectiveness when compared to the other tested doses (p < 0.05). Importantly, in the chronic inflammatory model on the 5th day of treatment, the aqueous extract of B. trimera (80 mg/kg p.o.) significantly reduced mechanical allodynia (p < 0.01), heat thermal hyperalgesia (p < 0.001), and paw edema (p < 0.05). There were no changes in the MPO activity, but the data exhibited an equivalent decrease in the number of lymphocytes in the blood of the mice that were treated with B. trimera (80 mg.kg− 1 p.o.) and diclofenac sodium.

Conclusion

Taken together, the present data reinforces the potential of the B. trimera aqueous extract as an anti-inflammatory and analgesic compound.

Myrciaria dubia Juice (camu-camu) Exhibits Analgesic and Antiedematogenic Activities in Mice

The Myrciaria dubia (Myrtaceae) fruit is traditionally used to treat malnutrition due to its high levels of vitamin C and phenolic compounds. Because of its composition, this plant is very promising in the research of novel natural treatment for pain disorders. This study analyzed the phytochemical profile of M. dubia juice and assessed its antinociceptive and antiedematogenic potential. The phytochemical profile was determined through high-performance liquid chromatography (HPLC), the oral antinociceptive effect of M. dubia 50% juice (Md50) was evaluated by formalin, hot plate and Complete Freund's Adjuvant tests and the antiedematogenic activity by paw edema. HPLC revealed the presence of ascorbic acid, rutin, and ellagic acid as major compounds. Md50 showed an antinociceptive effect in the acute and chronic phases of the formalin test. In the hot plate test, Md50 also induced an antinociceptive effect of 0.5 up to 6 h, showing antinociceptive and antiedematogenic potential without changing the spontaneous locomotion of animals. All protocols were submitted and approved by the Ethics Committee for use of Animals of the Lutheran University of Brazil (protocol No. 2013-30P).

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.

In vivo and in vitro toxicological evaluations of aqueous extract from Cecropia pachystachya leaves

leaves are popularly used to treat asthma and diabetes. Despite the widespread consumption of this plant, there are few scientific studies regarding its toxicological potential. In order to conduct a thorough study concerning the potential adverse effects, the aim of this study was to assess acute and subacute toxicity tests of crude aqueous extract from C. pachystachya leaves (CAE-Cp) using in vivomodel, as well as in vitro cytotoxicity, genotoxicity and antioxidant activity. In addition, genotoxicity, and cytotoxicity of chlorogenic acid (CGA) and cytotoxicity of isoorientin (ISOO) were also evaluated. The antioxidant activity was verified by DPPH, cytotoxicity using sulforhodamine B (SRB) assay and genotoxicity by comet assay on V79 cells. The phytochemical analysis of CAE-Cp detected flavonoids and tannins, CGA and ISOO as the major compounds utilizing HPLC. The total flavonoid content (6.52 mg/g EQ) and antioxidant activity (EC₅₀ = 62.15 µg/ml) of CAE-Cp were determined. In vitro evaluations with CAE-Cp showed genotoxic effects at 0.31 to 2.5 mg/ml and an expressive cytotoxicity on HT-29 (IC₅₀ = 4.43 µg/ml) cells. CGA was genotoxic against V79 cells at 0.07 mg/ml and cytotoxic against to HT-29 (IC₅₀ = 71.70 µg/ml), OVCAR-3 (IC₅₀ = 80.07 µg/ml), MCF-7 (IC₅₀ = 45.58 µg/ml) and, NCI-H460 (IC₅₀ = 71.89 µg/ml) cancer cell lines. Wistar rats treated with a single dose (2,000 mg/kg) CAE-Cp decreased hemoglobin levels after 14 days, although no significant toxicity was observed in animals after 28 days. In view of the in vitro cytotoxicity and genotoxicity detected, further studies are necessary to establish the safe use of CAE-Cp.

Antigenotoxic and antimutagenic effects of Myrciaria dubia juice in mice submitted to ethanol 28-day treatment

Myrciaria dubia is a native plant from the Amazon region which produces red-purplish fruit rich in antioxidant compounds such as ascorbic acid, carotenoids, and phenolic. M. dubia fruit is used to prepare juices considered to possess high nutritional content providing health benefits. The aim of this study was to examine the ability of M. dubia juice to protect DNA against genomic instability induced by sub-acute ethanol consumption attributed to oxidative stress. Mice were treated for 28 days with juice at 25% and 50% diluted in distilled water or with the diluted combination juice plus ethanol (5 g/kg). The genotoxic/antigenotoxic and mutagenic/antimutagenic effects were assessed using comet assay in blood, liver, and kidney and micronucleus (MN) test with bone marrow. In addition, the mutagenicity was also evaluated using Salmonella/microsome assay. Phytochemical compounds were determined using HPLC/PDA/MS/MS. The juice did not induce genotoxic effects in blood, kidney, and liver cells at both doses. In combination with ethanol, the juice reduced the alcohol-mediated DNA damage in all tissues analyzed. Further, the juice did not produce mutagenic effects and decreased mutagenicity induced by ethanol in the bone marrow. The anthocyanins were major compounds detected by HPLC/PDA/MS/MS, which modulated genotoxic and mutagenic effects initiated by ethanol and at least in part appeared responsible for the observed antigenotoxic and antimutagenic effects of M. dubia juice.

Toxicological aspects of Campomanesia xanthocarpa Berg. associated with its phytochemical profile

Campomanesia xanthocarpa leaves are used as tea to treat diarrhea, inflammation, and hypercholesterolemia. Some pharmacological studies noted its beneficial uses of C. xanthocarpa; however, few investigations examined the toxicological profile of this plant. The aim of this study was to determine the chemical composition, genotoxic, and mutagenic potential of an aqueous extract of C. xanthocarpa leaves (CxAE), and potential protective effects against oxidative damage. Phytochemical constituents were determined using HPLC, and antioxidant effect in vitro was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Genotoxic effects and chromosomic mutations were assessed using comet assay and micronucleus (MN) test in Wistar rats treated with CxAE at 250, 500 or 1000 mg/kg for 7 consecutive days. Lipid peroxidation and antioxidant enzyme activities were measured in several tissues. CxAE induced mutations in TA98, TA97a, and TA102 strains. However, in the presence of metabolic activation, data were negative for all strains tested. Lack of mutagenicity was also observed in the MN test. This extract did not induce DNA damage, except when the highest concentration was used. DNA oxidative damage induced by hydrogen peroxide (H₂O₂) decreased in blood after treatment with CxAE. Lipid peroxidation levels were reduced while superoxide dismutase (SOD) activity increased in kidneys. The inhibitory concentration of CxAE required to lower DPPH levels to 50% was 38.47 ± 2.06 μg/ml. In conclusion, frameshift and oxidative mutations were observed only in the absence of metabolic activation which may be attributed to the presence of flavonoids such as quercetin. It is of interest that CxAE also showed protective effects against DNA oxidative damage associated with presence of ellagic acid, a phenolic acid with antioxidant activities. CxAE did not induce in vivo mutagenicity, suggesting that this extract poses a low toxic hazard over the short term.

Nutritional composition of Eragrostis teff and its association with the observed antimutagenic effects

Eragrostis teff is an Ethiopian native grass plant (Poaceae or Gramineae family) whose importance as a crop grain has increased in recent years. The aim of this study is to analyze the nutritional composition of its seeds and the mutagenic/antimutagenic activity of the hydroalcoholic extract of the seed flour. Chemical elements (colloquially known as minerals) were determined using Particle-Induced X-ray Emission (PIXE) and Flame Atomic Absorption Spectroscopy (FAAS), while the content of amino acids (aminogram) and fatty acids (profile of fatty acids) were quantified by HPLC. Mutagenic activities were tested using Salmonella/microsome assay. Mutagens doxorubicin, 4-nitroquinolin N-oxide, methylmethanosulphonate, and aflatoxin B-1 were used in Salmonella typhimurium TA98 and TA100 strains to assess antimutagenic activities. The major elements observed were K, P, S, Mg, and Ca. Almost all essential amino acids were observed and the predominance of unsaturated fatty acids in the total oil content of 2.72% (w/w) is also noted, including the two essential fatty acids alpha-linolenic acid (an omega-3 fatty acid) and linoleic acid (an omega-6 fatty acid). Hydroalcoholic extract of E. teff seed flour showed antimutagenic activity, protecting against frameshift and base pair substitution mutations. These findings provide valuable information for further development of healthier foods that can be produced with increasing yields and minimal environmental impact.

Eragrostis teff is an Ethiopian native grass plant (Poaceae or Gramineae family) whose importance as a crop grain has increased in recent years.

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.

Protective effects of acerola juice on genotoxicity induced by iron in vivo

Metal ions such as iron can induce DNA damage by inducing reactive oxygen species (ROS) and oxidative stress. Vitamin C is one of the most widely consumed antioxidants worldwide, present in many fruits and vegetables, especially inMalpighia glabra L., popularly known as acerola, native to Brazil. Acerola is considered a functional fruit due to its high antioxidant properties and phenolic contents, and therefore is consumed to prevent diseases or as adjuvant in treatment strategies. Here, the influence of ripe and unripe acerola juices on iron genotoxicity was analyzed in vivo using the comet assay and micronucleus test. The comet assay results showed that acerola juice exerted no genotoxic or antigenotoxic activity. Neither ripe nor unripe acerola juices were mutagenic to animals treated with juices, in micronucleus test. However, when compared to iron group, the pre-treatment with acerola juices exerted antimutagenic activity, decreasing significantly micronucleus mean values in bone marrow. Stage of ripeness did not influence the interaction of acerola compounds with DNA, and both ripe and unripe acerola juices exerted protective effect over DNA damage generated by iron.

Evaluation of Safety of Arrabidaea chica Verlot (Bignoniaceae), a Plant with Healing Properties

Arrabidaea chica Verlot (Bignoniaceae) has been used as a medicinal herb to treat anemia, hemorrhage, inflammation, intestinal colic, hepatitis, and skin infections in the Brazilian Amazon region. Studies have demonstrated the healing properties of extracts obtained from A. chica leaves, which contain anthocyanins and flavonoids. However, few investigations have assessed the safe use of this plant species. In this study, mutagenic and genotoxic effects of a crude aqueous extract, a butanolic fraction, and aqueous waste from A. chica leaves were evaluated using the Salmonella/microsome assay in TA98, TA97a, TA100, TA102, and TA1535 strains and the alkaline comet assay in Chinese hamster ovary (CHO) cell culture with and without metabolic activation. The crude aqueous extract, butanolic fraction, and aqueous waste were not mutagenic in any of the Salmonella typhimurium strains tested, and showed negative responses for genotoxicity in CHO cells. High-performance liquid chromatography (HPLC) analysis indicated the presence of phenolic acids and flavonoids such as rutin and luteolin. The lack of mutagenic/genotoxic effects might be due to phytochemical composition with high concentrations of known anti-inflammatory compounds. Thus, the crude aqueous extract, butanolic fraction, and aqueous waste from A. chica leaves do not appear to pose short-term genotoxic risks.

Corrective effects of acerola (Malpighia emarginata DC.) juice intake on biochemical and genotoxical parameters in mice fed on a high-fat diet

Acerola contains high levels of vitamin C and rutin and shows the corresponding antioxidant properties. Oxidative stress on the other hand is an important factor in the development of obesity. In this study, we investigated the biochemical and antigenotoxic effects of acerola juice in different stages of maturity (unripe, ripe and industrial) and its main pharmacologically active components vitamin C and rutin, when given as food supplements to obese mice. Initial HPLC analyses confirmed that all types of acerola juice contained high levels of vitamin C and rutin. DPPH tests quantified the antioxidant properties of these juices and revealed higher antioxidant potentials compared to pure vitamin C and rutin. In an animal test series, groups of male mice were fed on a standard (STA) or a cafeteria (CAF) diet for 13 weeks. The latter consisted of a variety of supermarket products, rich in sugar and fat. This CAF diet increased the feed efficiency, but also induced glucose intolerance and DNA damage, which was established by comet assays and micronucleus tests. Subsequently, CAF mice were given additional diet supplements (acerola juice, vitamin C or rutin) for one month and the effects on bone marrow, peripheral blood, liver, kidney, and brain were examined. The results indicated that food supplementation with ripe or industrial acerola juice led to a partial reversal of the diet-induced DNA damage in the blood, kidney, liver and bone marrow. For unripe acerola juice food supplementation, beneficial effects were observed in blood, kidney and bone marrow. Food supplementation with vitamin C led to decreased DNA damage in kidney and liver, whereas rutin supplementation led to decreased DNA damage in all tissue samples observed. These results suggest that acerola juice helps to reduce oxidative stress and may decrease genotoxicity under obesogenic conditions.

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.

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.

Protective activity of Cynara scolymus L. leaf extract against chemically induced complex genomic alterations in CHO cells

Cynara scolymus L., popularly known as artichoke, has been widely used in traditional medicine as an herbal medicament for therapeutic purposes. The study aimed at assessing the protective activity of Cynara scolymus leaf extract (LE) against DNA lesions induced by the alkylating agent ethylmethnesulphonate (EMS) in Chinese hamster ovary cells (CHO). The ability of C. scolymus L. LE to modulate the mutagenicity of EMS was examined using the cytokinesis block micronucleus (CBMN) cytome assay in three antigenotoxic protocols, pre- post- and simultaneous treatments. In the pre-treatment, C. scolymus L. LE reduced the frequencies of MNi and NBUDs induced by EMS in the lower concentration. In contrast, at the highest concentration (5 mg/ml) artichoke enhanced the frequency of MNi, potentiating EMS genotoxicity. In the simultaneous treatment only the induction of MNi was repressed by the exposure of cells to C. scolymus L. LE. No modification in genotoxicity was observed in LE post-treatment. The results obtained in this study suggest that lower concentrations of artichoke prevent chemically induced genomic damage in mammalian cells. In this context, the protective activity of C. scolymus L. could be associated to its constitutive antioxidants compounds.

Evaluation of the mutagenicity and genotoxicity of Arrabidaea chica Verlot (Bignoneaceae), an Amazon plant with medicinal properties

Arrabidaea chica Verlot (Bignoniaceae) is an important folk medicine plant native to the Amazon region and used to treat anemia, hemorrhage, inflammation, intestinal colic, hepatitis, and skin affections. Although studies showed its therapeutic properties, little knowledge regarding genotoxic properties of this plant is available. The aim of this study was to determine the potential mutagenic and genotoxic/antigenotoxic effects of an A. chica chloroformic fraction (Ac-CF) obtained from leaves containing bioactive metabolites. The mutagenic effects were evaluated using the Salmonella mutagenicity assay, with TA98, TA97a, TA100, TA102, and TA1535 strains, with and without metabolic activation. In vivo mutagenic and genotoxic/antigenotoxic effects were investigated using the micronucleus (MN) test in bone marrow and alkaline comet assay in blood and liver after administration of 100, 500, or 1000 mg/kg Ac-CF in CF-1 mice by gavage (once a day for 3 d). In vitro antioxidant potential was evaluated using DPPH and xanthine/hypoxanthine assays. Ac-CF was not mutagenic in any of the Salmonella typhimurium strains tested and showed negative responses for mutagenicity and genotoxicity in mice. Further, Ac-CF displayed antigenotoxic effects by decreasing the oxidative DNA damage induced by hydrogen peroxide by greater than 50% in blood and liver. The antioxidant action detected in the in vitro assays demonstrated IC50 of 0.838 mg/ml in the xanthine/hypoxanthine assay and IC50 of 28.17 μg/ml in the DPPH assay. In conclusion, Ac-CF did not induce mutagenic and genotoxic effects and was able to protect DNA against oxidative damage in vivo, suggesting that this fraction may not pose genetic risks, although further toxicology assays are necessary.

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.

Antigenotoxicity and antioxidant activity of Acerola fruit (Malpighia glabra L.) at two stages of ripeness

Genotoxic and antigenotoxic effects of acerola fruit at two stages of ripeness were investigated using mice blood cells. The results show that no ripeness stage of acerola extracts presented any genotoxic potential to damage DNA (Comet assay) or cytotoxicity (MTT assay). When antigenotoxic activity was analyzed, unripe fruit presented higher DNA protection than ripe fruit (red color) extract. The antioxidant capacity of substances also showed that unripe samples inhibit the free radical DPPH more significantly than the ripe ones. The results about determination of compounds made using HPLC showed that unripe acerola presents higher levels of vitamin C as compared to ripe acerola. Thus, vitamin C and the complex mixture of nutrients of Malpighia glabra L., and especially its ripeness stages, influenced the interaction of the fruit extract with the DNA. Acerola is usually consumed when ripe (red fruit), although it is the green fruit (unripe) that has higher potential as beneficial to DNA, protecting it against oxidative stress.

Toxicological evaluation of Pterocaulon polystachyum extract: a medicinal plant with antifungal activity

Pterocaulon polystachyum DC is a native species to southern Brazil, Paraguay, Uruguay and northeastern Argentina. It is utilized to treat animal problems popularly diagnosed as "mycoses". The antifungal and amebicidal activity of its hexane extract has been previously reported, although there are no studies confirming the safety of this plant for therapeutic purposes to date. Hence, this study investigates the toxic effects of a hexane extract of Pterocaulon polystachyum administered as acute and subacute oral treatments. After acute treatment the extract caused alterations in biochemical parameters, morphological alterations in tissues and was genotoxic, according to the comet assay; neither mortality nor visible signs of lethality were seen in mice. Similarly subacute treatment caused important differences in biochemical parameters and tissues, between control and treated groups. The results also revealed genotoxicity in kidney tissue, though no mutagenicity was detected by the micronucleus test. No animal died during the treatment period.

Neurobehavioral and toxicological activities of two potentially CNS-acting medicinal plants of Piper genus

Plants from the genus Piper are economically useful and some species have been indicated because of their medicinal properties in the central nervous system. However, few studies about toxicity and neurobehavioral effects have been conducted. In this study, two Piper species, P. amalago and P. mikanianum were investigated in rats to determine acute toxicity and to evaluate the ansiogenic/ansiolytic properties in the elevated plus-maze and the effects on locomotion and exploration in an open field. Additionally, genotoxic activities were evaluated, using the comet assay in several tissues and the micronucleus assay in bone marrow. The phytochemical analysis of both Piper species leaves suggests the presence of amide, essential oils, flavonoids and phenolic compounds. The LD(50) of P. amalago and P. mikanianum were estimated as 2,545 and 1,661 mg/kg, respectively. The behavioral and genotoxic parameters were determined after an intraperitoneal administration of P. amalago (250 or 420 mg/kg) or P. mikanianum (160 or 270 mg/kg). Both plants decreased the number of entries and time spent in the open arms in the plus-maze test, indicating an anxiogenic effect. Only P. mikanianum affected locomotion and exploration in the open field behavior test. No genotoxic or mutagenic effect was observed. Our results suggest that these Piper species act on the central nervous system, without induce genetic toxicity.

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.