RESUMO
OBJECTIVE: In order to improve the contribution of medicines from traditional pharmacopoeia to health care, African countries like Burkina Faso have adopted for several years, policies and regulations organizing their distribution. This study aims to analyze the situation of the wholesale and retail sale of herbal medicines imported by the official pharmaceutical facilities. METHOD: This is a retrospective study involving all 18 drug wholesalers and 115 pharmacies in the city of Ouagadougou (Burkina Faso). It consisted of a collection of sales data of herbal medicines from 2013 to 2016 and interviews of the pharmacists responsible for the facilities surveyed. RESULTS: All the pharmacies surveyed obtain their supplies from national wholesalers, but eleven of them do so directly from manufacturers or non-wholesalers. Only 40% (44/111) of herbal medicines distributed by wholesalers and pharmacies had valid marketing authorizations. Also, although the average growth rates of annual sales by wholesalers and private pharmacies, respectively 23.67% and 11.94%, are significant, the turnover generated from their sale remains low. CONCLUSION: Supporting local producers with appropriate funding and adequate promotion of herbal medicines is still needed to boost the share of the national herbal medicines market.
Assuntos
Indústria Farmacêutica/estatística & dados numéricos , Fitoterapia/estatística & dados numéricos , Preparações de Plantas/provisão & distribuição , Plantas Medicinais , Burkina Faso , Indústria Farmacêutica/tendências , Promoção da Saúde , Humanos , Medicinas Tradicionais Africanas , Farmacêuticos , Fitoterapia/tendências , Estudos RetrospectivosRESUMO
Many plants require animal pollinators for successful reproduction; these plants provide pollinator resources in pollen and nectar (rewards) and attract pollinators by specific cues (signals). In a seeming contradiction, some plants produce toxins such as alkaloids in their pollen and nectar, protecting their resources from ineffective pollinators. We investigated signals and rewards in the toxic, protandrous bee-pollinated plant Aconitum napellus, hypothesizing that male-phase flower reproductive success is pollinator-limited, which should favour higher levels of signals (odours) and rewards (nectar and pollen) compared with female-phase flowers. Furthermore, we expected insect visitors to forage only for nectar, due to the toxicity of pollen. We demonstrated that male-phase flowers emitted more volatile molecules and produced higher volumes of nectar than female-phase flowers. Alkaloids in pollen functioned as chemical defences, and were more diverse and more concentrated compared to the alkaloids in nectar. Visitors actively collected little pollen for larval food but consumed more of the less-toxic nectar. Toxic pollen remaining on the bee bodies promoted pollen transfer efficiency, facilitating pollination.
Assuntos
Aconitum/fisiologia , Flores/fisiologia , Fenômenos Fisiológicos Vegetais , Pólen , Polinização , Reprodução , Alcaloides , Animais , Evolução Biológica , Néctar de Plantas/química , Pólen/químicaRESUMO
Photosensitizers (PS) are ideally devoid of any activity in the absence of photoactivation, and rely on molecular oxygen for the formation of singlet oxygen ((1)O2) to produce cellular damage. Off-targets and tumor hypoxia therefore represent obstacles for the use of PS for cancer photodynamic therapy. Herein, we describe the characterization of OR141, a benzophenazine compound identified through a phenotypic screening for its capacity to be strictly activated by light and to kill a large variety of tumor cells under both normoxia and hypoxia. This new class of PS unraveled an unsuspected common mechanism of action for PS that involves the combined inhibition of the mammalian target of rapamycin (mTOR) signaling pathway and proteasomal deubiquitinases (DUBs) USP14 and UCH37. Oxidation of mTOR and other endoplasmic reticulum (ER)-associated proteins drives the early formation of high molecular weight (MW) complexes of multimeric proteins, the concomitant blockade of DUBs preventing their degradation and precipitating cell death. Furthermore, we validated the antitumor effects of OR141 in vivo and documented its highly selective accumulation in the ER, further increasing the ER stress resulting from (1)O2 generation upon light activation.
Assuntos
Enzimas Desubiquitinantes/antagonistas & inibidores , Retículo Endoplasmático/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Oxigênio/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Humanos , Camundongos , Neoplasias/metabolismo , Oxirredução , Complexo de Endopeptidases do Proteassoma/metabolismo , Serina-Treonina Quinases TOR/fisiologiaRESUMO
Mallotus and Phyllanthus genera, both containing several species commonly used as traditional medicines around the world, are the subjects of this discrimination and classification study. The objective of this study was to compare different discrimination and classification techniques to distinguish the two genera (Mallotus and Phyllanthus) on the one hand, and the six species (Mallotus apelta, Mallotus paniculatus, Phyllanthus emblica, Phyllanthus reticulatus, Phyllanthus urinaria L. and Phyllanthus amarus), on the other. Fingerprints of 36 samples from the 6 species were developed using reversed-phase high-performance liquid chromatography with ultraviolet detection (RP-HPLC-UV). After fingerprint data pretreatment, first an exploratory data analysis was performed using Principal Component Analysis (PCA), revealing two outlying samples, which were excluded from the calibration set used to develop the discrimination and classification models. Models were built by means of Linear Discriminant Analysis (LDA), Quadratic Discriminant Analysis (QDA), Classification and Regression Trees (CART) and Soft Independent Modeling of Class Analogy (SIMCA). Application of the models on the total data set (outliers included) confirmed a possible labeling issue for the outliers. LDA, QDA and CART, independently of the pretreatment, or SIMCA after "normalization and column centering (N_CC)" or after "Standard Normal Variate transformation and column centering (SNV_CC)" were found best to discriminate the two genera, while LDA after column centering (CC), N_CC or SNV_CC; QDA after SNV_CC; and SIMCA after N_CC or after SNV_CC best distinguished between the 6 species. As classification technique, SIMCA after N_CC or after SNV_CC results in the best overall sensitivity and specificity.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Mallotus (Planta)/química , Phyllanthus/química , Plantas Medicinais/química , Análise Discriminante , Mallotus (Planta)/classificação , Phyllanthus/classificação , Extratos Vegetais/química , Extratos Vegetais/classificação , Plantas Medicinais/classificação , Análise de RegressãoRESUMO
The purpose of the research was to develop and validate a rapid quantification method able to screen many samples of yam bean seeds to determine the content of two toxic polyphenols, namely pachyrrhizine and rotenone. The analytical procedure described is based on the use of an internal standard (dihydrorotenone) and is divided in three steps: microwave assisted extraction, purification by solid phase extraction and assay by ultra high performance liquid chromatography (UHPLC). Each step was included in the validation protocol and the accuracy profiles methodology was used to fully validate the method. The method was fully validated between 0.25 mg and 5 mg pachyrrhizin per gram of seeds and between 0.58 mg/g and 4 mg/g for rotenone. More than one hundred samples from different accessions, locations of growth and harvest dates were screened. Pachyrrhizine concentrations ranged from 3.29 mg/g to lower than 0.25 mg/g while rotenone concentrations ranged from 3.53 mg/g to lower than 0.58 mg/g. This screening along with principal component analysis (PCA) and discriminant analysis (DA) analyses allowed the selection of the more interesting genotypes in terms of low concentrations of these two toxic polyphenols.
Assuntos
Pachyrhizus/química , Polifenóis/análise , Rotenona/análise , Sementes/química , Cromatografia Líquida de Alta Pressão/métodos , Análise Discriminante , Genótipo , Limite de Detecção , Micro-Ondas , Pachyrhizus/genética , Análise de Componente Principal , Padrões de Referência , Rotenona/análogos & derivados , Sementes/genética , Extração em Fase Sólida , Fatores de TempoRESUMO
Keetia leucantha is a West African tree used in traditional medicine to treat several diseases among which parasitic infections. The dichloromethane extract of leaves was previously shown to possess growth-inhibitory activities on Plasmodium falciparum, Trypanosoma brucei brucei and Leishmania mexicana mexicana with low or no cytotoxicity (>100 µg/ml on human normal fibroblasts) (Bero et al. 2009, 2011). In continuation of our investigations on the antitrypanosomal compounds from this dichloromethane extract, we analyzed by GC-FID and GC-MS the essential oil of its leaves obtained by hydrodistillation and the major triterpenic acids in this extract by LC-MS. Twenty-seven compounds were identified in the oil whose percentages were calculated using the normalization method. The essential oil, seven of its constituents and the three triterpenic acids were evaluated for their antitrypanosomal activity on Trypanosoma brucei brucei bloodstream forms (Tbb BSF) and procyclic forms (Tbb PF) to identify an activity on the glycolytic process of trypanosomes. The oil showed an IC(50) of 20.9 µg/ml on Tbb BSF and no activity was observed on Tbb PF. The best antitrypanosomal activity was observed for ursolic acid with IC(50) of 2.5 and 6.5 µg/ml respectively on Tbb BSF and Tbb PF. The inhibitory activity on a glycolytic enzyme of T. brucei, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), was also evaluated for betulinic acid, olenaolic acid, ursolic acid, phytol, α-ionone and ß-ionone. The three triterpenic acids and ß-ionone showed inhibitory activities on GAPDH with oleanolic acid being the most active with an inhibition of 72.63% at 20 µg/ml. This paper reports for the first time the composition and antitrypanosomal activity of the essential oil of Keetia leucantha. Several of its constituents and three triterpenic acids present in the dichloromethane leaves extract showed a higher antitrypanosomal activity on bloodstream forms of Tbb as compared to procyclic forms, namely geranyl acetone, phytol, α-ionone, ß-ionone, ursolic acid, oleanolic acid and betulinic acid. The four last compounds were proven to be inhibitors of trypanosomal GAPDH, which may in part explain these antitrypanosomal activities.
Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Óleos Voláteis/química , Rubiaceae/química , Tripanossomicidas/isolamento & purificação , Trypanosoma brucei brucei/enzimologia , Testes de Sensibilidade Parasitária , Fitoterapia , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais/químicaRESUMO
The Mallotus genus comprises numerous species used as traditional medicines in oriental countries and provides scientists a broad basis in the search for pharmacologically active constituents. In this paper, the cytotoxicity of 39 Mallotus extracts, different in species, part of the plant used, origin, and harvest season, is evaluated combining cytotoxicity assays with fingerprint technology and data handling tools. At first, the antiproliferative activity of the plant extracts is analyzed both on a non-cancerous cell line (WI-38--human lung fibroblast) and on a cancerous cell line (HeLa human cervix carcinoma). The results are linked to a data set of high-performance liquid chromatographic fingerprint profiles of the samples using multivariate calibration techniques. The regression coefficients of the multivariate model are then evaluated to indicate those peaks potentially responsible for the cytotoxic activity of the Mallotus extracts. In a final step, the cytotoxic extracts are analyzed by HPLC-MS and the indicated peaks identified.
Assuntos
Mallotus (Planta)/química , Extratos Vegetais/análise , Extratos Vegetais/toxicidade , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Avaliação Pré-Clínica de Medicamentos , Humanos , Mallotus (Planta)/classificação , Espectrometria de Massas/métodos , Análise Multivariada , Estações do AnoRESUMO
The aim of this work is to develop the first validated UHPLC-PDA method for major anthocyanins quantification in Euterpe oleracea fruits after fast extraction procedures and samples preparation. The separation was performed on HSS C18 column (1.8 µm) using a gradient elution with acetonitrile and 5% formic acid in a total run time of only 17 min. Total error and accuracy profiles were used as criteria for the validation process. Calibration in the matrix was found to be more accurate than calibration without matrix. Trueness (<6.76% relative bias), repeatability (<4.6% RSD), intermediate precision (<5.3% RSD), selectivity, response function and linearity for major anthocyanins, cyanidin-3-glucoside and cyanidin-3-rutinoside, were evaluated. The concentration range validated was 1-48 µg/mL for both compounds. In addition two cyanidin-di-O-glycosides were detected for the fist time in this fruit. We also showed that a first extraction of the fruits with ethyl acetate removes the lipophilic compounds and allows an easier extraction by methanol and quantification of anthocyanins in this extract.
Assuntos
Antocianinas/análise , Arecaceae/química , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Calibragem , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
The genera of Mallotus and Phyllanthus contain several species that are commonly used as traditional medicines in oriental countries. Some species show interesting pharmaceutical activities, such as an antioxidant activity. To produce clinically useful medicines or food supplements (nutraceuticals) from these herbs, the species should be identified and a thorough quality control should be implemented. Nowadays, the integration of chromatographic and chemometric approaches allows a high-throughput identification and activity prediction of medicinal plants. In this study, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were applied and compared to distinguish Mallotus and Phyllanthus species. Moreover, peaks from their chromatographic fingerprints, which were responsible for their antioxidant activity were assigned. For the latter purpose, the relevant information was extracted from the chromatographic fingerprints using linear multivariate calibration techniques, i.e., Partial Least Squares (PLS) and Orthogonal Projections to Latent Structures (O-PLS). Results reveal that exploratory analysis using PCA shows somewhat diverging clustering tendencies between Mallotus and Phyllanthus samples than HCA. However, both approaches mainly confirm each other. Concerning the multivariate calibration techniques, both PLS and O-PLS models demonstrate good predictive abilities. By comparing the regression coefficients of the models with the chromatographic fingerprints, the peaks that are potentially responsible for the antioxidant activity of the extracts could be confirmed.
Assuntos
Antioxidantes/análise , Mallotus (Planta)/química , Phyllanthus/química , Extratos Vegetais/análise , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Análise dos Mínimos Quadrados , Análise de Componente PrincipalRESUMO
Some Mallotus species are commonly used as traditional medicine (TM) ingredients in Vietnam and China, but only a few are studied for their activities. In Part I, high-performance liquid chromatography (HPLC) fingerprints of 39 Mallotus samples (17 species) were developed and, because of the complexity of and the large differences between the samples, it was chosen to analyse the unaligned fingerprints. The peaks, potentially responsible for the antioxidant activity in given Mallotus species, were indicated by the regression coefficients from an orthogonal projections to latent structures (O-PLS) model. In the present study, an in depth discussion on the need for alignment of the Mallotus fingerprints for the indication of the potentially active compounds is made, as well as an experimental analysis and identification of the previously indicated peaks by HPLC-mass spectrometry (HPLC-MS). Additionally, to thoroughly study and discuss the alignment problem, the modelling and prediction of the antioxidant activity of green tea samples based on HPLC fingerprints were also considered.
Assuntos
Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Mallotus (Planta)/química , Espectrometria de Massas , Medicina Tradicional , Análise de Componente Principal , Chá/químicaRESUMO
The genus of Mallotus contains several species commonly used as traditional medicines in oriental countries. A data set containing 39 Mallotus samples, differing in species, cultivation conditions, harvest season and/or part of the plant was used to develop fingerprints on two dissimilar chromatographic systems. An exploratory analysis with principal component analysis (PCA) was performed on both data sets individually. The results were also combined to obtain additional information on the unknown samples included in the data set. Furthermore, the antioxidant activity of the samples was measured and modelled as a function of the fingerprints using the orthogonal projections to latent structures (O-PLS) technique. The regression coefficients of the models were studied to indicate the peaks potentially responsible for the antioxidant activity. The indicated peaks were analyzed and identified by HPLC coupled to mass spectrometry (HPLC-MS). Because of the complexity of biological samples, it was aspired to separate co-eluting components based on the significant difference in chromatographic selectivity on the dissimilar systems and consequently obtain additional, complementary information on the contribution of the individual components to the antioxidant activity. The results illustrate the potential use of dissimilar chromatographic systems. Several initially co-eluting compounds could be separated on the dissimilar system. The corresponding regression coefficients provided complementary information on the potential antioxidant activity of the separated compounds.
Assuntos
Antioxidantes/análise , Cromatografia/métodos , Mallotus (Planta)/química , Métodos Analíticos de Preparação de Amostras , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão , Análise dos Mínimos Quadrados , Picratos/química , Extratos Vegetais/química , Análise de Componente PrincipalRESUMO
Some Mallotus species are used in traditional medicine in Vietnam and China. Some also show interesting activities, such as antioxidant and cytotoxic ones. Combining fingerprint technology with data-handling techniques allows indicating the peaks potentially responsible for given activities. In this study it is aspired to indicate from chromatographic fingerprints the peaks potentially responsible for the antioxidant activity of several Mallotus species. Relevant information was extracted using linear multivariate calibration techniques, both before and after alignment of the fingerprints with correlation optimized warping (COW). From the studied techniques, stepwise multiple linear regression is least recommended as it made an inadequate variable selection. Principal component regression theoretically can take largely varying variables uncorrelated to the antioxidant activity into account. However, in practice in the actual case study this problem was limited. These problems in principle do not occur using partial least squares (PLS) models. Of the tested PLS methods, orthogonal projections to latent structures was preferred because of its simplicity, reproducibility, reduced model complexity and improved interpretability of the regression coefficients, yielding a clearer view on the individual contribution of the compounds. Furthermore, reducing analysis times from 60min to 35 and 22.5min resulted in the same main compounds, indicated responsible for the antioxidant activity. Models built after alignment by COW did not result in additional information.
RESUMO
Some Mallotus species are used in traditional medicine in Vietnam and China. Some also show interesting activities, such as antioxidant and cytotoxic ones. Combining fingerprint technology with data-handling techniques allows indicating the peaks potentially responsible for given activities. In this study it is aspired to indicate from chromatographic fingerprints the peaks potentially responsible for the antioxidant activity of several Mallotus species. Relevant information was extracted using linear multivariate calibration techniques, both before and after alignment of the fingerprints with correlation optimized warping (COW). From the studied techniques, Stepwise Multiple Linear Regression is least recommended as it made an inadequate variable selection. Principal Component Regression theoretically can take largely varying variables uncorrelated to the antioxidant activity into account. However, in practice in the actual case study this problem was limited. These problems in principle do not occur using Partial Least Squares (PLS) models. Of the tested PLS methods, Orthogonal Projections to Latent Structures was preferred because of its simplicity, reproducibility, reduced model complexity and improved interpretability of the regression coefficients, yielding a clearer view on the individual contribution of the compounds. Furthermore, reducing analysis times from 60 min to 35 and 22.5 min resulted in the same main compounds, indicated responsible for the antioxidant activity. Models built after alignment by COW did not result in additional information.
Assuntos
Antioxidantes/análise , Cromatografia Líquida de Alta Pressão/normas , Mallotus (Planta)/química , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Análise dos Mínimos Quadrados , Análise Multivariada , Plantas Medicinais/química , Análise de Componente PrincipalRESUMO
Some Mallotus species are used in traditional medicine in Vietnam. To use certain species in Western medicines or as food supplements, they should be identified and quality control should be more strict, for instance, to avoid the erroneous switching of species. In species with interesting activities, the compounds responsible for them should be identified. For these identifications, HPLC fingerprint methodology can be used. In this paper, HPLC fingerprints of different lengths were developed for a number of Mallotus species. Secondly, a multivariate regression model was constructed to model the antioxidant activity of the Mallotus samples from the HPLC fingerprints with the aim to indicate peaks possibly responsible for this activity. For this purpose, after data pretreatment, the calibration technique partial least squares (PLS) was applied.
Assuntos
Antioxidantes/análise , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Mallotus (Planta)/metabolismo , Extratos Vegetais/análise , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Calibragem , Cromatografia/métodos , Suplementos Nutricionais , Radicais Livres , Indicadores e Reagentes/análise , Indicadores e Reagentes/isolamento & purificação , Análise dos Mínimos Quadrados , Análise Multivariada , Picratos/química , Extratos Vegetais/isolamento & purificação , Análise de Componente Principal , Tecnologia Farmacêutica/métodosRESUMO
The simultaneous quantification of madecassoside, asiaticoside, madecassic acid and asiatic acid in Centella asiatica by HPLC-UV is proposed. Asiaticoside was used as reference for the quantification of heterosides and asiatic acid for aglycones. The evaluation of the extraction efficiency of the four molecules led to use Soxhlet extraction for 8 h. The method was validated and was found to be accurate in the concentration range of 1.0-3.0 mg/ml for asiaticoside and 0.5-2.0 mg/ml for asiatic acid with CV <3% for all investigated compounds. LOD and LOQ were, respectively, 0.0113 and 1.0 mg/ml for asiaticoside and 0.0023 and 0.5 mg/ml for asiatic acid. This method was shown to be convenient for routine analysis of samples of C. asiatica.
Assuntos
Centella/química , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos/análise , Triterpenos/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Folhas de Planta/químicaRESUMO
Fungal endophytes were isolated from leaves of Centella asiatica (Apiaceae) collected at Mangoro (middle eastern region of Madagascar, 200 km from Antananarivo). Forty- five different taxa were recovered. The overall foliar colonization rate was 78%. The most common endophytes were the non-sporulating species 1 (isolation frequency IF 19.2%) followed by Colletotrichum sp.1 (IF 13.2%), Guignardia sp. (IF 8.5%), Glomerella sp. (IF 7.7%), an unidentified ascomycete (IF 7.2%), the non-sporulating species 2 (IF 3.7%) and Phialophora sp. (IF 3.5%). Using sequences of the ribosomal DNA internal transcribed spacer (ITS) regions, major endophytes (IF > 7%) were identified as xylariaceous taxa or as Colletotrichum higginsianum, Guignardia mangiferae and Glomerella cingulata. Results from in vitro fungal disk experiments showed a strong inhibitory activity of the xylariaceous non-sporulating species 1 against G. mangiferae and C. higginsianum and of C. higginsianum against G. mangiferae. This can be explained by antagonism between dominant taxa.
Assuntos
Ascomicetos/genética , Centella/microbiologia , Folhas de Planta/microbiologia , Ascomicetos/classificação , Colletotrichum/classificação , Colletotrichum/genética , DNA Espaçador Ribossômico/genética , Dados de Sequência Molecular , Análise de Sequência de DNARESUMO
Alchornea cordifolia is one of the most widely-used plants in traditional medicine throughout Africa, principally for inflammatory, antimicrobial and parasitic diseases. In continuation of our investigations on its anti-inflammatory activity, we fractionated the leaf and root bark extracts and isolated six compounds which exhibited significant topical anti-inflammatory activity in the mouse ear oedema model using croton oil at a dose of 90 microg/cm2. Daucosterol (2), acetyl aleuritolic acid (4), N1,N2-diisopentenyl guanidine (5) and N1,N2,N3-triisopentenyl guanidine (6) were shown to be more active than indomethacin, while beta-sitosterol (1) and di(2-ethylhexyl) phthalate (3) were less effective. This is the first report on the presence of compounds 1, 2, 3 and 4 in this plant and of the anti-inflammatory activity of 3, 5 and 6. These compounds may account, at least in part, for the use of A. cordifolia in folk medicine to treat inflammation.
Assuntos
Anti-Inflamatórios/farmacologia , Euphorbiaceae/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Modelos Animais de Doenças , Orelha , Edema/induzido quimicamente , Edema/tratamento farmacológico , Inflamação/tratamento farmacológico , Masculino , Medicinas Tradicionais Africanas , Camundongos , Extratos Vegetais/química , Folhas de Planta , Raízes de PlantasRESUMO
BACKGROUND: Trachylobane diterpenes are secondary metabolites, quite rare in nature, and their bioactivities are poorly understood. Recently, we have described the cytotoxic activity of ent-trachyloban-3beta-ol isolated from the leaves of Croton zambesicus, a plant used in African folk medicine. MATERIALS AND METHODS: Cell viability on several cell lines, cell morphology, DNA laddering, annexin Vand caspase-3 activation experiments were undertaken in order to analyse the cytotoxicty of trachylobane diterpene and to determine if this compound is able to induce apoptosis. RESULTS: ent-Trachyloban-3beta-ol exerts a dose-dependent cytotoxic effect, which varies between cell lines. Induction of apoptosis in HL-60 cells could be detected at a concentration of 50 microM after 24-h treatment. CONCLUSION: We show here, for the first time, that a trachylobane diterpene is able to induce apoptosis in human promyelocytic leukemia cells via caspase-3 activation in a concentration-dependent manner.
Assuntos
Apoptose/efeitos dos fármacos , Diterpenos/farmacologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Caspase 3 , Caspases/metabolismo , Croton/química , Ativação Enzimática/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Fosfatidilserinas/metabolismoRESUMO
Aporphinoids form an important group of plant secondary metabolites. Some of these compounds are used for a long time in traditional medicine for the treatment of various diseases, from benign syndromes to more severe illnesses. More than 500 aporphine alkaloids have been isolated from various plant families and many of these compounds display potent cytotoxic activities which may be exploited for the design of anticancer agents. Here we review the origin, biosynthesis, structure and cytotoxic properties of the prominent members of this class of compounds. Simple aporphinoids (boldine, dicentrine) as well as oxo-, pro- and dehydro-aporphines, and dimeric forms such as thalicarpine, are discussed here. Their mechanisms of action are not well known but DNA-manipulating enzymes such as polymerases and topoisomerases are among the most frequently cited targets for these benzylisoquinoline compounds. This review presents an updated view of the cytotoxic properties of the aporphinoids and their potential contribution to the development of anticancer agents.
Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Aporfinas/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Aporfinas/química , Aporfinas/isolamento & purificação , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Desenho de Fármacos , Humanos , Estrutura MolecularRESUMO
Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg. (Euphorbiaceae) is a widely distributed plant in Africa. It is used in the traditional medicine of many African countries for the treatment of bacterial, fungal, parasitic and inflammatory disorders. Aqueous decoction and methanol leaf extracts were tested for their ability to reduce Croton oil-induced oedema in the mouse ear, after topical application. The methanol leaf extract dose-dependently inhibited the Croton oil-induced ear oedema in mice (ID(50)<500 microg/cm(2)). A bio-assay guided liquid-liquid fractionation of this methanol extract gave four active fractions: water insoluble (F1), hexane (F2), ethyl acetate (F3) and water (F4). The hexane fraction showed a very high activity (42% inhibition at 0.7 microg/cm(2)) as compared to the control. The other fractions were less active (F1: 56% at 506.2 microg/cm(2); F3: 57% at 289.3 microg/cm(2); F4: 32% for 203.8 microg/cm(2)) while indomethacin gave 49% of inhibition at 90 microg/cm(2). The activity of F1 and F3 may be at least in part explained by the presence of anti-inflammatory flavonoids (hyperoside and quercitrin, quercitrin being identified in the plant for the first time) while the activity was not correlated to the tannin contents. None of these compounds were detected in the most active F2 fraction. These results support the reported traditional use of this plant against topical inflammatory disorders.