RESUMO

Some plants popularly employed for the treatment of peptic ulcers have proved to be attractive sources of new drugs. Despite extensive research, the pharmacological and toxicological potentials of these plants are not fully understood. In this context, the aim of this work was to analyze the multielemental composition of the methanolic extracts of three of those plants, Alchornea glandulosa (AG), Davilla elliptica (DE) and Davilla nitida (DN), with the intention of contributing to the understanding of the mechanisms of action of these extracts. For this purpose, we used the analytical technique of total reflection X-ray fluorescence (TXRF) by synchrotron radiation at the Brazilian Synchrotron Light Source (LNLS/CNPEM). It was possible to determine the concentrations of the elements: P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb and Br in all of the samples. Selenium (Se) was detected only in the DN extract. An inverse relationship between the concentrations of elements with proven effectiveness and the gastroprotective activity of extracts considering induction protocols with ethanol and non-steroidal anti-inflammatory drugs (NSAIDs) was obtained. This data suggests that the function of the extract is not only associated with providing the elements for restoring the gastric mucosa but that it also promotes the displacement of these elements from other parts of the mucosa to the damaged area. Correlations between the concentrations of the elements were also obtained. In the DE extract, which is the most effective extract for both induction protocols, the obtained correlations were above 70% among almost all of the elements, and no anticorrelations were found. For the other two extracts, in the less effective extract (AG) anticorrelations above 70% were predominantly found. Meanwhile, in the DN extract, a few high anticorrelations were found, which may explain its intermediate stage of effectiveness.

RESUMO

Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity.

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RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Davilla elliptica St.-Hil. (Dilleniaceae) is a medicinal plant traditionally used in Brazil to treat inflammatory processes, to relieve pain, as diuretic, gastro- and hepatoprotective agents. AIM OF THE STUDY: To undertake the fractionation of the ethanolic extract from Davilla elliptica leaves guided by an antinociceptive assay. MATERIALS AND METHODS: The antinociceptive activity was evaluated through the formalin test in mice. Extract fractionation was performed by percolation through silica gel and partition between immiscible solvents, followed by successive column chromatography over Sephadex LH-20 and preparative RP-HPLC. Structure elucidation of the isolated compound was accomplished by spectroscopic data. RESULTS: The EtOAc and MeOH fractions derived from the crude extract reduced significantly the licking time in the late phase of the formalin test. The bioguided fractionation of the MeOH fraction resulted in the isolation of myricetin-3-O-ß-galactopyranoside, which produced significant inhibition on nociception induced by formalin (ID50=0.26 mg/kg; p.o.). CONCLUSIONS: These results point out that myricetin-3-O-ß-galactopyranoside contributes for the antinociceptive effect of Davilla elliptica extract, a constituent considerably more potent than diclofenac, employed as reference drug.

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RESUMO

As características farmacognósticas das folhas de Davilla elliptica A. St.-Hil. e D. rugosa Poir., Dilleniaceae, foram determinadas com objetivo de auxiliar na identificação taxonômica e no controle de qualidade das drogas vegetais e de produtos fitoterápicos. A espécie D. elliptica é um arbusto ereto, que ocorre naturalmente no cerrado e D. rugosa é um trepadeira lenhosa de beira de mata. Ambas são conhecidas popularmente como lixeirinha, sambaibinha e cipó-caboclo, empregadas na medicina tradicional como antiinflamatória e antiúlcera. As características microscópicas observadas em D. rugosa tais como tricomas estrelados e esclereídes no mesofilo e em D. elliptica de idioblastos contendo mucilagem e endoderme, são parâmetros que poderão ser utilizados na diferenciação das espécies. Os teores obtidos nos ensaios de pureza e nos doseamentos de taninos (9,4 por cento e 7,2 por cento), flavonoides (0,46 por cento e 0,9 por cento) e mucilagens (2,2 por cento e 4,1 por cento) de ambas as espécies, podem contribuir no controle de qualidade das drogas vegetais uma vez que são usadas indistintamente na produção de fitoterápicos.

The characters pharmacognostics of leaves of Davilla elliptica St. Hil. and Davilla rugosa Poir. of Dilleniaceae family were determinated for aiming in taxonomic and quality control of vegetable drugs and phytotherapic produtcs. The specie of D. elliptica is an erect shrub, that occurs naturally in cerrado and D. rugosa is a scandent shrub of forest edge. Both are populary known as "lixeirinha", "sambaibinha" and "cipó-caboclo" and used in popular medicine as anti-inflammatory and antiulcer. The microscopic characteristics observed like strellate trichomes and sclereids in the mesophyll in D. rugosa and the idioblasts with mucilage and endodermis in D. elliptica are parameter that will be used to differentiate the species. The content obtained in tests of purity and the tannins (9.4 percent and 7.2 percent), flavonoids (0.46 percent and 0.9 percent) and mucilage (2.2 percent and 4.1 percent) of both species help in quality control of vegetable drugs since they are indistinctly used in production of phytotherapics.

RESUMO

Mycobacterium tuberculosis is responsible for over 8 million cases of tuberculosis (TB) annually. Natural products may play important roles in the chemotherapy of TB. The immunological activity of Davilla elliptica chloroform extract (DECE) was evaluated in vitro by the determination of hydrogen peroxide (H2O2), nitric oxide (NO), and tumor necrosis factor-alpha (TNF-alpha) release in peritoneal macrophages cultures. DECE was also tested for its antimycobacterial activity against M. tuberculosis using the microplate alamar blue assay. DECE (50, 150, 250 mug/ml) stimulated the production of H2O2 (from 1,79 ± 0,23 to 7,27 ± 2,54; 15,02 ± 2,86; 20,5 ± 2,1 nmols) (means ± SD), NO (from 2,64 ± 1,02 to 25,59 ± 2,29; 26,68 ± 2,41; 29,45 ± 5,87 mumols) (means ± SD) and TNF-alpha (from 2,44 ± 1,46 to 30,37 ± 8,13; 38,68 ± 1,59; 41,6 ± 0,90 units/ml) (means ± SD) in a dose-dependent manner and also showed a promising antimycobacterial activity with a minimum inhibitory concentration of 62,5 mug/ml. This plant may have therapeutic potential in the immunological and microbiological control of TB.

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RESUMO

Davilla elliptica St.-Hil. é empregada popularmente no tratamento de hemorróidas, diarréias e ferimentos. O propósito deste trabalho foi realizar o estudo farmacognóstico de folhas de D. elliptica de dois locais do Estado de Goiás. Cortes paradérmicos e transversais foram submetidos a técnicas usuais de microscopia óptica. As folhas de D. elliptica são hipoestomáticas, sendo os estômatos predominantemente paracíticos. Na epiderme observam-se tricomas unicelulares em ambas faces. O mesofilo é isobilateral e apresenta idioblastos cristalíferos. O sistema vascular na nervura principal é constituído por três feixes vasculares, formando uma estrutura circular. No pecíolo o sistema vascular apresenta uma estrutura circular formada, provavelmente, pela união de vários feixes vasculares. O material pulverizado foi submetido a testes de prospecção fitoquímica, de pureza e quantitativo. Foi constatada a presença de taninos, cumarinas, resinas, flavonóides, saponinas, esteróides e triterpenóides. Os teores de cinzas totais foram de 10,32 por cento e 12,26 por cento; os de cinzas insolúveis em ácido, 7,46 por cento e 9,68 por cento; e os de umidade, 9,92 por cento e 9,50 por cento. Os teores de flavonóides totais foram de 1,20 por cento e 1,48 por cento, e os de taninos 9,89 por cento e 13,96 por cento. Devido ao número reduzido de amostras, não é possível afirmar, através deste estudo, que o perfil farmacognóstico de D. elliptica seja influenciado por fatores abióticos.

Davilla elliptica St.-Hil. is popularly used in the treatment of hemorrhoid, diarrhea and wounds. The aim of this work was to characterize pharmacognosticaly two leaves samples of D. elliptica. Paradermal and transversal sections had been submitted the usual techniques of optical microscopy. The leaves of D. elliptica are hypostomatics, and the stomata predominantly paracytic. In both epidermis were observed unicellular non-glandular trichomes. The mesophyll is isolateral and shows idioblasts with crystals in raphide. The vascular system in the midrib is constituted by three vascular bundles, forming a circular structure. The petiole shows a circular structure probably formed by union of many vascular bundles localized in the central region. The powdered plant material was submitted to tests of phytochemical prospection, of purity and quantitative. There had been evidenced the presence of tannins, coumarins, resins, flavonoids, saponins and steroids. The content of total ashes was of 10,32 percent and 12,26 percent, insoluble in acid of 7,46 percent and 9,68 percent; the humidity of 9,92 percent and 9,50 percent. The flavonoids contents was of 1,20 percent and 1,48 percent; the tannins contents was of 9,89 percent and 13,96 percent. Because of the reduced number of samples, it was not possible to affirm through this study that the pharmacognostic profile de D. elliptica is influenced by abiotics factors.

RESUMO

Davilla elliptica St. Hill ("lixinha"), family Dilleniaceae, is commonly used in the Brazilian folk medicine as purgative and stimulant. This work evaluated the antimicrobial activity of the methanol and chloroform extracts of the leaves and barks of D. elliptica using the disc-diffusion method. The results obtained showed that the methanolic extracts of the leaves and barks presented antimicrobial activity against the tested microorganisms.

RESUMO

Plantas têm contribuído no tratamento da maioria das doenças. Considerando a importância terapêutica das plantas medicinais, foi avaliada a atividade imunológica dos extratos metanólico e etanólico de Davilla elliptica. Macrófagos estão envolvidos em todos estágios da resposta imune, podendo liberar componentes como: peróxido de hidrogênio (H2O2), óxido nítrico (NO) e fator de necrose tumoral-alfa (TNF-alfa). A estimulação dos macrófagos foi avaliada pela determinação de H2O2, NO e TNF-alfa em culturas de macrófagos peritoneais de camundongos na presença dos extratos da D. elliptica. IC50 foi determinado através de ensaio utilizando MTT. Os estudos fitoquímicos realizados mostraram a presença de flavonóides derivados da quercetina e miricetina entre outros compostos. A produção de H2O2 não foi muito expressiva em ambos extratos, contudo a de NO foi significativa. Os dois extratos induziram a produção de TNF-alfa, sendo que a liberação dessa citocina pelo extrato metanólico foi quase cinco vezes maior do que pelo extrato etanólico. Uma relação entre as sínteses de NO e TNF-alfa foi observada. O aumento na produção de NO está relacionado com a indução de citocinas pró-inflamatórias como TNF-alfa. Analisando os resultados, sugere-se que os extratos metanólico e etanólico de D. elliptica podem modular a ativação de macrófagos.

Plants have contributed in a significant way to the treatment of most of the diseases. Considering the therapeutic importance of the medicinal plants, the immunological activity of the methanolic and ethanolic extract of Davilla elliptica was evaluated. In every stage of the immune response macrophages are involved and they can release many compounds such as hydrogen peroxide (H2O2), nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha). Macrophages stimulation was evaluated by the determination of H2O2, NO and TNF-alpha in peritoneal macrophages cultures of mice in the presence of the D. elliptica extracts. IC50 was determined by MTT assay. The phytochemical study showed flavonoids derived from quercetin and myricetin and other compounds. The production of H2O2 was not very expressive in both extracts, but they presented a significant effect on NO production. The two extracts induced TNF-alpha production, although the methanolic liberated almost five times more TNF-alpha than the ethanolic one. A relationship among the synthesis of NO and TNF-alpha was observed. The increase of NO production is related with the induction of proinflammatory cytokines like TNF-alpha. Analyzing the results, it is suggested that methanolic and ethanolic extract of D. elliptica can modulate macrophage activation.