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Critical Reviews in Food Science and... 2022This study aimed to review the literature on studies that evaluated resveratrol's effects supplementation on parameters of diabetes in humans. We conducted an online... (Meta-Analysis)
Meta-Analysis
This study aimed to review the literature on studies that evaluated resveratrol's effects supplementation on parameters of diabetes in humans. We conducted an online search in the following databases: Pubmed, Lilacs, Scielo, Scopus, Web of Science, Embase, and Cochrane. It included experimental studies that investigated the effects of resveratrol supplementation for diabetes treatment or prevention and its relationship with fasting blood glucose, insulin resistance, and glycated hemoglobin. Observational, non-human studies and non-randomized clinical trials were excluded. We conducted a meta-analysis to evaluate the effects of resveratrol supplementation on fasting blood glucose, insulin resistance, and glycated hemoglobin. Thirty studies were included in the review. Almost 60% demonstrated at least one significant effect of the resveratrol supplementation related to diabetes. In the meta-analysis, there was a significant effect on the reduction of insulin resistance [SMD: -0.34; CI 95%: -0.64, -0.04; = 0.01; I = 70%] and glycated hemoglobin [SMD: -0.64; CI 95%: -1.22, -0.07; = 0.01; I = 90%]. For fasting blood glucose, the results were significant only for individuals with diabetes [SMD: -0.85; CI 95%: -1.49, -0.21; = 0.01; I = 90%]. This systematic review with meta-analysis demonstrated that resveratrol supplementation has protective effects on diabetes parameters.
Topics: Blood Glucose; Diabetes Mellitus, Type 2; Dietary Supplements; Glycated Hemoglobin; Humans; Insulin Resistance; Resveratrol
PubMed: 33480264
DOI: 10.1080/10408398.2021.1875980 -
Nutrients May 2023Comprehensively compiled dietary polyphenol data is required to compare polyphenol content between foods, calculate polyphenol intake and study its association with... (Review)
Review
Comprehensively compiled dietary polyphenol data is required to compare polyphenol content between foods, calculate polyphenol intake and study its association with health and disease. The purpose of this review was to identify data on the presence and content of polyphenolic components in South African foods, with the aim of compiling the data into a database. An electronic literature search was conducted up until January 2020 using multiple databases. Additional literature was sourced from South African university repositories. A total of 7051 potentially eligible references were identified, of which 384 met the inclusion criteria. These studies provided information on food item name, geographical distribution, polyphenol type, quantity, and quantification method. Data for 1070 foods were identified, amounting to 4994 polyphenols. Spectrophotometry was the main method used for quantification of gross phenolic content in various assays such as total phenolic content (Folin-Ciocalteu assay), total flavonoid content (AlCl assay) and condensed tannin content (vanillin-HCl assay). Phenolic acids and flavonoids were the main polyphenol classes identified. This review highlights that South Africa has abundant information on the polyphenol content of foods, which could be utilised within a food composition database for the estimation of polyphenol intake for South Africa.
Topics: Humans; Diet; Flavonoids; Phenols; Polyphenols; South Africa
PubMed: 37299389
DOI: 10.3390/nu15112426 -
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 -
Nutrients Jul 2023Allergies are a common and increasing health problem affecting millions of people worldwide. This increase is attributed to genetic predisposition, air pollution,... (Review)
Review
Allergies are a common and increasing health problem affecting millions of people worldwide. This increase is attributed to genetic predisposition, air pollution, climate change, lack of physical activity, and alterations in eating habits. The Mediterranean diet (MD), which includes a lot of fruits and vegetables, whole grains, legumes, nuts, olive oil, and fish, has been linked to a variety of health benefits, including a lower risk of chronic and allergic disease. This paper explores the effects of the dietary components of the MD on food allergies. Electronic databases PubMed, Scopus, Science Direct, and EBSCO were used to conduct this systematic review. Out of 696 studies initially identified, five human and four animal studies were included. Risk of bias was determined using the Office of Health Assessment and Translation tool. In human studies, when the intervention was given during pregnancy and lactation, a beneficial effect was observed. When the intervention was given during pregnancy and until birth or to the infant for six months, no effect was observed. The animal studies indicated a beneficial effect between the food components of the MD and food allergies. Although the results are promising, the limited number of studies highlights the need for more research.
Topics: Pregnancy; Animals; Female; Humans; Diet, Mediterranean; Food Hypersensitivity; Vegetables; Fruit; Olive Oil
PubMed: 37571232
DOI: 10.3390/nu15153295 -
Current Research in Food Science 2023Epidemiology studies have indicated that polyphenol consumption was more likely to have higher sleep quality, but some results remain controversial. A general overview... (Review)
Review
Epidemiology studies have indicated that polyphenol consumption was more likely to have higher sleep quality, but some results remain controversial. A general overview of polyphenol-rich interventions on sleep disorders still lacks in the existing literature. Eligible randomized controlled trials (RCT's) literature retrieval was performed in six databases. Sleep efficiency, sleep onset latency, total sleep time, and PSQI were included as objective measures to compare the effects of placebo and polyphenols in patients with sleep disorders. Subgroup-analyses were performed based on treatment duration, geographic location, study design, and sample size. The mean differences (MD) with 95% confidence intervals (CI) were adopted for four continuous variable data of outcomes in pooled analysis. This study is registered on PROSPERO, number CRD42021271775. In total, 10 studies of 334 individuals were included. Pooled data demonstrated that administration of polyphenols decreases sleep onset latency (MD, -4.38 min; 95% CI, -6.66 to -2.11; P = 0.0002) and increases total sleep time (MD, 13.14 min; 95% CI, 7.54 to 18.74; P<0.00001), whereas they have no effect on sleep efficiency (MD, 1.04; 95% CI, -0.32 to 2.41; P = 0.13) and PSQI (MD, -2.17; 95% CI, -5.62 to 1.29; P = 0.22). Subgroup analyses further indicated that treatment duration, study design, and number of participants appeared to be responsible for the largest proportion of accountable heterogeneity. Polyphenols' potential importance is highlighted by these findings in treating sleep disorders. The development of large-scale, randomized, controlled trials is recommended to providing further evidence for therapeutic use of polyphenols in a variety of sleep difficulties.
PubMed: 36866197
DOI: 10.1016/j.crfs.2023.100462 -
Advanced Drug Delivery Reviews Sep 2021As naturally occurring bioactive products, several lines of evidence have shown the potential of polyphenols in the medical intervention of various diseases, including...
As naturally occurring bioactive products, several lines of evidence have shown the potential of polyphenols in the medical intervention of various diseases, including tumors, inflammatory diseases, and cardiovascular diseases. Notably, owing to the particular molecular structure, polyphenols can combine with proteins, metal ions, polymers, and nucleic acids providing better strategies for polyphenol-delivery strategies. This contributes to the inherent advantages of polyphenols as important functional components for other drug delivery strategies, e.g., protecting nanodrugs from oxidation as a protective layer, improving the physicochemical properties of carbohydrate polymer carriers, or being used to synthesize innovative functional delivery vehicles. Polyphenols have emerged as a multifaceted player in novel drug delivery systems, both as therapeutic agents delivered to intervene in disease progression and as essential components of drug carriers. Although an increasing number of studies have focused on polyphenol-based nanodrug delivery including epigallocatechin-3-gallate, curcumin, resveratrol, tannic acid, and polyphenol-related innovative preparations, these molecules are not without inherent shortcomings. The active biochemical characteristics of polyphenols constitute a prerequisite to their high-frequency use in drug delivery systems and likewise to provoke new challenges for the design and development of novel polyphenol drug delivery systems of improved efficacies. In this review, we focus on both the targeted delivery of polyphenols and the application of polyphenols as components of drug delivery carriers, and comprehensively elaborate on the application of polyphenols in new types of drug delivery systems. According to the different roles played by polyphenols in innovative drug delivery strategies, potential limitations and risks are discussed in detail including the influences on the physical and chemical properties of nanodrug delivery systems, and their influence on normal physiological functions inside the organism.
Topics: Animals; Drug Delivery Systems; Humans; Nanoparticles; Phytochemicals; Polyphenols
PubMed: 34280511
DOI: 10.1016/j.addr.2021.113870 -
Phytotherapy Research : PTR Oct 2023Despite the importance of polyphenol-rich fruits in decreasing cardiovascular mortality, the impact of pomegranate juice (PJ) on blood pressure is still unclear. To... (Meta-Analysis)
Meta-Analysis Review
Despite the importance of polyphenol-rich fruits in decreasing cardiovascular mortality, the impact of pomegranate juice (PJ) on blood pressure is still unclear. To determine the effect of PJ on blood pressure. PubMed, Scopus, ISI Web of Science, and Cochrane Library were searched comprehensively using relevant keywords. All studies using pomegranate juice alone were included although limited to human studies and the English language. A random-effects model and the generic inverse variance approach were used to determine quantitative data synthesis. Meta-analysis of 14 clinical trials (n = 573 individuals) demonstrated a reduction in systolic BP (SBP) with pomegranate juice (MD: -5.02 mmHg, 95% CI: -7.55 to -2.48, p < 0.001). Effect of study duration showed pomegranate juice intake ≤2 months significantly decreased SBP (MD: -4.59 mmHg, 95% CI: -7.10 to -2.08, p < 0.001) and DBP (MD: -2.94 mmHg, 95% CI: -5.25 to -0.63, p = 0.01). Consumption of ≤300 mL pomegranate juice daily reduced SBP (MD: -6.11 mmHg, 95% CI: -9.22 to -3.00, p < 0.001). Counterintuitively, >300 mL/day of pomegranate juice showed no effect on SBP (MD: -3.28 mmHg, 95% CI: -6.85 to 0.27, p = 0.07) but a significant DBP reduction occurred (MD: -3.10 mmHg, 95% CI: -5.74 to -0.47, p = 0.02). Meta-regression showed that the SBP-lowering effect of pomegranate juice was associated with the dose of supplementation (p < 0.001). Pomegranate juice appeared to decrease SBP and DBP in a dose-dependent manner, but the benefit was lost after 2 months of pomegranate juice intake.
Topics: Humans; Blood Pressure; Hypertension; Pomegranate
PubMed: 37461211
DOI: 10.1002/ptr.7952 -
Pharmaceuticals (Basel, Switzerland) Jun 2023Curcumin is a polyphenolic compound, derived from Curcuma longa, and it has several pharmacological effects such as antioxidant, anti-inflammatory, and antitumor.... (Review)
Review
Curcumin is a polyphenolic compound, derived from Curcuma longa, and it has several pharmacological effects such as antioxidant, anti-inflammatory, and antitumor. Although it is a pleiotropic molecule, curcumin's free form, which is lipophilic, has low bioavailability and is rapidly metabolized, limiting its clinical use. With the advances in techniques for loading curcumin into nanostructures, it is possible to improve its bioavailability and extend its applications. In this review, we gather evidence about the comparison of the pharmacokinetics (biodistribution and bioavailability) between free curcumin (Cur) and nanostructured curcumin (Cur-NPs) and their respective relationships with antitumor efficacy. The search was performed in the following databases: Cochrane, LILACS, Embase, MEDLINE/Pubmed, Clinical Trials, BSV regional portal, ScienceDirect, Scopus, and Web of Science. The selected studies were based on studies that used High-Performance Liquid Chromatography (HPLC) as the pharmacokinetics evaluation method. Of the 345 studies initially pooled, 11 met the inclusion criteria and all included studies classified as high quality. In this search, a variety of nanoparticles used to deliver curcumin (polymeric, copolymeric, nanocrystals, nanovesicles, and nanosuspension) were found. Most Cur-NPs presented negative Zeta potential ranging from -25 mV to 12.7 mV, polydispersion index (PDI) ranging from 0.06 to 0.283, and hydrodynamic diameter ranging from 30.47 to 550.1 nm. Selected studies adopted mainly oral and intravenous administrations. In the pharmacokinetics analysis, samples of plasma, liver, tumor, lung, brain, kidney, and spleen were evaluated. The administration of curcumin, in nanoparticle systems, resulted in a higher level of curcumin in tumors compared to free curcumin, leading to an improved antitumor effect. Thus, the use of nanoparticles can be a promising alternative for curcumin delivery since this improves its bioavailability.
PubMed: 37513855
DOI: 10.3390/ph16070943 -
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