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1.
Molecules ; 27(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897874

RESUMO

This work evaluated the metabolic profiling of Inga species with antitumor potential. In addition, we described the antigenotoxicity of polyphenols isolated from I. laurina and a proteomic approach using HepG2 cells after treatment with these metabolites. The in vitro cytotoxic activity against HepG2, HT-29 and T98G cancer cell lines was investigated. The assessment of genotoxic damage was carried out through the comet assay. The ethanolic extract from I. laurina seeds was subjected to bioassay-guided fractionation and the most active fractions were characterized. One bioactive fraction with high cytotoxicity against HT-29 human colon cancer cells (IC50 = 4.0 µg mL-1) was found, and it was characterized as a mixture of p-hydroxybenzoic acid and 4-vinyl-phenol. The I. edulis fruit peel (IC50 = 18.6 µg mL-1) and I. laurina seed (IC50 = 15.2 µg mL-1) extracts had cytotoxic activity against the cell line T98G, and its chemical composition showed a variety of phenolic acids. The chemical composition of this species indicated a wide variety of aromatic acids, flavonoids, tannins, and carotenoids. The high concentration (ranging from 5% to 30%) of these polyphenols in the bioactive extract may be responsible for the antitumor potential. Regarding the proteomic approach, we detected proteins directly related to the elimination of ROS, DNA repair, expression of tumor proteins, and apoptosis.


Assuntos
Fabaceae , Polifenóis , Flavonoides/química , Flavonoides/farmacologia , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Proteômica
2.
J Nat Prod ; 77(3): 668-72, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24588269

RESUMO

Two new eremophilane-type sesquiterpenes, xylarenones F (3) and G (4), have been isolated from solid substrate cultures of a Camarops sp. endophytic fungus isolated from Alibertia macrophylla, together with the known compounds xylarenones C (1) and D (2). The structures and relative configurations of 1-4 were elucidated by extensive NMR and HRESIMS spectroscopic analysis. Due to their effects on the respiratory burst of neutrophils, which included inhibition of the reactive oxygen species production, these sesquiterpenes exhibited potential anti-inflammatory and antioxidant properties.


Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Ascomicetos/química , Rubiaceae/microbiologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Anti-Inflamatórios não Esteroides/química , Antioxidantes/química , Brasil , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Espécies Reativas de Oxigênio/antagonistas & inibidores , Sesquiterpenos/química , Azul Tripano
3.
Molecules ; 19(6): 8124-39, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24941338

RESUMO

Ethyl ferulate (FAEE) has been widely studied due to its beneficial heath properties and, when incorporated in creams, shows a high sun protection capacity. Here we aimed to compare FAEE and its precursor, ferulic acid (FA), as free radical scavengers, inhibitors of oxidants produced by leukocytes and the alterations in rheological properties when incorporated in emulsion based creams. The cell-free antiradical capacity of FAEE was decreased compared to FA. However, FAEE was more effective regarding the scavenging of reactive oxygen species produced by activated leukocytes. Stress and frequency sweep tests showed that the formulations are more elastic than viscous. The viscoelastic features of the formulations were confirmed in the creep and recovery assay and showed that the FAEE formulation was less susceptive to deformation. Liberation experiments showed that the rate of FAEE release from the emulsion was slower compared to FA. In conclusion, FAEE is more effective than FA as a potential inhibitor of oxidative damage produced by oxidants generated by leukocytes. The rheological alterations caused by the addition of FAEE are indicative of lower spreadability, which could be useful for formulations used in restricted areas of the skin.


Assuntos
Anti-Inflamatórios/química , Ácidos Cafeicos/química , Cosméticos/química , Emulsões/química , NADPH Oxidases
4.
Artigo em Inglês | MEDLINE | ID: mdl-22675379

RESUMO

Fungal infections in humans have increased alarmingly in recent years, particularly in immunocompromised individuals. Among the infections systemic candidiasis, aspergillosis, cryptococcosis, paracoccidioidomycosis, and histoplasmosis mortality are more prevalent and more severe in humans. The current high incidence of dermatophytosis is in humans, especially as the main etiologic agents Trichophyton rubrum and Trichophyton mentagrophytes. Molecules pristimerin and maytenin obtained from the plant Maytenus ilicifolia (Celastraceae) are known to show various pharmacological activities. This study aimed to evaluate the spectrum of antifungal activity of maytenin and pristimerin and their cytotoxicity in human keratinocytes (NOK cells of the oral mucosa). It was concluded that the best spectrum of antifungal activity has been shown to maytenin with MIC varying from 0.12 to 125 mg/L, although it is also active with pristimerin MIC ranging between 0.12 and 250 mg/L. Regarding the toxicity, both showed to have high IC(50). The SI showed high pristimerin against some species of fungi, but SI maytenin was above 1.0 for all fungi tested, showing a selective action of fungi. However, when comparing the two substances, maytenin also showed better results. The two molecules can be a possible prototype with a broad spectrum of action for the development of new antifungal agents.

5.
Nat Prod Res ; 36(7): 1898-1903, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32901524

RESUMO

Natural Products phytochemical provide a rich source for therapeutic discovery and has led to the development of many drugs. Thus, the aim of this study was to obtaining a metabolic profiling from ethanol extract of Inga semialata leaves (EEIS) selected by bioassay antimalarial and nematostatic and identify metabolites in mixture by co-injection experiments and NMR spectroscopy. The chemical composition of this species indicated a wide variety of aromatic acids (vanillic acid, 3,4,5-trimethoxy benzoic acid, gallic acid, methyl gallate, p-coumaric acid and ferulic acid), flavonoids (quercetin, myricetin-3-O-rhamnoside and myricetin-3-O-(2"-O-galloyl)-α-rhamnopyranoside), triterpenes (lupeol, α-amyrin, friedelin and oleanolic acid) and the 2-hydroxyethyl-dodecanoate. The antimalarial assay showed that the I. semialata n-hexane fraction presented higher inhibition percentage than the Chloroquine standard and may be considered a potential source of compounds with antimalarial activity while the EEIS and its fractions showed nematostatic potential below 17% in the assay of nematostatic evaluation against the parasite Meloidogyne incognita.


Assuntos
Fabaceae , Antiparasitários/farmacologia , Fabaceae/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Folhas de Planta/química
6.
J Nat Prod ; 74(3): 487-91, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21341711

RESUMO

A lignan with a new skeleton named chimarrhinin (1) was isolated from an extract of the leaves of Chimarrhis turbinata, a Rubiaceae plant species. (13)C NMR spectrometric techniques including 1D and 2D experiments and HRESIMS provided unequivocal structural confirmation of this new C(6).C(3) skeleton type. The relative configuration of 1 was established by 2D (1)H-H analysis and J couplings, while its conformation was evaluated through molecular modeling using the RM1 semiempirical method, with the aid of coupling constants obtained by NMR analysis. The antioxidant activity of the new derivative 1 and two known and previously isolated phenolic derivatives (2 and 3) was investigated. An IC(50) value of 7.50 ± 0.5 µmol L(-1) was obtained for the new derivative 1, while 2 and 3 showed IC(50) values of 18.60 ± 0.4 and 18.50 ± 0.6 µmol, respectively.


Assuntos
Antioxidantes/isolamento & purificação , Lignanas/isolamento & purificação , Rubiaceae/química , Antioxidantes/química , Antioxidantes/farmacologia , Brasil , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química
7.
Mutagenesis ; 24(6): 501-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19736218

RESUMO

Casearia sylvestris is used in Brazil as a popular medicine to treat ulcer, inflammation and tumour. Caseargrewiin F is a clerodane diterpene isolated from the ethanolic leaf extract of C.sylvestris. The aim of the study was to assess the capacity of the ethanolic extract of C.sylvestris leaves and caseargrewiin F to protect DNA and verify if both the compounds cause some DNA damage, using the micronucleus (MN) test and comet assay in mice. Balb-C mice were treated with the extract [3.13, 6.25, 12.5, 25, 50 and 75 mg/kg body weight (b.w.)] and caseargrewiin F (0.16, 0.32, 0.63, 1.3, 2.5 and 3.8 mg/kg b.w.) for 14 days. On day 15, DNA damage was induced by intra-peritoneal (i.p.) injection of cyclophosphamide (CP) (i.p.) at 50 mg/kg b.w. after the MN test and comet assay were performed. A protective effect of ethanolic extract was observed in MN test (6.25 and 12.5 mg/kg b.w.) and the comet assay (3.13 and 6.25, 12.5 and 25 mg/kg b.w.). Caseargrewiin F showed protective effect at 0.63, 1.3 and 2.5 mg/kg b.w. only in comet assay. We also tested the ability of compounds of C.sylvestris to induce MN and to increase the comet assay tail moment. The experimental design was similar to the DNA protection assay except that in test groups we omitted the CP challenge. We observed increased damage at 50 and 75 mg/kg b.w. of ethanolic extract of C.sylvestris and caseargrewiin F at 3.18 mg/kg b.w. in both the MN test and comet assay. We conclude that ethanolic extract of C. sylvestris and caseargrewiin F can protect cells against DNA damage induced by CP at low concentrations, but at high concentrations these compounds also induce DNA damage.


Assuntos
Casearia/metabolismo , Dano ao DNA , Diterpenos/farmacologia , Etanol/química , Extratos Vegetais/farmacologia , Animais , Peso Corporal , Cromatografia Líquida de Alta Pressão , Ensaio Cometa , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes para Micronúcleos , Modelos Químicos , Folhas de Planta/metabolismo
8.
BMC Complement Altern Med ; 9: 15, 2009 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-19463163

RESUMO

BACKGROUND: Angiogenesis, a complex multistep process that comprehends proliferation, migration and anastomosis of endothelial cells (EC), has a major role in the development of pathologic conditions such as inflammatory diseases, tumor growth and metastasis. Brazilian flora, the most diverse in the world, is an interesting spot to prospect for new chemical leads, being an important source of new anticancer drugs. Plant-derived alkaloids have traditionally been of interest due to their pronounced physiological activities. We investigated the anti-angiogenic potential of the naturally occurring guanidine alkaloid pterogynidine (Pt) isolated from the Brazilian plant Alchornea glandulosa. The purpose of this study was to examine which features of the angiogenic process could be disturbed by Pt. METHODS: Human umbilical vein endothelial cells (HUVEC) were incubated with 8 muM Pt and cell viability, proliferation, apoptosis, invasion and capillary-like structures formation were addressed. Nuclear factor kappaB (NFkappaB), a transcription factor implicated in these processes, was also evaluated in HUVEC incubated with Pt. Quantifications were expressed as mean +/- SD of five independent experiments and one-way analysis of variance (ANOVA) followed by the Dunnet test was used. RESULTS: A significant decrease in proliferation and invasion capacity and an effective increase in apoptosis as assessed by bromodeoxyuridine (BrdU), double-chamber and terminal transferase dUTP nick end labeling (TUNEL) assay, respectively, have been found. Pt also led to a drastic reduction in the number of capillary-like structures formation when HUVEC were cultured on growth factor reduced-Matrigel (GFR-Matrigel) coated plates. In addition, incubation of HUVEC with Pt resulted in reduced NFkappaB activity. CONCLUSION: These findings emphasize the potential use of Pt against pathological situations where angiogenesis is stimulated as tumor development.


Assuntos
Alcaloides/farmacologia , Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Euphorbiaceae/química , Guanidinas/farmacologia , Extratos Vegetais/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Análise de Variância , Inibidores da Angiogênese/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular , Guanidinas/química , Guanidinas/isolamento & purificação , Humanos , Marcação In Situ das Extremidades Cortadas , NF-kappa B/antagonistas & inibidores , Invasividade Neoplásica , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Plantas Medicinais/química , Veias Umbilicais
9.
Nat Prod Res ; 33(3): 443-446, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29577744

RESUMO

Endophytic fungi were isolated from red alga Asparagopsis taxiformis - Falkenbergia stage, collected from the Brazilian coast, and were identified as Annulohypoxylon stygium (AT-03) and A. yungensis (AT-06) based on their macro/micromorphological and molecular features. Bioassay-guided fractionation of the EtOAc extract from laboratory cultures of both strains yielded known compounds pyrogallol from A. stygium, (3 R)-scytalone and (3 R,4 R)-4-hydroxy-scytalone from A. yungensis. Pyrogallol was active against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli strains. An inactive fraction from A. stygium afforded two additional compounds, (3 R,4 R)-3,4,5-trihydroxy-1-tetralone and tyrosol. Optically active compounds had their stereochemistry determined by circular dichroism (CD) spectroscopy.


Assuntos
Endófitos/química , Fungos/química , Hidrocarbonetos Aromáticos/isolamento & purificação , Pirogalol/farmacologia , Rodófitas/microbiologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Brasil , Escherichia coli/efeitos dos fármacos , Hidrocarbonetos Aromáticos/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Naftóis/isolamento & purificação , Naftóis/farmacologia , Pirogalol/isolamento & purificação , Estereoisomerismo
10.
Sci Rep ; 9(1): 12318, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444403

RESUMO

A chemical study of the EtOAc extract of Nemania bipapillata (AT-05), an endophytic fungus isolated from the marine red alga Asparagopsis taxiformis - Falkenbergia stage, led to the isolation of five new botryane sesquiterpenes, including the diastereomeric pair (+)-(2R,4S,5R,8S)-(1) and (+)-(2R,4R,5R,8S)-4-deacetyl-5-hydroxy-botryenalol (2), (+)-(2R,4S,5R,8R)-4-deacetyl-botryenalol (3), one pair of diastereomeric botryane norsesquiterpenes bearing an unprecedented degraded carbon skeleton, (+)-(2R,4R,8R)-(4) and (+)-(2R,4S,8S)-(5), which were named nemenonediol A and nemenonediol B, respectively, in addition to the known 4ß-acetoxy-9ß,10ß,15α-trihydroxyprobotrydial (6). Their structures were elucidated using 1D and 2D NMR, HRESIMS and comparison with literature data of similar known compounds. The absolute configurations of 2, 3 and 4 were deduced by comparison of experimental and calculated electronic circular dichroism (ECD) spectra, while those of 1 and 5 were assigned from vibrational circular dichroism (VCD) data. Compound 4 weakly inhibited acetylcholinesterase, whereas compound 1 inhibited both acetylcholinesterase and butyrylcholinesterase. Compounds 1, 3, 5 and 6 were tested against two carcinoma cell lines (MCF-7 and HCT-116), but showed no significant citotoxicity at tested concentrations (IC50 > 50 µM).


Assuntos
Endófitos/isolamento & purificação , Rodófitas/microbiologia , Terpenos/metabolismo , Xylariales/isolamento & purificação , Acetilcolinesterase/metabolismo , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Inibidores da Colinesterase/farmacologia , Células HCT116 , Humanos , Células MCF-7 , Espectroscopia de Prótons por Ressonância Magnética , Terpenos/química , Terpenos/isolamento & purificação
11.
J Agric Food Chem ; 55(7): 2569-74, 2007 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-17335225

RESUMO

Plants from Iryanthera genus have been traditionally used as food supplements by South American Indians. The MeOH extract of leaves of Iryanthera juruensis, one of the plants endemic to the Amazon region and consumed in Brazil, and the hexane extract from its seeds inhibited lipid peroxidation (LPO) and cyclooxygenase (COX-1 and -2)) enzymes in in vitro assays. Further analyses of these extracts yielded 5-deoxyflavones (1-5) from the leaf extract and sargachromenol (6), sargaquinoic acid (7), a novel juruenolic acid (8), omega-arylalkanoic acids (9a-c), and the lignan guaiacin (10) from the seed extract. Compounds 3-5 inhibited LPO by 86%, 77%, and 88% at 10 ppm, respectively, and compounds 6 and 9a-c showed inhibition at 76% and 78% at 100 ppm, respectively. However, compounds 7 and 8 were inactive and lignan 10 exhibited LPO inhibitory activity by 99% at 100 ppm compared to commercial antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and vitamin E. The flavones 1-5 also inhibited COX-1 and -2 enzymes by 50-65% at 100 ppm. Compound 6 showed high but nonselective inhibition of COX-1 and COX-2 enzymes, when compared to aspirin and Celebrex, a nonsteroidal anti-inflammatory drug (NSAID). Compounds 7 and 10 inhibited COX-1 by 60% and 65% and COX-2 by 37% and 18%, respectively, whereas compounds 8 and 9a-c showed little or no activity against these enzymes.


Assuntos
Inibidores de Ciclo-Oxigenase/isolamento & purificação , Peroxidação de Lipídeos/efeitos dos fármacos , Magnoliopsida/química , Extratos Vegetais/farmacologia , Brasil , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Folhas de Planta/química , Sementes/química
12.
Front Microbiol ; 8: 1048, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659880

RESUMO

Dodecyl protocatechuate (dodecyl) is a derivative of protocatechuic acid (3,4-dihydroxybenzoic acid) that possesses anti-oxidant and antifungal properties. Nanostructured lipid systems (NLS) can potentiate the action of many antifungal agents, reducing the required dose and side effects by improving their activity. This work aimed to evaluate dodecyl protocatechuate loaded into a NLS (NLS+dodecyl) as a strategy for the treatment of Paracoccidioides brasiliensis and P. lutzii in vitro. Antifungal activity against P. brasiliensis and P. lutzii was evaluated using the microdilution technique. NLS+dodecyl showed high antifungal activity with a minimum inhibitory concentration ranging from 0.06 to 0.03 µg/mL; 4- to 16-fold higher than that of free dodecyl. NLS+dodecyl was able to inhibit fungal adhesion of the extracellular artificial matrix proteins (laminin and fibronectin), resulting in 82.4 and 81% inhibition, respectively, an increase of 8-17% compared with free dodecyl. These findings corroborate previous results demonstrating 65 and 74% inhibition of fungal adhesion in pulmonary fibroblast cells by dodecyl and NLS+dodecyl, respectively, representing a 9% increase in inhibition for NLS+dodecyl. Subsequently, cytotoxicity was evaluated using the 0.4% sulforhodamine B assay. NLS+dodecyl did not exhibit cytotoxicity in MRC5 (human pneumocyte) and HepG2 (human hepatic carcinoma) cells, thus increasing the selectivity index for NLS+dodecyl. In addition, cytotoxicity was evaluated in vivo using the Caenorhabditis elegans model; neither dodecyl nor NLS+dodecyl exhibited any toxic effects. Taken together, these results suggest that NLS can be used as a strategy to improve the activity of dodecyl against P. brasiliensis and P. lutzii because it improves antifungal activity, increases the inhibition of fungal adhesion in lung cells and the extracellular matrix in vitro, and does not exhibit any toxicity both in vitro and in vivo.

13.
Chem Biodivers ; 2(3): 367-72, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17191985

RESUMO

A new quinonemethide triterpene named as salacin, has been isolated from the root bark of Salacia campestris in addition to the known pristimerin, maytenin, 20alpha-hydroxymaytenin, and netzahualcoyene. Salacin was identified on the basis of NMR-spectral and mass spectrometric analysis. The free-radical scavenging activities of the quinonemethide triterpenes salacin (1), pristimerin (2), maytenin (3), 20alpha-hydroxymaytenin (4), and netzahualcoyene (5) towards DPPH have been evaluated and showed absorbance variation (deltaA) of 19, 20, 39, 28, 55, and 10%, respectively, having rutin (74% at 50 microM) and BHT (7% at 50 microM) as standard compounds.


Assuntos
Antioxidantes/farmacologia , Salacia/química , Triterpenos/farmacologia , Antioxidantes/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Espectrofotometria Infravermelho , Triterpenos/isolamento & purificação
14.
Nat Prod Res ; 19(4): 319-23, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15938136

RESUMO

An ethanolic extract from the stems of Styrax camporum Pohl (Styracaceae), a plant traditionally used for gastrointestinal diseases, was fractionated and subjected to flash chromatography and afforded two benzofuran lignans, egonol and homoegonol, and one furofuran lignan, (+/-)syringaresinol, which were identified by spectral data interpretation. Their cytotoxic activities against Hep-2 (larynx epidermoid carcinoma), HeLa (human cervix carcinoma) and C6 (rat glioma) cell lines were evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay at several concentrations for 24h. Activities could be observed for egonol against C6 (IC50 = 3.2 microg/mL) and Hep-2 (IC50 = 3.6 microg/mL) cell lines, and for homoegonol against C6 (IC50 = 4.9 microg/mL) and HeLa (IC50 = 5.3 microg/mL) cells.


Assuntos
Anisóis/química , Anisóis/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Benzofuranos/química , Benzofuranos/farmacologia , Lignanas/química , Lignanas/farmacologia , Styrax/química , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular
15.
PLoS One ; 9(10): e110277, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25340774

RESUMO

Pro-oxidant effects of phenolic compounds are usually correlated to the one-electron redox potential of the phenoxyl radicals. Here we demonstrated that, besides their oxidizability, hydrophobicity can also be a decisive factor. We found that esterification of protocatechuic acid (P0) provoked a profound influence in its pro-oxidant capacity. The esters bearing alkyl chains containing two (P2), four (P4) and seven (P7) carbons, but not the acid precursor (P0), were able to exacerbate the oxidation of trolox, α-tocopherol and rifampicin. This effect was also dependent on the catechol moiety, since neither gallic acid nor butyl gallate showed any pro-oxidant effects. A comparison was also made with apocynin, which is well-characterized regarding its pro-oxidant properties. P7 was more efficient than apocynin regarding co-oxidation of trolox. However, P7 was not able to co-oxidize glutathione and NADH, which are targets of the apocynin radical. A correlation was found between pro-oxidant capacity and the stability of the radicals, as suggested by the intensity of the peak current in the differential pulse voltammetry experiments. In conclusion, taking into account that hydroquinone and related moieties are frequently found in biomolecules and quinone-based chemotherapeutics, our demonstration that esters of protocatechuic acid are specific and potent co-catalysts in their oxidations may be very relevant as a pathway to exacerbate redox cycling reactions, which are usually involved in their biological and pharmacological mechanisms of action.


Assuntos
Hidroxibenzoatos/farmacologia , Oxidantes/farmacologia , Acetofenonas/química , Acetofenonas/metabolismo , Antioxidantes/farmacologia , Cromanos , Técnicas Eletroquímicas , Esterificação , Glutationa/metabolismo , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Hidroxibenzoatos/química , Hidroxilação/efeitos dos fármacos , Cinética , Redes e Vias Metabólicas/efeitos dos fármacos , NAD/metabolismo , Oxirredução/efeitos dos fármacos , Rifampina/farmacologia , alfa-Tocoferol/farmacologia
16.
Food Chem Toxicol ; 53: 153-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23200890

RESUMO

Studies have shown that Casearia sylvestris compounds protect DNA from damage both in vitro and in vivo. Complementarily, the aim of the present study was to assess the chemopreventive effect of casearin B (CASB) against DNA damage using the Ames test, the comet assay and the DCFDA antioxidant assay. The genotoxicity was assessed by the comet assay in HepG2 cells. CASB was genotoxic at concentrations higher than 0.30 µM when incubated with the FPG (formamidopyrimidine-DNA glycosylase) enzyme. For the antigenotoxicity comet assay, CASB protected the DNA from damage caused by H(2)O(2) in the HepG2 cell line in concentrations above 0.04 µM with post-treatment, and above 0.08 µM with pre-treatment. CASB was not mutagenic (Ames test) in TA 98 and TA 102. In the antimutagenicity assays, the compound was a strong inhibitor against aflatoxin B1 (AFB) in TA 98 (>88.8%), whereas it was moderate (42.7-59.4%) inhibitor against mytomicin C (MMC) in TA 102. Additionally, in the antioxidant assay using DCFDA, CASB reduced reactive oxygen species (ROS) generated by H(2)O(2). In conclusion, CASB was genotoxic to HepG2 cells at high concentrations; was protective of DNA at low concentrations, as shown by the Ames test and comet assay; and was also antioxidant.


Assuntos
Antioxidantes/farmacologia , Casearia/química , Diterpenos Clerodânicos/farmacologia , Diterpenos/farmacologia , Extratos Vegetais/farmacologia , Aflatoxina B1/metabolismo , Aflatoxina B1/toxicidade , Antimutagênicos/farmacologia , Quimioprevenção , Ensaio Cometa/métodos , Dano ao DNA/efeitos dos fármacos , DNA-Formamidopirimidina Glicosilase/genética , DNA-Formamidopirimidina Glicosilase/metabolismo , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Peróxido de Hidrogênio/efeitos adversos , Mutagênicos/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo
17.
J Med Food ; 14(10): 1244-53, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21663472

RESUMO

Alchornea glandulosa has traditionally been used in Brazilian folk medicine for the treatment of immune-inflammatory diseases and as an antiulcer agent to heal gastric ulcer and gastritis. Angiogenesis is a complex multistep process that consists of proliferation, migration, and anastomosis of endothelial cells and has a major role in the development of pathologic conditions, such as inflammatory diseases. To investigate a possible link between the anti-inflammatory activities and antiangiogenic effects of A. glandulosa ethyl acetate fraction (AGF), this study examined which features of the angiogenic process could be disturbed by this fraction. The antiangiogenic activity of AGF was determined in vitro by using human umbilical vein endothelial cells (HUVEC), and cell viability, proliferation, apoptosis, invasion, and capillary-like structures formation were addressed. To elucidate the mechanism of action, nuclear factor κB (NFκB), a transcription factor implicated in these processes, was also evaluated in HUVEC incubated with AGF. A significant decrease in proliferation, a relevant increase in apoptosis, and a strong reduction in invasion capacity (as assessed by bromodeoxyuridine, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling, and double-chamber assays, respectively) were observed. AGF also led to a drastic reduction in the number of capillary-like structures formed when HUVEC were cultured on growth factor-reduced Matrigel-coated plates. In addition, incubation of HUVEC with AGF resulted in reduced NFκB activity. These findings emphasize the antiangiogenic potential of AGF and support its therapeutic use for disorders that involve excessive angiogenesis, such as chronic inflammation and tumor growth.


Assuntos
Inibidores da Angiogênese/farmacologia , Euphorbiaceae/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Extratos Vegetais/farmacologia , Acetatos , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Marcação In Situ das Extremidades Cortadas , NF-kappa B/genética , NF-kappa B/metabolismo , Invasividade Neoplásica , Neovascularização Patológica , Transdução de Sinais , Fatores de Transcrição , Veias Umbilicais
18.
Nat Prod Res ; 24(18): 1758-65, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20408045

RESUMO

Gallic acid (3,4,5-trihydroxybenzoic acid), found in many plants either in free-form or part of tannins, is known to possess anti-microbial, antioxidant and cytotoxic properties. NFκB regulates the expression of several genes involved in carcinogenesis. These include anti-apoptotic, cytokines and cell cycle-regulatory genes. It is well established that the transcriptional factor NFκB is deregulated in many forms of cancer. Thus, agents that can suppress NFκB activation have the potential of suppressing carcinogenesis. In the present investigation, gallic acid was isolated from Alchornea glandulosa (Euphorbiaceae) and eight esters were synthesised. These compounds were evaluated against TNF-α-induced NFκB activation with stably transfected 293/NFκB-Luc human embryonic kidney cells. Gallates with IC(50) values in a range of 10-56 µM mediated inhibitory activity higher than gallic acid (IC(50) 76.0 ± 4.9 µM). In addition to inhibiting NFκB activation, gallic acid mediated a modest cytotoxic effect, and some of the gallates affected cell viability at the tested concentrations. Based on these results, suppression of NFκB activation by gallate esters could play a chemopreventive role in carcinogenesis.


Assuntos
Euphorbiaceae/química , Ácido Gálico/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Neoplasias/prevenção & controle , Análise de Variância , Linhagem Celular , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Humanos , Concentração Inibidora 50 , Luciferases , Estrutura Molecular , Fator de Necrose Tumoral alfa/metabolismo
19.
Expert Opin Ther Pat ; 19(4): 461-73, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19441926

RESUMO

BACKGROUND: Plants synthesise a vast repertoire of chemicals with various biological activities. Brazilian enormous botanical diversity facilitates the development of novel ethical drugs for the treatment of diseases in humans. OBJECTIVE: To present therapeutic patent applications comprising Brazilian native plants published in the 2003-2008 period in light of legal aspects of patentability of biodiversity and public health concerns. METHODS: Therapeutic patent applications related to Brazilian medicinal plants available at both the European Patent Office and the Brazilian National Institute of Industrial Property databases were reviewed. RESULTS/CONCLUSION: Twenty-five patents are presented, most of which concern inflammatory, allergic, parasitic, infectious or digestive diseases, including extracts from Carapa guianensis, Copaifera genus, Cordia verbenacea, Erythrina mulungu, Physalis angulata and other pharmaceutical compositions with antileishmanial, antimalarial or trypanocidal activity. Brazilian research centres and universities are responsible for most of these inventions.


Assuntos
Fitoterapia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Biodiversidade , Brasil , Indústria Farmacêutica , Humanos , Medicina Tradicional , Patentes como Assunto/legislação & jurisprudência
20.
J Nat Prod ; 70(12): 2026-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18047293

RESUMO

Phytochemical work in the search for bioactive metabolites from the methanolic extract of Senna spectabilis green fruits led to the isolation of a new piperidine alkaloid, (+)-3- O-feruloylcassine ( 1), in addition to the known (-)-spectaline ( 2) and (-)-3- O-acetylspectaline ( 3). The isolates were submitted to in vitro evaluation of lipoperoxidation (LPO) and cyclooxygenase enzymes (COX-1 and -2) inhibitory properties and showed moderate antioxidant activities (40-70%) at 100 ppm when compared to commercial standards BHT and vitamin E and moderate inhibition of COX-1 (ca . 40%) and marginal inhibition of COX-2 enzymes (<10%) at 100 ppm when compared to nonsteroidal anti-inflammatory drugs (NSAIDs) aspirin, rofecoxib, and celecoxib, respectively.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Cassia/química , Inibidores de Ciclo-Oxigenase/isolamento & purificação , Inibidores de Ciclo-Oxigenase/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Piperidinas/isolamento & purificação , Piperidinas/farmacologia , Plantas Medicinais/química , Alcaloides/química , Inibidores de Ciclo-Oxigenase/química , Estrutura Molecular , Piperidinas/química
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