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-antinflammatory 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 gastricjuice 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 50 mg/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 2000 mg/kg.Conclusions: In conclusion, the results of this study show that caffeic, ferulic, p-coumaric and cinnamic acids display antiulcer activity. (c) 2008 Elsevier B.V. All rights reserved.

Black bean (Phaseolus vulgaris L.) as a protective agent against DNA damage in mice

This study was designed to evaluate the toxicogenetic or protective effect of cooked and dehydrated black beans (Phaseolus vulgaris L.) in bone marrow and peripheral blood cells of exposed mice. The frequency of micronuclei detected using the bone marrow erythrocyte micronucleus test and level of DNA lesions detected by the comet assay were chosen as end-points reflecting mutagenic and genotoxic damage, respectively. Initially, Swiss male mice were fed with a 20% black bean diet in order to detect mutagenic and genotoxic activity. However, no increase in the frequency of bone marrow micronucleated polychromatic erythrocytes (MN PCEs) or DNA lesion in leukocytes was observed. In contrast, received diets containing 1, 10 or 20% of black beans, a clear, but not dose-dependent reduction in the frequency of MN PCEs were observed in animals simultaneously treated with cyclophosphamide, an indirect acting mutagen. Similar results were observed in leukocytes by the comet assay. Commercial anthocyanin was also tested in an attempt to identify the bean components responsible for this protective effect. However, instead of being protective, the flavonoid, at the highest dose administered (50 mg/kg bw), induced primary DNA lesion, as detected by the comet assay. These data indicate the importance of food components in preventing genetic damage induced by chemical mutagens, and also reinforce the role of toxicogenetic techniques in protecting human health. (C) 2003 Elsevier Ltd. All rights reserved.

Protective effects of lemongrass (Cymbopogon citratus STAPF) essential oil on DNA damage and carcinogenesis in female Balb/C mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Natural killer activity in mice infected with rabies virus and submitted to P-acnes (Propionibacterium acnes) as immunomodulator

The natural killer (NK) activity and lethality were evaluated in swiss mice experimentally infected with street rabies virus and submitted to immunomodulation by P. acnes (formerly Corynebacterium parvum). The infected animals were sacrificed at different times and spleen non-adherent cells were obtained through ficoll-hypaque gradient and depletion of glass-adherent cells. Immunosuppression was observed in rabies virus infected mice correlated with lower NK activity in clinically ill animals. Higher NK activity and percentual of survival were observed in the group submitted to P. acnes. The increased survival correlated with higher NK activity induced by P. acnes suggests a protective role of this natural barrier against rabies virus infection in mice. (C) 2000 Elsevier B.V. Ltd. All rights reserved.

Gastric anti-ulcer activity of leaf fractions obtained of polar extract from Wilbrandia ebracteata in mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mechanisms of the Gastric Antiulcerogenic Activity of Anacardium humile St. Hil on Ethanol-Induced Acute Gastric Mucosal Injury in Rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of essential oil obtained from Croton cajucara Benth. on gastric ulcer healing and protective factors of the gastric mucosa

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

SIRT1 Deacetylase Activity and the Maintenance of Protein Homeostasis in Response to Stress: An Overview

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Protective effects of beta-glucan extracted from Agaricus brasiliensis against chemically induced DNA damage in human lymphocytes

beta-Glucans (BGs) are polysaccharides that are found in the cell walls of organisms such as bacteria, fungi, and some cereals. The objective of the present study was to investigate the genotoxic and antigenotoxic effects of BG extracted from the mushroom Agaricus brasiliensis (=Agaricus blazei Murrill ss. Heinemann). The mutagenic activity of BG was tested in single-cell gel electrophoresis assays with human peripheral lymphocytes. In addition, the protective effects against the cooked food mutagen 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and (+/-)-anti-B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), which is the main metabolite of B[a]P, and against ROS (H2O2)-induced DNA damage, were studied. The results showed that the compound itself was devoid of mutagenic activity, and that a significant dose-dependent protective effect against damage induced by hydrogen peroxide and Trp-P-2 occurred in the dose range 20-80 mu g/ml. To investigate the prevention of Trp-P-2-induced DNA damage, a binding assay was carried out to determine whether BG inactivates the amine via direct binding. Since no such interactions were observed, it is likely that BG interacts with enzymes involved in the metabolism of the amine.

Investigation of cytotoxic, apoptosis-inducing, genotoxic and protective effects of the flavonoid rutin in HTC hepatic cells

Rutin is a flavonoid with antioxidant, vasodilatory, anti-inflammatory and immune-stimulating activities. To study the toxicity of rutin and its protective effect, this work investigated the cytotoxic, apoptosis-inducing, genotoxic and protective effects of rutin in HTC cells. In the MTT assay, the highest concentration tested (810 mu M) showed cytotoxicity after 72 h of treatment, where cell viability and cell proliferation was diminished. None of the concentrations of rutin tested induced apoptosis after 24 h treatment. The highest concentration of rutin after 24 h treatment induced DNA damage, shown in the comet assay, but did have a genotoxic effect in the micronucleus test. Rutin was tested against the pro-carcinogenic agent benzo(a)pyrene, at concentrations of 90, 270 and 810 mu M, and was found to reduce induced DNA damage significantly. This protective effect of rutin against a pro-carcinogen, suggests an important biological activity for this compound, which can contribute to human health through the diet. (C) 2010 Elsevier GmbH. All rights reserved.

Protective effects of beta-glucan extracted from barley against benzo[a]pyrene-induced DNA damage in hepatic cell HepG2

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Chemopreventive activity of compounds extracted from Casearia sylvestris (Salicaceae) Sw against DNA damage induced by particulate matter emitted by sugarcane burning near Araraquara, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anticlastogenic activity of aqueous extract of Agaricus blazei in drug-metabolizing cells (HTCs) during cell cycle

The mushroom Agaricus blazei has been extensively investigated because of evidence of its antimutagenic, antitumor, and anticarcinogenic activities. This study investigated the clastogenic and/or anticlastogenic activity of aqueous extract of Agaricus blazei (10% w/v) in drug-metabolizing rat hepatoma tissue cells (HTCs), with continuous treatment and treatment during different phases of the cell cycle. DNA damage was induced utilizing two directacting agents-methyl methane sulfonate and ethyl methane sulfonate-and two indirect-acting agents-2-aminoanthracene and cyclophosphamide. The aqueous extract of A. blazei with either continuous treatment or treatment during different phases of the cell cycle showed clastogenic activity. The results with continuous treatment showed that A. blazei does not protect against DNA damage-inducing agents that are direct acting. Meanwhile, when combined with indirect-acting agents, a protective effect was demonstrated. A protective effect was also found during different phases of the cell cycle when cells were treated with indirect-acting agents. The protective effects against indirect-acting agents (continuous treatment and during the different phases of the cell cycle) suggest that A. blazei may provide some health benefits to the public when used as a functional food.

Anti-inflammatory intestinal activity of Abarema cochliacarpos (Gomes) Barneby & Grimes in TNBS colitis model

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influence of Tumour Condition on the Macrophage Activity in Candida albicans Infection

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)