Dietary flavonoid and lignan intake and gastric adenocarcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

Polyphenol intake and gastric cancer: A case-control study in the Brazilian Amazon region

BACKGROUND

Polyphenol intake has been associated with a decreased risk of some types of cancer, including gastric cancer (GC). However, few studies address this topic in the Latin American population. In the present study, we evaluated the association between polyphenol intake and the risk of GC in the Brazilian Amazon region.

METHODS

A case-control study was conducted in Belém (Amazon region) from July 2017 to February 2021. A total of 193 GC cases and 194 controls of both sexes, between 18 and 75 years old, were included in the study. Dietary data were collected using a validated food-frequency questionnaire and polyphenol intake identified using the Phenol-Explorer database. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI), with adjustement for potential confounders.

RESULTS

Cases and controls had similar total polyphenol intake (356.4 mg/1000 kcal/d and 331.1 mg/1000 kcal/d, respectively; p = 0.086). After adjusting for potential confounders, high consumption of flavan-3-ols (highest vs. lowest tertile: OR 0.41, 95% CI 0.18-0.94) and hydroxybenzoic acids (highest vs. lowest tertile: OR 0.24, 95% CI 0.10-0.56) was associated with a decreased risk of GC. The opposite was true regarding the intake of flavones (OR 2.46, 95% IC 1.17-5.18) and other polyphenols (OR 2.54, 95% IC 1.16-5.54). When stratifying according to anatomical topography, we observed that the intake of total flavonoids, flavan-3-ols, and flavanones reduced the risk of cardia GC while that of hydroxybenzoic acids reduced the risk of non-cardia GC. In addition, the intake of flavones and other polyphenols was associated with an increased risk of non-cardia GC. According to histologic subtypes, hydroxybenzoic acid intake was associated with a reduced risk of intestinal-type GC (OR 0.21, 95% IC 0.07-0.64), while flavone consumption was associated with an increased risk of diffuse-type GC (OR 2.59, 95% IC 1.05-6.42).

CONCLUSIONS

Our findings suggest that in the Brazilian Amazon region the high intake of flavan-3-ols and hydroxybenzoic acids is associated with a reduced risk of GC, suggesting a potential beneficial role of these compounds against GC.

Blueberry and Blackberry Anthocyanins Ameliorate Metabolic Syndrome by Modulating Gut Microbiota and Short-Chain Fatty Acids Metabolism in High-Fat Diet-Fed C57BL/6J Mice

In this study, blueberry (Vaccinium ssp.) anthocyanins (VA) and blackberry (Rubus L.) anthocyanins (RA) were used to investigate the effects on metabolic syndrome (MetS) and the potential mechanisms. Importantly, all of the data presented in this study were obtained from experiments conducted on mice. As a result, VA and RA reduced body weight gain and fat accumulation while improving liver damage, inflammation, glucose, and lipid metabolism induced by a high-fat diet. Moreover, VA and RA regulated the gut microbiota composition, decreasing the pro-obesity and proinflammation bacteria taxa, such as the phylum Actinobacterium and the genera Allobaculum and Bifidobacterium, and increasing those negatively associated with obesity and inflammation, such as the phylum Bacteroidetes and the genera Prevotella and Oscillospira. Additionally, the supplementation with VA and RA reversed the elevated levels of valeric, caproic, and isovaleric acids observed in the high-fat diet (HFD) group, bringing them closer to the levels observed in the Chow group. This reversal indicated that alterations in the composition and abundance of gut microbiota may contribute to the restoration of short-chain fatty acids (SCFAs) levels. Additionally, PICRUSt2 exhibited that cyanamino acid metabolism and betalain biosynthesis might be the major metabolic pathways in the HVA group compared with the HFD group, while in the HRA group, it was the phosphotransferase system. These findings suggest that VA and RA can ameliorate MetS by modulating the gut microbiota and production of SCFAs.

Association between dietary intake of flavonoids and hyperuricemia: a cross-sectional study

BACKGROUND

Previous research has demonstrated flavonoid intake was closely related to hyperuricemia. The purpose of this study was to examine whether flavonoid intake was associated with serum uric acid and hyperuricemia in U.S. adults.

METHODS

The study sample consisted of 8,760 participants enrolled in the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2010. Flavonoid consumption was measured using a two-day recall questionnaire on dietary intake. Hyperuricemia was defined based on the serum uric acid levels, determined as ≥ 7 mg/dL for males and ≥ 6 mg/dL for females. The study utilized multivariate linear regression to determine the correlation between flavonoid consumption and serum uric acid levels. Additionally, analyses involving multivariate logistic regression and restricted cubic splines (RCS) were conducted to evaluate the potential link between flavonoid consumption and hyperuricemia. All analyses were adjusted for possible confounding variables.

RESULTS

The study revealed a negative correlation between serum uric acid levels and elevated levels of anthocyanidins and flavanones, with significant p-trends of < 0.001 and 0.02 respectively. The multivariate analysis showed that anthocyanidins and flavanones intake had a significant negative association with the risk of hyperuricemia, with p-trend value being < 0.001 and 0.01, respectively. Flavan-3-ols, flavonols, and all flavonoids exhibited a non-linear association with the incidence of hyperuricemia, with significant p-nonlinear values of < 0.001, 0.04, and 0.01 respectively.

CONCLUSION

Our study demonstrated that individuals who follow a diet rich in anthocyanins and flavanones had significantly lower serum uric acid levels and a lower incidence of hyperuricemia.

Phytochemicals in Cancer Treatment and Cancer Prevention-Review on Epidemiological Data and Clinical Trials

Phytochemicals are a non-nutritive substances that are present in plants and contribute significantly to their flavor and color. These biologically active compounds are classified into five major groups, namely phenolics, carotenoids, organosulfur compounds, nitrogen-containing compounds, and alkaloids, and are known for their potential health benefits in the prevention of various diseases, including cancer. The purpose of this review article is to explore the potential therapeutic benefits of the dietary phytochemicals, such as flavonoids, phenolic acids, phytosterols, carotenoids, and stilbenes, in cancer treatment and prevention based on the epidemiological studies and clinical trials. Although the majority of epidemiological studies report a significant advantage of the heightened phytochemical consumption and increased serum levels of these compounds, linking increased exposure with a lower cancer risk across most cancer types, these effects could not be replicated in the most available clinical trials. In fact, many of these trials were withdrawn early due to a lack of evidence and/or risk of harm. Despite the strong anticancer effect of phytochemicals, as well as their proven efficacy in multiple epidemiological studies, there is still a great need for human studies and clinical trials, with great caution regarding the safety measures. This review article provides an overview of the epidemiological and clinical evidence supporting the potential chemopreventive and anticancer properties of phytochemicals, with a focus on the need for further research in this area.

Current Understanding of Flavonoids in Cancer Therapy and Prevention

Cancer is a major cause of death worldwide, with multiple pathophysiological manifestations. In particular, genetic abnormalities, inflammation, bad eating habits, radiation exposure, work stress, and toxin consumption have been linked to cancer disease development and progression. Recently, natural bioactive chemicals known as polyphenols found in plants were shown to have anticancer capabilities, destroying altered or malignant cells without harming normal cells. Flavonoids have demonstrated antioxidant, antiviral, anticancer, and anti-inflammatory effects. Flavonoid type, bioavailability, and possible method of action determine these biological actions. These low-cost pharmaceutical components have significant biological activities and are beneficial for several chronic disorders, including cancer. Recent research has focused primarily on isolating, synthesizing, and studying the effects of flavonoids on human health. Here we have attempted to summarize our current knowledge of flavonoids, focusing on their mode of action to better understand their effects on cancer.

Dietary Polyphenol Intake and Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Phenolic compound consumption may have a protective effect against gastric cancer (GC). Most GC studies focus on the flavonoids class, but results are conflicting and knowledge gaps remain for other classes and total polyphenol intake. This study aimed to assess the association between polyphenol intake (total, flavonoids, and other classes) and GC.

METHODS

In this systematic review and meta-analysis, the PubMed, Embase, Scopus, LILACS, Web of Science, and OpenGrey databases were searched for studies published up to 20 March 2022. Case-control and cohort studies analyzing the association between polyphenol intake and GC were included. For the meta-analysis, pooled summary estimates were calculated using a random-effects model, and the estimates extracted adjusted for most variables. Subgroup analyses were performed for subclass (e.g., flavonoids and other classes), sex, geographical area, study design, anatomical subtype, histological subtype, family history of GC and fruit and/or vegetable intake. The study was registered with PROSPERO (#CRD42022306014).

FINDINGS

The search identified 2752 records, of which 19 studies published during the period 1999-2021 including a total of 1,197,857 subjects were eligible. Polyphenol consumption reduced GC risk by 29% (RR = 0.71; 95% CI: 0.62-0.81; I² = 60.5%); while flavonoid intake decreased GC risk by 28% (RR = 0.72; 95% CI: 0.61-0.85; I² = 64.3%), similar to the reduction fort other classes (RR = 0.65; 95% CI: 0.54-0.79; I² = 72.0%). Protective effects against GC were observed in both sexes (male, RR = 0.79; 95% CI: 0.67-0.94, I² = 31.6%; female, RR = 0.65; 95% CI: 0.48-0.87, I² = 49.7%) and for intestinal subtype (RR = 0.65; 95% CI: 0.52-0.82, I² = 0.0%). By continent, polyphenol consumption reduced GC risk in both Europe (RR = 0.67; 95% CI: 0.57-0.79, I² = 44.2%) and Asia (RR = 0.67; 95% CI: 0.51-0.89, I² = 60.7%).

CONCLUSIONS

Dietary polyphenol intake decreased GC risk. The reduction was greatest in females. Most previous studies were carried out in Europe and Asia. Further studies investigating polyphenol consumption and GC in Latin American populations are warranted.

Characterization of Peroxidase and Laccase Gene Families and In Silico Identification of Potential Genes Involved in Upstream Steps of Lignan Formation in Sesame

Peroxidases and laccases are oxidative enzymes involved in physiological processes in plants, covering responses to biotic and abiotic stress as well as biosynthesis of health-promoting specialized metabolites. Although they are thought to be involved in the biosynthesis of (+)-pinoresinol, a comprehensive investigation of this class of enzymes has not yet been conducted in the emerging oil crop sesame and no information is available regarding the potential (+)-pinoresinol synthase genes in this crop. In the present study, we conducted a pan-genome-wide identification of peroxidase and laccase genes coupled with transcriptome profiling of diverse sesame varieties. A total of 83 and 48 genes have been identified as coding for sesame peroxidase and laccase genes, respectively. Based on their protein domain and Arabidopsis thaliana genes used as baits, the genes were classified into nine and seven groups of peroxidase and laccase genes, respectively. The expression of the genes was evaluated using dynamic transcriptome sequencing data from six sesame varieties, including one elite cultivar, white vs black seed varieties, and high vs low oil content varieties. Two peroxidase genes (SiPOD52 and SiPOD63) and two laccase genes (SiLAC1 and SiLAC39), well conserved within the sesame pan-genome and exhibiting consistent expression patterns within sesame varieties matching the kinetic of (+)-pinoresinol accumulation in seeds, were identified as potential (+)-pinoresinol synthase genes. Cis-acting elements of the candidate genes revealed their potential involvement in development, hormonal signaling, and response to light and other abiotic triggers. Transcription factor enrichment analysis of promoter regions showed the predominance of MYB binding sequences. The findings from this study pave the way for lignans-oriented engineering of sesame with wide potential applications in food, health and medicinal domains.

Effect of cocoa flavanol supplementation for the prevention of cardiovascular disease events: the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial

BACKGROUND

Cocoa extract is a source of flavanols that favorably influence vascular risk factors in small and short-term trials, yet effects on clinical cardiovascular events are untested.

OBJECTIVES

We examined whether cocoa extract supplementation decreases total cardiovascular disease (CVD) among older adults.

METHODS

We conducted a randomized, double-blind, placebo-controlled, 2-by-2 factorial trial of cocoa extract supplementation and multivitamins for prevention of CVD and cancer among 21,442 US adults (12,666 women aged ≥65 y and 8776 men aged ≥60 y), free of major CVD and recently diagnosed cancer. The intervention phase was June 2015 through December 2020. This article reports on the cocoa extract intervention. Participants were randomly assigned to a cocoa extract supplement [500 mg flavanols/d, including 80 mg (-)-epicatechin] or placebo. The primary outcome was a composite of confirmed incident total cardiovascular events, including myocardial infarction (MI), stroke, coronary revascularization, cardiovascular death, carotid artery disease, peripheral artery surgery, and unstable angina.

RESULTS

During a median follow-up of 3.6 y, 410 participants taking cocoa extract and 456 taking placebo had confirmed total cardiovascular events (HR: 0.90; 95% CI: 0.78, 1.02; P = 0.11). For secondary endpoints, HRs were 0.73 (95% CI: 0.54, 0.98) for CVD death, 0.87 (95% CI: 0.66, 1.16) for MI, 0.91 (95% CI: 0.70, 1.17) for stroke, 0.95 (95% CI: 0.77, 1.17) for coronary revascularization, neutral for other individual cardiovascular endpoints, and 0.89 (95% CI: 0.77, 1.03) for all-cause mortality. Per-protocol analyses censoring follow-up at nonadherence supported a lower risk of total cardiovascular events (HR: 0.85; 95% CI: 0.72, 0.99). There were no safety concerns.

CONCLUSIONS

Cocoa extract supplementation did not significantly reduce total cardiovascular events among older adults but reduced CVD death by 27%. Potential reductions in total cardiovascular events were supported in per-protocol analyses. Additional research is warranted to clarify whether cocoa extract may reduce clinical cardiovascular events. This trial is registered at www.clinicaltrials.gov as NCT02422745.

Molecular pathogenesis and emerging targets of gastric adenocarcinoma

Gastric adenocarcinoma (GC) is a devastating disease and is the third leading cause of cancer deaths worldwide. This heterogeneous disease has several different classification systems that consider histological appearance and genomic alterations. Understanding the etiology of GC, including infection, hereditary conditions, and environmental factors, is of particular importance and is discussed in this review. To improve survival in GC, we also must improve our therapeutic strategies. Here, we discuss new targets that warrant further exploration.

Transcriptome sequencing and flavonoid metabolism analysis in the leaves of three different cultivars of Acer truncatum

Young and mature leaves of three Acer truncatum varieties with different leaf colors were examined. Transcriptome sequencing and flavonoid metabolism were used to analyze the differential gene expression associated with different leaf colors and growth stages and the relationships between gene expression and flavonoid and anthocyanin contents to improve ornamental value and develop flavonoid-rich A. truncatum. Kyoto Encyclopedia of Genes and Genomes database annotation of differentially expressed genes indicated that the following genes were related to flavonoid synthesis: phenylpropanoid biosynthesis genes (PAL, C4H, 4CL and CHS), flavonoid biosynthesis genes (E2.1.1.104, CHI, FLS, F3'5'H and ANR), anthocyanin biosynthesis genes (ANS, DFR, HCT, BZ1, GT1, and UGT79B1), isoflavonoid biosynthesis genes (HIDH and CYP81E17), and their transcriptional regulator (MYB). A total of 234 types of flavonoids were detected. The types and contents of anthocyanins in the red-leaf varieties 'Hong Jingling' and 'Caidie Fanfei' were significantly higher than those in the green leaf cultivar 'Lv Baoshi', especially morning glory 3-O-glucoside, delphinidin 3-O-glucoside, and pelargonium-3-O-glucoside, which were not detected in 'Lv Baoshi'. Combined omics analysis showed that downregulated expression of C4H, CHS and F3'5'H and upregulated expression of FLS reduced the supply of raw materials for anthocyanin synthesis, and downstream ANR upregulation converted anthocyanins to procyanidins, increasing the total flavonoid content. F3'5'H expression was downregulated in the leaves of each variety with development, resulting in the accumulation of catechins and the gradual greening of the leaves. F3'5'H was significantly depleted in the young leaves of 'Hong Jingling' and 'Caidie Fanfei' compared with the young leaves of 'Lv Baoshi', while ANS and BZ1 were enriched significantly. It is concluded that F3'5'H, BZ1, and ANS are the key genes needed for breeding red A. truncatum and that ANR is the key gene needed for breeding varieties with a high flavonoids contens. These results may facilitate genetic modification or selection for further improvement of the ornamental qualities and flavonoid content of A. truncatum.

The mechanisms of wine phenolic compounds for preclinical anticancer therapeutics

Background

Wine is one of the oldest and most popular drinks worldwide, which is rich in phenolic compounds. Epidemiological studies show that moderate consumption of wine can reduce the risk of certain diseases, and this effect is attributed to its phenolic compounds.

Objective

The objective of this review was to elaborate the effects of wine-derived phenolic compounds for preclinical anticancer therapeutics and their major mechanisms.

Methods

In this review, we discuss the classification and content of common phenolic compounds in wine and summarize previous studies that have evaluated the anticancer properties of wine-derived phenolic compounds and their mechanisms.

Results

Wine-derived phenolic compounds have been proven to participate in several mechanisms against cancers, including deoxyribonucleic acid damage, oxidative stress, cell proliferation, cell cycle arrest, cell apoptosis, autophagy, cell invasion and metastasis, immunity and metabolism, regulation of multiple signaling molecules, and gene expression. However, the exact anticancer mechanisms of the phenolic compounds in wine need to be further investigated.

Conclusion

Wine-derived phenolic compounds are promising chemoprotective and chemotherapeutic agents for cancer.

Dietary Assessment Methods to Estimate (Poly)phenol Intake in Epidemiological Studies: A Systematic Review

Nutritional epidemiological studies have frequently reported associations between higher (poly)phenol intake and a decrease in the risk or incidence of noncommunicable diseases. However, the assessment methods that have been used to quantify the intakes of these compounds in large-population samples are highly variable. This systematic review aims to characterize the methods used to assess dietary (poly)phenol intake in observational studies, report the validation status of the methods, and give recommendations on method selection and data reporting. Three databases were searched for publications that have used dietary assessment methods to measure (poly)phenol intake and 549 eligible full texts were identified. Food-frequency questionnaires were found to be the most commonly used tool to assess dietary (poly)phenol intake (73%). Published data from peer-reviewed journals were the major source of (poly)phenol content data (25%). An increasing number of studies used open-access databases such as Phenol-Explorer and USDA databases on flavonoid content since their inception, which accounted for 11% and 23% of the data sources, respectively. Only 16% of the studies reported a method that had been validated for measuring the target (poly)phenols. For future research we recommend: 1) selecting a validated dietary assessment tool according to the target compounds and target period of measurement; 2) applying and combining comprehensive (poly)phenol content databases such as USDA and Phenol-Explorer; 3) detailing the methods used to assess (poly)phenol intake, including dietary assessment method, (poly)phenol content data source; 4) follow the Strengthening the Reporting of Observational Studies in Epidemiology-Nutritional Epidemiology (STROBE-nut) framework; and 5) complementing dietary intake assessment based on questionnaires with measurement of (poly)phenols in biofluids using appropriate and validated analytical methods.

Polyphenol Intake and Gastric Cancer Risk: Findings from the Stomach Cancer Pooling Project (StoP)

Simple Summary

Gastric cancer (GC) has the fifth highest incidence of any cancer type worldwide and the third highest mortality rate, so its prevention is very important. Among dietary factors, the consumption of fruit and vegetables has been inversely related to GC risk. Phenolic compounds may exert a favorable effect on the risk of several cancer types, including gastric cancer. However, selected polyphenol classes have not been adequately investigated in relation to GC. There is, however, no comprehensive analysis of polyphenols and GC risk methods to date. In order to provide a detailed evaluation of the relationship between dietary intake of polyphenols and GC risk, we analyzed data from the Stomach cancer Pooling (StoP) Project consortium.

Abstract

Phenolic compounds may exert a favorable effect on the risk of several cancer types, including gastric cancer (GC). However, selected polyphenol classes have not been adequately investigated in relation to GC. The aim of this study is to evaluate the association between the intake of polyphenols in relation to GC risk. We used data from the Stomach cancer Pooling (StoP) Project, including 10 studies from six countries (3471 GC cases and 8344 controls). We carried out an individual participant data pooled analysis using a two-stage approach. The summary odds ratios (ORs) of GC for each compound, and the corresponding 95% confidence intervals (95% CI), were computed by pooling study specific ORs obtained through multivariate logistic regression, using random effect models. Inverse associations with GC emerged for total polyphenols (OR = 0.67, 95% CI = 0.54–0.81, for the highest versus lowest quartile of intake), total flavonoids (OR = 0.73, 95% CI = 0.55–0.90), anthocyanidins (OR = 0.74, 95% CI = 0.56–0.92), flavanols (OR = 0.77, 95% CI = 0.66–0.88), flavanones (OR = 0.57, 95%CI = 0.44–0.69), total phenolic acids (OR = 0.75, 95%CI = 0.55–0.94), and hydroxybenzoic acids (OR = 0.73, 95%CI = 0.57–0.89). Results were consistent across strata of age, sex, social class, and smoking habit. Suggestive inverse associations were also found for flavonols (OR = 0.76, 95%CI = 0.51–1.01) and hydroxycinnamic acids (OR = 0.82, 95%CI = 0.58–1.06). Further investigations from longitudinal data are needed to confirm this association.

Association of tea consumption and the risk of gastric cancer in Japanese adults: the Japan Collaborative Cohort Study

OBJECTIVE

To examine the possible relationship between tea consumption and risk of gastric cancer (GC) among Japanese men and women included in a large Japanese population-based study titled the Japan Collaborative Cohort (JACC) Study.

DESIGN

Prospective cohort study.

SETTING

A population-based cohort included subjects who were recruited from 24 areas of JACC Study, in which data regarding the incidence of cancer were available.

PARTICIPANTS

63 848 participants (26 025 men and 37 823 women), aged 40-79, were included in the analyses and underwent follow-up (median 13.3 years) prospectively in research on cancer incidence.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome variable was the risk of GC according to the frequency intakes of total tea, green tea, black tea and oolong tea. The adjusted HRs for the risk of GC associated with tea consumption were calculated using the Cox proportional hazards model.

RESULTS

1494 cases of GC were detected (960 men and 534 women) during the follow-up period. The multivariable-adjusted HRs for the risk of GC in the highest versus lowest quintiles of total tea intake were 1.05 (0.83-1.33); p trend=0.50 in men, and 0.82 (0.60-1.12); p trend=0.45 in women. There was no association found between the consumption of green tea, black tea or oolong tea with the risk for GC in either gender.

CONCLUSIONS

In this large community-based prospective cohort study, tea consumption was not associated with the risk of GC in either gender.

Lignans: Quantitative Analysis of the Research Literature

The current study provides a comprehensive overview and analysis of the lignan literature. Data for the current study were extracted from the electronic Web of Science Core Collection database via the search string TOPIC = ("lignan*") and processed by the VOSviewer software. The search yielded 10,742 publications. The ratio of original articles to reviews was 14.6:1. Over 80% of the analyzed papers have been published since the year 2000 and nearly 50% since the year 2010. Many of the publications were focused on pharmacology, chemistry, and plant sciences. The United States and Asian countries, such as China, Japan, South Korea, and India, were the most productive producers of lignan publications. Among the 5 most productive institutions was the University of Helsinki in Finland, the country that ranked 9^th. Nineteen journals collectively published 3,607 lignan publications and were considered as core journals. Their impact factor did not correlate with the proportion of uncited papers. Highly cited publications usually mentioned phytoestrogen, isoflavone, daidzein, enterodiol, enterolactone, equol, genistein, and isoflavonoid. Cancer (e.g., breast cancer), cardiovascular disease, and antioxidation were the major themes. Clinical trials were estimated to contribute to 0.2-1.1% of the analyzed body of literature, so more of them should be conducted in the future to substantiate the beneficial effects and optimal dose of lignan intake in humans. Moreover, researchers can refer to these findings for future research directions and collaborations.

The Role of Polyphenol (Flavonoids) Compounds in the Treatment of Cancer Cells

Cancer remains a second leading cause of deaths and major public health problem. It occurs due to extensive DNA damage caused by ultraviolet radiations, ionizing radiations, environmental agents, therapeutic agents, etc. Among all cancers, the most frequently diagnosed cancers are lung (12.7%), breast (10.9%), colorectal (9.7%), and gastric cancer (7.81%). Natural compounds are most favorable against cancer on the count of their anti-cancerous ability, easy to avail and efficient. Among natural compounds, polyphenols (flavonoids, catechin, hesperetin, flavones, quercetin, phenolic acids, ellagic acid, lignans, stilbenes, etc.) represent a large and diverse group used in the prevention and treatment of cancer. Natural flavonoids are derived from different plant sources and from various medicinal plants including Petroselinum crispum, Apium graveolens, Flemingia vestita, Phyllanthus emblica, etc. Natural flavonoids possess antioxidant, anti-inflammation, as well as anti-cancerous activities through multiple pathways, they induce apoptosis in breast, colorectal, and prostate cancers, lower the nucleoside diphosphate kinase-B activity in lung, bladder and colon cancers, inhibit cell-proliferation and cell cycle arrest by suppressing the NF-kB pathway in various cancers, etc. The current review summarized the anticancer activities of natural polyphenols and their mechanisms of action.

The NCI-N87 Cell Line as a Gastric Epithelial Model to Study Cellular Uptake, Trans-Epithelial Transport, and Gastric Anti-Inflammatory Properties of Anthocyanins

Anthocyanins are ubiquitous plant pigments with reported antioxidant, anti-inflammatory, and anti-cancer activities. To better understand these benefits, metabolism of anthocyanins requires further evaluation, especially in the stomach. Mammalian cell cultures provide useful models for investigating compound metabolism and absorption, but they are generally maintained at physiological pH. The NCI-N87 cell line is an acid-stable model of the gastric epithelium used to study gastric drug metabolism. The objective of this work was to investigate the uptake, trans-epithelial transport, and anti-inflammatory activity of anthocyanins by the NCI-N87 cell line. The cells formed a coherent monolayer, stable ≤32 days post confluency. Minimal effects on monolayer integrity were observed when the pH of the apical chamber was adjusted to pH 3.0, 5.0, or 7.4. Anthocyanins were transported across the NCI-N87 cell monolayer at 37 °C, but not at 0 °C, suggesting a facilitated process. Chokeberry anthocyanins (0-1500 μM) were not cytotoxic. At apical pH 3.0, they had anti-inflammatory properties by significantly attenuating IL-8 secretion when added to medium before, during, and after incubation with IL-1β. These results suggest that the NCI-N87 cell line is a physiologically relevant model for in vitro studies of the transport, anti-inflammatory and potential anti-carcinogenic activities of anthocyanins in gastric tissue.

Accumulation of plasma levels of anthocyanins following multiple saskatoon berry supplements

1. Anthocyanins are a subgroup of flavonoids responsible for the blue, purple and red color of many fruits, flowers and leaves. Consumption of foods rich in anthocyanins is associated with a reduced risk of cardiovascular disease and cancer. Most food intervention studies employ once or twice per day dose schedules. 2. The current study demonstrated that plasma concentrations of cyanidin-3-galactoside and cyanidin-3-xyloside, the two major components of saskatoon berries, were significantly increased following three consecutive saskatoon berry supplements 4 hours apart. This accumulation is due to the residual concentrations of anthocyanins at the time of second and third supplements. 3. Accumulation was especially pronounced for peonidin-3-glucoside and peonidin-3-galactoside, the methylated metabolites of cyanidin-3-glucoside and cyanidin-3-galactoside, respectively. Little or no accumulation was observed for cyanidin-3-arabinoside and cyanidin-3-glucoside, two other components of saskatoon berries, possibly due to their short half-lives. 4. Thus, taking anthocyanin supplements with every meal would provide higher plasma concentrations for some anthocyanins and their metabolites than the once or twice-a-day dose regimens.

Intake of Anthocyanins and Gastric Cancer Risk: A Comprehensive Meta-Analysis on Cohort and Case-Control Studies

This meta-analysis aimed to explore the association between anthocyanins intake and the risk of gastric cancer. All the relative articles have been searched in the online databases, including PubMed, EMBASE, Web of Science, and the Cochrane Library until June 11th, 2018. Risk ratios (RRs) or odds ratio (ORs) and their 95% confidence intervals were calculated and pooled through the STATA 12.0. A total of 6 studies were finally selected in the meta-analysis. No significant association was found between total anthocyanins consumption and gastric cancer risk (RR=0.92, 95%CI: 0.81-1.04). Likewise, there was also no significant evidence of the relationship between anthocyanins intake and gastric cancer in tumor site (cardia: RR=0.90, 95%CI: 0.62-1.31; noncardia: RR=0.86, 95%CI: 0.69-1.07) and gender (men: RR=1.02, 95%CI: 0.73-1.40; women: RR=0.80, 95%CI: 0.52-1.23). The dose-response relationship was also not found in this meta-analysis. The Grades of Recommendations Assessment, Development and Evaluation (GRADE) quality in our study was very low. The results of our meta-analysis suggested the intake of anthocyanins had no association with the risk of gastric cancer and further studies are needed.

Dietary Flavonoids as Cancer Chemopreventive Agents: An Updated Review of Human Studies

Over the past few years, interest in health research has increased, making improved health a global goal for 2030. The purpose of such research is to ensure healthy lives and promote wellbeing across individuals of all ages. It has been shown that nutrition plays a key role in the prevention of some chronic diseases such as obesity, cardiovascular disease, diabetes, and cancer. One of the aspects that characterises a healthy diet is a high intake of vegetables and fruits, as both are flavonoid-rich foods. Flavonoids are one of the main subclasses of dietary polyphenols and possess strong antioxidant activity and anti-carcinogenic properties. Moreover, some population-based studies have described a relationship between cancer risk and dietary flavonoid intake. In this context, the goal of this review was to provide an updated evaluation of the association between the risk of different types of cancers and dietary flavonoid intake. We analysed all relevant epidemiological studies from January 2008 to March 2019 using the PUBMED and Web of Science databases. In summary, this review concludes that dietary flavonoid intake is associated with a reduced risk of different types of cancer, such as gastric, breast, prostate, and colorectal cancers.

Flaxseed Lignans as Important Dietary Polyphenols for Cancer Prevention and Treatment: Chemistry, Pharmacokinetics, and Molecular Targets

Cancer causes considerable morbidity and mortality across the world. Socioeconomic, environmental, and lifestyle factors contribute to the increasing cancer prevalence, bespeaking a need for effective prevention and treatment strategies. Phytochemicals like plant polyphenols are generally considered to have anticancer, anti-inflammatory, antiviral, antimicrobial, and immunomodulatory effects, which explain their promotion for human health. The past several decades have contributed to a growing evidence base in the literature that demonstrate ability of polyphenols to modulate multiple targets of carcinogenesis linking models of cancer characteristics (i.e., hallmarks and nutraceutical-based targeting of cancer) via direct or indirect interaction or modulation of cellular and molecular targets. This evidence is particularly relevant for the lignans, an ubiquitous, important class of dietary polyphenols present in high levels in food sources such as flaxseed. Literature evidence on lignans suggests potential benefit in cancer prevention and treatment. This review summarizes the relevant chemical and pharmacokinetic properties of dietary polyphenols and specifically focuses on the biological targets of flaxseed lignans. The consolidation of the considerable body of data on the diverse targets of the lignans will aid continued research into their potential for use in combination with other cancer chemotherapies, utilizing flaxseed lignan-enriched natural products.

Flavonoids and the Risk of Gastric Cancer: An Exploratory Case-Control Study in the MCC-Spain Study

Several epidemiological studies have investigated the association between the dietary flavonoid intake and gastric cancer (GC) risk; however, the results remain inconclusive. Investigating the relationship between the different classes of flavonoids and the histological types and origin of GC can be of interest to the research community. We used data from a population-based multi-case control study (MCC-Spain) obtained from 12 different regions of Spain. 2700 controls and 329 GC cases were included in this study. Odds ratios (ORs) were calculated using the mixed effects logistic regression considering quartiles of flavonoid intakes and log2. Flavonoid intake was associated with a lower GC risk (ORlog2 = 0.76; 95% CI = 0.65-0.89; ORq4vsq1 = 0.60; 95%CI = 0.40-0.89; ptrend = 0.007). Inverse and statistically significant associations were observed with anthocyanidins, chalcones, dihydroflavonols and flavan-3-ols. The isoflavanoid intake was positively associated with higher cancer risk, but without reaching a statistical significance. In general, no differences were observed in the GC risk according to the location and histological type. The flavonoid intake seems to be a protective factor against GC within the MCC-study. This effect may vary depending on the flavonoid class but not by the histological type and location of the tumor. Broader studies with larger sample size and greater geographical variability are necessary.

Plant phenolics as functional food ingredients

Phenolic compounds have attracted much attention in recent times as their dietary intake has been associated with the prevention of some chronic and degenerative diseases that constitute major causes of death and incapacity in developed countries, such as cardiovascular diseases, type II diabetes, some types of cancers or neurodegenerative disorders like Alzheimer's and Parkinson's diseases. Nowadays it is considered that these compounds contribute, at least in part, for the protective effects of fruit and vegetable-rich diets, so that the study of their role in human nutrition has become a central issue in food research. This chapter reviews the current knowledge on the phenolic compounds as food components, namely their occurrence in the diet, bioavailability and metabolism, biological activities and mechanisms of action. Besides, the approaches for their extraction from plant matrices and technological improvements regarding their preparation, stability and bioavailability in order to be used as functional food ingredients are also reviewed, as well as their legal situation regarding the possibility of making "health claims" based on their presence in food and beverages.

Dietary Lignans: Definition, Description and Research Trends in Databases Development

The study aims to communicate the current status regarding the development and management of the databases on dietary lignans; within the phytochemicals, the class of the lignan compounds is of increasing interest because of their potential beneficial properties, i.e., anticancerogenic, antioxidant, estrogenic, and antiestrogenic activities. Furthermore, an introductory overview of the main characteristics of the lignans is described here. In addition to the importance of the general databases, the role and function of a food composition database is explained. The occurrence of lignans in food groups is described; the initial construction of the first lignan databases and their inclusion in harmonized databases at national and/or European level is presented. In this context, some examples of utilization of specific databases to evaluate the intake of lignans are reported and described.

Anti‑cancer effects of fisetin on mammary carcinoma cells via regulation of the PI3K/Akt/mTOR pathway: In vitro and in vivo studies

Fisetin, a natural flavonoid found in a variety of edible and medical plants, has been suggested to inhibit the proliferation of various tumor cells and to induce apoptosis. However, the effects of fisetin on breast cancer have rarely been reported and the underlying mechanism is still undefined. The present study explored the anti‑cancer effects of fisetin on mammary carcinoma cells and the underlying mechanisms. Following treatment with fisetin, viability of 4T1, MCF‑7 and MDA‑MB‑231 cells were measured by MTT assay. The inhibitory effects of fisetin on proliferation, migration and invasion were evaluated in 4T1 cells using proliferation array, wound‑healing assay, and HUV‑EC‑C‑cell barrier based on electrical cell‑substrate impedance sensing platform. Cell apoptosis was analyzed by flow cytometry, and western blotting analysis was performed to identify target molecules. A 4T1 orthotopic mammary tumor model was used to assess the fisetin‑inhibition on tumor growth in vivo. Test kits were used to examine the liver and kidney function of tumor‑bearing mice. The results suggest that fisetin suppressed the proliferation of breast cancer cells, suppressed the metastasis and invasiveness of 4T1 cells, and induced the apoptosis of 4T1 cells in vitro. The potent anti‑cancer effect of fisetin was associated with the regulation of the phosphatidylinositol‑3‑kinase/protein kinase B/mammalian target of rapamycin pathway. In vivo experiments demonstrated that fisetin suppressed the growth of 4T1 cell‑derived orthotopic breast tumors and enhanced tumor cell apoptosis, and the evaluated alanine amino transferase and aspartate amino transferase levels in serum of tumor‑bearing mice suggested that fisetin may lead to side effects on liver biochemical function. The present study confirms that fisetin exerted an anti‑mammary carcinoma effect. However, in vivo experiments also revealed that fisetin had low solubility and low bioavailability. Further investigation is required to determine the clinical value of fisetin.

The association between dietary isoflavones intake and gastric cancer risk: a meta-analysis of epidemiological studies

Background

Isoflavones, a class of phytoestrogenic compounds, are abundant in soybeans. A number of epidemiological studies have investigated the association between dietary isoflavones intake and the risk of gastric cancer. However, the results are inconclusive. Therefore, the meta-analysis was conducted to evaluate the effect of dietary isoflavones intake on the risk of gastric cancer.

Methods

Relevant studies from May 1992 to May 2017 were identified through searching PubMed and Web of Science. Additional articles were identified from the reference lists of relevant review articles. Pooled risk ratios (RRs) or odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a fixed-effects model. Funnel plot and Egger’s test were used to evaluate publication bias.

Results

Seven articles reporting 12 studies were included in the current meta-analysis. We found no significant association between dietary isoflavones intake and gastric cancer risk with the highest versus the lowest categories of dietary isoflavones intake (OR = 0.97, 95% CI = 0.87–1.09, I² = 27.5%). Subgroup analyses generally yield similar results.

Conclusions

Higher dietary isoflavones intake is not associated with a decline in the risk of gastric cancer.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5424-7) contains supplementary material, which is available to authorized users.

Inflammatory potential of the diet and risk of gastric cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) study

Background

Chronic inflammation plays a critical role in the pathogenesis of the 2 major types of gastric cancer. Several foods, nutrients, and nonnutrient food components seem to be involved in the regulation of chronic inflammation.

Objective

We assessed the association between the inflammatory potential of the diet and the risk of gastric carcinoma, overall and for the 2 major subsites: cardia cancers and noncardia cancers.

Design

A total of 476,160 subjects (30% men, 70% women) from the European Investigation into Cancer and Nutrition (EPIC) study were followed for 14 y, during which 913 incident cases of gastric carcinoma were identified, including 236 located in the cardia, 341 in the distal part of the stomach (noncardia), and 336 with overlapping or unknown tumor site. The dietary inflammatory potential was assessed by means of an inflammatory score of the diet (ISD), calculated with the use of 28 dietary components and their corresponding inflammatory scores. The association between the ISD and gastric cancer risk was estimated by HRs and 95% CIs calculated by multivariate Cox regression models adjusted for confounders.

Results

The inflammatory potential of the diet was associated with an increased risk of gastric cancer. The HR (95% CI) for each increase in 1 SD of the ISD were 1.25 (1.12, 1.39) for all gastric cancers, 1.30 (1.06, 1.59) for cardia cancers, and 1.07 (0.89, 1.28) for noncardia cancers. The corresponding values for the highest compared with the lowest quartiles of the ISD were 1.66 (1.26, 2.20), 1.94 (1.14, 3.30), and 1.07 (0.70, 1.70), respectively.

Conclusions

Our results suggest that low-grade chronic inflammation induced by the diet may be associated with gastric cancer risk. This pattern seems to be more consistent for gastric carcinomas located in the cardia than for those located in the distal stomach. This study is listed on the ISRCTN registry as ISRCTN12136108.

Flavan-3-ols consumption and cancer risk: A meta-analysis of epidemiologic studies

Although numerous in vitro studies and animal model data have suggested that flavan-3-ols, the most common subclass of flavonoids in the diet, may exert protective effects against cancer, epidemiologic studies have reported inconclusive results for the association between flavan-3-ols intake and cancer risk. Therefore, we conducted this meta-analysis of epidemiologic studies to investigate the preventive effects of flavan-3-ols on various types of cancers. A total of 43 epidemiologic studies, consisting of 25 case-control and 18 prospective cohort studies, were included. A significant inverse association was shown between flavan-3-ols intake and the risk of overall cancer (relative risk (RR) 0.935, 95%CI: 0.891-0.981). When cancer types were separately analyzed, a statistically significant protective effect of flavan-3-ols consumption was observed in rectal cancer (RR 0.838, 95%CI: 0.733-0.958), oropharyngeal and laryngeal cancer (RR 0.759, 95%CI: 0.581-0.993), breast (RR 0.885, 95%CI: 0.790-0.991) in case-control studies and stomach cancer in women (RR 0.633, 95%CI: 0.468-0.858). Our analysis indicates the potential benefits of flavan-3-ols in cancer prevention.

Intake of Individual Flavonoids and Risk of Carcinogenesis: Overview of Epidemiological Evidence

Several epidemiological findings have demonstrated that specific flavonoids can be responsible for reduction of the risk of certain cancer types. However, these results are still rather limited, inconclusive and controversial. Therefore, in this comprehensive review article the findings reported to date about the associations between dietary intake of individual flavonoid compounds and cancer incidence are compiled and analyzed. Also, the possible reasons for inconsistencies are brought forth and discussed. As diet is a potentially modifiable factor in our behavioral choices, further large-scale prospective studies with longer follow-up times, different populations, various doses and exposure timing as well as diverse well-controlled confounders are highly needed to confirm or disprove the current epidemiological knowledge about the role of flavonoids on cancer risk. Regarding the promising data to date, more research on bioavailability, metabolism and biological action mechanisms of these plant secondary metabolites is also encouraged.

Dietary Flavonoid Intake Reduces the Risk of Head and Neck but Not Esophageal or Gastric Cancer in US Men and Women

Background: Flavonoids are bioactive polyphenolic compounds found in fruits, vegetables, and beverages of plant origin. Previous studies have shown that flavonoid intake reduces the risk of certain cancers; however, few studies to date have examined associations of flavonoids with upper gastrointestinal cancers or used prospective cohorts.Objective: Our study examined the association between intake of flavonoids (anthocyanidins, flavan-3-ols, flavanones, flavones, flavonols, and isoflavones) and risk of head and neck, esophageal, and gastric cancers.Methods: The NIH-AARP Diet and Health Study is a prospective cohort study that consists of 469,008 participants. Over a mean 12-y follow-up, 2453 head and neck (including 1078 oral cavity, 424 pharyngeal, and 817 laryngeal), 1165 esophageal (890 adenocarcinoma and 275 squamous cell carcinoma), and 1297 gastric (625 cardia and 672 noncardia) cancer cases were identified. We used Cox proportional hazards regression models to estimate HRs and CIs for the associations between flavonoid intake assessed at study baseline and cancer outcomes. For 56 hypotheses examined, P-trend values were adjusted using the Benjamini-Hochberg (BH) procedure for false discovery rate control.Results: The highest quintile of total flavonoid intake was associated with a 24% lower risk of head and neck cancer (HR: 0.76; 95% CI: 0.66, 0.86; BH-adjusted 95% CI: 0.63, 0.91; P-trend = 0.02) compared with the lowest quintile. Notably, anthocyanidins were associated with a 28% lower risk of head and neck cancer (HR: 0.72; 95% CI: 0.62, 0.82; BH-adjusted 95% CI: 0.59, 0.87; P-trend = 0.0005), and flavanones were associated with a 22% lower risk of head and neck cancer (HR: 0.78; 95% CI: 0.68, 0.89; BH-adjusted 95% CI: 0.64, 0.94; P-trend: 0.02). No associations between flavonoid intake and risk of esophageal or gastric cancers were found.Conclusions: Our results indicate that flavonoid intake is associated with lower head and neck cancer risk. These associations suggest a protective effect of dietary flavonoids on head and neck cancer risk, and thus potential as a risk reduction strategy.

Dietary Flavonoid and Lignan Intake and Mortality in Prospective Cohort Studies: Systematic Review and Dose-Response Meta-Analysis

Recent evidence has suggested that flavonoid and lignan intake may be associated with decreased risk of chronic and degenerative diseases. The aim of this meta-analysis was to assess the association between dietary flavonoid and lignan intake and all-cause and cardiovascular disease (CVD) mortality in prospective cohort studies. A systematic search was conducted in electronic databases to identify studies published from January 1996 to December 2015 that satisfied inclusion/exclusion criteria. Risk ratios and 95% confidence intervals were extracted and analyzed using a random-effects model. Nonlinear dose-response analysis was modeled by using restricted cubic splines. The inclusion criteria were met by 22 prospective studies exploring various flavonoid and lignan classes. Compared with lower intake, high consumption of total flavonoids was associated with decreased risk of all-cause mortality (risk ratio = 0.74, 95% confidence intervals: 0.55, 0.99), while a 100-mg/day increment in intake led to a (linear) decreased risk of 6% and 4% of all-cause and CVD mortality, respectively. Among flavonoid classes, significant results were obtained for intakes of flavonols, flavones, flavanones, anthocyanidins, and proanthocyanidins. Only limited evidence was available on flavonoid classes and lignans and all-cause mortality. Findings from this meta-analysis indicated that dietary flavonoids are associated with decreased risk of all-cause and CVD mortality.

Dietary flavonoid intake and colorectal cancer risk in the European prospective investigation into cancer and nutrition (EPIC) cohort

Flavonoids have been shown to inhibit colon cancer cell proliferation in vitro and protect against colorectal carcinogenesis in animal models. However, epidemiological evidence on the potential role of flavonoid intake in colorectal cancer (CRC) development remains sparse and inconsistent. We evaluated the association between dietary intakes of total flavonoids and their subclasses and risk of development of CRC, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. A cohort of 477,312 adult men and women were recruited in 10 European countries. At baseline, dietary intakes of total flavonoids and individual subclasses were estimated using centre-specific validated dietary questionnaires and composition data from the Phenol-Explorer database. During an average of 11 years of follow-up, 4,517 new cases of primary CRC were identified, of which 2,869 were colon (proximal = 1,298 and distal = 1,266) and 1,648 rectal tumours. No association was found between total flavonoid intake and the risk of overall CRC (HR for comparison of extreme quintiles 1.05, 95% CI 0.93-1.18; p-trend = 0.58) or any CRC subtype. No association was also observed with any intake of individual flavonoid subclasses. Similar results were observed for flavonoid intake expressed as glycosides or aglycone equivalents. Intake of total flavonoids and flavonoid subclasses, as estimated from dietary questionnaires, did not show any association with risk of CRC development.

A Review of the Antiviral Properties of Black Elder (Sambucus nigra L.) Products

Black elder (Sambucus nigra L.) has a long ethnobotanical history across many disparate cultures as a treatment for viral infection and is currently one of the most-used medicinal plants worldwide. Until recently, however, substantial scientific research concerning its antiviral properties has been lacking. Here, we evaluate the state of current scientific research concerning the use of elderberry extract and related products as antivirals, particularly in the treatment of influenza, as well as their safety and health impacts as dietary supplements. While the extent of black elder's antiviral effects are not well known, antiviral and antimicrobial properties have been demonstrated in these extracts, and the safety of black elder is reflected by the United States Food and Drug Administration approval as generally recognized as safe. A deficit of studies comparing these S. nigra products and standard antiviral medications makes informed and detailed recommendations for use of S. nigra extracts in medical applications currently impractical. Copyright © 2017 John Wiley & Sons, Ltd.

Cereal Lignans, Natural Compounds of Interest for Human Health?

Cereals are suggested to be the most important sources of lignan in the diets of western populations. Recent epidemiological studies show that European subpopulations in which the major source of lignans are cereals, display lower disease frequency regarding metabolic and cardiovascular diseases. The biological mechanisms of lignan are several. Beyond their antioxidant and anti-inflammatory actions at nutritional doses some lignans regulate the activity of specific nuclear receptors (NRs), such as the estrogen receptors (ERs), and also NRs that are central switches in glucose and fatty acid metabolism such as PPARα, PPARγ and LXRs, highlighting them as selective nuclear receptor modulators (SNRMs). These include enterodiol (END) and enterolactone (ENL), the metabolites produced by the gut microbiota from food lignans. The available knowledge suggests that given some additional research it should be possible to make ‘function' claims for a regular intake of lignans-rich foods related to maintaining a healthy metabolism.

Lychee pulp phenolics ameliorate hepatic lipid accumulation by reducing miR-33 and miR-122 expression in mice fed a high-fat diet

The repression of miR-33 and miR-122 is a possible molecular mechanism of the hypolipidemic effects of lychee pulp phenolics.

Estimated dietary intake and major food sources of polyphenols in elderly of Viçosa, Brazil: a population-based study

PURPOSE

Epidemiological studies have remarked the beneficial role that polyphenols may have in the elderly population such as cancer and cardiovascular disease prevention. This is particularly relevant considering the global tendency of population aging. Data on polyphenol intake in the elderly population are scarce and usually provide partial information-only for some polyphenol classes. The aim of this study was to estimate the intake of polyphenols and its major dietary contributors in the population of Viçosa.

METHODS

A cross-sectional population-based survey including 620 elderly was conducted in Viçosa, Brazil. Food intake was estimated by recall of habitual consumption (RHC). Polyphenol intake was calculated by matching food consumption data from the RHC with the polyphenol content in foods listed in the Phenol-Explorer database.

RESULTS

The average total polyphenol intake was 1198.6 mg/day (533.7 mg/day as aglycone). The main polyphenol classes were phenolic acids (729.5 mg/day) and flavonoids (444.7 mg/day). The main dietary contributors for total polyphenols were coffee (45.8%), beans (32.8%) and polenta (1.3%). A total of 292 polyphenols divided in 14 classes and 23 subclasses were found. The individual compounds with the highest intake were isomers of chlorogenic acid (i.e., 5-caffeoylquinic acid, 4-caffeoylquinic acid and 3-caffeoylquinic acid) among hydroxycinnamic acids that largely originated from coffee.

CONCLUSIONS

The data reported here can be used to evaluate the association between the amount and type of ingested polyphenols and health outcomes in epidemiological studies in order to eventually establish nutritional recommendations.

The anthocyanin cyanidin-3-O-β-glucoside modulates murine glutathione homeostasis in a manner dependent on genetic background

Anthocyanins are a class of phytochemicals that have generated considerable interest due to their reported health benefits. It has been proposed that commonly consumed anthocyanins, such as cyandin-3-O-β-glucoside (C3G), confer cellular protection by stimulating biosynthesis of glutathione (GSH), an endogenous antioxidant. Currently, it is unknown whether the health effects of dietary anthocyanins are genetically determined. We therefore tested the hypothesis that anthocyanin-induced alterations in GSH homeostasis vary by genetic background. Mice representing five genetically diverse inbred strains (A/J, 129S1/SvImJ, CAST/EiJ, C57BL/6J, and NOD/ShiLtJ) were assigned to a control or 100mg/kg C3G diet (n=5/diet/strain) for six weeks. GSH and GSSG levels were quantified in liver, kidney, heart, pancreas, and brain samples using HPLC. The C3G diet promoted an increase in renal GSH concentrations, hepatic GSH/GSSG, and cardiac GSH/GSSG in CAST/EiJ mice. C3G treatment also induced an increase in pancreatic GSH/GSSG in C57BL/6J mice. In contrast, C3G did not affect GSH homeostasis in NOD/ShiLtJ mice. Surprisingly, the C3G-diet caused a decrease in hepatic GSH/GSSG in A/J and 129S1/SvImJ mice compared to controls; C3G-treated 129S1/SvImJ mice also exhibited lower total glutathione in the heart. Overall, we discovered that C3G modulates the GSH system in a strain- and tissue-specific manner. To our knowledge, this study is the first to show that the redox effects of anthocyanins are determined by genetic background.

Natural Polyphenols for Prevention and Treatment of Cancer

There is much epidemiological evidence that a diet rich in fruits and vegetables could lower the risk of certain cancers. The effect has been attributed, in part, to natural polyphenols. Besides, numerous studies have demonstrated that natural polyphenols could be used for the prevention and treatment of cancer. Potential mechanisms included antioxidant, anti-inflammation as well as the modulation of multiple molecular events involved in carcinogenesis. The current review summarized the anticancer efficacy of major polyphenol classes (flavonoids, phenolic acids, lignans and stilbenes) and discussed the potential mechanisms of action, which were based on epidemiological, in vitro, in vivo and clinical studies within the past five years.

Dietary flavonoid intake and the risk of digestive tract cancers: a systematic review and meta-analysis

Several epidemiological studies have investigated the association between dietary flavonoid intake and digestive tract cancers risk; however, the results remain inconclusive. The aim of our study was to evaluate this association. PubMed and the Web of Knowledge were searched for relevant publications from inception to October 2015. The risk ratio (RR) or odds ratio (OR) with the 95% confidence interval (95% CI) for the highest versus the lowest categories of flavonoid intake were pooled using a fixed-effects model. A total of 15 articles reporting 23 studies were selected for the meta-analysis. In a comparison of the highest versus the lowest categories of dietary flavonoid intake, we found no significant association between flavonoid intake and oesophageal cancer (OR = 0.91, 95% CI = 0.75–1.10; I² = 0.0%), colorectal cancer (OR = 1.02, 95% CI = 0.92–1.14, I² = 36.2%) or gastric cancer (OR = 0.88; 95% CI = 0.74–1.04, I² = 63.6%). The subgroup analysis indicated an association between higher flavonoid intake and a decreased risk of gastric cancer in the European population (OR = 0.78, 95% CI = 0.62–0.97). In conclusion, the results of this meta-analysis do not strongly support an association between dietary flavonoid intake and oesophageal or colorectal cancer. Furthermore, the subgroup analysis suggested an association between higher dietary flavonoid intake and decreased gastric cancer risk in European population.

Dietary Flavonols Intake and Risk of Esophageal and Gastric Cancer: A Meta-Analysis of Epidemiological Studies

Background: Esophageal cancer (EC) and gastric cancer (GC) are common cancers and leading causes of cancer deaths worldwide. Many studies have investigated the association between dietary flavonols intake and the risk of EC and GC, but the results are inconsistent. Hence, we conducted a systematic analysis of relevant population-based studies to assess the association and derive a more precise estimation. Methods: The Cochrane, PubMed and Embase databases were searched to identify articles published through January 2016 that met the predetermined inclusion criterion. Twelve studies involving 4593 patients and 519,378 controls were included. Results: The summary odds ratios (ORs) of EC, GC and the two combined were respectively 0.88 (95% CI: 0.73–1.08), 0.80 (95% CI: 0.70–0.91) and 0.83 (95% CI: 0.74–0.92) for the highest category of dietary flavonols intake compared with the lowest. No significant heterogeneities were observed in these studies. Further analysis showed that the pooled ORs of EC and GC for cohort, population-based case-control and hospital-based case-control studies were 0.90 (95% CI: 0.61–1.34), 0.92 (95% CI: 0.72–1.18), 0.68 (95% CI: 0.38–1.24) and 0.83 (95% CI: 0.65–1.06), 0.84 (95% CI: 0.45–1.59), 0.70 (95% CI: 0.56–0.88). The subgroup analyses revealed a significant association of flavonol intake with a reduced risk of noncardia gastric adenocarcinoma but not gastric cardia adenocarcinoma. Moreover, significant inverse associations of flavonol intake with GC risk were observed in women but not in men, in smokers but not in nonsmokers, in European populations but not in American populations. Similarly, a significant inverse association of flavonols intake with EC risk was also observed in smokers but not in nonsmokers. Conclusion: High intake of dietary flavonols is significantly related to a reduced risk of GC, especially in women and smokers.

Date (Phoenix dactylifera) Polyphenolics and Other Bioactive Compounds: A Traditional Islamic Remedy's Potential in Prevention of Cell Damage, Cancer Therapeutics and Beyond

This review analyzes current studies of the therapeutic effects of Phoenix dactylifera, or date palm fruit, on the physiologic system. Specifically, we sought to summarize the effects of its application in preventing cell damage, improving cancer therapeutics and reducing damage caused by conventional chemotherapy. Phoenix dactylifera exhibits potent anti-oxidative properties both in vitro and in vivo. This allows the fruit to prevent depletion of intrinsic protection from oxidative cell damage and assist these defense systems in reducing cell damage. Macroscopically, this mechanism may be relevant to the prevention of various adverse drug events common to chemotherapy including hepatotoxicity, nephrotoxicity, gastrotoxicity, and peripheral neuropathy. While such effects have only been studied in small animal systems, research suggests a potential application to more complex mammalian systems and perhaps a solution to some problems of chemotherapy in hepato-compromised and nephro-compromised patients.

Estimated Dietary Polyphenol Intake and Major Food and Beverage Sources among Elderly Japanese

Estimating polyphenol intake contributes to the understanding of polyphenols' health benefits. However, information about human polyphenol intake is scarce, especially in the elderly. This study aimed to estimate the dietary intake and major sources of polyphenols and to determine whether there is any relationship between polyphenol intake and micronutrient intake in healthy elderly Japanese. First, 610 subjects (569 men, 41 women; aged 67.3 ± 6.1 years) completed food frequency questionnaires. We then calculated their total polyphenol intake using our polyphenol content database. Their average total polyphenol intake was 1492 ± 665 mg/day, the greatest part of which was provided by beverages (79.1%). The daily polyphenol intake differed largely among individuals (183-4854 mg/day), also attributable mostly to beverage consumption. Coffee (43.2%) and green tea (26.6%) were the major sources of total polyphenol; the top 20 food items accounted for >90%. The polyphenol intake did not strongly correlate with the intake of any micronutrient, suggesting that polyphenols may exert health benefits independently of nutritional intake. The polyphenol intake in this elderly population was slightly higher than previous data in Japanese adults, and beverages such as coffee and green tea contributed highly to the intake.

Towards curative therapy in gastric cancer: Faraway, so close!

Although recent diagnostic and therapeutic advances have substantially improved the survival of patients with gastric cancer (GC), the overall prognosis is still poor. Surgery is the only curative treatment and should be performed in experienced centers. Due to high relapse following surgery, complementary and systemic treatment aimed at eradicating micrometastasis should be performed in most cases. Cytotoxic treatments are effective in downstaging locally advanced cancer, but different sensitivities and toxicities probably exist in different GC subtypes. Current treatment protocols are based primarily on clinical data and histological features, but molecular biomarkers that would allow for the prediction of treatment responses are urgently needed. Understanding how host factors are responsible for inter-individual variability of drug response or toxicity will also contribute to the development of more effective and less toxic treatments.

Dietary flavonoid intake and cardiovascular risk: a population-based cohort study

Background

The cardio-protective effects of flavonoids are still controversial; many studies referred to the benefits of specific foods, such as soy, cocoa, tea. A population-based cohort of middle-aged adults, coming from a semi-rural area where the consumption of those foods is almost negligible, was studied.

Aims

The primary objective was establishing if flavonoid intake was inversely associated with the cardiovascular (CV) risk evaluated after 12-year follow-up; the associations between flavonoid intake and CV incidence and mortality and all-cause mortality were also evaluated.

Methods

In 2001–2003, a cohort of 1,658 individuals completed a validated food-frequency questionnaire. Anthropometric, laboratory measurements, medical history and the vital status were collected at baseline and during 2014. The CV risk was estimated with the Framingham risk score.

Results

Individuals with the lowest tertile of flavonoid intake showed a worse metabolic pattern and less healthy lifestyle habits. The 2014 CV risk score and the increase in the risk score from baseline were significantly higher with the lowest intake of total and all subclasses of flavonoids, but isoflavones, in a multiple regression model. During follow-up, 125 CV events and 220 deaths (84 of which due to CV causes) occurred. CV non-fatal events were less frequent in individuals with higher flavonoid intake (HR = 0.64; 95%CI 0.42–1.00 and HR = 0.46; 95%CI 0.28–0.75 for the second and third tertiles, respectively) in Cox-regression models, after multiple adjustments. All subclasses of flavonoids, but flavones and isoflavones, were inversely correlated with incident CV events, with HRs ranging from 0.42 (flavan-3-ols) to 0.56 (anthocyanidins). Being in the third tertile of flavan-3-ols (HR = 0.68; 95% CI 0.48–0.96), anthocyanidins (HR = 0.66; 95% CI 0.46–0.95) and flavanones (HR = 0.59; 95% CI 0.40–0.85) was inversely associated with all-cause mortality. Total and subclasses of flavonoids were not significantly associated with the risk of CV mortality.

Conclusions

Flavonoid intake was inversely associated with CV risk, CV non-fatal events and all-cause mortality in a cohort with a low consumption of soy, tea and cocoa, which are typically viewed as the foods responsible for flavonoid-related benefits.

Process of formulating USDA's Expanded Flavonoid Database for the Assessment of Dietary intakes: a new tool for epidemiological research

The scientific community continues to be interested in potential links between flavonoid intakes and beneficial health effects associated with certain chronic diseases such as CVD, some cancers and type 2 diabetes. Three separate flavonoid databases (Flavonoids, Isoflavones and Proanthocyanidins) developed by the USDA Agricultural Research Service since 1999 with frequent updates have been used to estimate dietary flavonoid intakes, and investigate their health effects. However, each of these databases contains only a limited number of foods. The USDA has constructed a new Expanded Flavonoids Database for approximately 2900 commonly consumed foods, using analytical values from their existing flavonoid databases (Flavonoid Release 3.1 and Isoflavone Release 2.0) as the foundation to calculate values for all the twenty-nine flavonoid compounds included in these two databases. Thus, the new database provides full flavonoid profiles for twenty-nine predominant dietary flavonoid compounds for every food in the database. Original analytical values in Flavonoid Release 3.1 and Isoflavone Release 2.0 for corresponding foods were retained in the newly constructed database. Proanthocyanidins are not included in the expanded database. The process of formulating the new database includes various calculation techniques. This article describes the process of populating values for the twenty-nine flavonoid compounds for every food in the dataset, along with challenges encountered and resolutions suggested. The new expanded flavonoid database released on the Nutrient Data Laboratory's website would provide uniformity in estimations of flavonoid content in foods and will be a valuable tool for epidemiological studies to assess dietary intakes.