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PloS One 2024To systematically evaluate the safety and efficacy of antioxidant therapy in children and adolescents with attention deficit hyperactivity disorder (ADHD). (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To systematically evaluate the safety and efficacy of antioxidant therapy in children and adolescents with attention deficit hyperactivity disorder (ADHD).
METHODS
Randomized controlled trials and prospective studies on antioxidant therapy in children and adolescents with ADHD were searched in PubMed, Embase, and Cochrane Library from the inception of databases to November 12, 2022. Two investigators independently screened the literature, extracted data, and evaluated the quality of the included studies. Network meta-analysis (PROSPERO registration number CRD 42023382824) was carried out by using R Studio 4.2.1.
RESULTS
48 studies involving 12 antioxidant drugs (resveratrol, pycnogenol, omega-3, omega-6, quercetin, phosphatidylserine, almond, vitamin D, zinc, folic acid, ginkgo biloba, Acetyl-L-carnitine) were finally included, with 3,650 patients. Network meta-analysis showed that omega-6 (0.18), vitamin D (0.19), and quercetin (0.24) were the top three safest drugs according to SUCRA. The omega-3 (SUCRA 0.35), pycnogenol (SUCRA 0.36), and vitamin D (SUCRA 0.27) were the most effective in improving attention, hyperactivity, and total score of Conners' parent rating scale (CPRS), respectively. In terms of improving attention, hyperactivity, and total score of Conners' teacher rating scale (CTRS), pycnogenol (SUCRA 0.32), phosphatidylserine+omega-3 (SUCRA 0.26), and zinc (SUCRA 0.34) were the most effective, respectively. In terms of improving attention, hyperactivity and total score of ADHD Rating Scale-Parent, the optimal agents were phosphatidylserine (SUCRA 0.39), resveratrol+MPH (SUCRA 0.24), and phosphatidylserine (SUCRA 0.34), respectively. In terms of improving attention, hyperactivity and total score of ADHD Rating Scale-Teacher, pycnogenol (SUCRA 0.32), vitamin D (SUCRA 0.31) and vitamin D (SUCRA 0.18) were the optimal agents, respectively. The response rate of omega-3+6 was the highest in CGI (SUCRA 0.95) and CPT (SUCRA 0.42).
CONCLUSION
The rankings of safety and efficacy of the 12 antioxidants vary. Due to the low methodological quality of the included studies, the probability ranking cannot fully explain the clinical efficacy, and the results need to be interpreted with caution. More high-quality studies are still needed to verify our findings.
Topics: Child; Humans; Adolescent; Attention Deficit Disorder with Hyperactivity; Antioxidants; Network Meta-Analysis; Resveratrol; Quercetin; Prospective Studies; Phosphatidylserines; Fatty Acids, Omega-3; Vitamin D; Zinc
PubMed: 38547138
DOI: 10.1371/journal.pone.0296926 -
Journal of Clinical Medicine May 2020Affecting older and even some younger adults, neurodegenerative disease represents a global public health concern and has been identified as a research priority. To... (Review)
Review
CONTEXT
Affecting older and even some younger adults, neurodegenerative disease represents a global public health concern and has been identified as a research priority. To date, most anti-aging interventions have examined older adults, but little is known about the effects of polyphenol interventions on brain-related aging processes in healthy young and middle-aged adults.
OBJECTIVE
This systematic review and meta-analysis aimed to evaluate the acute and chronic effects of (poly)phenol-rich diet supplementation on cognitive function and brain health in young and middle-aged adults. In July 2019, two electronic databases (PubMed and Web of Science) were used to search for relevant trials examining the effect of acute or chronic (poly)phenol-rich supplementation on cognitive function and neuroprotective measures in young and middle-aged adults (<60 years old). A total of 4303 records were screened by two researchers using the PICOS criteria. Fifteen high quality (mean PEDro score = 8.8 ± 0.58) trials with 401 total participants were included in the final analyses. Information on treatment, study design, characteristics of participants, outcomes and used tools were extracted following PRISMA guidelines. When items were shown to be sufficiently comparable, a random-effects meta-analysis was used to pool estimates across studies. Effect size (ES) and its 95% confidence interval (CI) was calculated. The meta-analysis indicated that (poly)phenol supplementation significantly increased brain-derived neurotrophic factor (ES = 3.259, = 0.033), which was accompanied by higher performance in serial (7s) subtraction (ES = 1.467, = 0.001) and decreases in simple reaction time (ES = -0.926, = 0.015) and mental fatigue (ES = -3.521 = 0.010). Data related to cognitive function were skewed towards an effect from acute compared to chronic polyphenol intervention; data related to BDNF were skewed toward an effect from higher bioavailability phenolic components.
CONCLUSION
This meta-analysis provides promising findings regarding the usefulness of polyphenol-rich intervention as an inexpensive approach for enhancing circulation of pro-cognitive neurotrophic factors. These beneficial effects appear to depend on the supplementation protocols. An early acute and/or chronic application of low- to high-dose phenolic components with high bioavailability rates (≥30%) at a younger age appear to provide more promising effects.
PubMed: 32466148
DOI: 10.3390/jcm9051598 -
Foods (Basel, Switzerland) Jul 2022Cocoa is a major dietary source of polyphenols, including flavanols, which have been associated with reduced blood pressure (BP). While earlier systematic reviews and... (Review)
Review
Cocoa is a major dietary source of polyphenols, including flavanols, which have been associated with reduced blood pressure (BP). While earlier systematic reviews and meta-analyses have shown significant effects of cocoa consumption on systolic BP, limitations include small sample sizes and study heterogeneity. Questions regarding food matrix and dose of polyphenols, flavanols, or epicatechins remain. This systematic review and meta-analysis aimed to investigate the effects of ≥2 weeks of cocoa consumption as a beverage or dark chocolate in those with normal or elevated (< or ≥130 mmHg) systolic BP measured in the fasted state or over 24-h. A systematic search conducted on PubMed and Cochrane Library databases up to 26 February 2022 yielded 31 suitable articles. Independent of baseline BP, cocoa consumption for ≥2 weeks was associated with reductions in systolic and diastolic BP (p < 0.05, all). Compared with cocoa, chocolate lowered the weighted mean of resting systolic BP (−3.94 mmHg, 95% CI [−5.71, −2.18]) more than cocoa beverage (−1.54 mmHg, 95% CI [−3.08, 0.01]). When the daily dose of flavanols was ≥900 mg or of epicatechin ≥100 mg, the effect was greater. Future, adequately powered studies are required to determine the optimal dose for a clinically significant effect.
PubMed: 35804776
DOI: 10.3390/foods11131962 -
Molecules (Basel, Switzerland) Aug 2018Depression is currently treated by pharmacotherapies that can elicit debilitating side effects for patients. Novel treatment options with limited side effects are... (Meta-Analysis)
Meta-Analysis Review
Depression is currently treated by pharmacotherapies that can elicit debilitating side effects for patients. Novel treatment options with limited side effects are currently being researched. Resveratrol is a polyphenol and phytoalexin found in the skins of grapes, red wine, Japanese knotweed, and peanuts. It has been studied extensively for its antioxidant and anti-inflammatory properties. Resveratrol has also gained attention for its neuroprotective properties. The aim of the review was to examine the mechanisms by which resveratrol reduces depressive behaviors in animal models. In total, 22 studies met the established criteria for final review. Behavioral aspects of depression were investigated using validated measures such as the forced swimming test, tail suspension test, sucrose preference test, and open field test. While many physical measures were taken, three main biological mechanisms were explored: Regulation of the hypothalamic⁻pituitary⁻adrenal axis; decreased inflammation; and increased Brain-Derived Neurotrophic Factor and neurogenesis. Based on these findings, resveratrol may be deemed an effective treatment for depression in animal models at doses between 10⁻80 mg/kg/day, although higher doses had the most significant effects. Future studies should examine the effects of resveratrol on depression in humans to determine the eligibility of resveratrol as a natural antidepressant with less severe side effects.
Topics: Animals; Antioxidants; Behavior, Animal; Biomarkers; Brain; Cytokines; Depression; Disease Models, Animal; Inflammation Mediators; Models, Biological; Neural Stem Cells; Neurogenesis; Oxidative Stress; Resveratrol; Signal Transduction
PubMed: 30200269
DOI: 10.3390/molecules23092197 -
Nutrients Jun 2019Growing evidence support association between polyphenol intake and reduced risk for chronic diseases, even if there is a broad debate about the effective amount of...
Growing evidence support association between polyphenol intake and reduced risk for chronic diseases, even if there is a broad debate about the effective amount of polyphenols able to exert such protective effect. The present systematic review provides an overview of the last 10-year literature on the evaluation of polyphenol intake and its association with specific disease markers and/or endpoints. An estimation of the mean total polyphenol intake has been performed despite the large heterogeneity of data reviewed. In addition, the contribution of dietary sources was considered, suggesting tea, coffee, red wine, fruit and vegetables as the main products providing polyphenols. Total flavonoids and specific subclasses, but not total polyphenols, have been apparently associated with a low risk of diabetes, cardiovascular events and all-cause mortality. However, large variability in terms of methods for the evaluation and quantification of polyphenol intake, markers and endpoints considered, makes it still difficult to establish an evidence-based reference intake for the whole class and subclass of compounds. Nevertheless, the critical mass of data available seem to strongly suggest the protective effect of a polyphenol-rich dietary pattern even if further well targeted and methodologically sound research should be encouraged in order to define specific recommendations.
Topics: Chronic Disease; Diet; Health Promotion; Humans; Polyphenols
PubMed: 31208133
DOI: 10.3390/nu11061355 -
PloS One 2023Increasing evidence indicates a link between obesity and cognitive impairment. Furthermore, there is limited literature regarding the effect of polyphenols, a plant... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVES
Increasing evidence indicates a link between obesity and cognitive impairment. Furthermore, there is limited literature regarding the effect of polyphenols, a plant derived compounds, on executive functioning in an overweight/obese population at-risk of cognitive impairment. The aim of the present systematic review and meta-analysis of randomized controlled trials is to examine the effect of polyphenol supplementation on executive functions in overweight and/or obese populations at risk of cognitive impairment.
METHODS
A comprehensive literature search was conducted from inception to March 2023 using four electronic databases: PubMed/Medline, PsycInfo, Scopus and Cochrane trials library. Published primary research studies in English that compared the effect of polyphenols with placebo on executive function in overweight/obese adults were considered eligible for the meta-analysis. Jadad scale was used for the methodological quality rating of the included studies. Hedges g with 95% confidence intervals (CI) for endpoints were calculated using random effect model where applicable. Rosenthal's Fail-safe N, funnel plots, the Begg and Mazumdar's rank correlation test (Kendall's S statistic P-Q), Egger's linear regression test, and Duval and Tweedie's trim-and-fill test were identified for potential use as appropriate, to examine publication bias. Sensitivity analysis was conducted to examine the robustness of the results.
RESULTS AND CONCLUSION
A total of 23 RCT studies involving N = 1,976 participants were included in the review. The results of the meta-analysis revealed a non-significant effect for polyphenol supplementation on executive function (g = 0.076, CI = -0.018 to 0.170). Observations from primary studies within the meta-analysis showed a potential positive effect of polyphenol supplementation in a younger population at-risk of cognitive impairment and it is recommended to investigate this further in future studies. Moreover, the variability of the tasks used to examine executive functions as well as the adequate reporting of supplement's phenolic composition is a limitation that future work should also consider.
Topics: Adult; Humans; Overweight; Executive Function; Polyphenols; Obesity; Cognitive Dysfunction; Dietary Supplements
PubMed: 37228106
DOI: 10.1371/journal.pone.0286143 -
International Journal of Molecular... Jul 2022One of the possible alternatives for creating materials for the regeneration of bone tissue supporting comprehensive reconstruction is the incorporation of active... (Review)
Review
One of the possible alternatives for creating materials for the regeneration of bone tissue supporting comprehensive reconstruction is the incorporation of active substances whose controlled release will improve this process. This systematic review aimed to identify and synthesize in vitro studies that assess the suitability of polyphenolics as additives to polymer-ceramic composite bone regeneration materials. Data on experimental studies in terms of the difference in mechanical, wettability, cytocompatibility, antioxidant and anti-inflammatory properties of materials were synthesized. The obtained numerical data were compiled and analyzed in search of percentage changes of these parameters. The results of the systematic review were based on data from forty-six studies presented in nineteen articles. The addition of polyphenolic compounds to composite materials for bone regeneration improved the cytocompatibility and increased the activity of early markers of osteoblast differentiation, indicating a high osteoinductive potential of the materials. Polyphenolic compounds incorporated into the materials presumably give them high antioxidant properties and reduce the production of reactive oxygen species in macrophage cells, implying anti-inflammatory activity. The evidence was limited by the number of missing data and the heterogeneity of the data.
Topics: Antioxidants; Biocompatible Materials; Bone Regeneration; Ceramics; Polyphenols; Tissue Engineering
PubMed: 35806482
DOI: 10.3390/ijms23137473 -
Journal of Clinical Medicine Mar 2020As the food industry is continually involved in the development of new attractive alternative therapeutic agents, the evaluation of the beneficial impact of... (Review)
Review
CONTEXT
As the food industry is continually involved in the development of new attractive alternative therapeutic agents, the evaluation of the beneficial impact of (poly)phenols on cognitive and brain function during aging has gained increasing interest.
OBJECTIVE
This systematic review and meta-analysis aimed to evaluate the acute and chronic effects of (poly)phenol-rich diet supplementation on cognitive function and brain health in aging adults.
DATA SOURCES
PubMed and Web of Science databases were searched for relevant randomized placebo-controlled trials (RCTs) published from inception to July 2019.
STUDY SELECTION
Two researchers independently screened 4303 records, using the PICOS criteria: Participants were aging adults; Intervention was based on acute and/or chronic (poly)phenols-rich supplementation; Comparator was any comparator; Outcomes included cognitive function and neuroprotective measures; and Study design was RCTs. A third researcher was consulted when discrepancies arose. Fifteen high-quality (mean PEDro score = 8.8 ± 0.56) RCTs (total participants: 918 healthy older adults) were included in the final sample.
DATA EXTRACTION
Information on study design, employed treatment, characteristics of participants, outcomes, and the correspondent assessing methods were extracted. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Data Analysis and Results: A random-effects meta-analysis was used to pool estimates across studies. Effect size (ES) and its 95% confidence interval (CI) was calculated. Pooled results yielded a trivial ES (-0.2 to 0.03) for brain-derived neurotrophic factor and neuroinflammatory parameters and small (0.36) to moderate (0.82) ES for executive functions.
CONCLUSION
This meta-analysis failed to provide evidence regarding the neuroprotective and anti-inflammatory effect of (poly)phenols supplementation in aging adults. However, findings from individual studies, included in this systematic review, suggest polyphenol-rich supplementation may improve some cognitive and brain functions in older adults. The beneficial effect of polyphenols seems to depend on ingested dose and bioavailability. Results suggest at least an intermediate dose (≥500 mg), and intermediate (≈9%) to high (43%) bioavailability rates are needed to cross the brain blood barrier and to exert a significant effect on cognitive health.
PubMed: 32204500
DOI: 10.3390/jcm9030835 -
Frontiers in Nutrition 2021Life expectancy steadily increases, and so do age-associated diseases, leading to a growing population suffering from cognitive decline and dementia. Impairments in...
Life expectancy steadily increases, and so do age-associated diseases, leading to a growing population suffering from cognitive decline and dementia. Impairments in working memory (WM) and episodic memory (EM) are associated with an increased risk of developing dementia. While there are no effective pharmacological therapies to preserve or enhance cognition and to slow down the progression from mild memory complaints to dementia so far, plant-based nutrients including polyphenols have been suggested to exert beneficial effects on brain aging. This review studies whether supplementary polyphenols are effective in preserving or enhancing memory in both non-pathological and pathological aging, and whether there are polyphenol efficiency differences between WM and EM. A systematic literature search was conducted and 66 out of 294 randomized clinical trials with 20 participants or more per group, aged 40 years or older were included. These covered a daily intake of 35-1,600 mg polyphenols, e.g., flavonols, flavonoids, isoflovones, anthocyanins, and/or stilbenes, over the course of 2 weeks to 6.5 years duration. In total, around half of the studies reported a significantly improved performance after polyphenol administration compared to control, while three studies reported a worsening of performance, and the remainder did not observe any effects. According to pooled WM and EM meta-analysis of all memory outcomes reported in 49 studies, overall effect size for WM and EM indicated a significant small positive effect on EM and WM with similar estimates ( ~ 0.24, < 0.001), with large study heterogeneity and significant Funnel asymmetry tests suggesting a positivity bias. These results remained similar when excluding studies reporting extremely large positive effect sizes from the meta-analyses. While and isoflavones did not show benefits in subgroup meta-analyses, those suggested some effects in extracts containing anthocyanins, other flavonoids and resveratrol, again potentially resulting from publication bias. To conclude, a systematic review and meta-analysis indicate that short- to moderate-term polyphenol interventions might improve WM and EM in middle-to older aged adults, however, publication bias in favor of positive results seems likely, rendering definite conclusions difficult. Future studies with larger, more diverse samples and sensitive monitoring of cardiovascular, metabolic and beginning brain pathologies as well as longer follow-up are needed to better understand the impact of age, (beginning) pathologies, gender, and long-term use on polyphenol action.
PubMed: 35155509
DOI: 10.3389/fnut.2021.720756 -
Antioxidants (Basel, Switzerland) Nov 2022Gestational Diabetes Mellitus (GDM) and preeclampsia (PE) affects 6-25% of pregnancies and are characterized by an imbalance in natural prooxidant/antioxidant...
Gestational Diabetes Mellitus (GDM) and preeclampsia (PE) affects 6-25% of pregnancies and are characterized by an imbalance in natural prooxidant/antioxidant mechanisms. Due to their antioxidant and anti-inflammatory properties, polyphenols consumption during the pregnancy might exert positive effects by preventing GDM and PE development. However, this association remains inconclusive. This systematic review and metanalysis is aimed to analyze the association between polyphenol-rich food consumption during pregnancy and the risk of GDM and PE. A systematic search in MEDLINE, EMBASE, and Web of Science (Clarivate Analytics, London, United Kingdom) for articles dated between 1 January 1980 and July 2022 was undertaken to identify randomized controlled trials and observational studies evaluating polyphenol-rich food consumption and the risk of GDM and PE. The Newcastle-Ottawa Scale was used to evaluate the quality of these included studies. Twelve studies were included, of which eight articles evaluated GDM and four studied PE. A total of 3785 women presented with GDM (2.33%). No association between polyphenol consumption and GDM was found (ES = 0.85, 95% CI 0.71-1.01). When total polyphenol intake was considered, a lower likelihood to develop GDM was noted (ES = 0.78, 95% CI 0.69-0.89). Furthermore, polyphenol consumption was not associated with PE development (ES = 0.90, 95% CI 0.57-1.41). In conclusion, for both outcomes, pooled analyses showed no association with polyphenol-rich food consumption during pregnancy. Therefore, association of polyphenol intake with a decreased risk of GDM and PE remains inconclusive.
PubMed: 36421480
DOI: 10.3390/antiox11112294