The toxicity of Aspidosperma subincanum to MCF7 cells is related to modulation of oxidative status and proinflammatory pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Cancer is an inflammatory disease because carcinogenesis and tumor progression depend on intrinsic and extrinsic inflammatory pathways. Although species of the genus Aspidosperma are widely used to treat tumors, and there is ethnopharmacological evidence for traditional use of the species A. subincanum as an anti-inflammatory agent, its antineoplastic potential is unknown. AIM OF THE STUDY: To evaluate toxic effects of the indole alkaloid-rich fraction (IAF) of A. subincanum on the MCF7 cell line and identify some of the anti-inflammatory mechanisms involved. MATERIALS AND METHODS: Chromatographic analyses were performed by ultra-high-performance liquid chromatography with electrospray ionization mass spectrometry, and cytotoxic and antiproliferative effects of IAF were verified by MTT and clonogenic assays. Cell cycle alterations were analyzed by measuring DNA content, while propidium iodide and acridine orange staining was performed to determine the type of induced cell death. The expression of apoptosis markers and proteins involved in cell proliferation and survival pathways was analyzed by immunoblotting, RT-qPCR, and ELISAs. Interference with redox status was investigated using a DCFH-DA probe and by measuring catalase activity. RESULTS: Chromatographic analyses showed that IAF is a complex mixture containing indole alkaloids. IAF selectively exerted toxic and antiproliferative effects, elevating the Bax/Bcl-xL ratio and inducing apoptosis in MCF7 cells. IAF decreased intracellular reactive oxygen species levels and increased catalase activity, while reducing the IL-8 level and suppressing COX-2 expression. CONCLUSIONS: IAF induces apoptosis in MCF7 cells by suppressing COX-2 expression while reducing IL-8 levels and intracellular content of reactive oxygen species.

Influence of rosmarinic acid and Salvia officinalis extracts on melanogenesis of B16F10 cells

Melanin is a photoprotective skin pigment, and pathologies characterized by hypo or hyperpigmentation are common. New compounds that regulate melanogenesis are, therefore, opportune, and many natural products with this property, as polyphenols, have been described. Salvia officinalis L., Lamiaceae, is a widely used food spice that contains high amounts of phenol derivates, including rosmarinic acid. The aim of this work was to evaluate the contribution of rosmarinic acid in the melanogenic activity of sage extracts. Fluid and aqueous extracts of sage and purified rosmarinic acid were assayed for B16F10 cytotoxicity and, then, evaluated on melanin production and tyrosinase activity. While sage extracts showed a concentration-dependent ability to significantly increase melanin production without necessarily changing the enzymatic activity, rosmarinic acid showed a dual behavior on melanogenesis, increasing melanin biosynthesis and tyrosinase activity at low concentrations and decreasing it at higher levels. Rosmarinic acid may collaborate with sage extracts activity on melanogenesis, although other compounds may be involved. This is the first time that a dual action of rosmarinic acid on melanogenesis is reported, which may be useful in further studies for therapeutic formulations to treat skin pigmentation disorders.

Dengue-2 structural proteins associate with human proteins to produce a coagulation and innate immune response biased interactome.

BACKGROUND: Dengue virus infection is a public health threat to hundreds of millions of individuals in the tropical regions of the globe. Although Dengue infection usually manifests itself in its mildest, though often debilitating clinical form, dengue fever, life-threatening complications commonly arise in the form of hemorrhagic shock and encephalitis. The etiological basis for the virus-induced pathology in general, and the different clinical manifestations in particular, are not well understood. We reasoned that a detailed knowledge of the global biological processes affected by virus entry into a cell might help shed new light on this long-standing problem. METHODS: A bacterial two-hybrid screen using DENV2 structural proteins as bait was performed, and the results were used to feed a manually curated, global dengue-human protein interaction network. Gene ontology and pathway enrichment, along with network topology and microarray meta-analysis, were used to generate hypothesis regarding dengue disease biology. RESULTS: Combining bioinformatic tools with two-hybrid technology, we screened human cDNA libraries to catalogue proteins physically interacting with the DENV2 virus structural proteins, Env, cap and PrM. We identified 31 interacting human proteins representing distinct biological processes that are closely related to the major clinical diagnostic feature of dengue infection: haemostatic imbalance. In addition, we found dengue-binding human proteins involved with additional key aspects, previously described as fundamental for virus entry into cells and the innate immune response to infection. Construction of a DENV2-human global protein interaction network revealed interesting biological properties suggested by simple network topology analysis. CONCLUSIONS: Our experimental strategy revealed that dengue structural proteins interact with human protein targets involved in the maintenance of blood coagulation and innate anti-viral response processes, and predicts that the interaction of dengue proteins with a proposed human protein interaction network produces a modified biological outcome that may be behind the hallmark pathologies of dengue infection.

Association between malnutrition, integrin expression and impaired granulocyte adhesion in chronically hemodialyzed patients.

BACKGROUND: The relationship between malnutrition in hemodialysis (HD) patients with a chronic inflammatory condition and the expression levels of leukocyte integrins and their adhesiveness to fibronectin was investigated. METHODS: Subjective global assessment, albumin and body mass index were used as nutritional markers to group malnourished (MP) and eutrophic (EP) patients. C-reactive protein was used as an inflammation marker. LFA-1, VLA-4 and VLA-5 expression levels on circulating leukocytes before and after HD were flow cytometrically measured; and their adhesiveness, through immobilized fibronectin. RESULTS: MPs showed significantly higher VLA-5 expression on granulocytes, when compared with healthy individuals (HPs) as controls (13.7% +/- 2.3% vs. 5.0% +/- 1.1%; p=0.005), particularly after HD (25.8% +/- 4.1%; p<0.001). They also presented a significantly lower ability to adhere to fibronectin when compared with EPs, before HD (48.8% +/- 1.5% vs. 62.3% +/- 0.7%; p<0.001) and after HD (50.6% +/- 1.2% vs. 65.7% +/- 1.4%; p<0.0001). Increased numbers of circulating immature neutrophils were observed only in MPs. CONCLUSIONS: Although presenting higher VLA-5 expression, malnutrition in HD patients is associated with impairment of the adhesive capacity of circulating leukocytes, particularly younger neutrophils, which may contribute to the chronic inflammatory status of these patients.

Potencial antiinflamatório de Annona glabra, Annonaceae / Anti-inflammatory potential of Annona glabra, Annonaceae

Annona glabra Linneau, Annonaceae, é uma árvore de pequeno porte encontrada em todo território brasileiro, principalmente nas áreas costeiras e conhecida popularmente como araticum-do-brejo e araticum-bravo. Este trabalho teve como objetivos investigar os efeitos do extrato de A. glabra e do ácido caurenóico dele purificado sobre a migração de granulócitos humanos e seu potencial imunomodulatório. Os resultados demonstraram que o extrato de A. glabra inibe a migração natural de granulócitos, de acordo com a dose, sugerindo potencial antiinflamatório, enquanto o ácido caurenóico demonstrou estimulá-la de forma significativa. Em contraste, nenhum efeito foi observado com relação a imunomodulação. Os efeitos apresentados ainda não foram descritos e, dessa forma, contribuem para ampliar a lista de atividades biológicas descritas não só do extrato de A. glabra, como também para o ácido caurenóico.

Annona glabra Linneau, Annonaceae, is a small tree that grows over the Brazilian territory particularly in its coast, and is known as "araticum-do-brejo" and "araticum-bravo". The aim of this study was to evaluate the effects of the extract of A. glabra and its purified kaurenoic acid on the locomotion of human granulocytes and their immunomodulatory potential. The results herein presented showed a dose-dependent inhibition of the granulocyte migration for the extract, suggesting an anti-inflammatory activity, in contrast with a striking stimulation observed for the kaurenoic acid. When focusing immunomodulation properties, no activity could be drawn. The effects presented in this work are reported for the first time and extend the list of biological activities already described for the A. glabra extract as well as for the kaurenoic acid.

Human erythrocytes as a system for evaluating the antioxidant capacity of vegetable extracts.

Free radicals are fairly unstable and highly reactive substances, able of causing oxidation and sometimes-irreversible damage to cells, compromising their function. The Brassicaceae family has many important species for the regular human diet as they provide several antioxidant constituents. In this study, the antioxidant potential of the hydroethanolic extracts prepared from the edible parts of kale, broccoli, and radish was investigated in vitro using human erythrocytes under oxidative stress imposed by phenylhydrazine as an experimental model, in which the methemoglobin levels were measured. When the results were compared with the antioxidant capacity shown by the traditional 2,2-diphenyl-2-picrylhydrazyl hydrate free radical and phosphomolybdenum complex methods, the extracts tested showed significant and correspondent antioxidant activity. Broccoli extract presented the highest antioxidant activity, followed closely by the kale, whereas the radish extract occupied the lowest position. The results derived from the human erythrocyte system have shown it as an alternative method for evaluating the antioxidant properties of vegetable extracts.

Leishmanicidal, antibacterial, and antioxidant activities of Caryocar brasiliense Cambess leaves hydroethanolic extract / Atividades leishmanicida, bactericida e antioxidante do extrato hidroetanólico das folhas de Caryocar brasiliense Cambess

The antimicrobial and antioxidant activities of the hydroethanolic extract from Caryocar brasiliense leaves were evaluated. The extract showed leishmanicidal effect against Leishmania amazonensis promastigote forms and bactericidal activity against some pathogenic bacteria. The extract also showed relevant antioxidant activity, similar to that of vitamin C and rutin.

As atividades antimicrobiana e antioxidante do extrato hidroetanólico das folhas de Caryocar brasiliense foram estudadas. O extrato demonstrou efeito leishmanicida sobre formas promastigotas de Leishmania amazonensis e atividade bactericida sobre estirpes de bactérias patogênicas para o homem. Além disso, o extrato demonstrou relevante capacidade antioxidante, similar às atividades da vitamina C e da rutina.

A citometria de fluxo como instrumento de avaliação da atividade imunomodulatória de extratos e substâncias isoladas de plantas medicinais / Flow cytometry as instrument for evaluating the immunopotential of medicinal plant extracts and their isolated compounds

A citometria de fluxo vem se consolidando como metodologia para vários estudos de atividade celular e, nesse trabalho, ela foi empregada para avaliar as ações da fitohemaglutinina, dos alcalóides vimblastina e vindolina e dos extratos de Chamomilla recutita (L.) Rauschert, Bauhinia microstachya (Raddi) Machr. e Himatanthus lancifolius (Muell. Arg.) Woodson, conhecidos popularmente no Brasil como camomila, escada-de-macaco e agoniada, respectivamente, sobre a imunomodulação de células mononucleares humanas, comparando-se o desempenho obtido com as alterações morfológicas relacionadas à ativação e proliferação dessas células in vitro. Os resultados demonstram que foi possível identificar, pela metodologia proposta, os efeitos proliferativos estimulantes já descritos para a fitohemaglutinina e para o extrato de C. recutita, assim como para o extrato de B. microstachya, observado pela primeira vez nesse trabalho. A conhecida atividade inibitória da vimblastina sobre a proliferação de linfócitos induzida por fitohemaglutinina, em contraste como a ausência de efeitos da vindolina, também puderam ser evidenciadas. Efeito inibitório foi observado para o extrato de H. lancifolius devido à sua ação tóxica sobre o sistema. Os resultados apresentados sugerem que a citometria de fluxo pode ser usada como uma alternativa metodológica quando se deseja investigar a ação de substâncias puras ou de extratos de plantas sobre a imunomodulação de células mononucleares humanas.

Flow cytometry has been widely applied for studying several cellular activities. In this work it has been used to evaluate the effects of phytohemagglutinin, vinblastine, and vindoline upon human mononuclear cells immunomodulation. The same protocol was used to investigate the effects of extracts prepared from Chamomilla recutita (L.) Rauschert, Bauhinia microstachya (Raddi) Machr., and Himatanthus lancifolius (Muell. Arg.) Woodson, plants popularly known in Brazil as camomila, escada-de-macaco, and agoniada, respectively. The activity was then compared with the in vitro cellular morphological changes. By the results herein presented, the proposed method allowed the identification of the already known phytohemagglutinin and C. recutita extract proliferative effects, as well as for the B. microstachya extract, reported for the first time. The inhibition of vinblastine upon the proliferation of phytohemagglutin-stimulated cells and the lack of effects of vindoline were also evident. Exposition to H. lancifolius extract has led to inhibition of lymphocyte proliferation as a result of the high toxicity of the extract upon the system. Results presented strongly suggest flow cytometry as a useful instrument to evaluatethe immunomodulation effects of pure compounds or complex mixtures such as plant extracts upon human mononuclear cells.