Daily consumption of cranberry improves endothelial function in healthy adults: a double blind randomized controlled trial.

Background: Previous studies indicate cardiovascular health benefits of cranberry juice consumption. However, whether daily consumption of whole cranberries will have sustained vascular benefits in healthy individuals is currently unknown. Objective: To investigate the vascular effects of acute and daily consumption of freeze dried whole cranberry in healthy men and how effects relate to circulating cranberry (poly)phenol metabolites. Methods: A double-blind, parallel-group, randomized controlled trial was conducted in 45 healthy male adults randomly allocated to 1 month daily consumption of either cranberry (9 g powder solubilized in water equivalent to 100 g of fresh cranberries, 525 mg total (poly)phenols) or control (9 g powder, no (poly)phenols). Flow-mediated dilation (FMD, primary outcome), pulse wave velocity (PWV), aortic augmentation index (AIx), blood pressure, heart rate, blood lipids, and blood glucose were assessed at baseline and at 2 h on day 1 and after 1 month. Plasma and 24 h-urine were analyzed before and after treatment using targeted quantitative LC-MS methods including 137 (poly)phenol metabolites. Results: Cranberry consumption significantly increased FMD at 2 h and 1-month (1.1% (95% CI: 1.1%, 1.8%); ptreatment ≤ 0.001; ptreatment × time = 0.606) but not PWV, AIx, blood pressure, heart rate, blood lipids, and glucose. Of the 56 and 74 (poly)phenol metabolites quantified in plasma and urine, 13 plasma and 13 urinary metabolites significantly increased 2 h post-consumption and on day 1, respectively, while 4 plasma and 13 urinary metabolites were significantly higher after 1-month of cranberry consumption, in comparison with control. A multi-variable stepwise linear regression analysis showed that plasma cinnamic acid-4'-glucuronide, 4-hydroxybenzoic acid-3-sulfate, 2,5-dihydroxybenzoic acid, 3'-hydroxycinnamic acid, and 5-O-caffeoylquinic acid were significant independent predictors of 2 h FMD effects (R2 = 0.71), while 3'-hydroxycinnamic acid, 4-methoxycinnamic acid-3'-glucuronide, 3-(4'-methoxyphenyl)propanoic acid 3'-sulfate, and 3-(4'-methoxyphenyl)propanoic acid 3'-glucuronide predicted the 1-month FMD effects (R2 = 0.52). Conclusions: Acute and daily consumption of whole cranberry powder for 1 month improves vascular function in healthy men and this is linked with specific metabolite profiles in plasma. The National Institutes of Health (NIH)-randomized trial records held on the NIH ClinicalTrials.gov website (NCT02764749). https://clinicaltrials.gov/ct2/show/NCT02764749.

Metabolomics profile responses to changing environments in a common bean (Phaseolus vulgaris L.) germplasm collection.

Metabolomics is one of the most powerful -omics to assist plant breeding. Despite the recognized genetic diversity in Portuguese common bean germplasm, details on its metabolomics profiles are still missing. Aiming to promote their use and to understand the environment's effect in bean metabolomics profiles, 107 Portuguese common bean accessions, cropped under contrasting environments, were analyzed using spectrophotometric, untargeted and targeted mass spectrometry approaches. Although genotype was the most relevant factor on bean metabolomics profile, a clear genotype × environment interaction was also detected. Multivariate analysis highlighted, on the heat-stress environment, the existence of higher levels of salicylic acid, and lower levels of triterpene saponins. Three clusters were defined within each environment. White accessions presented the lowest content and the colored ones the highest levels of prenol lipids and flavonoids. Sources of interesting metabolomics profiles are now identified for bean breeding, focusing either on local or on broad adaptation.

Extraction and high-throughput sequencing of oak heartwood DNA: Assessing the feasibility of genome-wide DNA methylation profiling.

Tree ring features are affected by environmental factors and therefore are the basis for dendrochronological studies to reconstruct past environmental conditions. Oak wood often provides the data for these studies because of the durability of oak heartwood and hence the availability of samples spanning long time periods of the distant past. Wood formation is regulated in part by epigenetic mechanisms such as DNA methylation. Studies of the methylation state of DNA preserved in oak heartwood thus could identify epigenetic tree ring features informing on past environmental conditions. In this study, we aimed to establish protocols for the extraction of DNA, the high-throughput sequencing of whole-genome DNA libraries (WGS) and the profiling of DNA methylation by whole-genome bisulfite sequencing (WGBS) for oak (Quercus robur) heartwood drill cores taken from the trunks of living standing trees spanning the AD 1776-2014 time period. Heartwood contains little DNA, and large amounts of phenolic compounds known to hinder the preparation of high-throughput sequencing libraries. Whole-genome and DNA methylome library preparation and sequencing consistently failed for oak heartwood samples more than 100 and 50 years of age, respectively. DNA fragmentation increased with sample age and was exacerbated by the additional bisulfite treatment step during methylome library preparation. Relative coverage of the non-repetitive portion of the oak genome was sparse. These results suggest that quantitative methylome studies of oak hardwood will likely be limited to relatively recent samples and will require a high sequencing depth to achieve sufficient genome coverage.

Effects of daily consumption of wild blueberry on cognition and urinary metabolites in school-aged children: a pilot study.

PURPOSE: Acute intervention with wild blueberry (WBB) has previously revealed positive cognitive and mood effects in typically developing children; however, it is unclear whether effects persist after daily supplementation. In addition, no data have been published exploring the metabolite profiles of children following berry consumption, to our knowledge. A study of this kind could provide insight into a mechanism of action for the cognitive and mood improvements observed previously in children. The aim of this pilot study was to assess cognitive performance and urinary metabolite concentrations in healthy 7-10-year-old children across a 4 week daily WBB drink intervention. METHODS: This pilot study examined the effects of daily WBB consumption for 4 weeks (766 mg total polyphenols; 253 mg anthocyanins; equivalent to 240 g fresh blueberries per day) on cognition and mood in 15 healthy 7-10-year-old children. Polyphenol metabolites were measured in 24 h urine before and after the 4 week intervention. RESULTS: Chronic WBB-related benefits were seen on cognitively demanding trials on the modified attention network task, a task measuring executive functioning. Specifically, the WBB group maintained significantly higher accuracy on incongruent trials (96%; SE 0.03) compared with placebo participants (85%; SE 0.03; p = 0.038) after the 4 week intervention, suggesting WBB was of most benefit on the more difficult aspects of the task. No significant WBB-related effects were observed on the auditory verbal learning task or the child's version of the positive and negative affect schedule. Urinary metabolite analyses indicated significant increases in different metabolites in WBB and placebo groups after 4 week consumption. CONCLUSION: The research demonstrates 24 h WBB bioavailability in a child cohort for the first time with increases in urinary hippuric acid excretion during 2 week daily WBB consumption. This study highlights the importance of conducting a larger study in children investigating the mechanism of action behind cognitive effects using bioavailability data.

Bioavailability of naringenin chalcone in humans after ingestion of cherry tomatoes.

Chalcones are a type of flavonoids characterized by an α-ß unsaturated structural element which may react with thiol groups to activate pathways such as the Nrf2-Keap-1 system. Naringenin chalcone is abundant in the diet but little is known about its bioavailability. In this work, the bioavailability of naringenin chalcone from tomatoes was investigated in a group of healthy men (n=10). After ingestion of 600 grams of tomatoes providing a single dose of 17.3 mg naringenin chalcone, 0.2 mg of naringenin, and 195 mg naringin plasma levels of free and conjugated naringenin and naringenin chalcone (glucuronide and sulfate) were analyzed by UHPLC-QTOF-MS at 0.5, 1, 3, and 6 h post-consumption. Plasma levels of conjugated naringenin increased to about 12 nmol/L with a maximum at about 3 h. Concentrations of free naringenin hardly elevated above baseline. Plasma levels of free and conjugated naringenin chalcone significantly increased. A maximum of the conjugated chalcone was reached at about 3 h after ingestion with an average concentration of about 0.5 nmol/L. No free chalcone was detectable at baseline but low amounts of the unconjugated compound could be detected with an average maximum of 0.8 nmol/L at about 1 h after ingestion. The data demonstrate that naringenin chalcone is bioavailable in humans from cherry tomatoes as a dietary source. However, availability is poor and intramolecular cyclisation as well as extended metabolism likely contribute to the inactivation of the reactive alpha-beta unsaturated reactive center as well as the excretion of the biologically active molecule, respectively.

Human bioavailability of phenolic compounds found in common beans: the use of high-resolution MS to evaluate inter-individual variability.

Although common beans (Phaseolus vulgaris L.) are consumed worldwide, studies on the metabolic fate of phenolic compounds from common beans are still very scarce. The present work aimed to study the bioavailability of phenolic compounds in human plasma and urine, after acute consumption of a single meal of cooked common beans. Blood and urine of seven volunteers were collected before (0 h) and at different time points (1, 2, 4, 6 and 8 h for plasma and 0-2, 2-4, 4-6, 6-8 and 8-24 h for urine) after beans' intake. Ultra-high performance liquid chromatography-quadrupole-time of flight-MS (UPLC-Q-TOF-MS) was used for quantification. After beans' intake, 405 (sd 3) g, containing 188 mg of phenolic compounds (expressed as gallic acid equivalents), there was a significant increase (P < 0·05) in the plasma concentration of six metabolites and in the urinary excretion of eleven metabolites. After 1 h post-consumption, metabolites, such as kaempferol-3-O-glucuronide, showed a significant increase in plasma concentration, suggesting kaempferol's glucuronidation in the upper gastrointestinal tract. More than 50 % of the total amount of metabolites, such as 4-methylcatechol-O-sulphate and dihydrocaffeic acid-3-O-sulphate, were excreted after 8 h post-consumption, indicating colonic bacterial metabolism of the phenolic compounds. Partial least square-discriminant analysis models clearly showed clusters of metabolites, which contributed to extend the list of compounds related to cooked common beans' human intake at different time points and showed the human inter-individual variability in plasma concentration as well as in urinary excreted metabolites, after cooked common beans' intake.

Improving the reporting quality of intervention trials addressing the inter-individual variability in response to the consumption of plant bioactives: quality index and recommendations.

PURPOSE: The quality of the study design and data reporting in human trials dealing with the inter-individual variability in response to the consumption of plant bioactives is, in general, low. There is a lack of recommendations supporting the scientific community on this topic. This study aimed at developing a quality index to assist the assessment of the reporting quality of intervention trials addressing the inter-individual variability in response to plant bioactive consumption. Recommendations for better designing and reporting studies were discussed. METHODS: The selection of the parameters used for the development of the quality index was carried out in agreement with the scientific community through a survey. Parameters were defined, grouped into categories, and scored for different quality levels. The applicability of the scoring system was tested in terms of consistency and effort, and its validity was assessed by comparison with a simultaneous evaluation by experts' criteria. RESULTS: The "POSITIVe quality index" included 11 reporting criteria grouped into four categories (Statistics, Reporting, Data presentation, and Individual data availability). It was supported by detailed definitions and guidance for their scoring. The quality index score was tested, and the index demonstrated to be valid, reliable, and responsive. CONCLUSIONS: The evaluation of the reporting quality of studies addressing inter-individual variability in response to plant bioactives highlighted the aspects requiring major improvements. Specific tools and recommendations favoring a complete and transparent reporting on inter-individual variability have been provided to support the scientific community on this field.

Risk behavior for bulimia among adolescents / Comportamento de risco para bulimia em adolescentes

ABSTRACT Objective: To analyze the risk behavior for bulimia among female adolescents from public and private high schools. Methods: A cross-sectional study with a random sample of 850 female students aged 15-18 years was carried out in a city in northeastern Brazil, using the Bulimic Investigatory Test of Edinburgh (BITE) to assess the risk behavior for bulimia. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) software and the Pearson's chi-square , Fisher's exact and robust Poisson regression tests, adopting the significance level of 5%. Results: Less than half of the sample (42.0%) showed standards of dietary risk and weight control practices; in 1.4% of the sample, bulimia signs were already installed. Fear of gaining weight was reported by 62.8% of the subjects. Risk practices were lower among students from public schools; (Odds Ratio - OR - 0.82; confidence interval of 95% - 95%CI - 0.69-0.97). Among restrictive practices, fasting for a whole day was the most applied (29.9% of the students). Among individuals who were at risk situation, almost half believed to have normal eating habits (prevalence ratio - PR - 0.42; 95%CI 0.36-0.49). Individuals who consider their eating habits normal, who are afraid of gaining weight, those who seek emotional comfort in food and follow strict diets had higher risk for bulimia (p<0.05). Conclusions: The number of female adolescent students with risk behavior practices for bulimia is high, and the frequency of those unaware of this situation is also very high. Risk situations emerge as a collective health problem, and individuals from private schools were more likely to be in this situation.

RESUMO Objetivo: Analisar comportamentos de risco para bulimia em adolescentes do sexo feminino de escolas públicas e particulares. Métodos: Estudo transversal com amostra aleatória de 850 estudantes do sexo feminino, com idades entre 15 e 18 anos, realizado em cidade do Nordeste do Brasil, utilizando o Bulimic Investigatory Test of Edinburgh (BITE) para avaliar comportamentos de risco para transtornos alimentares. Os dados foram analisados utilizando o teste do qui-quadrado de Pearson, o teste exato de Fisher e a regressão de Poisson, com o software Statistical Package for the Social Sciences (SPSS), adotando o nível de significância de p<0,05. Resultados: Da amostra estudada, 42,0% apresentou padrões de risco e práticas de dieta e controle de peso e 1,4% já apresentava sinais de bulimia instalados. O medo de ganhar peso foi relatado por 62,8% das adolescentes. As práticas de risco foram menos frequentes em estudantes de escolas públicas (Odds Ratio - OR - 0,82; intervalo de confiança de 95% - IC95% - 0,69-0,97). Entre as práticas restritivas, jejum por um dia inteiro foi o mais aplicado pelas participantes (29,9%). Entre os indivíduos com situação de risco, quase metade acreditava ter hábitos alimentares normais (razão de prevalência - RP - 0,42; IC95% 0,36-0,49). Estudantes que consideram seus hábitos alimentares normais, que têm medo de ganhar peso, que procuram conforto emocional em alimentos e seguem dietas rigorosas tiveram maior risco para bulimia (p<0,05). Conclusões: O número de estudantes com práticas de comportamento de risco para bulimia é alto, e o número daquelas que desconhecem essa situação também é muito alto. As situações de risco emergem como problemas de saúde coletiva, e indivíduos de escolas particulares são mais propensos a apresentar transtornos alimentares.

RISK BEHAVIOR FOR BULIMIA AMONG ADOLESCENTS.

OBJECTIVE: To analyze the risk behavior for bulimia among female adolescents from public and private high schools. METHODS: A cross-sectional study with a random sample of 850 female students aged 15-18 years was carried out in a city in northeastern Brazil, using the Bulimic Investigatory Test of Edinburgh (BITE) to assess the risk behavior for bulimia. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) software and the Pearson's chi-square , Fisher's exact and robust Poisson regression tests, adopting the significance level of 5%. RESULTS: Less than half of the sample (42.0%) showed standards of dietary risk and weight control practices; in 1.4% of the sample, bulimia signs were already installed. Fear of gaining weight was reported by 62.8% of the subjects. Risk practices were lower among students from public schools; (Odds Ratio - OR - 0.82; confidence interval of 95% - 95%CI - 0.69-0.97). Among restrictive practices, fasting for a whole day was the most applied (29.9% of the students). Among individuals who were at risk situation, almost half believed to have normal eating habits (prevalence ratio - PR - 0.42; 95%CI 0.36-0.49). Individuals who consider their eating habits normal, who are afraid of gaining weight, those who seek emotional comfort in food and follow strict diets had higher risk for bulimia (p<0.05). CONCLUSIONS: The number of female adolescent students with risk behavior practices for bulimia is high, and the frequency of those unaware of this situation is also very high. Risk situations emerge as a collective health problem, and individuals from private schools were more likely to be in this situation.

Circulating Anthocyanin Metabolites Mediate Vascular Benefits of Blueberries: Insights From Randomized Controlled Trials, Metabolomics, and Nutrigenomics.

Potential health benefits of blueberries may be due to vascular effects of anthocyanins that predominantly circulate in blood as phenolic acid metabolites. We investigated which role blueberry anthocyanins and circulating metabolites play in mediating improvements in vascular function and explore potential mechanisms using metabolomics and nutrigenomics. Purified anthocyanins exerted a dose-dependent improvement of endothelial function in healthy humans, as measured by flow-mediated dilation. The effects were similar to those of wild blueberries containing similar amounts of anthocyanins, whereas control drinks containing fiber, minerals, or vitamins had no significant effect. Daily 1-month wild blueberry consumption increased flow-mediated dilation and lowered 24-hour ambulatory systolic blood pressure. Of the 63 anthocyanin plasma metabolites quantified, 14 and 21 correlated with acute and chronic flow-mediated dilation improvements, respectively. Injection of these metabolites improved flow-mediated dilation in mice. Daily wild blueberry consumption led to differential expression (>1.2-fold) of 608 genes and 3 microRNAs, with Mir-181c showing a 13-fold increase in peripheral blood mononuclear cells. Patterns of 13 metabolites were independent predictors of gene expression changes and pathway enrichment analysis revealed significantly modulated biological processes involved in cell adhesion, migration, immune response, and cell differentiation. Our results identify anthocyanin metabolites as major mediators of vascular bioactivities of blueberries and changes of cellular gene programs. Trial registration: NCT025208.

Plasma urolithin metabolites correlate with improvements in endothelial function after red raspberry consumption: A double-blind randomized controlled trial.

Raspberries are a rich source of ellagitannins and anthocyanins. The aim of this work was to investigate whether raspberry consumption can improve vascular function and to understand which phenolic metabolites may be responsible for the effects. A 3 arm double-blind randomized controlled crossover human intervention trial was conducted in 10 healthy males. Flow-mediated dilation (FMD) was measured at baseline, 2 h, and 24 h post-consumption of 200 g and 400 g of red raspberries containing 201 or 403 mg of total (poly)phenols, or a matched control drink. Raspberry (poly)phenol metabolites were analyzed in plasma and urine by UPLC-QTOF mass spectrometry using authentic standards. Significant improvements in FMD were observed at 2 h (1.6% (95%CI 1.2, 1.9) and 1.2% (95% CI 0.8, 1.5)) and 24 h (1.0% (95% CI 0.6, 1.2) and 0.7% (95%CI 0.2, 0.9)) post-consumption of the 200 and 400 g raspberry drinks as compared to control, respectively. Plasma ellagic acid, urolithin A-3-glucuronide and urolithin A-sulfate correlated with the improvements in FMD at 2 and 24 h post consumption, respectively. Consumption of dietary achievable amounts of red raspberries acutely improves endothelial function up to 24 h and ellagitannins may be responsible for the observed effect.

Absorption, Metabolism and Excretion of Cranberry (Poly)phenols in Humans: A Dose Response Study and Assessment of Inter-Individual Variability.

The beneficial health effects of cranberries have been attributed to their (poly)phenol content. Recent studies have investigated the absorption, metabolism and excretion of cranberry (poly)phenols; however, little is known about whether they follow a dose response in vivo at different levels of intake. An acute double-blind randomized controlled trial in 10 healthy men with cranberry juices containing 409, 787, 1238, 1534 and 1910 mg total (poly)phenols was performed. Blood and urine were analyzed by UPLC-Q-TOF-MS. Sixty metabolites were identified in plasma and urine including cinnamic acids, dihydrocinnamic, flavonols, benzoic acids, phenylacetic acids, benzaldehydes, valerolactones, hippuric acids, catechols, and pyrogallols. Total plasma, but not excreted urinary (poly)phenol metabolites, exhibited a linear dose response (r² = 0.74, p < 0.05), driven by caffeic acid 4-O-ß-d-glucuronide, quercetin-3-O-ß-d-glucuronide, ferulic acid 4-O-ß-d-glucuronide, 2,5-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, ferulic acid, caffeic acid 3-O-ß-d-glucuronide, sinapic acid, ferulic acid 4-O-sulfate, 3-hydroxybenzoic acid, syringic acid, vanillic acid-4-O-sulfate, (4R)-5-(3'-hydroxyphenyl)-γ-valerolactone-4'-O-sulfate, 4-methylgallic acid-3-O-sulfate, and isoferulic acid 3-O-sulfate (all r² ≥ 0.89, p < 0.05). Inter-individual variability of the plasma metabolite concentration was broad and dependent on the metabolite. Herein, we show that specific plasma (poly)phenol metabolites are linearly related to the amount of (poly)phenols consumed in cranberry juice. The large inter-individual variation in metabolite profile may be due to variations in the gut microbiome.

Plasma and Urinary Phenolic Profiles after Acute and Repetitive Intake of Wild Blueberry.

Recent studies have shown that blueberries may have cardiovascular and cognitive health benefits. In this work, we investigated the profile of plasma and urine (poly)phenol metabolites after acute and daily consumption of wild blueberries for 30 days in 18 healthy men. The inter-individual variability in plasma and urinary polyphenol levels was also investigated. Blood samples were collected at baseline and 2 h post-consumption on day 1 and day 30. Twenty-four-hour urine was also collected on both days. A total of 61 phenolic metabolites were quantified in plasma at baseline, of which 43 increased after acute or chronic consumption of blueberries over one month. Benzoic and catechol derivatives represented more than 80% of the changes in phenolic profile after 2 h consumption on day 1, whereas hippuric and benzoic derivatives were the major compounds that increased at 0 and 2 h on day 30, respectively. The total (poly)phenol urinary excretion remained unchanged after 30 days of wild blueberry intake. The inter-individual variability ranged between 40%-48% in plasma and 47%-54% in urine. Taken together, our results illustrate that blueberry (poly)phenols are absorbed and extensively metabolized by phase II enzymes and by the gut microbiota, leading to a whole array of metabolites that may be responsible for the beneficial effects observed after blueberry consumption.

Development and validation of a high-throughput micro solid-phase extraction method coupled with ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry for rapid identification and quantification of phenolic metabolites in human plasma and urine.

A rapid and high-throughput micro-solid phase extraction (µ-SPE) method coupled with ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC Q-TOF MS) analysis was optimized and validated for the quantification of 67 (poly)phenol metabolites in human plasma and urine using authentic standards. The method was fully validated in terms of specificity, linearity, method detection limit (MDL), method quantification limit (MQL), repeatability, intra- and inter-day precision, accuracy and matrix effects. The method proved to be specific and results showed linearity of responses for all compounds, with MDL ranging between 0.04nM and 86nM in plasma and between 0.01nM and 136nM in urine. MQL ranged between 0.14nM and 286nM in plasma and between 0.03nM and 465nM in urine. Repeatability varied between 1.7 and 9.2% in plasma and between 2.2% and 10.4% in urine. Median precision values of 8.7 and 11.5% (intra-day), and 10.8% and 10.0% (inter-day) were obtained in plasma and urine, respectively. The median recovery was 89% in both biological matrices. Matrix effects were determined and median values of -1.2% and -6.8% in plasma and urine were obtained. After method validation, 49 and 57 compounds, including phase II and gut microbial metabolites, were quantified in plasma and urine, respectively, following cranberry juice consumption. This methodology can be applied to large-scale human dietary intervention trials allowing for high sample throughput.

Cranberry (poly)phenol metabolites correlate with improvements in vascular function: A double-blind, randomized, controlled, dose-response, crossover study.

SCOPE: Cranberries are rich in potentially bioactive (poly)phenols. The aim of this paper was to investigate whether cranberry juice intake can improve vascular function in healthy men in a dose- and time-dependent manner, and to understand which of the circulating (poly)phenol metabolites correlate with vascular effects. METHODS AND RESULTS: A double-blind randomized controlled crossover trial was conducted in ten healthy males. Flow-mediated dilation (FMD), blood pressure, pulse wave velocity and augmentation index were investigated at baseline, 1, 2, 4, 6, and 8 h post-consumption of cranberry juices containing 409, 787, 1238, 1534, and 1910 mg of total cranberry (poly)phenols (TP), and a control drink. Plasma (poly)phenol metabolites were analyzed by UPLC-Q-TOF MS using authentic standards. We observed dose-dependent increases in FMD at 1, 2, 4, 6, and 8 h with a peak at 4 h and maximal effects with juice containing 1238 mg TP. A total of 60 metabolites were quantified in plasma after cranberry consumption. Twelve (poly)phenol metabolites significantly correlated with the increases in FMD, including ferulic and caffeic acid sulfates, quercetin-3-O-ß-D-glucuronide and a γ-valerolactone sulfate. CONCLUSION: (Poly)phenols in cranberry juice can improve vascular function in healthy males and this is linked to the presence of specific newly identified plasma metabolites.

Identification and quantification of novel cranberry-derived plasma and urinary (poly)phenols.

Cranberries are a rich source of (poly)phenols, in particular proanthocyanidins, anthocyanins, flavonols, and phenolic acids. However, little is known about their bioavailability in humans. We investigated the absorption, metabolism, and excretion of cranberry (poly)phenols in plasma and urine of healthy young men after consumption of a cranberry juice (787 mg (poly)phenols). A total of 60 cranberry-derived phenolic metabolites were identified using UPLC-Q-TOF-MS analysis with authentic standards. These included sulfates of pyrogallol, valerolactone, benzoic acids, phenylacetic acids, glucuronides of flavonols, as well as sulfates and glucuronides of cinnamic acids. The most abundant plasma metabolites were small phenolic compounds, in particular hippuric acid, catechol-O-sulfate, 2,3-dihydroxybenzoic acid, phenylacetic acid, isoferulic acid, 4-methylcatechol-O-sulfate, α-hydroxyhippuric acid, ferulic acid 4-O-sulfate, benzoic acid, 4-hydroxyphenyl acetic acid, dihydrocaffeic acid 3-O-sulfate, and vanillic acid-4-O-sulfate. Some benzoic acids, cinnamic acids, and flavonol metabolites appeared in plasma early, at 1-2 h post-consumption. Others such as phenylacetic acids, benzaldehydes, pyrogallols, catechols, hippuric and dihydrocinnamic acid derivatives appear in plasma later (Tmax 4-22 h). The 24 h urinary recovery with respect to the amount of (poly)phenols consumed was 6.2%. Our extensive description of the bioavailability of cranberry (poly)phenols lays important groundwork necessary to start understanding the fate of these compounds in humans.

Methods to determine effects of cranberry proanthocyanidins on extraintestinal infections: Relevance for urinary tract health.

Urinary tract infections (UTI) are one of the most frequent extraintestinal infections caused by Escherichia coli (ExPEC). Cranberry juice has been used for decades to alleviate symptoms and prevent recurrent UTI. The putative compounds in cranberries are proanthocyanidins (PAC), specifically PAC with "A-type" bonds. Since PAC are not absorbed, their health benefits in UTI may occur through interactions at the mucosal surface in the gastrointestinal tract. Recent research showed that higher agglutination of ExPEC and reduced bacterial invasion are correlated with higher number of "A-type" bonds and higher degree of polymerization of PAC. An understanding of PAC structure-activity relationship is becoming feasible due to advancements, not only in obtaining purified PAC fractions that allow accurate estimation, but also in high-resolution MS methodologies, specifically, MALDI-TOF MS. A recent MALDI-TOF MS deconvolution method allows quantification of the ratios of "A-type" to "B-type" bonds enabling characteristic fingerprints. Moreover, the generation of fluorescently labeled PAC allows visualization of the interaction between ExPEC and PAC with microscopy. These tools can be used to establish structure-activity relationships between PAC and UTI and give insight on the mechanism of action of these compounds in the gut without being absorbed.

Fluorescent labeling of cranberry proanthocyanidins with 5-([4,6-dichlorotriazin-2-yl]amino)fluorescein (DTAF).

A novel methodology was developed to elucidate proanthocyanidins (PAC) interaction with extra-intestinal pathogenic Escherichia coli (ExPEC). PAC inhibit ExPEC invasion of epithelial cells and, therefore, may prevent transient gut colonization, conferring protection against subsequent extra-intestinal infections, such as urinary tract infections. Until now PAC have not been chemically labeled with fluorophores. In this work, cranberry PAC were labeled with 5-([4,6-dichlorotriazin-2-yl]amino) fluorescein (DTAF), detected by high-performance liquid chromatography with diode-array detection and characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). We report single and double fluorescent-labeled PAC with one or two chlorine atoms displaced from DTAF in alkaline pH via nucleophilic substitution. Fluorescent labeling was confirmed by fragmentation experiments using MALDI-TOF/TOF MS. Fluorescent labeled PAC were able to promote ExPEC agglutination when observed with fluorescence microscopy. DTAF tagged PAC may be used to trace the fate of PAC after they agglutinate ExPEC and follow PAC-ExPEC complexes in cell culture assays.

Supercritical fluid extraction (SFE) of cranberries does not extract oligomeric proanthocyanidins (PAC) but does alter the chromatography and bioactivity of PAC fractions extracted from SFE residues.

Supercritical fluid extraction (SFE) removed lipophilic compounds and low molecular weight flavonoids from cranberries. However, SFE did not extract proanthocyanidins (PAC). The SFE PAC-enriched residue was submitted to fractionation on Sephadex LH-20 using ethanol, ethanol/methanol, and 80% acetone. PAC degree of polymerization (DP) and ratios of "A-type" to "B-type" interflavan bonds were compared with those of PAC fractions without SFE. Mass spectrometry showed that when SFE was used, PAC distribution was shifted toward higher DP and contained higher amounts of two and three "A-type" bonds compared to PAC fractions without SFE. The 80% acetone fraction with SFE had significantly greater extraintestinal pathogenic Escherichia coli (ExPEC) agglutination and significantly lower ExPEC invasion of enterocytes than the fraction without SFE. Cranberry PAC with higher numbers of "A-type" interflavan bonds are more bioactive in agglutinating ExPEC and inhibiting ExPEC enterocyte invasion.

Cranberry proanthocyanidins improve intestinal sIgA during elemental enteral nutrition.

BACKGROUND: Elemental enteral nutrition (EEN) decreases gut-associated lymphoid tissue (GALT) function, including fewer Peyer's patch lymphocytes and lower levels of the tissue T helper 2 (Th2) cytokines and mucosal transport protein polymeric immunoglobulin receptor (pIgR), leading to lower luminal secretory immunoglobulin A (sIgA) levels. Since we recently demonstrated that cranberry proanthocyanidins (PACs) maintain the Th2 cytokine interleukin (IL)-4 when added to EEN, we hypothesized the addition of PACs to EEN would normalize other GALT parameters and maintain luminal levels of sIgA. METHODS: Institute of Cancer Research mice were randomized (12/group) to receive chow, EEN, or EEN + PACs (100 mg/kg body weight) for 5 days, starting 2 days after intragastric cannulation. Ileum tissue was collected to measure IL-4 by enzyme-linked immunosorbent assay, pIgR by Western blot, and phosphorylated STAT-6 by microarray. Intestinal wash fluid was collected to measure sIgA by Western blot. RESULTS: Compared with chow, EEN significantly decreased tissue IL-4, phosphorylated STAT-6, and pIgR. The addition of PACs to EEN prevented these alterations. Compared with chow, EEN resulted in significantly lower levels of luminal sIgA. The addition of PACs to EEN increased luminal sIgA levels compared with EEN alone. CONCLUSIONS: This study suggests the addition of PACs to EEN may support GALT function and maintain intestinal sIgA levels compared with EEN administration alone.