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1.
Int J Mol Sci ; 24(4)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36835085

RESUMO

Epigenetic mechanisms such as microRNA (miRNA) deregulation seem to exert a central role in breast cancer initiation and progression. Therefore, targeting epigenetics deregulation may be an effective strategy for preventing and halting carcinogenesis. Studies have revealed the significant role of naturally occurring polyphenolic compounds derived from fermented blueberry fruits in cancer chemoprevention by modulation of cancer stem cell development through the epigenetic mechanism and regulation of cellular signaling pathways. In this study, we first investigated the phytochemical changes during the blueberry fermentation process. Fermentation favored the release of oligomers and bioactive compounds such as protocatechuic acid (PCA), gallic acid, and catechol. Next, we investigated the chemopreventive potentials of a polyphenolic mixture containing PCA, gallic acid, and catechin found in fermented blueberry juice in a breast cancer model by measuring miRNA expression and the signaling pathways involved in breast cancer stemness and invasion. To this end, 4T1 and MDA-MB-231 cell lines were treated with different doses of the polyphenolic mixture for 24 h. Additionally, female Balb/c mice were fed with this mixture for five weeks; two weeks before and three weeks after receiving 4T1 cells. Mammosphere formation was assayed in both cell lines and the single-cell suspension obtained from the tumor. Lung metastases were counted by isolating 6-thioguanine-resistant cells present in the lungs. In addition, we conducted RT-qPCR and Western blot analysis to validate the expression of targeted miRNAs and proteins, respectively. We found a significant reduction in mammosphere formation in both cell lines treated with the mixture and in tumoral primary cells isolated from mice treated with the polyphenolic compound. The number of colony-forming units of 4T1 cells in the lungs was significantly lower in the treatment group compared to the control group. miR-145 expression significantly increased in the tumor samples of mice treated with the polyphenolic mixture compared to the control group. Furthermore, a significant increase in FOXO1 levels was noted in both cell lines treated with the mixture. Overall, our results show that phenolic compounds found in fermented blueberry delay the formation of tumor-initiating cells in vitro and in vivo and reduce the spread of metastatic cells. The protective mechanisms seem to be related, at least partly, to the epigenetic modulation of mir-145 and its signaling pathways.


Assuntos
Mirtilos Azuis (Planta) , Neoplasias da Mama , MicroRNAs , Polifenóis , Animais , Feminino , Camundongos , Mirtilos Azuis (Planta)/química , Linhagem Celular Tumoral , Proliferação de Células , Quimioprevenção , Fermentação , Ácido Gálico/farmacologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/efeitos dos fármacos , MicroRNAs/metabolismo , Polifenóis/farmacologia , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/metabolismo , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo
2.
Phytother Res ; 32(4): 705-714, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29377302

RESUMO

Perturbations to extravillous trophoblast (EVT) cell migration and invasion are associated with the development of placenta-mediated diseases. Phytochemicals found in the lowbush blueberry plant (Vaccinium angustifolium) have been shown to influence cell migration and invasion in models of tumorigenesis and noncancerous, healthy cells, however never in EVT cells. We hypothesized that the phenolic compounds present in V. angustifolium leaf extract promote trophoblast migration and invasion. Using the HTR-8/SVneo human EVT cell line and Boyden chamber assays, the influence of V. angustifolium leaf extract (0 to 2 × 104  ng/ml) on trophoblast cell migration (n = 4) and invasion (n = 4) was determined. Cellular proliferation and viability were assessed using immunoreactivity to Ki67 (n = 3) and trypan blue exclusion assays (n = 3), respectively. At 20 ng/ml, V. angustifolium leaf extract increased HTR-8/SVneo cell migration and invasion (p < .01) and did not affect cell proliferation or viability. Chlorogenic acid was identified as a major phenolic compound of the leaf extract and the most active compound. Evidence from Western blot analysis (n = 3) suggests that the effects of the leaf extract and chlorogenic acid on trophoblast migration and invasion are mediated through an adenosine monophosphate-activated protein (AMP) kinase-dependent mechanism. Further investigations examining the potential therapeutic applications of this natural health product extract and its major chemical compounds in the context of placenta-mediated diseases are warranted.


Assuntos
Mirtilos Azuis (Planta)/química , Movimento Celular/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Trofoblastos/metabolismo
3.
Planta Med ; 82(14): 1302-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27163231

RESUMO

Sorbus decora and Sorbus americana are used traditionally as medicine by the Eeyou Istchee Cree First Nation of the James Bay region of Quebec, Canada. Because the ethanol extracts of the bark and the isolated terpenes of these plants have shown promising in vivo antidiabetic effects, an analytical method was developed and validated by RP-HPLC-ELSD for the identification and quantification of eight lupane- and ursane-type terpenes. The extraction method reproducibly recovered the compounds above 70 % and the chromatographic separation of betulin, 23-hydroxy-betulin, 23,28-dihydroxylupan-20(29)-ene-3ß-caffeate, betulinic acid, α-amyrin, uvaol, 3ß,23,28-trihydroxy-12-ursene, and 23,28-dihydroxyursan-12-ene-3ß-caffeate was achieved within 27 min by linear gradient. The method produced highly reproducible quantitative data at interday and intraday levels. The limits of detection were in the ng level on-column with remarkable range and linearity. The target compounds were present at mg levels in the populations, collected from inland (Mistissini and Nemaska) and costal (Waskagnish and Chisasibi) Cree communities of northern Quebec. A triterpene, 23-hydroxybetulin, was the most abundant, while betulinic acid and uvaol were minor constituents. Overall, HPLC-ELSD analyses produced very similar profiles and contents of the eight compounds in the plants collected from four geographic locations. The developed HPLC-ELSD method can be used as a targeted analysis of triterpenes in these medicinal plants.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Sorbus/química , Triterpenos/isolamento & purificação , Canadá , Humanos , Indígenas Norte-Americanos , Luz , Estrutura Molecular , Casca de Planta/química , Espalhamento de Radiação , Triterpenos/química
4.
Molecules ; 21(1): E29, 2015 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-26712734

RESUMO

Microbial biofilms readily form on many surfaces in nature including plant surfaces. In order to coordinate the formation of these biofilms, microorganisms use a cell-to-cell communication system called quorum sensing (QS). As formation of biofilms on vascular plants may not be advantageous to the hosts, plants have developed inhibitors to interfere with these processes. In this mini review, research papers published on plant-derived molecules that have microbial biofilm or quorum sensing inhibition are reviewed with the objectives of determining the biosynthetic classes of active compounds, their biological activity in assays, and their families of occurrence and range. The main findings are the identification of plant phenolics, including benzoates, phenyl propanoids, stilbenes, flavonoids, gallotannins, proanthocyanidins and coumarins as important inhibitors with both activities. Some terpenes including monoterpenes, sesquiterpenes, diterpenes and triterpenes also have anti-QS and anti-biofilm activities. Relatively few alkaloids were reported. Quinones and organosulfur compounds, especially from garlic, were also active. A common feature is the polar nature of these compounds. Phytochemicals with these activities are widespread in Angiosperms in temperate and tropical regions, but gymnosperms, bryophytes and pteridophytes were not represented.


Assuntos
Biofilmes/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Percepção de Quorum/efeitos dos fármacos , Traqueófitas/química , Antibacterianos/farmacologia , Monoterpenos/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia
5.
J Pharm Pharm Sci ; 17(3): 294-301, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25224344

RESUMO

PURPOSE: Thirty-five commercially available Camellia sinensis (black and green) and herbal leisure teas and an assortment of Traditional Chinese medicinal teas were randomly selected and examined for their potential to inhibit the drug metabolizing enzyme cytochrome P450 3A4 (CYP3A4). The study was then extended to examine CYP2D6*1 and CYP2D6*10. METHODS: Microtiter fluorometric assays were utilized to examine the potential for the teas to inhibit CYP-mediated metabolism. Aqueous or alcoholic extracts of the dried tea plant material were examined. METHODS: Most of the black and green leisure teas generally inhibited CYP3A4 more than the Chinese medicinal teas. The medicinal Chinese teas were generally more inhibitory towards CYP3A4 compared to the CYP2D6 isozymes, and the aqueous extracts displayed more potency than the alcoholic extracts. CONCLUSIONS: Tea whether used for leisure or medicinal purposes has the potential to inhibit CYP3A4-mediated drug metabolism particularly black tea.


Assuntos
Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Inibidores das Enzimas do Citocromo P-450/farmacologia , Chá/química , Camellia sinensis/química , Camellia sinensis/metabolismo , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/metabolismo , Medicina Tradicional Chinesa , Relação Estrutura-Atividade , Chá/metabolismo
6.
Annu Rev Entomol ; 57: 405-24, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21942843

RESUMO

In recent years, the use of essential oils (EOs) derived from aromatic plants as low-risk insecticides has increased considerably owing to their popularity with organic growers and environmentally conscious consumers. EOs are easily produced by steam distillation of plant material and contain many volatile, low-molecular-weight terpenes and phenolics. The major plant families from which EOs are extracted include Myrtaceae, Lauraceae, Lamiaceae, and Asteraceae. EOs have repellent, insecticidal, and growth-reducing effects on a variety of insects. They have been used effectively to control preharvest and postharvest phytophagous insects and as insect repellents for biting flies and for home and garden insects. The compounds exert their activities on insects through neurotoxic effects involving several mechanisms, notably through GABA, octopamine synapses, and the inhibition of acetylcholinesterase. With a few exceptions, their mammalian toxicity is low and environmental persistence is short. Registration has been the main bottleneck in putting new products on the market, but more EOs have been approved for use in the United States than elsewhere owing to reduced-risk processes for these materials.


Assuntos
Controle de Insetos , Insetos , Óleos Voláteis , Animais , Meio Ambiente , Óleos Voláteis/química , Óleos Voláteis/toxicidade , Plantas/química , Controle Social Formal
7.
Can J Physiol Pharmacol ; 90(2): 167-74, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22320845

RESUMO

Eight commercial grape seed products (GSPs) were assessed for their inhibition of the formation of advanced glycation end-products in vitro. All 8 commercial GSPs included in this study were potent inhibitors of advanced glycation end-product formation with IC(50) values ranging from 2.93 to 20.0 µg/mL. Total procyanidin content ranged from 60% to 73%. HPLC-DAD-ELSD results indicate that (+)-catechin, (-)-epicatechin, procyanidin B1, and procyanidin B2 were predominant and ubiquitously present in all the products under study, while gallic acid and procyanidin B4 were present in relatively minor amounts. The IC(50) values correlated with total phenolic content, and multiple regression analysis indicated that IC(50) is a linear function of the concentration of gallic acid and procyanidins B1, B2, and B4. Based on this study, GSPs have the potential to complement conventional diabetes medication toward disease management and prevention.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Extrato de Sementes de Uva/farmacologia , Hipoglicemiantes/farmacologia , Fenóis/farmacologia , Proantocianidinas/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Vitis , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Glicosilação , Extrato de Sementes de Uva/análise , Extrato de Sementes de Uva/isolamento & purificação , Hipoglicemiantes/análise , Hipoglicemiantes/isolamento & purificação , Modelos Lineares , Fenóis/análise , Fenóis/isolamento & purificação , Proantocianidinas/análise , Proantocianidinas/isolamento & purificação , Sementes , Espectrofotometria Ultravioleta , Vitis/química
8.
Front Pharmacol ; 13: 815742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295322

RESUMO

Traditionally the role of phytochemistry in the ethnopharmacology of North and Central America has been to characterize plant materials so that they can be produced reproducibly for commercial use or to identify active principles in unstudied traditional medicines for drug discovery. With new decolonial objectives coming from Indigenous communities, emphasis has shifted to evaluating the safety and efficacy of traditional medicines and preparations for community use. With new techniques and technologies available, scientific focus has shifted from individual bioactives to more rapid and comprehensive chemical characterizations and polypharmacy of traditional medicines. Untargeted metabolomics and associated statistical treatments have greatly expanded identification of components, improved species and cultivar identification and provided means for identifying multiple activity biomarkers, via chemometric and biochemometric analysis. New integrated techniques are available for identifying multiple active principles and synergists. The recent explosion of information is not without problems that need to be addressed including many unconfirmed tentative identifications of phytochemicals, lack of quantitative testing, superficial chemical activity testing and continuing need for dereplication.

9.
J Pharm Pharm Sci ; 14(1): 1-16, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21501549

RESUMO

PURPOSE: The use of supplements as herbal and micronutrient natural health products with conventional health products has become increasingly popular. It has been reported that some herbal products can inhibit the activity of cytochrome P450-mediated metabolism and drug disposition. This study was designed to investigate a case report of a severe adverse event to determine the potential interactions of femMED, Thyrosense and vitamins on cytochrome P450-mediated drug metabolism. METHODS: The effect of extracts from these commercially available herbal formulations, trans-ß-carotene, multivitamins, and vitamin D3 supplements on cytochrome P450-mediated drug metabolism of marker substrates was determined in vitro. RESULTS: The blended herbal products femMED and Thyrosense had a high potential to affect the safety and efficacy of many health products. Some vitamin and trans-ß-carotene containing products also have the potential to affect drug disposition. The tBC content of various products was analyzed and significant discrepancies were found among them and between values indicated on product labels. Product extracts also exhibited a low to moderate capacity to inhibit cytochrome P450 2C9, 2C19 and 3A4-mediated metabolism. CONCLUSIONS: The findings of this study suggest that these herbal products and most vitamin products may have an inhibitory effect on cytochrome P450 activity that could contribute to development of an adverse event. Further work is warranted to determine how supplementation with these products may affect drug metabolism in an in vivo context.


Assuntos
Inibidores das Enzimas do Citocromo P-450 , Inibidores Enzimáticos/efeitos adversos , Extratos Vegetais/efeitos adversos , Vitaminas/efeitos adversos , Adulto , Colecalciferol/efeitos adversos , Colecalciferol/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Suplementos Nutricionais , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Extratos Vegetais/farmacologia , Vitaminas/farmacologia , beta Caroteno/efeitos adversos , beta Caroteno/farmacologia
10.
Can J Microbiol ; 57(9): 745-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21859295

RESUMO

This study investigated the antibacterial activity of glycolipid-rich extracts of the brown macroalga Fucus evanescens in cell culture. Accessions were collected on the Arctic coast of Ungava Bay, Nunavik, Quebec. The crude ethyl acetate extract of these accessions showed strong antibacterial activity (≥4 log(10) cfu) against Hemophilus influenzae , Legionella pneumophila , Propionibacterium acnes (ATCC and clinical isolate), and Streptococcus pyogenes at 100 µg/mL. This algal extract inhibited by 3 log(10) Clostridium difficile and methicillin-resistant Staphylococcus aureus , whereas Bacillus cereus , Escherichia coli , Klebsiella pneumoniae , and Pseudomonas aeruginosa were not significantly affected. Further investigations of the activity of a glycolipid-rich fraction, extracted with dichloromethane, against Propionibacterium acnes showed an MIC(100) of 50 µg/mL, with an inhibition of more than 99% at only 7.8 µg/mL. The main active compound, a ß-d-galactosyl O-linked glycolipid, was synthesized for the bioassay and showed an MIC(100) of 50 µg/mL but lost its activity more quickly with only 50% of inhibition at 12.5 µg/mL. Therefore, the semipurified F. evanescens extract could be a good choice for future research into the development of alternative treatments for acne therapy.


Assuntos
Antibacterianos/farmacologia , Produtos Biológicos/farmacologia , Fucus/metabolismo , Acne Vulgar , Antibacterianos/metabolismo , Baías , Produtos Biológicos/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/crescimento & desenvolvimento , Haemophilus influenzae/isolamento & purificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/crescimento & desenvolvimento , Klebsiella pneumoniae/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Propionibacterium acnes/efeitos dos fármacos , Propionibacterium acnes/crescimento & desenvolvimento , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/isolamento & purificação , Quebeque , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/crescimento & desenvolvimento , Streptococcus pneumoniae/isolamento & purificação
11.
Phytother Res ; 25(2): 264-70, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20648677

RESUMO

The purpose of this work was to develop an extraction technique to yield a betulinic acid-(BA) enriched extract of the traditional anti-anxiety plant Souroubea sympetala Gilg (Marcgraviaceae). Five extraction techniques were compared: supercritical carbon dioxide extraction (SCE), conventional solvent extraction with ethyl acetate (EtOAc), accelerated solvent extraction (ASE), ultrasonic assisted extraction (UAE) and soxhlet extraction (Sox). The EtOAc and SCE extraction methods resulted in BA-enriched extracts, with BA concentrations of 6.78 ± 0.2 and 5.54 ± 0.2 mg/g extract, respectively, as determined by HPLC-APCI-MS. The bioactivity of the BA-enriched extracts was compared in the elevated plus maze (EPM), a validated rodent anxiety behaviour assay. Rats orally administered a 75 mg/kg dose of SCE extract exhibited anxiolysis as compared with vehicle controls, with a 50% increase in the percent time spent in the open arms, a 73% increase in unprotected head dips and a 42% decrease in percent time spent in the closed arms. No significant differences were observed between the SCE and EtOAc extracts for these measures, but the animals dosed with SCE extract had significantly more unprotected head dips than those dosed with the EtOAc extract. The SCE extract demonstrated a dose-response in the EPM, with a trend toward decreased anxiety at 25 mg/kg, and significant anxiolysis was only observed at 75 mg/kg dose. This study demonstrates that SCE can be used to generate a betulinic acid-enriched extract with significant anxiolysis in vivo. Further, the study provides a scientific basis for the ethnobotanical use of this traditional medicine and a promising lead for a natural health product to treat anxiety.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Animais , Comportamento Exploratório/efeitos dos fármacos , Magnoliopsida/química , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Triterpenos Pentacíclicos , Ratos , Ratos Sprague-Dawley , Ácido Betulínico
12.
Front Pharmacol ; 12: 651292, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33986678

RESUMO

Historical ethnobotanies of indigenous peoples of the North American prairies reveal treatment of many painful conditions by Echinacea spp. Recent evidence suggests a pharmacological basis for such use as the bioactivity of E. angustifolia and E. purpurea is mediated, in part, through activation of the endocannabinoid system (ECS). Whereas the cannabimimetic effects of individual echinacea products and alkylamides have been described, the activity of crude extracts has not been compared between cannabinoid (CB) receptors or across species or genotypes. Moreover, few studies have explored echinacea's engagement of the ECS for historic treatments or new therapeutic applications in peripheral inflammatory pain. We hypothesized that 1) the in vitro effects of root extracts on CB receptor internalization would vary with species and phytochemistry, and that echinacea root extracts would reduce inflammatory pain in vivo through activation of the ECS. Root extracts of different E. angustifolia and E. purpurea accessions were prepared, analyzed by HPLC-DAD to quantify caffeic acid derivatives and alkylamides (AKA), and tested for agonist and antagonist activities using receptor redistribution assays. Linear regression of activity relative to phytochemistry identified predictive compounds that were assessed individually in redistribution assays. Extracts were evaluated in the Hargreaves model of chronic inflammatory pain in rats with co-administration of selective CB1/2 antagonists to gauge involvement of the ECS. CB receptor agonist activity varied among accessions of both species with linear regression revealing a significant relationship between CB1 activity and AKA2 for E angustifolia, and AKA 9 + 10 for E purpurea. CB2 activity was positively related with AKA 9 + 10 and total AKAs in E. angustifolia. Four isolated AKA demonstrated agonist activity in the CB2, but not CB1, assay. In the inflammatory pain model, oral administration of either E angustifolia or E. purpurea root extract produced dose-dependent analgesic effects that were partially reversed by co-administration of CB receptor antagonists. This study demonstrates that in vitro effects of crude echinacea root extracts on CB receptors is predicted by phytochemistry. In vivo, echinacea has potential applications for peripheral inflammatory pain such as arthritis and burns, reflecting the traditional uses of Indigenous North Americans.

13.
J Nat Prod ; 73(9): 1519-23, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20738101

RESUMO

Bioassay-guided fractionation of a crude extract (80% EtOH in H(2)O) of stem bark of Sorbus decora led the isolation of three new pentacycle triterpenes (compounds 1-3). The structures of 1-3 were established on the basis of spectroscopic methods (IR, HREIMS, 1D and 2D NMR) as 23,28-dihydroxyursan-12-ene-3ß-caffeate, 23,28-dihydroxylupan-20(29)-ene-3ß-caffeate, and 3ß,23,28-trihydroxy-12-ursene, respectively. Compound 2 significantly enhanced glucose uptake in C2C12 cells, but compounds 1 and 3 did not. In addition, triterpenoids 4-8, catechin, and epicatechin were also isolated. This is the first comprehensive report of the phytochemical constituents of S. decora since the initial study by Narashmachari and von Rudloff (1962) and includes evaluation of their antidiabetic activity.


Assuntos
Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Sorbus/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Animais , Hipoglicemiantes/química , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Caules de Planta/química , Quebeque , Estereoisomerismo , Triterpenos/química
14.
Phytochem Anal ; 20(5): 395-401, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19609882

RESUMO

INTRODUCTION: Commercially available herbal mixture FE, a proprietary natural health product manufactured by Flora Manufacturing and Distributing Ltd (Flora), is a unique North American traditional herbal product. FE is a chemically complex mixture of eight herbs and has not been subjected to phytochemical analysis. OBJECTIVE: To develop analytical methods to undertake detailed phytochemical analyses of FE, and its eight contributing herbs, including burdock (Arctium lappa L.), sheep sorrel (Rumex acetosella L.), Turkish rhubarb (Rheum palmatum L.), slippery elm Muhl. (Ulmus rubra), watercress (Nasturtium officinale R. Br.), red clover (Trifolium pratense L.), blessed thistle (Cnicus benedictus L.) and kelp (Laminaria digitata Lmx.). METHODOLOGY: The identification was undertaken by a combination of reversed phase high performance liquid chromatography-diode array detection-atmospheric pressure chemical ionisation-mass selective detection (RP-HPLC-DAD-APCI-MSD) analysis and phenolics metabolomic library matching. RESULTS: New separation methods facilitated the identification of 43 markers in the individual herbs which constitute FE. Sixteen markers could be identified in FE originating from four contributing herbs including four caffeoyl quinic acids, three dicaffeoyl quinic acids and two caffeic acid derivatives from A. lappa, luteolin-7-O-glucoside, luteolin, five apigenin glycosides and apigenin from R. acetocella and N. officinale and sissostrin from T. pretense. A validated method for quantitative determination of three markers is reported with good intraday, interday and interoperator repeatability using a reliable alcohol based extraction technique. CONCLUSION: FE and its contributing herbs predominantly contain phenolics. This methodology can be applied to further develop full-scale validation of this product.


Assuntos
Produtos Biológicos/química , Medicamentos de Ervas Chinesas/química , Laminaria/química , Fenóis/análise , Plantas Medicinais/química , Apigenina/análise , Arctium/química , Ácidos Cafeicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cnicus/química , Glicosídeos/análise , Luteolina/análise , Nasturtium/química , Fenóis/química , Ácido Quínico/análise , Reprodutibilidade dos Testes , Rheum/química , Rumex/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Trifolium/química , Ulmus/química
15.
ACS Omega ; 4(6): 10915-10920, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31460189

RESUMO

Synthesis of 50 analogues of the natural insecticide synergists, dillapiol and sesamol, is reported. These were evaluated as potential insecticide synergists based on their inhibition of human CYP3A4. The most potent inhibitors have a relatively large hydrophobic substituent at either position 5 or 6 of these molecules. For example, 5-(benzyloxy)-6-(3-phenylsulfonyl)propyl)benzo[d][1,3]dioxole (18) and the diphenyl acetate of (6,7-dimethoxybenzo[d][1,3]dioxol-5-yl)propan-1-ol (5n) show inhibitory concentrations for 50% activity IC50 values of 0.086 and 0.2 µM, respectively. These compounds are 106 and 46 times more potent than dillapiol whose IC50 for the inhibition of CYP3A4 is 9.2 µM. The ortho-chloro analogue (8f), whose activity is 86 times the activity of dillapiol, is the most potent of the fourteen 5-(benzyloxy-6-(2 propenyl)benzo[d][1,3]dioxoles prepared for this study.

16.
J Ethnopharmacol ; 109(3): 380-7, 2007 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-17071033

RESUMO

Selected plants used to treat susto, a folk illness recognized by various groups of Latin America, were screened for anxiolytic and/or fear suppression activity in behavioral assays. We found that the plant used by most of the healers interviewed (Adiantum tetraphyllum Humb. & Bonpl. ex Willd.; Adiantaceae) suppressed certain components of anxiety and fear. To our knowledge, this is the first report on the biological activity of Adiantum tetraphyllum. This finding supports the contention that susto may represent what in the Western culture is defined as fear or anxiety, and hence may share the same psychological, biological or neural underpinnings. In light of the available literature, this represents the first experimental investigation of the biological activity of plants specifically in the perspective of their use in treating a culture-bound syndrome.


Assuntos
Ansiedade/tratamento farmacológico , Medo/efeitos dos fármacos , Gleiquênias/química , Selaginellaceae/química , Animais , Belize , Etanol/química , Etnofarmacologia , Masculino , Transtornos Mentais/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Plantas Medicinais/química , Ratos , Ratos Sprague-Dawley
17.
J Agric Food Chem ; 54(4): 1289-95, 2006 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-16478250

RESUMO

Black pepper, Piper nigrum L. (Piperaceae), has insecticidal properties and could potentially be utilized as an alternative to synthetic insecticides. Piperine extracted from P. nigrum has a biphasic effect upon cytochrome P450 monooxygenase activity with an initial suppression followed by induction. In this study, an ethyl acetate extract of P. nigrum seeds was tested for insecticidal activity toward adult Musca domestica and Drosophila melanogaster. The effect of this same P. nigrum extract upon differential gene expression in D. melanogaster was investigated using cDNA microarray analysis of 7380 genes. Treatment of D. melanogaster with P. nigrum extract led to a greater than 2-fold upregulation of transcription of the cytochrome P450 phase I metabolism genes Cyp 6a8, Cyp 9b2, and Cyp 12d1 as well as the glutathione-S-transferase phase II metabolism gene Gst-S1. These data suggests a complex effect of P. nigrum upon toxin metabolism.


Assuntos
Drosophila melanogaster/genética , Perfilação da Expressão Gênica , Inseticidas/administração & dosagem , Piper nigrum/química , Alcaloides/farmacologia , Animais , Benzodioxóis , Northern Blotting , Inibidores das Enzimas do Citocromo P-450 , DNA Complementar/genética , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas
18.
Oncotarget ; 7(45): 73080-73100, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27564258

RESUMO

Dandelion extracts have been studied extensively in recent years for its anti-depressant and anti-inflammatory activity. Recent work from our lab, with in-vitro systems, shows the anti-cancer potential of an aqueous dandelion root extract (DRE) in several cancer cell models, with no toxicity to non-cancer cells. In this study, we examined the cancer cell-killing effectiveness of an aqueous DRE in colon cancer cell models. Aqueous DRE induced programmed cell death (PCD) selectively in > 95% of colon cancer cells, irrespective of their p53 status, by 48 hours of treatment. The anti-cancer efficacy of this extract was confirmed in in-vivo studies, as the oral administration of DRE retarded the growth of human colon xenograft models by more than 90%. We found the activation of multiple death pathways in cancer cells by DRE treatment, as revealed by gene expression analyses showing the expression of genes implicated in programmed cell death. Phytochemical analyses of the extract showed complex multi-component composition of the DRE, including some known bioactive phytochemicals such as α-amyrin, ß-amyrin, lupeol and taraxasterol. This suggested that this natural extract could engage and effectively target multiple vulnerabilities of cancer cells. Therefore, DRE could be a non-toxic and effective anti-cancer alternative, instrumental for reducing the occurrence of cancer cells drug-resistance.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Transdução de Sinais/efeitos dos fármacos , Taraxacum/química , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Modelos Animais de Doenças , Metabolismo Energético/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Artigo em Inglês | MEDLINE | ID: mdl-26508979

RESUMO

The traditional medicinal plant, Labrador tea (Rhododendron groenlandicum (Oeder) Kron & Judd; Ericaceae), present in the pharmacopoeia of the Cree of Eeyou Istchee, has shown glitazone-like activity in the 3T3-L1 adipogenesis bioassay. This activity has been attributed to phenolic compounds, which have been shown to vary in this plant as a function of insolation parameters. The goal of this study was to determine if these changes in phenolic content were pharmacologically significant. Leaves were harvested in 2006 throughout the James Bay region of Northern Quebec and ethanol extracts were tested in vitro using the 3T3-L1 murine cell line adipogenesis bioassay. This traditional medicinal plant was found active in the assay. However, there was no detectable spatial pattern in the accumulation of intracellular triglycerides, suggesting that such patterns previously observed in the phenolic profile of Labrador tea were not pharmacologically significant. Nonetheless, a reduction in the adipogenic activity was observed and associated with higher concentrations of quercetin for which selected environmental variables did not appropriately explain its variation.

20.
Artigo em Inglês | MEDLINE | ID: mdl-25883673

RESUMO

Natural health products (NHPs) are defined as natural extracts containing polychemical mixtures; they play a leading role in the discovery and development of drugs, for disease treatment. More than 50% of current cancer therapeutics are derived from natural sources. However, the efficacy of natural extracts in treating cancer has not been explored extensively. Scientific research into the validity and mechanism of action of these products is needed to develop NHPs as main stream cancer therapy. The preclinical and clinical validation of NHPs would be essential for this development. This review summarizes some of the recent advancements in the area of NHPs with anticancer effects. This review also focuses on various NHPs that have been studied to scientifically validate their claims as anticancer agents. Furthermore, this review emphasizes the efficacy of these NHPs in targeting the multiple vulnerabilities of cancer cells for a more selective efficacious treatment. The studies reviewed here have paved the way for the introduction of more NHPs from traditional medicine to the forefront of modern medicine, in order to provide alternative, safer, and cheaper complementary treatments for cancer therapy and possibly improve the quality of life of cancer patients.

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