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1.
BMC Complement Altern Med ; 19(1): 137, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31215420

RESUMO

BACKGROUND: The Cree of Eeyou Istchee (James Bay area of northern Quebec) suffer from a high rate of diabetes and its complications partly due to the introduction of the western lifestyle within their culture. As part of a search for alternative medicine based on traditional practice, this project evaluates the biological activity of Picea mariana (Mill.) Britton, Sterns & Poggenb. needle, bark, and cone, in preventing glucose toxicity to PC12-AC cells in vitro (a diabetic neurophathy model) and whether habitat and growth environment influence this activity. METHODS: Three different organs (needle, bark, and cone) of P. mariana were collected at different geographical locations and ecological conditions and their 80% ethanolic extracts were prepared. Extracts were then tested for their ability to protect PC12-AC cells from hyperglycaemic challenge at physiologically relevant concentrations of 0.25, 0.5, 1.0 and 2.0 µg/mL. Folin-Ciocalteu method was used to determine the total phenolic content of P. mariana extracts. RESULTS: All extracts were well-tolerated in vitro exhibiting LD50 of 25 µg/mL or higher. Extracts from all tested organs showed a cytoprotective concentration-dependent response. Furthermore, the cytoprotective activity was habitat- and growth environment-dependent with plants grown in bog or forest habitats in coastal or inland environments exhibiting different cytoprotective efficacies. These differences in activity correlated with total phenolic content but not with antioxidant activity. In addition, this paper provides the first complete Ultra-Performance Liquid Chromatography-quadrupole time-of-flight (UPLC-QTOF) mass spectrometry analysis of Picea mariana's bark, needles and cones. CONCLUSIONS: Together, these results provide further understanding of the cytoprotective activity of Canadian boreal forest plants identified by the Cree healers of Eeyou Istchee in a cell model of diabetic neuropathy. Their activity is relevant to diabetic peripheral neuropathic complications and shows that their properties can be optimized by harvesting in optimal growth environments.


Assuntos
Diabetes Mellitus/fisiopatologia , Glucose/toxicidade , Hipoglicemiantes/farmacologia , Picea/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Hipoglicemiantes/análise , Células PC12 , Extratos Vegetais/análise , Substâncias Protetoras/análise , Quebeque , Ratos
2.
Conserv Biol ; 30(6): 1277-1287, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27032080

RESUMO

Many argue that monitoring conducted exclusively by scientists is insufficient to address ongoing environmental challenges. One solution entails the use of mobile digital devices in participatory monitoring (PM) programs. But how digital data entry affects programs with varying levels of stakeholder participation, from nonscientists collecting field data to nonscientists administering every step of a monitoring program, remains unclear. We reviewed the successes, in terms of management interventions and sustainability, of 107 monitoring programs described in the literature (hereafter programs) and compared these with case studies from our PM experiences in Australia, Canada, Ethiopia, Ghana, Greenland, and Vietnam (hereafter cases). Our literature review showed that participatory programs were less likely to use digital devices, and 2 of our 3 more participatory cases were also slow to adopt digital data entry. Programs that were participatory and used digital devices were more likely to report management actions, which was consistent with cases in Ethiopia, Greenland, and Australia. Programs engaging volunteers were more frequently reported as ongoing, but those involving digital data entry were less often sustained when data collectors were volunteers. For the Vietnamese and Canadian cases, sustainability was undermined by a mismatch in stakeholder objectives. In the Ghanaian case, complex field protocols diminished monitoring sustainability. Innovative technologies attract interest, but the foundation of effective participatory adaptive monitoring depends more on collaboratively defined questions, objectives, conceptual models, and monitoring approaches. When this foundation is built through effective partnerships, digital data entry can enable the collection of more data of higher quality. Without this foundation, or when implemented ineffectively or unnecessarily, digital data entry can be an additional expense that distracts from core monitoring objectives and undermines project sustainability. The appropriate role of digital data entry in PM likely depends more on the context in which it is used and less on the technology itself.


Assuntos
Computadores , Conservação dos Recursos Naturais , Coleta de Dados , Monitoramento Ambiental , Austrália , Canadá , Etiópia , Gana , Humanos
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.
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
5.
J Pharm Pharm Sci ; 18(4): 562-77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26626249

RESUMO

PURPOSE: The purpose of this study was to assess safety of the traditional antidiabetic extracts of either S. purpurea or its lead active principle, morroniside at the transcriptional level. The overarching objective was to profile and validate transcriptional changes in the cytochrome P450 family of genes, in response to treatment with S. purpurea ethanolic extract or its lead active, morroniside. METHODS: Transcriptional activity was profiled using a 19K human cDNA microarray in C2BBe1 cells, clone of Caco-2 intestinal cells, which are a model of first-pass metabolism (1, 2). Cells were treated with S. purpurea extract for 4 and 24 hrs, as well as the pure compound morroniside for 4 hrs, to determine their effects. RESULTS: No evidence of cytochrome P450 transcriptome regulation or of transcriptional activation of other diabetes relevant mRNA was detected after rigorous quantitative-PCR validation of microarray results. CONCLUSION: Our data do not support a transcriptional mechanism of action for either S. purpurea extract or its lead active, morroniside. 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
Sistema Enzimático do Citocromo P-450/genética , Glicosídeos/toxicidade , Extratos Vegetais/toxicidade , Sarraceniaceae/química , Células CACO-2 , DNA Complementar/genética , Glicosídeos/isolamento & purificação , Humanos , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/toxicidade , Indígenas Norte-Americanos , Medicina Tradicional , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Extratos Vegetais/isolamento & purificação , Reação em Cadeia da Polimerase , Quebeque , RNA Mensageiro/metabolismo , Fatores de Tempo
6.
Planta Med ; 80(8-9): 732-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24963620

RESUMO

A method was developed to distinguish Vaccinium species based on leaf extracts using nuclear magnetic resonance spectroscopy. Reference spectra were measured on leaf extracts from several species, including lowbush blueberry (Vaccinium angustifolium), oval leaf huckleberry (Vaccinium ovalifolium), and cranberry (Vaccinium macrocarpon). Using principal component analysis, these leaf extracts were resolved in the scores plot. Analysis of variance statistical tests demonstrated that the three groups differ significantly on PC2, establishing that the three species can be distinguished by nuclear magnetic resonance. Soft independent modeling of class analogies models for each species also showed discrimination between species. To demonstrate the robustness of nuclear magnetic resonance spectroscopy for botanical identification, spectra of a sample of lowbush blueberry leaf extract were measured at five different sites, with different field strengths (600 versus 700 MHz), different probe types (cryogenic versus room temperature probes), different sample diameters (1.7 mm versus 5 mm), and different consoles (Avance I versus Avance III). Each laboratory independently demonstrated the linearity of their NMR measurements by acquiring a standard curve for chlorogenic acid (R(2) = 0.9782 to 0.9998). Spectra acquired on different spectrometers at different sites classifed into the expected group for the Vaccinium spp., confirming the utility of the method to distinguish Vaccinium species and demonstrating nuclear magnetic resonance fingerprinting for material validation of a natural health product.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Metabolômica , Extratos Vegetais/isolamento & purificação , Vaccinium/química , Ácido Clorogênico/normas , Extratos Vegetais/química , Folhas de Planta/química , Análise de Componente Principal , Padrões de Referência , Especificidade da Espécie , Vaccinium/classificação
7.
Plant Foods Hum Nutr ; 69(1): 71-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24448675

RESUMO

Evidence supports the health promoting benefits of berries, particularly with regard to the prevention and management of chronic diseases such cardio- and cerebrovascular disease, diabetes and Alzheimer's disease. Two related pathophysiological features common to many of these conditions are oxidative stress and the accumulation of advanced glycation endproducts (AGEs). Whereas antioxidant properties are well-established in several species of berries and are believed central to their protective mechanisms, few studies have investigated the effects of berries on AGE formation. Here, employing a series of complementary in vitro assays, we evaluated a collection of wild berry extracts for 1) inhibitory effects on fluorescent-AGE and Nε- (carboxymethyl)lysine-albumin adduct formation, 2) radical scavenging activity and 3) total phenolic and anthocyanin content. All samples reduced AGE formation in a concentration-dependent manner that correlated positively with each extract's total phenolic content and, to a lesser degree, total anthocyanin content. Inhibition of AGE formation was similarly related to radical scavenging activities. Adding antiglycation activity to the list of established functional properties ascribed to berries and their phenolic metabolites, our data provide further insight into the active compounds and protective mechanisms through which berry consumption may aid in the prevention and treatment of chronic diseases associated with AGE accumulation and toxicity. As widely available, safe and nutritious foods, berries represent a promising dietary intervention worthy of further investigation.


Assuntos
Antocianinas/farmacologia , Antioxidantes/farmacologia , Dieta , Frutas/química , Produtos Finais de Glicação Avançada/metabolismo , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/farmacologia , Alimento Funcional , Humanos , Plantas Comestíveis/química
8.
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
9.
Front Nutr ; 10: 1061611, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37252236

RESUMO

Introduction: In the French overseas department of French Guiana, in South America, nutrition therapy for the management of diabetes is based on French guidelines. However, this region is demographically diverse and includes several populations of Indigenous Peoples, Parikwene among others, also called Palikur. Due to socio-economical, cultural, and geographical differences, along with distinctions in the local food system, dietary recommendations, which many consider in the context of post-colonial power dynamics, are not well suited to local populations. In the absence of suitable recommendations, it is hypothesized that local populations will adapt their dietary practices considering diabetes as an emerging health problem. Methods: Seventy-five interviews were conducted with community members and Elders, as well as healthcare professionals and administrators providing services to the Parikwene population of Macouria and Saint-Georges de l'Oyapock communes. Data regarding the representation of cassava (Manihot esculenta Crantz) consumption and diabetes were collected via semi-structured interviews and participant observation (i.e., observation and participation in community activities), namely via participating in activities related to the transformation of cassava tubers at swidden and fallow fields. Results and Discussion: Parikwene have adapted the transformation of cassava tubers for their consumption in the management of diabetes.The importance of cassava tubers as a staple and core food to the Parikwene food system was established by identifying it as a cultural keystone species. Narratives illustrated conflicting perceptions regarding the implication of cassava consumption in the development of diabetes. Adaptations to the operational sequence involved in the transformation of cassava tubers led to the production of distinct cassava roasted semolina (i.e., couac), based on organoleptic properties (i.e., sweet, and acidic couac). Preferences for the consumption of acidic couac were grounded in the Parikwene knowledge system, as well as attention to diabetes related symptoms and glucometer readings. Conclusion: These results provide important insights related to knowledge, attitudes, and practices in developing locally and culturally adapted approaches to providing dietary recommendations in the treatment of diabetes.

10.
Plants (Basel) ; 13(1)2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38202347

RESUMO

Botanical surveys in all parts of Pakistan are mainly focused on ethnomedicinal uses of plants, and very little attention has been paid to documenting edible wild fruit species (EWFs). Multiple methodologies and tools were used for data collection. In a recent survey 74 EWF species belonging to 29 families were documented, including their medicinal uses for the treatment of various diseases. The most cited (23%) preparation method was raw, fresh parts. The UV and RFC of EWF species ranged from 0.08 to 0.4 and from 0.02 to 0.18, respectively. In terms of specific disease treatments and their consensus, the ICF ranged from 0 to 0.38. Sexual, gastrointestinal, and respiratory disorders had the highest use reports, and 11 species of plants had the highest FL of 100%. On the basis of uses reported by the inhabitants of seven districts of Southern Khyber Pakhtunkhwa Province, the CSI ranged from the lowest 1.3 to the highest 41. It is concluded that the traditional uses of EWF species depend mainly on socio-economic factors rather than climatic conditions or the number of species. However, there is a gradual loss of traditional knowledge among the younger generations. The present survey is the first baseline study about the socio-economic dimension of local communities regarding the use of EWF species for food as well as medicine.

11.
Artigo em Inglês | MEDLINE | ID: mdl-22235232

RESUMO

Canadian Aboriginals, like others globally, suffer from disproportionately high rates of diabetes. A comprehensive evidence-based approach was therefore developed to study potential antidiabetic medicinal plants stemming from Canadian Aboriginal Traditional Medicine to provide culturally adapted complementary and alternative treatment options. Key elements of pathophysiology of diabetes and of related contemporary drug therapy are presented to highlight relevant cellular and molecular targets for medicinal plants. Potential antidiabetic plants were identified using a novel ethnobotanical method based on a set of diabetes symptoms. The most promising species were screened for primary (glucose-lowering) and secondary (toxicity, drug interactions, complications) antidiabetic activity by using a comprehensive platform of in vitro cell-based and cell-free bioassays. The most active species were studied further for their mechanism of action and their active principles identified though bioassay-guided fractionation. Biological activity of key species was confirmed in animal models of diabetes. These in vitro and in vivo findings are the basis for evidence-based prioritization of antidiabetic plants. In parallel, plants were also prioritized by Cree Elders and healers according to their Traditional Medicine paradigm. This case study highlights the convergence of modern science and Traditional Medicine while providing a model that can be adapted to other Aboriginal realities worldwide.

12.
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
13.
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
14.
Planta Med ; 77(2): 196-204, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20717877

RESUMO

Nonenzymatic formation of advanced glycation end products (AGEs) is accelerated under hyperglycemic conditions characteristic of type 2 diabetes mellitus and contributes to the development of vascular complications. As such, inhibition of AGE formation represents a potential therapeutic target for the prevention and treatment of diabetic complications. In the present study, ethanolic extracts of 17 medicinal plants were assessed for inhibitory effects on in vitro AGE formation through fluorometric and immunochemical detection of fluorescent AGEs and N(ε)-(carboxymethyl)lysine adducts of albumin (CML-BSA), respectively. Most extracts inhibited fluorescent AGE formation with IC (50) values ranging from 0.4 to 38.6 µg/mL and all extracts reduced CML-BSA formation but to differing degrees. Results obtained through both methods were highly correlated. Antiglycation activities were positively correlated with total phenolic content, free radical scavenging activity and reduction in malonyldiadehyde levels following oxidation of low-density lipoprotein, but negatively correlated with lag time to formation of conjugated dienes. Together, these results provide evidence that antioxidant phenolic metabolites mediate the antiglycation activity of our medicinal plant collection, a relationship that likely extends to other medicinal and food plants.


Assuntos
Antioxidantes/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Canadá , Sequestradores de Radicais Livres/química , Produtos Finais de Glicação Avançada/química , Produtos Finais de Glicação Avançada/metabolismo , Lisina/análogos & derivados , Lisina/antagonistas & inibidores , Lisina/química , Malondialdeído/química , Oxirredução , Extratos Vegetais/química , Fatores de Tempo
15.
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.

16.
Phytother Res ; 24(5): 741-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19927274

RESUMO

Like many aboriginal populations, First Nations communities such as the Cree of Eeyou Istchee are facing continuously increasing rates of diabetes and related complications. Advanced glycation endproducts (AGEs), which readily form and accumulate with sustained hyperglycemia, contribute to the development of diabetic complications and, as such, are considered a potential therapeutic target. In the present study, the inhibition of AGE formation by ethanolic extracts of the Cree medicinal plant Vaccinium vitis-idaea L. was assessed by fluorometric detection of fluorescent AGEs and immunodetection of N(epsilon)-(carboxymethyl)lysine adducts of albumin. Extracts from V. vitis-idaea berries demonstrated a concentration-dependent inhibition of AGE formation in both measures. High performance liquid chromatography mass spectrometry (HPLC/MS) identified nine main phenolic constituents. Four were selected for further testing, of which catechin, quercetin-3-O-galactoside and cyanidin-3-O-glucoside but not para-coumaric acid displayed antiglycation activities. These results demonstrate that the flavonoid components of the berry extract are potent antiglycation agents and provide pharmacological validation for the traditional use of V. vitis-idaea as an antidiabetic remedy.


Assuntos
Flavonoides/química , Produtos Finais de Glicação Avançada/química , Fenóis/química , Extratos Vegetais/química , Vaccinium vitis-Idaea/química , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Frutas/química , Lisina/análogos & derivados , Medicina Tradicional , Fenóis/isolamento & purificação
17.
Phytochem Anal ; 21(4): 328-39, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20135709

RESUMO

INTRODUCTION: Ericaceae medicinal plants are traditionally used by the Eeyou Istchee Cree and other northern peoples of North America to treat type 2 diabetic symptoms. Because of the importance of phenolics as potential cures for degenerative diseases including type 2 diabetes, an analytical method was developed to detect them in the leaf extracts of 14 Ericaceae plants. OBJECTIVE: To develop an optimised method which is applicable to a relatively large number of Ericaceae plants using their leaf extracts. For this purpose phenolics with a wide range of polarity, including a glucosylated benzoquinone, two phenolic acids, three flavanols, a flavanone, a flavone and five flavonols, were included in this study. METHODOLOGY: Characterisation of phytochemicals in extracts was undertaken by automated matching to the UV spectra to those of an in house library of plant secondary metabolites and the authentication of their identity was achieved by reversed phase-high-performance chromatography-diode array detection-atmospheric pressure chemical ionisation/mass selective detection. RESULTS: Twenty-six phenolics were characterised within 26 min of chromatographic separation in 80% ethanol extracts of 14 Ericaceae plants. The calibration curves were linear within 0.5-880 microg/g dry mass of the plant with regression values better than 0.995. The limits of detection ranged from 0.3 for microg/mL for (+)-catechin to 2.6 microg/mL for chlorogenic acid. This is a first study dealing with relatively large number of Ericaceae extracts and is applicable to other plants of same family.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ericaceae/química , Indígenas Norte-Americanos , Plantas Medicinais/química , Humanos , Limite de Detecção
18.
Can J Physiol Pharmacol ; 87(6): 479-92, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19526043

RESUMO

Among the Cree of northern Quebec, the disproportionately high rate of diabetic complications is largely due to the cultural inadequacy of modern therapies for type 2 diabetes. To establish culturally adapted antidiabetic treatments, our team identified several candidate plant species used by the Cree to treat symptoms of diabetes. An initial study focused on 8 species and revealed that most possess significant in vitro antidiabetic activity. The purpose of the present study was to assess a further 9 species identified through the ethnobotanical survey. Crude plant extracts were screened for (i) potentiation of basal and insulin-stimulated glucose uptake by skeletal muscle cells (C2C12) and adipocytes (3T3-L1); (ii) potentiation of glucose-stimulated insulin secretion by pancreatic beta cells (betaTC); (iii) potentiation of adipogenesis in 3T3-L1 cells; (iv) protection against glucose toxicity and glucose deprivation in PC12-AC neuronal precursor cells; and (v) diphenylpicrylhydrazyl (DPPH) oxygen free radical scavenging. Four species potentiated basal glucose uptake in muscle cells or adipocytes, one species being as potent as metformin. Adipogenesis was accelerated by 4 species with a potency roughly half that of rosiglitazone. Five species protected PC12-AC cells against glucose toxicity and 4 protected against glucose deprivation. Five species exhibited antioxidant activity comparable to ascorbic acid. However, no species increased insulin secretion. The present study revealed that Gaultheria hispidula, Rhododendron tomentosum, and Vaccinium vitis-idaea exhibit a promising profile of antidiabetic potential and are good candidates for more in-depth evaluation.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Indígenas Norte-Americanos , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Árvores , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Diabetes Mellitus Tipo 2/etnologia , Relação Dose-Resposta a Droga , Radicais Livres/metabolismo , Glucose/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Camundongos , Células PC12 , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacologia , Plantas Medicinais/classificação , Quebeque/epidemiologia , Ratos
19.
Biomed Chromatogr ; 23(8): 865-72, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19353716

RESUMO

An HPLC method permitting the simultaneous determination of fourteen analytes (phenylalkanoids and monoterpenoids) from the roots of Rhodiola rosea was developed. A separation was achieved within 35 min using C(18) column material and a water-acetonitrile mobile phase, both containing a 0.05% phosphoric acid gradient system and a temperature of 53 degrees C. The method was validated for linearity, repeatability, limits of detection and limits of quantification. The limits of detection and limits of quantification of 14 phenylalkanoids and monoterpenoids were found to be 0.20-1.0 and 0.5-3.5 microg/mL, respectively. The wavelengths used for quantification of phenylalkanoids and monoterpenoids with a diode array detector were 205, 220 and 251 nm. The method was used to analyze the roots of two species of Rhodiola and commercial extracts of R. rosea and provides preliminary evidence of phytochemical differences between North American and Eurasian populations of R. rosea. LC-mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification of phenylalkanoids and monoterpenoids in various Rhodiola samples. This method involved the use of the [M + H](+), [M + NH(4)](+) and [M + Na](+) ions in the positive ion mode with extractive ion monitoring (EIM).


Assuntos
Derivados de Benzeno/análise , Cromatografia Líquida de Alta Pressão/métodos , Dissacarídeos/análise , Monoterpenos/análise , Raízes de Plantas/química , Rhodiola/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Derivados de Benzeno/isolamento & purificação , Dissacarídeos/isolamento & purificação , Modelos Lineares , Monoterpenos/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
J Ethnopharmacol ; 194: 651-657, 2016 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-27773798

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Larix laricina, a native tree of North America, is a highly respected medicinal plant used for generations by Indigenous Peoples across its range, including the Cree of northern Québec who use the bark to treat symptoms of diabetes. This study investigates the antioxidant capacity and bioavailability of active constituents identified in L. laricina bark extracts. MATERIALS AND METHODS: (1) Oxygen radical absorbance capacity (ORAC) assay was employed to test antioxidant capacity of organic extracts (80% ethanol) from bark of L. laricina as well as fractions, isolated compounds, and media samples collected during permeability assays. (2) Caco-2 cell monolayer cultures were used to determine the permeability of identified antioxidants, which were quantified in basolateral media samples using liquid chromatography - tandem mass spectrometry (HPLC-ESI-MS/MS). RESULTS: Crude ethanolic extract possessed strong antioxidant potential in vitro (7.1±0.3 Trolox equivalents (TE) µM/mg). Among the 16 L. laricina fractions obtained by chromatographic separation, fraction 10 (F10) showed the highest antioxidant capacity (21.8±1.7µm TE/mg). Among other identified antioxidants, the stilbene rhaponticin (isolated from F10) was the most potent (24.6±1.1µm TE/mg). Caco-2 transport studies revealed that none of the identified compounds were detectable in basolateral samples after 2-h treatment with crude extract. In monolayers treated with F10 (60% rhaponticin), small quantities of rhaponticin were increasingly detected over time in basolateral samples with an apparent permeability coefficient (Papp) of 1.86×10-8cm/s (0-60min). To model potential effects on blood redox status, we evaluated the antioxidant capacity of collected basolateral samples and observed enhanced activity over time after exposure to both extract and F10 (75µg/mL) relative to control. CONCLUSIONS: By profiling the antioxidant constituents of L. laricina bark, we identified rhaponticin as the most potent oxygen radical scavenger and observed low permeability in Caco-2 cell monolayers but an increase in basolateral antioxidant capacity.


Assuntos
Larix/química , Medicina Tradicional , Casca de Planta/química , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Humanos , Indígenas Norte-Americanos , Espectrometria de Massas por Ionização por Electrospray
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