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1.
J Nat Prod ; 82(12): 3233-3241, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31800248

RESUMO

Six new secocycloartane glycosides (1-6) were isolated from the ethanol extract of the flowers of Cordia lutea Lam. on the basis of bioassay-guided fractionation. Their structures were determined by the application of NMR and MS data analyses together with X-ray crystallographic analyses for compounds 1 and 2. Compounds 1-6 represent the first examples of 9,10-seco-29-norcycloartane glycosides. These compounds showed significant in vitro anti-Helicobacter pylori activity, and no activity against either Escherichia coli or Pseudomonas aeruginosa. Significant activity was observed for 5 and 6 against Staphylococcus aureus. All compounds displayed weak cytotoxicity against RAW 264.7 cells. The in vitro antileishmanial and antiplasmodial activities of 1-6 were also evaluated.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Cordia/química , Flores/química , Glicosídeos/química , Glicosídeos/farmacologia , Plantas Medicinais/química , Animais , Antibacterianos/isolamento & purificação , Antiprotozoários/isolamento & purificação , Cristalografia por Raios X , Glicosídeos/isolamento & purificação , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Plasmodium falciparum/efeitos dos fármacos , Células RAW 264.7 , Análise Espectral/métodos
2.
J Insect Sci ; 19(6)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31865367

RESUMO

Helicobacter pylori (Marshall & Goodwin) is a widespread human pathogen that is acquiring resistance to the antibiotics used to treat it. This increasing resistance necessitates a continued search for new antibiotics. An antibiotic source that shows promise is animals whose immune systems must adapt to living in bacteria-laden conditions by producing antibacterial peptides or small molecules. Among these animals is the black soldier fly (BSF; Hermetia illucens Linnaeus), a Diptera that colonizes decomposing organic matter. In order to find anti-H. pylori peptides in BSF, larvae were challenged with Escherichia coli (Enterobacteriales: Enterobacteriaceae). Small peptides were extracted from hemolymph and purified using solid-phase extraction, molecular weight cutoff filtration and two rounds of preparative high performance liquid chromatography (HPLC). The anti-H. pylori fraction was followed through the purification process using the inhibition zone assay in brain-heart infusion agar, while peptides from uninoculated larvae had no activity. The inhibition halo of the active sample was comparable to the action of metronidazole in the inhibition zone assay. The purified sample contained four peptides with average masses of approximately 4.2 kDa that eluted together when analyzed by HPLC-mass spectrometry. The peptides likely have similar sequences, activity, and properties. Therefore, BSF produces inducible antibacterial peptides that have in vitro activity against H. pylori, which highlights BSF's position as an important target for further bioprospecting.


Assuntos
Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Dípteros/química , Helicobacter pylori , Animais , Bioprospecção , Escherichia coli , Larva/química , Testes de Sensibilidade Microbiana
3.
Planta Med ; 80(11): 902-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25029171

RESUMO

Seven benzo[c]phenanthridines, synthetic or isolated from Zanthoxylum rhoifolium root bark, were evaluated against Leishmania amazonensis axenic amastigotes. Five of them were considered leishmanicidal, with IC50 values ranging from 0.03 to 0.54 µM, and were evaluated on intramacrophagic amastigotes of L. amazonensis. Chelerythrine displayed the best activity (IC50=0.5 µM), which was in the same range as the reference compound amphotericin B (IC50=0.4 µM). In vivo studies with chelerythrine, avicine, and fagaridine on a model of mice cutaneous leishmaniasis resulted in the identification of fagaridine as the most active compound. Fagaridine decreased the parasitic burden more than 50% at the 3rd and 6th weeks after the end of treatment.


Assuntos
Leishmania/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Fenantridinas/farmacologia , Extratos Vegetais/farmacologia , Zanthoxylum/química , Animais , Benzofenantridinas/química , Benzofenantridinas/isolamento & purificação , Benzofenantridinas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Concentração Inibidora 50 , Leishmaniose Cutânea/parasitologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Parasitária , Fenantridinas/química , Fenantridinas/isolamento & purificação , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Plantas Medicinais
4.
Cancers (Basel) ; 16(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38672558

RESUMO

We explored the clinical-stage association of gastric intestinal metaplasia (IM) compared to cases of chronic non-atrophic gastritis (CNAG) and its relationship with virulence genotypes of Helicobacter pylori (H. pylori) clinical isolates from patients with dyspepsia in Peru. This study was cross-sectional and included 158 H. pylori clinical isolates; each isolate corresponded to a different Peruvian patient, genotyped by polymerase chain reaction to detect cagA gene and EPIYA motifs, the vacA gene (alleles s1, s2, i1, i2, d1, d2, m1, m2 and subtypes s1a, s1b and s1c), the iceA gene (alleles 1 and 2), and the babA gene (allele 2). We observed that 38.6% presented with IM and that all clinical isolates were CagA positive. The EPIYA-ABC motif was predominant (68.4%), and we observed a high frequency for the vacA gene alleles s1 (94.9%), m1 (81.7%), i1 (63.9%), and d1 (70.9%). Strains with both iceA alleles were also detected (69.6%) and 52.2% were babA2 positive. In addition, it was observed that the cagA+/vacAs1m1 (PR: 2.42, 1.14 to 5.13, p < 0.05) and cagA+/vacAs1am1 (PR: 1.67, 1.13 to 2.45, p < 0.01) genotypes were associated with IM. Our findings revealed the cagA and vacA risk genotypes predominance, and we provided clinically relevant associations between Peruvian patients with H. pylori infection and IM clinical stage.

5.
Planta Med ; 78(9): 914-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22516933

RESUMO

Two new dihydrochalcones (1, 2), as well as eight known compounds, piperaduncin C (3), 2',6'-dihydroxy-4'-methoxydihydrochalcone (4), 4,2',6'-trihydroxy-4'-methoxydihydrochalcone (5), 4-hydroxy-3,5-bis(3-methyl-2-butenyl)-benzoic acid (6), 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoic acid (7), 4-hydroxy-3-(3-methyl-2-butenoyl)-5-(3-methyl-2-butenyl)-benzoic acid (8), 2,2-dimethyl-8-(3-methyl-2-butenyl)-2H-1-chromene-6-carboxylic acid (9), and 3-(3',7'-dimethyl-2',6'-octadienyl)-4-methoxybenzoic acid (10) were isolated from the leaves of Piper dennisii Trelease (Piperaceae), using a bioassay-guided fractionation to determine their antileishmanial potential. Among them, compound 10 exhibited the best antileishmanial activity (IC50 = 20.8 µM) against axenic amastigote forms of Leishmania amazonensis, with low cytotoxicity on murine macrophages. In the intracellular macrophage-infected model, compound 10 proved to be more active (IC50 = 4.2 µM). The chemical structures of compounds 1-10 were established based on the analysis of the spectroscopic data.


Assuntos
Antiprotozoários/farmacologia , Chalconas/química , Chalconas/farmacologia , Leishmania/efeitos dos fármacos , Piper/química , Animais , Antiprotozoários/química , Benzoatos/química , Benzoatos/farmacologia , Ácido Benzoico/química , Avaliação Pré-Clínica de Medicamentos/métodos , Éteres de Hidroxibenzoatos , Concentração Inibidora 50 , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Camundongos , Estrutura Molecular , Folhas de Planta/química
6.
Fitoterapia ; 158: 105172, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35283240

RESUMO

Four undescribed secocycloartane monoglycosides (1-4) were isolated from an ethanolic extract of the dry flowers of Cordia lutea Lam. Their structural assignment is based on NMR and MS analysis. Their stereochemistry is confirmed by molecular modelling studies using DFT-NMR calculations done for compound 3. In vitro antibacterial activity of the four compounds was moderate on Helicobacter pylori (MIC = 15.6 µg/mL), and much weaker on Staphylococcus aureus, Pseudomonas aeruginosa or Escherichia coli (MIC >125 µg/mL). Toxicity evaluated against RAW 264.7 cells was weak (IC50 values ranging from 24 to 41 µM i.e. 15 to 24 µg/mL), but in the same range as anti-Helicobacter activity.


Assuntos
Cordia , Antibacterianos , Cordia/química , Glicosídeos/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química
7.
Plants (Basel) ; 11(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35448739

RESUMO

We explored the concentration patterns of the bioactive metabolite plumericin produced by Himatanthus tarapotensis (Apocynaceae) under different edaphic conditions and variations in rainfall intensity, as well as its potential role in the chemical defense against insect herbivores. Values of plumericin concentration from leaves were obtained by High-Performance Liquid Chromatography, and evaluated as a function of differences in soil types, variation of precipitation, and variation of the abundance of insect herbivores, using first a Repeated Measures Correlation (rmcorr) and then a Generalized Linear Mixed Model (GLMM) analysis. Plumericin concentration is highly variable among plants, but with a significantly higher concentration in plants growing on clay soil compared to that of the white-sand soil habitat (p < 0.001). Plumericin concentration is not affected by precipitation. The caterpillar of Isognathus leachii (Lepidoptera: Sphingidae) is the most conspicuous herbivore of H. tarapotensis, and its presence is continuous but not related to plumericin concentration, probably because of its capacity to elude the chemical defense of this plant. Nevertheless, our multivariate model revealed that plumericin concentration is related to the abundance of Hymenoptera (Formicidae), and this relationship is significantly influenced by the soil parameters of carbon percentage, clay percentage, and phosphorous percentage (p < 0.001). Plumericin is a mediating agent in the interaction between H. tarapotensis and its natural environment. Variation in plumericin concentration would be induced by the abundance of Hymenoptera (Formicidae), probably as a chemical response against these insects, and by differences in soil nutrient availability.

8.
Planta Med ; 77(6): 672-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21104602

RESUMO

Members of the Curcuma plant species (Zingiberaceae) have been used for centuries in cooking, cosmetics, staining and in traditional medicine as "omnipotent" remedies. Herbal preparations made with, and molecules extracted from, Curcuma have been shown to possess a wide variety of pharmacological properties against malignant proliferation, hormonal disorders, inflammation, and parasitosis among other conditions. This review evaluates Curcuma and its associated bioactive compounds, particularly focusing on studies examining the parasiticidal activity of these components against the tropical parasites Plasmodium, leishmania, Trypanosoma, Schistosoma and more generally against other cosmopolitan parasites (nematodes, Babesia, Candida, Giardia, Coccidia and Sarcoptes).


Assuntos
Antiparasitários/farmacologia , Curcuma/química , Curcumina/farmacologia , Parasitos/efeitos dos fármacos , Doenças Parasitárias/tratamento farmacológico , Preparações de Plantas/farmacologia , Animais , Antiparasitários/química , Antiparasitários/uso terapêutico , Babesiose/tratamento farmacológico , Babesiose/parasitologia , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Curcumina/química , Curcumina/uso terapêutico , Giardíase/tratamento farmacológico , Giardíase/parasitologia , Helmintíase/tratamento farmacológico , Helmintíase/parasitologia , Humanos , Leishmaniose/tratamento farmacológico , Leishmaniose/parasitologia , Malária/tratamento farmacológico , Malária/parasitologia , Parasitos/patogenicidade , Doenças Parasitárias/parasitologia , Preparações de Plantas/química , Preparações de Plantas/uso terapêutico , Escabiose/tratamento farmacológico , Escabiose/parasitologia , Esquistossomose/tratamento farmacológico , Esquistossomose/parasitologia , Tripanossomíase/tratamento farmacológico , Tripanossomíase/parasitologia
9.
Planta Med ; 77(14): 1597-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21472652

RESUMO

An anticancer-bioassay guided isolation of the ethanol extract and fractions of two plants from the Peruvian rainforest, Mikania decora and Cremastosperma microcarpum, led to the characterization of one abundant diterpene, ent-pimara-8(14),15-dien-19-oic acid (1), three thymol derivatives, 10-acetoxy-8,9-dehydro-6-methoxythymol butyrate (2), 10-acetoxy-8,9-epoxy-6-methoxythymol isobutyrate (3), and acetylschizoginol (4), as well as one neolignan, (±)-trans-dehydrodiisoeugenol (5). Only the latter was isolated from C. microcarpum. These compounds exhibited significant cytotoxic activity against a panel of human tumor cell lines. Compounds 3 and 4 were also investigated for their in vitro antileishmanial and trypanocidal activity against Leishmania amazonensis axenic amastigotes and Trypanosoma cruzi trypomastigotes.


Assuntos
Annonaceae/química , Anti-Infecciosos/farmacologia , Mikania/química , Extratos Vegetais/química , Animais , Anti-Infecciosos/química , Linhagem Celular Tumoral , Sobrevivência Celular , Diterpenos/química , Diterpenos/farmacologia , Feminino , Humanos , Leishmania/efeitos dos fármacos , Lignanas/química , Lignanas/farmacologia , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Testes de Sensibilidade Parasitária , Peru , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Timol/química , Timol/farmacologia , Árvores , Trypanosoma cruzi/efeitos dos fármacos
10.
Rev Peru Med Exp Salud Publica ; 38(3): 406-411, 2021.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-34932742

RESUMO

OBJECTIVE: To analyze the antimicrobial susceptibility of Helicobacter pylori to 5 reference antibiotics, in a population of 500 dyspeptic patients from the Gastroenterology Service of the Cayetano Heredia Hospital (n = 419) and the Cayetano Heredia Clinic (n = 81) in Lima, Peru. MATERIALS AND METHODS: Gastric biopsies were collected from 500 patients diagnosed with dyspepsia. From these biopsies, 273 H. pylori strains were isolated and cultured to confirm H. pylori infection by histological and culture diagnosis. Finally, antimicrobial susceptibility was analyzed using the broth microdilution method, and the resistance profiles of each antimicrobial and multi-resistance patterns were evaluated by statistical analysis. RESULTS: The diagnosis of H. pylori infection by culture, compared to histological testing, reported a sensitivity of 83.8%, a specificity of 89.9% and an area under the curve (AUC) of 0.87 (95% CI: 0.84 to 0.90). The frequency of infection in the gastroenterology services of the Cayetano Heredia Hospital and Clinic was 56.6% (237/419) and 44.4% (36/81), respectively. An increase in antimicrobial resistance to Amoxicillin (45.1% / 29.6%), Levofloxacin (71.8%/ 74.1%) and Metronidazole (69.8% / 63.0%) was found in the Hospital and the Clinic, respectively. Multiple resistance patterns showed that the most frequent resistance (double and triple) was to Levofloxacin, Metronidazole and Amoxicillin. CONCLUSIONS: The antimicrobial resistance of H. pylori has increased compared to that reported in previous years. Furthermore, H. pylori multiple resistance presents high frequencies in infected patients. The broth microdilution method could be implemented in different hospitals in Peru as a surveillance tool for H. pylori antimicrobial resistance.


OBJETIVO: Analizar la susceptibilidad antimicrobiana de Helicobacter pylori a 5 antibióticos de referencia, en pacientes dispépticos del Servicio de Gastroenterología del Hospital Cayetano Heredia y la Clínica Cayetano Heredia en Lima, Perú. MATERIALES Y MÉTODOS: Se colectaron biopsias gástricas de 500 pacientes diagnosticados con dispepsia. A partir de estas biopsias, se aislaron y cultivaron 273 cepas de H. pylori para confirmar la infección mediante el diagnóstico histológico y por cultivo. Finalmente, se analizó la susceptibilidad antimicrobiana mediante el método de microdilución en caldo y se evaluaron los perfiles de resistencia de cada antimicrobiano y los patrones de multirresistencia. RESULTADOS: El diagnóstico de H. pylori por cultivo, comparado con la prueba histológica, reportó una sensibilidad del 83,8%, una especificidad del 89,9% y un área bajo la curva de 0,87 (IC95%: 0,84 a 0,90). La frecuencia de la infección en los servicios de gastroenterología del Hospital y la Clínica Cayetano Heredia fueron del 56,6% (237/419) y 44,4% (36/81), respectivamente. Según el Hospital/Clínica, se determinó la resistencia para amoxicilina (45,1%/29,6%), levofloxacino (71,8%/74,1%) y metronidazol (69,8%/63,0%). Los patrones de resistencia a múltiples antimicrobianos demostraron que las resistencias (dobles y triples) más frecuentes fueron con levofloxacino, metronidazol y amoxicilina. CONCLUSIONES: La resistencia antimicrobiana de H. pylori ha aumentado con respecto a los años previos. Además, la resistencia múltiple de H. pylori presenta altas frecuencias en pacientes infectados. El método de microdilución en caldo podría ser implementado en los diferentes hospitales del Perú como una herramienta de vigilancia de la resistencia de H. pylori a los antimicrobianos.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/epidemiologia , Humanos , Laboratórios , Testes de Sensibilidade Microbiana , Peru/epidemiologia
11.
Rev Peru Med Exp Salud Publica ; 38(3): 424-433, 2021.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-34932744

RESUMO

OBJECTIVE: To evaluate the toxicity of three synthetic chalcones administered intraperitoneally to BALB/c mice. MATERIALS AND METHODS: The median lethal dose (LD50) was estimated by Dixon's Up-and-Down method. Subchronic toxicity of chalcones was evaluated at 20 and 40 mg/kg for 21 days. Behavioral, physiological, biochemical, and histological toxic effects were evaluated. RESULTS: Chalcone 43 produced mucus in feces, visceral damage (liver) and alterations in organ coefficient (kidney, p = 0.037 and brain, p = 0.008) when compared to the control group. In addition, histological analysis showed that this chalcone produced edema, inflammation and necrosis in the evaluated organs, although there was no significant difference with the control. None of the biochemical parameters differed significantly between the treatment groups at 40 mg/kg dose and the control. CONCLUSIONS: The LD50 for all three chalcones was greater than 550 mg/kg of body weight. Chalcones 40 and 42 were found to be relatively non-toxic. Both can be considered safe for intraperitoneal application in BALB/c mice and, consequently, are potential candidates for use in the treatment of leishmaniasis.


OBJETIVO: Evaluar la toxicidad de tres chalconas sintéticas administradas por vía intraperitoneal en ratones BALB/c. MATERIALES Y MÉTODOS: La dosis letal media (DL50) se estimó por el método Up-and-Down de Dixon. La toxicidad subcrónica de las chalconas se evaluó a 20 y 40   mg/kg por 21 días. Se evaluó el efecto tóxico a nivel de comportamiento, fisiológico, bioquímico e histológico. RESULTADOS: La chalcona 43 generó moco en las heces, daño visceral (hígado) y alteración en el coeficiente de órganos (riñón, p   =   0,037 y cerebro, p   =   0,008) en comparación con el grupo control. Además, en el análisis histológico se observó que esta chalcona produjo edema, inflamación y necrosis en los órganos evaluados, aunque no hubo diferencia significativa con el control. Todos los parámetros bioquímicos no difirieron significativamente entre los grupos de tratamiento a dosis de 40   mg/kg y el control. CONCLUSIONES: La DL50 para las tres chalconas fue superior a 550   mg/kg de peso corporal. Las chalconas 40 y 42 son relativamente no tóxicas. Ambas pueden considerarse seguras para la aplicación vía intraperitoneal en ratones BALB/c y, en consecuencia, son posibles candidatas para ser usadas en el tratamiento contra las leishmaniosis.


Assuntos
Antiprotozoários , Chalcona , Chalconas , Leishmaniose , Animais , Antiprotozoários/uso terapêutico , Chalconas/toxicidade , Camundongos , Camundongos Endogâmicos BALB C
12.
Bioorg Med Chem Lett ; 20(1): 100-3, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19962891

RESUMO

The in vitro screening of 43 polysubstituted chalcones against Leishmania amazonensis axenic amastigotes, led to the evaluation of 9 of them in a macrophage-infected model with the two other most infectious Leishmania species prevalent in Peru (L. braziliensis and L. peruviana). The five most active and selective chalcones were studied in vivo, resulting on the identification of two chalcones with high reduction parasite burden percentages.


Assuntos
Antiprotozoários/síntese química , Chalconas/síntese química , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Chalconas/química , Chalconas/farmacologia , Leishmania/efeitos dos fármacos , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Parasitária
13.
Bioorg Med Chem ; 18(8): 2880-6, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20356752

RESUMO

The synthesis of 2-(5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidin-4-yl)hydrazone-derivatives (BTPs) and their in vitro evaluation against Trypanosoma cruzi trypomastigotes, Mycobacterium tuberculosis, Leishmania amazonensis axenic amastigotes, and six human cancer cell lines is described. The in vivo activity of the most active and least toxic compounds against T. cruzi and L. amazonensis was also studied. BTPs constitute a new family of drug leads with potential activity against infectious diseases. Due to their drug-like properties, this series of compounds can potentially serve as templates for future drug-optimization and drug-development efforts for use as therapeutic agents in developing countries.


Assuntos
Antituberculosos/química , Pirimidinas/química , Antiprotozoários/síntese química , Antiprotozoários/química , Antiprotozoários/toxicidade , Antituberculosos/síntese química , Antituberculosos/toxicidade , Linhagem Celular Tumoral , Humanos , Mycobacterium tuberculosis/efeitos dos fármacos , Testes de Sensibilidade Parasitária , Pirimidinas/toxicidade , Trypanosoma cruzi/efeitos dos fármacos
14.
J Nat Prod ; 73(11): 1884-90, 2010 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-20954722

RESUMO

Three new caffeic acid esters (1-3), four new lignans (4-7), and the known compounds (7'S)-parabenzlactone (8), dihydrocubebin (9), and justiflorinol (10) have been isolated from leaves of Piper sanguineispicum. Their structures were determined by spectroscopic methods, including 1D and 2D NMR, HRCIMS, CD experiments, and chemical methods. Compounds 1-10 were assessed for their antileishmanial potential against axenic amastigote forms of Leishmania amazonensis. Caffeic acid esters 1 and 3 exhibited the best antileishmanial activity (IC(50) 2.0 and 1.8 µM, respectively) with moderate cytotoxicity on murine macrophages.


Assuntos
Ácidos Cafeicos/isolamento & purificação , Citotoxinas/isolamento & purificação , Leishmania/efeitos dos fármacos , Lignanas/isolamento & purificação , Macrófagos/efeitos dos fármacos , Piper/química , Animais , Ácidos Cafeicos/química , Ácidos Cafeicos/farmacologia , Chlorocebus aethiops , Citotoxinas/química , Citotoxinas/farmacologia , Dioxolanos/química , Dioxolanos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Ésteres , Feminino , Concentração Inibidora 50 , Lignanas/química , Lignanas/farmacologia , Camundongos , Ressonância Magnética Nuclear Biomolecular , Peru , Folhas de Planta/química , Células Vero
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.
Planta Med ; 76(7): 705-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19960415

RESUMO

A pharmacological screening of the ethanol extract and fractions of two Peruvian medicinal plants, Plagiochila disticha and Ambrosia peruviana, led to the isolation and characterization of three ENT-2,3-secoaromadendrane-type sesquiterpenoids, named plagiochiline A ( 1), I ( 2), and R ( 3), as well as of two pseudoguaianolids, damsin ( 4) and confertin ( 5), which exhibited significant cytotoxic activity against a panel of human tumor cell lines. Compounds 1, 4, and 5 were also investigated for their in vitro antileishmanial, trypanocidal, and antituberculosis activity against Leishmania amazonensis axenic amastigotes and Trypanosoma cruzi trypomastigotes, as well as against MDR and sensitive strains of Mycobacterium tuberculosis, respectively.


Assuntos
Anti-Infecciosos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Asteraceae/química , Azulenos/isolamento & purificação , Compostos de Epóxi/isolamento & purificação , Piranos/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos , Peru , Plantas Medicinais/química
17.
J Nat Prod ; 72(3): 524-6, 2009 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-19199646

RESUMO

A multidisciplinary and international team of scientists was assembled in the early 1990s to conduct an ethnobotanical study of plants used by the Aguaruna people of the Peruvian Amazon forest. The initial ethnobotanical project, carried out under the auspices of an International Cooperative Biodiversity Grant (ICBG), led to the collection of approximately 4000 plant species. Some members of the original team of scientists have continued this collaboration by focusing on potential sources of new anticancer, anti-infective, and wound-healing agents. This effort has uncovered several secondary metabolites representing a wide variety of chemical diversity. In this short review we describe some bioactive compounds of interest as part of our continuing collaboration.


Assuntos
Plantas Medicinais/química , Etnobotânica , Humanos , Medicina Tradicional , Estrutura Molecular , Peru
18.
Mar Drugs ; 7(4): 640-53, 2009 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-20098604

RESUMO

As part of our search for new antimalarial drugs in South Pacific marine sponges, we have looked for inhibitors of Pfnek-1, a specific protein kinase of Plasmodium falciparum. On the basis of promising activity in a preliminary screening, the ethanolic crude extract of a new species of Pseudoceratina collected in Vanuatu was selected for further investigation. A bioassay-guided fractionation led to the isolation of a derivative of homogentisic acid [methyl (2,4-dibromo-3,6-dihydroxyphenyl)acetate, 4a] which inhibited Pfnek-1 with an IC(50) around 1.8 muM. This product was moderately active in vitro against a FcB1 P. falciparum strain (IC(50) = 12 muM). From the same sponge, we isolated three known compounds [11,19-dideoxyfistularin-3 (1), 11-deoxyfistularin-3 (2) and dibromo-verongiaquinol (3)] which were inactive against Pfnek-1. Synthesis and biological evaluation of some derivatives of 4a are reported.


Assuntos
Antimaláricos/farmacologia , Ácido Homogentísico/análogos & derivados , Ácido Homogentísico/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Poríferos/química , Inibidores de Proteínas Quinases/farmacologia , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antimaláricos/isolamento & purificação , Ensaios Enzimáticos , Ácido Homogentísico/isolamento & purificação , Inibidores de Proteínas Quinases/isolamento & purificação , Vanuatu
19.
Rev Peru Med Exp Salud Publica ; 36(2): 270-274, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31460640

RESUMO

In order to evaluate antimicrobial susceptibility and detect specific mutations in the 23S rRNA gene in Helicobacter pylori strains, a cross-sectional study was performed on 95 patients with dyspepsia treated in a private clinic in Lima. Antrum biopsies were collected by endoscopy for isolation and evaluation of antimicrobial susceptibility using the broth microdilution method. The detection of specific mutations was developed by PCR-RFLP. The percentage of infection by Helicobacter pylori was 46.3%. Resistance values of 52.3% to clarithromycin, 29.6% to metronidazole, 45.5% to levofloxacin, and 4.6% to amoxicillin were observed. The percentage of specific A2142G and A2143G mutations associated with clarithromycin resistance was 43.5%. In conclusion, we found that antimicrobial resistance rates and the percentage of Helicobacter pylori strains circulating in a private clinic in Lima were high.


Con el objetivo de evaluar la susceptibilidad antimicrobiana y detectar mutaciones puntuales en el gen ARNr 23S en cepas de Helicobacter pylori se realizó un estudio transversal que incluyó a 95 pacientes con dispepsia atendidos en una clínica privada de Lima. Mediante endoscopía se colectaron biopsias de antro para el aislamiento de cepas de Helicobacter pylori para la evaluación de la susceptibilidad antimicrobiana empleando la técnica de microdilución en caldo. La detección de mutaciones puntuales se desarrolló mediante PCR-RFLP. El porcentaje de infección por Helicobacter pylori fue de 46,3%, se observaron valores de resistencia de 52,3% a claritromicina, 29,6% a metronidazol, 45,5% a levofloxacino y 4,6% a amoxicilina. El porcentaje de mutaciones puntuales A2142G y A2143G asociados a resistencia a claritromicina fue 43,5%. En conclusión, encontramos que las tasas de resistencia antimicrobiana y el porcentaje de cepas de Helicobacter pylori circulantes en una clínica privada de Lima fueron elevadas.


Assuntos
Antibacterianos/farmacologia , Dispepsia/microbiologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Estudos Transversais , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Peru , RNA Ribossômico 23S/genética
20.
PLoS One ; 14(12): e0218837, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31860650

RESUMO

The gut microbiota of insects is composed of a wide range of microorganisms which produce bioactive compounds that protect their host from pathogenic attack. In the present study, we isolate and identify the fungus Chrysosporium multifidum from the gut of Hermetia illucens larvae. Extract from C. multifidum culture broth supernatant showed moderate activity against a strain of methicillin-resistant Staphylococcus aureus (MRSA). Bioguided isolation of the extract resulted in the characterization of six α-pyrone derivatives (1-6) and one diketopiperazine (7). Of these compounds, 5,6-dihydro-4-methoxy-6-(1-oxopentyl)-2H-pyran-2-one (4) showed the greatest activity (IC50 = 11.4 ± 0.7 µg/mL and MIC = 62.5 µg/mL) against MRSA.


Assuntos
Anti-Infecciosos/isolamento & purificação , Chrysosporium/química , Dípteros/microbiologia , Animais , Chrysosporium/isolamento & purificação , Fungos/química , Fungos/isolamento & purificação , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Larva/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana
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