Consumption Of Polyphenol-rich Foods Research Articles

Aerobic exercise combined with chlorogenic acid exerts neuroprotective effects and reverses cognitive decline in Alzheimer's disease model mice (APP/PS1) via the SIRT1/ /PGC-1α/PPARγ signaling pathway.

Alzheimer's disease (AD) is a prevalent neurodegenerative disease account for 60-80% of the total number of people with dementia, but its treatment and prevention strategies are still in a long process of exploration. It has been reported that a healthy lifestyle may be an effective non-pharmacological intervention for the prevention and treatment of AD, including increased physical activity and the consumption of polyphenol-rich foods. This study, therefore, investigated the effects of 8 weeks of moderate-intensity aerobic exercise (EX), administration of chlorogenic acid administration (GCA), and a combination of both (EX+GCA) on β-amyloid (Aβ) deposition, inflammatory factors, oxidative stress markers, neuronal damage, and cognitive performance in the brains of AD model mice (APP/PS1) and which signaling pathways may be responsible for these effects. The study used Western blot to detect the expression of signaling pathway-related proteins, enzyme-linked immunosorbent assay to detect the expression of inflammatory factors, hematoxylin-eosin staining to detect hippocampal neuronal morphology, immunohistochemistry to detect changes in Aβ deposition in the hippocampus, an oxidative stress marker kit to detect oxidative stress status and the Morris water maze to detect changes in cognitive performance. This study showed that an 8-week intervention (EX/GCA/EX+GCA) activating the SIRT1/PGC-1α signaling pathway improved oxidative stress, neuroinflammation, Aβ deposition, and cognitive performance in mice. However, there was no obvious difference between the EX and GCA groups. In contrast, the combined EX+GCA intervention was significantly better than phase EX or GCA. Our study suggests that although relief of Aβ deposition, neuroinflammation, oxidative stress, neuronal damage, and cognitive decline could also be achieved with EX or GCA, the combined EX+GCA intervention showed better results. These relief effects on AD-related conditions may be obtained by mediating the activation of the SIRT1/PGC-1α signaling pathway. This study is the first to explore the improvement of AD-related conditions with a combined lifestyle of EX+GCA. This healthy lifestyle could be a candidate option for the treatment of AD.

Determination of total phenolic content in different vegetables

The word polyphenol is that chemical substance having more than one phenol group. Polyphenols represent a variety of compounds of plant origin. Polyphenols have potential use in the human body. They act as antioxidants preventing oxidation of other molecules by formation of free radicals in the body. Most of the polyphenols have properties of reducing agents. They protect cell constituents against oxidative damage. Therefore polyphenols reduce risk of various degenerative diseases related to oxidative stress. In addition to antioxidant properties, they also have antimicrobial as well as anti-inflammatory properties. They enhance body immunity. Polyphenol intake or consumption of polyphenol-rich foods has been studied in several epidemiological studies. Many studies on the antioxidant properties of vegetables suggested that vegetables are excellent dietary sources of natural antioxidants. Polyphenols are natural antioxidants present in all foods. The study was conducted to determine total phenolic content in various vegetables. Total phenolic content estimated in vegetables were compared. Total phenols are estimated by Folin Denis reagents that produce blue color with polyphenols. Tannic acid was used as standard and results were expressed as tannic acid equivalent (Singh and Jambunathan, 1981). Result: Total polyphenol contents in present study showed variation within vegetables estimated. Mean polyphenol content in vegetables was found to be highest 5.3g/100g in amla, followed by mint 1.1g/100g, 844 mg/100g in coriander green and 586 mg/100g in lady finger. Amla was characterized as the highest polyphenol content (538 mg/100g) on a fresh weight basis, whereas the lowest mean polyphenol content (17.50mg/100g) was found in cucumber. Conclusion: fruits and vegetables must be included in our daily diet for good health.

Effect of Passiflora setacea juice and its phenolic metabolites on insulin resistance markers in overweight individuals and on microglial cell activity.

Passiflora setacea (PS) is a species of wild Brazilian passion fruit, rich in bioactive compounds. Scientific evidence suggests that food rich in polyphenols can modulate inflammation, thereby playing an important role in preventing chronic non-communicable diseases, such as type 2 diabetes (DT2) and cardiovascular diseases (CVD). This study aimed to investigate the effect of PS consumption on metabolic and inflammatory biomarkers in overweight male volunteers and to identify the underlying mechanism of action using an in vitro study using phenolic metabolites isolated from the plasma of volunteers at physiologically relevant concentrations. Volunteers participated in a double-blind, placebo-controlled (PB) study with two phases: phase I (acute study) and phase II (chronic study). In phase I, 15 volunteers ingested a single dose of 50 g, 150 g of PS pulp and PB in three different interventions. In phase II, nine volunteers ingested 50 g of PS or PB for 14 days. Blood samples were collected before (T0 h) and 3 h (T3 h) (phase I) or 15 days after (phase II) ingestion of PS or PB. Blood biochemical markers, HOMA IR, and inflammatory markers were analyzed and data on BMI, waist circumference, and consumption of polyphenol-rich foods were collected. Phenolic metabolites were extracted from plasma by solid-phase separation and were used to treat BV-2 cells stimulated by LPS or anacardic acid to assess p50, p65 and PPAR-γ activation. It was observed that the consumption of a single dose of PS juice significantly reduced basal insulin levels and HOMA IR. After prolonged consumption for two weeks, PS contributed to the reduction of circulating levels of IL-6. BV-2 cells treated with PS phenolic metabolites showed increased PPAR-γ activity, which resulted in an anti-inflammatory and anti-diabetic effect of PS metabolites. In conclusion, PS juice consumption exerts beneficial effects on inflammatory markers in overweight individuals, being a possible and important tool in the prevention of T2D and CVD in risk groups.

Polyphenol consumption and endurance exercise performance: A systematic review and meta-analysis of randomised controlled trials

Introduction: Consumption of polyphenols is proposed to reduce oxidative damage and increase nitric oxide synthesis and availability, thereby inducing physiological effects that enhance endurance exercise performance. Thus, the objective of this study was to systematically review the literature to evaluate the effects of consuming polyphenol-rich foods on endurance exercise performance. Methods: This study comprised a subanalysis of a larger systematic review. Electronic searches of Scopus, Web of Science, Ovid Medline, EMBASE and SportDiscus databases were performed. Studies were included if they involved consumption of foods containing polyphenols, and a measure of endurance exercise performance was reported. Risk of bias was assessed using the Cochrane RoB 2.0 and random effects meta-analysis was conducted, with subgroup analyses performed based on food type, sex, fitness level, and supplementation dosage and duration. Results: Data from 58 studies met eligibility criteria, with 55 studies included in the meta-analysis. Meta-analysis identified trivial but significant benefits for the overall consumption of polyphenol-rich foods on endurance exercise performance (SMD= 0.17, p<0.001). When evaluated by food type, grape, (nitrate-depleted) beetroot, French maritime pine, Montmorency cherry and pomegranate exhibited significant ergogenic effects, while no significant effects were evident for New Zealand blackcurrant, cocoa, ginseng, green tea or raisins. Significant positive effects were evident following both acute and multiple-day supplementation and meta-regression indicated that total polyphenols consumed did not moderate effect size. No effect of polyphenol consumption on exercise performance was found in females (SMD= 0.01, p=0.95), but small to moderate effects (SMD=0.21-0.76, p<0.001) were found in males across a range of fitness levels (V̇O2max 41-71 ml.kg.min-1). Limited evidence supported polyphenol-rich foods enhancing nitric oxide availability, improving vascular function, reducing oxidative damage or other physiological indicators that may explain these ergogenic benefits. Considerable heterogeneity in effect sizes of included studies was present, which may reflect variation in polyphenol bioavailability between foods, differences in study designs and subject characteristics. Discussion: Foods rich in polyphenols provide benefits for endurance exercise performance in males, but not females. These sex-specific benefits were observed across a range of fitness levels, from untrained to well-trained athletes. There is limited direct evidence of the mechanisms underpinning these effects. Other: The review protocol was registered on the Open Science Framework (https://osf.io/u7nsj). My co-authors and I acknowledge that we have no conflict of interest of relevance to the submission of this abstract.

Effect of Polyphenol-Rich Foods, Juices, and Concentrates on Recovery from Exercise Induced Muscle Damage: A Systematic Review and Meta-Analysis.

Objectives. To determine the effects of consuming polyphenol-rich foods, juices and concentrates on recovery from exercise-induced muscle damage (EIMD). Method. Eligibility criteria. Randomised and quasi-randomised placebo-controlled trials with a parallel or cross-over design evaluating the effects of consuming polyphenol-rich foods, juices and concentrates on recovery from EIMD in humans. Eligible studies included at least one of the primary outcome measures: maximal isometric voluntary contraction; MIVC, delayed onset muscle soreness; DOMS, or countermovement jump; CMJ. Information sources. AMED, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform, PUBMED, SCOPUS (Elsevier), SPORTDiscus (EBSCO), and the UK Clinical Trials Gateway were searched from inception to September 2020. Risk of bias and quality of evidence. Risk of bias was assessed using Cochrane Risk of Bias 2 tool. Quality of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation framework. Synthesis of results. Random effects models were used to determine the effect of polyphenol supplementation on recovery from EIMD. Data are presented as standardised mean differences (SMD) with 95% confidence intervals (CI). Results. Included studies. Twenty-five studies were included; 15 had a parallel, and 10 had a cross-over design. A total of 527 participants (male: n = 425; female: n = 102) were included in the meta-analysis. Synthesis of results. Consumption of polyphenol-rich foods, juices and concentrates accelerated recovery of MIVC immediately post-exercise (SMD = 0.23, 95% CI 0.04, 0.42; p = 0.02; low-quality evidence), 24 h (SMD = 0.39, 95% CI 0.15, 0.62; p = 0.001; low-quality evidence), 48 h (SMD = 0.48, 95% CI 0.28, 0.67; p < 0.001; moderate-quality evidence), 72 h (SMD = 0.29, 95% CI 0.11, 0.46; p = 0.001; low-quality evidence) and 96 h post-exercise (SMD = 0.50, 95% CI 0.16, 0.83; p = 0.004; very low-quality evidence). DOMS was reduced at 24 h (SMD = −0.29, 95% CI −0.47, −0.11; p = 0.002; low-quality evidence), 48 h (SMD = −0.28, 95% CI −0.46, −0.09; p = 0.003; low-quality evidence) and 72 h post-exercise (SMD = −0.46, 95% CI −0.69, −0.24; p < 0.001; very low-quality evidence). CMJ height was greater immediately post-exercise (SMD = 0.27, 95% CI 0.01, 0.53; p = 0.04; low-quality evidence), at 24 h (SMD = 0.47, 95% CI 0.11, 0.83; p = 0.01; very low-quality evidence), 48 h (SMD = 0.58, 95% CI 0.24, 0.91; p < 0.001; very low-quality evidence) and 72 h post-exercise (SMD = 0.57, 95% CI 0.03, 1.10; p = 0.04; very low-quality evidence). Polyphenol supplementation did not alter creatine kinase, c-reactive protein, and interleukin−6 at any time points. At 72 h post-exercise, protein carbonyls (SMD = −0.64, 95% CI −1.14, −0.14; p = 0.01) were reduced. Discussion. Limitations of evidence. Risk of bias was high for 10 studies and moderate for 15. Sensitivity analyses excluding the high risk of bias studies reduced the SMDs for MIVC and DOMS, and for CMJ effects at 24 and 48 h were no longer statistically significant. Interpretation. Consuming polyphenol-rich foods, juices and concentrates accelerated recovery of muscle function while reducing muscle soreness in humans. Maximal benefit occurred 48–72 h post-exercise, however, the certainty of the evidence was moderate to very low. Supplementation could be useful when there is limited time between competitive events and impaired recovery could negatively impact performance.

Reductions in Postprandial Plasma Allantoin Concentrations With Increasing Doses of Polyphenol Rich Curry Intake - A Randomized Crossover Trial.

While dietary or supplementary antioxidants are thought to inhibit or delay oxidation of biological molecules, their utility in vivo has been marred by equivocal evidence. Consumption of polyphenol rich foods has been thought to alleviate postprandial oxidative stress and/or improve endothelial function. Although, previous studies suggested the utility of allantoin as a biomarker of oxidative stress, controlled dose response studies with dietary antioxidants to test this in humans have been limited. We therefore investigated the effects of 2 doses of polyphenol rich curry consumption on postprandial plasma concentrations of allantoin, allantoin to uric acid ratio, F2-isoprostanes using liquid chromatography-tandem mass spectrometry (LCMS-MS) and measured endothelial function using peripheral arterial tonometry (endoPAT). In a randomized controlled crossover trial in 17 non-smoking, healthy, Chinese men, aged 23.7 ± 2.4 years and BMI 23.1 ± 2.3 kg/m2, the volunteers consumed 3 test meals in a random order, consisting of either non-curry Dose 0 Control (D0C, 0 g spices), or Dose 1 Curry (D1C, 6 g spices) or Dose 2 Curry (D2C, 12 g spices), after overnight fast. There were significant reductions in postprandial allantoin concentrations (p < 0.001) and allantoin to uric acid ratio (p < 0.001) at 2 h and 3 h following test meal consumption, indicating improvements in postprandial redox balance with increasing curry doses, although there were no differences between treatments on F2-isoprostane concentrations or on RHI (measured at 2 h only). Allantoin may have a utility as a biomarker of redox balance, in an acute setting. The study was registered at www.clinicaltrials.gov (Identifier No. NCT02599272).

Polyphenols and Microvascular Function in Humans: A Systematic Review.

Polyphenol-rich dietary sources are acknowledged to have potential cardiovascular health benefits, particularly in reducing cardiovascular disease risk. This systematic review sought to determine the effect of polyphenol-rich foods and beverages upon microvascular function, which is of considerable importance in its contribution towards the pathophysiology of microvascular-related complications but also in the future development of (macro-vessel) cardiovascular disease. Overall, consumption of polyphenol-rich foods and beverages demonstrate improved microvascular function, although this is dependent upon the polyphenol source, the dose of the product, the duration of consumption and the population group studied. Most subgroups reviewed suggest an overall beneficial effect on microvascular function, particularly grape-derived products, cocoa, tea, pine bark and Rutaceae aurantiae. Other groups remain equivocal and require further study due to the limited research performed to date. Polyphenols are abundant in the human diet and this systematic review demonstrates that they are an inexpensive, non-pharmacological approach for improving cardiovascular health in currently healthy individuals and in populations with microvascular dysfunction.

Strawberry consumption improves aging-associated impairments, mitochondrial biogenesis and functionality through the AMP-activated protein kinase signaling cascade

Dietary polyphenols have been recently proposed as activators of the AMP-activated protein kinase (AMPK) signaling pathway and this fact might explain the relationship between the consumption of polyphenol-rich foods and the slowdown of the progression of aging. In the present work, the effects of strawberry consumption were evaluated on biomarkers of oxidative damage and on aging-associated reductions in mitochondrial function and biogenesis for 8weeks in old rats. Strawberry supplementation increased antioxidant enzyme activities, mitochondrial biomass and functionality, and decreased intracellular ROS levels and biomarkers of protein, lipid and DNA damage (P<0.05). Furthermore, a significant (P<0.05) increase in the expression of the AMPK cascade genes, involved in mitochondrial biogenesis and antioxidant defences, was also detected after strawberry intake. These in vivo results were then verified in vitro on HepG2 cells, confirming the involvement of AMPK in the beneficial effects exerted by strawberry against aging progression.

Can Dietary Polyphenols Prevent the Formation of Toxic Compounds from Maillard Reaction?

Polyphenols are functional compounds in edible vegetable and food such as tea, coffee and red wine and increasing evidence demonstrates a positive link between consumption of polyphenol-rich foods and disease prevention. In this review we have focused on the current knowledge of the potential anti-glycation effects of polyphenols, particularly in regard to their influence on Maillard reaction, a non-enzymatic reaction between amino acids and reducing sugars that contributes to the production of toxic compounds, mainly reactive carbonyl species, advanced glycation end-products (AGEs) and other toxicants. The Maillard reaction occurs in the human body during hyperglycemic condition, but it is well known as browning reaction in thermally processed foods and it is responsible for flavor and toxicant formation. Dietary polyphenols can have anti-glycation effects and actively participate in Maillard reaction, mitigating the AGE formation and the heat-induced production of toxic compounds. In a time in which the role of a healthy diet in the prevention of chronic diseases is welcome and the borderline between food and medicine is becoming very thin, an improved mechanistic knowledge of how polyphenols can function to reduce harmful and unhealthy substances is mandatory.

Dietary Polyphenols as Potential Remedy for Dementia.

With increasing life expectancy as a result of better quality of life and improved health care, the incidence of aging related diseases and disorders is heading toward epidemic proportions. Dementia, a spectrum of neurological diseases associated with aging, is an increasingly prevalent disease. No cure exists yet for dementia; however, there are many potential candidates for treatment of dementia that merit more exploration. Polyphenols, which constitute one such class of compounds, are dietary agents that are globally found in commonly consumed food. Many processes that are associated with the pathophysiology of dementia can be modulated by polyphenols. Polyphenolic compounds can alleviate oxidative stress by acting as direct scavengers of free radicals and clearing superoxide and hydroxyl radicals and by increasing the level of antioxidant enzymes such as glutathione peroxidase. They also chelate metal ions to prevent free radical formation. Polyphenols can also combat inflammation by affecting transcription factors such as NF-κB. Some polyphenols may have the potential to inhibit excitotoxicity by regulating intracellular calcium ion concentration, inhibiting glutamate receptors and increasing glutamate reuptake at the synapse. The cognitive decline in dementia due to decreased availability of acetylcholine can also be countered by polyphenols that inhibit acetyl-cholinesterase activity. Taken together, these findings suggest that increasing the consumption of polyphenol rich food may alleviate the effects of dementia. Moreover, their effects on controlling multiple mechanisms that are associated with dementia may also prevent or slow down the onset and progress of this devastating disease.

Effects of Polyphenol, Measured by a Biomarker of Total Polyphenols in Urine, on Cardiovascular Risk Factors After a Long-Term Follow-Up in the PREDIMED Study.

Several epidemiological studies have shown an inverse association between the consumption of polyphenol-rich foods and risk of cardiovascular diseases. However, accuracy and reliability of these studies may be increased using urinary total polyphenol excretion (TPE) as a biomarker for total polyphenol intake. Our aim was to assess if antioxidant activity, measured by a Folin-Ciocalteu assay in urine, is correlated with an improvement in cardiovascular risk factors (blood pressure and serum glucose, cholesterol, HDL-cholesterol, LDL-cholesterol, and triglyceride concentrations) in an elderly population at high risk. A longitudinal study was performed with 573 participants (aged 67.3 ± 5.9) from the PREDIMED study (ISRCTN35739639). We used Folin-Ciocalteu method to determine TPE in urine samples, assisting with solid phase extraction. Participants were categorized into three groups according to changes in TPE. Multiple linear regression models were used to assess relationships between TPE and clinical cardiovascular risk factors, adjusting for potential confounders. After a 5-year follow-up, significant inverse correlations were observed between changes in TPE and plasma triglyceride concentration (β = −8.563; P = 0.007), glucose concentration (β = −4.164; P = 0.036), and diastolic blood pressure (β = −1.316; P = 0.013). Our results suggest that the consumption of more polyphenols, measured as TPE in urine, could exert a protective effect against some cardiovascular risk factors.

Upregulation of Heme Oxygenase-1 in Response to Wild Thyme Treatment Protects against Hypertension and Oxidative Stress.

High blood pressure is the most powerful contributor to the cardiovascular morbidity and mortality, and inverse correlation between consumption of polyphenol-rich foods or beverages and incidence of cardiovascular diseases gains more importance. Reactive oxygen species plays an important role in the development of hypertension. We found that wild thyme (a spice plant, rich in polyphenolic compounds) induced a significant decrease of blood pressure and vascular resistance in hypertensive rats. The inverse correlation between vascular resistance and plasma heme oxygenase-1 suggests that endogenous vasodilator carbon monoxide generated by heme oxidation could account for this normalization of blood pressure. Next product of heme oxidation, bilirubin (a chain-breaking antioxidant that acts as a lipid peroxyl radical scavenger), becomes significantly increased after wild thyme treatment and induces the reduction of plasma lipid peroxidation in hypertensive, but not in normotensive rats. The obtained results promote wild thyme as useful supplement for cardiovascular interventions.

Daily consumption of red grape cell powder in a dietary dose improves cardiovascular parameters: a double blind, placebo-controlled, randomized study

Consumption of polyphenol-rich food and food ingredient such as grape and grape products improved various cardiovascular parameters. In this study, we investigate the effect of dietary daily consumption of red grape cell powder (RGC) on blood pressure (BP) and flow-mediated dilatation (FMD) as well as on oxidative stress in 50 subjects with prehypertension and mild hypertension. The subjects were randomized into groups that consumed 200, 400 mg RGC or placebo daily for 12 weeks. RGC consumption was associated with an improvement of FMD (p = 0.013). There was a significant decrease in lipid peroxidation (p = 0.013) after 12 weeks in a combined RGC-treated group. The diastolic BP decreased significantly in the 200 mg RGC group compared to the placebo group (p = 0.032). Our results indicate that a daily supplementation, of red grape cell powder, for 12 weeks affects endothelial function, diastolic BP and oxidative stress without any adverse effects.

Curcumin improves endothelial dysfunction and vascular remodeling in 2K-1C hypertensive rats by raising nitric oxide availability and reducing oxidative stress

Oxidative stress plays a role in maintaining high arterial blood pressure and contributes to the vascular changes that lead to hypertension. Consumption of polyphenol-rich foods has demonstrated their beneficial role in the prevention and treatment of hypertension. Curcumin (CUR), a phenolic compound present in the rhizomes of turmeric, possesses cardiovascular protective, anti-inflammatory and antioxidant properties. The present study was designed to investigate the protective effect of CUR on 2kidney-1clip (2K-1C)-induced hypertension, endothelial dysfunction, vascular remodeling and oxidative stress in male Sprague-Dawley rats. Sham operated or 2K-1C rats were treated with CUR at a dose of 50 or 100 mg/kg/day (or vehicle). After 6 weeks of treatment, CUR ameliorated hemodynamic performance in 2K-1C hypertensive rats (P < 0.05), by reducing blood pressure, increasing hindlimb blood flow and decreasing hindlimb vascular resistance. Hemodynamic restoration was associated with a reduction in plasma angiotensin converting enzyme level. Endothelium-dependent vasorelaxation, in response to acetylcholine, of aortic rings isolated from 2K-1C hypertensive rats-treated with CUR was significantly increased (P < 0.05). CUR also attenuated hypertension-induced oxidative stress and vascular structural modifications. These effects were associated with elevated plasma nitrate/nitrite, upregulated eNOS expression, downregulated p47phox NADPH oxidase and decreased superoxide production in the vascular tissues. The overall findings of this study suggest the mechanisms responsible for the antihypertensive action of CUR in 2K-1C hypertension-induced endothelial dysfunction and vascular remodeling involve the improvement NO bioavailability and a reduction in oxidative stress.

Activation of eNOS by Polyphenol-rich Products and Polyphenolic Compounds

Numerous epidemiological studies indicate that consumption of polyphenol-rich food and beverages is associated with a protective effect on the cardiovascular system. The beneficial effect has been attributable to several mechanisms including the improvement of the vascular function. Indeed, polyphenols have been shown to be potent stimulators of endothelial vasoprotective mechanisms including the formation of nitric oxide (NO) and the induction of endothelium-derived hyperpolarization (EDH). The aim of this review is to provide a non-exhaustive analysis of the literature regarding polyphenols-rich sources capable of activating endothelial NO synthase and the characterization of the underlying mechanism as well as the beneficial effects of polyphenols on the endothelial function in both experimental models of cardiovascular diseases and in Humans.

Consumption of cranberry beverage improved endogenous antioxidant status and protected against bacteria adhesion in healthy humans: a randomized controlled trial

Consumption of polyphenol-rich foods is associated with lower risk from many chronic diseases. We hypothesized that a single dose of cranberry beverage would improve indices of oxidative stress, inflammation, and urinary antibacterial adhesion activity in healthy humans. Six males and 6 females (18-35 years; body mass index, 19-25 kg/m2) consumed placebo, cranberry leaf extract beverage, or low-calorie cranberry juice cocktail (LCJC) once in a randomized, double-blind, placebo-controlled cross-over experimental design trial. The washout period between beverages was 1 week. Blood was collected 0, 2, 4, 8, and 24 hours after beverage consumption for measuring oxidative and inflammatory biomarkers. Urine was collected at 0, 0 to 3, 3 to 6, 6 to 9, 9 to 12, and 24 hours postintervention to assess antibacterial adhesion activity. Consumption of cranberry leaf extract beverage elevated (P < .05) blood glutathione peroxidase activity, whereas LCJC consumption increased (P < .05) glutathione concentrations and superoxide dismutase activity compared with placebo. Cranberry leaf extract beverage and LCJC consumption had no effect on the inflammatory biomarkers measured as compared with placebo. At 0 to 3 hours postconsumption, urine from participants who consumed cranberry beverages had higher (P < .05) ex vivo antiadhesion activity against P-fimbriated Escherichia coli compared with placebo. An acute dose of cranberry beverages improved biomarkers of antioxidant status and inhibition of bacterial adhesion in urine.

EXPERIMENTAL CONSTRICTION OF FETAL DUCTUS ARTERIOSUS, OXIDATIVE STRESS, AND POLYPHENOL EXCRETION AFTER MATERNAL POLYPHENOL-RICH DIET IN LATE PREGNANCY

Maternal consumption of polyphenol-rich foods interferes with fetal ductus arteriosus flow in humans and its restriction reverses ductal constriction. We aimed to assess experimentally the interrelations of ductal dynamics, oxidative damage and polyphenol excretion after a high polyphenol intake in

High levels of Bifidobacteria are associated with increased levels of anthocyanin microbial metabolites: a randomized clinical trial.

The health benefits associated with the consumption of polyphenol-rich foods have been studied in depth, however, the full mechanism of action remains unknown. One of the proposed mechanisms is through microbiota interaction. In the present study, we aimed to explore the relationship between changes in fecal microbiota and changes in urinary phenolic metabolites after wine interventions. Nine participants followed a randomized, crossover, controlled interventional trial. After the washout period, they received red wine, dealcoholized red wine or gin for 20 days each. Polyphenol metabolites (n > 60) in urine were identified and quantified by UPLC-MS/MS and the microbial content of fecal samples was quantified by real-time quantitative PCR. Interventions with both red wine and dealcoholized red wine increased the fecal concentration of Bifidobacterium, Enterococcus and Eggerthella lenta, compared to gin intervention and baseline. When participants were categorized in tertiles of changes in fecal bacteria, those in the highest tertile of Bifidobacteria had higher urinary concentration changes in syringic acid, p-coumaric acid, 4-hydroxybenzoic acid and homovanillic acid (all anthocyanin metabolites) than those in tertile 1 (P < 0.05, all). In addition, changes of Bifidobacteria correlated positively with changes of these metabolites (r = 0.5-0.7, P < 0.05, all). Finally, the 68.5% changes in Bifidobacteria can be predicted by syringic acid and 4-hydroxybenzoic acid changes. This study confirms the important role of polyphenols as bacterial substrates and their modulatory capacity as an important field in the research of new products with prebiotic and probiotic characteristics for the food industry.

The Effect of Polyphenol Consumption on Blood Pressure

Several observational and intervention studies have found an inverse association between the risk of cardiovascular disease and the consumption of polyphenol-rich foods and beverages such as cocoa, fruit and vegetables, tea, virgin olive oil and wine. We present here an overview of the latest research on the beneficial effect of dietary polyphenols on blood pressure, focusing on the development of urine biomarkers for an accurate estimation of polyphenol intake. Total polyphenols (TP) excreted in spot urine samples have been successfully used as a biomarker of the consumption, bioavailability and accumulation of TP in a cross-sectional clinical trial. In addition, we describe how the vasoprotective effect of dietary polyphenols has been related to their ability to increase endothelial synthesis of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF)-mediated responses.

Dietary intake and major food sources of polyphenols in a Spanish population at high cardiovascular risk: The PREDIMED study

Epidemiological data have shown an inverse association between the consumption of polyphenol-rich foods and the risk of cardiovascular disease or overall mortality. A comprehensive estimation of individual polyphenol intake in nutritional cohorts is needed to gain a better understanding of this association. The aim of this study was to estimate the quantitative intake of polyphenols and the major dietary sources in the PREDIMED (PREvención con DIeta MEDiterránea) cohort using individual food consumption records. The PREDIMED study is a large, parallel-group, multicentre, randomised, controlled 5-year feeding trial aimed at assessing the effects of the Mediterranean diet on the primary prevention of cardiovascular disease. A total of 7200 participants, aged 55-80 years, completed a validated 1-year food frequency questionnaire (FFQ) at baseline. Polyphenol consumption was calculated by matching food consumption data from the FFQ with the recently developed Phenol-Explorer database on polyphenol content in foods. The mean total polyphenol intake was 820 ± 323 mg day⁻¹ (443 ± 218 mg day⁻¹ of flavonoids and 304 ± 156 mg day⁻¹ of phenolic acids). Hydroxycinnamic acids were the phenolic group with the highest consumption and 5-caffeoylquinic acid was the most abundantly ingested individual polyphenol. The consumption of olives and olive oil was a differentiating factor in the phenolic profile of this Spanish population compared with other countries. In Mediterranean countries, such as Spain, the main dietary source of polyphenols is coffee and fruits, but the most important differentiating factor with respect to other countries is the consumption of polyphenols from olives and olive oil.