In vitro assessment of the cytotoxic, apoptotic, and mutagenic potentials of Isatin

Isatin (1H-indole-2,3-dione) is a chemical found in various medicinal plant species and responsible for a broad spectrum of pharmacological and biological properties that may be beneficial to human health, as an anticonvulsant, antibacterial, antifungal, antiviral, and anticancer agent. The aim of the present study was to determine in vitro the cytotoxic, mutagenic, and apoptotic effects of isatin on CHO-K1 and HeLa cells using the MTT viability assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide), micronucleus (MN) test, apoptosis index, and nuclear division index (NDI). The 5 isatin concentrations evaluated in the mutagenicity and apoptosis tests were 0.5, 1, 5, 10, and 50 μM, selected through a preliminary MTT assay. Positive (doxorubicin, DXR) and negative (phosphate buffered saline, PBS) control groups were also included in the analysis. Isatin did not exert a mutagenic effect on CHO-K1 after 3 and 24 h of treatment or on HeLa cells after 24 h. However, 10 and 50 μM concentrations inhibited cell proliferation and promoted apoptosis in both CHO-K1 and HeLa cells. Data indicate that the cytotoxic, apoptotic, and antiproliferative effects of isatin were concentration independent and cell line independent. The authors thank Profa Dra Eiko Nakagawa Itano for the use the spectrophotometer and the Conselho Nacional para o Desenvolvimento Científico e Tecnológico for master's scholarships to P. M. Cândido-Bacani and grants to T. R. Calvo, W. Vilegas, E. A. Varanda and I. M. S. Cólus. The Conselho Nacional para o Desenvolvimento Científico e Tecnológico provided funding for this study. © 2013 Taylor & Francis Group, LLC.

Use of grape polyphenols against carcinogenesis: Putative molecular mechanisms of action using in vitro and in vivo test systems

Polyphenols are present in foods and beverages and are related to sensorial qualities such as color, bitterness, and astringency, which are relevant in wine, tea, grape juice, and other products. These compounds occur naturally in forms varying from simple phenolic acids to complex polymerized tannins. Thus, it is reasonable to expect that grape-derived products elaborated in the presence of skins and seeds, such as wine and grape juice, are natural sources of flavonoids in the diet. Carcinogenesis is a multistep process that is characterized by genetic, epigenetic, and phenotypic changes. With increasing knowledge of these mechanisms, and the conclusion that most cases of cancer are preventable, efforts have focused on identifying the agents with potential anticancer properties. The use of grape polyphenols against the carcinogenesis process seems to be a suitable alternative for either prevention and/or therapeutic purposes. The aim of this article is to show the molecular data generated from the use of grape polyphenols against carcinogenesis using in vivo and in vitro test systems. © Mary Ann Liebert, Inc. and Korean Society of Food Science and Nutrition.

Characterization of proanthocyanidins from Parkia biglobosa (Jacq.) G. Don. (Fabaceae) by flow injection analysis - Electrospray ionization ion trap tandem mass spectrometry and liquid chromatography/electrospray ionization mass spectrometry

The present study investigates the chemical composition of the African plant Parkia biglobosa (Fabaceae) roots and barks by Liquid Chromatography - Electrospray Ionization and Direct Injection Tandem Mass Spectrometry analysis. Mass spectral data indicated that B-type oligomers are present, namely procyanidins and prodelphinidins, with their gallate and glucuronide derivatives, some of them in different isomeric forms. The analysis evidenced the presence of up to 40 proanthocyanidins, some of which are reported for the first time. In this study, the antiradical activity of extracts of roots and barks from Parkia biglobosa was evaluated using DPPH method and they showed satisfactory activities.

Anti-inflammatory intestinal activity of Arctium lappa L. (Asteraceae) in TNBS colitis model

Ethnopharmacological relevance: In Brazilian traditional medicine, Arctium lappa (Asteraceae), has been reported to relieve gastrointestinal symptoms. Aim of the study: In the present study, we investigated the effects of the lactone sesquiterpene onopordopicrin enriched fraction (ONP fraction) from Arctium lappa in an experimental colitis model induced by 2,4,6 trinitrobenzene sulfonic acid and performed experiments to elucidate the underlying action mechanisms involved in that effect. Materials and methods: ONP fraction (25 and 50 mg/kg/day) was orally administered 48, 24 and 1 h prior to the induction of colitis and 24 h after. The inflammatory response was assessed by gross appearance, myeloperoxidase (MPO) activity, tumor necrosis factor alpha (TNF-α) levels and a histological study of the lesions. We determined cyclooxygenase (COX)-1 and -2 protein expressions by western blotting and immunohistochemistry assays. Results: TNBS group was characterized by increased colonic wall thickness, edema, diffuse inflammatory cell infiltration, increased MPO activity and TNF-α levels. On the contrary, ONP fraction (25 and 50 mg/kg) treatment significantly reduced the macroscopic inflammation scores (p<0.05 and p<0.01, respectively) and morphological alterations associated with an increase in the mucus secretion. Similarly, the degree of neutrophil infiltration and the cytokine levels were significantly ameliorated. Moreover, COX-2 expression was up regulated in TNBS-treated rats. In contrast, ONP fraction (50 mg/kg) administration reduced COX-2 overexpression. Conclusions: We have shown that the ONP fraction obtained from Arctium lappa exert marked protective effects in acute experimental colitis, confirming and justifying, at least in part, the popular use of this plant to treat gastrointestinal diseases. © 2013 Elsevier B.V. All rights reserved.

Effects of Ginkgo biloba on chemically-induced mammary tumors in rats receiving tamoxifen

Background: Ginkgo biloba extract (GbE) is used extensively by breast cancer patients undergoing treatment with Tamoxifen (TAM). Thus, the present study investigated the effects of GbE in female Sprague-Dawley (SD) rats bearing chemically-induced mammary tumors and receiving TAM.Methods: Animals bearing mammary tumors (≥1 cm in diameter) were divided into four groups: TAM [10 mg/kg, intragastrically (i.g.)], TAM plus GbE [50 and 100 mg/kg, intraperitoneally (i.p.)] or an untreated control group. After 4 weeks, the therapeutic efficacy of the different treatments was evaluated by measuring the tumor volume (cm3) and the proportions of each tumor that were alive, necrotic or degenerative (mm2). In addition, labeling indexes (LI%) were calculated for cell proliferation (PCNA LI%) and apoptosis (cleaved caspase-3 LI%), expression of estrogen receptor-alpha (ER-α) and p63 biomarkers.Results: Overall, the tumor volume and the PCNA LI% within live tumor areas were reduced by 83% and 99%, respectively, in all TAM-treated groups when compared to the untreated control group. GbE treatment (100 mg/kg) reduced the proportions of live (24.8%) and necrotic areas (2.9%) (p = 0.046 and p = 0.038, respectively) and significantly increased the proportion of degenerative areas (72.9%) (p = 0.004) in mammary tumors when compared to the group treated only with TAM. The expression of ER-α, p63 and cleaved caspase-3 in live tumor tissues was not modified by GbE treatment.Conclusions: Co-treatment with 100 mg/kg GbE presented a slightly beneficial effect on the therapeutic efficacy of TAM in female SD rats bearing mammary tumors. © 2013 Dias et al.; licensee BioMed Central Ltd.

Evaluation of estrogenic, antiestrogenic and genotoxic activity of nemorosone, the major compound found in brown Cuban propolis

Background: Brown propolis is the major type of propolis found in Cuba; its principal component is nemorosone, the major constituent of Clusia rosea floral resins. Nemorosone has received increasing attention due to its strong in vitro anti-cancer action. The citotoxicity of nemorosone in several human cancer cell lines has been reported and correlated to the direct action it has on the estrogen receptor (ER). Breast cancer can be treated with agents that target estrogen-mediated signaling, such as antiestrogens. Phytoestrogen can mimic or modulate the actions of endogenous estrogens and the treatment of breast cancer with phytoestrogens may be a valid strategy, since they have shown anti-cancer activity.Methods: The aim of the present investigation was to assess the capacity of nemorosone to interact with ERs, by Recombinant Yeast Assay (RYA) and E-screen assays, and to determine by comet assay, if the compound causes DNA-damaging in tumoral and non-tumoral breast cells.Results: Nemorosone did not present estrogenic activity, however, it inhibited the 17-β-estradiol (E2) action when either of both methods was used, showing their antiestrogenicity. The DNA damage induced by the benzophenone in cancer and normal breast cells presented negative results.Conclusion: These findings suggest that nemorosone may have therapeutic application in the treatment of breast cancer. © 2013 Camargo et al.; licensee BioMed Central Ltd.

Evaluation of sample preparation procedures and krypton as an interference standard probe for arsenic speciation by HPLC-ICP-QMS

Different conditions of extraction using water, a methanol-water mixture and nitric acid solutions were evaluated for speciation of As(iii), As(v), DMA and MMA in plant samples that previously received As(v) after being sown and emergence was investigated. Microwave-assisted extraction (MAE) using diluted nitric acid solutions was also performed for arsenic extraction from chicken feed samples. The separation and determination of arsenic species were performed using HPLC-ICP-MS. The interference standard method (IFS) using 83Kr+ as the IFS probe was employed to minimize spectral interferences caused by polyatomic species, such as 40Ar 35Cl+. The extraction procedures tested presented adequate extraction efficiencies (90%), and the four arsenic species evaluated were found in plant samples. Extractions with diluted nitric acid solution at 90 °C were the most efficient strategy, with quantitative recoveries for all four As species in plant tissues. On the other hand, the methanol-water mixture was the solvent with the lowest extraction efficiency (50-60%). For chicken feed samples, MAE at 100 °C for 30 min resulted in an extraction efficiency of 97% and only As(v) was found, without any species interconversion. The IFS method contributed to improving precision and limits of detection and quantification for all tested extraction procedures. Significant improvements on accuracy were obtained by applying the IFS method and recoveries between 77 and 94%, and 82 and 93% were obtained for plant extracts and chicken feed samples, respectively. This journal is © 2013 The Royal Society of Chemistry.

Eficácia de extratovegetais em nematódeos parasitas: avaliação invitro em Haemonchus contortud e avaliação in vitro em Strongyloides venezuelensis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise multielementar da mucosa gástrica de roedores tratados com Alchornea glandulosa, Davilla elliptica e Davilla nitida pela técnica de fluorescência de raios-x por reflexão total

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do extrato aquoso de Casearia sylvestris sobre a neutralização e regeneração da mionecrose induzida pelo veneno da Bothrops jaracussu em camundongos: estudo morfológico e funcional

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Prospecção química e avaliação das atividades e alelopática de Myrcia bella Cambess

Pós-graduação em Ciências Biológicas (Botânica) - IBB

Potencial de atividade antimicrobiana in vitro de extratos vegetais do cerrado frente estirpes de Staphylococcus aureus

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Determinação da atividade anti Mycobacterium tuberculosis de metabólitos bioativos de fungos endofíticos empregando a técnica do MABA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação in vitro da atividade antimicrobiana de associações de extratos de Araçá (Psidium cattleianum) e hidróxido de cálcio frente a biofilme multiespécie de Enterococcus faecalis e Candida albicans

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da resposta tecidual dos extratos vegetal aquoso e hidroalcoólico de Aroeira (Astronium urundeuva) pela análise edemogênica e histopatológica em rato

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)