A Systematic Review of the Cardiometabolic Benefits of Plant Products Containing Mixed Phenolics and Polyphenols in Postmenopausal Women: Insufficient Evidence for Recommendations to This Specific Population.

Menopause is characterized by endocrine and physiological changes and is often accompanied by increased body weight and cholesterol, glucose intolerance, and/or hypertension. These alterations are associated with increased risk for cardiovascular diseases (CVDs) and Type II diabetes mellitus (T2DM) that may be moderate by dietary plant phenolic compounds. In this review, we examine the current evidence of the impact of a variety of plant products (foods, extracts, beverages) rich in a mixture of phenolics and polyphenols on: (i) glucose and insulin levels; (ii) lipid profile; (iii) blood pressure; and (iv) biomarkers of inflammation and oxidative stress in postmenopausal women. We critically evaluate both the results of a range of intervention studies conducted in this specific subpopulation and the level of evidence supporting the benefits of consuming those products after the menopause. Overall, the current available evidence does not allow for specific dietary recommendations of these plant products rich in phenolics and polyphenols in this high-risk subpopulation. Our data show rather variable and small effects of the different products examined on the cardiometabolic biomarkers and further support the need to: (1) improve the quality of the study designs and data reporting; and (2) understand the variability in the response of the different biomarkers and establish clear differences between healthy and cardiometabolic disease levels.

[Influence of dietary carotenoids on biomarkers of cardiometabolic risk in peri- and post-menopausal women]. / Influencia de los carotenoides sobre los marcadores de riesgo cardiometabólico en mujeres peri y posmenopáusicas.

INTRODUCTION: Background: peri- and post-menopausal women exhibit a high tendency towards obesity and visceral fat deposition, which increases cardiometabolic risk. Objective: to evaluate through a prospective nutritional study the effect of carotenoid consumption on cardiometabolic risk biomarkers in peri- and post-menopausal women. Material and methods: twelve peri- and post-menopausal women without previous symptoms of cardiovascular disease, but with some cardiometabolic risk factor, were recruited. Their diet was supplemented during 4 weeks with orange-carrot juice, tomato juice, and boiled spinach, providing 415 mg of total carotenoids/week (carotenes, cryptoxanthin, lycopene, and lutein + zeaxanthin). At the beginning (TI) and at the end (TF) of the intervention period blood samples were drawn to measure biochemical parameters, oxidative stress, inflammation and endothelial function biomarkers, and plasma carotenoid levels. Results: at TF a significant decrease (p < 0.05) in LDL-cholesterol and atherogenic index, and an increase in HDL-cholesterol were observed. Plasma carotenoids increased significantly (p < 0.05) from 0.56 µg/mL at TI to 1.22 µg/mL at TF. Concurrently, a shift in oxidative stress and inflammation biomarkers was detected, with a decrease in plasma C-reactive protein and malonaldehyde levels, and an increase in adiponectin. However, endothelial dysfunction biomarkers (sVCAM and sICAM) and total antioxidant capacity remained unchanged. Conclusions: dietary supplementation with carotenoids leads to an increase in plasma carotenoids, a decrease in atherogenic dyslipidemia, and an improvement in oxidative stress and inflammation biomarkers, which indicates a reduction in cardiometabolic risk.

INTRODUCCIÓN: Introducción: durante la menopausia hay una mayor tendencia a la obesidad y el depósito de grasa visceral, aumentando el riesgo cardiometabólico. Objetivos: evaluar mediante un estudio de intervención el efecto del consumo de carotenoides sobre los biomarcadores relacionados con el riesgo cardiometabólico en mujeres peri y posmenopáusicas. Métodos: se seleccionaron 12 mujeres peri y posmenopáusicas, sin antecedentes de enfermedad cardiovascular pero con algún factor de riesgo cardiometabólico. Durante 4 semanas se suplementó su dieta con zumo de naranja-zanahoria, zumo de tomate y espinacas cocidas, proporcionando una ingesta de 415 mg de carotenoides totales a la semana (carotenos, criptoxantina, licopeno y luteína + zeaxantina). En el momento inicial (TI) y en el final (TF) se midieron los parámetros antropométricos y se analizaron los parámetros bioquímicos, los carotenoides plasmáticos y los biomarcadores de estrés oxidativo, de inflamación y de función endotelial. Resultados: en el TF se observaron cambios significativos, disminuyendo el colesterol unido a LDL y el índice aterogénico, y aumentando el colesterol-HDL. Los carotenoides plasmáticos se incrementaron significativamente (p < 0,05) de 0,56 µg/ml en el TI hasta 1,22 µg/ml en el TF. Paralelamente se observaron cambios significativos (p < 0,05) en los biomarcadores de estrés oxidativo e inflamación, disminuyendo la proteína C-reactiva y el malonaldehído, y aumentando la adiponectina. Por el contrario, los biomarcadores de daño endotelial (sVCAM y sICAM) y la capacidad antioxidante (ORAC) no mostraron cambios tras la intervención. Conclusiones: el consumo de carotenoides aumenta los niveles plasmáticos de carotenoides y disminuye la dislipemia aterogénica, y mejora los biomarcadores de inflamación y el estrés oxidativo, lo que está relacionado con una disminución del riesgo cardiometabólico.

Ameliorative Effect of Spinach on Non-Alcoholic Fatty Liver Disease Induced in Rats by a High-Fat Diet.

The purpose of this work was to evaluate the effect of dietary carotenoids from spinach on the inflammation and oxidative stress biomarkers, liver lipid profile, and liver transcriptomic and metabolomics profiles in Sprague-Dawley rats with steatosis induced by a high-fat diet. Two concentrations of spinach powder (2.5 and 5%) were used in two types of diet: high-fat (H) and standard (N). Although rats fed diet H showed an accumulation of fat in hepatocytes, they did not show differences in the values of adiponectin, tumor necrosis factor alpha (TNF-α), and oxygen radical absorption (ORAC) in plasma or of isoprostanes in urine compared with animals fed diet N. The consumption of spinach and the accumulation of α and ß carotenes and lutein in the liver was inversely correlated with serum total cholesterol and glucose and the content of hepatic cholesterol, increasing monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and reducing cholesterol in the livers of rats fed diet H and spinach. In addition, changes in the expression of genes related to the fatty liver condition occurred, and the expression of genes involved in the metabolism of fatty acids and cholesterol increased, mainly through the overexpression of peroxisome proliferator activated receptors (PPARs). Related to liver metabolites, animals fed with diet H showed hypoaminoacidemia, mainly for the glucogenic aminoacids. Although no changes were observed in inflammation and oxidative stress biomarkers, the consumption of spinach modulated the lipid metabolism in liver, which must be taken into consideration during the dietary treatment of steatosis.

Tomato Juice Supplementation Influences the Gene Expression Related to Steatosis in Rats.

The objective of this work was to identify the effect of tomato juice on the expression of genes and levels of metabolites related to steatosis in rats. Male Sprague Dawley rats (8 weeks-old) were grouped (6 rats/group) in four experimental groups: NA (normal diet and water), NL (normal diet and tomato juice), HA (high-fat diet and water), and HL (high-fat diet and tomato juice). After an intervention period of 5 weeks, rats were sacrificed and biochemical parameters, biomarkers of oxidative stress, liver metabolites, and gene expression were determined. Although the H diet provoked dislipemia related to steatosis, no changes in isoprostanes or liver malondialdehyde (MDA) were observed. Changes in the gene expression of the HA group were produced by the high consumption of fat, whereas the consumption of tomato juice had different effects, depending on the diet. In the NL group, the genes involved in ß-oxidation were upregulated, and in groups NL and HL upregulation of CD36 and downregulation of APOB and LPL were observed. In addition, in the HL group the accumulation of lycopene upregulated the genes FXR and HNF4A, which have been suggested as preventive factors in relation to steatosis. Regarding the metabolomics study, intake of tomato juice stimulated the biosynthesis of glutathione and amino acids of the transulfurization pathway, increasing the levels of metabolites related to the antioxidant response.

Chemical composition of the edible flowers, pansy (Viola wittrockiana) and snapdragon (Antirrhinum majus) as new sources of bioactive compounds.

The nutritional composition - including total and individual phenolic compounds, carotenoids, and the antioxidant capacity - of two commercially available edible flowers, pansy and snapdragon, was studied. The edible flowers did not differ in their carbohydrates, fat, or ash contents, or in total energy, but pansy had higher values of moisture, protein, and total dietary fiber than snapdragon. Phenolic compounds were more abundant in pansy than in snapdragon, and flavonoids were the major compounds, followed by anthocyanins. The phenolic profile of pansy included flavonols, such as quercetin and isorhamnetin glycosides, flavones, such as apigenin glycosides, and anthocyanins, such as cyanidin and delphinidin glycosides; in snapdragon it included flavonol glycosides (e.g. quercetin and kaempferol glycosides) and anthocyanins, such as cyanidin and pelargonidin glycosides. The contents of total carotenoids were 146 and 29 µg/mg for pansy and snapdragon, respectively, and lutein was the dominant compound.

The effect of tomato juice supplementation on biomarkers and gene expression related to lipid metabolism in rats with induced hepatic steatosis.

PURPOSE: Tomato products are a dietary source of natural antioxidants, especially lycopene, which accumulates in the liver, where it exerts biological effects. Taking into consideration this fact, the aim of the present study was to ascertain the effect of tomato consumption on biomarkers and gene expression related to lipid metabolism in rats with induced steatosis. METHODS: Adult male Sprague-Dawley rats (8 weeks old) were randomly grouped (n = 6 rats/group) in four experimental groups: NA (normal diet and water), NL (normal diet and tomato juice), HA (high fat diet and water) and HL (high fat diet and tomato juice). After 7 weeks, rats were euthanized, and plasma, urine, feces and liver were sampled to analyze the biomarkers related to lipid metabolism, inflammation and oxidative stress. RESULTS: The H diet induced steatosis (grade II) in the HA and HL groups, which was confirmed by the levels of alanine aminotransferase and aspartate aminotransferase, histological examination and the presence of dyslipidemia. The intake of tomato juice led to an accumulation of all-E and Z-lycopene and its metabolites in the livers of these animals; levels were higher in HL than in NL, apparently due to higher absorption (63.07 vs. 44.45%). A significant improvement in the plasma level of high-density lipoprotein was observed in the HL group compared with HA animals, as was an alleviation of oxidative stress through reduction of isoprostanes in the urine. In relation to fatty acid gene expression, an overexpression of several genes related to fatty acid transport, lipid hydrolysis and mitochondrial and peroxisomal ß-fatty acid oxidation was observed in the HL group. CONCLUSIONS: The consumption of tomato juice and tomato products reduced hallmarks of steatosis, plasmatic triglycerides and very low-density lipoproteins, and increased lipid metabolism by inducing an overexpression of genes involved in more efficient fatty acid oxidation.

Tracking (Poly)phenol components from raspberries in ileal fluid.

The (poly)phenols in ileal fluid after ingestion of raspberries were analyzed by targeted and nontargeted LC-MS(n) approaches. Targeted approaches identified major anthocyanin and ellagitannin components at varying recoveries and with considerable interindividual variation. Nontargeted LC-MS(n) analysis using an orbitrap mass spectrometer gave exact mass MS data which were sifted using a software program to select peaks that changed significantly after supplementation. This method confirmed the recovery of the targeted components but also identified novel raspberry-specific metabolites. Some components (including ellagitannin and previously unidentified proanthocyanidin derivatives) may have arisen from raspberry seeds that survived intact in ileal samples. Other components include potential breakdown products of anthocyanins, unidentified components, and phenolic metabolites formed either in the gut epithelia or after absorption into the circulatory system and efflux back into the gut lumen. The possible physiological roles of the ileal metabolites in the large bowel are discussed.

A rosemary extract rich in carnosic acid selectively modulates caecum microbiota and inhibits ß-glucosidase activity, altering fiber and short chain fatty acids fecal excretion in lean and obese female rats.

BACKGROUND: Carnosic acid (CA) and rosemary extracts (RE) show body-weight, energy metabolism and inflammation regulatory properties in animal models but the mechanisms are not yet understood. Gut microbiota plays an important role in the host metabolism and inflammatory status and is modulated by the diet. The aim of this research was to investigate whether a RE enriched in CA affected caecum microbiota composition and activity in a rat model of genetic obesity. METHODS AND PRINCIPAL FINDINGS: A RE (40% CA) was administered with the diet (0.5% w/w) to lean (fa/+) and obese (fa/fa) female Zucker rats for 64 days. Changes in the microbiota composition and ß-glucosidase activity in the caecum and in the levels of macronutrients and short chain fatty acids (SCFA) in feces were examined. The RE increased the Blautia coccoides and Bacteroides/Prevotella groups and reduced the Lactobacillus/Leuconostoc/Pediococccus group in both types of animals. Clostridium leptum was significantly decreased and Bifidobacterium increased only in the lean rats. ß-Glucosidase activity was significantly reduced and fecal fiber excretion increased in the two genotypes. The RE also increased the main SCFA excreted in the feces of the obese rats but decreased them in the lean rats reflecting important differences in the uptake and metabolism of these molecules between the two genotypes. CONCLUSIONS: Our results indicate that the consumption of a RE enriched in CA modifies microbiota composition and decreases ß-glucosidase activity in the caecum of female Zucker rats while it increases fiber fecal elimination. These results may contribute to explain the body weight gain reducing effects of the RE. The mutated leptin receptor of the obese animals significantly affects the microbiota composition, the SCFA fecal excretion and the host response to the RE intake.

Nutritional composition and antioxidant capacity in edible flowers: characterisation of phenolic compounds by HPLC-DAD-ESI/MSn.

Edible flowers are commonly used in human nutrition and their consumption has increased in recent years. The aim of this study was to ascertain the nutritional composition and the content and profile of phenolic compounds of three edible flowers, monks cress (Tropaeolum majus), marigold (Tagetes erecta) and paracress (Spilanthes oleracea), and to determine the relationship between the presence of phenolic compounds and the antioxidant capacity. Proximate composition, total dietary fibre (TDF) and minerals were analysed according to official methods: total phenolic compounds (TPC) were determined with Folin-Ciocalteu's reagent, whereas antioxidant capacity was evaluated using Trolox Equivalent Antioxidant Capacity (TEAC) and Oxygen Radical Absorbance Capacity (ORAC) assays. In addition, phenolic compounds were characterised by HPLC-DAD-MSn. In relation to the nutritional value, the edible flowers had a composition similar to that of other plant foods, with a high water and TDF content, low protein content and very low proportion of total fat-showing significant differences among samples. The levels of TPC compounds and the antioxidant capacity were significantly higher in T. erecta, followed by S. oleracea and T. majus. Thirty-nine different phenolic compounds were tentatively identified, with flavonols being the major compounds detected in all samples, followed by anthocyanins and hydroxycynnamic acid derivatives. In T. erecta small proportions of gallotannin and ellagic acid were also identified.

Persistence of anticancer activity in berry extracts after simulated gastrointestinal digestion and colonic fermentation.

Fruit and vegetable consumption is associated at the population level with a protective effect against colorectal cancer. Phenolic compounds, especially abundant in berries, are of interest due to their putative anticancer activity. After consumption, however, phenolic compounds are subject to digestive conditions within the gastrointestinal tract that alter their structures and potentially their function. However, the majority of phenolic compounds are not efficiently absorbed in the small intestine and a substantial portion pass into the colon. We characterized berry extracts (raspberries, strawberries, blackcurrants) produced by in vitro-simulated upper intestinal tract digestion and subsequent fecal fermentation. These extracts and selected individual colonic metabolites were then evaluated for their putative anticancer activities using in vitro models of colorectal cancer, representing the key stages of initiation, promotion and invasion. Over a physiologically-relevant dose range (0-50 µg/ml gallic acid equivalents), the digested and fermented extracts demonstrated significant anti-genotoxic, anti-mutagenic and anti-invasive activity on colonocytes. This work indicates that phenolic compounds from berries undergo considerable structural modifications during their passage through the gastrointestinal tract but their breakdown products and metabolites retain biological activity and can modulate cellular processes associated with colon cancer.

Bioavailability of anthocyanins and ellagitannins following consumption of raspberries by healthy humans and subjects with an ileostomy.

The fate of anthocyanins, ellagic acid, and ellagitannins was studied following the consumption of 300 g of raspberries by healthy human volunteers and subjects with an ileostomy. Postingestion plasma and urine from the former and ileal fluid and urine from the latter group were collected and analyzed by HPLC-PDA-MS(2). Plasma from the healthy volunteers did not contain detectable quantities of either the native raspberry polyphenolics or their metabolites. The three main raspberry anthocyanins were excreted in urine in both healthy and ileostomy volunteers 0-7 h after ingestion, in quantities corresponding to <0.1% of intake. This indicates a low level of absorption in the small intestine. With ileostomy volunteers 40% of anthocyanins and 23% of the ellagitannin sanguiin H-6 were recovered in ileal fluid with the main excretion period being the first 4 h after raspberry consumption. The recovery of ellagic acid in ileal fluid was 241%, indicating hydrolysis of ellagitannins in the stomach and/or the small intestine. Urinary excretion of ellagic acid and an ellagic acid-O-glucuronide was <1% of intake. No intact or conjugated forms of ellagitannins were detected in urine from either healthy subjects or ileostomy volunteers. However, in healthy subjects, but not the ileostomists, ellagitannins were catabolized with the appearance of urolithin A-O-glucuronide, two of its isomers, and urolithin B-O-glucuronide in urine collected 7-48 h after raspberry consumption. There was marked variation in the urolithin profile of individual volunteers, indicating differences in the colonic microflora responsible for ellagitannin degradation.

Production of bioavailable flavonoid glucosides in fruit juices and green tea by use of fungal alpha-L-rhamnosidases.

Flavonoid glucosides have been reported to be more bioavailable than their rutinoside counterparts. The aim of this study is to describe a first step in the use of alpha-L-rhamnosidases (RhaA and RhaB) from Aspergillus aculeatus as a way to produce functional beverages based on their potentially increased flavonoid bioavailability. Blackcurrant juice (BCJ), orange juice (OJ), and green tea infusion (GT) were incubated with either RhaA or RhaB at 30 degrees C for 10 h. Aliquots of controls and enzyme-treated samples were taken at different time points and analyzed by high-performance liquid chromatography-photodiode-array detector-mass spectrometry of daughter fragments (HPLC-DAD-MS-MS). Both RhaA and RhaB selectively catalyze in situ the removal of terminal rhamnosyl groups in the three beverages despite the heterogeneity of assay conditions such as different rutinosides and pH. Incubation of the three beverages with the two rhamnosidases resulted in a hyperbolic decrease in the flavonoid rutinosides (anthocyanins in BCJ, flavanones in OJ, and flavonols in GT) and a concomitant increase in their flavonoid glucoside counterparts. The time required for conversion of 50% of the rutinoside into the corresponding flavonoid glucoside ranged from 30 min (RhaB-rutin in GT) to 6 h (RhaB-delphinidin 3-rutinoside in BCJ). The results presented in this paper are a step forward in the use of enzyme-treated beverages as a source of bioavailable flavonoid glucosides.