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1.
Nutr Neurosci ; 22(8): 596-606, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29343201

RESUMO

There is a growing body of evidence from randomized controlled trials which indicates that consumption of berries has a positive effect upon the cognitive function of healthy adults. It has been recommended that studies combining cognitive and physiological measures be undertaken in order to strengthen the evidence base for the putative effects of flavonoid consumption on cognitive outcomes. This pilot study utilized a randomized, double-blind and placebo controlled crossover design to assess the influence of the acute administration of anthocyanin-rich blackcurrant juice, standardized at 500 mg of polyphenols, on mood and attention. Additionally, this trial used electroencephalography (EEG) to assess if any changes in cognitive performance are associated with changes in localized prefrontal cortex neuronal activity in nine healthy young adults. Outcomes from the pilot EEG data highlight an anxiolytic effect of the consumption of a single serve blackcurrant juice, as indexed by a suppression of α spectral power, and an increase in the slow wave δ and θ spectral powers. There was also an indication of greater alertness and lower fatigue, as indexed by an increase in ß power and suppression of α spectral power. Outcomes from the CogTrack™ system indicated a small acute increase in reaction times during the digit vigilance task.


Assuntos
Afeto/efeitos dos fármacos , Atenção/efeitos dos fármacos , Ondas Encefálicas/efeitos dos fármacos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Ribes , Adulto , Antocianinas/administração & dosagem , Ansiolíticos/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Projetos Piloto , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Polifenóis/administração & dosagem , Tempo de Reação , Adulto Jovem
2.
Phytother Res ; 32(6): 1064-1072, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29464849

RESUMO

The traditional practice of eating the flowers of Clitoria ternatea L. or drinking their infusion as herbal tea in some of the Asian countries is believed to promote a younger skin complexion and defend against skin aging. This study was conducted to investigate the protective effect of C. ternatea flower water extract (CTW) against hydrogen peroxide-induced cytotoxicity and ultraviolet (UV)-induced mitochondrial DNA (mtDNA) damage in human keratinocytes. The protective effect against hydrogen peroxide-induced cytotoxicity was determined by 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay, and mtDNA damage induced by UV was determined by polymerase chain reaction. Preincubation of HaCaT with 100, 250, and 500 µg/ml CTW reduced cytotoxicity effects of H2 O2 compared with control (H2 O2 alone). CTW also significantly reduced mtDNA damage in UV-exposed HaCaT (p < .05). CTW was chemically-characterized using high resolution liquid chromatography-mass spectrometry. The main compounds detected were assigned as anthocyanins derived from delphinidin, including polyacylated ternatins, and flavonol glycosides derived from quercetin and kaempferol. These results demonstrated the protective effects of C. ternatea flower extracts that contain polyacylated anthocyanins and flavonol glycosides as major constituents, against H2 O2 and UV-induced oxidative stress on skin cells, and may provide some explanation for the putative traditional and cosmetic uses of C. ternatea flower against skin aging.


Assuntos
Antioxidantes/uso terapêutico , Clitoria/química , DNA Mitocondrial/efeitos adversos , Peróxido de Hidrogênio/metabolismo , Queratinócitos/efeitos dos fármacos , Extratos Vegetais/química , Antioxidantes/farmacologia , Humanos , Peróxido de Hidrogênio/análise
3.
Eur J Nutr ; 56(8): 2633, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28986604

RESUMO

In the original publication of the article, on page 7, paragraph "Discussion", line 12, 'blackcurrant has been observed to increase digit vigilance reaction time' should read as 'blackcurrant has been observed to decrease digit vigilance reaction time'.

4.
Eur J Nutr ; 56(8): 2621-2631, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28429081

RESUMO

PURPOSE: Berry-derived phenolic compounds found in grapes have been associated with a number of health benefits, including the augmentation of human brain function and cognition. Previous intervention studies of Concord grape juice have demonstrated improvement to memory and driving ability following 3- to 4-month supplementation in middle-aged and older adults. However, no studies to date have demonstrated acute cognitive benefits of grape juice, and investigation of these effects in young adults is lacking. METHODS: This randomised, placebo-controlled, double-blind, counterbalanced-crossover study, assessed the effects of 230 ml purple grape juice or sugar-matched control in 20 healthy young adults. Computerised measures of episodic memory, working memory, attention and mood were completed at baseline and following a 20-min absorption period. RESULTS: Purple grape juice significantly improved reaction time on a composite attention measure (p = 0.047) and increased calm ratings (p = 0.046) when compared to placebo. Order effects also indicated an enduring positive effect on pre-dose memory reaction time (p = 0.018) and post-dose calm ratings (p = 0.019) when purple grape was consumed first. CONCLUSIONS: These findings in a small sample of healthy young adults suggest that purple grape juice can acutely enhance aspects of cognition and mood. No significant effects of juice were observed on memory measures, suggesting that these may be less susceptible to manipulation following acute supplementation in healthy young adults. Potential mechanisms underlying these effects include modulation of cerebral blood flow, glucoregulation and inhibition of monoamine oxidase activity, all of which require further exploration.


Assuntos
Afeto , Cognição , Sucos de Frutas e Vegetais , Vitis/química , Adolescente , Adulto , Antocianinas/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Feminino , Flavonoides/administração & dosagem , Frutas/química , Humanos , Masculino , Memória , Fenóis/administração & dosagem , Compostos Fitoquímicos/administração & dosagem , Adulto Jovem
5.
Phytother Res ; 28(12): 1789-95, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25091506

RESUMO

Current conventional treatments for Parkinson's disease (PD) are aimed at symptom management, as there is currently no known cure or treatment that can slow down its progression. Ayurveda, the ancient medical system of India, uses a combination of herbs to combat the disease. Herbs commonly used for this purpose are Zandopa (containing Mucuna pruriens), Withania somnifera, Centella asiatica, Sida cordifolia and Bacopa monnieri. In this study, these herbs were tested for their potential ability to improve climbing ability of a fruit fly (Drosophila melanogaster) PD model based on loss of function of phosphatase and tensin-induced putative kinase 1 (PINK1). Fruit flies were cultured on food containing individual herbs or herbal formulations, a combination of all five herbs, levodopa (positive control) or no treatment (negative control). Tests were performed in both PINK1 mutant flies and healthy wild-type (WT) flies. A significant improvement in climbing ability was observed in flies treated with B. monnieri compared with untreated PINK1 mutant flies. However, a significant decrease in climbing ability was observed in WT flies for the same herb. Centella asiatica also significantly decreased climbing ability in WT flies. No significant effects were observed with any of the other herbs in either PINK1 or WT flies compared with untreated flies.


Assuntos
Drosophila melanogaster/efeitos dos fármacos , Ayurveda , Atividade Motora/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Bacopa/química , Centella/química , Modelos Animais de Doenças , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Índia , Levodopa , Mucuna/química , Doença de Parkinson , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Withania/química
6.
Phytomedicine ; 18(8-9): 691-6, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21183323

RESUMO

There is mounting evidence that the deposition and aggregation of ß-amyloid peptides (Aß) in the brain play a significant role in the development and pathogenesis of Alzheimer's disease. There is further evidence that free radical species such as hydrogen peroxide (H(2)O(2)) mediate Aß induced toxicity. Previous studies have demonstrated that green tea polyphenols possess neuroprotective properties through their ability to ameliorate oxidative stress induced by free radical species. Green tea polyphenols have also been shown to enhance cognition in various animal models of induced cognitive impairment. Upon ingestion, green tea polyphenols are metabolised and undergo bio-transformation which affects their bioavailability and therefore efficacy. In this study, a green tea extract was subjected to a simulated gastrointestinal digestion and a 'colon-available' extract (CAGTE) prepared and assessed for its potential protective effects against H(2)O(2) and Aß((1-42)) induced cytotoxicity using differentiated PC12 cells (dPC12) as a model for neuronal cells. CAGTE represents green tea phytochemicals potentially available after upper gastrointestinal digestion. CAGTE which was depleted in flavan-3-ols, as shown by LC-MS analysis, protected dPC12 cells at concentration ranges of 0.3-10 µg/ml and 0.03-0.125 µg/ml for H(2)O(2) and Aß((1-42)), induced cytotoxicity, respectively. At high concentrations, CAGTE exhibited direct anti-proliferative effects, in line with the reputed anti-cancer properties of green tea polyphenols. These results demonstrate that potentially bioavailable green tea metabolites are able to ameliorate both H(2)O(2) and Aß((1-42)) induced cytotoxicity.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Camellia sinensis/química , Peróxido de Hidrogênio/toxicidade , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/toxicidade , Extratos Vegetais/farmacologia , Animais , Flavonoides/metabolismo , Flavonoides/farmacologia , Neurônios/metabolismo , Fármacos Neuroprotetores/metabolismo , Células PC12 , Fenóis/metabolismo , Fenóis/farmacologia , Extratos Vegetais/metabolismo , Polifenóis , Ratos
7.
Phytother Res ; 24(10): 1567-74, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20680931

RESUMO

Withania somnifera L. Dunal (Solanaceae), also known as 'ashwagandha' in Sanskrit and as 'Indian ginseng', is used widely in Ayurvedic medicine as a nerve tonic and memory enhancer, with antiaging, antistress, immunomodulatory and antioxidant properties. There is a paucity of data on the potential neuroprotective effects of W. somnifera root, as traditionally used, against H(2)O(2)- and Aß((1-42))-induced cytotoxicity which are current targets for novel approaches to treat dementia, especially dementia of the Alzheimer's type (AD). In this study, an aqueous extract prepared from the dried roots of W. somnifera was assessed for potential protective effects against H(2)O(2)- and Aß((1-42))-aggregated fibril cytotoxicity by an MTT assay using a differentiated rat pheochromocytoma PC12 cell line. The results suggest that pretreatments of differentiated PC12 cells with aqueous extracts of W. somnifera root significantly protect differentiated PC12 cells against both H(2)O(2)- and Aß((1-42))-induced cytotoxicity, in a concentration dependent manner. To investigate the compounds that could explain the observed effects, the W. somnifera extract was analysed by liquid chromatography-serial mass spectrometry and numerous withanolide derivatives, including withaferin A, were detected. These results demonstrate the neuroprotective properties of an aqueous extract of W. somnifera root and may provide some explanation for the putative ethnopharmacological uses of W. somnifera for cognitive and other neurodegenerative disorders that are associated with oxidative stress.


Assuntos
Peptídeos beta-Amiloides/efeitos adversos , Peróxido de Hidrogênio/efeitos adversos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos adversos , Extratos Vegetais/farmacologia , Withania/química , Animais , Sobrevivência Celular , Ayurveda , Células PC12 , Raízes de Plantas/química , Ratos , Vitanolídeos/farmacologia
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