Potential use of extract of the plant Schwartiza brasiliensis (choisy) bedell ex gir.-Cañas against the toxic effects of the venom of Bothrops jararaca or B. jararacussu.

Envenomation by snakes is a worldwide health public issue, and antivenoms are less efficient in neutralizing local toxic effects. Thus, more efficient therapies to treat patients deserve attention, and plants have been extensively tested. So, the aim of this work was to evaluate the effect of the aqueous fraction of the plant Schwartzia brasiliensis to inhibit some toxic activities of Bothrops jararaca or B. jararacussu venom. S. brasiliensis inhibited coagulant, hemolytic, proteolytic, hemorrhagic, edematogenic, and lethal activities of both venoms, regardless if plant was mixed together with venoms or injected after them as well as the route of administration (intravenous, oral or subcutaneous) of the plant. The S. brasiliensis extract showed no toxicity to mice or red blood cells. Thus, S. brasiliensis may be useful as an alternative treatment for snakebite envenomation and aid antivenom therapy to neutralize relevant toxic activities in patients bitten by Bothrops species.

Pentacyclic triterpenes from Chrysobalanaceae species: cytotoxicity on multidrug resistant and sensitive leukemia cell lines.

Plants are known as important source in the search for new anti-cancer agents. Cytotoxicity-guided fractionation of leaves and fruits from Licania tomentosa Bench and leaves from Chrysobalanus icaco L. resulted in the isolation of betulinic, oleanolic and pomolic acids. These triterpenoids inhibited the growth and induced apoptosis of K562, an erythroleukemia cell line. Most importantly, they also inhibited the proliferation of Lucena 1, a vincristine-resistant derivative of K562 that displays several multidrug resistance (MDR) characteristics. Taken together, our findings emphasize the anti-tumor activity of these triterpenes on leukemia cell lines and call attention to their potential as anti MDR agents.

Composition of the essential oils from leaves of Piper lepturum Kunth (C.DC.) var. lepturum and Piper lepturum var. angustifolium (Miq.) Yunck. from Brasil / Composición de los aceites esenciales de hojas de Piper lepturum Kunth (C.DC.) var. lepturum y Pip

The essential oils of Brazilian Piper lepturum var. lepturum and Piper lepturum var. angustifolium (Piperaceae) were obtained by hydrodistillation and analyzed by flame-detector gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC/MS). According to GC and GC/MS analysis, the essential oils are mostly composed by sesquiterpenes hydrocarbons. beta-Guaiene (29.96 percent) was the principal component in the essential oil of P. lepturum var. lepturum and beta-Bisabolene (17.72 percent) was the principal components in the essential oil of P. lepturum var. angustifolium.

Los aceites esenciales de las especies brasileñas Piper lepturum var. lepturum y Piper lepturum var. angustifolium fueron obtenidos por hidrodestilación y analizados utilizando cromatografía gas líquido con detector de ionización de llama (CG) y cromatografía gas líquido acoplada a un detector de masas (CG/EM). De acuerdo con los análisis de CG y CG/EM, los aceites esenciales muestran como componente principal beta-Guaieno (29,96 por ciento) en el aceite esencial de P. lepturum var. lepturum y beta-Bisaboleno (17,71 por ciento) en el aceite esencial de P. lepturum var. angustifolium.

Cytotoxic and Antiviral Activity of Extracts and Compounds Isolated from Clusia Fluminensis Planch. & Triana (Clusiaceae) / Atividade Citotóxica e Antiviral de Extratos e Compostos Isolados de Clusia Fluminensis Planch. & Triana (Clusiaceae)

The worldwide distribution of herpes simplex virus type 1 (HSV-1) allied to the emergence of resistant strains makes necessary and urgent the search and development of new substances capable of preventing and treating HSV-1 infections. Studies demonstrate synergy between genital herpes and human immunodeficiency virus type 1 (HIV-1), which represents a major concern for global public health. Objective: The objective of this study was to evaluate the activity of crude extracts and isolated substances from C. fluminensis in the in vitro replication of the HSV-1 virus and HIV-1-RT activity. Methods: This study evaluated the activity of extracts and isolated compounds from Clusia fluminensis Planch. & Triana against HSV-1 using Vero cells in culture and against HIV-1 using a recombinant reverse transcriptase enzyme (HIV -1 RT). The percentage of inhibition against HSV-1 was determined from viral lysis plaque reduction assay, and the anti-HIV-1-RT test was performed by a fluorimetric assay. It was also evaluated the cytotoxic activity of the samples using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. Results: The crude extracts showed high percentage of inhibition against HSV-1, reaching 81.4 to 100.0% inhibition in non-cytotoxic concentration (50 µg/mL). The isolated compounds, lanosterol and clusianone, demonstrated 100% inhibition in non-cytotoxic concentration (50 µg/mL). We also examined the effects of the extracts and isolates on the activity of the HIV-1-RT. Among the crude extracts, only the methanolic extract of leaves and methanolic extract of stems showed inhibitory activity against HIV-1-RT. Regarding the isolated compounds, lanosterol showed a moderate activity. Conclusion: Our data demonstrate that extracts and isolates compounds Clusia fluminensis Planch. & Triana have promising antiviral activity inhibiting HSV-1 replication and HIV-1 by inhibiting the anti-RT activity.

A distribuição mundial do vírus herpes simplex tipo 1 (HSV-1) aliada ao surgimento de cepas resistentes torna necessária e urgente a busca e o desenvolvimento de novas substâncias capazes de prevenir e tratar infecções HSV-1. Estudos demonstram sinergia entre herpes genital e vírus da imunodeficiência humana tipo 1 (HIV-1), o que representa uma grande preocupação para a saúde pública global. Objetivo: O objetivo deste estudo foi avaliar a atividade de extratos brutos e substâncias isoladas de Clusia fluminensis Planch. & Triana na replicação in vitro do vírus HSV-1 e na atividade anti HIV-1-RT. Métodos: Este estudo avaliou a atividade de extratos e substâncias isoladas de Clusia fluminensis Planch. & Triana contra o HSV-1 utilizando células Vero em cultura e contra o HIV-1 utilizando a enzima transcriptase reversa recombinante (HIV-1 RT). A porcentagem de inibição contra o HSV-1 foi determinada a partir do ensaio de redução de placas de lise viral, e o ensaio anti-HIV-1 RT foi realizado por um ensaio fluorimétrico. Também foi avaliada a atividade citotóxica das amostras utilizando MTT [brometo de 3- (4,5-dimetiltiazol-2-il) -2,5-difeniltetrazólio]. Resultados: Os extratos demonstraram elevada percentagem de inibição contra o HSV-1, atingindo 81,4 a 100,0% de inibição em concentração não citotóxica (50 µg/mL). Os compostos isolados, lanosterol e clusianona, demonstraram 100% de inibição em concentração não citotóxica (50 µg/mL). Examinamos também os efeitos dos extratos e isolados sobre a atividade anti-HIV-1 RT. Entre os extratos brutos, apenas o extrato metanólico das folhas e caules apresentaram atividade anti-HIV-1 RT. Em relação aos compostos isolados, lanosterol mostrou uma atividade moderada. Conclusão: Nossos dados demonstram que os extratos e compostos isolados de Clusia fluminensis Planch. & Triana possuem atividade antiviral promissora inibindo a replicação do HSV-1 e HIV-1 através da inibição da atividade anti-RT.

Natural triterpenoids from Cecropia lyratiloba are cytotoxic to both sensitive and multidrug resistant leukemia cell lines.

The cytotoxicity of four triterpenoids, euscaphic acid (1), tormentic acid (2), 2alpha-acetyl tormentic acid (3), and 3beta-acetyl tormentic acid (4), isolated from the roots of Cecropia lyratiloba (Moraceae) by countercurrent chromatography, was evaluated in vitro in sensitive and multidrug resistant leukemia cell lines. A structure/activity relationship analysis of the compounds was performed. Acetylation of compound 2 at C2 increased its activity by a factor of 2 while acetylation at C3 had a smaller effect. Compound 1 induces death by activation of caspase-3, dependent apoptotic pathway. Furthermore, the four triterpenoids were also active toward a multidrug resistant (MDR) leukemia cell line, overexpressing glycoprotein-P (P-gp). These results reveal the potential of the terpenoids as source for the development of new anti-neoplastic and anti-MDR drugs.

Activity of Cecropia lyratiloba extract on contractility of cardiac and smooth muscles in Wistar rats.

1. Brazilian forests show high diversity of medicinal plants and several are used in folk medicine for the treatment of hypertension and asthma. The aim of the present study was to investigate the effects of a methanol extract (ME) of Cecropia lyratiloba and its flavonoid fraction (FF) on the contractility of cardiac, vascular and tracheal smooth muscles. 2. Twitches of rat papillary muscles were obtained with electrical stimulation and were recorded before and after exposure to increasing concentrations of ME and FF. 3. Cardiac depression was induced by FF. At 500 microg/mL FF, the amplitude of twitches was reduced to 56.7 +/- 5.1% of control values (P < 0.05). 4. The contractile response to a single concentration of adrenaline (10 micromol/L) was measured before and after exposure to ME and FF in rat aorta rings with intact endothelium. Both ME and FF inhibited adrenaline-induced contractions of the aorta in a concentration-dependent manner. Adrenaline-induced contractions were reduced to 46.4 +/- 9.9 and 34.2 +/- 6.9% (P < 0.05) of control in the presence of 500 microg/mL ME and FF, respectively. 5. The flavonoids isolated from FF, namely isoorientin and a mixture of orientin and isovitexin, were also tested in the aorta. These flavonoid do not seem to be responsible for the vasorelaxant effects of ME and FF. 6. No changes were observed in acetylcholine-precontracted trachea when exposed to ME or FF. 7. Endothelium-dependent vasodilation induced by FF is likely to be mediated by the release of nitric oxide because vascular relaxation was abolished in the presence of N(omega)-nitro-L-arginine methyl ester, an inhibitor of nitric oxide synthase. 8. In conclusion, vascular relaxation induced by ME and FF could explain the traditional use of the extract of C. lyratiloba for treatment of arterial hypertension.