Cytogenotoxic evaluations of leaves and stems extracts of Rubus rosifolius in primary metabolically noncompetent cells.

Plants with medicinal potential may also produce adverse effects in humans. This seems to be the case for the species Rubus rosifolius, where preliminary studies demonstrated genotoxic effects attributed to extracts obtained from leaves and stems of this plant using on HepG2/C3A human hepatoma cells as a model. Considering the beneficial properties of this plant as an antidiarrheal, analgesic, antimicrobial, and antihypertensive and its effects in the treatment of gastrointestinal diseases, the present study was developed with the aim of determining the cytotoxic and genotoxic potential of extracts of leaves and stems of R. rosifolius in primary without metabolic competence in human peripheral blood mononuclear cells (PBMC). Cell viability analyses at concentrations of between 0.01 and 100 µg/ml of both extracts did not markedly affect cell viability. In contrast, assessment of the genotoxic potential using the comet assay demonstrated significant damage to DNA within PBMC from a concentration of 10 µg/ml in the stem extract, and a clastogenic/aneugenic response without cytokinesis-block proliferation index (CBPI) alterations at concentrations of 10, 20, or 100 µg/ml for both extracts. Under our experimental conditions, the data obtained demonstrated genotoxic and mutagenic effects attributed to extracts from leaves and stems of R. rosifolius in cells in the absence of hepatic metabolism.

Rubus rosifolius (Rosaceae) stem extract induces cell injury and apoptosis in human hepatoma cell line.

Rubus rosifolius, popularly known as "red mulberry", is a common medicinal plant in southern Brazil and is used as an antidiarrheal, analgesic, antimicrobial and antihypertensive, and to treat stomach diseases. The aim of this study was to analyze the R. rosifolius stem extract (RrSE) for possible in vitro cytotoxic and genotoxic effects, using the comet assay and the micronucleus test to assess genotoxicity, and flow cytometry to assess the impact on the cell cycle and apoptosis in HepG2/C3A cells, in addition to evaluating the expression of genes linked to the induction of DNA damage, cell cycle, apoptosis and metabolism of xenobiotics. The MTT assay observed no cytotoxic effects at concentrations between 0.01 and 100 µg/mL of the extract. However, genotoxic effects occurred in treatments with the extract from a 1 µg/mL concentration. Flow cytometry analysis revealed a significant increase in cells in the G2/M phase after treatment with 10 µg/mL, a decrease in cells in the G0/G1 phase in the treatment with 100 µg/mL, and a significant increase in total apoptotic cells. In the gene expression analysis, an increase in the CYP1A2 xenobiotics metabolizing gene expression was observed. Despite the promising pharmacological effects of R. rosifolius, the results revealed that the RrSE has genotoxic effect and induces apoptosis in HepG2/C3A cells, indicating danger in using this plant extract by humans.

In vivo toxicogenic potential of Salix alba (Salicaceae) bark extract.

Salix alba (white willow) bark extract is widely used for conditions associated with inflammation, fever, microbial infection or pain. Exposure of human cultured leukocytes to S. alba in vitro noted a genotoxic response. However, data regarding the influence of this bark extract on DNA damage in vivo are lacking. The main goal of this study was to examine the potential of S.alba bark extract to induce DNA damage and chromosome aberrations in an in vivo model using cells obtained from male Swiss albino mice administered the compound orally. The extract was administered by oral gavage daily for 7 days at doses of 500, 1000, or 2000 mg/kg b.w. Genotoxicity analysis was performed using the comet assay on peripheral blood leukocytes, as well as liver, bone marrow, heart, and testicular cells collected 4 hr after the last treatment and the micronucleus (MN) test on bone marrow cells. In essence cells were collected 28 hr after the penultimate treatment Data demonstrated that S. alba bark extract did not induce significant DNA damage in any cell types examined, or clastogenic/aneugenic effects as detected by the MN test at the three tested doses. Under these experimental conditions, evidence indicates that S.alba bark extract did not initiate genotoxic or chromosome aberrations in various mouse cells investigated.

Risk assessment via genotoxicity, metabolism, apoptosis, and cell growth effects in a HepG2/C3A cell line upon treatment with Rubus rosifolius (Rosaceae) leaves extract.

RUBUS ROSIFOLIUS: Sm. (Rosaceae) is a plant traditionally used in Brazil and some other countries to treat diarrhea, stomach diseases, and as an analgesic, antimicrobial, antihypertensive, and as well as other pharmacological properties. The aim of this study was to examine cytotoxic and genotoxic effects of R. rosifolius leaves extract on HepG2/C3A cells and correlate these findings with the expression of mRNA to underlying mechanisms of action. At concentrations between 0.01 and 100 µg/ml, cytotoxic effects were not detected by the MTT assay. This was confirmed by mRNA induction of the CYP3A4 gene (by RT-qPCR assay). However, genotoxic effects occurred at treatments from 1 µg/ml extract (comet and micronucleus test). An increase in the number of cells in S phase was observed at 100 µg/ml, and an elevation in apoptotic cell number was found for all tested concentrations (10, 20, or 100 µg/ml) (cell cycle and apoptosis analysis by flow cytometry). The genotoxicity induced by the extract was the main cause of the rise in the number of cells undergoing apoptosis, as indicated by rise in mRNA of CASP7 gene, and elevation of cells in the S phase of the cell cycle at the higher tested concentrations, as an attempt to repair genetic damage that occurred. These observations suggest that, despite its pharmacological potential, the use of R. rosifolius leaves extract may pose a risk to the integrity of the genetic material of human cells.

Salix alba (white willow) medicinal plant presents genotoxic effects in human cultured leukocytes.

Salix alba (SA), commonly known as white willow, is a plant used in folk medicine for the treatment of chronic and acute inflammation, infection, pain, and fever. The phytochemical characterization of the bark extract of this plant indicated that its main component is salicin, a precursor of the anti-inflammatory agent acetylsalicylic acid. Considering the lack of studies evaluating the genetic toxicity and cytotoxic action of SA bark extract on human cells, as well as the chemical characterization of its major phenolic compounds, the present study was designed to (1) investigate the cytotoxic and genotoxic potential of SA bark extract on human peripheral leukocyte cells and human hepatoma cell line HepG2, and (2) characterize its major phenolic constituents. The phenolic compounds found were salicylic acid, salicin, salidroside, saligenin, tremulodin, salicoylsalicin, salicortin, and tremulacin. The results using trypan blue staining test showed viability decreases (viability less than 70%) for concentrations of SA extract equal and higher to 200 µg/ml. Low genotoxic activity (comet assay) was exhibited for 50 and 100 µg/ml SA extract in human leukocytes. SA did not exert a marked clastogenic/aneugenic effect on leukocytes and HepG2 human cells. Data suggest that the genotoxic effects of SA bark extract occur when it is not metabolized by liver enzymes.

The genotoxic effects of fruit extract of Crataegus oxyacantha (hawthorn) in mice.

Crataegus oxyacantha L. (Rosaceae) is a medicinal plant with a long history of use in European, Chinese, and American. The majority of pharmacological activities associated with fruit extracts of C. oxyacantha L. are related to cardio-stimulant properties utilized in the treatment of atherosclerosis, hypertension with myocardic insufficiency, angina pectoris, cardiac rhythm alterations, and heart failure. Some other therapeutic uses for renal calculi, dyspnea, as well as a diuretic, sedative, and anxiolytic were also reported. Due to the beneficial potential of C. oxyacantha fruits extract but evidence in vitro of genetic toxicity, the aim of the present study was to examine the genotoxic potential of plant extract in vivo in mice. The extract was administered orally, daily by gavage at doses of 50, 100, and 200 mg/kg body weight for seven days. Data demonstrated that C. oxyacantha extract did not markedly induce DNA damage in leukocytes and bone marrow cells by the comet assay; however, the extract produced a significant rise in micronucleated polychromatic erythrocytes (PCE) at all tested doses in a non-dose dependent manner as evidenced by the micronucleus test. The PCE/normochromatic erythrocytes (NCE) ratio indicated no significant cytotoxicity. Under our experimental conditions, C. oxyacantha fruits extract exhibited weak clastogenic and/or aneugenic effects in bone marrow cells of male mice, confirming our previous in vitro findings that this plant extract induced genotoxicity suggesting that prolonged or high dose use needs to be undertaken with caution.

Fruit extract of the medicinal plant Crataegus oxyacantha exerts genotoxic and mutagenic effects in cultured cells.

Crataegus oxyacantha, a plant of the Rosaceae family also known "English hawthorn, haw, maybush, or whitethorn," has long been used for medicinal purposes such as digestive disorders, hyperlipidemia, dyspnea, inducing diuresis, and preventing kidney stones. However, the predominant use of this plant has been to treat cardiovascular disorders. Due to a lack of studies on the genotoxicity of C. oxyacantha, this investigation was undertaken to determine whether its fruit extract exerts cytotoxic, genotoxic, or clastogenic/aneugenic effects in leukocytes and HepG2 (liver hepatocellular carcinoma) cultured human cells, or mutagenic effects in TA100 and TA98 strains of Salmonella typhimurium bacterium. Genotoxicity analysis showed that the extract produced no marked genotoxic effects at concentrations of 2.5 or 5 µg/ml in either cell type; however, at concentrations of 10 µg/ml or higher significant DNA damage was detected. The micronucleus test also demonstrated that concentrations of 10 µg/ml or higher produced clastogenic/aneugenic responses. In the Ames test, the extract induced mutagenic effects in TA98 strain of S. typhimurium with metabolic activation at all tested concentrations (2.5 to 500 µg/ml). Data indicate that, under certain experimental conditions, the fruit extract of C. oxyacantha exerts genotoxic and clastogenic/aneugenic effects in cultured human cells, and with metabolism mutagenicity occurs in bacteria cells.

In vivo evaluation of the genetic toxicity of Rubus niveus Thunb. (Rosaceae) extract and initial screening of its potential chemoprevention against doxorubicin-induced DNA damage.

ETHNOPHARMACOLOGICAL RELEVANCE: Rubus niveus Thunb. plant belongs to Rosaceae family and have been used traditionally to treat wounds, burns, inflammation, dysentery, diarrhea and for curing excessive bleeding during menstrual cycle. The present study was undertaken to investigate the in vivo genotoxicity of Rubus niveus aerial parts extract and its possible chemoprotection on doxorubicin (DXR)-induced DNA damage. In parallel, the main phytochemicals constituents in the extract were determined. MATERIALS AND METHODS: The animals were exposed to the extract for 24 and 48 h, and the doses selected were 500, 1000 and 2000 mg/kg b.w. administered by gavage alone or prior to DXR (30 mg/kg b.w.) administered by intraperitoneal injection. The endpoints analyzed were DNA damage in bone marrow and peripheral blood cells assessed by the alkaline alkaline (pH>13) comet assay and bone marrow micronucleus test. RESULTS AND CONCLUSION: The results of chemical analysis of the extract showed the presence of tormentic acid, stigmasterol, quercitinglucoronide (miquelianin) and niga-ichigoside F1 as main compounds. Both cytogenetic endpoints analyzed showed that there were no statistically significant differences (p>0.05) between the negative control and the treated groups with the two higher doses of Rubus niveus extract alone, demonstrating absence of genotoxic and mutagenic effects. Aneugenic/clastogenic effect was observed only at 2000 mg/kg dose. On the other hand, in the both assays and all tested doses were observed a significant reduction of DNA damage and chromosomal aberrations in all groups co-treated with DXR and extract compared to those which received only DXR. These results indicate that Rubus niveus aerial parts extract did not revealed any genotoxic effect, but presented some aneugenic/clastogenic effect at higher dose; and suggest that it could be a potential adjuvant against development of second malignant neoplasms caused by the cancer chemotherapic DXR.

Reproductive toxicology and clastogenic evaluation in mice of a phytotherapeutic formulation obtained from Cinchona calisaya Weddel (Rubiaceae) used in Brazilian folk medicine as female fertility stimulant.

ETHNOPHARMACOLOGICAL RELEVANCE: In Brazil, a phytotherapeutic preparation produced from a standardized tincture of Cinchona calisaya Weddel such that each mL of product contains 400µg of quinine, known in Portuguese as Água Inglesa(®) (English water), is indicated by the manufacturer as a tonic, appetite stimulant, and digestive. However, this preparation has long been used in folk medicine as a female fertility stimulant. Despite its widespread use in folk medicine to stimulate female fertility, no study has been undertaken to assess the potential teratogenic and genotoxic effects of this phytotherapeutic preparation. The aim of the present study was to investigate possible toxic reproductive effects in mice caused by exposure to Água Inglesa(®), either before mating or during the pre- and post-embryo implantation periods. The genotoxic potential was evaluated using the micronucleus assay. MATERIAL, METHODS, AND RESULTS: Virgin female mice, with at least one estrous cycle evidenced by vaginal cytology, were divided into five groups of 15 individuals each (Group I - control, Group II - treated with ethanol solution at 16%, Groups III, IV and V treated with phytotherapeutic preparation at 1.5mL/kg/day, 3.0mL/kg/day and 4.5mL/kg/day, respectively). After the first 28 days of treatment, females were caged individually with adult fertile males. Pregnant females continued to receive treatment for seven days (preimplantation period). Body weight was recorded weekly during treatment. Signs of toxicity (weight loss, food intake, piloerection, apathy, prostration, diarrhea, seizures, behavioral changes, and locomotion) were also observed. The females were sacrificed on the 15th day of pregnancy, uterine horns were evaluated for implantation, and the placental index was recorded. In the micronucleus test, 2000 polychromatic erythrocytes (PCE) per animal, obtained from bone marrow, were scored. Results The results showed that exposure of the females during the pre- and post-implantation periods did not significantly alter the reproductive capacity (p<0.05); however, in higher dose (three times human dose)reduction of fetal weight was observed . There was no difference between the control and phytotherapeutic preparation (p>0.05) in terms of the average number of micronucleated polychromatic erythrocytes. CONCLUSIONS: Although folk medicine suggests that the Água Inglesa(®) preparation is useful as a female fertility stimulant, no such effect was confirmed in mice.

Genotoxic assessment of Rubus imperialis (Rosaceae) extract in vivo and its potential chemoprevention against cyclophosphamide-induced DNA damage.

ETHNOPHARMACOLOGICAL RELEVANCE: Rubus imperialis Cham. Schl. (Rosaceae) is frequently used in traditional medicine as hypoglycemic, antinociceptive and antiviral remedy. MATERIALS AND METHODS: Swiss albino mice were distributed in eight groups for acute treatment with Rubus imperialis extract (24 h). The extract doses selected were 50, 250 and 500 mg/kg b.w. administered by gavage alone or plus to CPA (50 mg/kg b.w.) administered by intraperitoneal injection. Control groups were treated in a similar way. Analyses were performed using the comet assay, on leukocytes (collected 4 and 24h after treatment) and liver (collected 24 h after treatment), and using the micronucleus test (MN) in bone marrow cells. Cytotoxicity was assessed by scoring 200 consecutive polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE/NCE ratio). RESULTS AND CONCLUSION: The main compounds identified in the Rubus imperialis extract were saponins and steroidal compounds, with niga-ichigoside and tormentic acid being the major compounds. Tested doses of Rubus imperialis extract showed no genotoxic effects on leukocytes from peripheral blood or liver cells by the comet assay. However, the MN test showed an increase in the frequency of micronucleated cells at the two higher doses tested, indicating that this extract has clastogenic/aneugenic effects on bone marrow cells at higher doses. On the other hand, for all cells evaluated, the three tested doses of the Rubus imperialis extract promoted inhibition of DNA damage induced by CPA. Despite the chemoprevention observed, the clastogenicity/aneugenicity observed suggested caution about either continuous or high-dose usage of Rubus imperialis aerial parts extract by humans.

Absence of genotoxic effects of the coumarin derivative 4-methylesculetin in vivo and its potential chemoprevention against doxorubicin-induced DNA damage.

4-Methylesculetin (4-ME) is a synthetic derivative of coumarin that displays a potent reactive oxygen species (ROS) scavenger and metal chelating agent and therefore has been produced to help reduce the risk of human disease. The main objective of this study was to investigate the in vivo genotoxicity of 4-ME and initially to verify its potential antigenotoxicity on doxorubicin (DXR)-induced DNA damage. Different doses of 4-ME (500, 1000 and 2000 mg kg(-1) body weight) were administered by gavage only or with a simultaneous intraperitoneal (i.p.) injection of DXR (80 mg kg(-1)). The following endpoints were analyzed: DNA damage in peripheral blood, liver, bone marrow, brain and testicle cells according to an alkaline (pH > 13) comet assay and micronucleus induction in bone marrow cells. Cytotoxicity was assessed by scoring polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE/NCE ratio). No differences were observed between the negative control and the groups treated with a 4-ME dose for any of the endpoints analyzed, indicating that it lacks genotoxic and cytotoxic effects. Moreover, 4-ME demonstrated protective effects against DXR-induced DNA damage at all tested doses and in all analyzed cell types, which ranged from 34.1% to 93.3% in the comet assay and 54.4% to 65.9% in the micronucleus test.

Benzophenone guttiferone A from Garcinia achachairu Rusby (Clusiaceae) presents genotoxic effects in different cells of mice.

Benzophenones from natural sources and those of synthetic analogues present several reports of potent biological properties, and Guttiferone A represents a promising medicinal natural compound with analgesic and gastroprotective profiles. Considering that there are no reports that assess the genetic toxicity of Guttiferone A, the present study was undertaken to investigate the genotoxic potential of this benzophenone isolated from seeds of Garcinia achachairu in terms of DNA damage in different cells of Swiss albino mice using the comet assay, and its clastogenic/aneugenic effects in bone marrow cells in vivo by the micronucleus test. Cytotoxicity was assessed by scoring polychromatic (PCE) and normochromatic (NCE) erythrocytes ratio. Guttiferone A was administered by oral gavage at doses of 15, 30 and 60 mg/kg. The results showed that Guttiferone A produced genotoxic effects in leukocytes, liver, bone marrow, brain and testicle cells and clastogenic/aneugenic effects in bone marrow erythrocytes of mice. The PCE/NCE ratio indicated no cytotoxicity. Since guttiferone A is harmful to the genetic material we suggest caution in its use by humans.

Dragon's blood Croton palanostigma induces genotoxic effects in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Dragon's blood is a dark-red sap produced by species from the genus Croton (Euphorbiaceae), which has been used as a famous traditional medicine since ancient times in many countries, with scarce data about its safe use in humans. In this research, we studied genotoxicity and clastogenicity of Croton palanostigma sap using the comet assay and micronucleus test in cells of mice submitted to acute treatment. MATERIAL AND METHODS: HPLC analysis was performed to identify the main components of the sap. The sap was administered by oral gavage at doses of 300 mg/kg, 1,000 mg/kg and 2,000 mg/kg. For the analysis, the comet assay was performed on the leukocytes and liver cells collected 24h after treatment, and the micronucleus test (MN) on bone marrow cells. Cytotoxicity was assessed by scoring 200 consecutive polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE/NCE ratio). RESULTS AND CONCLUSION: The alkaloid taspine was the main compound indentified in the crude sap of Croton palanostigma. The results of the genotoxicity assessment show that all sap doses tested produced genotoxic effects in leukocytes and liver cells and also produced clastogenic/aneugenic effects in bone marrow cells of mice at the two higher doses tested. The PCE/NCE ratio indicated no cytotoxicity. The data obtained suggest caution in the use of Croton palanostigma sap by humans considering its risk of carcinogenesis.

Evaluation of the genotoxic and antigenotoxic potential of Brassica oleracea L. var. acephala D.C. in different cells of mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Brassica oleracea L. var. acephala D.C. has been extensively used in Brazilian traditional medicine to treat gastric ulcer. AIM OF THE STUDY: This study was conducted to evaluate the in vivo genotoxic and/or antigenotoxic potential of a Brassica oleraceae hydroalcoholic extract obtained from the leaves, in different cells of mice. MATERIALS AND METHODS: Analyses were performed using the comet assay, on leukocytes (collected 4 and 24 h after treatment), liver, brain, bone marrow and testicular cells (collected 24 h after treatment), and using the micronucleus test (MN) in bone marrow cells. Eight groups of albino Swiss mice were treated (N=6): control (C), positive control (doxorubicin 80 mg/kg (DXR)), and six experimental groups, which received 500, 1000 and 2000 mg/kg of Brassica oleraceae extract alone by gavage, while a further three groups received the same doses plus DXR (80 mg/kg). We calculated the damage scores, and their averages were compared by ANOVA followed by the Tukey test for multiple comparisons. RESULTS: The results demonstrated that none of the tested doses of Brassica oleraceae extract showed genotoxic effects by the comet assay, or clastogenic effects by the MN test. On the other hand, for all cells evaluated, the three tested doses of the Brassica extract promoted inhibition of DNA damage induced by DXR. CONCLUSIONS: Under our experimental conditions, Brassica oleraceae leaf extract showed no genotoxic or clastogenic effects in different cells of mice. However, it did show a significant decrease in DNA damage induced by doxorubicin. It is suggested that the antigenotoxic properties of this extract may be of great pharmacological importance, and may be beneficial for cancer prevention.

Genotoxicity assessment of Garcinia achachairu Rusby (Clusiaceae) extract in mammalian cells in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Garcinia achachairu Rusby (Clusiaceae) is popularly known as "achachairu", and is used in Bolivian folk medicine for its healing, digestive, and laxative properties, and in the treatment of gastritis, rheumatism and inflammation. Despite its widespread therapeutic use, there is a lack of data regarding its in vivo genotoxic effects. Therefore, in this study, we used the comet assay and the micronucleus test, respectively, to evaluate the possible genotoxic and clastogenic effects of Garcinia achachairu seed extract (GAE) on different cells of mice. MATERIAL AND METHODS: The GAE was administered by oral gavage at doses of 500, 1000 and 2000 mg/kg. For the analysis, the comet assay was performed on the leukocytes (collected 4 and 24 h after treatment), liver, bone marrow and testicular cells (collected 24 h after treatment), and the micronucleus test (MN) on bone marrow cells. Cytotoxicity was assessed by scoring 200 consecutive polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE/NCE ratio). RESULTS AND CONCLUSION: The results showed that GAE did not induce significant DNA damage in leukocytes (4 h and 24 h samples), liver, bone marrow and testicular cells (24 h samples). GAE also did not show any significant increase in micronucleated polychromatic erythrocytes (MNPCEs) at the three tested doses. The PCE/NCE ratio indicated no cytotoxicity. Under our experimental conditions, the data obtained suggest that a single oral administration of G. achachairu extract does not cause genotoxicity and clastogenicity in different cells of mice.

Nandrolone androgenic hormone presents genotoxic effects in different cells of mice.

Nandrolone is an androgenic-anabolic steroid (AAS) with diverse medical applications but taken indiscriminately by some to rapidly increase muscle mass. The aim of this study was to evaluate the genotoxic and clastogenic potential of nandrolone (deca-durabolin®) in vivo in different cells of mice, using the comet assay and micronucleus test, respectively. The animals received subcutaneous injection of the three doses of the steroid (1.0, 2.5 and 5.0 mg kg⁻¹ body weight). Cytotoxicity was assessed by scoring 200 consecutive total polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE-NCE ratio). The results showed a significant dose-related increase in the frequency of DNA damage in leukocytes, liver, bone marrow, brain and testicle cells at the three tested doses and a significant increase of the micronucleated polychromatic erythrocytes at all tested doses. Under our experimental conditions, the nandrolone steroid hormone showed genotoxic and clastogenic effects when administered subcutaneously to mice.

Lapachol induces clastogenic effects in rats.

Lapachol is a naturally occurring naphthoquinone derivative found in the heartwood of several plants, particularly those of the genus Tabebuia (Bignoneaceae). Despite its use as a therapeutic product with anti-inflammatory, analgesic, antipsoriatic, trypanocidal effects, among others, its in vivo mutagenic potential has still not been investigated. This paper reports the effects after a single oral administration of lapachol in the in vivo micronucleus (MN) and chromosome aberration (CA) assays. Both assays were performed using bone marrow cells from male Wistar rats. The animals were treated by oral gavage with hydroalcoholic solutions of lapachol at the doses of 122, 244 and 365 mg/kg, chosen on the basis of the LD(50) in male rats. The results show that the higher administered lapachol dose induced a significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCE) and CAs in rat bone marrow cells, indicating that lapachol shows clastogenic effects under the experimental conditions used.

Antiulcerogenic activity of the essential oil of Baccharis dracunculifolia on different experimental models in rats.

Baccharis dracunculifolia DC (Asteraceae), a native plant from Brazil, commonly known as 'Alecrimdo-campo' is widely used in folk medicine to treat inflammation, hepatic disorders and stomach ulcers, and it is the most important botanical source of Southeastern Brazilian propolis, known as green propolis. Its essential oil is composed of non-oxygenated and oxygenated terpenes. In this work, the effects of the essential oil obtained from the aerial parts of B. dracunculifolia on gastric ulcers were evaluated. The antiulcer assays were undertaken using the following protocols in rats: nonsteroidal antiinflammatory drug (NSAID)-induced ulcer, ethanol-induced ulcer, stress-induced ulcer, and determination of gastric secretion using ligated pylorus. The treatment in the doses of 50, 250 and 500 mg/kg of B. dracunculifolia essential oil significantly diminished the lesion index, the total lesion area and the percentage of lesions in comparison with both positive and negative control groups. With regard to the model of gastric secretion a reduction of gastric juice volume and total acidity was observed, as well as an increase in the gastric pH. No sign of toxicity was observed in the acute toxicity study. Considering the results, it is suggested that the essential oil of B. dracunculifolia could probably be a good therapeutic agent for the development of new phytotherapeutic medicine for the treatment of gastric ulcer.

Evaluation of antiulcer activity of the main phenolic acids found in Brazilian Green Propolis.

AIM OF THE STUDY: In a previous study, our group described the gastric protective effect of the hydroalcoholic extract of Brazilian green propolis. The main compounds found in Brazilian green propolis include phenolic acids, such as: caffeic, ferulic, p-coumaric and cinnamic acids. This study was therefore carried out to evaluate the antiulcerogenic property of the main phenolic acids found in Brazilian Green Propolis. MATERIAL AND METHODS: The anti-ulcer assays were performed using the following protocols: nonsteroidal-antiinflammatory drug (NSAID)-induced ulcer, ethanol-induced ulcer, and stress-induced ulcer. The effects of the phenolic acids on gastric content volume, pH and total acidity, using the pylorus ligated model, were also evaluated. RESULTS: It was observed that treatment using doses of 50 and 250 mg/kg of caffeic, ferulic, p-coumaric and cinnamic acids and positive controls (omeprazol or cimetidine) significantly diminished the lesion index, the total area of the lesion and the percentage of lesion in comparison with the negative control groups. In addition, the percentage of ulcer inhibition was significantly higher in the groups treated with the different phenolic acids, cimetidine or omeprazol, in all the protocols used, compared with the negative control groups. In the model to determine gastric secretion, using ligated pylorus, treatment with phenolic acids and cimetidine reduced the volume of gastric juice and total acidity and significantly increased the gastric pH (p<0.05), compared with the control group, with the exception of the group treated with 50mg/kg of p-coumaric acid, in which no significant difference was observed, compared with the control. In relation to the acute toxicity, none sign of toxicity was observed when phenolic acids, used in this study, were administered for rats in dose of 2,000 mg/kg. CONCLUSIONS: In conclusion, the results of this study show that caffeic, ferulic, p-coumaric and cinnamic acids display antiulcer activity.

Evaluation of the in vivo mutagenic potential of hydroalcoholic extracts of the northern highbush blueberry (Vaccinium corymbosum L. Ericales, Ericaceae) on peripheral blood cells of Swiss mice (Mus musculus Rodentia, Muridae)

The northern highbush blueberry (Vaccinium corymbosum L. Ericales, Ericaceae) is very rich in anthocyanins, natural pigments which have strong antioxidant properties and potential health benefits, resulting in the worldwide use the blueberry as a medicinal plant. We investigated the mutagenic potential of simple hydroalcoholic extracts of V. corymbosum acutely administrated by gavage to Swiss mice at doses of 1 g kg-1, 1.5 g kg-1 and 2 g kg-1. Peripheral blood cells were collected 4 h and 24 h post-gavage and assessed by the alkaline comet assay, with further blood samples being collected at 48 h and 72 h for assessment using the micronucleus (MN) assay. Our results show that the V. corymbosum extracts did not induce any statistically significant increase in the average amount of DNA damage in peripheral blood leukocytes. However, we did record a significant increase in the frequency of micronucleated polychromatic erythrocytes at the three doses tested.