Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Int J Mol Sci ; 24(4)2023 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-36835085

RESUMEN

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.


Asunto(s)
Arándanos Azules (Planta) , Neoplasias de la Mama , MicroARNs , Polifenoles , Animales , Femenino , Ratones , Arándanos Azules (Planta)/química , Línea Celular Tumoral , Proliferación Celular , Quimioprevención , Fermentación , Ácido Gálico/farmacología , Regulación Neoplásica de la Expresión Génica , MicroARNs/efectos de los fármacos , MicroARNs/metabolismo , Polifenoles/farmacología , Neoplasias Mamarias Animales/tratamiento farmacológico , Neoplasias Mamarias Animales/genética , Neoplasias Mamarias Animales/metabolismo , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo
2.
Front Pharmacol ; 13: 815742, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295322

RESUMEN

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.

3.
Front Pharmacol ; 12: 651292, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33986678

RESUMEN

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.

4.
ACS Omega ; 4(6): 10915-10920, 2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31460189

RESUMEN

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.

5.
Phytother Res ; 32(4): 705-714, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29377302

RESUMEN

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.


Asunto(s)
Arándanos Azules (Planta)/química , Movimiento Celular/efectos de los fármacos , Extractos Vegetales/química , Hojas de la Planta/química , Trofoblastos/metabolismo
6.
Oncotarget ; 7(45): 73080-73100, 2016 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-27564258

RESUMEN

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.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Extractos Vegetales/farmacología , Raíces de Plantas/química , Transducción de Señal/efectos de los fármacos , Taraxacum/química , Animales , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Modelos Animales de Enfermedad , Metabolismo Energético/efectos de los fármacos , Perfilación de la Expresión Génica , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/genética , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Planta Med ; 82(14): 1302-7, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27163231

RESUMEN

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.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Sorbus/química , Triterpenos/aislamiento & purificación , Canadá , Humanos , Indígenas Norteamericanos , Luz , Estructura Molecular , Corteza de la Planta/química , Dispersión de Radiación , Triterpenos/química
8.
Molecules ; 21(1): E29, 2015 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-26712734

RESUMEN

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.


Asunto(s)
Biopelículas/efectos de los fármacos , Fitoquímicos/farmacología , Percepción de Quorum/efectos de los fármacos , Tracheophyta/química , Antibacterianos/farmacología , Monoterpenos/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología
9.
Artículo en Inglés | MEDLINE | ID: mdl-26508979

RESUMEN

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.

10.
J Ethnopharmacol ; 173: 383-423, 2015 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-26234177

RESUMEN

ETHNOPHARMACOLOGICAL IMPORTANCE: The use of medicinal plants for treatment, cure and prevention of diseases has been described by many people since time immemorial. Because of this use, commercial and scientific interests have emerged, making it necessary to realize ethnobotanical surveys of medicinal plants species, which is important for subsequent chemical and pharmacological bioprospections. AIM OF THE STUDY: This study aimed at surveying, identifying, cataloging and documenting the medicinal plants species used in the Valley of Juruena, Northwestern Mato Grosso, Legal Amazon Brazil for the treatment of various human diseases, as well as assessed the species of interest for bioprospecting potential. MATERIALS AND METHODS: Informants were interviewed using semi-structured form to capture information on socio-demographic and ethnopharmacological data of medicinal plants such as vernacular name, uses, geographic origin, habit, form of preparation and part used. Results were analyzed using descriptive and quantitative means: indices of use-report (Ur) and informant consensus factor (ICF), for the selection of plant species with therapeutic potential. RESULTS: Three hundred and thirty two (332) plants species belonging to 90 families were reported for medicinal purposes and totaling 3973 use-reports were reported by 365 (92.9%) of the people interviewed. Asteraceae (32.2%), Fabaceae (26.7%) and Lamiaceae (24.4%) families were the most represented, with majority being species native (64.45%) to Brazil. Leaves (64.5%) were the part of the plant most used and infusion (45.7%) was the most utilized form. Gastrointestinal disorders followed by respiratory complaints topped the list of use-reports. The native or naturalized plants with the highest use reports in the order of decreasing absolute frequency per each emic-category are Cymbopogon citratus (DC.) Stapfc (104), Mentha pulegium L. (94), Arrabidaea chica (Humb. & Bonpl.) B. Verl. (97), Alternanthera brasiliana (L.) Kuntze (71), Baccharis crispa Spreng (57), Phyllanthus niruri L. (48), Gossypium barbadense L. (44), Solidago microglossa DC. (40) and Bauhinia forficata L. (20). And the most cited exotics are: Chenopodium ambrosioides L. (151), Aloe vera (L.) Burm. f., (89) and Rosmarinus officinalis L. (72). In some cases, high ICF values were found, which reflects high degree of homogeneity of consensus among informants in this region on medicinal plants. CONCLUSION: The population of Valle of Juruena makes use of a wide array of medicinal plants distributed in all use categories with predominance of those use in the treatments of gastrointestinal and respiratory ailments. The therapeutic potential of some of the species of medicinal importance extensively utilized by the population of the region have been scientifically validated, and are therefore promising prototype of new drugs. However, there are some of these species whose ethnomedicinal uses are yet to be scientifically verified and thus constitute an unexplored terrain for future biological/pharmacological studies.


Asunto(s)
Fitoterapia , Plantas Medicinales , Adulto , Brasil , Etnobotánica , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Medicina Tradicional , Persona de Mediana Edad , Encuestas y Cuestionarios
11.
Artículo en Inglés | MEDLINE | ID: mdl-25883673

RESUMEN

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.

12.
PLoS One ; 9(11): e113250, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25401766

RESUMEN

BACKGROUND: Currently chemotherapy is limited mostly to genotoxic drugs that are associated with severe side effects due to non-selective targeting of normal tissue. Natural products play a significant role in the development of most chemotherapeutic agents, with 74.8% of all available chemotherapy being derived from natural products. OBJECTIVE: To scientifically assess and validate the anticancer potential of an ethanolic extract of the fruit of the Long pepper (PLX), a plant of the piperaceae family that has been used in traditional medicine, especially Ayurveda and investigate the anticancer mechanism of action of PLX against cancer cells. MATERIALS & METHODS: Following treatment with ethanolic long pepper extract, cell viability was assessed using a water-soluble tetrazolium salt; apoptosis induction was observed following nuclear staining by Hoechst, binding of annexin V to the externalized phosphatidyl serine and phase contrast microscopy. Image-based cytometry was used to detect the effect of long pepper extract on the production of reactive oxygen species and the dissipation of the mitochondrial membrane potential following Tetramethylrhodamine or 5,5,6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine chloride staining (JC-1). Assessment of PLX in-vivo was carried out using Balb/C mice (toxicity) and CD-1 nu/nu immunocompromised mice (efficacy). HPLC analysis enabled detection of some primary compounds present within our long pepper extract. RESULTS: Our results indicated that an ethanolic long pepper extract selectively induces caspase-independent apoptosis in cancer cells, without affecting non-cancerous cells, by targeting the mitochondria, leading to dissipation of the mitochondrial membrane potential and increase in ROS production. Release of the AIF and endonuclease G from isolated mitochondria confirms the mitochondria as a potential target of long pepper. The efficacy of PLX in in-vivo studies indicates that oral administration is able to halt the growth of colon cancer tumors in immunocompromised mice, with no associated toxicity. These results demonstrate the potentially safe and non-toxic alternative that is long pepper extract for cancer therapy.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Piper/química , Extractos Vegetales/farmacología , Animales , Western Blotting , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Técnicas para Inmunoenzimas , Técnicas In Vitro , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neoplasias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
J Pharm Pharm Sci ; 17(3): 294-301, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25224344

RESUMEN

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.


Asunto(s)
Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A/metabolismo , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Té/química , Camellia sinensis/química , Camellia sinensis/metabolismo , Inhibidores Enzimáticos del Citocromo P-450/química , Inhibidores Enzimáticos del Citocromo P-450/metabolismo , Medicina Tradicional China , Relación Estructura-Actividad , Té/metabolismo
14.
Phytochemistry ; 94: 238-42, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23810285

RESUMEN

From the leaves of Sarracenia purpurea, collected in Mistissini, Quebec, Canada, four goodyerosides and three phenolics and nine known compounds, were isolated. The structures of the compounds were determined by mass spectrometry, including HRMS, and by 1D and 2D NMR spectroscopy.


Asunto(s)
Extractos Vegetales/análisis , Extractos Vegetales/química , Hojas de la Planta/química , Sarraceniaceae/química , Furanos/análisis , Furanos/química , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Monosacáridos/análisis , Monosacáridos/química , Fenoles/análisis , Fenoles/química , Extractos Vegetales/aislamiento & purificación , Quebec
15.
Phytochemistry ; 92: 122-7, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23747054

RESUMEN

The widespread use of Neurolaena lobata (L.) R. Br. ex Cass. by Q'eqchi' Maya and indigenous healers throughout the Caribbean for inflammatory conditions prompted the study of the anti-inflammatory activity of this traditional medicine. The objectives of this study were to conduct a detailed ethnobotanical investigation of the uses of N. lobata by the Q'eqchi' Maya of Belize for a variety of inflammatory symptoms and to evaluate the in vitro anti-inflammatory activity of leaf extract and isolated sesquiterpene lactones. The crude 80% EtOH extract of N. lobata leaves administered at 100 µg/mL reduced LPS-stimulated TNF-α production in THP-1 monocytes by 72% relative to the stimulated vehicle control. Isolated sesquiterpene lactones, neurolenins B, C+D, lobatin B and 9α-hydroxy-8ß-isovalerianyloxy-calyculatolide were more active (IC50=0.17-2.32 µM) than the positive control parthenolide (IC50=4.79 µM). The results provide a pharmacological and phytochemical basis for the traditional use of this leaf for inflammatory conditions.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Asteraceae/química , Medicina Tradicional , Hojas de la Planta/química , Sesquiterpenos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Estructura Molecular , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/biosíntesis
16.
Can J Physiol Pharmacol ; 90(2): 167-74, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22320845

RESUMEN

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.


Asunto(s)
Productos Finales de Glicación Avanzada/metabolismo , Extracto de Semillas de Uva/farmacología , Hipoglucemiantes/farmacología , Fenoles/farmacología , Proantocianidinas/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Vitis , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Glicosilación , Extracto de Semillas de Uva/análisis , Extracto de Semillas de Uva/aislamiento & purificación , Hipoglucemiantes/análisis , Hipoglucemiantes/aislamiento & purificación , Modelos Lineales , Fenoles/análisis , Fenoles/aislamiento & purificación , Proantocianidinas/análisis , Proantocianidinas/aislamiento & purificación , Semillas , Espectrofotometría Ultravioleta , Vitis/química
17.
Annu Rev Entomol ; 57: 405-24, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21942843

RESUMEN

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.


Asunto(s)
Control de Insectos , Insectos , Aceites Volátiles , Animales , Ambiente , Aceites Volátiles/química , Aceites Volátiles/toxicidad , Plantas/química , Control Social Formal
18.
Can J Microbiol ; 57(9): 745-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21859295

RESUMEN

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.


Asunto(s)
Antibacterianos/farmacología , Productos Biológicos/farmacología , Fucus/metabolismo , Acné Vulgar , Antibacterianos/metabolismo , Bahías , Productos Biológicos/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Haemophilus influenzae/efectos de los fármacos , Haemophilus influenzae/crecimiento & desarrollo , Haemophilus influenzae/aislamiento & purificación , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/crecimiento & desarrollo , Klebsiella pneumoniae/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Propionibacterium acnes/efectos de los fármacos , Propionibacterium acnes/crecimiento & desarrollo , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/aislamiento & purificación , Quebec , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/crecimiento & desarrollo , Streptococcus pneumoniae/aislamiento & purificación
19.
J Pharm Pharm Sci ; 14(1): 1-16, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21501549

RESUMEN

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.


Asunto(s)
Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos/efectos adversos , Extractos Vegetales/efectos adversos , Vitaminas/efectos adversos , Adulto , Colecalciferol/efectos adversos , Colecalciferol/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Suplementos Dietéticos , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Extractos Vegetales/farmacología , Vitaminas/farmacología , beta Caroteno/efectos adversos , beta Caroteno/farmacología
20.
Phytother Res ; 25(2): 264-70, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20648677

RESUMEN

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.


Asunto(s)
Ansiolíticos/farmacología , Ansiedad/tratamiento farmacológico , Extractos Vegetales/farmacología , Triterpenos/farmacología , Animales , Conducta Exploratoria/efectos de los fármacos , Magnoliopsida/química , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Triterpenos Pentacíclicos , Ratas , Ratas Sprague-Dawley , Ácido Betulínico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...