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1.
J Ethnopharmacol ; 311: 116436, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37003399

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Mayaro virus (MAYV) is an arbovirus endemic to the Amazon region, which comprises the states of the North and Midwest region of Brazil and encompasses the largest tropical forest in the world, the Amazon Forest. The confirmation of its potential transmission by Aedes aegypti and recent cases in Brazil, mainly in large centers in the northern region, led to the classification of Mayaro fever as an emerging disease. Traditional medicine is commonly used to treat various diseases, mainly by local riverside populations. Some species of the genus Maytenus, which have similar morphologies, are popularly used to treat infections and inflammations. In this context, our research group has studied and confirmed the antiviral activity of several plant-derived compounds. However, several species of this same genus have not been studied and therefore deserve attention. AIM OF THE STUDY: This study aimed to demonstrate the effects of ethyl acetate extracts of leaves (LAE) and branches (TAE) of Maytenus quadrangulata against MAYV. MATERIALS AND METHODS: Mammalian cells (Vero cells) were used to evaluate the cytotoxicity of the extracts. After cell infection by MAYV and the treatment with the extracts, we evaluated the selectivity index (SI), the virucidal effect, viral adsorption and internalization, and the effect on viral gene expression. The antiviral action was confirmed by quantifying the viral genome using RT-qPCR and by analyzing the effect on virus yield in infected cells. The treatment was performed based on the effective concentration protective for 50% of the infected cells (EC50). RESULTS: The leaves (LAE; EC50 12.0 µg/mL) and branches (TAE; EC50 101.0 µg/mL) extracts showed significative selectivity against the virus, with SI values of 79.21 and 9.91, respectively, which were considered safe. Phytochemical analysis revealed that the antiviral action was associated with the presence of catechins, mainly in LAE. This extract was chosen for the subsequent studies since it reduced the viral cytopathic effect and virus production, even at high viral loads [MOI (multiplicity of infection) 1 and 5]. The effects of LAE resulted in a marked reduction in viral gene expression. The viral title was drastically reduced when LAE was added to the virus before infection or during replication stages, reducing virus production up to 5-log units compared to infected and untreated cells. CONCLUSION: Through kinetic replication, MAYV was not detected in Vero cells treated with LAE throughout the viral cycle. The virucidal effect of LAE inactivates the viral particle and can intercept the virus at the end of the cycle when it gains the extracellular environment. Therefore, LAE is a promising source of antiviral agents.


Asunto(s)
Alphavirus , Catequina , Maytenus , Animales , Chlorocebus aethiops , Antivirales/farmacología , Antivirales/química , Catequina/farmacología , Células Vero , Alphavirus/genética , Mamíferos
2.
Nat Prod Res ; 36(22): 5904-5909, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34994265

RESUMEN

The expression of virulence factors, such as biofilm formation, in association with the acquisition of resistance to multiple drugs, has evidenced the need for new and effective antimicrobial agents against Staphylococcus aureus. The evaluation of the pharmacological properties of plant-derived compounds is a promising alternative to the development of new antimicrobials. In this study, we aimed to evaluate the antibacterial, antibiofilm, and the synergistic and cytotoxic effects of netzahualcoyonol isolated from Salacia multiflora (Lam.) DC. roots. Netzahualcoyonol presented bacteriostatic (1.56-25.0 µg/mL) and bactericidal (25.0-400.0 µg/mL) effects against Gram-positive bacteria, disrupted the biofilm of S. aureus, and presented a synergistic effect after its combination with ß-lactams and aminoglycosides. The low cytotoxicity of netzahualcoyonol (Selectivity Index (SI) for S. aureus (2.56), S. saprophyticus (20.56), and Bacillus subtilis (1.28)) suggests a good security profile. Taken together, these results show that netzahualcoyonol is promising for the development of a new effective antibacterial agent.


Asunto(s)
Celastraceae , Salacia , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Bacterias Grampositivas , Antibacterianos/farmacología
3.
Artículo en Inglés | MEDLINE | ID: mdl-33681931

RESUMEN

INTRODUCTION: Neck circumference (NC) and anthropometric data of people living with HIV (PLWH) are correlated. METHODS: Socioeconomic, NC, body mass index (BMI), tricipital skinfold thickness (TSF), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), waist-hip ratio (WHR), waist-to-height ratio (WHtR), waist circumference (WC), and hip circumference (HC) data of 72 PLWH were correlated. RESULTS: Higher adiposity was observed in NC (40.3% [n=29]) and WC (31.9% [n=23]). Correlations between NC/BMI, NC/WC, NC/HC, NC/MAC, NC/MAMC, and NC/WHtR were significant. Increased NC (40.3%[n=29]) and WC (31.9 [n=23]) were associated with higher cardiometabolic risk. CONCLUSIONS: NC correlations are adequate for estimating cardiometabolic risk.


Asunto(s)
Adiposidad , Infecciones por VIH , Índice de Masa Corporal , Estudios Transversales , Infecciones por VIH/complicaciones , Humanos , Factores de Riesgo , Relación Cintura-Estatura , Relación Cintura-Cadera
4.
J Ethnopharmacol ; 266: 113423, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33007390

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Pristimerin is a triterpenoid considered the main component of Salacia crassifolia extracts. This terpene has shown promising antitumor, anti-inflammatory, and antimicrobial effects. Likewise, S. crassifolia has been used in traditional medicine to treat cancer and as an antimicrobial and anti-inflammatory agent. AIM OF THE STUDY: This study aimed to evaluate the antibacterial activity of the hexane extract of Salacia crassifolia roots (HER) and its isolate, pristimerin, against pathogenic bacteria. MATERIALS AND METHODS: First, we evaluated the spectrum of action of HER and pristimerin by the determination of the minimum inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC). Subsequently, we analyzed the time-kill curve of these plant-derived compounds against Staphylococcus aureus. Then, we examined their mode of action by three different assays: the crystal violet methodology, the release of intracellular material, and transmission electron microscopy methods (TEM). Finally, we evaluated the effect of HER and pristimerin on the pre-formed biofilm of S. aureus by the crystal violet assay, the synergistic effect by the checkerboard method, the cytotoxicity against Vero cells, and the in silico activity using the online software PASS. RESULTS: HER and pristimerin presented a narrow spectrum of action against Gram-positive bacteria (MIC 0.195-25 µg/mL), and their primary mode of action is the alteration of membrane permeability of S. aureus. Our results show that the compounds disrupted the pre-formed biofilm of S. aureus in a dose-dependent manner. Furthermore, HER and pristimerin presented a significant synergic effect after the combination with well-known antibiotics, which was associated with the ability of these phytomedicines to change membrane permeability. Regarding the cytotoxic effect, the selective index (SI) of HER ranged from 0.37 to 11.86, and the SI of pristimerin varied from 0.24 to 30.87, according to the bacteria tested. CONCLUSIONS: Overall, HER and pristimerin showed a promising antibacterial effect in vitro through the alteration of membrane permeability of S. aureus.


Asunto(s)
Antibacterianos/farmacología , Salacia/química , Staphylococcus aureus/efectos de los fármacos , Triterpenos/farmacología , Animales , Antibacterianos/aislamiento & purificación , Biopelículas/efectos de los fármacos , Chlorocebus aethiops , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Triterpenos Pentacíclicos , Raíces de Plantas , Infecciones Estafilocócicas/tratamiento farmacológico , Triterpenos/aislamiento & purificación , Células Vero
5.
Rev. Soc. Bras. Med. Trop ; 54: e0649-2020, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1155589

RESUMEN

Abstract INTRODUCTION: Neck circumference (NC) and anthropometric data of people living with HIV (PLWH) are correlated. METHODS: Socioeconomic, NC, body mass index (BMI), tricipital skinfold thickness (TSF), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), waist-hip ratio (WHR), waist-to-height ratio (WHtR), waist circumference (WC), and hip circumference (HC) data of 72 PLWH were correlated. RESULTS Higher adiposity was observed in NC (40.3% [n=29]) and WC (31.9% [n=23]). Correlations between NC/BMI, NC/WC, NC/HC, NC/MAC, NC/MAMC, and NC/WHtR were significant. Increased NC (40.3%[n=29]) and WC (31.9 [n=23]) were associated with higher cardiometabolic risk. CONCLUSIONS: NC correlations are adequate for estimating cardiometabolic risk.


Asunto(s)
Humanos , Infecciones por VIH/complicaciones , Adiposidad , Índice de Masa Corporal , Estudios Transversales , Factores de Riesgo , Relación Cintura-Cadera , Relación Cintura-Estatura
6.
Nutr. clín. diet. hosp ; 40(4): 83-90, 2020. tab
Artículo en Portugués | IBECS | ID: ibc-202462

RESUMEN

INTRODUÇÃO: O diabetes mellitus (DM) é uma condição metabólica de evolução crônica que pode resultar em complicações clínicas e prejuízos multidimensionais na qualidade de vida (QV) em dois pacientes. OBJETIVO: Comparar a QV, ou estado de saúde e consumo de fibras, entre pacientes com DM participantes (G1) e não participantes (G2) de consultorias de culinária. MÉTODOS: Estudo transversal realizado com voluntários com DM tipo II, de ambos os sexos. A QV foi endossada por meio da fermentação do WHOQOL-BREF, dois valores de forame voluntário ou estado emocional na escala B-PAID, e o consumo de fibra foi endossado para cabelos recordatórios de 24 horas. Os dados para o software de análise de cabelo ® Stataversão 13.0. RESULTADOS: Os participantes dos serviços de culinária relataram QV "boa" em 81,8% dos dois casos em detrimento de 18,2% dos participantes dos escritórios de culinária. Em relação ao consumo de fibras, o consumo médio foi de 24,6 g para ou G1 e 19,7g para ou G2 (p <0,001). Com a avaliação da escala B-PAID, observa-se prevalência de frequências de respostas como "nenhum problema" e "pequeno problema" para o ou G1, ou que caracterizam uma maior certeza de questões emocionais ligadas ao ou DM, no G2 no Há um maior número de respostas do tipo "é um problema moderado", "que problema sério" e "um problema sério" ou que caracteriza uma instabilidade emocional relacionada ao ou DM. CONCLUSÃO: Diabéticos participantes de consultorias gastronômicas relatam sobre QV, consumo de fibras alimentares e estado de saúde


INTRODUCTION: Diabetes mellitus is a metabolic disease of chronic evolution that can result in clinical complications and multidimensional damage to the emotional state and quality of life of patients. OBJECTIVE: To compare dietary fiber intake, emotional state, and quality of life of diabetics attending and not attending culinary workshops. METHODS: A descriptive observational study carried out in an outpatient clinic belonging to a public university of the Inconfidentes Region, Minas Gerais, with type 2 diabetes patients of both sexes. The evaluations of fiber intake, emotional state and quality of life were carried out through the application of the 24-hour recall, B-PAID scale and WHOQOLBREF, respectively. Data were analyzed by Stata® software, version 13.0. RESULTS: In total, 22 type 2 diabetic patients participated in this study allocated in two groups: group 1 (G1) participants of culinary workshops (n=11) and group 2 (G2) nonparticipants in culinary workshops (n=11). The average dietary fiber intake was 24.6g for G1 and 19.7g for G2 (p < 0.01). As for the emotional state evaluation score, it was observed that the participants of the culinary workshops obtained 11.7 points and non-participants 30.7 points (p < 0.01). Participants in culinary workshops reported "good" quality of life in 81.8% of cases to the detriment of 18.2% of non-participants in culinary workshops (p = 0.013). CONCLUSION: Diabetics attending the culinary workshops reported higher fiber intake, better emotional state and quality of life of diabetic patients


Asunto(s)
Humanos , Masculino , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Diabetes Mellitus/psicología , Calidad de Vida , Educación Alimentaria y Nutricional , Fibras de la Dieta , Dieta Saludable , Salud Mental
7.
Braz. J. Pharm. Sci. (Online) ; 56: e18474, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1249171

RESUMEN

Due to the increase of bacterial resistance, the search for new antibiotics is necessary and the medicinal plants represent its most important source. The aim of this study was to evaluate the antibacterial property of extract and fractions from Protium spruceanum leaves, against pathogenic bacteria. By means of diffusion and microdilution assays, the crude extract was active against the nine bacteria tested being the hydromethanolic fraction the most active. During phytochemical procedures, procyanidin (1) and catechin (2) were identified as the main antibacterial constituents of this fraction. In silico results obtained using PASSonline tool indicated 1 and 2 as having good potential to interact with different targets of currently used antibiotics. These results no indicated potential to none DNA effect and indicated the cell wall as mainly target. Electrophoresis result supported that had no DNA damage. Cell wall damage was confirmed by propidium iodide test that showed increased membrane permeability and by cell surface deformations observed in scanning electronic microscopy. The in vitro assays together with the in silico prediction results establish the potential of P. spruceanum as source of antibacterial compounds that acts on important bacterial targets. These results contribute to the development of natural substances against pathogenic bacteria and to discovery of new antibiotics.


Asunto(s)
Plantas Medicinales/efectos adversos , Técnicas In Vitro/métodos , Extractos Vegetales/análisis , Catequina , Antibacterianos/análisis , Simulación por Computador , Microscopía Electrónica de Rastreo/métodos , Hojas de la Planta/clasificación , Burseraceae/clasificación , Fitoquímicos
8.
Antiviral Res ; 168: 76-81, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31125633

RESUMEN

Mayaro virus (MAYV) is a sublethal arbovirus transmitted by mosquitoes with possible installation of an urban cycle in the Americas. Its infection causes disabling arthralgia, and still, there is no vaccine or treatment to it. We recently investigated nearly 600 compounds by molecular docking and identified epicatechin as a potent antiviral against MAYV. The root extract of Maytenus imbricata showed anti-MAYV activity and two isolated compounds from this plant were also evaluated in vitro. Proanthocyanidin (PAC), a dimer containing epicatechin, showed an effective concentration for 50% of the cells infected by MAYV (EC50) of 37.9 ±â€¯2.4 µM and a selectivity index (SI) above 40. PAC showed significant virucidal activity, inhibiting 100% of the virus proliferation (7 log units), and caused moderate effect during adsorption and virus internalization stage. However, PAC was unable to block the infection when only the cells were pretreated. It was observed a reduction in virus yields when adding PAC at different moments after infection. The set of results indicates that PAC binds to viral and non-cellular elements and may inactivate the MAYV. The inactivation occurs before infection or when the virus reaches the extracellular environment from the 2nd cycle of infection that could block its progression cell-to-cell or to tissues not yet infected.


Asunto(s)
Alphavirus/efectos de los fármacos , Antivirales/farmacología , Proantocianidinas/farmacología , Infecciones por Alphavirus/virología , Animales , Antivirales/química , Catequina/química , Catequina/farmacología , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Magnoliopsida/química , Estructura Molecular , Raíces de Plantas/química , Proantocianidinas/química , Células Vero , Acoplamiento Viral/efectos de los fármacos , Internalización del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos
9.
Artículo en Inglés | MEDLINE | ID: mdl-29473533

RESUMEN

BACKGROUND: The red propolis (RdProp) is a resin produced by Apis mellifera bees, which collect the reddish exudate on the surface of its botanic source, the species Dalbergia ecastophyllum, popularly known in Brazil as "rabo de bugio". Considered as the 13th type of Brazilian propolis, this resin has been gaining prominence due to its natural composition, rich in bioactive substances not found in other types of propolis. OBJECTIVE: This review aims to address the most important characteristics of RdProp, its botanical origin, the main constituents, its biological properties and the patents related to this natural product. METHOD: By means of the SciFinder, Google Patents, Patus® and Spacenet, scientific articles and patents involving the term "red propolis" were searched until August 2017. RESULTS: A number of biological properties, including antimicrobial, anti-inflammatory, antiparasitic, antitumor, antioxidant, metabolic and nutraceutical activities are attributed to RdProp, demonstrating the great potential of its use in the food, pharmaceutical and cosmetics industries. CONCLUSION: The available papers are associated to pharmacological potential of RdProp, but the molecular mechanisms or bioactive compounds responsible for each activity have not yet been fully elucidat ed. The RdProp patents currently found are directed to components for the pharmaceutical industry (EP2070543A1; WO2014186851A1; FR3006589A1; CN1775277A; CN105797149A; CN1879859A), cosmetic (JP6012138B2; JP2008247830A; JP6012138B2) and food (JP5478392B2; CN101380052A; WO2006038690A1).


Asunto(s)
Abejas/metabolismo , Dalbergia , Suplementos Dietéticos , Própolis/uso terapéutico , Animales , Antiinfecciosos/uso terapéutico , Antiinflamatorios/uso terapéutico , Antineoplásicos/uso terapéutico , Antioxidantes/uso terapéutico , Brasil , Suplementos Dietéticos/efectos adversos , Humanos , Legislación de Medicamentos , Patentes como Asunto , Própolis/efectos adversos , Própolis/biosíntesis
10.
Braz. J. Pharm. Sci. (Online) ; 53(3): e00251, 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-889402

RESUMEN

ABSTRACT The triterpene lupeol (1) and some of its esters are secondary metabolites produced by species of Celastraceae family, which have being associated with cytotoxic activity. We report herein the isolation of 1, the semi-synthesis of eight lupeol esters and the evaluation of their in vitro activity against nine strains of cancer cells. The reaction of carboxylic acids with 1 and DIC/DMAP was used to obtain lupeol stearate (2), lupeol palmitate (3) lupeol miristate (4), and the new esters lupeol laurate (5), lupeol caprate (6), lupeol caprilate (7), lupeol caproate (8) and lupeol 3',4'-dimethoxybenzoate (9), with high yields. Compounds 1-9 were identified using FT-IR, 1H, 13C-NMR, CHN analysis and XRD data and were tested in vitro for proliferation of human cancer cell activity. In these assays, lupeol was inactive (GI50> 250µg/mL) while lupeol esters 2 -4 and 7 - 9 showed a cytostatic effect. The XRD method was a suitable tool to determine the structure of lupeol and its esters in solid state. Compound 3 showed a selective growth inhibition effect on erythromyeloblastoid leukemia (K-562) cells in a concentration-dependent way. Lupeol esters 4 and 9 showed a selective cytostatic effect with low GI50 values representing promising prototypes for the development of new anticancer drugs.


Asunto(s)
Triterpenos/análisis , Celastraceae/clasificación , Productos Biológicos , Quimioprevención/estadística & datos numéricos
11.
Curr Drug Discov Technol ; 12(4): 229-39, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26416665

RESUMEN

In order to verify the chemical qualities of polar extract of Green Propolis produced in the State of Minas Gerais, Brazil, was analyzed by means of RP-HPLC, the concentration of eleven flavonoids, Artepillin C and p-coumaric acid were analyzed by means of RP-HPLC. Samples were collected in the months of February, March, May, July, September, and October, during a period of six years (2008 to 2013) and the results compared with purchased standards. Artepillin C was the main constituent (80-90%) found in all samples. Lower concentrations of p-coumaric acid, chrysin and kaempferide were observed in March, and of ricin and galangin in September. Respectively, these months correspond to the end of Summer and Spring period in Brazil. The variation in concentration of the analyzed constituents always occurred in the same month, during the entire six years of evaluation period. All thirteen constituents of Green Propolis were detected throughout the study period, and the average concentration of each one was similar in relation to the respective monthly collection period of each year. Due to similarities among chemical constituents of Green Propolis with those present in B. dracuncufolia, this plant was identified as being the principal source of Green Propolis.


Asunto(s)
Baccharis , Flavonoides/análisis , Própolis/química , Alimentos Funcionales , Estaciones del Año
12.
Molecules ; 16(12): 9939-56, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22134400

RESUMEN

Three compounds were isolated from Maytenus acanthophylla Reissek (Celastraceae): the pentacyclic triterpenes lup-20(29)-en-3ß-ol (lupeol, 1) and 3ß-lup-20(29)-en-3-yl acetate (2) and the carbohydrate 1,2,3,4,5,6-hexa-O-acetyldulcitol (3); lupeol was also isolated from Xylosma flexuosa. The compounds' structures were elucidated by spectroscopic and spectrometric analysis. Compound 1 acts as an energy transfer inhibitor, interacting with isolated CF1 bound to thylakoid membrane, and dulcitol hexaacetate 3 behaves as a Hill reaction inhibitor and as an uncoupler, as determined by polarography. Chlorophyll a (Chl a) fluorescence induction kinetics from the minimum yield F0 to the maximum yield F(M )provides information of the filling up from electrons coming from water to plastoquinone pool with reducing equivalents. In this paper we have examined the effects of compounds 1 and 3 on spinach leaf discs. Compound 1 induces the appearance of a K-band, which indicates that it inhibits the water splitting enzyme. In vivo assays measuring the fluorescence of chl a in P. ixocarpa leaves sprayed with compound 1, showed the appearance of the K-band and the PSII reaction centers was transformed to "heat sinks" or silent reaction centers unable to reduce Q(A). However, 3 also induced the appearance of a K band and a new band I appears in P. ixocarpa plants, therefore it inhibits at the water splitting enzyme complex and at the PQH2 site on b6f complex. Compounds 1 and 3 did not affect chlorophyll a fluorescence of L. perenne plants.


Asunto(s)
Galactitol/farmacología , Luz , Fotosíntesis/efectos de los fármacos , Fotosíntesis/efectos de la radiación , Triterpenos/farmacología , ATPasa de Ca(2+) y Mg(2+)/metabolismo , Clorofila/metabolismo , Clorofila A , Transporte de Electrón/efectos de los fármacos , Transporte de Electrón/efectos de la radiación , Fluorescencia , Galactitol/química , Cinética , Maytenus/química , Paraquat/metabolismo , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacología , Fosforilación/efectos de los fármacos , Fosforilación/efectos de la radiación , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/efectos de la radiación , Spinacia oleracea/efectos de los fármacos , Spinacia oleracea/metabolismo , Spinacia oleracea/efectos de la radiación , Tilacoides/efectos de los fármacos , Tilacoides/enzimología , Tilacoides/efectos de la radiación , Triterpenos/química
13.
Acta sci., Biol. sci ; 33(4): 437-443, Out.-Dec. 2011. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-868149

RESUMEN

The effect of 2-pyridinecarboxylic acid (picolinic acid) on trypanosomes of the subgenus Schizotrypanum isolated from the bat Phyllostomus hastatus was determined in this study. Picolinic acid, at 50 µg mL-1, inhibited epimastigote growth by 99% after 12 days incubation. In addition, trypomastigote motility decreased by 50% after 6h and completely after 24h in the presence of 50 µg mL-1 picolinic acid. The 50% cytotoxic concentration on HEp-2 cell line was 275 µg mL-1 after 4 days incubation. Altogether, these results indicate higher toxicity against trypanosomes. The inhibitory effect of picolinic acid on epimastigote growth can be partially reversed by nicotinic acid and L-tryptophan, suggesting a competitive inhibition. Furthermore, two anti-Trypanosoma (Schizotrypanum) cruzi drugs were also evaluated with regard to bat trypanosome growth. Benznidazole, at 50 µg mL-1, inhibited epimastigote growth by 90% after 12 days incubation. Nifurtimox, at the same concentration, caused 96% growth inhibition after four days incubation. Corroborating a previous study, bat trypanosomes are a good model for screening new trypanocidal compounds. Moreover, they can be used to study many biological processes common to human pathogenic trypanosomatids.


O efeito do ácido 2-piridinocarboxílico (ácido picolínico) sobre um tripanossoma do subgênero Schizotrypanum isolado do morcego Phyllostomus hastatus foi determinado neste estudo. O ácido picolínico, na concentração de 50 µg mL-1, inibiu 99% do crescimento de epimastigotas após 12 dias de incubação. Além disso, houve um decréscimo de 50 e 100% na mobilidade dos tripomastigotas após 6 e 24h, respectivamente, em presença de ácido picolínico na concentração de 50 µg mL-1. A concentração citotóxica 50% para células HEp-2 foi de 275 µg mL-1 após quatro dias de incubação. Esses resultados indicam maior toxicidade contra os tripanossomas. O efeito inibitório do ácido picolínico sobre o crescimento de epimastigotas pode ser parcialmente revertido por ácido nicotínico e L-triptofano, sugerindo inibição competitiva. Adicionalmente, o efeito de dois fármacos com atividade anti-Trypanosoma (Schizotrypanum) cruzi foi avaliado sobre o crescimento do tripanossoma de morcego. Benzonidazol, na concentração de 50 µg mL-1, inibiu 90% do crescimento de epimastigotas após 12 dias de incubação. Nifurtimox, na mesma concentração, causou 96% de inibição do crescimento após quatro dias de incubação. Corroborando trabalhos anteriores, tripanossomas de morcegos são bons modelos para seleção inicial de novos compostos tripanocidas. Além disso, eles podem ser utilizados para estudar vários processos biológicos comuns aos tripanossomatídeos patogênicos ao homem.


Asunto(s)
Animales , Tripanosomiasis , Quirópteros , Antiinfecciosos
14.
Molecules ; 14(2): 598-607, 2009 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-19214150

RESUMEN

Friedelin (1), 3beta-friedelinol (2), 28-hydroxyfriedelin (3), 16alpha-hydroxyfriedelin (4), 30-hydroxyfriedelin (5) and 16alpha,28-dihydroxyfriedelin (6) were isolated through fractionation of the hexane extract obtained from branches of Salacia elliptica. After a week in CDCl(3) solution, 16alpha-hydroxyfriedelin (4) reacted turning into 3-oxo-16-methylfriedel-16-ene (7). This is the first report of a dehydration followed by a Nametkin rearrangement of a pentacyclic triterpene in CDCl(3) solution occurring in the NMR tube. These seven pentacyclic triterpenes was identified through NMR spectroscopy and the stereochemistry of compound 4 and 7 was established by 2D NMR (NOESY) spectroscopy and mass spectrometry (GC-MS). It is also the first time that all the (13)C-NMR and 2D NMR spectral data are reported for compounds 4 and 7.


Asunto(s)
Espectroscopía de Resonancia Magnética , Triterpenos/química , Medicamentos Herbarios Chinos/química , Espectroscopía de Resonancia Magnética/métodos , Conformación Molecular , Estructura Molecular , Salacia/química , Estereoisomerismo
15.
Appl Radiat Isot ; 66(5): 561-4, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18191404

RESUMEN

Through instrumental neutron activation analysis (INAA) the elemental chemical composition of Salvinia auriculata and Ouro Preto city public water was determined. Elements Ce, Th, Cr, Hf, Sb, Sc, Rb, Fe, Zn, Co, Au, La and Br were quantified. High chromium concentration was determined in this plant. But, chromium was determined only in low concentrations in the water. The results indicate the great capacity of this plant to absorb and accumulate inorganic elements.


Asunto(s)
Monitoreo del Ambiente/métodos , Helechos/metabolismo , Análisis de Activación de Neutrones/instrumentación , Contaminantes Radiactivos del Agua/metabolismo , Estándares de Referencia
16.
Rev Inst Med Trop Sao Paulo ; 44(2): 109-12, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12048549

RESUMEN

Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S.) cruzi compounds.


Asunto(s)
Celastraceae/química , Triterpenos/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Pruebas de Sensibilidad Parasitaria , Triterpenos/aislamiento & purificación
17.
Rev. Inst. Med. Trop. Säo Paulo ; 44(2): 109-112, Mar.-Apr. 2002. tab
Artículo en Inglés | LILACS | ID: lil-308015

RESUMEN

Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S.) cruzi compounds


Asunto(s)
Animales , Triterpenos , Tripanocidas , Trypanosoma cruzi , Pruebas de Sensibilidad Parasitaria , Triterpenos
18.
Rev. bras. farmacogn ; 12(supl.1): 123-124, 2002. ilus, tab
Artículo en Portugués | LILACS | ID: lil-528781

RESUMEN

Folhas de Austroplenckia populnea (mangabarana, marmelinho do campo) foram submetidos a estudo fitoquímico. Do extrato hexânico foram isolados e identificados três triterpenos pentacíclicos e um sesquiterpeno agarofurânico inédito. Realizou-se testes de atividade antiespermatogência utilizando parte deste extrato. Os resultados mostraram uma redução significativa do número de espermatozóides no epidídimo.

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