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1.
Plants (Basel) ; 12(7)2023 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37050179

RESUMEN

Tomatoes (Solanum lycopersicum L.) of the variety Elpida were grown under standard Mediterranean greenhouse conditions during the spring season at three different nitrogen levels (low 6.4, standard 12.8, high 25.9 mM/plant), which were replicated during two consecutive years. Application of high nitrogen significantly increased the colour index a* (p < 0.001) but did not significantly affect yield or quality. The variety exhibited prolonged postharvest storage at room temperature (median survival time of 93 days). The maturation process was delayed by harvest at the breaker stage (2.5 days, p ≤ 0.001) or by super-optimal temperatures in the second year of experimentation (10 days, p ≤ 0.001). The colour indices L* and a* and the hue angle (a/b*) were positively correlated with the sum of total carotenoids, while differences in b* depended on the year of cultivation. The sustainability of this type of tomato production can be improved by reducing the nitrogen supply to less than the current standard practice, with minimal risk or negative effects on yield and quality of tomatoes.

2.
Nutrients ; 14(5)2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35268027

RESUMEN

Nitrate-rich food increases nitric oxide (NO) production and may have beneficial effects on vascular, metabolic, and brain function. This pilot study tested the effects of prolonged consumption of a range of doses of dietary nitrate (NO3-), provided as beetroot juice, on cognitive function and cerebral blood flow (CBF) in overweight and obese older participants. The study had a 13-week single-blind, randomised, parallel design, and 62 overweight and obese older participants (aged 60 to 75 years) received the following interventions: (1) high NO3- (2 × 70 mL beetroot juice/day) (2) medium NO3- (70 mL beetroot juice/day), (3) low NO3- (70 mL beetroot juice on alternate days), or (4) placebo (70 mL of NO3--depleted beetroot juice on alternate days). Cognitive functions were assessed using the Computerised Mental Performance Assessment System (COMPASS) assessment battery. CBF, monitored by concentration changes in oxygenated and deoxygenated haemoglobin, was assessed in the frontal cortex using near-infrared spectroscopy. The findings of this pilot study showed that cognitive function and CBF were not affected by supplementation with NO3--rich beetroot juice for 13 weeks, irrespective of the NO3- dose administered. These findings require confirmation in larger studies using more sophisticated imaging methods (i.e., MRI) to determine whether prolonged dietary NO3- supplementation influences brain function in older overweight people.


Asunto(s)
Beta vulgaris , Nitratos , Anciano , Beta vulgaris/química , Circulación Cerebrovascular , Cognición , Humanos , Persona de Mediana Edad , Obesidad/tratamiento farmacológico , Sobrepeso/tratamiento farmacológico , Proyectos Piloto , Método Simple Ciego
3.
Nutrients ; 13(3)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33653009

RESUMEN

Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO3-) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m2) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO3- (HN: 2 × 70 mL BJ/day) (2) medium-NO3- (MN: 70 mL BJ/day), (3) low-NO3- (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO3--depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO3- intake, and by measuring NO3- and NO2- concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO3- dose and the increase in plasma and urinary NO3- concentration (R2 = 0.71, P < 0.001 and R2 = 0.46 P < 0.001, respectively), but relationships between NO3- dose and changes in salivary NO3- and NO2- were non-linear (R2 = 0.35, P = 0.002 and R2 = 0.23, P = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults.


Asunto(s)
Beta vulgaris , Jugos de Frutas y Vegetales , Nitritos/administración & dosificación , Óxidos de Nitrógeno/metabolismo , Sobrepeso/metabolismo , Anciano , Suplementos Dietéticos , Ingestión de Alimentos/fisiología , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/metabolismo , Aceptación de la Atención de Salud/estadística & datos numéricos , Proyectos Piloto , Plasma/química , Saliva/química , Método Simple Ciego , Factores de Tiempo , Orina/química
4.
J Funct Foods ; 87: 104747, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34987615

RESUMEN

Two seaweeds; Ascophyllum nodosum and Fucus vesiculosus, were incorporated into bread at 0.5 and 2% and their effect on blood glucose in vivo and carbohydrate digestion in vitro were studied. In the five way randomised placebo controlled double blind pilot trial (n = 10) each volunteer consumed 100 g of available carbohydrate (from bread) and their blood glucose was measured over two hours. The breads were tested in a human digestion model and compared against control bread and control bread with the equivalent amount of seaweed. In the pilot human study the enriched breads did not cause any significant reductions in iAUC of blood glucose with average reductions of 0.1 ± 44.4%, 8.2 ± 19.3%, 1.0 ± 54.3% and 2.7 ± 31.9% for 0.5% F.vesiculosus, 0.5% A.nodosum, 2% F.vesiculosus, and 2% A.nodosum respectively. However, seaweed added alongside the control bread in vitro significantly reduced the level of carbohydrate digestion compared to the control bread. F.vesiculosus or A.nodosum can reduce carbohydrate digestion, however baking into bread reduces the effect.

5.
BMC Nutr ; 6: 57, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33042566

RESUMEN

BACKGROUND: A number of studies have indicated a beneficial effect of tea consumption on the reduction of risk of cognitive impairment and dementia in older aged populations. However, there is a paucity of data on these associations in the very old, defined as individuals aged 85 years and over. We investigated the relationship between tea consumption in the very old and measures of global cognitive function, memory, attention and psychomotor speed. METHOD: Longitudinal (5-years), population-based cohort study of individuals aged 85+ years in the North East of England, United Kingdom. Participants were community-dwelling and institutionalized men and women recruited through general medical practices (n = 676). Baseline tea consumption and longitudinal measures of global and domain specific (memory, speed and attention) cognitive function were assessed. Linear mixed models, controlling for demographic (e.g. age, sex and education) and health variables were used to determine whether tea consumption was protective against cognitive decline. RESULTS: Tea consumption was not associated with cognitive function at baseline on any measure (unadjusted and adjusted analyses). In the linear mixed effects models adjusted for age, sex, education and disease co-morbidity, higher tea consumption was associated with significantly better attention (focused and sustained attention), and psychomotor speed (complex tasks only) over five-years follow-up. However, there was no association between tea consumption and global cognitive function, memory or performance on simple speed tasks over time. CONCLUSIONS: In this cohort study of non-demented very old adults we found that higher (vs. lower) tea consumption was associated with better performance over time on measures of focused and sustained attention and some psychomotor speed tasks. No associations with global cognition, memory or easy speed tasks (simple Reaction Time or Word Recognition) were detected. The results have implications for the development of possible diet-based interventions focused on improving cognitive function in the very old age group. These findings need to be confirmed in a sufficiently powered and well-designed RCT with non-demented very old adults.

6.
Int J Mol Sci ; 21(18)2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32937783

RESUMEN

Parkinson's disease (PD) pathology is characterised by distinct types of cellular defects, notably associated with oxidative damage and mitochondria dysfunction, leading to the selective loss of dopaminergic neurons in the brain's substantia nigra pars compacta (SNpc). Exposure to some environmental toxicants and heavy metals has been associated with PD pathogenesis. Raised iron levels have also been consistently observed in the nigrostriatal pathway of PD cases. This study explored, for the first time, the effects of an exogenous environmental heavy metal (vanadium) and its interaction with iron, focusing on the subtoxic effects of these metals on PD-like oxidative stress phenotypes in Catecholaminergic a-differentiated (CAD) cells and PTEN-induced kinase 1 (PINK-1)B9Drosophila melanogaster models of PD. We found that undifferentiated CAD cells were more susceptible to vanadium exposure than differentiated cells, and this susceptibility was modulated by iron. In PINK-1 flies, the exposure to chronic low doses of vanadium exacerbated the existing motor deficits, reduced survival, and increased the production of reactive oxygen species (ROS). Both Aloysia citrodora Paláu, a natural iron chelator, and Deferoxamine Mesylate (DFO), a synthetic iron chelator, significantly protected against the PD-like phenotypes in both models. These results favour the case for iron-chelation therapy as a viable option for the symptomatic treatment of PD.


Asunto(s)
Hierro/metabolismo , Hierro/toxicidad , Enfermedad de Parkinson/metabolismo , Vanadio/metabolismo , Vanadio/toxicidad , Animales , Catecolaminas/metabolismo , Modelos Animales de Enfermedad , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Quelantes del Hierro/farmacología , Metales Pesados/toxicidad , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Enfermedad de Parkinson/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
7.
Contemp Clin Trials Commun ; 18: 100571, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32405570

RESUMEN

BACKGROUND: Nitrate-rich food can increase NO production and may induce positive effects on brain function. This study examined the feasibility of a randomized clinical trial (RCT) testing the effects of prolonged consumption of incremental doses of dietary nitrate (NO3 -) in overweight and obese older participants. Secondary aims tested dose-dependent changes in cognitive, vascular and pulmonary functions and cerebral blood flow (CBF). METHODS: This was a single blind, four-arm parallel RCT conducted in 60 overweight and obese older participants. Eligible participants were randomized to:1) high NO3 - (140 ml of beetroot juice (BJ) per day, ~800 mg of NO3 -/day), 2) moderate NO3 - (70 ml of BJ per day, ~400 mg of NO3 -/day), 3) low NO3 - (70 ml on alternate days, ~400 mg of NO3 -) or 4) NO3 - depleted (70 ml on alternate days, ~0.001 mg of NO3). Measurements of cognitive, vascular and pulmonary functions and CBF were conducted at baseline and 13-weeks NO3 - intake was assessed by six 24-h recalls, and by measuring NO3 - intake biomarkers. Feasibility was assessed by obtaining qualitative feedback and evaluating trial recruitment, retention, compliance with study visits and measurement protocols. RESULTS: Participant recruitment started in July 2018 and ended in April 2019. Of all the recruitment strategies that were used, advertisement of the study via Facebook generated the highest response rate. Sixty-two participants consented and were enrolled. Overall, characteristics of included participants matched our recruitment criteria. CONCLUSION: The findings from this study provide evidence of the acceptability and feasibility of an intervention investigating the effects of incremental doses of high-nitrate BJ over a prolonged period. TRIAL REGISTRATION: The intervention study was registered with clinical trial ISRCTN registry (ISRCTN14746723) on 27 December 2018.

8.
Nutrients ; 12(4)2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32326457

RESUMEN

Alzheimer's disease (AD) is characterised by the apoptosis of cholinergic neurons and the consequent attenuation of acetylcholine mediated neurotransmission, resulting in neurodegeneration. Acetyl-cholinesterase (AChE) and butyryl-cholinesterase (BuChE) are attractive therapeutic targets in the treatment of AD since inhibition of these enzymes can be used to restore synaptic concentrations of acetylcholine. Whilst inhibitors for these enzymes such as galantamine and rivastigmine have been approved for use, none are able to halt the progression of AD and are responsible for the production of troublesome side-effects. Efficacious cholinesterase inhibitors have been isolated from natural plant-based compounds with many demonstrating additional benefits beyond cholinesterase inhibition, such as antioxidation and anti-inflammation, which are key parts of AD pathology. In this study, five natural flavan-3-ol (catechin) compounds: ((-)-epicatechin (EC), catechin, (-)-epicatechin-3-gallate (ECG),) (-)-epigallocatechin (EGC), (-)-epigallocatechin-3-gallate (EGCG), isolated from green tea, were screened for their cholinesterase inhibitory activity using the Ellman assay. The kinetics of inhibition was determined using reciprocal Lineweaver-Burk plots. EGCG was the only compound found to produce statistically significant, competitive inhibition, of both AChE (p < 0.01) and BuChE (p < 0.01) with IC50 values of 0.0148 µmol/mL and 0.0251 µmol/mL respectively. These results, combined with previously identified antioxidative and anti-inflammatory properties, highlight the potential use of EGCG in the treatment of AD, provided it can be delivered to cholinergic neurons in therapeutic concentrations. Further testing of EGCG in vivo is recommended to fully characterise the pharmacokinetic properties, optimal method of administration and efficacy of this novel plant-based compound.


Asunto(s)
Acetilcolinesterasa , Enfermedad de Alzheimer/tratamiento farmacológico , Butirilcolinesterasa , Catequina/farmacología , Catequina/uso terapéutico , Inhibidores de la Colinesterasa , Fitoterapia , Té/química , Enfermedad de Alzheimer/etiología , Animales , Antiinflamatorios , Antioxidantes , Catequina/administración & dosificación , Catequina/análogos & derivados , Catequina/aislamiento & purificación , Neuronas Colinérgicas , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Anguilas , Caballos , Humanos
9.
Nutrients ; 10(8)2018 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-30087294

RESUMEN

BACKGROUND: Extracts of several members of the monoterpene-rich Lamiaceae sub-family Nepetoideae, including those from the Salvia (sage), Melissa (Lemon balm) and Rosmarinus (rosemary) genera, evince cognitive and mood effects in humans that are potentially related to their effects on cholinergic and GABAergic neurotransmission. To date, despite promising in vitro properties, the cognitive and mood effects of the closely related Mentha spicata (spearmint) and Mentha piperita (peppermint) remain unexplored. This study therefore assessed the human cognitive/mood effects of the M. spicata/piperita essential oil with the most promising, brain-relevant in vitro properties according to pre-trial in vitro screening. Design: Organic spearmint and peppermint (Mentha spicata/piperita) essential oils were pre-screened for neurotransmitter receptor binding and acetylcholinesterase (AChE) inhibition. In a double-blind, placebo-controlled, balanced cross-over study, 24 participants (mean age 25.2 years) consumed single doses of encapsulated placebo and 50 µl and 100 µl of the most promising essential oil (peppermint with nicotinic/GABAA receptor binding and AChE inhibitory properties, that increased calcium influx in a CAD cell neuronal model). Psychological functioning was assessed with mood scales and a range of standardised, cognitively demanding tasks pre-dose and at 1, 3 and 6 h post-dose. Results: The highest (100 µL) dose of essential oil improved performance on the cognitively demanding Rapid Visual Information Processing task (RVIP) at 1 h and 3 h post-dose and both doses attenuated fatigue and improved performance of the Serial 3 s subtraction task at 3 h post-dose. Conclusion: Peppermint (Mentha piperita) essential oil with high levels of menthol/menthone and characteristic in vitro cholinergic inhibitory, calcium regulatory and GABAA/nicotinic receptor binding properties, beneficially modulated performance on demanding cognitive tasks and attenuated the increase in mental fatigue associated with extended cognitive task performance in healthy adults. Future investigations should consider investigating higher doses.


Asunto(s)
Afecto/efectos de los fármacos , Encéfalo/efectos de los fármacos , Cognición/efectos de los fármacos , Mentha piperita , Nootrópicos/farmacología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Terpenos/farmacología , Adulto , Atención/efectos de los fármacos , Encéfalo/metabolismo , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Estudios Cruzados , Método Doble Ciego , Inglaterra , Femenino , Humanos , Masculino , Mentha piperita/química , Mentha spicata/química , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Pruebas Neuropsicológicas , Nootrópicos/aislamiento & purificación , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Receptores de GABA-A/efectos de los fármacos , Receptores de GABA-A/metabolismo , Receptores Nicotínicos/efectos de los fármacos , Receptores Nicotínicos/metabolismo , Terpenos/aislamiento & purificación , Adulto Joven
10.
J Psychopharmacol ; 31(2): 211-221, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28168925

RESUMEN

The present study compared the cognitive and mood effects of two commercially available products, Red Bull energy drink 250 mL and Red Bull Sugarfree energy drink 250 mL, together with a matching placebo 250 mL. Twenty-four healthy young volunteers took part in a randomised, placebo controlled, double-blind, three-way cross-over study. Cognitive function was assessed using an integrated set of nine computerised tests of attention, working and episodic memory. On each study day the volunteers received a standardised breakfast prior to completing a baseline performance on cognitive tests and mood scales, followed by the consumption of the study drink. The cognitive tests and scales were then re-administered at 30, 60 and 90 min post-dose. Red Bull was found to produce significant improvements over both the Sugarfree version and the placebo drink on two composite scores from the six working and episodic memory tests; one combining the 12 accuracy measures from the six tasks and the other the average speed of correct responses from the working memory and episodic recognition memory tasks. These improvements were in the range of a medium effect size, which reflects a substantial enhancement to memory in young volunteers.


Asunto(s)
Afecto/efectos de los fármacos , Cognición/efectos de los fármacos , Adulto , Atención/efectos de los fármacos , Cafeína/administración & dosificación , Estudios Cruzados , Método Doble Ciego , Bebidas Energéticas , Femenino , Glucosa/administración & dosificación , Voluntarios Sanos , Humanos , Masculino , Memoria/efectos de los fármacos , Vitaminas/administración & dosificación , Adulto Joven
11.
Nutr Neurosci ; 19(5): 196-205, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25714035

RESUMEN

OBJECTIVES: Tea has been associated with many mental benefits, such as attention enhancement, clarity of mind, and relaxation. These psychosomatic states can be measured in terms of brain activity using an electroencephalogram (EEG). Brain activity can be assessed either during a state of passive activity or when performing attention tasks and it can provide useful information about the brain's state. This study investigated the effects of green and black consumption on brain activity as measured by a simplified EEG, during passive activity. METHODS: Eight healthy volunteers participated in the study. The EEG measurements were performed using a two channel EEG brain mapping instrument - HeadCoach™. Fast Fourier transform algorithm and EEGLAB toolbox using the Matlab software were used for data processing and analysis. RESULTS: Alpha, theta, and beta wave activities were all found to increase after 1 hour of green and black tea consumption, albeit, with very considerable inter-individual variations. DISCUSSION: Our findings provide further evidence for the putative beneficial effects of tea. The highly significant increase in theta waves (P < 0.004) between 30 minutes and 1 hour post-consumption of green tea may be an indication of its putative role in cognitive function, specifically alertness and attention. There were considerable inter-individual variations in response to the two teas which may be due genetic polymorphisms in metabolism and/or influence of variety/blend, dose and content of the selected products whose chemistry and therefore efficacy will have been influenced by 'from field to shelf practices'.


Asunto(s)
Atención , Ondas Encefálicas , Cognición , Manipulación de Alimentos , , Regulación hacia Arriba , Adulto , Ritmo alfa , Ritmo beta , Estudios Cruzados , Electroencefalografía , Inglaterra , Estudios de Factibilidad , Femenino , Análisis de Fourier , Humanos , Masculino , Oxidación-Reducción , Reproducibilidad de los Resultados , Té/química , Ritmo Teta
12.
Int J Med Mushrooms ; 17(2): 117-28, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25746617

RESUMEN

The objective of this study was to quantify a number of bioactive compounds and antioxidant activity of the oyster mushroom, Pleurotus. Ostreatus, and characterize the effects of processing, such as blanching, on these outcomes. Dry matter content was 8%. Lovastatin was not detected in this study. ß-glucan content of 23.9% and total polyphenol content of 487.12 mg gallic acid equivalent/100 g of dry matter were obtained in raw P. ostreatus. Antioxidant activities as evaluated by 1,1-diphenyl-2-picrylhydrazyl, Trolox equivalent antioxidant capacity, and ferric reducing antioxidant power assays in raw P. ostreatus were 14.46, 16.51, and 11.21 µmol/g, respectively. Blanching did not significantly affect ß-glucan content but caused significant decrease in dry matter content, polyphenol content, and antioxidant activities. Mushroom rolls produced from blanched mushrooms and blanching water contained significantly higher amounts of ß-glucan, total polyphenol content, and FRAP antioxidant activity compared to blanched mushrooms. In conclusion, P. ostreatus is a good source for ß-glucan, dietary polyphenols, and antioxidants. Although the blanching process could affect these properties, re-addition of the blanching water during the production process of mushroom rolls could potentially recover these properties and is therefore recommended.


Asunto(s)
Antioxidantes/farmacología , Productos Biológicos/farmacología , Polisacáridos Fúngicos/farmacología , Lovastatina/farmacología , Pleurotus/química , Polifenoles/farmacología , beta-Glucanos/farmacología , Agaricales , Antioxidantes/análisis , Compuestos de Bifenilo/metabolismo , Polisacáridos Fúngicos/análisis , Lovastatina/análisis , Oxidación-Reducción , Picratos/metabolismo , Polifenoles/análisis , beta-Glucanos/análisis
13.
Subcell Biochem ; 65: 295-326, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23225009

RESUMEN

Amyloid-ß (Aß) fibrillogenesis and associated cyto/neurotoxicity are major pathological events and hallmarks in diseases such as Alzheimer's disease (AD). The understanding of Aß molecular pathogenesis is currently a pharmacological target for rational drug design and discovery based on reduction of Aß generation, inhibition of Aß fibrillogenesis and aggregation, enhancement of Aß clearance and amelioration of associated cytotoxicity. Molecular mechanisms for other amyloidoses, such as transthyretin amyloidosis, AL-amyloidosis, as well as α-synuclein and prion protein are also pharmacological targets for current drug therapy, design and discovery. We report on natural herbal compounds and extracts that are capable binding to and inhibiting different targets associated with AD and other amyloid-associated diseases, providing a basis for future therapeutic strategies. Many herbal compounds, including curcumin, galantamine, quercetin and other polyphenols, are under active investigation and hold considerable potential for future prophylactic and therapeutic treatment against AD and other neurodegenerative diseases, as well as systemic amyloid diseases. A common emerging theme throughout many studies is the anti-oxidant and anti-inflammatory properties of the compounds or herbal extracts under investigation, within the context of the inhibition of cyto/neurotoxicity and anti-amyloid activity.


Asunto(s)
Enfermedad de Alzheimer , Neuropatías Amiloides Familiares , Precursor de Proteína beta-Amiloide , Complejos Multiproteicos , Extractos Vegetales , Priones , alfa-Sinucleína , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Neuropatías Amiloides Familiares/tratamiento farmacológico , Neuropatías Amiloides Familiares/metabolismo , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Descubrimiento de Drogas , Humanos , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Péptidos/química , Péptidos/metabolismo , Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Priones/química , Priones/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo
14.
Food Funct ; 3(6): 651-61, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22418730

RESUMEN

By 2034 it is forecast that 5% of the global population will be aged 85 years or over--approximately two and half fold increase on present day figures--which will inevitably lead to an increase in age-associated disorders such as Alzheimer's disease. There is mounting evidence that green tea (Camellia sinensis) possesses numerous health-promoting properties, and may potentially be beneficial to those suffering from Alzheimer's and other diseases, including cardiovascular disease and cancer. These beneficial properties are largely attributed to the high polyphenol content, particularly the catechins. In this study, we measured acetylcholinesterase inhibition by white and green teas and their simulated intestinal digests. We found that the potency with which the white and green tea extracts inhibited acetylcholinesterase varied through the simulated digestion procedure. Initially, in the undigested extract form, potency was high with IC50 values of 7.20 µg mL⁻¹ and 8.06 µg mL⁻¹ for green and white tea respectively.However, this decreased significantly after gastric digestion but activity was recovered after pancreatic digestion which could be related to relative increases in the levels of caffeine and specific phenolic components. Of the pure tea compounds tested, EGCG was the most potent with an IC50 of 0.0096 µmol mL⁻¹ but its breakdown product; γ-valerolactone was the least potent analyte. Particularly interesting were the results of caffeine,which exhibited a strong inhibitory activity and pyrogallol, which recorded a much stronger potency than its parent compound gallic acid, suggesting a pro-drug-like relationship. Overall, the results indicate that further research is necessary to determine the full potential of digestion of tea and its metabolites and how inter-individual variation may indicate that some sections of society could potentially benefit more from drinking tea as a strategy to prevent the development of dementia. We have also shown the activities of a number of metabolites,however, further research is required to determine their potential bioavailability.


Asunto(s)
Acetilcolinesterasa/metabolismo , Camellia sinensis/química , Inhibidores de la Colinesterasa/farmacología , Regulación hacia Abajo/efectos de los fármacos , Intestinos/efectos de los fármacos , Extractos Vegetales/farmacología , Té/química , Acetilcolinesterasa/genética , Inhibidores de la Colinesterasa/metabolismo , Digestión/efectos de los fármacos , Humanos , Intestinos/enzimología , Intestinos/fisiología , Extractos Vegetales/metabolismo
15.
Phytother Res ; 26(1): 113-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21567509

RESUMEN

The ability of an aqueous extract of W. somnifera L. Dunal (Family: Solanaceae) roots to inhibit fibril formation by the amyloid-ß peptide in vitro was investigated. W. somnifera is used extensively in traditional Ayurvedic medicine as a nerve tonic with reputed memory enhancing properties. Inhibition of fibrillogenesis measured by transmission electron microscopy and ThT fluorescence assay showed that an aqueous extract of W. somnifera strongly inhibited Aß fibril formation in a concentration-dependent manner, when compared with control samples. These results suggest that the aqueous extract of W. somnifera root has an ability to inhibit the formation of mature amyloid-ß fibrils in vitro, which are known to lead to amyloid plaque formation in vivo.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Amiloide/efectos de los fármacos , Extractos Vegetales/farmacología , Placa Amiloide/prevención & control , Withania , Amiloide/biosíntesis , Células Cultivadas , Relación Dosis-Respuesta a Droga , Fluorescencia , Medicina Ayurvédica , Microscopía Electrónica de Transmisión , Fitoterapia , Extractos Vegetales/uso terapéutico , Raíces de Plantas , Placa Amiloide/metabolismo
16.
J Psychopharmacol ; 25(8): 1088-100, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20937617

RESUMEN

Extracts of sage (Salvia officinalis/lavandulaefolia) with terpenoid constituents have previously been shown to inhibit cholinesterase and improve cognitive function. The current study combined an in vitro investigation of the cholinesterase inhibitory properties and phytochemical constituents of a S. lavandulaefolia essential oil, with a double-blind, placebo-controlled, balanced crossover study assessing the effects of a single dose on cognitive performance and mood. In this latter investigation 36 healthy participants received capsules containing either 50 µL of the essential oil or placebo on separate occasions, 7 days apart. Cognitive function was assessed using a selection of computerized memory and attention tasks and the Cognitive Demand Battery before the treatment and 1-h and 4-h post-dose. The essential oil was a potent inhibitor of human acetylcholinesterase (AChE) and consisted almost exclusively of monoterpenoids. Oral consumption lead to improved performance of secondary memory and attention tasks, most notably at the 1-h post-dose testing session, and reduced mental fatigue and increased alertness which were more pronounced 4-h post-dose. These results extend previous observations of improved cognitive performance and mood following AChE inhibitory sage extracts and suggest that the ability of well-tolerated terpenoid-containing extracts to beneficially modulate cholinergic function and cognitive performance deserves further attention.


Asunto(s)
Afecto/efectos de los fármacos , Cognición/efectos de los fármacos , Aceites Volátiles/farmacología , Salvia/química , Adulto , Atención/efectos de los fármacos , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Memoria/efectos de los fármacos , Terpenos/aislamiento & purificación , Terpenos/farmacología , Adulto Joven
17.
Am J Clin Nutr ; 91(6): 1590-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20357044

RESUMEN

BACKGROUND: The many putative beneficial effects of the polyphenol resveratrol include an ability to bolster endogenous antioxidant defenses, modulate nitric oxide synthesis, and promote vasodilation, which thereby improves blood flow. Resveratrol may therefore modulate aspects of brain function in humans. OBJECTIVE: The current study assessed the effects of oral resveratrol on cognitive performance and localized cerebral blood flow variables in healthy human adults. DESIGN: In this randomized, double-blind, placebo-controlled, crossover study, 22 healthy adults received placebo and 2 doses (250 and 500 mg) of trans-resveratrol in counterbalanced order on separate days. After a 45-min resting absorption period, the participants performed a selection of cognitive tasks that activate the frontal cortex for an additional 36 min. Cerebral blood flow and hemodynamics, as indexed by concentration changes in oxygenated and deoxygenated hemoglobin, were assessed in the frontal cortex throughout the posttreatment period with the use of near-infrared spectroscopy. The presence of resveratrol and its conjugates in plasma was confirmed by HPLC after the same doses in a separate cohort (n = 9). RESULTS: Resveratrol administration resulted in dose-dependent increases in cerebral blood flow during task performance, as indexed by total concentrations of hemoglobin. There was also an increase in deoxyhemoglobin after both doses of resveratrol, which suggested enhanced oxygen extraction, that became apparent toward the end of the 45-min absorption phase and was sustained throughout task performance. Cognitive function was not affected. Resveratrol metabolites were present in plasma throughout the cognitive task period. CONCLUSION: These results showed that single doses of orally administered resveratrol can modulate cerebral blood flow variables.


Asunto(s)
Circulación Cerebrovascular/efectos de los fármacos , Cognición/efectos de los fármacos , Lóbulo Frontal/irrigación sanguínea , Estilbenos/farmacología , Adolescente , Adulto , Cognición/fisiología , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Hemoglobinas/metabolismo , Humanos , Masculino , Resveratrol , Espectroscopía Infrarroja Corta , Estilbenos/sangre , Vasodilatadores/sangre , Vasodilatadores/farmacología , Adulto Joven
18.
Neurosci Lett ; 442(3): 297-9, 2008 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-18640242

RESUMEN

There is evidence to suggest an involvement of the K variant of the butyrylcholinesterase gene (BCHE) in dementia. We have examined the relationship between BCHE genotype and butyrylcholinesterase (BuChE) activity in autopsy brain tissue. We studied 164 autopsy cases, 144 with dementia and 20 controls, including 13 K homozygotes and 48 K heterozygotes, from three centres: Newcastle, Oxford and London. Mean BuChE activity in temporal cortex was 37% higher in K homozygotes than in wild-type homozygotes. Linear regression analysis, controlling for gender, diagnosis, age at death and study centre, showed that the number of BCHE-K alleles was associated with increasing BuChE activity (p=0.009).


Asunto(s)
Butirilcolinesterasa/genética , Demencia/genética , Lóbulo Temporal/enzimología , Anciano , Anciano de 80 o más Años , Demencia/enzimología , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
19.
Ann N Y Acad Sci ; 1149: 23-6, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19120167

RESUMEN

The use of synthetic products in veterinary pest management is becoming increasingly problematic. Issues, including pest resistance, product withdrawal, undesirable environmental persistence, and high mammalian toxicity associated with synthetic pesticides, are driving research to identify new pest management approaches. One approach employs the repellent/toxic effects of plant-derived products (PDPs). Several pesticides based on PDPs are already available in some areas of pest management. This review highlights instances in which such products have been used with success against pests of domestic animals, livestock, apiculture, and poultry.


Asunto(s)
Vectores Artrópodos , Aceites Volátiles/uso terapéutico , Enfermedades Parasitarias en Animales/prevención & control , Control de Plagas , Aceites de Plantas/uso terapéutico , Animales , Enfermedades Parasitarias en Animales/transmisión
20.
Neuropsychopharmacology ; 31(4): 845-52, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16205785

RESUMEN

Salvia officinalis (sage) has previously been shown both to possess in vitro cholinesterase inhibiting properties, and to enhance mnemonic performance and improve mood in healthy young participants. In this double-blind, placebo-controlled, crossover study, 30 healthy participants attended the laboratory on three separate days, 7 days apart, receiving a different treatment in counterbalanced order on each occasion (placebo, 300, 600 mg dried sage leaf). On each day mood was assessed predose and at 1 and 4 h postdose. Each mood assessment comprised completion of Bond-Lader mood scales and the State Trait Anxiety Inventory (STAI) before and after 20 min performance of the Defined Intensity Stress Simulator (DISS) computerized multitasking battery. In a concomitant investigation, an extract of the sage leaf exhibited dose-dependent, in vitro inhibition of acetylcholinesterase and, to a greater extent, butyrylcholinesterase. Both doses of sage led to improved ratings of mood in the absence of the stressor (that is, in pre-DISS mood scores) postdose, with the lower dose reducing anxiety and the higher dose increasing 'alertness', 'calmness' and 'contentedness' on the Bond-Lader mood scales. The reduced anxiety effect following the lower dose was, however, abolished by performing the DISS, with the same dose also being associated with a reduction of alertness during performance. Task performance on the DISS battery was improved for the higher dose at both postdose sessions, but reduced for the lower dose at the later testing session. The results confirm previous observations of the cholinesterase inhibiting properties of S. officinalis, and improved mood and cognitive performance following the administration of single doses to healthy young participants.


Asunto(s)
Afecto/efectos de los fármacos , Ansiedad/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Salvia officinalis/química , Estrés Psicológico/tratamiento farmacológico , Adulto , Análisis de Varianza , Inhibidores de la Colinesterasa/aislamiento & purificación , Inhibidores de la Colinesterasa/farmacología , Colinesterasas/metabolismo , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Matemática , Inventario de Personalidad/estadística & datos numéricos , Pruebas Psicológicas/estadística & datos numéricos , Desempeño Psicomotor/efectos de los fármacos , Factores de Tiempo , Resultado del Tratamiento
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