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1.
Neurogastroenterol Motil ; 34(2): e14277, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34662472

RESUMO

BACKGROUND: This study investigated the antidiarrheal potential of the aqueous extract (AECR) and hydroalcoholic extract of Campomanesia reitziana leaves (HECR), its ethyl acetate (EAF) and dichloromethane fractions (DCMF), and myricitrin isolated from EAF. METHODS: The total phenols and flavonoids were measured, followed by chromatography and myricitrin isolation. The 2,2-diphenyl-1-picryl-hydrazyl scavenger activity, the cytotoxicity, and the effects on LPS-induced nitrite production in intestinal epithelial cells (IEC-6) were quantified. The effect of HECR, EAF, DCMF, and AECR on intestinal motility (IT), gastric emptying (GE), and castor oil-induced diarrhea in mice was determined, as well as its antimicrobial activity. KEY RESULTS: The administration of AECR 10% (10 ml/kg, p.o), but not HECR (300 mg/kg), reduced the GE and IT by 52 and 51%. The EAF and DCMF at 300 mg/kg also reduced IT but did not change GE. Moreover, AECR and EAF, but not DCMF, inhibited the castor oil-induced diarrhea and naloxone or metoclopramide pretreatment did not change these effects. Myricitrin did not change IT and the evacuation index of mice. Finally, the dry residue of AECR inhibited bacterial growth and EAF showed bacteriostatic activity against S. aureus, E. coli, and S. typhimurium and antifungal for C. albicans. However, none of the preparations alter the viability of Giardia spp. trophozoites. CONCLUSIONS: The AECR and EAF can be effective to treat diarrhea acting through opioid- or dopaminergic type 2 receptor-independent mechanisms and by its antimicrobial actions.


Assuntos
Anti-Infecciosos , Óleo de Rícino , Analgésicos Opioides/efeitos adversos , Animais , Anti-Infecciosos/efeitos adversos , Antidiarreicos/farmacologia , Antidiarreicos/uso terapêutico , Óleo de Rícino/toxicidade , Diarreia/induzido quimicamente , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Escherichia coli , Motilidade Gastrointestinal , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Staphylococcus aureus
2.
Molecules ; 26(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063814

RESUMO

In addition to the trichilianones A-D recently reported from Trichilia adolfi, a continuing investigation of the chemical constituents of the ethanol extract of the bark of this medicinal plant yielded the five new limonoids 1-5. They are characterized by having four fused rings and are new examples of prieurianin-type limonoids, having a ε-lactone which in 4 and 5 is α, ß- unsaturated. The structures of the isolated metabolites were determined by high field NMR spectroscopy and HR mass spectrometry. The new metabolites were shown to have the ε-lactone fused with a tetrahydrofuran ring which is connected to an oxidized hexane ring joined with a cyclo-pentanone having a 3-furanyl substituent. As the crude extract possesses antileishmanial activity, the compounds were assayed for cytotoxic and antiparasitic activities in vitro in murine macrophage cells (raw 264.7 cells) and in Leishmania amazoniensis as well as L. braziliensis promastigotes. Metabolites 1-3 and 5 showed moderate cytotoxicity (between 30-94 µg/mL) but are not responsible for the antileishmanial effect of the extract.


Assuntos
Limoninas/isolamento & purificação , Meliaceae/química , Pregnanos/isolamento & purificação , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Sobrevivência Celular/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Limoninas/química , Limoninas/farmacologia , Espectrometria de Massas/métodos , Camundongos , Estrutura Molecular , Pregnanos/química , Pregnanos/farmacologia , Espectroscopia de Prótons por Ressonância Magnética/métodos , Células RAW 264.7
3.
Nat Prod Res ; 35(22): 4876-4880, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32174188

RESUMO

Parasitoses are very common throughout the world, generating serious consequences for public health. Leishmaniosis and giardiasis are examples of fairly recurrent, but neglected diseases. Several higher plants have demonstrated promising activity against the parasites. The aim of this study was to evaluate the biological activity of extracts, fractions and isolated compounds from the leaves and stems of two Brazilian plants: Eugenia mattosii and Marlierea eugeniopsoides (Myrtaceae) against Leishmania and Giardia. XTT and the fluorimetric method were used to for this evaluation, respectively. Cytotoxicity was evaluated against HeLa cells. The results demonstrated that chloroform fractions of E. matosii and pinostrobin presented the most pronounced antiparasitic activity, with the CLF-stems being the most effective against Leishmania amazonensis and Leishmania braziliensis. Pinostrobin also presented activity against G. lamblia. Therefore, E. mattosii stems and pinostrobin may be considered possible targets for the continuity of studies against other parasites.


Assuntos
Antiprotozoários , Eugenia , Leishmania , Myrtaceae , Antiparasitários/farmacologia , Células HeLa , Humanos , Extratos Vegetais/farmacologia
4.
Food Res Int ; 137: 109382, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233084

RESUMO

The Balanophoraceae Ombrophytum subterraneum is an endemic highland food plant occurring in Bolivia, northern Argentina and Chile. The upper part of this parasitic plant is eaten fresh. The aim of this work was to characterize the compounds occurring in the edible part and to assess any differences between the inflorescence and tuber. Ethanol extracts of the different plant parts were analyzed for antioxidant activity by the ORAC, TEAC, FRAP, CUPRAC and DPPH methods as well as for the effect on enzymes related to metabolic syndrome (α-amylase, α-glucosidase and pancreatic lipase). The main constituents were isolated by a combination of gel permeation in Sephadex LH-20 and countercurrent chromatography (CCC). Five compounds were isolated and fully identified by spectroscopic and spectrometric means. The new 3',5,5',7-tetrahydroxyflavanone 7-O-ß-D-1 â†’ 6 diglucoside was isolated for the first time. HPLC-ESI-MS/MS analysis allowed the identification of 19 compounds, including flavanones, flavanols, flavonols, dehydroflavonols and lignans, mainly as glycosides. A strong inhibition towards α-glucosidase was observed for the edible parts (IC50: 1.46 µg/mL) as well as for the tuber and inflorescence (IC50: 1.56 µg/mL and 0.87 µg/mL, respectively). A significant correlation was established between the total phenolic and the antioxidant capacity of the extracts as well as with the content of the new flavanone diglucoside. This is the first comprehensive report on the naturally occurring antioxidants and enzyme inhibitors from this native highland food resource.


Assuntos
Antioxidantes , Balanophoraceae , Antioxidantes/análise , Argentina , Bolívia , Chile , Extratos Vegetais/farmacologia , Plantas Comestíveis , Espectrometria de Massas em Tandem , alfa-Glucosidases
5.
Con-ciencia (La Paz) ; 8(1): 21-31, 20200400.
Artigo em Espanhol | LILACS, LIBOCS | ID: biblio-1178427

RESUMO

INTRODUCCIÓN: la presencia de compuestos activos en las plantas las posiciona como una fuente alternativa para el descubrimiento de nuevos fármacos. OBJETIVO: realizar la bioprospección de plantas utilizadas en la medicina tradicional tacana frente a cultivos de Plasmodium falciparum. MÉTODOS: se obtuvieron extractos por maceración en etanol a temperatura ambiente, de 31 órganos colectados de 23 plantas, estos fueron evaluados sobre cultivos asincrónicos de la cepa de Plasmodium falciparum resistente a la Cloroquina (FCR3). A los extractos que mostraron actividad antiplasmódica (CI50<20µg/mL), se evaluó la citotoxicidad (DL50) frente a células HeLa y se calculó el índice de selectividad (IS=DL50/CI50). Los extractos que dieron resultados IS>5, fueron seleccionados como promisorios. RESULTADOS: se obtuvieron 3 plantas muy activas (CI50<10µg/mL); 2 moderadamente activas (10µg/mL20µg/mL). De las 9 plantas que presentaron actividad, solo 2 plantas presentaron IS>5. CONCLUSIONES: incorporar los conocimientos del uso tradicional para realizar las evaluaciones biológicas es de mucha ayuda en la selección de plantas con efectos antiplasmódicos.


INTRODUCTION: the presence of active compounds in plants, converts them as an alternative to find new drugs. OBJECTIVE: carry out the bioprospecting of plants used in Tacana traditional medicine against Plasmodium falciparum cultures. METHODS: from the 31 collected organs of 23 plants, raw extracts were obtained by ethanolic maceration at room temperature and these were evaluated on asynchronic cultures of the strain Plasmodium falciparum resistant to Chloroquine (FCR3). The active extracts (IC50<20µg/mL), were evaluated for cytotoxicity (LD50) against HeLa cells and the Selectivity Index (IS=DL50/IC50) was calculated. The extracts that sowed IS>5were selected as promising. RESULTS: a total of 3 species were very active (IC50<10µg/mL); 2 were moderately active (10µg/mL20µg/mL). From the 9 active plants only 2 presented IS>5. CONCLUSIONS: incorporating the traditional knowledge to carry out biological evaluations is very helpful in the selection of plants with antiplasmodial effects.


Assuntos
Plantas , Plasmodium falciparum , Cloroquina , Medicina Tradicional , Técnicas In Vitro , Preparações Farmacêuticas
6.
Con-ciencia (La Paz) ; 7(2): 29-38, nov. 2019. ilus., tab.
Artigo em Espanhol | LILACS, LIBOCS | ID: biblio-1178625

RESUMO

La tripanosomiasis americana es una enfermedad infecciosa desatendida, causada por el parásito protozoo Trypanosoma cruzi, que no cuenta con tratamiento en la fase crónica de esta enfermedad mortal, uno de los desafíos es encontrar terapias efectivas para esta compleja enfermedad, dado que no presenta síntomas asociables a la parasitosis por lo que es desconocida entre los médicos tradicionales. Nuestra Facultad está evaluando la medicina tradicional tacana como fuente de agentes antiparasitarios potenciales. El objetivo de este trabajo fue identificar productos naturales trypanocidas utilizando el método colorimétrico XTT-PMS. Para ello, se realizaron curvas de crecimiento de epimastigotes de T. cruzi y determinamos el tiempo óptimo de realización de los ensayos. Se seleccionó la población inicial de trabajo (3x106 parásitos/mL), las condiciones de incubación (medio LIT, 27ºC, 72 horas) y revelado (XTT-PMS, 4 horas). Con el protocolo optimizado, se realizaron evaluaciones de actividad de drogas control, controles naturales y 20 extractos crudos de plantas medicinales de la amazonía. La actividad se basó en cálculos de concentración inhibitoria media y se consideraron activos las sustancias con CI50<50µg/mL. De los 20 extractos evaluados, el 40% fueron activos. Las plantas más interesantes fueron Sipu sipu (CI50=8.9±1.7µg/mL), Ejije bid'u (CI50=9.1±1.5µg/mL) e Id'ene eidhue (CI50=10.8±1.1µg/mL) con valores de CI50 cercanos a los controles, confirmando la utilidad y potencial del protocolo desarrollado


American trypanosomiasis is listed among the unattended infectious disease, is caused by the protozoan parasite Trypanosoma cruzi, and has no treatment in the chronic phase of this deadly disease. One of the challenges is finding effective therapies for this complex disease, given that it does not present any associated symptoms to the parasitism and is unknown among traditional doctors. Our Faculty is evaluating tacana traditional medicine as a source of potential antiparasitic agents. The objective of this work was to identify trypanocidal natural products using the XTTPMS colorimetric method. For this, growth curves of T. cruzi epimastigotes were made to determine the optimal time to carry out the tests. The initial work population (3x106 parasites/mL), the incubation conditions (medium LIT, 27ºC, 72 hours) and revealed process (XTT-PMS, 4 hours) were selected. With the optimized protocol, activity evaluations of control drugs, natural controls and 20 crude extracts of medicinal plants of the Amazon were carried out. The activity was based on calculations of mean inhibitory concentration and substances with IC50 <50µg/mL were considered active. Of the 20 extracts evaluated, 40% were active. The most interesting plants were Sipu sipu (IC50=8.9±1.7µg/mL), Ejije bid'u (IC50=9.1±1.5µg/mL) and Id'ene eidhue (IC50=10.8±1.1µg/mL) with values of IC50 close to the controls, confirming the usefulness and potential of the developed protocol.


Assuntos
Plantas Medicinais , Concentração Inibidora 50 , Medicina Tradicional , Terapêutica , Trypanosoma cruzi , Preparações Farmacêuticas
7.
J Ethnopharmacol ; 216: 120-133, 2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29391199

RESUMO

ETNOPHARMACOLOGICAL RELEVANCE: Thirty-eight Tacana medicinal plant species used to treat skin problems, including leishmania ulcers, skin infections, inflammation and wound healing, were collected in the community of Buena Vista, Bolivia, with the Tacana people. Twenty two species are documented for the first time as medicinal plants for this ethnic group living in the northern area of the Department of La Paz. AIM OF THE STUDY: To evaluate the leishmanicidal effect (IC50) and cytotoxicity (LD50) of the selected plants. To carry out bioguided studies on the active extracts. To assess the potential of Bolivian plant biodiversity associated with traditional knowledge in the discovery of alternative sources to fight leishmaniasis. MATERIALS AND METHODS: Seventy three ethanol extracts were prepared from 38 species by maceration and were evaluated in vitro against promastigotes of Leishmania amazonensis and L. braziliensis. Active extracts (IC50 ≤ 50 µg/mL) were fractionated by chromatography on Silica gel column and the fractions were assessed against the two Leishmania strains. The most active fractions and the crude extracts were evaluated against reference strains of L. amazonensis, L. braziliensis, L. aethiopica, two native strains (L. Lainsoni and L. braziliensis) and for cytotoxicity against HeLa cells. The chromatographic profile of the active fractions was obtained by reverse phase chromatography using HPLC. RESULTS: From the 73 extracts, 39 extracts (53.4%) were inactive and 34 showed activity. Thirteen species were sselected for bioguided studies. The crude extracts and their 36 fractions were evaluated against two Leishmania strains. The most active fraction were tested in a panel of five leishmania strains and for cytotoxicity. The Selective Index (SI = LD50/IC50) was calculated, and were generally low. Retention time and UV spectra were recorded for the active fractions by HPLC-DAD using a reverse phase column. Profiles were very different from each other, showing the presence of different compounds. CONCLUSION: Bolivian traditional knowledge from the Tacanba was useful to identify plants with effect on Leishmania promastigotes. Chromatographic bioguided studies showed stronger leishmanicidal and cytotoxic activity for the medium polar fraction. HPLC analysis showed different chromatographic profiles of the active fractions.


Assuntos
Leishmania braziliensis/efeitos dos fármacos , Medicina Tradicional , Extratos Vegetais/farmacologia , Plantas Medicinais , Tripanossomicidas/farmacologia , Bolívia , Sobrevivência Celular/efeitos dos fármacos , Etanol/química , Células HeLa , Humanos , Leishmania braziliensis/crescimento & desenvolvimento , Dose Letal Mediana , Testes de Sensibilidade Parasitária , Fitoterapia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Plantas Medicinais/química , Plantas Medicinais/classificação , Plantas Medicinais/toxicidade , Solventes , Tripanossomicidas/isolamento & purificação , Tripanossomicidas/toxicidade
8.
Phytomedicine ; 25: 61-70, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28190472

RESUMO

BACKGROUND: We previously described the gastroprotective effect of 2-phenylquinoline (2-PQ), the main alkaloid isolated from the bark of Galipea longiflora (Rutaceae). However, despite the significant and promising results, the pharmacological mechanisms of the gastroprotection induced by 2-PQ have not been investigated. PURPOSE: To evaluate the mechanisms underlying the gastroprotective effects of 2-PQ. STUDY DESIGN: We used an in vivo mouse ulcer model and in vitro methodologies involving H⁺/K⁺-ATPase and L929 murine fibroblasts. METHODS: The gastroprotective activity of 2-PQ (10-100 mg/kg, orally, p.o) was assessed against gastric ulcer induced by 60% ethanol/0.03 M hydrochloric acid (HCl) in mice or that induced by indomethacin (80 mg/kg, p.o) in rats. The cytotoxicity was assessed in L929 murine fibroblasts. Ulcerated tissues were analyzed histologically, histochemically, and biochemically. The antisecretory activity of 2-PQ was evaluated in vivo and in vitro. RESULTS: 2-PQ showed no cytotoxicity, reduced the lesion area induced by ethanol/HCl (log half-maximal effective dose, ED50 = 1.507), and the histological evaluation supported these results. Furthermore, 2-PQ reduced indomethacin-induced gastric ulceration. The gastroprotection was accompanied by normalization of superoxide dismutase (SOD) and glutathione-S-transferase (GST) activity, an intense increase in reduced glutathione (GSH) levels, and reduction in lipid peroxide (LPO) and tumor necrosis factor (TNF)-α levels in the gastric mucosa. The antisecretory properties of 2-PQ were confirmed by the decreased volume and total acidity of the gastric juice, and it reduced histamine- or pentagastrin-stimulated gastric acid secretion. However, 2-PQ did not change the in vitro H⁺/K⁺-ATPase activity or the content of gastric-adhered mucous in mice. In addition, pretreatment with N-ethylmaleimide, NG-nitro-l-arginine methyl esters, yohimbine, or indomethacin reversed the gastroprotective effect of 2-PQ, suggesting nitric oxide, nonprotein sulfhydryl compounds, α-2-receptors, and prostaglandin were involved. CONCLUSION: 2-PQ provides gastroprotection by reducing oxidative damage and inhibiting acid secretion mediated by histaminergic and gastrinergic regulatory pathways.


Assuntos
Alcaloides/farmacologia , Antiulcerosos/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quinolinas/farmacologia , Rutaceae/química , Úlcera Gástrica/metabolismo , Alcaloides/isolamento & purificação , Alcaloides/uso terapêutico , Animais , Antiulcerosos/isolamento & purificação , Antiulcerosos/uso terapêutico , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Etanol/efeitos adversos , Ácido Gástrico/metabolismo , Suco Gástrico/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Glutationa/metabolismo , Glutationa Transferase/metabolismo , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Ácido Clorídrico , Indometacina , Masculino , Camundongos , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Quinolinas/isolamento & purificação , Quinolinas/uso terapêutico , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
J Nat Prod ; 79(1): 98-105, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26689830

RESUMO

Purification of a diethyl ether extract of the Argentinian fern Elaphoglossum lindbergii afforded five new prenylated acylphloroglucinols, lindbergins E-I (1-5), of which two showed significant in vitro leishmanicidal activity against promastigotes of Leishmania braziliensis and L. amazonensis. The structures of compounds 1-5 were elucidated based on analysis of their spectroscopic data and comparison with values previously reported for other phloroglucinol derivatives isolated from plant species of the genera Hypericum, Dryopteris, and Elaphoglossum. Fragmentation and rearrangement patterns of prenylated acylphloroglucinols were analyzed, and some mechanisms were proposed to rationalize the peaks observed in the mass spectra of these natural products produced by EI and FAB. Compounds isolated from E. lindbergii show the opposite absolute configuration when compared to those reported from E. crassipes. Empirical evidence indicates that acylphloroglucinols carrying a prenylated acylfilicinic acid residue possess a high-amplitude configuration-dependent Cotton effect centered at 350-360 nm in their CD curves, from which the absolute configuration of the sole chiral center of the prenylated acylfilicinic acid moiety can be deduced.


Assuntos
Gleiquênias/química , Leishmania/efeitos dos fármacos , Floroglucinol/isolamento & purificação , Floroglucinol/farmacologia , Hypericum/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Floroglucinol/química , Prenilação
10.
Artigo em Inglês | MEDLINE | ID: mdl-23840252

RESUMO

This study evaluated extracts, fractions, and isolated compounds from some selected Brazilian medicinal plants against strains of promastigotes of Leishmania amazonensis and L. brasiliensis in vitro. The cell viability was determined, comparing the results with reference standards. The dichloromethane fractions of the roots, stems, and leaves of Allamanda schottii showed IC50 values between 14.0 and 2.0 µ g/mL. Plumericin was the main active compound, with IC50 of 0.3 and 0.04 µ g/mL against the two species of Leishmania analyzed. The hexane extract of Eugenia umbelliflora fruits showed IC50 of 14.3 and 5.7 µ g/mL against L. amazonensis and L. brasiliensis, respectively. The methanolic extracts of the seeds of Garcinia achachairu and guttiferone A presented IC50 values of 35.9 and 10.4 µ g/mL, against L. amazonensis, respectively. The ethanolic extracts of the stem barks of Rapanea ferruginea and the isolated compound, myrsinoic acid B, presented activity against L. brasiliensis with IC50 of 24.1 and 6.1 µ g/mL. Chloroform fraction of Solanum sisymbriifolium exhibited IC50 of 33.8 and 20.5 µ g/mL, and cilistol A was the main active principle, with IC50 of 6.6 and 3.1 µ g/mL against L. amazonensis and L. brasiliensis, respectively. It is concluded that the analyzed plants are promising as new and effective antiparasitic agents.

11.
Mem Inst Oswaldo Cruz ; 108(2): 140-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23579790

RESUMO

This paper evaluates CHCl3 and CH3OH extracts of the stem bark, branches and leaves of Drimys brasiliensis and drimane sesquiterpenes isolated from the stem bark against strains of Leishmania amazonensis and Leishmania braziliensis promastigotes and Plasmodium falciparum trophozoites. All of the extracts and compounds were tested in cell lines in comparison with reference standards and cell viability was determined by the XTT method. The CHCl3 and CH3OH extracts from the stem bark and branches yielded promising results against two strains of Leishmania, with 50% inhibitory concentrations (IC50 ) values ranging from 39-100 µg/mL. The CHCl3 extract of the stem bark returned IC50 values of 39 and 40.6 µg/mL for L. amazonensis and L. braziliensis, respectively. The drimanes were relatively effective: 1-ß-(p-coumaroyloxy)-polygodial produced IC50 values of 5.55 and 2.52 µM for L. amazonensis and L. braziliensis, respectively, compared with 1-ß-(p-methoxycinnamoyl)-polygodial, which produced respective IC50 values of 15.85 and 17.80 µM. The CHCl3 extract demonstrated activity (IC50 of 3.0 µg/mL) against P. falciparum. The IC50 values of 1-ß-(p-cumaroyloxyl)-polygodial and 1-ß-(p-methoxycinnamoyl)-polygodial were 1.01 and 4.87 µM, respectively, for the trophozoite strain. Therefore, the results suggest that D. brasiliensis is a promising plant from which to obtain new and effective antiparasitic agents.


Assuntos
Antiprotozoários/farmacologia , Drimys/química , Leishmania braziliensis/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos/farmacologia , Antimaláricos/farmacologia , Concentração Inibidora 50 , Testes de Sensibilidade Parasitária , Sesquiterpenos Policíclicos
12.
Mem. Inst. Oswaldo Cruz ; 108(2): 140-144, abr. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-670397

RESUMO

This paper evaluates CHCl3 and CH3OH extracts of the stem bark, branches and leaves of Drimys brasiliensis and drimane sesquiterpenes isolated from the stem bark against strains of Leishmania amazonensis and Leishmania braziliensis promastigotes and Plasmodium falciparum trophozoites. All of the extracts and compounds were tested in cell lines in comparison with reference standards and cell viability was determined by the XTT method. The CHCl3 and CH3OH extracts from the stem bark and branches yielded promising results against two strains of Leishmania, with 50% inhibitory concentrations (IC50 ) values ranging from 39-100 µg/mL. The CHCl3 extract of the stem bark returned IC50 values of 39 and 40.6 µg/mL for L. amazonensis and L. braziliensis, respectively. The drimanes were relatively effective: 1-β-(p-coumaroyloxy)-polygodial produced IC50 values of 5.55 and 2.52 µM for L. amazonensis and L. braziliensis, respectively, compared with 1-β-(p-methoxycinnamoyl)-polygodial, which produced respective IC50 values of 15.85 and 17.80 µM. The CHCl3 extract demonstrated activity (IC50 of 3.0 µg/mL) against P. falciparum. The IC50 values of 1-β-(p-cumaroyloxyl)-polygodial and 1-β-(p-methoxycinnamoyl)-polygodial were 1.01 and 4.87 µM, respectively, for the trophozoite strain. Therefore, the results suggest that D. brasiliensis is a promising plant from which to obtain new and effective antiparasitic agents.


Assuntos
Antiprotozoários/farmacologia , Drimys/química , Leishmania braziliensis/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos/farmacologia , Antimaláricos/farmacologia , Testes de Sensibilidade Parasitária
13.
Pharm Biol ; 49(9): 907-19, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21592008

RESUMO

CONTEXT: Subcutaneous mycoses are chronic infections caused by slow growing environmental fungi. Latin American plants are used in folk medicine to treat these afflictions. Moreover, the potential of the rich Latin American biodiversity for this purpose has not been fully explored. OBJECTIVES: The aim of the study was to screen Latin American plant extracts against two species of subcutaneous fungi: Sporothrix schenckii and Fonsecaea pedrosoi. MATERIALS AND METHODS: One hundred ninety-five organic extracts from 151 Latin American plants were screened against two subcutaneous fungi by the agar dilution method at a concentration of 100 µg/mL, and minimum inhibitory concentrations (MICs) of active extracts were determined. Positive (amphothericin B) and negative (50% ethanol) controls were used. RESULTS AND DISCUSSION: Twenty eight extracts showed activity at ≤100 µg/mL. Of these, four extracts from Gnaphalium gaudichaudianum DC (Asteraceae), Plumeria rubra L (Apocynaceae), Tecoma stans (L.) Juss. ex Kunth. (Bignoniaceae), and Trichostigma octandum (L.), H. Walter showed activity against F. pedrosoi at MIC 12.5 µg/mL; and, four extracts from Bourreria huanita (Lex.) Hemsl. (Boraginaceae), Phytolacca bogotensis Kunth (Phytolaccaceae), Monnina xalapensis Kunth (Polygalaceae) and Crataegus pubescens (C. Presl) C. Presl (Rosaceae) against S. schenckii. This is the first report on antifungal activity of the Latin American plants against these two subcutaneous fungi. CONCLUSION: S. schenkii and F. pedrosoi were inhibited by B. huanita (MIC: 12.5 and 25 µg/mL), G. gaudichaudianum (MIC: 50 and 12.5 µg/mL) and T. triflora (MIC: 25 µg/mL).


Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Micoses/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Sporothrix/efeitos dos fármacos , Anfotericina B/farmacologia , Antifúngicos/análise , Antifúngicos/uso terapêutico , Etanol/farmacologia , Fungos/efeitos dos fármacos , Humanos , América Latina , Medicina Tradicional , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/uso terapêutico , Terminalia/química , Terminalia/metabolismo
14.
Pharm Biol ; 48(5): 545-53, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20645798

RESUMO

In order to explore rationally the medical potential of the plant biodiversity of the Central and South American region as a source of novel antiparasitic molecules, a multinational Organization of American States (OAS) project, which included the participation of multidisciplinary research centers from Argentina, Bolivia, Colombia, Costa Rica, Guatemala, Nicaragua and Panama, was carried out during the period 2001-2004. This project aimed at screening organic plant extracts for antitrypanosomal, antileishmanial and antimalarial activities and subsequently isolating and characterizing bioactive molecules. Plants for antiparasitic screening were selected from a database of ethnomedical uses of Latin American plants (PlanMedia) based on the amount of biological and chemical information available in the literature. We report here the evaluation of 452 extracts from 311 plant species in vitro screens against Plasmodium falciparum, Leishmania mexicana, and Trypanosoma cruzi. Out of 311 species tested, 17 plants (5.4%) showed antiparasitic activities at IC(50) values < or = 10 microg/mL. The most active plants were Acnistus arborescens (L.) Schltdl. (Solanaceae) (leaf, EtOH, IC(50): 4 microg/mL) Monochaetum myrtoideum Naudin (Melastomataceae) (leaf, MeOH, IC(50): 5 microg/mL) and Bourreria huanita (Lex.) Hemsl. (Boraginaceae) (branch, EtOH, IC(50): 6 microg/mL). These were selectively active against P. falciparum, L. mexicana and T. cruzi, respectively.


Assuntos
Antimaláricos/uso terapêutico , Antiparasitários/uso terapêutico , Doença de Chagas , Leishmaniose , Malária , Extratos Vegetais/uso terapêutico , Antimaláricos/isolamento & purificação , Antiparasitários/isolamento & purificação , Doença de Chagas/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , América Latina , Leishmaniose/tratamento farmacológico , Malária/tratamento farmacológico , Extratos Vegetais/isolamento & purificação , Plantas , Distribuição Aleatória
15.
Planta Med ; 76(4): 365-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19830657

RESUMO

The aim of this work is the isolation of anti-leishmanial compounds from the ethyl acetate extracts of the bark of HEDYOSMUM ANGUSTIFOLIUM. We have successfully isolated and characterized five sesquiterpenes: one new compound (oxyonoseriolide, 1), one compound isolated for the first time from a natural source (hedyosmone, 2), and three known sesquiterpenes (onoseriolide, 3; chloranthalactone A, 4; and spathulenol, 5) that had not been previously isolated from H. ANGUSTIFOLIUM. The biological activities of 1- 5 showed that onoseriolide ( 3) was the most active compound against axenic amastigotes from LEISHMANIA AMAZONENSIS and L. INFANTUM. Moreover, it was still active on the intramacrophagic amastigotes of L. INFANTUM. The isolated compounds have also been tested on PLASMODIUM FALCIPARUM and against various mammalian cell lines.


Assuntos
Antimaláricos/farmacologia , Leishmania/efeitos dos fármacos , Magnoliopsida/química , Extratos Vegetais/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos/farmacologia , Tripanossomicidas/farmacologia , Animais , Antimaláricos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Chlorocebus aethiops , Humanos , Neoplasias/tratamento farmacológico , Testes de Sensibilidade Parasitária , Casca de Planta , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/uso terapêutico , Tripanossomicidas/isolamento & purificação , Células Vero
16.
J Ethnopharmacol ; 127(1): 137-58, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19782744

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: This study reports the antifungal evaluation of 327 plant species (92 families and 251 genera) from seven Latin American countries which were selected on the basis of their reported ethnomedical uses and compared them with plants selected at random. AIM OF THE STUDY: (a) The main aim of this study was to investigate whether the probability of detecting antifungal plants is higher when plants have reports of ethnopharmacological uses related to fungal infections (PAU group) than when they are selected at random (PNAU group). (b) The second objective was to determine, within the PAU group, whether the probability of obtaining a positive result will be higher when the plants are tested against dermatophytes, than against yeasts or Aspergillus spp. (c) The third goal was to investigate, within all MICs0.05). (c) Within the detected antifungal plants from both groups, plants of the PAU group displayed higher activities (lower MICs) than those of PNAU group against dermatophytes (p<0.05) but not against yeasts or Aspergillus spp. CONCLUSIONS: Considering that dermatophytes are the cause of superficial fungal infections, which can be easily detected and followed by traditional healers, our findings suggest that the ethnopharmacological approach is useful in guiding the detection of antifungal plants in Latin America mainly for infections in which the pathological expression is obvious and, therefore, the cure can be clearly observed.


Assuntos
Antifúngicos , Descoberta de Drogas/métodos , Etnofarmacologia/métodos , Fungos/efeitos dos fármacos , Conhecimentos, Atitudes e Prática em Saúde , Plantas Medicinais , Antifúngicos/farmacologia , Arthrodermataceae/efeitos dos fármacos , Aspergillus/efeitos dos fármacos , Coleta de Dados , Avaliação Pré-Clínica de Medicamentos/métodos , América Latina , Medicina Tradicional , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Fitoterapia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Especificidade da Espécie , Estatística como Assunto , Terminologia como Assunto , Leveduras/efeitos dos fármacos
17.
Chem Biol Interact ; 180(2): 312-7, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19497430

RESUMO

As part of our continuing search for bioactive natural products from plants, the present study was carried out in order to evaluate the gastroprotective properties of alkaloid extract and 2-phenylquinoline obtained from the bark of Galipea longiflora (Rutaceae). Anti-ulcer assays were performed using the following protocols in mice: nonsteroidal anti-inflammatory drug (NSAID)/bethanecol-induced ulcer, ethanol/HCl-induced ulcer, and stress-induced ulcer. The effects of the extract on gastric content volume, pH and total acidity were also evaluated, using the pylorus ligated model. Treatment using doses of 50, 125 and 250 mg/kg of G. longiflora alkaloid extract and positive controls (omeprazol or cimetidine) significantly diminished the lesion index, total lesion area, and percentage of lesion, in comparison with the negative control groups in all the models evaluated. Regarding the model of gastric secretion, a reduction in volume of gastric juice and total acidity was observed, as well as an increase in gastric pH. The main alkaloid of the plant, 2-phenylquinoline, was also evaluated in the ethanol-induced ulcer model. The results showed that at a dose of 50 mg/kg, it significantly inhibited ulcerative lesions. However, this effect was less than that of the alkaloid extract. All these results taken together show that G. longiflora displays gastroprotective activity, as evidenced by its significant inhibition of the formation of ulcers induced by different models. There are indications that mechanisms involved in anti-ulcer activity are related to a decrease in gastric secretion and an increase in gastric mucus content. Also, there is evidence of involvement of NO in the gastroprotector mechanisms. These effects may be attributed, at least in part, to the presence of some alkaloids, particularly 2-phenylquinoline.


Assuntos
Alcaloides/farmacologia , Extratos Vegetais/farmacologia , Quinolinas/farmacologia , Rutaceae/química , Úlcera Gástrica/prevenção & controle , Alcaloides/química , Animais , Antiulcerosos/química , Antiulcerosos/farmacologia , Betanecol/toxicidade , Relação Dose-Resposta a Droga , Etanol/toxicidade , Ácido Clorídrico/toxicidade , Indometacina/toxicidade , Camundongos , Estrutura Molecular , Casca de Planta/química , Extratos Vegetais/química , Quinolinas/química , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente
18.
Biofarbo ; 16: 47-53, dic. 2008. tab
Artigo em Espanhol | LILACS, MTYCI | ID: biblio-997955

RESUMO

El presente artículo describe la validación de un método de cuali-cuantificación de alcaloides quinolínicos por espectrofotometría UV con máximos de absorción de 330-335nm de longitud de onda. Para su cuantificación el extracto de alcaloides es disuelto en ácido clorhídrico 1N, al 0,05 %p/v y se preparan 12 diluciones 1:2. El método cumple con los requerimientos de exactitud y precisión con límites de detección y cuantificación entre 0,567-7,81 µg/mL y 1,72-7,81 µg/mL para los alcaloides quinolínicos respectivamente. Se obtuvieron respuestas lineales entre 0,244­7,81 µg/mL con un coeficiente de determinación de 0,997. Se verificó la robustez del procedimiento aplicando tres variables, temperatura, luz UV y pH. (AU)


Assuntos
Humanos , Plantas Medicinais , Ácidos Quinolínicos , Extratos Vegetais , Leishmaniose , Alcaloides , Espectrofotometria , Bolívia
19.
J Nat Prod ; 71(9): 1538-43, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18712933

RESUMO

Piper glabratum and P. acutifolium were analyzed for their content of main secondary constituents, affording nine new benzoic acid derivatives (1, 2, 4, 5, 7, and 10-13), in addition to four known compounds (3, 6, 8, and 9). Their structures were elucidated on the basis of spectroscopic data. Riguera ester reactions and optical rotation measurements established the new compounds as racemates. In the search for antiparasitic agents, the compounds were evaluated in vitro against the promastigote forms of Leishmania spp., Trypanosoma cruzi, and Plasmodium falciparum. Among the evaluated compounds, methyl 3,4-dihydroxy-5-(3'-methyl-2'-butenyl)benzoate (7) exhibited leishmanicidal effect (IC50 13.8-18.5 microg/mL) against the three Leishmania strains used, and methyl 3,4-dihydroxy-5-(2-hydroxy-3-methylbutenyl)benzoate (1), methyl 4-hydroxy-3-(2-hydroxy-3-methyl-3-butenyl)benzoate (3), and methyl 3,4-dihydroxy-5-(3-methyl-2-butenyl) benzoate (7) showed significant trypanocidal activity, with IC50 values of 16.4, 15.6, and 18.5 microg/mL, respectively.


Assuntos
Antiparasitários/isolamento & purificação , Antiparasitários/farmacologia , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Benzoatos/isolamento & purificação , Benzoatos/farmacologia , Piper/química , Plantas Medicinais/química , Animais , Antimaláricos , Antiparasitários/química , Antiprotozoários/química , Benzoatos/química , Bolívia , Leishmania/efeitos dos fármacos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Folhas de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Trypanosoma cruzi/efeitos dos fármacos
20.
Planta Med ; 73(3): 206-11, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17354169

RESUMO

The kavapyrone (+)-(7 R,8 S)-epoxy-5,6-didehydrokavain (1) and the chalcone flavokavain B (2) were isolated from Piper rusbyi as the bioactive components by bioassay-guided fractionation, using an in vitro assay against promastigote forms of three Leishmania strains. In addition, the new kavapyrone, (7 R,8 R/7 S,8 S)-dihydroxy-5,6-didehydrokavain (3), which is very likely an artifact, and four known compounds (4-7) were isolated. Their structures were elucidated on the basis of spectral analysis, and the absolute configurations of compounds 1 and 3 were established by CD studies and the modified Mosher ester procedure, respectively. All compounds were evaluated for in vitro leishmanicidal activity. The most active compounds 1 (IC50=81.9 microM) and 2 (IC50=11.2 microM) were also evaluated in vivo against a New World strain of cutaneous leishmaniasis, and the results showed the efficacy of 2 at a dose of 5 mg/kg/day. Compounds 1 and 3 were also assayed as reversal agents against a multidrug-resistant Leishmania tropica line, but were found to be inactive.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Fitoterapia , Piper , Extratos Vegetais/farmacologia , Animais , Antiprotozoários/administração & dosagem , Antiprotozoários/uso terapêutico , Leishmania/classificação , Leishmaniose/tratamento farmacológico , Testes de Sensibilidade Parasitária , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Folhas de Planta
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