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1.
Phytochem Anal ; 32(6): 1011-1026, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33738879

RESUMO

INTRODUCTION: Given the diversity of secondary metabolites produced by species of the genus Erythroxylum, in addition to the many methods that have already been described in the literature, modern screening and identification methodologies, such as dereplication, represent an efficient and quick strategy compared to the classic techniques linked to natural product research. OBJECTIVE: The objective of the present study was to determine the phenolic profiles obtained from three species of Erythroxylum (Erythroxylum pauferrense Plowman, Erythroxylum pulchrum A.St.-Hil. and Erythroxylum simonis Plowman) by dereplication using liquid chromatography coupled with ESI-MSn and HRESIMS. MATERIAL AND METHODS: Ethyl acetate and n-butanolic fractions from crude ethanolic extract of Erythroxylum species were analyzed by HPLC-ESI-MSn and HPLC-HRESIMS, in order to identify its corresponding compounds. Experiments were performed in negative ionization mode, and the metabolites were provisionally identified based on deprotonated molecules, molecular formulas, fragmentation patterns and literature data. The corresponding isolated compounds were characterized by 1 H and 13 C NMR spectroscopy. RESULTS: According to the dereplication method, it was possible to establish and compare the phenolic profile of the corresponding species by the assignment of 55 compounds, most of which were first described in these species and among which some were also new to the Erytroxylum genus. Additionally, nine compounds were isolated, including biphenyl-3,3',4,4'-tetraol, where the mass spectral data were not sufficient for their identification, and reported for the first time in the Erythroxylaceae family. CONCLUSION: This research contributes to the phytochemical knowledge of the Erythroxylum genus and demonstrates the importance of the dereplication method regarding the investigation of natural products, enabling accurate identification of the metabolites while avoiding the efforts and material expenses involved in the isolation of known compounds.


Assuntos
Erythroxylaceae , Espectrometria de Massas por Ionização por Electrospray , Cromatografia Líquida de Alta Pressão , Fenóis , Compostos Fitoquímicos , Extratos Vegetais
2.
Planta Med ; 87(1-02): 177-186, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33176378

RESUMO

Tropane alkaloids are specialized plant metabolites mostly found in the Erythroxylaceae and Solanaceae families. Although tropane alkaloids have a high degree of structural similarity because of the tropane ring, their pharmacological actions are quite distinct. Brazil is one of the main hotspots of Erythroxylum spp. diversity with 123 species (almost 66% of the species catalogued in tropical America). Erythroxylum pungens occurs in the Caatinga, a promising biome that provides bioactive compounds, including tropane alkaloids. As part of our efforts to investigate this species, 15 alkaloids in specimens harvested under different environmental conditions are presented herein. The occurrence of 3-(2-methylbutyryloxy)tropan-6,7-diol in the stem bark of plants growing in their natural habitat, greenhouse controlled conditions, and after a period of water restriction, suggests that it is a potential chemical marker for the species. This alkaloid was evaluated for several parameters in zebrafish (Danio rerio) as a model organism. Regarding toxicity, teratogenic effects were observed at 19.5 µM and the lethal dose for embryos was 18.4 µM. No mortality was observed in adults, but a behavioral screen showed psychostimulatory action at 116.7 µM. Overall, the alkaloid was able to cause zebrafish behavioral changes, prompting further investigation of its potential as a new molecule in the treatment of depression-like symptoms. In silico, targets involved in antidepressant pathways were identified by docking.


Assuntos
Alcaloides , Erythroxylaceae , Alcaloides/farmacologia , Animais , Brasil , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Tropanos , Peixe-Zebra
3.
Phytochemistry ; 178: 112458, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32888670

RESUMO

Six previously undescribed tropane alkaloids, designated as erythrobezerrines A-F, were isolated from the EtOH extract from the stem bark of Erythroxylum bezerrae Plowman. Their structures were elucidated based on the interpretation of the NMR and MS data and in some instances, confirmed by X-ray diffraction analysis. The cytotoxicity of the isolated compounds was evaluated against the cancer cell lines L929, PC-3, HCT-116, SNB-19 and NCI-H460, but only erythrobezerrine C showed moderate activity with IC50 values of 3.38 and 5.43 µM for HCT-116 and NCI-H460, respectively.


Assuntos
Erythroxylaceae , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Casca de Planta , Tropanos
4.
Biosci. j. (Online) ; 35(6): 1923-1931, nov./dec. 2019. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1049169

RESUMO

Erythroxylum citrifolium is a neotropical plant species recorded in all regions of Brazil. Determining leaf area is of fundamental importance to studies related to plant propagation and growth. The objective was to obtain an equation to estimate the leaf area of E. citrifolium from linear dimensions of the leaf blade (length and width). A total of 200 leaf blades were collected in Parque Estadual Mata do Pau-Ferro in the municipality of Areia, state of Paraíba, Northeast Brazil. The models evaluated were: linear, linear without intercept, quadratic, cubic, power and exponential. The best model was determined by the criteria of: high coefficient of determination (R²), low root mean square error (RMSE), low Akaike information criterion (AIC), high Willmott concordance index (d) and a BIAS index close to zero. All of the models constructed satisfactorily estimated the leaf area of E. citrifolium, with coefficients of determination above 0.9050, but the power model using the product between length and width (L*W) y = 0.5966 * LW1.0181 was the best, with the highest values of R² and d, low values of RMSE and AIC, and a BIAS index closest to zero.


Erythroxylum citrifolium é uma espécie de planta neotropical com registros em todas as regiões do Brasil. A determinação da área foliar é de fundamental importância em estudos relacionados a propagação e crescimento vegetal. O objetivo foi obter uma equação que permita estimar a área foliar de E. citrifolium a partir de dimensões lineares do limbo foliar (comprimento e largura). Foram coletados 200 limbos foliares no Parque Estadual Mata do Pau-Ferro, Areia, Paraíba, Nordeste do Brasil. Os modelos empregados foram: linear, linear sem intercepto, quadrático, cúbico, potencial e exponencial. Os critérios utilizados para escolher o melhor modelo, teve como base o maior coeficiente de determinação (R²), menor raiz do quadrado médio do erro (RMSE), menor critério de informação de Akaike (AIC), maior índice de concordância de Willmott (d) e índice BIAS mais próximo de zero. Todos os modelos construídos podem estimar satisfatoriamente a área foliar de E. citrifolium, com coeficientes determinação acima de 0,9050, porém o modelo potencial utilizando o produto entre comprimento e largura (L*W) y = 0,5966 * LW1,0181 é o mais indicado, com os maiores valores de R² e d, menores valores de RMSE e AIC, e índice BIAS mais próximo de zero.


Assuntos
Biometria , Erythroxylaceae
5.
Zootaxa ; 4604(1): zootaxa.4604.1.5, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31717204

RESUMO

Vallissiana universitaria Pereira Arévalo, a new genus and species of leaf-miner moth (Gracillariidae: Gracillariinae) is described and illustrated with the aid of optical and scanning electron microscopy, including adults, larva, pupa and the mine. Its monophyletic status is confirmed within the subfamily based on a DNA barcode CoI tree. The immature stages are associated with Erythroxylum argentinum O. E. Schulz (Erythroxylaceae) and four larval instars are found, all forming a round blotch mine from the beginning of ontogeny. The first two instars are sap-feeders, using only the epidermal cells, whereas the last two are tissue-feeders, mining the parenchyma cells. Pupation occurs inside the leaf mine within a flimsy, silk-made cocoon. This is the third endemic genus of gracillariid moths described from the Atlantic Forest of Brazil and the first associated with Erythroxylum P. Browne. Characteristics found on the forewing and in the last abdominal segments of the adult were determinant for the proposition of the new genus. The CoI tree indicated that it is closely related to Aspilapteryx, while this genus was recovered as polyphyletic in the analyses. Morphological evidence supports this polyphyly. Consequently, Sabulopteryx Triberti, 1985, stat. nov. is considered a valid genus.


Assuntos
Erythroxylaceae , Lepidópteros , Mariposas , Animais , Brasil , Florestas , Larva
6.
Molecules ; 24(20)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640255

RESUMO

The genus Erythroxylum contains species used by indigenous people of South America long before the domestication of plants. Two species, E. coca and E. novogranatense, have been utilized for thousands of years specifically for their tropane alkaloid content. While abuse of the narcotic cocaine has impacted society on many levels, these species and their wild relatives contain untapped resources for the benefit of mankind in the form of foods, pharmaceuticals, phytotherapeutic products, and other high-value plant-derived metabolites. In this review, we describe the current state of knowledge of members within the genus and the recent advances in the realm of molecular biology and biochemistry.


Assuntos
Erythroxylaceae/química , Extratos Vegetais/química , Animais , Erythroxylaceae/classificação , Humanos , Filogenia , Extratos Vegetais/farmacologia , América do Sul
7.
Molecules ; 24(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813289

RESUMO

Tropane alkaloids (TA) are valuable secondary plant metabolites which are mostly found in high concentrations in the Solanaceae and Erythroxylaceae families. The TAs, which are characterized by their unique bicyclic tropane ring system, can be divided into three major groups: hyoscyamine and scopolamine, cocaine and calystegines. Although all TAs have the same basic structure, they differ immensely in their biological, chemical and pharmacological properties. Scopolamine, also known as hyoscine, has the largest legitimate market as a pharmacological agent due to its treatment of nausea, vomiting, motion sickness, as well as smooth muscle spasms while cocaine is the 2nd most frequently consumed illicit drug globally. This review provides a comprehensive overview of TAs, highlighting their structural diversity, use in pharmaceutical therapy from both historical and modern perspectives, natural biosynthesis in planta and emerging production possibilities using tissue culture and microbial biosynthesis of these compounds.


Assuntos
Alcaloides/biossíntese , Alcaloides/farmacologia , Erythroxylaceae/química , Solanaceae/química , Alcaloides/química , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Humanos , Estrutura Molecular , Extratos Vegetais/biossíntese , Extratos Vegetais/farmacologia , Metabolismo Secundário , Tropanos/síntese química , Tropanos/química , Tropanos/farmacologia
8.
Am J Bot ; 106(1): 154-165, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30629286

RESUMO

PREMISE OF THE STUDY: This investigation establishes the first DNA-sequence-based phylogenetic hypothesis of species relationships in the coca family (Erythroxylaceae) and presents its implications for the intrageneric taxonomy and neotropical biogeography of Erythroxylum. We also identify the closest wild relatives and evolutionary relationships of the cultivated coca taxa. METHODS: We focused our phylogenomic inference on the largest taxonomic section in the genus Erythroxylum (Archerythroxylum O.E.Schulz) using concatenation and gene tree reconciliation methods from hybridization-based target capture of 427 genes. KEY RESULTS: We show that neotropical Erythroxylum are monophyletic within the paleotropical lineages, yet Archerythroxylum and all of the other taxonomic sections from which we sampled multiple species lack monophyly. We mapped phytogeographic states onto the tree and found some concordance between these regions and clades. The wild species E. gracilipes and E. cataractarum are most closely related to the cultivated E. coca and E. novogranatense, but relationships within this "coca" clade remain equivocal. CONCLUSIONS: Our results point to the difficulty of morphology-based intrageneric classification in this clade and highlight the importance of integrative taxonomy in future systematic revisions. We can confidently identify E. gracilipes and E. cataractarum as the closest wild relatives of the coca taxa, but understanding the domestication history of this crop will require more thorough phylogeographic analysis.


Assuntos
Domesticação , Erythroxylaceae/genética , Filogenia , Filogeografia , América do Sul
9.
Phytochemistry ; 155: 12-18, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30056276

RESUMO

Stem bark, root bark, and leaf extracts of Erythroxylum pungens were subjected to phytochemical analysis. N,N-dimethyltryptamine (DMT) was isolated and characterized from E. pungens roots. This unprecedented result is remarkable since no indole alkaloid has been previously reported from Erythroxylaceae so far. Eleven known tropane alkaloids were identified by their mass spectra and 3-(2-methylbutyryloxy)tropan-6,7-diol as well as 3-(2-methylbutyryloxy)nortropan-6,7-diol were isolated and characterized based on mass spectrometry, 1H, 13C, COSY, and NOESY NMR analysis. The complete NMR data are reported for the first time. Inverse Structure-based and Ligand-Based virtual screening were carried out to identify possible targets for 3-(2-methylbutyryloxy)tropan-6,7-diol. The level of cytotoxicity of this tropane alkaloid aliphatic ester was discrete with potencies on the order of 0.3-1.0 mg/mL and better results against HeLa (50% cell viability reduction). Otherwise, atropine (0.3 mg/mL), a Solanaceae tropane alkaloid, and DMT (0.5 mg/mL) from E. pungens roots impaired at 50% the cell viability against HeLa, SiHa, PC3, and 786-0. This study stimulates scientific investigation of the impact of edaphoclimatic features in a semi-arid environment on tropane alkaloid biosynthesis.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Erythroxylaceae/química , Simulação de Acoplamento Molecular , Alcaloides/química , Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
10.
Chachapollas; s.n; 2017. 79 p. ilus, tab, graf.
Tese em Espanhol | LILACS, MOSAICO - Saúde integrativa | ID: biblio-948868

RESUMO

El objetivo del presente estudio fue "Determinar la asociación entre la masticación de la hoja de coca y la prevención de la caries dental en los Pobladores del Caserío de Buenos Aires, Jaén ­ 2017". Se realizó con el enfoque cuantitativo; de nivel relacional de asociación de riesgo con un diseño de Cohortes; fue de tipo: observacional; prospectivo; longitudinal y analítico. La muestra fue de 33 pobladores donde 16 fueron los casos y 17 los controles. La recolección de datos se realizó mediante la lista de cotejo y la ficha del odontograma. Para contrastar la hipótesis se utilizó Riesgo Relativo (RR). Los resultados evidencian: antes del inicio de la investigación del 100% el 12.1 % que si mastica la hoja de la coca presentó caries dental mientras que el 18.2% que no mastican la hoja de la coca si presentó caries dental así mismo el 36.4% que mastican la hoja de la coca no presentaron caries dental mientras que el 33.3% que no mastican la hoja de la coca no presentaron caries dental; el valor del RR = 0.71, lo cual significa que la masticación de la hoja de coca es un factor protector de la caries dental. Después del estudio el 3.03% que si mastica la hoja de la coca presentó caries dental mientras que el 12.1% que no mastican si presentó caries dental, así mismo el 45.5% que mastican la hoja de la coca no presentó caries dental mientras que el 39.4% que no masticaron la hoja de coca no presentaron caries dental, el valor del RR = 0.27 significa que la masticación de la hoja de coca es un factor protector de la caries dental. En conclusión, la masticación de la hoja de coca es considerada como una medida preventiva de la caries dental


Assuntos
Humanos , Erythroxylaceae , Cárie Dentária , Peru , População Rural , Medicina Tradicional
11.
Rev. neuropsiquiatr ; 79(3): 166-168, jul.-sept. 2016.
Artigo em Espanhol | LILACS, LIPECS | ID: biblio-982937

RESUMO

El número de turistas que viajan a zonas de gran altitud en países andinos se está  incrementando en los últimos años, con aumento concomitante del riesgo de desarrollar el mal agudo de montaña. En las zonas alto andinas el mate de hoja de coca es usado frecuentemente para la prevención de este problema, pero las evidencias no soportan esta medida; se estima que, por el contrario, podría incrementar los síntomas del cuadro clínico que se intenta controlar por lo que se sugiere la conveniencia de no incentivar su uso.


In recent years, an increasing number of tourists visiting high altitude zones and places in Andean countries are, in turn, making a concomitantgreater risk of developing acute mountain sickness. In the Andean region, coca tea is frequently used for the prevention of this condition. However, existing evidence does not seem to support such use and, on the contrary, it is estimated that it may increase the symptoms. The convenience of not to encourage the use of coca tea forthe prevention of acute mountain sickness, is suggested.


Assuntos
Humanos , Doença da Altitude , Erythroxylaceae , Prevenção Primária
12.
J Sep Sci ; 39(14): 2720-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27214755

RESUMO

The absolute configuration of the naturally occurring isomers of 6ß-benzoyloxy-3α-tropanol (1) has been established by the combined use of chiral high-performance liquid chromatography with electronic circular dichroism detection and optical rotation detection. For this purpose (±)-1, prepared in two steps from racemic 6-hydroxytropinone (4), was subjected to chiral high-performance liquid chromatography with electronic circular dichroism and optical rotation detection allowing the online measurement of both chiroptical properties for each enantiomer, which in turn were compared with the corresponding values obtained from density functional theory calculations. In an independent approach, preparative high-performance liquid chromatography separation using an automatic fraction collector, yielded an enantiopure sample of OR (+)-1 whose vibrational circular dichroism spectrum allowed its absolute configuration assignment when the bands in the 1100-950 cm(-1) region were compared with those of the enantiomers of esters derived from 3α,6ß-tropanediol. In addition, an enantiomerically enriched sample of 4, instead of OR (±)-4, was used for the same transformation sequence, whose high-performance liquid chromatography follow-up allowed their spectroscopic correlation. All evidences lead to the OR (+)-(1S,3R,5S,6R) and OR (-)-(1R,3S,5R,6S) absolute configurations, from where it follows that samples of 1 isolated from Knightia strobilina and Erythroxylum zambesiacum have the OR (+)-(1S,3R,5S,6R) absolute configuration, while the sample obtained from E. rotundifolium has the OR (-)-(1R,3S,5R,6S) absolute configuration.


Assuntos
Erythroxylaceae/química , Tropanos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Estrutura Molecular , Estereoisomerismo , Tropanos/química
13.
Braz Dent J ; 27(1): 108-12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27007356

RESUMO

The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as "cabelo-de-negro". The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas.


Assuntos
Antineoplásicos/uso terapêutico , Erythroxylaceae/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Extratos Vegetais/uso terapêutico , Linhagem Celular Tumoral , Terapia Combinada , Humanos
14.
Cell Cycle ; 15(7): 948-56, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26918580

RESUMO

Plant-derived molecules showing antineoplastic effects have recently gained increased attention as potential adjuvants to traditional therapies for various cancers. Cerrado biome in Brazil contains high floral biodiversity, but knowledge about the potential therapeutic effects of compounds derived from that flora is still limited. The present study investigated the antineoplastic activity of Erythroxylum daphnites Mart., a Brazilian native plant from Cerrado biome, in the SCC-9 oral squamous cell carcinoma cell line. Cells were treated with various concentrations of hexane extract of Erythroxylum daphnites leaves (EDH) and assessed for cytotoxicity, proliferation, and apoptosis. Thin layer chromatography was conducted to characterize the substances present in EDH. Our results showed that EDH exerted anti-proliferative effects in SCC-9 cells by stabilizing the cell cycle at G1 phase in association with reduced intracellular levels of cyclins D and E and increased level of p21. EDH also demonstrated pro-apoptotic properties, as shown by an increased expression of caspase-3. Triterpenes were the major constituents of EDH. Our findings demonstrated a cytotoxic effect of EDH against SCC-9 cells in vitro mediated by the restraint of cellular proliferation and induction of apoptosis. Taken together, these findings support EDH constituents as potential therapeutic adjuvants for oral cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose , Carcinoma de Células Escamosas/metabolismo , Erythroxylaceae/química , Pontos de Checagem da Fase G1 do Ciclo Celular , Neoplasias Bucais/metabolismo , Antineoplásicos Fitogênicos/química , Carcinoma de Células Escamosas/patologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citotoxinas/química , Citotoxinas/farmacologia , Humanos , Neoplasias Bucais/patologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Triterpenos/química
15.
J Sep Sci ; 39(7): 1273-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26888377

RESUMO

Tropane alkaloids are bioactive metabolites with great importance in the pharmaceutical industry and the most important class of natural products found in the Erythroxylum genus. However, these compounds are usually separated by traditional chromatographic techniques, in which the sample is progressively purified in multiple chromatographic steps, resulting in a time- and solvent-consuming procedure. In this work we present the isolation of a novel alkaloid, 6ß,7ß-dibenzoyloxytropan-3α-ol, together with the two known 3α-benzoyloxynortropan-6ß-ol and 3α,6ß-dibenzoyloxytropane alkaloids, directly from the crude alkaloid fraction from the leaves of Erythroxylum subsessile, by using a single run pH-zone-refining counter-current chromatography method. The ethyl acetate/water (1:1, v/v) biphasic solvent system with triethylamine and HCl as retention and eluter agents, respectively, was used to isolate tropane alkaloids for the first time. The structures of the isolated alkaloids were elucidated by spectroscopic methods.


Assuntos
Distribuição Contracorrente/métodos , Erythroxylaceae/química , Folhas de Planta/química , Tropanos/isolamento & purificação , Concentração de Íons de Hidrogênio , Estrutura Molecular , Tropanos/química
16.
Braz. dent. j ; 27(1): 108-112, Jan.-Feb. 2016. graf
Artigo em Inglês | LILACS | ID: lil-777136

RESUMO

Abstract The mouth and oropharynx cancer is the 6th most common type of cancer in the world. The treatment may involve surgery, chemotherapy and radiotherapy. More than 50% of drugs against cancer were isolated from natural sources, such as Catharanthus roseus and epipodophyllotoxin, isolated from Podophyllum. The biggest challenge is to maximize the control of the disease, while minimizing morbidity and toxicity to the surrounding normal tissues. The Erythroxylum suberosum is a common plant in the Brazilian Cerrado biome and is popularly known as "cabelo-de-negro". The objective of this study was to evaluate the cytotoxic activity of Erythroxylum suberosum plant extracts of the Brazilian Cerrado biome associated with radiotherapy in human cell lines of oral and hypopharynx carcinomas. Cells were treated with aqueous, ethanolic and hexanic extracts of Erythroxylum suberosum and irradiated at 4 Gy, 6 Gy and 8 Gy. Cytotoxicity was evaluated by MTT assay and the absorbance was measured at 570 nm in a Beckman Counter reader. Cisplatin, standard chemotherapy, was used as positive control. The use of Erythroxylum suberosum extracts showed a possible radiosensitizing effect in vitro for head and neck cancer. The cytotoxicity effect in the cell lines was not selective and it is very similar to the effect of standard chemotherapy. The aqueous extract of Erythroxylum suberosum, combined with radiotherapy was the most cytotoxic extract to oral and hypopharynx carcinomas.


Resumo O câncer de boca e de orofaringe emerge como o 6º tipo de câncer mais comum no mundo. O tratamento pode envolver cirurgia, quimioterapia e radioterapia. Mais de 50% das drogas com atividade de combate ao câncer foram isoladas de fontes naturais, tais como a Catharanthus roseus e a epipodofilotoxina, isolada de Podophyllum. O maior desafio é maximizar o controle da doença, enquanto minimiza a morbidade e toxicidade para os tecidos normais circundantes. O Erythroxylum suberosum é uma planta comum no bioma Cerrado brasileiro e é popularmente conhecida como "cabelo-de-negro". O objetivo deste estudo foi avaliar a citotoxicidade dos extratos da planta Erythroxylum suberosum do bioma Cerrado brasileiro, associados à radioterapia em linhagens celulares humanas de carcinomas de língua e de hipofaringe. As células foram tratadas com os extratos aquoso, etanólico e hexânico do Erythroxylum suberosum e irradiadas com 4 Gy, 6 Gy e 8 Gy. A citotoxidade foi avaliada pelo ensaio de MTT e a absorvância foi medida a 570 nm em uma leitora Beckman. A cisplatina, quimioterápico padrão, foi utilizada como controle positivo. O uso de extratos de Erythroxylum suberosum mostrou potencial efeito radiosensibilizante in vitro no câncer de cabeça e pescoço. O efeito da citotoxicidade nas linhagens foi de forma não seletiva e muito semelhante ao efeito da quimioterapia padrão. O extrato aquoso de Erythroxylum suberosum, combinado com radioterapia, foi o extrato mais citotóxico para os carcinomas de língua e hipofaringe, associados à radioterapia.


Assuntos
Humanos , Antineoplásicos/uso terapêutico , Erythroxylaceae/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Extratos Vegetais/uso terapêutico , Linhagem Celular Tumoral , Terapia Combinada
17.
Anim Reprod Sci ; 164: 23-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26619941

RESUMO

Erythroxylum caatingae Plowman has a myorelaxing effect on smooth muscle tissue. We investigated the effect of the crude ethanolic extract of E. caatingae Plowman (Ec-EtOH) on the contractility of the ovine cervix. In an isometric system, circular strips were subjected to 90mM potassium (K(+)) or 30µM carbamylcholine (CCh)-induced contraction. We then exposed the tissue to cumulative concentrations of Ec-EtOH (1-729 µg/ml). In other bath solutions, the tissues were exposed to l-NG-nitroarginine methyl ester (l-NAME; 100µM), l-NAME (100µM)+l-arginine (300µM), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, ODQ; 5µM), 4-aminopyridine (4-AP; 3mM), tetraethylammonium (TEA; 0.3mM), glybenclamide (1µM), atosiban (10µM) or verapamil (3µM), followed by the addition of Ec-EtOH (1-729 µg/ml). We also evaluated the effect of cervical Ec-EtOH infusion (2mg) on cervical contractility in vivo. Ec-EtOH decreased cervical contractility induced by K(+) or CCh, and 729 µg/ml Ec-EtOH decreased 85.4±5.1% the amplitude of basal contractility in vitro, with an EC50 of 17.9±3.7 µg/ml. This effect of Ec-EtOH was prevented by l-NAME or ODQ. l-arginine impaired the blunting effect of l-NAME on cervical relaxation caused by Ec-EtOH. However, the potassium channel blockers 4-AP, TEA, and glybenclamide did not modify this myorelaxation triggered by Ec-EtOH. Ec-EtOH also decreased acetylcholine-induced contractions in tissue preincubated with verapamil. In addition, Ec-EtOH decreased ovine cervical contractions in vivo. Thus, Ec-EtOH had a relaxant effect on ovine cervical contractions. This may involve the nitric oxide signal, mediated by cGMP cellular transduction, and be related to intracellular calcium sequestration.


Assuntos
Colo do Útero/efeitos dos fármacos , GMP Cíclico/metabolismo , Erythroxylaceae/química , Óxido Nítrico/metabolismo , Extratos Vegetais/farmacologia , Ovinos , Animais , Feminino , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química
18.
Clin Oral Investig ; 19(3): 637-46, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25096669

RESUMO

OBJECTIVES: Antineoplastic effects of molecules derived from plants have recently gained increasing attention as an additive to traditional therapies. The aim of this study was to evaluate the cytotoxic activity of plant extracts from the Brazilian Cerrado biome associated with radiotherapy in head and neck carcinoma cells (HNSCC). MATERIALS AND METHODS: Fifteen extracts derived from five Cerrado plants were tested in HNSCC cell lines (SCC-25, SCC-9, FaDu) and keratinocyte cells (HaCat). Cell cytotoxicity of extracts and association extract/radiation (2Gy/min) was assessed by MTT assay. Cisplatin (50 µg/mL) was used as a positive control. Extracts with the major cytotoxic activity were selected and their IC50 concentrations were defined. Apoptosis was assessed using flow cytometric analysis. RESULTS: Ten isolated extracts resulted in moderate cytotoxicity (>20 and ≤ 50 % of viable cells), while three extracts induced severe cytotoxic effects (≤ 20 % of viable cells). Plant extracts treatment improved radiotherapy cytotoxicity in all cell lines. Although plant extracts are not as potent as cisplatin plus radiation, in FaDu cells, seven extracts associated with irradiation showed cytotoxic activity similar or better than the association of cisplatin and radiation. Hexanic extract of Erythroxylum daphinites could induce apoptosis in oral cancer cells; however, necrosis was the prevalent kind of death in FaDu cells treated with hexanic extract of Erythroxylum suberosum. CONCLUSIONS: Pre-treatment of HNSCC cells with the extract derived from Cerrado plants followed by irradiation induced a supra-additive cytotoxic effect. CLINICAL RELEVANCE: This study highlights the potential biological relevance of the Cerrado biome when associated with traditional therapy for cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Brasil , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Erythroxylaceae , Citometria de Fluxo , Humanos , Queratinócitos/efeitos dos fármacos , Medicina Tradicional , Carcinoma de Células Escamosas de Cabeça e Pescoço
19.
Plant Physiol ; 167(1): 89-101, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25406120

RESUMO

The esterification of methylecgonine (2-carbomethoxy-3ß-tropine) with benzoic acid is the final step in the biosynthetic pathway leading to the production of cocaine in Erythoxylum coca. Here we report the identification of a member of the BAHD family of plant acyltransferases as cocaine synthase. The enzyme is capable of producing both cocaine and cinnamoylcocaine via the activated benzoyl- or cinnamoyl-Coenzyme A thioesters, respectively. Cocaine synthase activity is highest in young developing leaves, especially in the palisade parenchyma and spongy mesophyll. These data correlate well with the tissue distribution pattern of cocaine as visualized with antibodies. Matrix-assisted laser-desorption ionization mass spectral imaging revealed that cocaine and cinnamoylcocaine are differently distributed on the upper versus lower leaf surfaces. Our findings provide further evidence that tropane alkaloid biosynthesis in the Erythroxylaceae occurs in the above-ground portions of the plant in contrast with the Solanaceae, in which tropane alkaloid biosynthesis occurs in the roots.


Assuntos
Aciltransferases/metabolismo , Cocaína/biossíntese , Proteínas de Plantas/metabolismo , Catálise , Cocaína/análogos & derivados , Cocaína/análise , Erythroxylaceae/enzimologia , Erythroxylaceae/metabolismo , Células do Mesofilo/enzimologia , Células do Mesofilo/metabolismo , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Proteínas de Plantas/química
20.
Rev. bras. plantas med ; 17(4,supl.3): 1169-1176, 2015. tab, graf
Artigo em Português | LILACS | ID: lil-776616

RESUMO

RESUMO As plantas medicinais representam um dos principais recursos terapêuticos utilizado pelo homem para a cura e prevenção de doenças, no entanto, para que o tratamento seja seguro e eficaz é necessário conhecer seus componentes químicos. Dessa forma, o intuito deste trabalho foi determinar os parâmetros farmacognosticos para o estabelecimento do controle de qualidade da droga vegetal composta pelas folhas de Erythroxylum suberosum A. St.-Hil., pertencentes à família Erythroxylaceae ocorrente no Cerrado. Para tanto, foram coletadas folhas adultas nas proximidades da Universidade Federal de Goiás, Goiânia-GO. Foram determinados o teor de umidade por meio de balança com irradiação de raios infravermelho e o teor de cinzas totais. Na prospecção fitoquímica foram pesquisadas as classes de metabólitos secundários e realizou-se o doseamento de fenóis totais, flavonoides e taninos totais. Os resultados dos testes de pureza realizados, teor de umidade e teor de cinzas totais, estão de acordo com os limites estabelecidos pelas especificações farmacopeicas. As análises fitoquímicas evidenciaram a presença de flavonoides, taninos, cumarinas, saponinas e resinas. No doseamento de fenóis totais, taninos e flavonoides presentes nas folhas de E. suberosum A. St.-Hil. obteve-se respectivamente 17,97%, 6,31%, 3,87%. Estes resultados confirmam os dados da literatura quanto à presença destes compostos em Erythroxylaceae, pois de acordo com nas folhas de E. tortuosum obteve-se valores de 10%, 8,4% e 0,064% de Fenóis, Taninos e flavonoides, respectivamente e nas folhas de E. deciduum foram encontrados 12,04% de fenóis totais, 0,87% de taninos e 1,37% de flavonoides. Os resultados encontrados no presente trabalho também se tornam relevantes quando comparadas as quantidades desses metabólitos com espécies clássicas na biossíntese de compostos fenólicos como o teor de taninos de Stryphnodendron adstringens (Mart.) Coville e em Eugenia uniflora L. foi de 29,9% e 2,96%, respectivamente. Teores de flavonóides que variaram entre 0,65% a 0,79% na Calendula officinalis L. e Ginkgo bilobaL. 0,59%, 0,75% e 0,79%. Sendo assim, a quantidade considerável de compostos fenólicos obtida em E. suberosum A. St.-Hil. sugere que a espécie possua um importante potencial terapêutico e quem sabe potencial antioxidante, a ser explorado em estudos posteriores.


ABSTRACT Medicinal plants represent a major therapeutic resources used by man for the cure and prevention of diseases, however, that the treatment be safe and effective it is necessary to know their chemical components. Thus, the aim of this work was to determine the pharmacognostic parameters for the establishment of the plant drug quality control made by the leaves of Erythroxylum suberosum A. St.-Hil., belonging to the family Erythroxylaceae occurring in the Cerrado. To this end, adult leaves were collected near the Federal University of Goiás, Goiânia-GO. It was determined the moisture content through scale radiating infrared rays and the content of total ash. The phytochemical screening of secondary metabolites classes were surveyed and performed the determination of total phenols, flavonoids and total tannins. The results of the purity tests, moisture content and total ash content, are in accordance with the limits established by the pharmacopeic specifications. The phytochemical analysis revealed the presence of flavonoids, tannins, coumarins, saponins and resins. The determination of total phenols, tannins and flavonoids quantities present in the leaves of E. suberosum A. St.-Hil. were obtained respectively as 17.97%, 6.31%, 3.87%. These results confirm the literature data for the presence of these compounds in Erythroxylaceae, since according to the leaves of E. tortuosum yielded values of 10%, 8.4% and 0.064% of phenols, tannins and flavonoids, respectively. On the E. deciduum leaves were found 12.04% of total phenols, tannins 0.87% and 1.37% of flavonoids. The results of this work also become relevant when comparing the amounts of these metabolites with classic species in the biosynthesis of phenolic compounds such as tannins content in barbatimão and pitanga was 29.9% and 2.96%, respectively. Flavonoid contents ranging from 0.65% to 0.79% in calendula and ginkgo 0.59%, 0.75% and 0.79%. Thus, considerable amount of phenolic compounds obtained in E. suberosum. A. St. Hil. It suggests that the species has an important therapeutic potential and who knows antioxidant potential to be explored in further studies.


Assuntos
Erythroxylaceae/química , Parâmetros de Referência/classificação , Plantas Medicinais/classificação , Fenóis/farmacologia , Controle de Qualidade
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