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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.
BMC Complement Altern Med ; 18(1): 37, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29378549

RESUMO

BACKGROUND: Our team has identified 17 Boreal forest species from the traditional pharmacopeia of the Eastern James Bay Cree that presented promising in vitro and in vivo biological activities in the context of type 2 diabetes (T2D). We now screened the 17 plants extracts for potential anti-apoptotic activity in cultured kidney cells and investigated the underlying mechanisms. METHODS: MDCK (Madin-Darnby Canine Kidney) cell damage was induced by hypertonic medium (700 mOsm/L) in the presence or absence of maximal nontoxic concentrations of each of the 17 plant extracts. After 18 h' treatment, cells were stained with Annexin V (AnnV) and Propidium iodide (PI) and subjected to flow cytometry to assess the cytoprotective (AnnV-/PI-) and anti-apoptotic (AnnV+/PI-) potential of the 17 plant extracts. We then selected a representative subset of species (most cytoprotective, moderately so or neutral) to measure the activity of caspases 3, 8 and 9. RESULTS: Gaultheria hispidula and Abies balsamea are amongst the most powerful cytoprotective and anti-apoptotic plants and appear to exert their modulatory effect primarily by inhibiting caspase 9 in the mitochondrial apoptotic signaling pathway. CONCLUSION: We conclude that several Cree antidiabetic plants exert anti-apoptotic activity that may be relevant in the context of diabetic nephropathy (DN) that affects a significant proportion of Cree diabetics.


Assuntos
Hipoglicemiantes/farmacologia , Medicina Tradicional , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Substâncias Protetoras/farmacologia , Animais , Anexina A5/química , Apoptose/efeitos dos fármacos , Canadá , Caspases/metabolismo , Nefropatias Diabéticas/metabolismo , Cães , Hipoglicemiantes/química , Células Madin Darby de Rim Canino , Extratos Vegetais/química , Propídio/química , Substâncias Protetoras/química
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.
Phytother Res ; 30(3): 439-46, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26666462

RESUMO

Bioassay-guided fractionation of the crude extract (80% EtOH) of the leaves of Cestrum schlechtendahlii, a plant used by Q'eqchi' Maya healers for treatment of athlete's foot, resulted in the isolation and identification of two spirostanol saponins (1 and 2). Structure elucidation by MS, 1D-NMR, and 2D-NMR spectroscopic methods identified them to be the known saponin (25R)-1ß,2α-dihydroxy-5α-spirostan-3-ß-yl-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-galactopyranoside (1) and new saponin (25R)-1ß,2α-dihydroxy-5α-spirostan-3-ß-yl-O-ß-D-galactopyranoside (2). While 2 showed little or no antifungal activity at the highest concentration tested, 1 inhibited growth of Saccharomyces cerevisiae (minimum inhibitory concentration (MIC) of 15-25 µM), Candida albicans, Cryptococcus neoformans, and Fusarium graminearum (MIC of 132-198 µM).


Assuntos
Antifúngicos/farmacologia , Cestrum/química , Fungos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Espirostanos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Etnicidade , Fusarium/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fitoterapia , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais , Saccharomyces cerevisiae/efeitos dos fármacos , Saponinas/química , Saponinas/isolamento & purificação , Solanaceae , Espirostanos/química , Espirostanos/isolamento & purificação
5.
J Pharm Pharm Sci ; 18(4): 729-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26626256

RESUMO

PURPOSE: Natural products have been a great source of medications used in conventional medicines for the treatment of various diseases; more importantly, they have played a significant role in the development of anti-cancer drugs for a number of decades. The benefits to employing whole extracts of natural health products, rather than a single ingredient, for cancer treatment remains unexplored. Our research group has previously demonstrated the potential anti-cancer benefits of several natural health products (NHPs), prompting further studies into other NHPs, such as Neem (Azadarichta indica), a tree native to India and has been used in Ayurvedic medicine for over 4000 years. The objective of this study is to determine the possible anti-cancer potential of aqueous and ethanolic Neem leaf extracts (NLEs) and to identify the specific mode(s) of action. METHODS: Cells were treated with NLE and cell viability was then assessed using a water-soluble tetrazolium salt. Cell death was confirmed using the fluorescent dye propidium iodide and apoptosis was identified using the Annexin-V binding assay. Mitochondrial membrane permeabilization was visualized using JC-1 staining and the production of whole cell and mitochondrial ROS was measured with 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) and Amplex Red, respectively. In vivo efficacy of aqueous NLE was assessed in human tumour xenografts in CD-1 nu/nu immunocompromised mice. RESULTS: Results indicate that both ethanolic and aqueous extracts of Neem leaf were effective in inducing apoptosis in leukemia and colon cancer cells, following destabilization of the mitochondrial membrane. Furthermore, an increase in the production of reactive oxygen species (ROS) was observed in cancer cells treated with NLEs, indicating that oxidative stress may play a role in the mechanism of cell death. Additionally, in vivo results showed that aqueous NLE (delivered orally) was well tolerated and inhibited tumour growth of human xenografts in mice. CONCLUSIONS: These findings suggest the potential of NLEs as safer and effective alternatives to conventional chemotherapy. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Meliaceae/química , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Humanos , Leucemia/tratamento farmacológico , Leucemia/patologia , Ayurveda , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/toxicidade , Folhas de Planta , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Pharm Pharm Sci ; 18(4): 484-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26626246

RESUMO

PURPOSE: The Cree of Eeyou Istchee in Northern Quebec identified Sarracenia purpurea L. as an important plant for the treatment of Type 2 diabetes. Traditionally the plant is used as a decoction (boiling water extract) of the leaf, however, in order to study the extract in a laboratory setting, an 80% ethanol extract was used. In this study, the phytochemistry of both extracts of the leaves was compared and quantified. METHODS: Two S. purpurea leaf extracts were prepared, one a traditional hot water extract and the other an 80% ethanol extract. Using UPLC-ESI-MS, the extracts were phytochemically compared for 2 triterpenes, betulinic acid and ursolic acid, using one gradient method and for 10 additional substances, including the actives quercetin-3-O-galactoside and morroniside, using a different method. RESULTS: The concentrations of the nine phenolic substances present, as well as an active principle, the iridoid glycoside morroniside, were very similar between the two extracts, with generally slightly higher concentrations of phenolics in the ethanol extract as expected. However, two triterpenes, betulinic acid and ursolic acid, were 107 and 93 times more concentrated, respectively, in the ethanol extract compared to the water extract. CONCLUSION: The main phytochemical markers and most importantly the antidiabetic active principles, quercetin-3-O-galactoside and morroniside, were present in similar amounts in the two extracts, which predicts similar bioactivity.This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Sarraceniaceae/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Etanol/química , Humanos , Hipoglicemiantes/química , Hipoglicemiantes/isolamento & purificação , Indígenas Norte-Americanos , Medicina Tradicional , Folhas de Planta , Quebeque , Espectrometria de Massas por Ionização por Electrospray/métodos , Água/química
7.
Arch Insect Biochem Physiol ; 87(4): 234-49, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25270601

RESUMO

Insecticide synergists biochemically inhibit insect metabolic enzyme activity and are used both to increase the effectiveness of insecticides and as a diagnostic tool for resistance mechanisms. Considerable attention has been focused on identifying new synergists from phytochemicals with recognized biological activities, specifically enzyme inhibition. Jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana (Mill.) BSP.), balsam fir (Abies balsamea (L.) Mill.), and tamarack larch (Larix laricina (Du Roi) Koch) have been used by native Canadians as traditional medicine, specifically for the anti-inflammatory and antioxidant properties based on enzyme inhibitory activity. To identify the potential allelochemicals with synergistic activity, ethanol crude extracts and methanol/water fractions were separated by Sephadex LH-20 chromatographic column and tested for in vitro glutathione S-transferase (GST) inhibition activity using insecticide-resistant Colorado potato beetle, Leptinotarsa decemlineata (Say) midgut and fat-body homogenate. The fractions showing similar activity were combined and analyzed by ultra pressure liquid chromatography-mass spectrometry. A lignan, (+)-lariciresinol 9'-p-coumarate, was identified from P. mariana cone extracts, and L. laricina and A. balsamea bark extracts. A flavonoid, taxifolin, was identified from P. mariana and P. banksiana cone extracts and L. laricina bark extracts. Both compounds inhibit GST activity with taxifolin showing greater activity compared to (+)-lariciresinol 9'-p-coumarate and the standard GST inhibitor, diethyl maleate. The results suggested that these compounds can be considered as potential new insecticide synergists.


Assuntos
Besouros/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glutationa Transferase/antagonistas & inibidores , Sinergistas de Praguicidas , Extratos Vegetais/farmacologia , Traqueófitas/química , Animais , Besouros/enzimologia , Inibidores Enzimáticos/química , Corpo Adiposo/efeitos dos fármacos , Corpo Adiposo/enzimologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Glutationa Transferase/metabolismo , Resistência a Inseticidas , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Lignanas/farmacologia , Extratos Vegetais/química , Quercetina/análogos & derivados , Quercetina/farmacologia
8.
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
9.
Planta Med ; 79(15): 1385-91, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23975866

RESUMO

Rhodiola rosea is a medicinal plant used by the indigenous Inuit people of Nunavik and Nunatsiavut, Eastern Canada, as a mental and physical rejuvenating agent. This traditional use led to the present investigation of R. rosea in the context of anxiety disorders. An alcohol extract of R. rosea roots was characterized phytochemically and orally administered for three consecutive days to Sprague-Dawley rats at 8 mg/kg, 25 mg/kg, and 75 mg/kg body weight. The rats were subjected to three behavioral paradigms of anxiety, including the elevated plus maze, social interaction, and contextual conditioned emotional response tests. Rhodiola rosea showed dose-dependent anxiolytic activity in the elevated plus maze and conditioned emotional response tests, with moderate effects in the higher-anxiety SI test. The active dose varied according to the anxiety test. In order to elucidate a mechanism, the extract was further tested in an in vitro GABAA-benzodiazepine receptor-binding assay, where it demonstrated low activity. This study provides the first comparative assessment of the anxiolytic activity of Nunavik R. rosea in several behaviour models and suggests that anxiolytic effects may be primarily mediated via pathways other than the GABAA-benzodiazepine site of the GABAA receptor.


Assuntos
Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Rhodiola , Administração Oral , Animais , Ansiolíticos/farmacologia , Ansiedade/metabolismo , Comportamento Animal/efeitos dos fármacos , Canadá , Proteínas de Transporte/metabolismo , Relação Dose-Resposta a Droga , Humanos , Indígenas Norte-Americanos , Masculino , Aprendizagem em Labirinto , Medicina Tradicional , Extratos Vegetais/farmacologia , Raízes de Plantas , Plantas Medicinais , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/metabolismo
10.
Transgenic Res ; 21(4): 757-71, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22083247

RESUMO

Detection and quantification of the levels of adventitious presence of genetically modified (GM) soybeans in non-GM grain shipments currently requires sophisticated tests that can have issues with their reproducibility. We show here that pigment biosynthesis in the soybean seed coat can be manipulated to provide a distinct color that would enable the simple visible detection of the GM soybean grain. We observed that a distinct red-brown grain color could be engineered by the simultaneous suppression of two proanthocyanidin (PA) genes, ANTHOCYANIDIN REDUCTASE1 (ANR1) and ANR2. Multiple reaction monitoring by liquid chromatography tandem mass spectrometry was used to quantify differentially accumulated seed coat metabolites, and revealed the redirection of metabolic flux into the anthocyanin pigment pathway and unexpectedly the flavonol-3-O-glucoside pathway. The upregulations of anthocyanin isogenes (DFR1 and GST26) and the anthocyanin/flavonol-3-O-glycosyltransferase (UGT78K2) were identified by quantitative RT-PCR to be endogenous feedback and feedforward responses to overaccumulation of upstream flavonoid intermediates resulting from ANR1 and ANR2 suppressions. These results suggested the transcription of flavonoid genes to be a key component of the mechanism responsible for the redirection of metabolite flux. This report identifies the suppression of PA genes to be a novel approach for engineering pigmentation in soybean grains.


Assuntos
Antocianinas/genética , Glycine max/genética , Pigmentos Biológicos , Plantas Geneticamente Modificadas , Cor , Regulação da Expressão Gênica de Plantas , Fenótipo , Pigmentação , Pigmentos Biológicos/biossíntese , Pigmentos Biológicos/genética , Proantocianidinas/genética , Proantocianidinas/metabolismo , Interferência de RNA , Sementes/genética , Sementes/metabolismo , Proteínas de Soja/genética
11.
J Nat Prod ; 75(7): 1284-8, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22738356

RESUMO

Through ethnobotanical surveys, the CIHR Team in Aboriginal Antidiabetic Medicines identified 17 boreal forest plants stemming from the pharmacopeia of the Cree First Nations of Eeyou Istchee (James Bay region of Northern Quebec) that were used traditionally against diabetes symptoms. The leaves of Sarracenia purpurea (pitcher plant), one of the identified Cree plants, exhibited marked antidiabetic activity in vitro by stimulating glucose uptake in C2C12 mouse muscle cells and by reducing glucose production in H4IIE rat liver cells. Fractionation guided by glucose uptake in C2C12 cells resulted in the isolation of 11 compounds from this plant extract, including a new phenolic glycoside, flavonoid glycosides, and iridoids. Compounds 6 (isorhamnetin-3-O-glucoside), 8 [kaempferol-3-O-(6″-caffeoylglucoside], and 11 (quercetin-3-O-galactoside) potentiated glucose uptake in vitro, which suggests they represent active principles of S. purpurea (EC(50) values of 18.5, 13.8, and 60.5 µM, respectively). This is the first report of potentiation of glucose uptake by compounds 6 and 8, while compound 11 (isolated from Vaccinium vitis) was previously shown to enhance glucose uptake. Treatment of H4IIE liver cells with the new compound 1, 6'-O-caffeoylgoodyeroside, decreased hepatic glucose production by reducing glucose-6-phosphatase enzymatic activity (IC(50) = 13.6 µM), which would contribute to lowering glycemia and to the antidiabetic potential of S. purpurea.


Assuntos
Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glucose-6-Fosfatase/metabolismo , Glucose/metabolismo , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Sarraceniaceae/química , Animais , Flavonoides/química , Glicosídeos/química , Humanos , Hipoglicemiantes/química , Indígenas Norte-Americanos , Medicina Tradicional , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Ratos
12.
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
13.
Artigo em Inglês | MEDLINE | ID: mdl-22888363

RESUMO

Larix laricina K. Koch is a medicinal plant belonging to traditional pharmacopoeia of the Cree of Eeyou Istchee (Eastern James Bay area of Canada). In vitro screening studies revealed that, like metformin and rosiglitazone, it increases glucose uptake and adipogenesis, activates AMPK, and uncouples mitochondrial function. The objective of this study was to evaluate the antidiabetic and antiobesity potential of L. laricina in diet-induced obese (DIO) C57BL/6 mice. Mice were subjected for eight or sixteen weeks to a high fat diet (HFD) or HFD to which L. laricina was incorporated at 125 and 250 mg/kg either at onset (prevention study) or in the last 8 of the 16 weeks of administration of the HFD (treatment study). L. laricina effectively decreased glycemia levels, improved insulin resistance, and slightly decreased abdominal fat pad and body weights. This occurred in conjunction with increased energy expenditure as demonstrated by elevated skin temperature in the prevention study and improved mitochondrial function and ATP synthesis in the treatment protocol. L. laricina is thus a promising alternative and complementary therapeutic approach for the treatment and care of obesity and diabetes among the Cree.

14.
BMC Complement Altern Med ; 12: 245, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-23216659

RESUMO

BACKGROUND: The purple pitcher plant, Sarracenia purpurea L., is a widely distributed species in North America with a history of use as both a marketed pain therapy and a traditional medicine in many aboriginal communities. Among the Cree of Eeyou Istchee in northern Québec, the plant is employed to treat symptoms of diabetes and the leaf extract demonstrates multiple anti-diabetic activities including cytoprotection in an in vitro model of diabetic neuropathy. The current study aimed to further investigate this activity by identifying the plant parts and secondary metabolites that contribute to these cytoprotective effects. METHODS: Ethanolic extracts of S. purpurea leaves and roots were separately administered to PC12 cells exposed to glucose toxicity with subsequent assessment by two cell viability assays. Assay-guided fractionation of the active extract and fractions was then conducted to identify active principles. Using high pressure liquid chromatography together with mass spectrometry, the presence of identified actives in both leaf and root extracts were determined. RESULTS: The leaf extract, but not that of the root, prevented glucose-mediated cell loss in a concentration-dependent manner. Several fractions elicited protective effects, indicative of multiple active metabolites, and, following subfractionation of the polar fraction, hyperoside (quercetin-3-O-galactoside) and morroniside were isolated as active constituents. Phytochemical analysis confirmed the presence of hyperoside in the leaf but not root extract and, although morroniside was detected in both organs, its concentration was seven times higher in the leaf. CONCLUSION: Our results not only support further study into the therapeutic potential and safety of S. purpurea as an alternative and complementary treatment for diabetic complications associated with glucose toxicity but also identify active principles that can be used for purposes of standardization and quality control.


Assuntos
Citoproteção/efeitos dos fármacos , Glucose/toxicidade , Extratos Vegetais/química , Plantas Medicinais/química , Substâncias Protetoras/química , Sarraceniaceae/química , Animais , Células PC12 , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Ratos
15.
J AOAC Int ; 95(5): 1406-11, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23175973

RESUMO

A single-laboratory-validated NMR spectroscopy method was established for determining the quantity of chlorogenic acid and hyperoside from crude extract material of blueberry leaves of the species Vaccinium angustifolium var. laevifolium House. The calibration curve of chlorogenic acid showed a highly linear regression, R = 0.99998. NMR spectroscopy identification and quantification of the constituents directly from the mixture, within the error of HPLC-diode array detector analysis, were determined as 7.53 mM chlorogenic acid (64.0 mg chlorogenic acid/g powdered leaf) and 0.77 mM hyperoside (8.58 mg hyperoside/g powdered leaf). The LOD was calculated to be 0.01 mM and the LOQ 0.01 mM by the 9 min and 13 s NMR spectroscopy experiment utilized. The assay showed no significant interference from different field strengths, extraction mesh size, gravimetric scale precision, NMR spectroscopy tube type, pulse program, amount of starting dry material, or day-to-day operation. The robustness of NMR spectroscopy as a means of definitively monitoring chlorogenic acid and hyperoside content directly from crude extracts was demonstrated by Youden statistical analysis.


Assuntos
Ácido Clorogênico/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/análogos & derivados , Vaccinium/química , Estrutura Molecular , Quercetina/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
BMC Genomics ; 12: 381, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21801362

RESUMO

BACKGROUND: The R locus controls the color of pigmented soybean (Glycine max) seeds. However information about its control over seed coat biochemistry and gene expressions remains limited. The seed coats of nearly-isogenic black (iRT) and brown (irT) soybean (Glycine max) were known to differ by the presence or absence of anthocyanins, respectively, with genes for only a single enzyme (anthocyanidin synthase) found to be differentially expressed between isolines. We recently identified and characterized a UDP-glycose:flavonoid-3-O-glycosyltransferase (UGT78K1) from the seed coat of black (iRT) soybean with the aim to engineer seed coat color by suppression of an anthocyanin-specific gene. However, it remained to be investigated whether UGT78K1 was overexpressed with anthocyanin biosynthesis in the black (iRT) seed coat compared to the nearly-isogenic brown (irT) tissue.In this study, we performed a combined analysis of transcriptome and metabolite data to elucidate the control of the R locus over seed coat biochemistry and to identify pigment biosynthesis genes. Two differentially expressed late-stage anthocyanin biosynthesis isogenes were further characterized, as they may serve as useful targets for the manipulation of soybean grain color while minimizing the potential for unintended effects on the plant system. RESULTS: Metabolite composition differences were found to not be limited to anthocyanins, with specific proanthocyanidins, isoflavones, and phenylpropanoids present exclusively in the black (iRT) or the brown (irT) seed coat. A global analysis of gene expressions identified UGT78K1 and 19 other anthocyanin, (iso)flavonoid, and phenylpropanoid isogenes to be differentially expressed between isolines. A combined analysis of metabolite and gene expression data enabled the assignment of putative functions to biosynthesis and transport isogenes. The recombinant enzymes of two genes were validated to catalyze late-stage steps in anthocyanin biosynthesis in vitro and expression profiles of the corresponding genes were shown to parallel anthocyanin biosynthesis during black (iRT) seed coat development. CONCLUSION: Metabolite composition and gene expression differences between black (iRT) and brown (irT) seed coats are far more extensive than previously thought. Putative anthocyanin, proanthocyanidin, (iso)flavonoid, and phenylpropanoid isogenes were differentially-expressed between black (iRT) and brown (irT) seed coats, and UGT78K2 and OMT5 were validated to code UDP-glycose:flavonoid-3-O-glycosyltransferase and anthocyanin 3'-O-methyltransferase proteins in vitro, respectively. Duplicate gene copies for several enzymes were overexpressed in the black (iRT) seed coat suggesting more than one isogene may have to be silenced to engineer seed coat color using RNA interference.


Assuntos
Perfilação da Expressão Gênica , Genes de Plantas/genética , Glycine max/genética , Glycine max/metabolismo , Pigmentação/genética , Sementes/genética , Sementes/metabolismo , Regulação para Baixo , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Pigmentos Biológicos/genética , Pigmentos Biológicos/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sementes/enzimologia , Glycine max/enzimologia , Regulação para Cima
17.
Planta Med ; 77(14): 1655-62, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21472650

RESUMO

Northern Labrador tea, Rhododendron tomentosum ssp. subarcticum, is one of the most commonly used medicinal plants by Inuit and other First Nations peoples of Canada. The phenolic profile and seasonal variation of this commonly used medicinal plant remains largely unknown. To assess optimal harvesting time, R. tomentosum was collected in accordance with traditional knowledge practices bimonthly throughout the snow-free summer in Iqaluit, Nunavut. The antioxidant potency was measured in a DPPH radical scavenging assay, and the anti-inflammatory activity was determined with a TNF-α production assay. The seasonal variation of phenolic content was assessed with HPLC-DAD for fifteen of the most abundant phenolic compounds; (+)-catechin, chlorogenic acid, PARA-coumaric acid, quercetin 3-O-galactoside (hyperoside), quercetin 3-O-glucoside (isoquercitrin), quercetin 3-O-rhamnoside (quercitrin), quercetin pentoside, myricetin, quercetin, 3 procyanidins, and 3 caffeic acid derivatives. The most abundant constituent was (+)-catechin, which made up 19 % of the total weight of characterized phenolics. There was significant seasonal variation in the quantity of all fifteen constituents assessed, whereas there was no seasonal variation of their total sum. The antioxidant activity was positively correlated with phenolic content and negatively correlated with daylight hours. The anti-inflammatory activity was negatively correlated with caffeic acid derivative 1 and daylight hours. Together these results demonstrate that the timing of harvest of R. tomentosum impacts the plant's phenolic content and its antioxidant and anti-inflammatory activities.


Assuntos
Anti-Inflamatórios/metabolismo , Antioxidantes/metabolismo , Fenóis/metabolismo , Extratos Vegetais/farmacologia , Rhododendron/metabolismo , Anti-Inflamatórios/análise , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/farmacologia , Canadá , Linhagem Celular Tumoral , Sequestradores de Radicais Livres/metabolismo , Humanos , Inuíte , Medicina Tradicional , Fenóis/análise , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Rhododendron/química , Estações do Ano , Fator de Necrose Tumoral alfa/metabolismo
18.
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
19.
Metabolites ; 11(8)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34436452

RESUMO

Several insect species use the amino acid proline as a major energy substrate. Although initially thought to be limited to blood-feeding dipterans, studies have revealed this capability is more widespread. Recent work with isolated flight muscle showed that the bumblebee Bombus impatiens can oxidize proline at a high rate. However, its role as a metabolic fuel to power flight is unclear. To elucidate the extent to which proline is oxidized to power flight and how its contribution changes during flight, we profiled 14 metabolites central to energy and proline metabolism at key time points in flight muscle and abdominal tissues. Ultra-high performance liquid chromatography-electrospray ionization-quadrupole time of flight mass spectrometry (UPLC-ESI-QTOF MS) analysis revealed that proline is likely used as a sparker metabolite of the tricarboxylic acid cycle at the onset of flight, whereby it supplements the intermediates of the cycle. Carbohydrates are the major energy substrates, which is evidenced by marked decreases in abdominal glycogen stores and a lack of alanine accumulation to replenish flight muscle proline. The time course of fuel stores and metabolites changes during flight highlights homeostatic regulation of energy substrates and patterns of changes in metabolic intermediates within pathways. This study clarifies the role of proline and carbohydrate metabolism during flight in hymenopterans, such as B. impatiens.

20.
Front Pharmacol ; 12: 511078, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35126097

RESUMO

An ethnopharmacological metanalysis was conducted with a large database available on antidiabetic activities of plant foods and medicines from the northern boreal forest, which are traditionally used by the indigenous Cree of James Bay, Quebec, Canada. The objective was to determine which bioassays are closely associated with the traditional knowledge of the Cree and which pharmacological metrics and phytochemical signals best define these plants and their groups. Data from 17 plant species, ethnobotanically ranked by syndromic importance value for treatment of 15 diabetic symptoms, was used along with 49 bioassay endpoints reported across numerous pharmacological studies and a metabolomics dataset. Standardized activities were separated into primary, secondary and safety categories and summed to produce a Pharmacological Importance Value (PIV) in each of the three categories for each species. To address the question of which pharmacological metrics and phytochemical signals best define the CEI anti-diabetes plants, multivariate analyses were undertaken to determine groupings of plant families and plant parts. The analysis identified Larix larcina as the highest PIV species in primary assays, Salix planifolia in secondary assays, and Kalmia angustifolia in safety assays, as well as a ranking of other less active species by PIV. Multivariate analysis showed that activity in safety PIV monitored mainly with cytochrome P450 inhibition patterns best reflected patterns of traditional medicine importance in Cree traditional knowledge, whereas potent primary bioactivities were seen in individual plants determined to be most important to the Cree for anti-diabetes purposes. In the secondary anti-diabetes assays, pharmacological variability was better described by plant biology, mostly in terms of the plant part used. Key signal in the metabolomics loadings plots for activity were phenolics especially quercetin derivatives. Traditional Indigenous knowledge in this analysis was shown to be able to guide the identification of plant pharmacological qualities in scientific terms.

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