1
|
Gonçalves JS, Marçal AL, Marques BS, Costa FD, Laranjinha J, Rocha BS, Lourenço CF. Dietary nitrate supplementation and cognitive health: the nitric oxide-dependent neurovascular coupling hypothesis. Biochem Soc Trans 2024; 52:279-289. [PMID: 38385536 DOI: 10.1042/bst20230491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/23/2024]
Abstract
Diet is currently recognized as a major modifiable agent of human health. In particular, dietary nitrate has been increasingly explored as a strategy to modulate different physiological mechanisms with demonstrated benefits in multiple organs, including gastrointestinal, cardiovascular, metabolic, and endocrine systems. An intriguing exception in this scenario has been the brain, for which the evidence of the nitrate benefits remains controversial. Upon consumption, nitrate can undergo sequential reduction reactions in vivo to produce nitric oxide (•NO), a ubiquitous paracrine messenger that supports multiple physiological events such as vasodilation and neuromodulation. In the brain, •NO plays a key role in neurovascular coupling, a fine process associated with the dynamic regulation of cerebral blood flow matching the metabolic needs of neurons and crucial for sustaining brain function. Neurovascular coupling dysregulation has been associated with neurodegeneration and cognitive dysfunction during different pathological conditions and aging. We discuss the potential biological action of nitrate on brain health, concerning the molecular mechanisms underpinning this association, particularly via modulation of •NO-dependent neurovascular coupling. The impact of nitrate supplementation on cognitive performance was scrutinized through preclinical and clinical data, suggesting that intervention length and the health condition of the participants are determinants of the outcome. Also, it stresses the need for multimodal quantitative studies relating cellular and mechanistic approaches to function coupled with behavior clinical outputs to understand whether a mechanistic relationship between dietary nitrate and cognitive health is operative in the brain. If proven, it supports the exciting hypothesis of cognitive enhancement via diet.
Collapse
Affiliation(s)
- João S Gonçalves
- Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Ana L Marçal
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Bárbara S Marques
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Filipa D Costa
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - João Laranjinha
- Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Bárbara S Rocha
- Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Cátia F Lourenço
- Center for Neuroscience and Cell Biology, University of Coimbra, Rua Larga 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Health Science Campus, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| |
Collapse
|
2
|
de Crom TOE, Blekkenhorst L, Vernooij MW, Ikram MK, Voortman T, Ikram MA. Dietary nitrate intake in relation to the risk of dementia and imaging markers of vascular brain health: a population-based study. Am J Clin Nutr 2023; 118:352-359. [PMID: 37536866 DOI: 10.1016/j.ajcnut.2023.05.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/16/2023] [Accepted: 05/22/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND Nitric oxide is a free radical that can be produced from dietary nitrate and positively affects cardiovascular health. With cardiovascular health playing an important role in the etiology of dementia, we hypothesized a link between dietary nitrate intake and the risk of dementia. OBJECTIVES This study aimed to find the association of total, vegetable, and nonvegetable dietary nitrate intake with the risk of dementia and imaging markers of vascular brain health, such as total brain volume, global cerebral perfusion, white matter hyperintensity volume, microbleeds, and lacunar infarcts. METHODS Between 1990 and 2009, dietary intake was assessed using food-frequency questionnaires in 9543 dementia-free participants (mean age, 64 y; 58% female) from the prospective population-based Rotterdam Study. Participants were followed up for incidence dementia until January 2020. We used Cox models to determine the association between dietary nitrate intake and incident dementia. Using linear mixed models and logistic regression models, we assessed the association of dietary nitrate intake with changes in imaging markers across 3 consecutive examination rounds (mean interval between images 4.6 y). RESULTS Participants median dietary nitrate consumption was 85 mg/d (interquartile range, 55 mg/d), derived on average for 81% from vegetable sources. During a mean follow-up of 14.5 y, 1472 participants developed dementia. A higher intake of total and vegetable dietary nitrate was associated with a lower risk of dementia per 50-mg/d increase [hazard ratio (HR): 0.92; 95% confidence interval (CI): 0.87, 0.98; and HR: 0.92; 95% CI: 0.86, 0.97, respectively] but not with changes in neuroimaging markers. No association between nonvegetable dietary nitrate intake and the risk of dementia (HR: 1.15; 95% CI: 0.64, 2.07) or changes in neuroimaging markers were observed. CONCLUSIONS A higher dietary nitrate intake from vegetable sources was associated with a lower risk of dementia. We found no evidence that this association was driven by vascular brain health.
Collapse
Affiliation(s)
- Tosca O E de Crom
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Lauren Blekkenhorst
- Nutrition and Health Innovation Research Institute, School of Medical and Health Sciences, Edith Cowan University, Royal Perth Hospital Research Foundation, Perth, Western Australia, Australia
| | - Meike W Vernooij
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, Netherlands; Department of Radiology and Nuclear Medicine, Erasmus University Medical Center, Rotterdam, Netherlands
| | - M Kamran Ikram
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, Netherlands; Department of Neurology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Trudy Voortman
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus University Medical Center, Rotterdam, Netherlands.
| |
Collapse
|
3
|
Gamage E, Orr R, Travica N, Lane MM, Jacka F, Dissanayaka T, Kim JH, Grosso G, Godos J, Marx W. Polyphenols as novel interventions for depression: exploring the efficacy, mechanisms of action, and implications for future research. Neurosci Biobehav Rev 2023; 151:105225. [PMID: 37164045 DOI: 10.1016/j.neubiorev.2023.105225] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 04/29/2023] [Accepted: 05/06/2023] [Indexed: 05/12/2023]
Abstract
Numerous animal and human studies have assessed the relationship between polyphenols and outcomes related to depression. However, no comprehensive synthesis of the main findings has been conducted. The aim of this manuscript was to systematically review the available evidence from animal and human studies on the association and the effects of dietary polyphenols on depression and provide recommendations for future research. We based our review on 163 preclinical animal, 16 observational and 44 intervention articles assessing the relationship between polyphenols and outcomes related to depression. Most animal studies demonstrated that exposure to polyphenols alleviated behaviours reported to be associated with depression. However, human studies are less clear, with some studies reporting and inverse relationship between the intake of some polyphenols, and polyphenol rich foods and depression risk and symptoms, while others reporting no association or effect. Hence, while there has been extensive research conducted in animals and there is some supporting evidence in humans, further human studies are required, particularly in younger and clinical populations.
Collapse
Affiliation(s)
- Elizabeth Gamage
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Rebecca Orr
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Nikolaj Travica
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Melissa M Lane
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Felice Jacka
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Thusharika Dissanayaka
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Jee H Kim
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| | - Giuseppe Grosso
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Justyna Godos
- Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy
| | - Wolfgang Marx
- Deakin University, IMPACT - the Institute for Mental and Physical Health and Clinical Translation, Food & Mood Centre, School of Medicine, Barwon Health, Geelong, Australia
| |
Collapse
|
4
|
Cheng N, Bell L, Lamport DJ, Williams CM. Dietary Flavonoids and Human Cognition: A Meta-Analysis. Mol Nutr Food Res 2022; 66:e2100976. [PMID: 35333451 PMCID: PMC9787524 DOI: 10.1002/mnfr.202100976] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/09/2022] [Indexed: 12/30/2022]
Abstract
Improving cognition is important in all age groups, from performance in school examinations to prevention of cognitive decline in later life. Dietary polyphenols, in particular flavonoids, have been examined for their benefits to cognitive outcomes. This meta-analysis evaluates the effects of dietary flavonoids on cognition across the lifespan. In January 2020 databases were searched for randomized controlled trials investigating flavonoid effects on human cognition. Eighty studies, comprising 5519 participants, were included in the final meta-analysis. The global analysis indicates dietary flavonoids induced significant benefit to cognitive performance (g = 0.148, p < 0.001), with subgroup analyses revealing that cocoa (g = 0.224, p = 0.036), ginkgo (g = 0.187, p ≤ 0.001), and berries (g = 0.149, p = 0.009) yielded the most notable improvements. Significant benefits were observed from chronic studies, in middle-aged and older adults, and with low and medium doses. The domains of long-term memory, processing speed, and mood showed sensitivity to flavonoid intervention. This meta-analysis provides evidence for the positive effects of flavonoids on cognition and highlights several moderating factors. Flavonoid-based dietary interventions therefore potentially offer a highly accessible, safe, and cost-effective treatment to help tackle the burden of cognitive decline.
Collapse
Affiliation(s)
- Nancy Cheng
- School of Psychology and Clinical Language SciencesUniversity of Reading, ReadingUK
| | - Lynne Bell
- School of Psychology and Clinical Language SciencesUniversity of Reading, ReadingUK
| | - Daniel J. Lamport
- School of Psychology and Clinical Language SciencesUniversity of Reading, ReadingUK
| | - Claire M. Williams
- School of Psychology and Clinical Language SciencesUniversity of Reading, ReadingUK
| |
Collapse
|
5
|
Gardener SL, Rainey-Smith SR, Weinborn M, Bondonno CP, Martins RN. Intake of Products Containing Anthocyanins, Flavanols, and Flavanones, and Cognitive Function: A Narrative Review. Front Aging Neurosci 2021; 13:640381. [PMID: 34539375 PMCID: PMC8446387 DOI: 10.3389/fnagi.2021.640381] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 07/21/2021] [Indexed: 11/13/2022] Open
Abstract
The purpose of this review is to examine human research studies published within the past 6 years which evaluate the role of anthocyanin, flavanol, and flavanone consumption in cognitive function, and to discuss potential mechanisms of action underlying any observed benefits. Evidence to date suggests the consumption of flavonoid-rich foods, such as berries and cocoa, may have the potential to limit, or even reverse, age-related declines in cognition. Over the last 6 years, the flavonoid subgroups of anthocyanins, flavanols, and flavanones have been shown to be beneficial in terms of conferring neuroprotection. The mechanisms by which flavonoids positively modulate cognitive function are yet to be fully elucidated. Postulated mechanisms include both direct actions such as receptor activation, neurotrophin release and intracellular signaling pathway modulation, and indirect actions such as enhancement of cerebral blood flow. Further intervention studies conducted in diverse populations with sufficient sample sizes and long durations are required to examine the effect of consumption of flavonoid groups on clinically relevant cognitive outcomes. As populations continue to focus on adopting healthy aging strategies, dietary interventions with flavonoids remains a promising avenue for future research. However, many questions are still to be answered, including identifying appropriate dosage, timeframes for intake, as well as the best form of flavonoids, before definitive conclusions can be drawn about the extent to which their consumption can protect the aging brain.
Collapse
Affiliation(s)
- Samantha L Gardener
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Australian Alzheimer's Research Foundation, Ralph and Patricia Sarich Neuroscience Research Institute, Nedlands, WA, Australia
| | - Stephanie R Rainey-Smith
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Australian Alzheimer's Research Foundation, Ralph and Patricia Sarich Neuroscience Research Institute, Nedlands, WA, Australia.,Centre for Healthy Ageing, Health Futures Institute, Murdoch University, Murdoch, WA, Australia.,School of Psychological Science, The University of Western Australia, Crawley, WA, Australia
| | - Michael Weinborn
- School of Psychological Science, The University of Western Australia, Crawley, WA, Australia
| | - Catherine P Bondonno
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Medical School, Royal Perth Hospital, The University of Western Australia, Perth, WA, Australia
| | - Ralph N Martins
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Australian Alzheimer's Research Foundation, Ralph and Patricia Sarich Neuroscience Research Institute, Nedlands, WA, Australia.,Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| |
Collapse
|
6
|
Shannon OM, Easton C, Shepherd AI, Siervo M, Bailey SJ, Clifford T. Dietary nitrate and population health: a narrative review of the translational potential of existing laboratory studies. BMC Sports Sci Med Rehabil 2021; 13:65. [PMID: 34099037 PMCID: PMC8186051 DOI: 10.1186/s13102-021-00292-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 05/26/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND Dietary inorganic nitrate (NO3-) is a polyatomic ion, which is present in large quantities in green leafy vegetables and beetroot, and has attracted considerable attention in recent years as a potential health-promoting dietary compound. Numerous small, well-controlled laboratory studies have reported beneficial health effects of inorganic NO3- consumption on blood pressure, endothelial function, cerebrovascular blood flow, cognitive function, and exercise performance. Translating the findings from small laboratory studies into 'real-world' applications requires careful consideration. MAIN BODY This article provides a brief overview of the existing empirical evidence basis for the purported health-promoting effects of dietary NO3- consumption. Key areas for future research are then proposed to evaluate whether promising findings observed in small animal and human laboratory studies can effectively translate into clinically relevant improvements in population health. These proposals include: 1) conducting large-scale, longer duration trials with hard clinical endpoints (e.g. cardiovascular disease incidence); 2) exploring the feasibility and acceptability of different strategies to facilitate a prolonged increase in dietary NO3- intake; 3) exploitation of existing cohort studies to explore associations between NO3- intake and health outcomes, a research approach allowing larger samples sizes and longer duration follow up than is feasible in randomised controlled trials; 4) identifying factors which might account for individual differences in the response to inorganic NO3- (e.g. sex, genetics, habitual diet) and could assist with targeted/personalised nutritional interventions; 5) exploring the influence of oral health and medication on the therapeutic potential of NO3- supplementation; and 6) examining potential risk of adverse events with long term high- NO3- diets. CONCLUSION The salutary effects of dietary NO3- are well established in small, well-controlled laboratory studies. Much less is known about the feasibility and efficacy of long-term dietary NO3- enrichment for promoting health, and the factors which might explain the variable responsiveness to dietary NO3- supplementation between individuals. Future research focussing on the translation of laboratory data will provide valuable insight into the potential applications of dietary NO3- supplementation to improve population health.
Collapse
Affiliation(s)
- Oliver M Shannon
- Human Nutrition Research Centre, Population Health Sciences Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Chris Easton
- Institute for Clinical Exercise and Health Science, University of the West of Scotland, Blantyre, Scotland, UK
| | - Anthony I Shepherd
- School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Mario Siervo
- School of Life Sciences, The University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Tom Clifford
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK.
| |
Collapse
|
7
|
Hepsomali P, Greyling A, Scholey A, Vauzour D. Acute Effects of Polyphenols on Human Attentional Processes: A Systematic Review and Meta-Analysis. Front Neurosci 2021; 15:678769. [PMID: 34108860 PMCID: PMC8180591 DOI: 10.3389/fnins.2021.678769] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/26/2021] [Indexed: 12/17/2022] Open
Abstract
Background: The effects of polyphenols on cognitive functions have been extensively studied. Due to the large heterogeneity in the study designs, however, it is often difficult to interpret their efficacy. To address this issue, we conducted a systematic review and meta-analyses to examine whether acute polyphenol intake may have a beneficial effect on cognition and specifically on the accuracy and speed of attention. Methods: PubMed and Scopus databases were systematically searched for studies published up to end of August 2020 following PRISMA guidelines (PROSPERO registration number: CRD42021232109). Only placebo-controlled human intervention trials that assessed acute effects of polyphenols on accuracy and speed of attention were included in the meta-analyses. When cognitive tasks were repeated over time, pooled means and standard deviations for intervention and placebo over repetitions separately for each task for both speed and accuracy were calculated. We also conducted separate analyses focusing only on the last repetition. Furthermore, confounding effects of age and source of polyphenols were also considered. Results: Eighteen studies met the inclusion criteria. The pooled analysis of last task repetitions showed that the acute consumption of polyphenols improved rapid visual information processing speed in young participants (SMD = 0.26; 95%CI = [0.03-0.50]; I 2= 0%; p = 0.02; k = 5). All other analyses did not reach significance. Conclusion: The results of the current study indicate that acute polyphenol consumption might improve speed in rapid visual information processing task, a higher order task with elements of vigilance, working memory, and executive function, in young participants; however, as the current literature is inconsistent and limited, further acute intervention studies are warranted to achieve more conclusive results.
Collapse
Affiliation(s)
- Piril Hepsomali
- Unilever R&D, Colworth Science Park, Bedford, United Kingdom
| | - Arno Greyling
- Unilever Foods Innovation Centre, Wageningen, Netherlands
| | - Andrew Scholey
- Nutrition, Dietetics and Food, Monash University, Notting Hill, VIC, Australia
| | - David Vauzour
- Department of Nutrition and Preventive Medicine, Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| |
Collapse
|
8
|
White N, Kouwenhoven M, Machado L. Short-Term Retest Performance in Young versus Older Adults: Consideration of Integrated Speed-Accuracy Measures. Exp Aging Res 2021; 48:68-85. [PMID: 33993852 DOI: 10.1080/0361073x.2021.1919475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Objectives: The current research addressed gaps in the literature regarding short-term computerized cognitive retest performance in young and older adults using two integrated speed-accuracy metrics. The aims were: (a) to advance the aging literature on short-term retest performance using a computerized cognitive battery and a retest schedule that included both within- and between-day time points, and (b) to assess the test-retest reliability of two integrated speed-accuracy metrics, inverse efficiency scores (IES) and balanced integration scores (BIS).Method: Twenty young (18-23 years) and thirty older (65-71 years) men completed a battery measuring a range of cognitive functions, six times over three testing days, each 1 week apart.Results: Compared to young adults, older adults exhibited steeper within- and between-day performance gains in IES and BIS, which may reflect a combination of lower initial cognitive ability and familiarity, indicating that older adults may require more familiarization on computerized tests. Relative to unadjusted reaction times, IES reliability appeared comparable in older adults, but slightly lower among young adults. The reliability of BIS was lower than unadjusted reaction times and IES in both age groups.Discussion: Our findings provide guidance for researchers wanting to combine speed and accuracy into a single performance metric in repeated testing contexts.
Collapse
Affiliation(s)
- Naomi White
- Department of Psychology, University of Otago, Dunedin, New Zealand.,Brain Research New Zealand, Auckland, New Zealand
| | | | - Liana Machado
- Department of Psychology, University of Otago, Dunedin, New Zealand.,Brain Research New Zealand, Auckland, New Zealand
| |
Collapse
|
9
|
Plant Foods Rich in Antioxidants and Human Cognition: A Systematic Review. Antioxidants (Basel) 2021; 10:antiox10050714. [PMID: 33946461 PMCID: PMC8147117 DOI: 10.3390/antiox10050714] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/28/2021] [Accepted: 04/29/2021] [Indexed: 12/14/2022] Open
Abstract
Oxidative stress can compromise central nervous system integrity, thereby affecting cognitive ability. Consumption of plant foods rich in antioxidants could thereby protect cognition. We systematically reviewed the literature exploring the effects of antioxidant-rich plant foods on cognition. Thirty-one studies were included: 21 intervention, 4 cross-sectional (one with a cohort in prospective observation as well), and 6 prospective studies. Subjects belonged to various age classes (young, adult, and elderly). Some subjects examined were healthy, some had mild cognitive impairment (MCI), and some others were demented. Despite the different plant foods and the cognitive assessments used, the results can be summarized as follows: 7 studies reported a significant improvement in all cognitive domains examined; 19 found significant improvements only in some cognitive areas, or only for some food subsets; and 5 showed no significant improvement or no effectiveness. The impact of dietary plant antioxidants on cognition appears promising: most of the examined studies showed associations with significant beneficial effects on cognitive functions-in some cases global or only in some specific domains. There was typically an acute, preventive, or therapeutic effect in young, adult, and elderly people, whether they were healthy, demented, or affected by MCI. Their effects, however, are not attributable only to anti-oxidation.
Collapse
|
10
|
Ong S, Bondonno NP, Downey LA, Scholey A, Smith MA, Stough C, Blekkenhorst LC, Woodman R, Croft KD, Hodgson JM, Bondonno CP. Effects of Chewing Gum on Nitric Oxide Metabolism, Markers of Cardiovascular Health and Neurocognitive Performance after a Nitrate-Rich Meal. J Am Coll Nutr 2021; 41:178-190. [PMID: 33600287 DOI: 10.1080/07315724.2020.1869119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
OBJECTIVES Cardiovascular and neurocognitive responses to chewing gum have been reported, but the mechanisms are not well understood. Chewing gum after a nitrate-rich meal may upregulate the reduction of oral nitrate to nitrite and increase nitric oxide (NO), a molecule important to cardiovascular and neurocognitive health. We aimed to explore effects of chewing gum after a nitrate-rich meal on nitrate metabolism (through the enterosalivary nitrate-nitrite-NO pathway), endothelial function, blood pressure (BP), neurocognitive performance, mood and anxiety. METHODS Twenty healthy men (n = 6) and women (n = 14) with a mean age of 48 years (range: 23-69) were recruited to a randomized controlled cross-over trial. After consumption of a nitrate-rich meal (180 mg of nitrate), we assessed the acute effects of chewing gum, compared to no gum chewing, on (i) salivary nitrate, nitrite and the nitrate reductase ratio (100 x [nitrite]/([nitrate] + [nitrite]); (ii) plasma nitrite, S-nitrosothiols and other nitroso species (RXNO); (iii) endothelial function (measured by flow mediated dilatation); (iv) BP; (v) neurocognitive performance; (vi) mood; and (vii) anxiety. RESULTS Consumption of the nitrate-rich meal resulted in a significant increase in markers of nitrate metabolism. A significantly higher peak flow mediated dilatation was observed with chewing compared to no chewing (baseline adjusted mean difference: 1.10%, 95% CI: 0.06, 2.14; p = 0.038) after the nitrate-rich meal. A significant small increase in systolic BP, diastolic BP and heart rate were observed with chewing compared to no chewing after the nitrate-rich meal. The study did not observe increased oral reduction of nitrate to nitrite and NO, or improvements in neurocognitive performance, mood or anxiety with chewing compared to no chewing. CONCLUSION Chewing gum after a nitrate-rich meal resulted in an acute improvement in endothelial function and a small increase in BP but did not result in acute effects on neurocognitive function, mood or anxiety.
Collapse
Affiliation(s)
- Sharon Ong
- Institute for Nutrition Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia
| | - Nicola P Bondonno
- Institute for Nutrition Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.,School of Biomedical Sciences, Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia, Australia
| | - Luke A Downey
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, Victoria, Australia.,Institute for Breathing & Sleep, Austin Hospital, Heidelberg, Victoria, Australia
| | - Andrew Scholey
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, Victoria, Australia
| | - Michael A Smith
- Department of Psychology, University of Northumbria, Newcastle, UK
| | - Con Stough
- Centre for Human Psychopharmacology, Swinburne University, Melbourne, Victoria, Australia
| | - Lauren C Blekkenhorst
- Institute for Nutrition Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.,Medical School, Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia, Australia
| | - Richard Woodman
- Flinders Centre for Epidemiology and Biostatistics, Flinders University, Adelaide, South Australia, Australia
| | - Kevin D Croft
- School of Biomedical Sciences, Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia, Australia
| | - Jonathan M Hodgson
- Institute for Nutrition Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.,Medical School, Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia, Australia
| | - Catherine P Bondonno
- Institute for Nutrition Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Western Australia, Australia.,Medical School, Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia, Australia
| |
Collapse
|
11
|
Ichwan M, Walker TL, Nicola Z, Ludwig-Müller J, Böttcher C, Overall RW, Adusumilli VS, Bulut M, Sykes AM, Hübner N, Ramirez-Rodriguez G, Ortiz-López L, Lugo-Hernández EA, Kempermann G. Apple Peel and Flesh Contain Pro-neurogenic Compounds. Stem Cell Reports 2021; 16:548-565. [PMID: 33577796 PMCID: PMC7940132 DOI: 10.1016/j.stemcr.2021.01.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 01/10/2021] [Accepted: 01/12/2021] [Indexed: 12/31/2022] Open
Abstract
As mammals evolved with exposure to particular diets, naturally abundant compounds may have become part of the set of environmental co-determinants that shaped brain structure and function. Here we investigated whether bioactive factors found in apples directly affect hippocampal neurogenesis in the adult mouse. We found that quercetin, the most abundant flavanol in apple peel, was anti-proliferative at high concentrations but pro-neurogenic at low concentrations. This was confirmed in vivo, with intraperitoneally delivered quercetin promoting survival and neuronal differentiation, without affecting proliferation. Using a bioassay-guided fractionation approach we also identified additional pro-neurogenic compounds in apple flesh that were not related to flavonoids. We found that 3,5-dihydroxybenzoic acid significantly increased neural precursor cell proliferation and neurogenesis. This work shows that both flavonoids and 3,5-dihydroxybenzoic acid are pro-neurogenic, not only by activating precursor cell proliferation but also by promoting cell-cycle exit, cellular survival, and neuronal differentiation.
Collapse
Affiliation(s)
- Muhammad Ichwan
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany; Department of Pharmacology and Therapeutics, Faculty of Medicine, Universitas Sumatera Utara, Medan, 20155, Indonesia
| | - Tara L Walker
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany; Queensland Brain Institute (QBI), The University of Queensland, Brisbane 4072, Australia
| | - Zeina Nicola
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany
| | - Jutta Ludwig-Müller
- Institute for Botany, Technische Universität Dresden, 01062 Dresden, Germany
| | | | - Rupert W Overall
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany
| | - Vijay S Adusumilli
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany
| | - Merve Bulut
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany
| | - Alex M Sykes
- Griffith Institute for Drug Discovery, Griffith University, Brisbane 4111, Australia
| | - Norbert Hübner
- Max-Delbrück-Centrum für Molekulare Medizin (MDC), 13125 Berlin, Germany
| | - Gerardo Ramirez-Rodriguez
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramon de laFuente Muñiz," Mexico DF, Mexico
| | - Leonardo Ortiz-López
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramon de laFuente Muñiz," Mexico DF, Mexico
| | - Enrique A Lugo-Hernández
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramon de laFuente Muñiz," Mexico DF, Mexico
| | - Gerd Kempermann
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, 01307 Dresden, Germany; German Center for Neurodegenerative Diseases (DZNE) Dresden, 01307 Dresden, Germany.
| |
Collapse
|
12
|
Ward-Ritacco CL, Wilson AR, O’Connor PJ. An Apple Extract Beverage Combined with Caffeine Can Improve Alertness, Mental Fatigue, and Information Processing Speed. JOURNAL OF COGNITIVE ENHANCEMENT 2021. [DOI: 10.1007/s41465-020-00204-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AbstractThe psychological effects of low-dose caffeine combined with polyphenols from apples have rarely been explored scientifically yet synergistic effects are plausible. A randomized, double-blind, placebo-controlled cross-over experiment was used to test the psychological effects of apple extract beverages combined with 10, 20, 37.5, and 75 mg caffeine. Comparisons were made to both a placebo drink that was artificially sweetened and colored to mimic the test beverages and a positive control drink with 75 mg caffeine but without apple extract. Compared to placebo, it was hypothesized that dose-dependent improvements in cognitive performance, mood, and motivation would be realized after consuming the beverage with apple extract containing added caffeine. Outcomes were assessed before, 60 to 110, and 125 to 175 min post-beverage. The positive control beverage resulted in more serial seven subtractions, greater motivation to perform cognitive tasks, and reduced feelings of fatigue (all p < .005). The study found that psychological effects (i) were not observed for beverages containing apple extract and 10 or 20 mg caffeine, (ii) of the apple extract beverage containing 75 mg caffeine generally mimicked the effects of the positive control drink and significantly increased serial seven processing speed, and (iii) of the apple extract beverage containing 37.5 mg improved feelings of alertness and mental fatigue. In sum, effects of apple extract combined with caffeine were not dose-dependent; the apple extract beverage containing 75 mg caffeine improved information processing speed and the apple extract beverage with 37.5 mg caffeine improved feelings of alertness and mental fatigue.
Collapse
|
13
|
Nitrate and nitrite exposure leads to mild anxiogenic-like behavior and alters brain metabolomic profile in zebrafish. PLoS One 2020; 15:e0240070. [PMID: 33382700 PMCID: PMC7774831 DOI: 10.1371/journal.pone.0240070] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 12/11/2020] [Indexed: 02/06/2023] Open
Abstract
Dietary nitrate lowers blood pressure and improves athletic performance in humans, yet data supporting observations that it may increase cerebral blood flow and improve cognitive performance are mixed. We tested the hypothesis that nitrate and nitrite treatment would improve indicators of learning and cognitive performance in a zebrafish (Danio rerio) model. We utilized targeted and untargeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis to examine the extent to which treatment resulted in changes in nitrate or nitrite concentrations in the brain and altered the brain metabolome. Fish were exposed to sodium nitrate (606.9 mg/L), sodium nitrite (19.5 mg/L), or control water for 2–4 weeks and free swim, startle response, and shuttle box assays were performed. Nitrate and nitrite treatment did not change fish weight, length, predator avoidance, or distance and velocity traveled in an unstressed environment. Nitrate- and nitrite-treated fish initially experienced more negative reinforcement and increased time to decision in the shuttle box assay, which is consistent with a decrease in associative learning or executive function however, over multiple trials, all treatment groups demonstrated behaviors associated with learning. Nitrate and nitrite treatment was associated with mild anxiogenic-like behavior but did not alter epinephrine, norepinephrine or dopamine levels. Targeted metabolomics analysis revealed no significant increase in brain nitrate or nitrite concentrations with treatment. Untargeted metabolomics analysis found 47 metabolites whose abundance was significantly altered in the brain with nitrate and nitrite treatment. Overall, the depletion in brain metabolites is plausibly associated with the regulation of neuronal activity including statistically significant reductions in the inhibitory neurotransmitter γ-aminobutyric acid (GABA; 18–19%), and its precursor, glutamine (17–22%). Nitrate treatment caused significant depletion in the brain concentration of fatty acids including linoleic acid (LA) by 50% and arachidonic acid (ARA) by 80%; nitrite treatment caused depletion of LA by ~90% and ARA by 60%, change which could alter the function of dopaminergic neurons and affect behavior. Nitrate and nitrite treatment did not adversely affect multiple parameters of zebrafish health. It is plausible that indirect NO-mediated mechanisms may be responsible for the nitrate and nitrite-mediated effects on the brain metabolome and behavior in zebrafish.
Collapse
|
14
|
Fisk J, Khalid S, Reynolds SA, Williams CM. Effect of 4 weeks daily wild blueberry supplementation on symptoms of depression in adolescents. Br J Nutr 2020; 124:181-188. [PMID: 32151287 DOI: 10.1017/s0007114520000926] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Adolescence is an important period for cognitive maturation and emotional regulation, and this age group is particularly vulnerable to developing depression. Diets rich in fruits and vegetables have been associated with decreased risk of developing depressive disorders across the lifespan, maybe due to the high flavonoid content of these foods. Previously, we have shown increases in transient positive affect (PA) in both children and young adults 2 h after administration of a wild blueberry (WBB) intervention. Here, using a randomised double-blind, placebo-controlled trial, we investigated the effects of 4 weeks, daily WBB supplementation (containing about 253 mg anthocyanins) on transient and chronic mood in adolescents. Healthy 12-17-year old (n 64, thirty-five females) participants were randomly assigned to receive either a WBB or matched placebo supplementation. Depression and anxiety symptoms were assessed before and after the intervention period using the Mood and Feeling Questionnaire and Revised Child Anxiety and Depression Scale. Transient affect was assessed before, 2 weeks and at 4 weeks using PA and negative affect. Following the intervention period, there were significantly fewer self-reported depression symptoms in participants who were supplemented with WBB compared with placebo (P = 0·02, 95 % CI -6·71, -5·35). There was no between-group effect on anxiety symptoms or on transient affect. Further investigation is required to identify specific mechanisms that link flavonoids consumption and mood. If replicated, the observed effects of WBB supplementation may be a potential prevention strategy for adolescent depression and may have benefits for public mental health.
Collapse
Affiliation(s)
- Jeni Fisk
- School of Psychology and Clinical Language Sciences, University of Reading, Reading, BerkshireRG6 6BZ, UK
| | - Sundus Khalid
- School of Psychology and Clinical Language Sciences, University of Reading, Reading, BerkshireRG6 6BZ, UK
| | - Shirley A Reynolds
- School of Psychology and Clinical Language Sciences, University of Reading, Reading, BerkshireRG6 6BZ, UK
| | - Claire M Williams
- School of Psychology and Clinical Language Sciences, University of Reading, Reading, BerkshireRG6 6BZ, UK
| |
Collapse
|
15
|
Kapil V, Khambata RS, Jones DA, Rathod K, Primus C, Massimo G, Fukuto JM, Ahluwalia A. The Noncanonical Pathway for In Vivo Nitric Oxide Generation: The Nitrate-Nitrite-Nitric Oxide Pathway. Pharmacol Rev 2020; 72:692-766. [DOI: 10.1124/pr.120.019240] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
|
16
|
Gabrial SGN, Shakib MCR, Haleem MSMA, Gabrial GN, El-Shobaki FA. Hypoglycemic Potential of Supplementation with a Vegetable and Legume Juice Formula in Type 2 Diabetic Patients. Pak J Biol Sci 2020; 23:132-138. [PMID: 31944072 DOI: 10.3923/pjbs.2020.132.138] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND OBJECTIVE Type 2 diabetes affects a large number of people all over the world; hence, it is worthy to supplement those patients with a food formula containing biologically active ingredients that can help to control the disease and its complications. The present study was designed to prepare a plant formula in the form of a juice taken during treatment to synergies and reduce the drug dose used and minimize disease complications. MATERIALS AND METHODS The formula is formed of spinach, broccoli, celery, green beans and chickpea. The total fat, fatty acids, polyphenol content and the antioxidant power of the formula were determined. The blood sugar tolerance curves of the volunteers were followed after breakfast alone, breakfast and treatment dose, also when this formula was given before breakfast. RESULTS The vegetable and legume juice could reduce postprandial glucose level when given before the breakfast and the effect was more or less similar to the effect of the treatment drug. The juice proved to contain some polyphenols and possess an antioxidant character. Analysis proved that it is rich in polyunsaturated fatty acids. CONCLUSION It is recommended to use this juice for diabetic patients to reduce hyperglycemia and synergize the effect of the used drug. It can thus avoid health problems that occur to those patients when using drugs for long time and in massive amounts.
Collapse
|
17
|
Gutierrez RMP, Velazquez EG, Carrera SPP. Spinacia oleracea Linn Considered as One of the Most Perfect Foods: A Pharmacological and Phytochemical Review. Mini Rev Med Chem 2019; 19:1666-1680. [PMID: 31161986 DOI: 10.2174/1389557519666190603090347] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 07/02/2018] [Accepted: 05/06/2019] [Indexed: 12/16/2022]
Abstract
Background: :
Leaves of Spinacia oleracea have been widely used as vegetarian foods.
Some studies on the chemical composition of spinach have shown that it contains a high content of micronutrients
(vitamins and minerals), and has an important economic value with some agronomic advantages.
S. oleracea in traditional medicine is reported to cure more than one health problem.
Objective: :
This review focuses on the ethnopharmacological uses and pharmacological and phytochemical
studies of Spinacia oleracea.
Method: :
Information on S. oleracea was obtained via electronic search of scientific databases such as
Scopus, PubMed, Google Scholar, Scirus, Science Direct, Scielo, Web of Science, Medline, Springerlink,
BioMed Central (BMC), and SciFinder for publications on this plant. In addition, books on medicinal
herbs were also consulted.
Results: :
Approximately 100 chemical compounds were isolated and characterized from S. oleracea.
The major active components of the plant are flavones, flavanols, methylenedioxyflavonol glucuronides,
glucuronides, and carotenoids, which were extensively investigated. This review revealed potential
pharmacological properties of these isolated compounds such as anti-obesity, anti-α-amylase, bileacid
binding capacity, anti-mutagenic, anti-oxidant, anticancer, anti-inflammatory, cognitive and mood
effect, hypoglycemic, and anti-hypertriglyceridemia.
Conclusions::
S. oleracea is an important edible plant also used for ethnomedical therapy of obesity, inflammation
of lungs, lumbago, flatulence, and treatment of urinary calculi. Pharmacological and phytochemical
studies of this plant including bioactives, which have been adequately studied, support its
uses in traditional medicine. Additionally, prospects and future trends of this plant are proposed.
Collapse
Affiliation(s)
- Rosa Martha Perez Gutierrez
- Laboratorio de Investigacion de Productos Naturales, Escuela Superior de Ingenieria Quimica e Industrias Extractivas, Instituto Politecnico Nacional (IPN) Unidad Profesional Adolfo Lopez Mateos S/N Av. Instituto Politecnico Nacional Ciudad de Mexico, cp 07708, Mexico
| | - Elisa Gutierrez Velazquez
- Laboratorio de Investigacion de Productos Naturales, Escuela Superior de Ingenieria Quimica e Industrias Extractivas, Instituto Politecnico Nacional (IPN) Unidad Profesional Adolfo Lopez Mateos S/N Av. Instituto Politecnico Nacional Ciudad de Mexico, cp 07708, Mexico
| | - Silvia Patricia Paredes Carrera
- Laboratorio de Nanomateriales Sustentables, Escuela Superior de Ingenieria Quimica e Industrias Extractivas, Instituto Politecnico Nacional (IPN) Unidad Profesional Adolfo Lopez Mateos S/N Av. Instituto Politecnico Nacional Ciudad de Mexico, cp. 07708, Mexico
| |
Collapse
|
18
|
Shannon OM, Grisotto G, Babateen A, McGrattan A, Brandt K, Mathers JC, Siervo M. Knowledge and beliefs about dietary inorganic nitrate among UK-based nutrition professionals: Development and application of the KINDS online questionnaire. BMJ Open 2019; 9:e030719. [PMID: 31676652 PMCID: PMC6830619 DOI: 10.1136/bmjopen-2019-030719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 07/29/2019] [Accepted: 09/06/2019] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVES To examine knowledge and beliefs about the biological roles of dietary inorganic nitrate in UK-based nutrition professionals, and to explore potential differences by participants' education level. SETTING An online questionnaire was administered to UK-based nutrition professionals, exploring knowledge and/or beliefs across five areas: (1) health and performance effects of nitrate; (2) current and recommended intake values for nitrate; (3) dietary sources of nitrate; (4) methods of evaluating nitrate intake and (5) nitrate metabolism. PARTICIPANTS One hundred and twenty-five nutrition professionals. PRIMARY OUTCOME Knowledge and beliefs about inorganic nitrate. RESULTS Most nutrition professionals taking part in the survey had previously heard of inorganic nitrate (71%) and perceived it to be primarily beneficial (51%). The majority believed that nitrate consumption can improve sports performance (59%) and reduce blood pressure (54%), but were unsure about effects on cognitive function (71%), kidney function (80%) and cancer risk (70%). Knowledge of dietary sources of nitrate and factors affecting its content in food were generally good (41%-79% of participants providing correct answers). However, most participants were unsure of the average population intake (65%) and the acceptable daily intake (64%) of nitrate. Most participants (65%) recognised at least one compound (ie, nitric oxide or nitrosamines) that is derived from dietary nitrate in the body. Knowledge of nitrate, quantified by a 23-point index created by summing correct responses, was greater in individuals with a PhD (p=0.01; median (IQR)=13 (9-17)) and tended to be better in respondents with a masters degree (p=0.054; 13 (8-15)) compared with undergraduate-level qualifications (10 (2-14)). CONCLUSIONS UK-based nutrition professionals demonstrated mixed knowledge about the physiology of dietary nitrate, which was better in participants with higher education. More efficient dissemination of current knowledge about inorganic nitrate and its effects on health to nutrition professionals will support them to make more informed recommendations about consumption of this compound.
Collapse
Affiliation(s)
- Oliver M Shannon
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Giorgia Grisotto
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Abrar Babateen
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Andrea McGrattan
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Kirsten Brandt
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - John C Mathers
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Mario Siervo
- Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
- School of Life Sciences, The University of Nottingham Medical School, University of Nottingham, Nottingham, UK
| |
Collapse
|
19
|
Fraga CG, Croft KD, Kennedy DO, Tomás-Barberán FA. The effects of polyphenols and other bioactives on human health. Food Funct 2019; 10:514-528. [PMID: 30746536 DOI: 10.1039/c8fo01997e] [Citation(s) in RCA: 533] [Impact Index Per Article: 106.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although deficiencies in polyphenol intake do not result in specific deficiency diseases, adequate intake of polyphenols could confer health benefits, especially with regard to chronic diseases. Tea, cocoa, fruits, and berries, as well as vegetables, are rich in polyphenols. Flavan-3-ols from cocoa have been found to be associated with a reduced risk of stroke, myocardial infarction, and diabetes, as well as improvements in lipids, endothelial-dependent blood flow and blood pressure, insulin resistance, and systemic inflammation. The flavonoid quercetin and the stilbene resveratrol have also been associated with cardiometabolic health. Although polyphenols have been associated with improved cerebral blood flow, evidence of an impact on cognition is more limited. The ability of dietary polyphenols to produce clinical effects may be due, at least in part, to a bi-directional relationship with the gut microbiota. Polyphenols can impact the composition of the gut microbiota (which are independently associated with health benefits), and gut bacteria metabolize polyphenols into bioactive compounds that produce clinical benefits. Another critical interaction is that of polyphenols with other phytochemicals, which could be relevant to interpreting the health parameter effects of polyphenols assayed as purified extracts, whole foods, or whole food extracts.
Collapse
Affiliation(s)
- César G Fraga
- Fisicoquímica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
| | | | | | | |
Collapse
|
20
|
Kennedy DO. Phytochemicals for Improving Aspects of Cognitive Function and Psychological State Potentially Relevant to Sports Performance. Sports Med 2019; 49:39-58. [PMID: 30671903 PMCID: PMC6445817 DOI: 10.1007/s40279-018-1007-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Subjective alertness and optimal cognitive function, including in terms of attention, spatial/working memory and executive function, are intrinsic to peak performance in many sports. Consumption of a number of plant-derived 'secondary metabolite' phytochemicals can modulate these psychological parameters, although there is a paucity of evidence collected in a sporting context. The structural groups into which these phytochemicals fall-phenolics, terpenes and alkaloids-vary in terms of the ecological roles they play for the plant, their toxicity and the extent to which they exert direct effects on brain function. The phenolics, including polyphenols, play protective roles in the plant, and represent a natural, benign component of the human diet. Increased consumption has been shown to improve cardiovascular function and is associated with long-term brain health. However, whilst short-term supplementation with polyphenols has been shown to consistently modulate cerebral blood-flow parameters, evidence of direct effects on cognitive function and alertness/arousal is currently comparatively weak. Terpenes play both attractant and deterrent roles in the plant, and typically occur less frequently in the diet. Single doses of volatile monoterpenes derived from edible herbs such as sage (Salvia officinalis/lavandulaefolia) and peppermint (Mentha piperita), diterpene-rich Ginkgo biloba extracts and triterpene-containing extracts from plants such as ginseng (Panax ginseng/quinquefolius) and Bacopa monnieri have all been shown to enhance relevant aspects of cognitive function and alertness. The alkaloids play toxic defensive roles in the plant, including via interference with herbivore brain function. Whilst most alkaloids are inappropriate in a sporting context due to toxicity and legal status, evidence suggests that single doses of nicotine and caffeine may be able to enhance relevant aspects of cognitive function and/or alertness. However, their benefits may be confounded by habituation and withdrawal effects in the longer term. The efficacy of volatile terpenes, triterpene-rich extracts and products combining low doses of caffeine with other phytochemicals deserves more research attention.
Collapse
Affiliation(s)
- David O Kennedy
- Brain, Performance and Nutrition Research Centre, Northumbria University, Newcastle-upon-Tyne, NE1 8ST, UK.
| |
Collapse
|
21
|
Kaur G, Thawkar B, Dubey S, Jadhav P. Pharmacological potentials of betalains. ACTA ACUST UNITED AC 2018; 15:/j/jcim.ahead-of-print/jcim-2017-0063/jcim-2017-0063.xml. [DOI: 10.1515/jcim-2017-0063] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 02/12/2018] [Indexed: 11/15/2022]
Abstract
Abstract
Betalains are water soluble plant pigments in plants of the order Caryophyllales, which are widely used as colorants. Several preclinical studies reported that betanin reveals antioxidants, anti-inflammatory, hepatoprotective, anticancer, anti-diabetes, anti-lipid emic, antimicrobial activity, radio protective and anti-proliferative activity. They are isolated from sources such as red beetroot, amaranth, prickly pear, red pitahaya, etc. Betalains are divided into two groups based on the colour and confer either the betacyanins (purple reddish) or betaxanthins (yellowish orange). Betalain is one of the promising nutraceuticals which can provide beneficial effects for prevention and cure of various diseases. The purpose of this review is to focus on nutraceutical facts of betalains by focusing on the ongoing treatment using betalains and to address its future nutraceuticals implications.
Collapse
|
22
|
Clifford T, Babateen A, Shannon OM, Capper T, Ashor A, Stephan B, Robinson L, O'Hara JP, Mathers JC, Stevenson E, Siervo M. Effects of inorganic nitrate and nitrite consumption on cognitive function and cerebral blood flow: A systematic review and meta-analysis of randomized clinical trials. Crit Rev Food Sci Nutr 2018; 59:2400-2410. [PMID: 29617153 DOI: 10.1080/10408398.2018.1453779] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We conducted a systematic review and meta-analysis of randomized clinical trials examining the effect of inorganic nitrate or nitrite supplementation on cognitive function (CF) and cerebral blood flow (CBF). Two databases (PubMed, Embase) were searched for articles from inception until May 2017. Inclusion criteria were: randomized clinical trials; participants >18 years old; trials comparing a nitrate/nitrite intervention with a control. Thirteen and nine trials were included in the meta-analysis to assess CF and CBF, respectively. Random-effects models were used and the effect size described as standardized mean differences (SMDs). A total of 297 participants (median of 23 per trial) were included for CF; 163 participants (median of 16 per trial) were included for CBF. Nitrate/nitrite supplementation did not influence CF (SMD +0.06, 95% CI: -0.06, 0.18, P = 0.32) or CBF under resting (SMD +0.14, 95% CI: -0.13, 0.41, P = 0.31), or stimulated conditions (SMD + 0.23, 95% CI: -0.11, 0.56, P = 0.19). The meta-regression showed an inverse association between duration of the intervention and CBF (P = 0.02) but no influence of age, BMI or dose (P < 0.05). Nitrate and nitrite supplementation did not modify CBF or CF. Further trials employing larger samples sizes and interventions with longer duration are warranted.
Collapse
Affiliation(s)
- Tom Clifford
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK
| | - Abrar Babateen
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK.,b Faculty of Applied Medical Sciences, Clinical Nutrition Department, Umm Al-Qura University , Makkah , Saudi Arabia
| | - Oliver M Shannon
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK.,c Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett University , Leeds , UK
| | - Tess Capper
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK
| | - Ammar Ashor
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK.,d College of Medicine, University of Al-Mustansiriyah , Baghdad , Iraq
| | - Blossom Stephan
- e Institute of Health and Society, Newcastle University , Newcastle upon Tyne , UK
| | - Louise Robinson
- e Institute of Health and Society, Newcastle University , Newcastle upon Tyne , UK
| | - John P O'Hara
- c Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett University , Leeds , UK
| | - John C Mathers
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK
| | - Emma Stevenson
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK
| | - Mario Siervo
- a Human Nutrition Research Centre, Institute of Cellular Medicine, Newcastle University , Newcastle on Tyne , UK
| |
Collapse
|
23
|
Shannon OM, Duckworth L, Barlow MJ, Deighton K, Matu J, Williams EL, Woods D, Xie L, Stephan BCM, Siervo M, O'Hara JP. Effects of Dietary Nitrate Supplementation on Physiological Responses, Cognitive Function, and Exercise Performance at Moderate and Very-High Simulated Altitude. Front Physiol 2017. [PMID: 28649204 PMCID: PMC5465306 DOI: 10.3389/fphys.2017.00401] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose: Nitric oxide (NO) bioavailability is reduced during acute altitude exposure, contributing toward the decline in physiological and cognitive function in this environment. This study evaluated the effects of nitrate (NO3−) supplementation on NO bioavailability, physiological and cognitive function, and exercise performance at moderate and very-high simulated altitude. Methods:Ten males (mean (SD): V˙O2max: 60.9 (10.1) ml·kg−1·min−1) rested and performed exercise twice at moderate (~14.0% O2; ~3,000 m) and twice at very-high (~11.7% O2; ~4,300 m) simulated altitude. Participants ingested either 140 ml concentrated NO3−-rich (BRJ; ~12.5 mmol NO3−) or NO3−-deplete (PLA; 0.01 mmol NO3−) beetroot juice 2 h before each trial. Participants rested for 45 min in normobaric hypoxia prior to completing an exercise task. Exercise comprised a 45 min walk at 30% V˙O2max and a 3 km time-trial (TT), both conducted on a treadmill at a 10% gradient whilst carrying a 10 kg backpack to simulate altitude hiking. Plasma nitrite concentration ([NO2−]), peripheral oxygen saturation (SpO2), pulmonary oxygen uptake (V˙O2), muscle and cerebral oxygenation, and cognitive function were measured throughout. Results: Pre-exercise plasma [NO2−] was significantly elevated in BRJ compared with PLA (p = 0.001). Pulmonary V˙O2 was reduced (p = 0.020), and SpO2 was elevated (p = 0.005) during steady-state exercise in BRJ compared with PLA, with similar effects at both altitudes. BRJ supplementation enhanced 3 km TT performance relative to PLA by 3.8% [1,653.9 (261.3) vs. 1718.7 (213.0) s] and 4.2% [1,809.8 (262.0) vs. 1,889.1 (203.9) s] at 3,000 and 4,300 m, respectively (p = 0.019). Oxygenation of the gastrocnemius was elevated during the TT consequent to BRJ (p = 0.011). The number of false alarms during the Rapid Visual Information Processing Task tended to be lower with BRJ compared with PLA prior to altitude exposure (p = 0.056). Performance in all other cognitive tasks did not differ significantly between BRJ and PLA at any measurement point (p ≥ 0.141). Conclusion: This study suggests that BRJ improves physiological function and exercise performance, but not cognitive function, at simulated moderate and very-high altitude.
Collapse
Affiliation(s)
- Oliver M Shannon
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| | - Lauren Duckworth
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| | - Matthew J Barlow
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| | - Kevin Deighton
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| | - Jamie Matu
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| | - Emily L Williams
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| | - David Woods
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom.,Defence Medical Services, Royal Centre for Defence MedicineBirmingham, United Kingdom
| | - Long Xie
- Institute for Ageing and Health, Newcastle UniversityNewcastle upon Tyne, United Kingdom
| | - Blossom C M Stephan
- Institute for Ageing and Health, Newcastle UniversityNewcastle upon Tyne, United Kingdom
| | - Mario Siervo
- Institute for Ageing and Health, Newcastle UniversityNewcastle upon Tyne, United Kingdom
| | - John P O'Hara
- Research Institute for Sport, Physical Activity, and Leisure, Leeds Beckett UniversityLeeds, United Kingdom
| |
Collapse
|
24
|
Dietz C, Dekker M, Piqueras-Fiszman B. An intervention study on the effect of matcha tea, in drink and snack bar formats, on mood and cognitive performance. Food Res Int 2017; 99:72-83. [PMID: 28784536 DOI: 10.1016/j.foodres.2017.05.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 03/16/2017] [Accepted: 05/04/2017] [Indexed: 12/16/2022]
Abstract
Matcha tea is gaining popularity throughout the world in recent years and is frequently referred to as a mood-and-brain food. Previous research has demonstrated that three constituents present in matcha tea, l-theanine, epigallocatechin gallate (EGCG), and caffeine, affect mood and cognitive performance. However, to date there are no studies assessing the effect of matcha tea itself. The present study investigates these effects by means of a human intervention study administering matcha tea and a matcha containing product. Using a randomized, placebo-controlled, single-blind study, 23 consumers participated in four test sessions. In each session, participants consumed one of the four test products: matcha tea, matcha tea bar (each containing 4g matcha tea powder), placebo tea, or placebo bar. The assessment was performed at baseline and 60min post-treatment. The participants performed a set of cognitive tests assessing attention, information processing, working memory, and episodic memory. The mood state was measured by means of a Profile of Mood States (POMS). After consuming the matcha products compared to placebo versions, there were mainly significant improvements in tasks measuring basic attention abilities and psychomotor speed in response to stimuli over a defined period of time. In contrast to expectations, the effect was barely present in the other cognitive tasks. The POMS results revealed no significant changes in mood. The influence of the food matrix was demonstrated by the fact that on most cognitive performance measures the drink format outperformed the bar format, particularly in tasks measuring speed of spatial working memory and delayed picture recognition. This study suggests that matcha tea consumed in a realistic dose can induce slight effects on speed of attention and episodic secondary memory to a low degree. Further studies are required to elucidate the influences of the food matrix.
Collapse
Affiliation(s)
- Christina Dietz
- Food Quality and Design Group, Wageningen University, The Netherlands
| | - Matthijs Dekker
- Food Quality and Design Group, Wageningen University, The Netherlands
| | | |
Collapse
|
25
|
Effects of Acute Blueberry Flavonoids on Mood in Children and Young Adults. Nutrients 2017; 9:nu9020158. [PMID: 28230732 PMCID: PMC5331589 DOI: 10.3390/nu9020158] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 01/31/2017] [Accepted: 02/07/2017] [Indexed: 11/25/2022] Open
Abstract
Epidemiological evidence suggests that consumption of flavonoids (usually via fruits and vegetables) is associated with decreased risk of developing depression. One plausible explanation for this association is the well-documented beneficial effects of flavonoids on executive function (EF). Impaired EF is linked to cognitive processes (e.g., rumination) that maintain depression and low mood; therefore, improved EF may reduce depressionogenic cognitive processes and improve mood. Study 1: 21 young adults (18–21 years old) consumed a flavonoid-rich blueberry drink and a matched placebo in a counterbalanced cross-over design. Study 2: 50 children (7–10 years old) were randomly assigned to a flavonoid-rich blueberry drink or a matched placebo. In both studies, participants and researchers were blind to the experimental condition, and mood was assessed using the Positive and Negative Affect Schedule before and 2 h after consumption of the drinks. In both studies, the blueberry intervention increased positive affect (significant drink by session interaction) but had no effect on negative affect. This observed effect of flavonoids on positive affect in two independent samples is of potential practical value in improving public health. If the effect of flavonoids on positive affect is replicated, further investigation will be needed to identify the mechanisms that link flavonoid interventions with improved positive mood.
Collapse
|
26
|
Jiang X, Huang J, Song D, Deng R, Wei J, Zhang Z. Increased Consumption of Fruit and Vegetables Is Related to a Reduced Risk of Cognitive Impairment and Dementia: Meta-Analysis. Front Aging Neurosci 2017; 9:18. [PMID: 28223933 PMCID: PMC5293796 DOI: 10.3389/fnagi.2017.00018] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/23/2017] [Indexed: 01/07/2023] Open
Abstract
Background: Increased consumption of fruit and vegetables has been shown to be associated with a reduced risk of cognitive impairment and dementia in many epidemiological studies. The purpose of this study was to assess the strength of this association in a meta-analysis. Methods: We identified relevant studies by searching Medline, Embase, and Cochrane Library electronic databases (from 1970 to January 2016). Study were included if they reported relative risks and corresponding 95% confidence intervals (CIs) of cognitive impairment and dementia with respect to frequency of fruit and vegetable intake. Results: Nine studies (five cohort studies and four cross-sectional studies) met the inclusion criteria and were included in the meta-analysis. There were a total of 31,104 participants and 4,583 incident cases of cognitive impairment and dementia. The meta-analysis showed that an increased consumption of fruit and vegetables was associated with a significant reduction in the risk of cognitive impairment and dementia (OR = 0.80, 95% CI 0.71–0.89). Subgroup analysis indicated this inverse association was only found among participants with mean age over 65 years and combined sexes. Dose–response meta-analysis showed that an increment of 100 g per day of fruit and vegetable consumption was related to an approximately 13% (OR = 0.87, 95% CI 0.77–0.99) reduction in cognitive impairment and dementia risk. There was no potential publication bias in the meta-analysis and the dose–response meta-analysis. Conclusion: The increased consumption of fruit and vegetables is associated with a reduced risk of cognitive impairment and dementia.
Collapse
Affiliation(s)
- Xian Jiang
- Department of Anesthesia, The Affiliated Hospital of Southwest Medical University Luzhou, China
| | - Jiang Huang
- Department of Pharmacy, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University Luzhou, China
| | - Daqiang Song
- Department of Pharmacology, School of Pharmacy of Southwest Medical University Luzhou, China
| | - Ru Deng
- Department of Anesthesia, The Affiliated Hospital of Southwest Medical University Luzhou, China
| | - Jicheng Wei
- Department of Anesthesia, The Affiliated Hospital of Southwest Medical University Luzhou, China
| | - Zhuo Zhang
- Department of Pharmacology, School of Pharmacy of Southwest Medical University Luzhou, China
| |
Collapse
|
27
|
The effects of flavanone-rich citrus juice on cognitive function and cerebral blood flow: an acute, randomised, placebo-controlled cross-over trial in healthy, young adults. Br J Nutr 2017; 116:2160-2168. [DOI: 10.1017/s000711451600430x] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
AbstractA plausible mechanism underlying flavonoid-associated cognitive effects is increased cerebral blood flow (CBF). However, behavioural and CBF effects following flavanone-rich juice consumption have not been explored. The aim of this study was to investigate whether consumption of flavanone-rich juice is associated with acute cognitive benefits and increased regional CBF in healthy, young adults. An acute, single-blind, randomised, cross-over design was applied with two 500-ml drink conditions – high-flavanone (HF; 70·5 mg) drink and an energy-, and vitamin C- matched, zero-flavanone control. A total of twenty-four healthy young adults aged 18–30 years underwent cognitive testing at baseline and 2-h after drink consumption. A further sixteen, healthy, young adults were recruited for functional MRI assessment, whereby CBF was measured with arterial spin labelling during conscious resting state at baseline as well as 2 and 5 h after drink consumption. The HF drink was associated with significantly increased regional perfusion in the inferior and middle right frontal gyrus at 2 h relative to baseline and the control drink. In addition, the HF drink was associated with significantly improved performance on the Digit Symbol Substitution Test at 2 h relative to baseline and the control drink, but no effects were observed on any other behavioural cognitive tests. These results demonstrate that consumption of flavanone-rich citrus juice in quantities commonly consumed can acutely enhance blood flow to the brain in healthy, young adults. However, further studies are required to establish a direct causal link between increased CBF and enhanced behavioural outcomes following citrus juice ingestion.
Collapse
|
28
|
Role of fruits, nuts, and vegetables in maintaining cognitive health. Exp Gerontol 2016; 94:24-28. [PMID: 28011241 DOI: 10.1016/j.exger.2016.12.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/14/2016] [Accepted: 12/16/2016] [Indexed: 12/11/2022]
Abstract
Population aging is leading to an increase in the incidence of age-related cognitive dysfunction and, with it, the health care burden of caring for older adults. Epidemiological studies have shown that consumption of fruits, nuts, and vegetables is positively associated with cognitive ability; however, these foods, which contain a variety of neuroprotective phytochemicals, are widely under-consumed. Surprisingly few studies have investigated the effects of individual plant foods on cognitive health but recent clinical trials have shown that dietary supplementation with individual foods, or switching to a diet rich in several of these foods, can improve cognitive ability. While additional research is needed, increasing fruit, nut, and vegetable intake may be an effective strategy to prevent or delay the onset of cognitive dysfunction during aging.
Collapse
|
29
|
Kent K, Charlton KE, Netzel M, Fanning K. Food-based anthocyanin intake and cognitive outcomes in human intervention trials: a systematic review. J Hum Nutr Diet 2016; 30:260-274. [PMID: 27730693 DOI: 10.1111/jhn.12431] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Preclinical evidence suggests that the anthocyanins, which comprise a subclass of dietary flavonoids providing the purple and red pigmentation in plant-based foods, may have a beneficial impact on cognitive outcomes. METHODS A systematic review was conducted to identify the published literature on food-based anthocyanin consumption and cognitive outcomes in human intervention trials. The literature search followed PRISMA guidelines and included six databases, as well as additional hand searching. RESULTS Seven studies were included in this review, comprising acute trials (n = 4) and longer-term (n = 3) interventions that assessed multiple cognitive outcomes in children, adults and older adults with cognitive impairment. Six of seven studies reported improvements in either a single, or multiple, cognitive outcomes, including verbal learning and memory, after anthocyanin-rich food consumption. As a result of methodological limitations and the large clinical and methodological diversity of the studies, the pooling of data for quantitative analysis was not feasible. CONCLUSIONS The impact of food-based anthocyanin consumption on both acute and long-term cognition appears promising. However, adequately powered studies that include sensitive cognitive tasks are needed to confirm these findings and allow the translation of research into dietary messages.
Collapse
Affiliation(s)
- K Kent
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - K E Charlton
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - M Netzel
- Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD, Australia
| | - K Fanning
- Department of Agriculture and Fisheries, Queensland Government, Brisbane, QLD, Australia
| |
Collapse
|
30
|
Sun Q, Wang D, Li FF, Yao GD, Li X, Li LZ, Huang XX, Song SJ. Cytotoxic prenylated flavones from the stem and root bark of Daphne giraldii. Bioorg Med Chem Lett 2016; 26:3968-72. [DOI: 10.1016/j.bmcl.2016.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 06/23/2016] [Accepted: 07/01/2016] [Indexed: 02/01/2023]
|
31
|
|
32
|
Morina F, Takahama U, Mojović M, Popović-Bijelić A, Veljović-Jovanović S. Formation of stable radicals in catechin/nitrous acid systems: Participation of dinitrosocatechin. Food Chem 2016; 194:1116-22. [DOI: 10.1016/j.foodchem.2015.08.081] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 07/27/2015] [Accepted: 08/20/2015] [Indexed: 12/27/2022]
|
33
|
Bell L, Lamport DJ, Butler LT, Williams CM. A Review of the Cognitive Effects Observed in Humans Following Acute Supplementation with Flavonoids, and Their Associated Mechanisms of Action. Nutrients 2015; 7:10290-306. [PMID: 26690214 PMCID: PMC4690090 DOI: 10.3390/nu7125538] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/13/2015] [Accepted: 12/01/2015] [Indexed: 12/18/2022] Open
Abstract
Flavonoids are polyphenolic compounds found in varying concentrations in many plant-based foods. Recent studies suggest that flavonoids can be beneficial to both cognitive and physiological health. Long term flavonoid supplementation over a period of weeks or months has been extensively investigated and reviewed, particularly with respect to cognitive ageing and neurodegenerative disease. Significantly less focus has been directed towards the short term effects of single doses of flavonoids on cognition. Here, we review 21 such studies with particular emphasis on the subclass and dose of flavonoids administered, the cognitive domains affected by flavonoid supplementation, and the effect size of the response. The emerging evidence suggests that flavonoids may be beneficial to attention, working memory, and psychomotor processing speed in a general population. Episodic memory effects are less well defined and may be restricted to child or older adult populations. The evidence also points towards a dose-dependent effect of flavonoids, but the physiological mechanisms of action remain unclear. Overall, there is encouraging evidence that flavonoid supplementation can benefit cognitive outcomes within an acute time frame of 0–6 h. But larger studies, combining cognitive and physiological measures, are needed to strengthen the evidence base.
Collapse
Affiliation(s)
- Lynne Bell
- School of Psychology and Clinical Language Sciences, University of Reading, Earley Gate, Whiteknights, Reading RG6 6AL, UK.
| | - Daniel J Lamport
- School of Psychology and Clinical Language Sciences, University of Reading, Earley Gate, Whiteknights, Reading RG6 6AL, UK.
| | - Laurie T Butler
- School of Psychology and Clinical Language Sciences, University of Reading, Earley Gate, Whiteknights, Reading RG6 6AL, UK.
| | - Claire M Williams
- School of Psychology and Clinical Language Sciences, University of Reading, Earley Gate, Whiteknights, Reading RG6 6AL, UK.
| |
Collapse
|
34
|
Kent K, Charlton K, Roodenrys S, Batterham M, Potter J, Traynor V, Gilbert H, Morgan O, Richards R. Consumption of anthocyanin-rich cherry juice for 12 weeks improves memory and cognition in older adults with mild-to-moderate dementia. Eur J Nutr 2015; 56:333-341. [PMID: 26482148 DOI: 10.1007/s00394-015-1083-y] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 10/09/2015] [Indexed: 02/01/2023]
Abstract
PURPOSE Dietary flavonoids, including anthocyanins, may positively influence cognition and may be beneficial for the prevention and treatment of dementia. We aimed to assess whether daily consumption of anthocyanin-rich cherry juice changed cognitive function in older adults with dementia. Blood pressure and anti-inflammatory effects were examined as secondary outcomes. METHODS A 12-week randomised controlled trial assessed cognitive outcomes in older adults (+70 year) with mild-to-moderate dementia (n = 49) after consumption of 200 ml/day of either a cherry juice or a control juice with negligible anthocyanin content. Blood pressure and inflammatory markers (CRP and IL-6) were measured at 6 and 12 weeks. ANCOVA controlling for baseline and RMANOVA assessed change in cognition and blood pressure. RESULTS Improvements in verbal fluency (p = 0.014), short-term memory (p = 0.014) and long-term memory (p ≤ 0.001) were found in the cherry juice group. A significant reduction in systolic (p = 0.038) blood pressure and a trend for diastolic (p = 0.160) blood pressure reduction was evident in the intervention group. Markers of inflammation (CRP and IL-6) were not altered. CONCLUSION Inclusion of an anthocyanin-rich beverage may be a practical and feasible way to improve total anthocyanin consumption in older adults with mild-to-moderate dementia, with potential to improve specific cognitive outcomes.
Collapse
Affiliation(s)
- Katherine Kent
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, 2522, Australia.
| | - Karen Charlton
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Steven Roodenrys
- School of Psychology, Faculty of Social Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Marijka Batterham
- Statistical Consulting Service, University of Wollongong, Wollongong, NSW, Australia
| | - Jan Potter
- Division of Aged Care and Rehabilitation, Illawarra Shoalhaven Local Health District, Wollongong Hospital, Wollongong, NSW, Australia
| | - Victoria Traynor
- School of Nursing, Faculty of Science, Medicine and Health, University of Wollongong, Wollongong, NSW, Australia
| | - Hayley Gilbert
- School of Psychology, Faculty of Social Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Olivia Morgan
- School of Psychology, Faculty of Social Sciences, University of Wollongong, Wollongong, NSW, Australia
| | - Rachelle Richards
- School of Psychology, Faculty of Social Sciences, University of Wollongong, Wollongong, NSW, Australia
| |
Collapse
|
35
|
Wightman EL, Haskell-Ramsay CF, Thompson KG, Blackwell JR, Winyard PG, Forster J, Jones AM, Kennedy DO. Dietary nitrate modulates cerebral blood flow parameters and cognitive performance in humans: A double-blind, placebo-controlled, crossover investigation. Physiol Behav 2015; 149:149-58. [PMID: 26037632 DOI: 10.1016/j.physbeh.2015.05.035] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/20/2015] [Accepted: 05/29/2015] [Indexed: 01/18/2023]
Abstract
Nitrate derived from vegetables is consumed as part of a normal diet and is reduced endogenously via nitrite to nitric oxide. It has been shown to improve endothelial function, reduce blood pressure and the oxygen cost of sub-maximal exercise, and increase regional perfusion in the brain. The current study assessed the effects of dietary nitrate on cognitive performance and prefrontal cortex cerebral blood-flow (CBF) parameters in healthy adults. In this randomised, double-blind, placebo-controlled, parallel-groups study, 40 healthy adults received either placebo or 450 ml beetroot juice (~5.5 mmol nitrate). Following a 90 minute drink/absorption period, participants performed a selection of cognitive tasks that activate the frontal cortex for 54 min. Near-Infrared Spectroscopy (NIRS) was used to monitor CBF and hemodynamics, as indexed by concentration changes in oxygenated and deoxygenated-haemoglobin, in the frontal cortex throughout. The bioconversion of nitrate to nitrite was confirmed in plasma by ozone-based chemi-luminescence. Dietary nitrate modulated the hemodynamic response to task performance, with an initial increase in CBF at the start of the task period, followed by consistent reductions during the least demanding of the three tasks utilised. Cognitive performance was improved on the serial 3s subtraction task. These results show that single doses of dietary nitrate can modulate the CBF response to task performance and potentially improve cognitive performance, and suggest one possible mechanism by which vegetable consumption may have beneficial effects on brain function.
Collapse
Affiliation(s)
- Emma L Wightman
- Brain, Performance and Nutrition Research Centre, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Crystal F Haskell-Ramsay
- Brain, Performance and Nutrition Research Centre, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Kevin G Thompson
- Sport, Exercise and Wellbeing Research Centre, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Jamie R Blackwell
- School of Sport and Health Sciences, St. Luke's Campus, University of Exeter, Exeter EX1 2LU, United Kingdom
| | - Paul G Winyard
- Peninsula College of Medicine and Dentistry, St. Luke's Campus, University of Exeter, Exeter EX1 2LU, United Kingdom
| | - Joanne Forster
- Brain, Performance and Nutrition Research Centre, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom
| | - Andrew M Jones
- School of Sport and Health Sciences, St. Luke's Campus, University of Exeter, Exeter EX1 2LU, United Kingdom
| | - David O Kennedy
- Brain, Performance and Nutrition Research Centre, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom.
| |
Collapse
|
36
|
The potential benefits of red beetroot supplementation in health and disease. Nutrients 2015; 7:2801-22. [PMID: 25875121 PMCID: PMC4425174 DOI: 10.3390/nu7042801] [Citation(s) in RCA: 229] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 03/17/2015] [Accepted: 04/09/2015] [Indexed: 12/15/2022] Open
Abstract
In recent years there has been a growing interest in the biological activity of red beetroot (Beta vulgaris rubra) and its potential utility as a health promoting and disease preventing functional food. As a source of nitrate, beetroot ingestion provides a natural means of increasing in vivo nitric oxide (NO) availability and has emerged as a potential strategy to prevent and manage pathologies associated with diminished NO bioavailability, notably hypertension and endothelial function. Beetroot is also being considered as a promising therapeutic treatment in a range of clinical pathologies associated with oxidative stress and inflammation. Its constituents, most notably the betalain pigments, display potent antioxidant, anti-inflammatory and chemo-preventive activity in vitro and in vivo. The purpose of this review is to discuss beetroot’s biological activity and to evaluate evidence from studies that specifically investigated the effect of beetroot supplementation on inflammation, oxidative stress, cognition and endothelial function.
Collapse
|
37
|
Short-term effects of a high nitrate diet on nitrate metabolism in healthy individuals. Nutrients 2015; 7:1906-15. [PMID: 25774606 PMCID: PMC4377889 DOI: 10.3390/nu7031906] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/19/2015] [Accepted: 02/28/2015] [Indexed: 11/17/2022] Open
Abstract
Dietary nitrate, through the enterosalivary nitrate-nitrite-NO pathway, can improve blood pressure and arterial stiffness. How long systemic nitrate and nitrite remain elevated following cessation of high nitrate intake is unknown. In 19 healthy men and women, the time for salivary and plasma nitrate and nitrite to return to baseline after 7 days increased nitrate intake from green leafy vegetables was determined. Salivary and plasma nitrate and nitrite was measured at baseline [D0], end of high nitrate diet [D7], day 9 [+2D], day 14 [+7D] and day 21 [+14D]. Urinary nitrite and nitrate was assessed at D7 and +14D. Increased dietary nitrate for 7 days resulted in a more than fourfold increase in saliva and plasma nitrate and nitrite (p < 0.001) measured at [D7]. At [+2D] plasma nitrite and nitrate had returned to baseline while saliva nitrate and nitrite were more than 1.5 times higher than at baseline levels. By [+7D] all metabolites had returned to baseline levels. The pattern of response was similar between men and women. Urinary nitrate and nitrate was sevenfold higher at D7 compared to +14D. These results suggest that daily ingestion of nitrate may be required to maintain the physiological changes associated with high nitrate intake.
Collapse
|
38
|
Morina F, Takahama U, Yamauchi R, Hirota S, Veljovic-Jovanovic S. Quercetin 7-O-glucoside suppresses nitrite-induced formation of dinitrosocatechins and their quinones in catechin/nitrite systems under stomach simulating conditions. Food Funct 2015; 6:219-29. [DOI: 10.1039/c4fo00695j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Catechins in foods can be transformed into dinitrosocatechins and the quinones by salivary nitrite in the stomach, and the transformation can be suppressed by flavonols including quercetin and its 7-O-glucoside.
Collapse
Affiliation(s)
- Filis Morina
- Institute for Multidisciplinary Research
- University of Belgrade
- Belgrade 11030
- Republic of Serbia
| | - Umeo Takahama
- Department of Bioscience
- Kyushu Dental University
- Kitakyushu 803-8580
- Japan
| | - Ryo Yamauchi
- Department of Applied Life Science
- Faculty of Applied Biological Sciences
- Gifu University
- Gifu 501-1193
- Japan
| | - Sachiko Hirota
- Faculty of Applied Health Sciences
- University of East Asia
- Shimonoseki 751-8503
- Japan
| | | |
Collapse
|
39
|
The effect of flavanol-rich cocoa on cerebral perfusion in healthy older adults during conscious resting state: a placebo controlled, crossover, acute trial. Psychopharmacology (Berl) 2015; 232:3227-34. [PMID: 26047963 PMCID: PMC4534492 DOI: 10.1007/s00213-015-3972-4] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 05/20/2015] [Indexed: 12/16/2022]
Abstract
RATIONALE There has recently been increasing interest in the potential of flavanols, plant-derived compounds found in foods such as fruit and vegetables, to ameliorate age-related cognitive decline. Research suggests that cocoa flavanols improve memory and learning, possibly as a result of their anti-inflammatory and neuroprotective effects. These effects may be mediated by increased cerebral blood flow (CBF), thus, stimulating neuronal function. OBJECTIVES The present study employed arterial spin labelling functional magnetic resonance imaging to explore the effect of a single acute dose of cocoa flavanols on regional CBF. METHODS CBF was measured pre- and post-consumption of low (23 mg) or high (494 mg) 330 ml equicaloric flavanol drinks matched for caffeine, theobromine, taste and appearance according to a randomized counterbalanced crossover double-blind design in eight males and ten females, aged 50-65 years. Changes in perfusion from pre- to post-consumption were calculated as a function of each drink. RESULTS Significant increases in regional perfusion across the brain were observed following consumption of the high flavanol drink relative to the low flavanol drink, particularly in the anterior cingulate cortex and the central opercular cortex of the parietal lobe. CONCLUSIONS Consumption of cocoa flavanol improves regional cerebral perfusion in older adults. This provides evidence for a possible acute mechanism by which cocoa flavanols are associated with benefits for cognitive performance.
Collapse
|
40
|
Wang JY, Zhu C, Qian TW, Guo H, Wang DD, Zhang F, Yin X. Extracts of black bean peel and pomegranate peel ameliorate oxidative stress-induced hyperglycemia in mice. Exp Ther Med 2014; 9:43-48. [PMID: 25452774 PMCID: PMC4247323 DOI: 10.3892/etm.2014.2040] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 09/24/2014] [Indexed: 12/18/2022] Open
Abstract
Oxidative stress has a central role in the progression of diabetes mellitus (DM), which can directly result in the injury of islet β cells and consequent hyperglycemia. The aim of the present study was to evaluate the possible protective effects of black bean peel extract (BBPE), pomegranate peel extract (PPE) and a combination of the two (PPE + BBPE) on streptozotocin-induced DM mice. Oxidative stress was assessed by the levels of total antioxidative capability and glutathione in the serum. Fasting blood glucose and insulin levels, as well as the pancreas weight index and the histological changes in the pancreas, were also determined. The results showed that, after fours weeks of treatment with PPE, BBPE or PPE + BBPE, DM mice showed, to different degrees, a decrease in blood glucose, increases in insulin secretion and the pancreas weight index, and an increase in antioxidative activity. These changes were particularly evident in the DM mice subjected to the combined intervention strategy of PPE + BBPE. The histological findings indicated that the injury to the pancreatic islets in DM mice was also ameliorated following treatment. In conclusion, PPE and BBPE, particularly the combination of the two, have the ability to ameliorate hyperglycemia by inhibiting oxidative stress-induced pancreatic damage; this finding may be useful in the prevention and treatment of DM.
Collapse
Affiliation(s)
- Jian-Yun Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Chuang Zhu
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Tian-Wei Qian
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Hao Guo
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Dong-Dong Wang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Fan Zhang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Xiaoxing Yin
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| |
Collapse
|