Browsing by Autor "Efraín Salamanca"

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Active sesquiterpene lactones against Leishmania amazonensis and Leishmania braziliensis
(Taylor & Francis, 2016) A Sosa; Susana Amaya; Efraín Salamanca; Miguel Gilabert; Alicia Bardón; Alberto Giménez; Nancy Vera; Susana Borkosky
Seventeen sesquiterpene lactones (SLs) isolated from five species of the tribe Vernonieae were evaluated for their in vitro activity against promastigotes of Leishmania amazonensis and Leishmania braziliensis. Additionally, a quantitative structure activity relationship has been made, since all these natural compounds were found to have potent to mild antileishmanial properties. The most active compounds against L. braziliensis were 16 and 17 (IC50 values 1.45 and 1.34 μM, respectively), followed by compound 15 with IC50 value of 1.60 μM against L. amazonensis. The three glaucolide-type SLs (4-6) were the least active against both parasites. The computational study allowed us to establish that lipophilicity and polarisability play an important role in the antiparasitic activity. This is the first report of the known germacradiendiolides 16 and 17 from Elephantopus mollis. The activity data of the compounds 1-17 assayed against Leishmania parasites are reported here for the first time.
Antibacterial and leishmanicidal activity of Bolivian propolis
(Oxford University Press, 2016) Nélida Nina; Beatriz Lima; Gabriela E. Feresin; A. Giménez; Efraín Salamanca; Guillermo Schmeda‐Hirschmann
Propolis is used in Bolivia as an antimicrobial agent. Bolivian propolis from the main production areas was assessed for antibacterial and leishmanicidal effect and the results were compared with the propolis chemical composition. The active antibacterial propolis samples were phenolic-rich while those containing mainly triterpenes were devoid of activity or weakly active. A similar picture was obtained for the effect on Leishmania, with better effect for the phenolic-rich samples. As propolis is used for the same purposes regardless of the production area and composition, our findings indicate the need for the standardization of this natural product as antimicrobial.
Antileishmanial metabolites from Lantana balansae
(Springer Science+Business Media, 2016) Eliana M. Maldonado; Efraín Salamanca; Alberto Giménez; Olov Sterner
Eleven compounds, 12-oxo-phytodienoic acid (1), persicogenin (2), eriodictyol 3′,4′,7-trimethyl ether (3), phytol (4), spathulenol (5), 4-hydroxycinnamic acid (6), onopordin (7), 5,8,4′-trihydroxy-7,3′-dimethoxyflavone (8), quercetin (9), jaceosidin (10), and 8-hydroxyluteolin (11), were isolated from an ethanol extract of Lantana balansae Briq., Verbenaceae, that was found to possess antileishmanial activity. The structures of the compounds were determined by NMR spectroscopy and HR mass spectrometry, and 1, 2, 3, 7, 8 and 9 were investigated for antiprotozoal activity toward promastigotes of Leishmania amazonensis and Leishmania braziliensis. Compound 1 was shown to be the most potent, with the IC50 values 2.0 μM toward L. amazonensis and 0.68 μM toward L. braziliensis, although less potent than the positive control Amphotericin B. All compounds have been reported previously, but this is the first report of the isolation of a cyclopentenone fatty acid (1) and flavanones (2 and 3) from a Lantana species.
Antileishmanial metabolites from Trixis antimenorrhoea
(Elsevier BV, 2014) Eliana M. Maldonado; Efraín Salamanca; Alberto Giménez; Gloria Saavedra; Olov Sterner
Antiparasitic activity of two Brazilian plants: Eugenia mattosii and Marlierea eugeniopsoides
(Taylor & Francis, 2020) Giovana Vechi; Adrielli Tenfen; Efraín Salamanca; Alberto Giménez; Valdir Cechinel Filho
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.
Antiparasitic Metabolites from Hyptis brevipes, a Tacana Medicinal Plant
(SAGE Publishing, 2019) Ivan Limachi; Claudia Condo; Camila Palma; Nélida Nina; Efraín Salamanca; Juan C. Ticona; Enrique Udaeta; Ninoska Flores; Alcides Serato; Natalio Marupa
A bioassay screening against protozoa parasites of several Tacana medicinal plants gave Hyptis brevipes (Id'ene eidhue), traditionally used as decoction for intestinal parasites, as the most active extract. In this work we did a bioguided isolation of active constituents found in leaves. Structure elucidation was carried out by NMR spectroscopy and MS spectrometry analyses. Active constituents showed differentiated activity towards Giardia lamblia, Trypanosoma cruzi, several Leishmania strains, Plasmodium falciparum and cytotoxicity against HeLa cells. Brevipolide H (1) was the less cytotoxic and best antiparasitic, while the catechol derivative (2) the most active and cytotoxic.
Avaliação biológica de híbridos pirazolino-aminopirimidinas como protótipos com potencial antiparasitário para o tratamento da Leishmaniose
(2025) Karla Seniuk Alferi; Efraín Salamanca; Alberto Giménez; Fátima de Campos Buzzi
As Doenças Tropicais Negligenciadas (DTNs) compreendem um grupo de enfermidades infecciosas que afetam principalmente populações em situação de vulnerabilidade socioeconômica em regiões tropicais e subtropicais. Apesar de sua elevada prevalência e impacto na saúde global, ainda recebem investimentos limitados em pesquisa e desenvolvimento de novos fármacos, o que contribui para a escassez de terapias eficazes, seguras e acessíveis. Nesse cenário, compostos heterocíclicos surgem como alternativas promissoras, em virtude de sua versatilidade estrutural, potencial bioativo e ampla aplicabilidade farmacológica. Estudos prévios do grupo de pesquisa em Química Farmacêutica avaliaram uma série de aminopirimidinas frente a protozoários como Leishmania e Giardia lamblia que apresentaram atividade antiparasitária relevante e resultados biológicos promissores. Entre as moléculas avaliadas, as que continham os substituintes metil e dimetilamino foram as mais ativas. A partir desses resultados, e considerando os medicamentos atualmente disponíveis para o tratamento da leishmaniose, como o isotionato de pentamidina, planejaram-se novas moléculas mantendo os substituintes mais ativos, visando aprimorar sua eficácia antiparasitária e contribuir para o desenvolvimento de candidatos a fármacos mais eficazes e com menores efeitos colaterais. Assim, este estudo teve como objetivo avaliar a atividade biológica de híbridos pirazolino-aminopirimidinas sintetizados quanto ao seu potencial antiparasitário. Inicialmente, foram sintetizadas duas chalconas substituídas por meio de condensação aldólica clássica: (2E)-3-(4-metilfenil)-1-fenilprop-2-en-1-ona (CHM), obtida a partir da reação entre acetofenona (0,025 mmol) e tolualdeído (0,062 mmol) em etanol sob agitação magnética, e (2E)-3-[4-(dimetilamino)fenil]-1-fenilprop-2-en-1-ona (CHNM), obtida pela reação entre acetofenona (0,025 mmol) e dimetilaminobenzaldeído (0,062 mmol) em etanol sob agitação magnética. Após isso, as chalconas obtidas foram empregadas como precursores para a obtenção de derivados contendo o grupo carboximidamida. A chalcona CHM (2,2493 mmol) foi submetida à reação em refluxo com cloridrato de aminoguanidina (4,4986 mmol) em etanol, assim como, a chalcona CHNM (1,9894 mmol) reagiu sob as mesmas condições com cloridrato de aminoguanidina (3,9788 mmol). Os produtos obtidos foram isolados, purificados e caracterizados por RMN¹H, RMN¹³C, IV, espectrometria de massas e ponto de fusão, confirmando a formação dos compostos desejados. Posteriormente, os derivados sintetizados foram avaliados quanto à atividade antiparasitária, utilizando o método colorimétrico XTT para promastigotas de Leishmania spp. e epimastigotas de Trypanosoma cruzi, e o método fluorométrico com Resazurina para trofozoítos de Giardia lamblia, além da avaliação de citotoxicidade em macrófagos RAW. Foram obtidas duas moléculas caracterizadas como híbridos pirazolino-aminopirimidinas, a 4-(4-metilfenil)-2-[3-(fenil)-5-(4-metilfenil)-4,5-dihidro-1H-pirazol-1-il]-6-(fenil)-pirimidina (PZN-P1) com rendimento de 39% e 4-[4-(dimetilamino)-fenil]-2-[3-(fenil)-5-[4-(dimetilamino)-fenil]-4,5-dihydro-1H-pyrazol-1-il]-6-(fenil)-pirimidina (PZNM) com rendimento de 28,4%. Os resultados da avaliação biológica dos compostos demonstraram que a molécula PZN-P1 apresentou atividade moderada contra Leishmania amazonensis (CI50 = 80,2 ± 8,1 µg/mL) e Leishmania braziliensis (CI50 = 79,1 ± 1 µg/mL), enquanto PZNM não demonstrou efeito significativo (CI50 > 100 µg/mL). Para Trypanosoma cruzi e Giardia lamblia, ambos os híbridos foram inativos (CI50 > 100 e > 200 µg/mL, respectivamente), além de apresentarem baixa citotoxicidade em macrófagos RAW (CI50 > 100 µg/mL). Em comparação com as aminopirimidinas previamente avaliadas (AMM e AMNM), os compostos híbridos foram menos potentes, sugerindo que a presença do núcleo pirazolina pode reduzir a eficácia antiparasitária. Os achados indicam que os híbridos sintetizados ainda demandam otimizações estruturais, mas reforçam o potencial dos derivados heterocíclicos como protótipos para o desenvolvimento de novos agentes antiparasitários.
Benzochromenes from the roots of Bourreria pulchra
(Elsevier BV, 2009) Gilda J. Erosa-Rejón; Alejandro Yam-Puc; Manuel Jesús Chan-Bacab; Alberto Giménez-Turbax; Efraín Salamanca; Luis M. Peña-Rodrı́guez; Olov Sterner
Chemical composition of essential oils of Piper jacquemontianum and Piper variabile from Guatemala and bioactivity of the dichloromethane and methanol extracts
(Springer Science+Business Media, 2011) Sully M. Cruz; Armando Cáceres; Luis E. Álvarez; Jorge Alexander Diaz Morales; Miriam Anders Apel; Amélia Teresinha Henriques; Efraín Salamanca; Alberto Giménez; Yelkaira Vásquez; Mahabir P. Gupta
The essential oils from two native species from Guatemala were studied for their chemical composition and the dichloromethane and methanol extracts for their biological activity. A GC-MS analysis of the essential oil from Piper jacquemontianum Kunth, Piperaceae, showed 34 constituents, consisting mainly of linalool (69.4%), while Piper variabile C. DC. essential oil had 36 constituents, camphor (28.4%), camphene (16.6%) and limonene (13.9%) being the major components. Dichloromethane extracts of both species were cytotoxic against MCF-7, H-460 and SF-268 cell lines (<7 µg/mL). Dichloromethane extract of P. jacquemontianum was slightly active against bacteria (0.5 mg/mL), was active against promastigotes of Leishmania (20.4-61.0 µg/mL), and epimastigotes of Trypanosoma cruzi (51.9 µg/mL). The methanol extract of P. variabile showed antimalarial activity against Plasmodium falciparum F32 (4.5 µg/mL), and the dichloromethane extract against Leishmania (55.8-76.3 µg/mL) and T. cruzi (45.8 µg/mL). None of the extracts from the two species was active against Aedes aegypti larvae and Artemia salina nauplii.
Drimanes from Drimys brasiliensis with leishmanicidal and antimalarial activity
(Instituto Oswaldo Cruz, Ministério da Saúde, 2013) Vanessa D. Claudino; Kesia Caroline da Silva; Valdir Cechinel Filho; Rosendo A. Yunes; Franco Delle Monachè; Alberto Giménez; Efraín Salamanca; David Gutierrez-Yapu; Ângela Malheiros
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.
Estandarizacion de un metodo fluorometrico sobre trofozoitos de giardia lamblia
(2015) Claudia Condo Montero; Efraín Salamanca; Ninoska Flores; Alberto Giménez Turba
ESTUDIO FITOQUÍMICO DE LAS HOJAS DE BOWDICHIA VIRGILIOIDES
(Universidad Autónoma del Estado de México, 2006) Juan C. Ticona; David Gutiérrez; Efraín Salamanca; Grace Ruiz; Crispín Paredes; Enrique Udaeta; Nayra Rodríguez; Gabriel García; Isabel López; A. Jiménez
"Bowdichia virgilioides, es una planta medicinal utilizada por la etnia Tacana, las hojas de este árbol fueron colectadas, en época seca, en la Prov. Abel Iturralde, Bolivia. Las hojas secas y pulverizadas fueron sometidas a maceración con diclorometano y el extracto crudo no presento actividad antipalúdica a dosis de 10μg/mL, frente a Plasmodium falciparum (cepa F32, sensible a la cloroquina). Estudios cromatográficos del extracto crudo y análisis espectroscópicos de las sustancias aisladas nos han permitido identificar: Lupeol (1), Lupenona (2), β-sitosterol (3), estigmasterol (4) y β-amirina (5), como los principales componentes triterpénicos acompañados de ácidos grasos no identificados."
ESTUDIOS QUÍMICOS, BIOLÓGICOS Y FARMACOLÓGICOS DE Galipea longiflora, KRAUSE
(Universidad Autónoma del Estado de México, 2005) Alberto Giménez; J. Antonio Avila; Grace Ruiz; Magali Paz; Enrique Udaeta; Juan C. Ticona; Efraín Salamanca; Crispín Paredes; Norka Rodríguez; Katia Quints
"La especie medicinal Galipea longiflora (Evanta) es utilizada por las etnias amazónicas: Tacana, Mosetene y Tsimane, como antiparasitario. Los alcaloides totales de esta especie vegetal serán centro de estudios clínicos como tratamiento alternativo para la leishmaniasis cutánea. Nuestros estudios detallan el aislamiento y caracterización de alcaloides quinolínicos, de la corteza y hojas, todos con actividad leishmanicida evaluada sobre promastigotes de: L. amazonensis, L. braziliensis, L. donovani y L. chagasi. Mediante modelos toxico cinéticos, se ha determinado la toxicidad aguda, subcrónica y parámetros fármaco-cinéticos, para el extracto crudo, en modelo murino. Se establecen las condiciones para el cultivo semi-continuo, in vitro, de células de Evanta."
Frecuencia y distribución de enteroparásitos en área rural del departamento de La Paz
(2022) María Del Rosario Chávez Padilla; Efraín Salamanca; María Luz Soto Sánchez
enfermedades parasitarias representan un problema de salud pública debido a su alta prevalencia por todo el mundo sobre todo en países en desarrollo, especialmente en áreas rurales y Bolivia no es la excepción. Objetivo. El presente estudio tuvo el objetivo de determinar la frecuencia y distribución de enteroparásitos en 8 municipios rurales del departamento de La Paz durante el periodo de agosto a septiembre de 2014. Materiales y Métodos. El trabajo es un estudio tipo transversal-descriptivo con un universo de trabajo de 1238 muestras de heces fecales conservadas con formol, las cuales fueron enviadas por el equipo médico de SUYANA (organización no gubernamental sin fines de lucro) a los laboratorios del Instituto SELADIS (Servicios de Laboratorio de Diagnóstico e Investigación en Salud). Resultados. Se realizaron estudios coproparasitológicos directos de cada una de las muestras y la observación microscópica dio los siguientes resultados. Se evidencio la presencia de enteroparásitos en 89,5% de la población estudiada, de los cuales 97,2% representan protozoarios tales como B. hominis, E. coli (protoozoos comensales) y G. lamblia (protozoo intestinal patógeno) los cuales estarían como los de mayor distribución, por otro lado el 2.8% de la población total corresponden a helmintos donde H. nana tiene una distribución de 1,8%, A. lumbricoides 0,7% y T. trichiura, S. stercoralis, Uncinarias estarían en el 0,1% de la población. También se pudo evidenciar que la mayor distribución de enteroparásitos estaría entre 1-10 años de edad (37,4%). Finalmente se evidencio que de las 8 poblaciones de estudio Charazani, Calacoto, Comanche presentarían mayor distribución de enteroparásitos (10-11 parásitos). Conclusión. Se evidencio que casi el 90% de la población en estudio, presentarían parásitos intestinales, con un claro predominio de los protozoarios sobre los helmintos. Esta información epidemiológica servirá de apoyo para mejorar los programas de salud en estas poblaciones. Palabras clave: Enteroparásitos, Protozoarios, Helmintos, poliparasitismo, área rural.
Leishmaniasis in the major endemic region of Plurinational State of Bolivia: Species identification, phylogeography and drug susceptibility implications
(Elsevier BV, 2017) Pablo Bilbao-Ramos; María Auxiliadora Dea‐Ayuela; Oscar Victor Cardenas-Alegría; Efraín Salamanca; José Antonio Santalla-Vargas; C. Benito; Ninoska Flores; F. Bolás‐Fernández
Leishmanicidal Activity and Immunomodulatory Effect of a Mixture of Lupenone and β-Caryophyllene Oxide
(Springer Science+Business Media, 2021) Glendy Polanco-Hernández; Alberto Giménez-Turba; Efraín Salamanca; Giulia Getti; Rajeev Rai; Karla Y. Acosta-Viana; Víctor Ermilo Arana‐Argáez; Julio César Torres‐Romero; Karla Fernández-Martín; Maira Rubí Segura Campos
Leishmanicidal and cytotoxic activity from plants used in Tacana traditional medicine (Bolivia)
(Elsevier BV, 2018) Diandra Arévalo-Lopéz; Nélida Nina; Juan C. Ticona; Ivan Limachi; Efraín Salamanca; Enrique Udaeta; Crispín Paredes; Boris Espinoza; Alcides Serato; David Garnica
Microwave-Assisted Semisynthesis and Leishmanicidal Activity of Some Phenolic Constituents from Lichens
(Multidisciplinary Digital Publishing Institute, 2023) Grover Castañeta; Rodrigo Villagomez; Efraín Salamanca; Pamela Canaviri-Paz; José A. Bravo; José L. Vila; Daniela Bárcenas-Pérez; José Cheel; Beatriz Sepúlveda; Alberto Giménez
Leishmaniasis is considered one of the most untreated tropical diseases in the world. In this study, we investigated the in vitro leishmanicidal activity and cytotoxicity of various isolated lichen substances, including atranorin (1), usnic acid (2), gyrophoric acid (3), salazinic acid (4), galbinic acid (5), and parietin (6), and some semi-synthetic imine derivatives of usnic acid (7, 8, 9) and atranorin (10, 11, 12, 13). Imine condensation reactions with hydrazine and several amines were assisted by microwave heating, an efficient and eco-friendly energy source. The most interesting result was obtained for compound 2, which has high leishmanicidal activity but also high cytotoxicity. This cytotoxicity was mitigated in its derivative, 9, with better selectivity and high antileishmanic activity. This result may indicate that the usnic acid derivative (9) obtained using condensation with two cyclohexylamine groups is a promising lead compound for the discovery of new semisynthetic antiparasitic drugs.
Prenylated Acylphloroglucinols with Leishmanicidal Activity from the Fern Elaphoglossum lindbergii
(American Chemical Society, 2015) Cecilia Socolsky; Efraín Salamanca; Alberto Giménez; Susana Borkosky; Alicia Bardón
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.
Preparations from Campomanesia reitziana reduce the gastrointestinal motility and castor oil‐induced diarrhea in a non‐opioid and non‐dopaminergic pathway in mice and display antimicrobial activity in vitro
(Wiley, 2021) Marihá Mariott; Luísa Nathália Bolda Mariano; Thaise Boeing; Camile Cecconi Cechinel‐Zanchett; Efraín Salamanca; Alexandre Bella Cruz; Alberto Giménez; Valdir Cechinel Filho; Luísa Mota da Silva
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.