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1.
J Nat Prod ; 87(3): 456-469, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38395785

RESUMEN

The phytochemical investigation of the leaves and trunk bark of a specimen of Ocotea aciphylla collected in the southern portion of the Amazon forest led to the isolation of an oxabicyclo[3.2.2]nonane-type neolignan and 15 bicyclo[3.2.1]octanoid neolignans, 14 of which are unreported compounds (2-15), including one with an unusual oxidation pattern of the side chain at C-1' and two rare 7.1',8.3'-connected bicyclo[3.2.1]octanoid derivatives. Their structures and relative configurations were determined by extensive spectrometric analysis based on 1D- and 2D-NMR spectroscopy and HRESIMS data, while their absolute configurations were unambiguously assigned using electronic and vibrational circular dichroism data assisted by density functional theory calculations. Additionally, known sesquiterpenes, phenylpropanoids, and phytosterols were also isolated.


Asunto(s)
Lignanos , Ocotea , Lignanos/química , Ocotea/química , Alcanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Dicroismo Circular
2.
Bioorg Med Chem ; 32: 115994, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33477019

RESUMEN

The styrylpyrone dehydrogoniothalamin (1) and two of its dimers (2 and 3) were isolated from the leaves of Aniba heringeri (Lauraceae). Compound 3 is new, while 1 and 2 are being reported for the first time in this species. Structures were determined by 1D- and 2D-NMR spectroscopy, mass spectrometry, and optical rotation data. Cytotoxic effects and selectivity indices were evaluated in five neoplastic cell lines-PC-3 (prostate), 786-0 (renal), HT-29 (colon), MCF-7, and MDA-MB-231 (breast)-and a non-neoplastic cell line, (NIH/3T3, murine fibroblast). Compound 1 inhibited cell growth by 50% (GI50) at concentrations in the 90.4-175.7 µM range, while 2 proved active against MCF-7 and MDA-MB-231 breast cells (GI50 = 12.24, and 34.22 µM, respectively). Compound 3 showed strong cytotoxicity (GI50 = 4.4 µM) against MDA-MB-231 (an established basal triple-negative breast carcinoma (TNBC) cell line), with a high selective index of 35. This compound was subsequently evaluated for apoptosis induction in MDA-MB-231 cells, using GI50 and 50% lethal concentrations (LC50). Flow cytometry analysis showed that at LC50 compound 3 induced cell death with phosphatidylserine externalization and caspase-3 activation. Apoptotic genes were measured by RT-qPCR, revealing an upregulation of BAX, with an increase in expression of the BAX/BCL2 ratio in treated cells. Fluorescence microscopy disclosed morphological changes related to apoptosis. Overall, these findings showed compound 3 to be a promising prototype against TNBC cells that tend to respond poorly to conventional therapies.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Lauraceae/química , Piranos/farmacología , Estirenos/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Estructura Molecular , Piranos/química , Piranos/aislamiento & purificación , Relación Estructura-Actividad , Estirenos/química , Estirenos/aislamiento & purificación , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología
3.
Molecules ; 25(14)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708062

RESUMEN

Foodborne pathogens are a real public health concern in an escalating antimicrobial resistance scenario. Natural products represent a promising source of bioactive molecules, and essential oils have attracted much attention due to their myriad of biological properties, including antibacterial activities. In this context, essential oils obtained from the leaves of Chromolaena squalida, Campomanesia sessiliflora, Myrsine guianensis, Matayba guianensis, Siparuna guianensis, Ocotea minarum and Endlicheria paniculata-species from the Cerrado biome of Midwest Brazil-were extracted and evaluated for their antibacterial activity against a panel of four standard and three clinical multidrug-resistant bacterial strains. All tested oils showed moderate to good activity against at least four bacterial strains, including Salmonella Typhi and oxacillin-resistant Staphylococcus. The essential oils from C. squalida, C. sessiliflora, My. guianensis and Ma. guianensis showed strong inhibition of clinical Staphylococcus strains, which cause bovine mastitis and are related to milk-borne diseases. Their chemical profiles were investigated by gas chromatography coupled to mass spectrometry (GC/MS), which revealed a predominance of mono- and sesquiterpene hydrocarbons, some of which with well-known antimicrobial properties. The essential oil from Cerrado plants proved active against resistant Gram-positive and Gram-negative bacteria, revealing their potentialities for the development of new alternative agents to prevent the spreading of resistant bacterial contamination.


Asunto(s)
Antibacterianos/química , Aceites Volátiles/química , Extractos Vegetales/química , Hojas de la Planta/química , Aceites de Plantas/química , Tracheophyta/química , Animales , Antibacterianos/farmacología , Brasil , Bovinos , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Femenino , Microbiología de Alimentos , Cromatografía de Gases y Espectrometría de Masas , Mastitis Bovina/microbiología , Pruebas de Sensibilidad Microbiana , Leche/microbiología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Aceites de Plantas/farmacología , Salmonella typhi/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos
4.
Molecules ; 25(14)2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32664233

RESUMEN

The chemical investigation of the roots and stems of Combretum laxum yielded a new dihydrostilbene derivative, 4'-hydroxy-3,3',4-trimethoxy-5-(3,4,5-trimethoxyphenoxy)-bibenzyl (1), two phenanthrenes (2-3), and three dihydrophenanthrenes (4-6), along with one lignan, three triterpenoids, one aurone, one flavone, one naphthoquinone, and two benzoic acid derivatives. Their structures were determined by 1D and 2D nuclear magnetic resonance (NMR) spectroscopic techniques and/or mass spectrometry data. The occurrence of dihydrostilbenoid, phenanthrene and dihydrophenanthrene derivatives is unprecedented in a Combretum species native to the American continent. 2,7-Dihydroxy-4,6-dimethoxyphenanthrene, 2,6-dihydroxy-4,7-dimethoxy-9,10-dihydrophenanthrene and 5-O-methyl apigenin are novel findings in the Combretaceae, as is the isolation of compounds belonging to the chemical classes of aurones and naphthoquinones, while (+)-syringaresinol is reported for the first time in the genus Combretum. Compounds 1-6 were also evaluated for their in vitro cytotoxicity against five human cancer cell lines, and radical-scavenging ability against 1,1-diphenyl-2-picryl-hydrazyl (DPPH). 6-Methoxycoelonin (4) was the most cytotoxic against melanoma cells (IC50 2.59 ± 0.11 µM), with a high selectivity index compared with its toxicity against nontumor mammalian cells (SI 25.1). Callosin (6), despite exhibiting the strongest DPPH-scavenging activity (IC50 17.7 ± 0.3 µM), proved marginally inhibitory to the five cancer cell lines tested, indicating that, at least for these cells, antioxidant potential is unrelated to antiproliferative activity.


Asunto(s)
Combretum/química , Dihidrostilbenoides/farmacología , Fenantrenos/farmacología , Extractos Vegetales/farmacología , Animales , Antioxidantes/fisiología , Apigenina/farmacología , Compuestos de Bifenilo/farmacología , Línea Celular , Línea Celular Tumoral , Chlorocebus aethiops , Combretaceae/química , Humanos , Células MCF-7 , Espectroscopía de Resonancia Magnética/métodos , Melanoma/tratamiento farmacológico , Picratos/farmacología , Células Vero
5.
Mem Inst Oswaldo Cruz ; 0: 0, 2016 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-27333366

RESUMEN

A total of 36 ethanol extracts from different anatomical parts of 27 plant species (18 families), native to the Pantanal and Cerrado biomes in Midwest Brazil, was assessed for their effect against Aedes aegypti larvae, the vector of dengue, hemorrhagic dengue, Zika and chikungunya fevers. Only the extract obtained from seeds of Guarea kunthiana (Meliaceae) proved active (LC50 = 169.93 µg/mL). A bioassay-guided investigation of this extract led to the isolation and identification of melianodiol, a protolimonoid, as the active constituent (LC50 = 14.44 mg/mL). Meliantriol, which was also obtained from the bioactive fraction, was nevertheless devoid of any larval toxicity, even at the highest concentration tested (LC50 > 100.0 mg/mL). These results indicate that the larvicidal activity of melianodiol stems from the presence of the carbonyl moiety at C-3 in the 21,23-epoxy-21,24,25-trihydroxy-tirucall-7-ene-type skeleton. The structures of both protolimonoids were established on the basis of spectral methods (1H and 13C NMR and MS). This is the first report on the toxicity of melianodiol against Ae. aegypti larvae. Based on the results, melianodiol can be regarded as a potential candidate for use as an ecologically sound biocontrol agent for reducing the larval population of this vector.


Asunto(s)
Aedes , Agentes de Control Biológico , Insecticidas/farmacología , Larva , Meliaceae/química , Extractos Vegetales/farmacología , Triterpenos , Animales , Brasil , Fiebre Chikungunya/prevención & control , Dengue/prevención & control , Insecticidas/química , Control de Mosquitos/métodos , Extractos Vegetales/química , Infección por el Virus Zika/prevención & control
6.
Bioorg Med Chem Lett ; 24(5): 1358-61, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24507920

RESUMEN

A new cytotoxic ß-carboline alkaloid, 1-methyl-3-(2-hydroxypropan-2-yl)-2-(5-methoxy-9H-ß-carbolin-1-yl)-cyclopentanol (1), was isolated from roots of Galianthe thalictroides, together with the alkaloid 1-(hydroxymethyl)-3-(2-hydroxypropan-2-yl)-2-(5-methoxy-9H-ß-carbolin-1-yl)-cyclopentanol (2), the anthraquinones 1-methyl-alizarin and morindaparvin-A, the coumarin scopoletin, homovanillic alcohol, (-)-epicatechin, and the steroids stigmast-4-en-3-one, 4,22-stigmastadien-3-one, campest-4-en-3-one, stigmast-4-en-3,6-dione, 6-ß-hydroxy-stigmast-4-en-3-one, stigmasterol, campesterol, ß-sitosterol, and ß-sitosterol-3-O-ß-D-glucopyranoside. Among the previously known compounds, homovanillic alcohol is a novel finding in Rubiaceae, while 1-methyl-alizarin, morindaparvin-A, scopoletin, stigmast-4-en-3-one, 4,22-stigmastadien-3-one, campest-4-en-3-one, stigmast-4-en-3,6-dione, and 6-ß-hydroxy-stigmast-4-en-3-one is reported for the first time in the genus Galianthe. The cytotoxic ß-carboline alkaloids 1 and 2 exhibited potent antitopoisomerase I and IIα activities and strong evidence is provided for their action as topoisomerase IIα poisons and redox-independent inhibitors.


Asunto(s)
Alcaloides/química , Antígenos de Neoplasias/metabolismo , ADN-Topoisomerasas de Tipo II/metabolismo , ADN-Topoisomerasas de Tipo I/metabolismo , Proteínas de Unión al ADN/metabolismo , Lactosa/análogos & derivados , Oligopéptidos/química , Rubiaceae/química , Inhibidores de Topoisomerasa/química , Alcaloides/aislamiento & purificación , Alcaloides/toxicidad , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN-Topoisomerasas de Tipo I/química , Proteínas de Unión al ADN/antagonistas & inhibidores , Humanos , Lactosa/síntesis química , Lactosa/química , Lactosa/farmacocinética , Células MCF-7 , Ratones , Oligopéptidos/síntesis química , Oligopéptidos/farmacocinética , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Rubiaceae/metabolismo , Inhibidores de Topoisomerasa/aislamiento & purificación , Inhibidores de Topoisomerasa/toxicidad
7.
Molecules ; 20(1): 111-26, 2014 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-25546624

RESUMEN

Chemical investigation of Guarea kunthiana fruits, guided by their effect on the reproductive cycle of engorged females of the cattle tick Rhipicephalus (Boophilus) microplus-a major economic problem to the livestock industry worldwide-led to isolation of 3ß-O-tigloylmelianol, a new protolimonoid, from the bioactive hexane phase obtained by partitioning the crude ethanol extract. An adult immersion test was performed. The compound strongly inhibited egg-laying and hatchability (99.2% effectiveness at a 0.01% concentration). Melianone, isolated from the same phase, yielded unremarkable results in the adult immersion test. From the dichloromethane phase, melianol, melianodiol, meliantriol, and a new protolimonoid, 3ß-O-tigloylmeliantriol, were isolated, all of which, in the same manner as melianone, exhibited unremarkable results in the test. The structures of new and known compounds were mostly established by 1D- and 2D-NMR analyses and mass spectrometry data. This is the first report on the bioactivity of protolimonoids on the reproductive cycle of engorged females of R. (B.) microplus. 3ß-O-Tigloylmelianol proved a promising candidate for the development of a biocontrol agent against the cattle tick investigated, as an alternative to environmentally hazardous synthetic acaricides.


Asunto(s)
Acaricidas/farmacología , Enfermedades de los Bovinos/parasitología , Bovinos/psicología , Limoninas/farmacología , Meliaceae/química , Rhipicephalus/efectos de los fármacos , Animales , Femenino , Limoninas/aislamiento & purificación , Espectroscopía de Protones por Resonancia Magnética , Rhipicephalus/patogenicidad , Espectrometría de Masa por Ionización de Electrospray
8.
Front Pharmacol ; 15: 1390715, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055497

RESUMEN

Introduction: Leishmaniasis, a neglected tropical parasitic disease, is regarded as a major public health problem worldwide. The first-line drugs for leishmaniasis suffer from limitations related to toxicity and the development of resistance in certain parasitic strains. Therefore, the discovery of alternative treatments for leishmaniasis is imperative, and natural products represent a valuable source of potential therapeutic agents. Methods: The present study aimed at finding new potential antileishmanial agents from the aerial parts of the medicinal plant Momordica charantia. This study was based on bioassay-guided fractionation of the M. charantia extract against promastigotes and amastigotes of Leishmania (Leishmania) amazonensis. The cytotoxicity of the extract, fractions, and isolated compounds were evaluated against peritoneal murine macrophages by employing the MTT assay for assessing cell metabolic activity. Results: Antileishmanial assay-guided fractionation of the M. charantia extract led to the bioactive cucurbitacin-enriched fraction and the isolation of four bioactive cucurbitacin-type triterpenoids, which exhibited significant antileishmanial activity, with IC50 values between 2.11 and 3.25 µg.mL-1 against promastigote and amastigote forms, low toxicity and selectivity indexes ranging from 8.5 to 17.2. Conclusion: Our findings demonstrate that the fractions and cucurbitacin-type triterpenoids obtained from the aerial parts of M. charantia are promising natural leishmanicidal candidates.

9.
Mutat Res ; 757(1): 91-6, 2013 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-23892138

RESUMEN

The somatic mutation and recombination test (SMART) in wing cells of Drosophila melanogaster was used to test the mutagenic and recombinogenic activities of five aporphinoid alkaloids isolated from Ocotea acutifolia: thalicminine (1), (+)-dicentrine (2), (+)-ocoteine (3), (+)-6S-ocoteine N-oxide (4), and (+)-leucoxine (5). Third-stage larvae derived from the standard cross with wing cell markers mwh and/or flr(3) were treated chronically. The frequencies of mutant spots observed in marked heterozygous descendants revealed significant dose-dependent genotoxicity for alkaloids 1-4; compounds 1 and 2 were the most active. Alkaloids 1-4 also induced mitotic recombination. The presence of a methoxyl group at C-3 (as in compound 3) lowers its genotoxic effect relative to that of unsubstituted analogue 2, and the introduction of an N-oxide functionality (3 vs. 4) further reduces genotoxicity. The very planar conformation of oxo-aporphine alkaloid 1 may account for its higher genotoxicity vs. its less-planar analogues 3 and 4. As previously reported for (+)-dicentrine (2), alkaloids 1, 3, and 4 may also be DNA intercalating agents, interfering with the catalytic activity of topoisomerases.


Asunto(s)
Alcaloides , Sustancias Intercalantes , Ocotea/química , Alcaloides/química , Alcaloides/farmacología , Animales , ADN-Topoisomerasas/metabolismo , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/genética , Sustancias Intercalantes/química , Sustancias Intercalantes/farmacología , Larva/efectos de los fármacos , Larva/genética , Mutagénesis , Mutación/genética , Ocotea/genética , Recombinación Genética/efectos de los fármacos
11.
Exp Appl Acarol ; 60(3): 421-30, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23344640

RESUMEN

A total of 73 ethanol extracts from different anatomical parts of 44 plant species belonging to 24 families, native to the Mid-Western region of Brazil, were assessed in vitro for their effect on the reproductive cycle of engorged females of the cattle tick Rhipicephalus (Boophilus) microplus, using the adult immersion test. All extracts were evaluated at the concentration of 0.2 % and, among the extracts tested, the one obtained from the fruits of Guarea kunthiana (Meliaceae) proved to be highly efficacious, showing 99.1 % of product effectiveness. Extracts from other three species were shown to be moderately active, namely Nymphaea amazonum trunk (Nymphaeaceae) [51.7 %], Strychnos pseudoquina trunk (Loganiaceae) [48 %] [corrected] and Ocotea lancifolia leaves (Lauraceae) [34.5 %], while the remaining extracts were shown to be weakly active or inactive. This is the first report on the bioactivity of these species on egg production by engorged females of R. microplus.


Asunto(s)
Acaricidas/toxicidad , Extractos Vegetales/toxicidad , Rhipicephalus/efectos de los fármacos , Control de Ácaros y Garrapatas , Animales , Brasil , Bovinos , Femenino , Magnoliopsida/química , Extractos Vegetales/aislamiento & purificación , Reproducción/efectos de los fármacos
12.
BMC Complement Med Ther ; 23(1): 374, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37872494

RESUMEN

BACKGROUND: Given the rising occurrence of antibiotic resistance due to the existence and ongoing development of resistant bacteria and phenotypes, the identification of new treatments and sources of antimicrobial agents is of utmost urgency. An important strategy for tackling bacterial resistance involves the utilization of drug combinations, and natural products derived from plants hold significant potential as a rich source of bioactive compounds that can act as effective adjuvants. This study, therefore, aimed to assess the antibacterial potential and the chemical composition of Miconia albicans, a Brazilian medicinal plant used to treat various diseases. METHODS: Ethanolic extracts from leaves and stems of M. albicans were obtained and subsequently partitioned to give the corresponding hexane, chloroform, ethyl acetate, and hydromethanolic phases. All extracts and phases had their chemical constitution investigated by HPLC-DAD-MS/MS and GC-MS and were assessed for their antibiofilm and antimicrobial efficacy against Staphylococcus aureus. Furthermore, their individual effects and synergistic potential in combination with antibiotics were examined against clinical strains of both S. aureus and Acinetobacter baumannii. In addition, 10 isolated compounds were obtained from the leaves phases and used for confirmation of the chemical profiles and for antibacterial assays. RESULTS: Based on the chemical profile analysis, 32 compounds were successfully or tentatively identified, including gallic and ellagic acid derivatives, flavonol glycosides, triterpenes and pheophorbides. Extracts and phases obtained from the medicinal plant M. albicans demonstrated synergistic effects when combined with the commercial antibiotics ampicillin and ciprofloxacin, against multi-drug resistant bacteria S. aureus and A. baumannii, restoring their antibacterial efficacy. Extracts and phases also exhibited antibiofilm property against S. aureus. Three key compounds commonly found in the samples, namely gallic acid, quercitrin, and corosolic acid, did not exhibit significant antibacterial activity when assessed individually or in combination with antibiotics against clinical bacterial strains. CONCLUSIONS: Our findings reveal that M. albicans exhibits remarkable adjuvant potential for enhancing the effectiveness of antimicrobial drugs against resistant bacteria.


Asunto(s)
Acinetobacter baumannii , Antiinfecciosos , Melastomataceae , Plantas Medicinales , Staphylococcus aureus , Ciprofloxacina/farmacología , Plantas Medicinales/química , Espectrometría de Masas en Tándem , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Ampicilina/farmacología , Antiinfecciosos/farmacología , Bacterias
13.
Braz J Microbiol ; 43(4): 1302-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24031956

RESUMEN

Ethanol extracts from six selected species from the Cerrado of the Central-Western region of Brazil, which are used in traditional medicine for the treatment of infectious diseases and other medical conditions, namely Erythroxylum suberosum St. Hil. (Erythroxylaceae), Hyptis crenata Pohl. ex Benth. (Lamiaceae), Roupala brasiliensis Klotz. (Proteaceae), Simarouba versicolor St. Hil. (Simaroubaceae), Guazuma ulmifolia Lam. (Sterculiaceae) and Protium heptaphyllum (Aubl.) March. (Burseraceae), as well as fractions resulting from partition of these crude extracts, were screened in vitro for their antifungal and antibacterial properties. The antimicrobial activities were assessed by the broth microdilution assay against six control fungal strains, Candida albicans, C. glabrata, C. krusei, C. parapsilosis, C. tropicalis and Cryptococcus neoformans, and five control Gram-positive and negative bacterial strains, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus. Toxicity of the extracts and fractions against Artemia salina was also evaluated in this work. All plants investigated showed antimicrobial properties against at least one microorganism and two species were also significantly toxic to brine shrimp larvae. The results tend to support the traditional use of these plants for the treatment of respiratory and gastrointestinal disorders and/or skin diseases, opening the possibility of finding new antimicrobial agents from these natural sources. Among the species investigated, Hyptis crenata, Erythroxylum suberosum and Roupala brasiliensis were considered the most promising candidates for developing of future bioactivity-guided phytochemical investigations.

14.
Nat Prod Res ; 36(24): 6224-6231, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35007163

RESUMEN

Two new tetrahydrofuran lignans 1-2, along with 2,3-seco-lup-20(29)-en-2,3-dioic acid (3), (-)-larreatricin (4), and 15 additional compounds were isolated from Combretum mellifluum (Combretaceae). Their structures were determined by 1D- and 2D- NMR spectroscopic data and HRESIMS. Another 15 compounds were identified after HPLC-DAD-MS/MS analysis. Tested against HT-29 (colon) neoplastic cells, lignan 1 showed marked cytotoxicity (GI50 = 3.9 µM) and high selectivity (SI > 227), compared with non-neoplastic NIH/3T3 cells, while 2 proved less cytotoxic, despite exhibiting SI > 75. Seco-triterpene 3 was strongly cytotoxic to 786-0 (kidney) and HT-29 cells (GI50 = 0.5 and 2.9 µM, respectively), proving roughly 107 and 18 times more selective for these cell lines, respectively, than for NIH/3T3 cells. After 48 h of incubation, 1-3 exhibited potent cytostatic activity against HT-29 cells at all concentrations tested, while 3 had a cytocidal effect on 786-0 cells at 25 µg.mL-1.


Asunto(s)
Combretum , Lignanos , Neoplasias , Triterpenos , Ratones , Animales , Humanos , Combretum/química , Triterpenos/farmacología , Triterpenos/química , Lignanos/farmacología , Lignanos/química , Espectrometría de Masas en Tándem , Estructura Molecular , Línea Celular Tumoral
15.
J Med Food ; 24(3): 273-281, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32543997

RESUMEN

Flavonoids-compounds abundant in balanced daily diets-have been extensively investigated for biological activity. The pronounced antiproliferative effects of flavonoids have prompted studies to elucidate their mode of action against tumor cells. The anticancer properties of myricetin, a 3',4',5'-tri-hydroxylated flavonol, have been confirmed for a number of neoplasms, but myricitrin, its 3-O-rhamnoside derivative found in fruits and other parts of edible plants, has been scarcely investigated as a chemopreventive agent. This study evaluated the antiproliferative potential of myricitrin obtained from Combretum lanceolatum (Combretaceae) against MCF7 (breast), PC-3 (prostate), HT-29 (colon), 786-0 (kidney), and HL-60 (acute promyelocytic leukemia) cancer cell lines, using the sulforhodamine B and tetrazolium salt assays. Myricitrin proved most effective in inhibiting growth of HL-60 cells (GI50 = 53.4 µmol·L-1), yet showed weak antiproliferative activity against other cell lines. Possible cytotoxic mechanisms involving inhibition of topoisomerases I and IIα by myricitrin were also evaluated, revealing inhibitory activity only against topoisomerase IIα. The results suggested that topoisomerase IIα inhibition is the probable mechanism responsible for the antiproliferative activity of myricitrin. In vivo mutagenicity by myricitrin and its possible antimutagenic effect on doxorubicin-induced DNA damage were also investigated by performing the somatic mutation and recombination test (SMART) on Drosophila melanogaster. Myricitrin proved nonmutagenic to the offspring of standard (ST) and high-bioactivation (HB) crosses, while cotreatments with doxorubicin revealed the antimutagenic properties of myricitrin, even under conditions of high metabolic activation.


Asunto(s)
Combretum , Animales , Línea Celular Tumoral , Doxorrubicina , Drosophila melanogaster , Flavonoides/farmacología , Mutágenos/toxicidad
16.
PLoS One ; 16(1): e0245882, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33507972

RESUMEN

Butanolides have shown a variety of biological effects including anti-inflammatory, antibacterial, and antiprotozoal effects against certain strains of Trypanosoma cruzi. Considering the lack of an effective drug to treat T. cruzi infections and the prominent results obtained in literature with this class of lactones, we investigated the anti-T. cruzi activity of five butanolides isolated from two species of Lauraceae, Aiouea trinervis and Mezilaurus crassiramea. Initially, the activity of these compounds was evaluated on epimastigote forms of the parasite, after a treatment period of 4 h, followed by testing on amastigotes, trypomastigotes, and mammalian cells. Next, the synergistic effect of active butanolides against amastigotes was evaluated. Further, metacyclogenesis inhibition and infectivity assays were performed for the most active compound, followed by ultrastructural analysis of the treated amastigotes and trypomastigotes. Among the five butanolides studied, majoranolide and isoobtusilactone A were active against all forms of the parasite, with good selectivity indexes in Vero cells. Both butanolides were more active than the control drug against trypomastigote and epimastigote forms and also had a synergic effect on amastigotes. The most active compound, isoobtusilactone A, which showed activity against all tested strains inhibited metacyclogenesis and infection of new host cells. In addition, ultrastructural analysis revealed that this butanolide caused extensive damage to the mitochondria of both amastigotes and trypomastigotes, resulting in severe morphological changes in the infective forms of the parasite. Altogether, our results highlight the potential of butanolides against the etiologic agent of Chagas disease and the relevance of isoobtusilactone A as a strong anti-T. cruzi drug, affecting different events of the life cycle and all evolutionary forms of parasite after a short period of exposure.


Asunto(s)
Alcanos/farmacología , Lactonas/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Chlorocebus aethiops , Sinergismo Farmacológico , Estadios del Ciclo de Vida/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/ultraestructura , Células Vero
17.
EXCLI J ; 19: 323-333, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32327956

RESUMEN

In a search for new antitrypanosomal agents in the Brazilian flora, the ethanol extract of the xylopodium from Aiouea trinervis (Lauraceae) exhibited in vitro activity against the epimastigote forms of Trypanosoma cruzi, the etiological agent of Chagas disease. Bioassay-guided chromatographic fractionation of the ethanol extract afforded three butanolides, isoobtusilactone A (1), epilitsenolide C2 (2), and epilitsenolide C1 (3). Butanolides 1 and 3 were more active against T. cruzi epimastigotes than the reference drug benznidazole (by 8.9-fold and 3.2-fold, respectively), while 2 proved inactive. Compounds 1 and 3 showed low cytotoxicity in mammalian Vero cells (CC50> 156 µmol L-1) and high selectivity index (SI) values for epimastigotes (SI = 56.8 and 28.6, respectively), and 1 was more selective than benznidazole (SI = 46.5). Butanolide 1 at 24 µmol L-1 also led to cell cycle alterations in epimastigote forms, and inhibited the growth of amastigote cells in more than 70 %. In silico ADMET properties of 1 were also analyzed and predicted favorable drug-like characteristics. This butanolide also complied with Lipinski's rule of five and was not predicted as interference compound (PAINS). This is the first report on the isolation of these bioactive butanolides under the guidance of in vitro trypanocidal activity against T. cruzi.

18.
Fitoterapia ; 146: 104707, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32827695

RESUMEN

Jatropha elliptica (Pohl) Oken (Euphorbiaceae) roots are used in folk medicine to treat gastric ulcers. The purpose of this work was to evaluate the gastroprotective activity of ethanol extract (JER) and hexane fraction (ERH) of J. elliptica roots in mice, as well as to analyze the acute toxicity of the extract and identify the potential active compounds. No signs of toxicity were observed in JER. In both acidified ethanol and indometacin-induced gastric ulcer models, all doses tested of JER and ERH significantly reduced gastric lesions. Dereplication of JER was performed by HPLC-DAD-ESI-MS/MS and resulted in the annotation of compounds fraxetin, propacin, jatrophone and jatropholones A and B. GC-MS analysis of ERH revealed the diterpenes jatrophone, jatropholone A and jatropholone B as the major components. The chemical study of this fraction has led to the isolation of these compounds, in addition to the sequiterpene cyperenoic acid and the diterpene 2ß-hydroxyjatrophone, both reported for the first time in J. elliptica. The isolated compounds were tested against L929 cells and only cyperenoic acid and the mixture of jatropholones A and B did not show toxicity, being then selected as good candidates for bioassays using acidified ethanol-induced gastric ulcer model. Cyperenoic acid significantly decreased gastric lesions and preserved gastric mucus layer. The mixture of jatropholones A and B caused a smaller reduction of gastric lesions, without preservation of the gastric mucus layer. The study showed that J. elliptica roots present gastroprotective activity in mice, without causing acute toxic effects. The activity is related, at least in part, to the occurrence of terpenes, mainly the sesquiterpene cyperenoic acid.


Asunto(s)
Antiulcerosos/farmacología , Jatropha/química , Extractos Vegetales/farmacología , Úlcera Gástrica/tratamiento farmacológico , Animales , Antiulcerosos/aislamiento & purificación , Brasil , Línea Celular Tumoral , Diterpenos , Femenino , Masculino , Medicina Tradicional , Ratones , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Raíces de Plantas/química , Sesquiterpenos , Úlcera Gástrica/inducido químicamente , Pruebas de Toxicidad Aguda
19.
Nutrients ; 12(11)2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33182564

RESUMEN

The aim of this study was to evaluate the therapeutic effects of two different doses (250 and 500 mg/kg) of Morinda citrifolia fruit aqueous extract (AE) in high-fat/high-fructose-fed Swiss mice. The food intake, body weight, serum biochemical, oral glucose tolerance test (OGTT), and enzyme-linked immunosorbent assay (ELISA), as well as histological analyses of the liver, pancreatic, and epididymal adipose tissue, were used to determine the biochemical and histological parameters. The chemical profile of the extract was determined by ultra-fast liquid chromatography-diode array detector-tandem mass spectrometry (UFLC-DAD-MS), and quantitative real-time PCR (qRT-PCR) was used to evaluate the gene expressions involved in the lipid and glucose metabolism, such as peroxisome proliferative-activated receptors-γ (PPAR-γ), -α (PPAR-α), fatty acid synthase (FAS), glucose-6-phosphatase (G6P), sterol regulatory binding protein-1c (SREBP-1c), carbohydrate-responsive element-binding protein (ChREBP), and fetuin-A. Seventeen compounds were tentatively identified, including iridoids, noniosides, and the flavonoid rutin. The higher dose of AE (AE 500 mg/kg) was demonstrated to improve the glucose tolerance; however, both doses did not have effects on the other metabolic and histological parameters. AE at 500 mg/kg downregulated the PPAR-γ, SREBP-1c, and fetuin-A mRNA in the liver and upregulated the PPAR-α mRNA in white adipose tissue, suggesting that the hypoglycemic effects could be associated with the expression of genes involved in de novo lipogenesis.


Asunto(s)
Glucosa/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Síndrome Metabólico/metabolismo , Morinda/química , Extractos Vegetales/farmacología , Tejido Adiposo , Animales , Dieta Alta en Grasa , Femenino , Fructosa , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa-6-Fosfatasa/metabolismo , Lipogénesis/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Síndrome Metabólico/inducido químicamente , Síndrome Metabólico/tratamiento farmacológico , Ratones , PPAR alfa/metabolismo , PPAR gamma/metabolismo , Fitoterapia , Extractos Vegetales/uso terapéutico , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo
20.
Molecules ; 13(11): 2717-28, 2008 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18978701

RESUMEN

Two new triterpene glucosides, beta-D-glucopyranosyl 2alpha,3beta,24-trihydroxyolean- 12-en-28-oate and beta-D-glucopyranosyl 2alpha,3beta,23,24-tetrahydroxyurs-12-en-28-oate, in addition to nine known compounds belonging to three different triterpene classes (oleanane-, ursane- and lupane-type) have been isolated from the stems of a specimen of Combretum laxum growing in the "Pantanal" of the central-western region of Brazil. Among the known triterpenes, beta-D-glucopyranosyl 2alpha,3beta,6beta-trihydroxyolean-12-en-28-oate is reported for the first time in the Combretaceae, while bellericoside and asiatic acid are described for the first time in the genus Combretum. The structures of the isolated compounds have been established on the basis of spectral techniques (1D-, 2D-NMR and MS). Their in vitro antifungal activities against standard strains of Candida albicans, C. krusei and Cryptococcus neoformans were also evaluated in this work.


Asunto(s)
Combretum/química , Triterpenos Pentacíclicos/química , Tallos de la Planta/química , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Candida/efectos de los fármacos , Candida albicans/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Triterpenos Pentacíclicos/aislamiento & purificación , Triterpenos Pentacíclicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología
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