RESUMEN

Schistosomiasis, caused by Schistosoma mansoni Sambon, 1907, is a severe and widely distributed parasitic disease, affecting about 200 million people worldwide. The disease is recognized by elevated mortality rates, especially among those living in areas of poor sanitation. Currently, the chemotherapeutic treatment is solely based on using the praziquantel drug. Therefore, there is a need for the discovery of new medicines for the treatment of this parasitosis. Thus, this work aimed to evaluate the schistosomicidal activity of ethanolic crude extracts from the branches, leaves, flowers, and fruits of Handroanthus impetiginosus (Mart ex DC.) Masttos and characterize its metabolic profile by UPLC-ESI-QTOF analysis. Evaluation of plant extract on S. mansoni was carried out in adult worms in vitro, in which the mortality rate was quantified, and the damages in the tegument of the worms were monitored. All extracts induced changes in the viability of adult males of S. mansoni, causing the death of the parasites, which was directly dependent of the concentration.

Asunto(s)

Bignoniaceae , Esquistosomicidas , Tabebuia , Humanos , Masculino , Esquistosomicidas/farmacología , Esquistosomicidas/uso terapéutico , Frutas , Etanol , Flores , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico

RESUMEN

Piper cubeba is an Asian pepper used in popular medicine for its known antimicrobial, antiparasitic, and anti-inflammatory actions. The study evaluated the effects of dietary inclusion of Piper cubeba ethanolic extract (PE) as a replacement for anantibiotic growth promoter (AGP) on the performance and biochemical serum profile of 1- to 21-d-old broilers (Cobb®). Two hundred one-d-old broilers were housed in experimental battery cages and distributed in a completely randomized design. The following treatments were applied: negative control (NC) - basal diet; positive control (PC) - basal diet with addition of AGP; and the basal diet with inclusion of 0.17%, 0.34%, and 0.52% of PE (NCE1, NCE2, and NCE3, respectively). Growth performance, biochemical serum profile and internal organ weights were evaluated. Birds fed the AGP presented higher feed intake compared with the other treatments (p 0.05). The PC, NC, and NCE1 treatments presented higher weight gain compared with those fed NCE2 and NCE3 (p 0.05). The NC, NCE1, and NCE2 diets promoted better feed conversion ratio than the PC and NCE3 (p 0.05). Lower triglyceride serum levels were determined in broilers fed the NC and NCE1 diets. Amylase serum levels were lower in NCE1 and NCE2 treatments compared with the NC (p 0.05), whereas those obtained with the PC and NCE3 diets were not different (p>0.05) from the others. Organ relative weights were not influenced by the treatments. The inclusion of 0.17% of PE did not compromise the growth performance, biochemical serum profile or organ relative weights of 21-d-old broilers.

Asunto(s)

Animales , Fenómenos Bioquímicos , Piper/química , Suero

RESUMEN

Piper cubeba is an Asian pepper used in popular medicine for its known antimicrobial, antiparasitic, and anti-inflammatory actions. The study evaluated the effects of dietary inclusion of Piper cubeba ethanolic extract (PE) as a replacement for anantibiotic growth promoter (AGP) on the performance and biochemical serum profile of 1- to 21-d-old broilers (Cobb®). Two hundred one-d-old broilers were housed in experimental battery cages and distributed in a completely randomized design. The following treatments were applied: negative control (NC) - basal diet; positive control (PC) - basal diet with addition of AGP; and the basal diet with inclusion of 0.17%, 0.34%, and 0.52% of PE (NCE1, NCE2, and NCE3, respectively). Growth performance, biochemical serum profile and internal organ weights were evaluated. Birds fed the AGP presented higher feed intake compared with the other treatments (p 0.05). The PC, NC, and NCE1 treatments presented higher weight gain compared with those fed NCE2 and NCE3 (p 0.05). The NC, NCE1, and NCE2 diets promoted better feed conversion ratio than the PC and NCE3 (p 0.05). Lower triglyceride serum levels were determined in broilers fed the NC and NCE1 diets. Amylase serum levels were lower in NCE1 and NCE2 treatments compared with the NC (p 0.05), whereas those obtained with the PC and NCE3 diets were not different (p>0.05) from the others. Organ relative weights were not influenced by the treatments. The inclusion of 0.17% of PE did not compromise the growth performance, biochemical serum profile or organ relative weights of 21-d-old broilers.(AU)

Asunto(s)

Animales , Fenómenos Bioquímicos , Suero , Piper/química

RESUMEN

This paper reports on the in vitro antibacterial and in vivo anti-inflammatory properties of a hydroethanolic extract of the aerial parts of Gochnatia pulchra (HEGP). It also describes the antibacterial activity of HEGP fractions and of the isolated compounds genkwanin, scutellarin, apigenin, and 3,5-O-dicaffeoylquinic acid, as evaluated by a broth microdilution method. While HEGP and its fractions did not provide promising results, the isolated compounds exhibited pronounced antibacterial activity. The most sensitive microorganism was Streptococcus pyogenes, with minimum inhibitory concentration (MIC) values of 100, 50 and 25 µg/mL for genkwanin and the flavonoids apigenin and scutellarin, respectively. Genkwanin produced an MIC value of 25 µg/mL against Enterococcus faecalis. A paw edema model in rats and a pleurisy inflammation model in mice aided investigation of the anti-inflammatory effects of HEGP. This study also evaluated the ability of HEGP to modulate carrageenan-induced interleukin-1 beta (IL-1ß), tumor necrosis factor alpha (TNF-α), and monocyte chemoattractant protein-1 (MCP-1) production. Orally administered HEGP (250 and 500 mg/kg) inhibited carrageenan-induced paw edema. Regarding carrageenan-induced pleurisy, HEGP at 50, 100, and 250 mg/kg diminished leukocyte migration by 71.43%, 69.24%, and 73.34% (P<0.05), respectively. HEGP suppressed IL-1ß and MCP-1 production by 55% and 50% at 50 mg/kg (P<0.05) and 60% and 25% at 100 mg/kg (P<0.05), respectively. HEGP abated TNF-α production by macrophages by 6.6%, 33.3%, and 53.3% at 100, 250, and 500 mg/kg (P<0.05), respectively. HEGP probably exerts anti-inflammatory effects by inhibiting production of the pro-inflammatory cytokines TNF-α, IL-1ß, and MCP-1.

Asunto(s)

Antibacterianos/farmacología , Antiinflamatorios/farmacología , Asteraceae/química , Edema/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Extractos Vegetales/farmacología , Animales , Asteraceae/clasificación , Modelos Animales de Enfermedad , Cromatografía de Gases y Espectrometría de Masas , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Ratas , Ratas Wistar

RESUMEN

RESUMO: A atividade antimicobacteriana de diidrocubebina (1), uma lignana dibenzilbutanodioica obtida a partir de extrato etanólico de sementes da Piper cubeba, e seus derivados foram avaliados in vitro contra três diferentes cepas de Mycobacterium utilizando o método de microdiluição. Dentre as lignanas avaliadas 3 e 4 foram as mais ativas, exibindo valores de CIM de 62,5 µg/mL contra M. avium e M. tuberculosis, respectivamente. Os derivados 2-6 obtidos por síntese parcial possuem diferentes substituintes nos carbonos 9 e 9 ', que alteram polaridade, solubilidade e limitam as rotações livres entre C8-C8' em relação de material (1) de partida. As diferenças estruturais entre estes compostos podem fornecer informações importantes sobre a relação estrutura-atividade antimicobacteriana do esqueleto dibenzilbutanodioico, obtido a partir de fonte natural, como um possível alvo para o desenvolvimento de drogas mais potentes contra a tuberculose

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ABSTRACT: Evaluation of antimycobacterial activity of dihydrocubebin lignan extracted from Piper cubeba and its semisynthetic derivatives. The antimycobacterial activity of the dihydrocubebin (1), a dibenzylbutanedioiclignan obtained from ethanolic extract of Piper cubeba seeds, and its derivatives were examined in vitro against three different strains of Mycobacterium using amicrodilution method. Among the lignans evaluated, the 3 and 4 samples were the most active ones, displaying MIC values of 62.5 µg/mL against M. avium and M. tuberculosis, respectively. The derivatives 2-6, obtained for partial synthesis, had different substituents in the carbons 9 and 9', fact thatalters the polarity, solubility and restricts the free rotations between the bonds C8-C8' in relation to the starting material (1). The structural differences among these compounds provide important information about the antimycobacterial structure-activity relationship of the dibenzylbutanodioic skeleton, obtained from natural source, such as a possible target for the development of more powerful drugs against tuberculosis

Asunto(s)

Lignanos/farmacología , Piper/clasificación , Antibacterianos/farmacología , Técnicas In Vitro/instrumentación , Mycobacterium avium/clasificación , Mycobacterium tuberculosis/clasificación

RESUMEN

(±)-Licarin A (1) was obtained by oxidative coupling, and its enantiomers, (-)-licarin A (2) and (+)-licarin A (3), were resolved by chiral HPLC. Schistosomicidal and trypanocidal activities of these compounds were evaluated in vitro against Schistosoma mansoni adult worms and trypomastigote forms of Trypanosoma cruzi. The racemic mixture (1) displayed significant schistosomicidal activity with an LC50 value of 53.57 µM and moderate trypanocidal activity with an IC50 value of 127.17 µM. On the other hand, the (-)-enantiomer (2), displaying a LC50 value of 91.71 µM, was more active against S. mansoni than the (+)-enantiomer (3), which did not show activity. For the trypanocidal assay, enantiomer 2 showed more significant activity (IC50 of 23.46 µM) than enantiomer 3, which showed an IC50 value of 87.73 µM. Therefore, these results suggest that (±)-licarin A (1) and (-)-licarin A (2) are promising compounds that could be used for the development of schistosomicidal and trypanocidal agents.

Asunto(s)

Lignanos/farmacología , Schistosoma mansoni/efectos de los fármacos , Esquistosomicidas/química , Tripanocidas/química , Trypanosoma cruzi/efectos de los fármacos , Animales , Chlorocebus aethiops , Cromatografía Líquida de Alta Presión/métodos , Femenino , Concentración 50 Inhibidora , Lignanos/química , Masculino , Ratones , Ratones Endogámicos BALB C , Estructura Molecular , Acoplamiento Oxidativo , Esquistosomicidas/farmacología , Relación Estructura-Actividad , Tripanocidas/farmacología , Células Vero

RESUMEN

The dibenzylbutyrolactolic lignan (-)-cubebin was isolated from dry seeds of Piper cubeba L. (Piperaceae). (-)-Cubebin possesses anti-inflammatory, analgesic and antimicrobial activities. Doxorubicin (DXR) is a topoisomerase-interactive agent that may induce single- and double-strand breaks, intercalate into the DNA and generate oxygen free radicals. Here, we examine the mutagenicity and recombinogenicity of different concentrations of (-)-cubebin alone or in combination with DXR using standard (ST) and high bioactivation (HB) crosses of the wing Somatic Mutation And Recombination Test in Drosophila melanogaster. The results from both crosses were rather similar. (-)-Cubebin alone did not induce mutation or recombination. At lower concentrations, (-)-cubebin statistically reduced the frequencies of DXR-induced mutant spots. At higher concentrations, however, (-)-cubebin was found to potentiate the effects of DXR, leading to either an increase in the production of mutant spots or a reduction, due to toxicity. These results suggest that depending on the concentration, (-)-cubebin may interact with the enzymatic system that catalyzes the metabolic detoxification of DXR, inhibiting the activity of mitochondrial complex I and thereby scavenging free radicals. Recombination was found to be the major effect of the treatments with DXR alone. The combined treatments reduced DXR mutagenicity but did not affect DXR recombinogenicity.

Asunto(s)

Antimutagênicos/farmacología , Doxorrubicina/toxicidad , Furanos/farmacología , Lignanos/farmacología , Mutágenos/toxicidad , Recombinación Genética/efectos de los fármacos , Alas de Animales/efectos de los fármacos , Animales , Drosophila melanogaster/genética , Interacciones Farmacológicas , Femenino , Larva/efectos de los fármacos , Masculino , Pruebas de Mutagenicidad , Piper/química , Extractos Vegetales/farmacología , Alas de Animales/citología

RESUMEN

Baccharis dracunculifolia (Asteraceae), the most important plant source of the Brazilian green propolis (GPE), displayed in vitro activity against Leishmania donovani, with an IC(50) value of 45 microg/mL, while GPE presented an IC(50) value of 49 microg/mL. Among the isolated compounds of B. dracunculifolia, ursolic acid, and hautriwaic acid lactone showed IC(50) values of 3.7 microg/mL and 7.0 microg/mL, respectively. Uvaol, acacetin, and ermanin displayed moderate antileishmanial activity. Regarding the antiplasmodial assay against Plasmodium falciparum, BdE and GPE gave similar IC(50) values (about 20 microg/mL), while Hautriwaic acid lactone led to an IC(50) value of 0.8 microg/mL (D6 clone).

Asunto(s)

Antimaláricos/farmacología , Baccharis/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Triterpenos/farmacología , Tripanocidas/farmacología , Animales , Antimaláricos/efectos adversos , Antimaláricos/aislamiento & purificación , Chlorocebus aethiops , Leishmania donovani/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pruebas de Sensibilidad Parasitaria , Fenoles/efectos adversos , Fenoles/aislamiento & purificación , Extractos Vegetales/efectos adversos , Extractos Vegetales/química , Hojas de la Planta , Plasmodium falciparum/efectos de los fármacos , Própolis , Triterpenos/efectos adversos , Triterpenos/aislamiento & purificación , Tripanocidas/efectos adversos , Tripanocidas/aislamiento & purificación , Células Vero

RESUMEN

Leandra lacunosa, popularly known as "erva-do-jabuti", is used in Brazilian folkloric medicine for the treatment of diabetes mellitus. Based on this traditional indication, the aim of this work was to evaluate the hypoglycemic activity of the hydroalcoholic extract of L. lacunosa aerial parts (LLH) in normal and alloxan-induced diabetic rats. Chromatographic fractionation of LLH was also carried out by several techniques, affording isolation of the following major compounds: ursolic acid (1), kaempferol (2), luteolin (3), and quercetin (4). The oral administration of LLH (500 mg/kg) in normal rats caused a significant reduction of 24.7% (P<0.05) in the blood glucose levels after 2 h of treatment, while the administration of chlorpropamide (20 mg/kg, p.o.) led to a reduction of 40.2% (P<0.01). After oral administration of glucose (10 g/kg, p.o.), LLH (500 mg/kg, p.o.) significantly inhibited the increase in blood glucose levels compared with the negative control group. The oral treatment with LLH (500 mg/kg) in alloxan-induced diabetic rats significantly reduced the blood glucose levels in 47.8% after 4 h of treatment, while chlorpropamide resulted in a significant reduction of 71.7% in the 4th hour. Our results showed that LLH, displays hypoglycemic activity, which may be related to the effect of the major compounds identified in the crude extract. This study seems to provide biological evidence for the folkloric use of L. lacunosa in the treatment of diabetes mellitus.

Asunto(s)

Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Melastomataceae/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Aloxano , Animales , Glucemia/efectos de los fármacos , Prueba de Tolerancia a la Glucosa , Hipoglucemiantes/química , Masculino , Estructura Molecular , Ratas , Ratas Wistar

RESUMEN

The trypanocidal activity of racemic mixtures of cis- and trans-methylpluviatolides was evaluated in vitro against trypomastigote forms of two strains of Trypanosoma cruzi, and in the enzymatic assay of T. cruzi gGAPDH. The cytotoxicity of the compounds was assessed by the MTT method using LLC-MK2 cells. The effect of the compounds on peroxide and NO production were also investigated. The mixture of the trans stereoisomers displayed trypanocidal activity (IC50 approximately 89.3 microM). Therefore, it was separated by chiral HPLC, furnishing the (+) and (-)-enantiomers. Only the (-)-enantiomer was active against the parasite (IC50 approximately 18.7 microM). Despite being inactive, the (+)-enantiomer acted as an antagonistic competitor. Trans-methylpluviatolide displayed low toxicity for LLC-MK2 cells, with an IC50 of 6.53 mM. Furthermore, methylpluviatolide neither inhibited gGAPDH activity nor hindered peroxide and NO production at the evaluated concentrations.

Asunto(s)

Lactonas/química , Lactonas/farmacología , Lignanos/química , Lignanos/farmacología , Tripanocidas/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Línea Celular , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Relación Estructura-Actividad

RESUMEN

The activities of the crude ethanol extract from Piper cubeba seeds, (-)-cubebin and its semi-synthetic derivatives were evaluated against oral pathogens. The crude ethanol extract was more active against Streptococcus salivarius (MIC value of 80 microg/mL). (-)-Cubebin displayed MIC values ranging from 0.20 mm for Streptococcus mitis to 0.35 mm for Enterococcus faecalis. The natural product (-)-cubebin and its semi-synthetic derivative (-)-hinokinin displayed bacteriostatic activity at all evaluated concentrations, as well as fungicidal activity against Candida albicans at 0.28 mm. The O-benzyl cubebin derivative showed fungistatic and fungicidal effects against C. albicans at 0.28 mm and 0.35 mm, respectively. Also, the other dibenzylbutyrolactone derivatives [(-)-6,6'-dinitrohinokinin and (-)-O-(N,N-dimethylaminoethyl)-cubebin] displayed bacteriostatic and fungistatic effects at the evaluated concentrations. Moreover, the semi-synthetic derivative (-)-6,6'-dinitrohinokinin was the most active compound against all the evaluated microorganisms. Therefore, it may be suggested that the presence of the carbonyl group at C-9 plus the introduction of polar groups in the aromatic rings improve the antimicrobial activity of dibenzylbutyrolactone compounds.

Asunto(s)

Antiinfecciosos/farmacología , Candida albicans/efectos de los fármacos , Enterococcus faecalis/efectos de los fármacos , Lignanos/farmacología , Piper/química , Streptococcus/efectos de los fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/farmacología , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Benzodioxoles , Dioxoles/química , Dioxoles/farmacología , Lignanos/química , Lignanos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología

RESUMEN

The anti-inflammatory and antinociceptive effects of the crude hydroalcoholic extract (PE) of Pfaffia glomerata roots was assessed in the carrageenan-induced rat paw edema at the doses of 100, 200 and 300 mg/kg, using different animal models. An anti-inflammatory dose effect response correlation of r=0.997 and Y=11.67x+0.02 was found. At the same doses, the extract-inhibited acetic acid-induced writhing in mice, but no dose response correlation was found. Oral administration of 100 mg/kg of PE and 0.5 mg/kg of dexamethazone inhibited by 29 and 61%, the granulomatous tissue formation (p>0.05), respectively. These results indicate the potential of this plant extract to treat chronic inflammation. At the assayed doses no significant activity was found in the hot plate test, as well as in the cell migration-induced by carrageenan.

Asunto(s)

Amaranthaceae , Analgésicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Raíces de Plantas/química , Analgésicos/química , Animales , Antiinflamatorios/química , Carragenina , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Edema/tratamiento farmacológico , Masculino , Ratones , Dimensión del Dolor , Fitoterapia , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar

RESUMEN

The anti-inflammatory and antinociceptive effects of the benzylated cubebin derivative, obtained by reaction of (-)-cubebin with benzyl bromide, were investigated using different animal models. The (-)-o-benzyl cubebin showed a low anti-inflammatory effect (16.2%) in relation to cubebin (57%) and indomethacin (77%) in the carrageenin-induced paw edema in rats, but on the other hand it was more effective (80%) than (-)-cubebin (41%) in inhibiting acetic acid-induced writhing in mice, producing dose-response correlation with doses of 10, 20 and 40 mg/kg, respectively. Moreover, this derivative compound did not show activity in both the hot plate and the cell migration test in rats. Overall, the results showed that the benzylation of cubebin were efficient in enhancing only its analgesic activity.

Asunto(s)

Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/farmacología , Dioxoles/síntesis química , Dioxoles/farmacología , Furanos/síntesis química , Furanos/farmacología , Acetatos , Animales , Carragenina , Edema/inducido químicamente , Edema/prevención & control , Indicadores y Reactivos , Masculino , Dimensión del Dolor/efectos de los fármacos , Piper/química , Ratas , Ratas Wistar , Tiempo de Reacción/efectos de los fármacos

RESUMEN

The anti-inflammatory and antinociceptive effects of the acetylated (2), methylated (3) and aminated (4) derivatives of cubebin (1), obtained by its reaction with acetic anhydride, methyl iodide and dimethylethylamine chloride, respectively, were investigated, using different animal models. The compound (2) was the most effective anti-inflammatory one in the carrageenin-induced paw edema in rats and was the only one which showed dose-response correlation for this assay with r = 0.993 and Y = 64.58x + 0.22. Besides, compounds (2) and (4) were more effective than cubebin in inhibiting acetic acid-induced writhing in mice, producing dose-response correlation with doses of 10, 20 and 30 mg/kg, respectively. Regarding the hot plate and the cell migration tests in rats, none of the four tested compounds showed activity. Overall, the results showed that the acetylation and amination of cubebin were efficient in enhancing its analgesic activity, as well as its anti-inflammatory activity.

Asunto(s)

Analgésicos , Antiinflamatorios no Esteroideos/farmacología , Dioxoles/farmacología , Furanos/farmacología , Lignanos/química , Ácido Acético/efectos adversos , Ácido Acético/antagonistas & inhibidores , Animales , Antiinflamatorios no Esteroideos/síntesis química , Carragenina/efectos adversos , Carragenina/antagonistas & inhibidores , Dioxoles/síntesis química , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Furanos/síntesis química , Lignanos/síntesis química , Lignanos/farmacología , Masculino , Ratones , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Dimensión del Dolor/efectos de los fármacos , Ratas , Ratas Wistar

RESUMEN

Three different concentrations (1, 10 and 50 microg/ml) of lyophilized hydroalcoholic crude extract of Pfaffia glomerata roots were assayed in vitro against strains of Trypanosoma cruzi (Y) and Leishmania braziliensis. It was observed that P. glomerata hydroalcoholic extract was relatively active within the tested concentrations for L. (V) braziliensis, but inactive against T. cruzi. Despite the fact that both protozoans belong to the Trypanosomatidae family, we suggest that the difference observed for activity should be related to the biological differences between the two parasite species.

Asunto(s)

Amaranthaceae/química , Antiprotozoarios/farmacología , Leishmania braziliensis/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiprotozoarios/química , Relación Dosis-Respuesta a Droga , Ratones , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Tripanocidas/farmacología

RESUMEN

The analgesic effects of the hexane, methylene chloride and ethanol extracts of Miconia rubiginosa were evaluated in mice and rats using the acetic acid-induced writhing and hot plate tests. The extracts (100, 200 and 300 mg/kg body wt.) and indomethacin (5 mg/kg body wt.) produced a significant (p < 0.05 and p < 0.01) inhibition of acetic acid-induced abdominal writhing. These same extracts (200 mg/kg body wt.) showed a significant (p < 0.05) antinociceptive effect, lower than that produced by morphine (4 mg/kg body wt.). The fractionation of the methylene chloride extract yielded ursolic and oleanoic acids as the major compounds. Using only gas chromatography, it was possible to identify the following triterpenes in the hexane extract: alpha-amyrin, beta-amyrin, lupeol and beta-sitosterol.

Asunto(s)

Analgésicos/farmacología , Melastomataceae , Dolor/prevención & control , Fitoterapia , Extractos Vegetales/farmacología , Ácido Acético , Analgésicos/administración & dosificación , Analgésicos/uso terapéutico , Animales , Relación Dosis-Respuesta a Droga , Calor , Masculino , Ratones , Dolor/inducido químicamente , Dimensión del Dolor/efectos de los fármacos , Componentes Aéreos de las Plantas , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Ratas

RESUMEN

This work reports the results of the in vitro assay against extracellular forms of Leishmania (viannia) braziliensis of eleven dibenzylbutyrolactone derivatives, either isolated from plants or obtained by synthesis. From these, only two showed relative biological activity against the parasite, the raceme mixtures of methylpluviatolide: IC50 = 496 mM and (-)-6,6'- dinitrocubebin: IC50 = 510,4 μM. Thus, it can be suggested that the metabolic pathway responsible for the biological activity of these compounds against this parasite genera differs from the one related to Trypanosoma cruzi, for which these compounds were quite active. This fact highly also suggests that this class of compounds is more selective against T. cruzi. Nevertheles, other lignans derivatives should be obtained to allow the fully evaluation of this class of lignans against Leishmaniosis.

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Este trabalho apresenta os resultados de ensaios in vitro contra formas extracelulares de Leishmania (viannia) braziliensis de onze derivados de dibenzilbutirolactonas isolados de plantas ou obtidos através de síntese. Destes, só dois mostraram atividade biológica relativa contra o parasita, as misturas racêmicas de methilpluviatolide,: IC50 = 496 M e (-) -6,6' - dinitrocubebin: IC50 = 510,4 M. Assim, pode-se sugerir que o caminho metabólico responsável para a atividade biológica destas combinações contra estes gêneros de parasita difere do relacionado a Trypanosoma cruzi para o qual estas combinações foram bastante ativas. Este fato também sugere fortemente que essa classe de combinações é mais seletivo contra T. cruzi. Dessa forma, deveriam ser obtidos outros derivados de lignanas para permitir a completa avaliação desta classe de substâncias contra Leishmaniose.

Asunto(s)

Extractos Vegetales , Caries Dental , Stryphnodendron barbatimam