Pasta Structure Affects Mastication, Bolus Properties, and Postprandial Glucose and Insulin Metabolism in Healthy Adults.

BACKGROUND: Structure and protein-starch interactions in pasta products can be responsible for lower postprandial glycemic responses compared with other cereal foods. OBJECTIVES: We tested the effect on postprandial glucose metabolism induced by 2 pasta products, couscous, and bread, through their structural changes during mastication and simulated gastric digestion. METHODS: Two randomized controlled trials (n = 30/trial) in healthy, normal-weight adults (mean BMI of 23.9 kg/m2 (study 1) and 23.0 kg/m2 (study 2)) evaluated postprandial glucose metabolism modulation to portions of durum wheat semolina spaghetti, penne, couscous, and bread each containing 50 g available carbohydrate. A mastication trial involving 26 normal-weight adults was conducted to investigate mastication processes and changes in particle size distribution and microstructure (light microscopy) of boluses after mastication and in vitro gastric digestion. RESULTS: Both pasta products resulted in lower areas under the 2-h curve for blood glucose (-40% for spaghetti and -22% for penne compared with couscous; -41% for spaghetti and -30% for penne compared with bread), compared with the other grain products (P < 0.05). Pasta products required more chews (spaghetti: 34 ± 18; penne: 38 ± 20; bread: 27 ± 13; couscous: 24 ± 17) and longer oral processing (spaghetti: 21 ± 13 s; penne: 23 ± 14 s; bread: 18 ± 9 s; couscous: 14 ± 10 s) compared with bread or couscous (P < 0.01). Pastas contained more large particles (46-67% of total particle area) compared with bread (0-30%) and couscous (1%) after mastication and in vitro gastric digestion. After in vitro gastric digestion, pasta samples still contained large areas of nonhydrolyzed starch embedded within the protein network; the protein in bread and couscous was almost entirely digested, and the starch was hydrolyzed. CONCLUSIONS: Preservation of the pasta structure during mastication and gastric digestion explains slower starch hydrolysis and, consequently, lower postprandial glycemia compared with bread or couscous prepared from the same durum wheat semolina flour in healthy adults. The postprandial in vivo trials were registered at clinicaltrials.gov as NCT03098017 and NCT03104686.

Pasta Structure Affects Mastication, Bolus Properties, and Postprandial Glucose and Insulin Metabolism in Healthy Adults.

BACKGROUND: Structure and protein-starch interactions in pasta products can be responsible for lower postprandial glycemic responses compared with other cereal foods. OBJECTIVES: We tested the effect on postprandial glucose metabolism induced by 2 pasta products, couscous, and bread, through their structural changes during mastication and simulated gastric digestion. METHODS: Two randomized controlled trials (n = 30/trial) in healthy, normal-weight adults (mean BMI of 23.9 kg/m2 (study 1) and 23.0 kg/m2 (study 2)) evaluated postprandial glucose metabolism modulation to portions of durum wheat semolina spaghetti, penne, couscous, and bread each containing 50 g available carbohydrate. A mastication trial involving 26 normal-weight adults was conducted to investigate mastication processes and changes in particle size distribution and microstructure (light microscopy) of boluses after mastication and in vitro gastric digestion. RESULTS: Both pasta products resulted in lower areas under the 2-h curve for blood glucose (-40% for spaghetti and -22% for penne compared with couscous; -41% for spaghetti and -30% for penne compared with bread), compared with the other grain products (P < 0.05). Pasta products required more chews (spaghetti: 34 ± 18; penne: 38 ± 20; bread: 27 ± 13; couscous: 24 ± 17) and longer oral processing (spaghetti: 21 ± 13 s; penne: 23 ± 14 s; bread: 18 ± 9 s; couscous: 14 ± 10 s) compared with bread or couscous (P < 0.01). Pastas contained more large particles (46-67% of total particle area) compared with bread (0-30%) and couscous (1%) after mastication and in vitro gastric digestion. After in vitro gastric digestion, pasta samples still contained large areas of nonhydrolyzed starch embedded within the protein network; the protein in bread and couscous was almost entirely digested, and the starch was hydrolyzed. CONCLUSIONS: Preservation of the pasta structure during mastication and gastric digestion explains slower starch hydrolysis and, consequently, lower postprandial glycemia compared with bread or couscous prepared from the same durum wheat semolina flour in healthy adults.The postprandial in vivo trials were registered at clinicaltrials.gov as NCT03098017 and NCT03104686.

Metabotypes of flavan-3-ol colonic metabolites after cranberry intake: elucidation and statistical approaches.

PURPOSE: Extensive inter-individual variability exists in the production of flavan-3-ol metabolites. Preliminary metabolic phenotypes (metabotypes) have been defined, but there is no consensus on the existence of metabotypes associated with the catabolism of catechins and proanthocyanidins. This study aims at elucidating the presence of different metabotypes in the urinary excretion of main flavan-3-ol colonic metabolites after consumption of cranberry products and at assessing the impact of the statistical technique used for metabotyping. METHODS: Data on urinary concentrations of phenyl-γ-valerolactones and 3-(hydroxyphenyl)propanoic acid derivatives from two human interventions has been used. Different multivariate statistics, principal component analysis (PCA), cluster analysis, and partial least square-discriminant analysis (PLS-DA), have been considered. RESULTS: Data pre-treatment plays a major role on resulting PCA models. Cluster analysis based on k-means and a final consensus algorithm lead to quantitative-based models, while the expectation-maximization algorithm and clustering according to principal component scores yield metabotypes characterized by quali-quantitative differences in the excretion of colonic metabolites. PLS-DA, together with univariate analyses, has served to validate the urinary metabotypes in the production of flavan-3-ol metabolites and to confirm the robustness of the methodological approach. CONCLUSIONS: This work proposes a methodological workflow for metabotype definition and highlights the importance of data pre-treatment and clustering methods on the final outcomes for a given dataset. It represents an additional step toward the understanding of the inter-individual variability in flavan-3-ol metabolism. TRIAL REGISTRATION: The acute study was registered at clinicaltrials.gov as NCT02517775, August 7, 2015; the chronic study was registered at clinicaltrials.gov as NCT02764749, May 6, 2016.

A wheat aleurone-rich diet improves oxidative stress but does not influence glucose metabolism in overweight/obese individuals: Results from a randomized controlled trial.

BACKGROUND AND AIMS: Aleurone is the innermost layer of wheat bran, rich in fiber, minerals, vitamins, phenolic compounds, and betaine. The metabolic effects of aleurone rich foods are still unknown. Our aim was to investigate the effects of consuming a Wheat Aleurone rich diet vs. a Refined Wheat diet for 8 weeks on fasting and postprandial glycemic and lipid metabolism, inflammation, and oxidative stress in overweight/obese individuals. METHODS AND RESULTS: According to a randomized cross-over study design, 23 overweight/obese individuals, age 56 ± 9 years (M±SD), were assigned to two isoenergetic diet - Wheat Aleurone and Refined Wheat diets - for 8 weeks. The diets were similar for macronutrient composition but different for the aleurone content (40-50 g/day in the Wheat Aleurone diet). After each diet, fasting and postprandial plasma metabolic profile, ferulic acid metabolites and 8-isoprostane concentrations in 24-h urine samples were evaluated. Compared with the Refined Wheat Diet, the Wheat Aleurone Diet increased fasting plasma concentrations of betaine by 15% (p = 0.042) and decreased the excretion of 8-isoprostane by 33% (p = 0.035). Conversely, it did not affect the fasting and postprandial glucose, insulin and triglyceride responses, homocysteine, and C-Reactive Protein concentrations, nor excretion of phenolic metabolites. CONCLUSION: An 8-week Wheat Aleurone Diet improves the oxidative stress and increases plasma betaine levels in overweight/obese individuals with an increased cardiometabolic risk. However, further studies with longer duration and larger sample size are needed to evaluate the benefits of aleurone-rich foods on glucose and lipid metabolism in individuals with more severe metabolic abnormalities. CLINICAL TRIAL REGISTRY NUMBER: NCT02150356, (https://clinicaltrials.gov).

Effect of coffee and cocoa-based confectionery containing coffee on markers of cardiometabolic health: results from the pocket-4-life project.

PURPOSE: Coffee is an important source of bioactive compounds, including caffeine, trigonelline, and phenolic compounds. Several studies have highlighted the preventive effects of coffee consumption on major cardiometabolic (CM) diseases, but the impact of different coffee dosages on markers of CM risk in a real-life setting has not been fully understood. This study aimed to investigate the effect of coffee and cocoa-based confectionery containing coffee consumption on several CM risk factors in healthy subjects. METHODS: In a three-arm, crossover, randomized trial, 21 volunteers were assigned to consume in a random order for 1 month: 1 cup of espresso coffee/day, 3 cups of espresso coffee/day, and 1 cup of espresso coffee plus 2 cocoa-based products containing coffee, twice per day. At the last day of each treatment, blood samples were collected and used for the analysis of inflammatory markers, trimethylamine N-oxide, nitric oxide, blood lipids, and markers of glucose/insulin metabolism. Moreover, anthropometric parameters and blood pressure were measured. Finally, food consumption during the interventions was monitored. RESULTS: After 1 month, energy intake did not change among treatments, while significant differences were observed in the intake of saturated fatty acids, sugars, and total carbohydrates. No significant effect on CM markers was observed following neither the consumption of different coffee dosages nor after cocoa-based products containing coffee. CONCLUSIONS: The daily consumption of common dosages of coffee and its substitution with cocoa-based products containing coffee showed no effect on CM risk factors in healthy subjects. TRIAL REGISTRATION NUMBER: Registered at clinicaltrials.gov as NCT03166540, May 21, 2017.

The importance of glycemic index on post-prandial glycaemia in the context of mixed meals: A randomized controlled trial on pasta and rice.

BACKGROUND AND AIMS: Post-prandial glycemic response (PPGR) depends on the intrinsic characteristic of the carbohydrate-rich foods as well as on the amount and type of other nutrients. This study aimed to explore whether the addition of condiments can affect the difference in PPGR between a low and a medium-high Glycemic Index (GI) food. METHODS AND RESULTS: Spaghetti (S) and rice ® were consumed plain and after adding tomato sauce and extra virgin olive oil (TEVOO), or pesto sauce (P). The GI of R (63 ± 3) was statistically higher than that of S (44 ± 7) (p = 0.003). The Incremental Area Under the Curve (IAUC) for R was significantly greater than S (124.2 ± 12.1 and 82.1 ± 12.9 mmol∗min/L respectively) (p = 0.016) for blood glucose but not for insulin (1192.6 ± 183.6 and 905.2 ± 208.9 mU∗min/L, respectively) (p = 0.076). There were no significant differences after the addition of either TEVOO or P. The postprandial peaks of blood glucose and insulin for R (6.7 ± 0.3 mmol/L and 36.4 ± 4.9 mU/L, respectively) were significantly higher compared to S (6.0 ± 0.2 mmol/L and 26.7 ± 3.6 mU/L, respectively) (p = 0.033 and p = 0.025). The postprandial peak for insulin remained significantly higher with P (36.8 ± 3.7 and 28.6 ± 2.9 mU/L for R + P and S + P, p = 0.045) but not with EVOO (p = 0.963). Postprandial peaks for blood glucose were not significantly different with condiment. CONCLUSIONS: The differences in PPGR were significant between spaghetti and rice consumed plain, they reduced or disappeared with fat adding, depending on the type of condiment used. REGISTRATION NUMBER: (www.clinicaltrial.gov):NCT03104712.

Body weight of individuals with obesity decreases after a 6-month high pasta or low pasta Mediterranean diet weight-loss intervention.

BACKGROUND & AIMS: The effect of pasta consumption within a low-energy Mediterranean diet on body weight regulation has been scarcely explored. This paper investigates the effect of two Mediterranean diets, which differed for lower or higher pasta intake, on body weight change in individuals with obesity. METHODS & RESULTS: Forty-nine volunteers finished a quasi-experimental 6-month two-parallel group dietary intervention. Participants were assigned to a low-energy high pasta (HP) or to a low-energy low Pasta (LP) group on the basis of their pasta intake (HP ≥ 5 or LP ≤ 3 times/week). Anthropometrics, blood pressure and heart rate were measured every month. Weight maintenance was checked at month 12. Body composition (bioelectrical impedance analysis, BIA), food intake (24-h recall plus a 7-day carbohydrate record) and the perceived quality of life (36-item short-form health survey, SF-36) were assessed at baseline, 3 and 6 months. Blood samples were collected at baseline and month 6 to assess glucose and lipid metabolism. After 6-month intervention, body weight reduction was -10 ± 8% and -7 ± 4% in HP and LP diet, respectively, and it remained similar at month 12. Both dietary interventions improved anthropometric parameters, body composition, glucose and lipid metabolism, but no significant differences were observed between treatment groups. No differences were observed for blood pressure and heart rate between treatments and among times. HP diet significantly improved perception of quality of life for the physical component. CONCLUSIONS: Independent of pasta consumption frequency, low-energy Mediterranean diets were successful in improving anthropometrics, physiological parameters and dietary habits after a 6-month weight-loss intervention. This trial was registered at clinicaltrials.gov as NCT03341650.

Critical and emerging topics in dietary carbohydrates and health.

Multiple factors may affect the metabolic fate of carbohydrates. Today, well-standardised and accepted methods may allow for the definitions of the changes in the glucose and insulin curves following the ingestion of either carbohydrate-based and other foods. More debate is still raised on the clinical meaning of these classifications when used at a population level, while emphasis is raised on the approach to carbohydrate metabolism on an individual basis. Within these ranges of applications, other compounds, such as plant polyphenols, may favourably add synergic effects through the modulation of carbohydrate digestion and glucose metabolic steps, resulting in lowering postprandial glucose and insulin levels. Finally, a growing knowledge suggests that the balance of dietary fructose and individual physical activity represent the key point to address the compound towards either positive, energy sparing effects, or a degenerative metabolic burden. The carbohydrate quality within a whole dietary and lifestyle pattern may therefore challenge the individual balance towards health or disease.

Phenyl-γ-valerolactones and phenylvaleric acids, the main colonic metabolites of flavan-3-ols: synthesis, analysis, bioavailability, and bioactivity.

Covering: 1958 to June 2018 Phenyl-γ-valerolactones (PVLs) and their related phenylvaleric acids (PVAs) are the main metabolites of flavan-3-ols, the major class of flavonoids in the human diet. Despite their presumed importance, these gut microbiota-derived compounds have, to date, in terms of biological activity, been considered subordinate to their parent dietary compounds, the flavan-3-ol monomers and proanthocyanidins. In this review, the role and prospects of PVLs and PVAs as key metabolites in the understanding of the health features of flavan-3-ols have been critically assessed. Among the topics covered, are proposals for a standardised nomenclature for PVLs and PVAs. The formation, bioavailability and pharmacokinetics of PVLs and PVAs from different types of flavan-3-ols are discussed, taking into account in vitro and animal studies, as well as inter-individual differences and the existence of putative flavan-3-ol metabotypes. Synthetic strategies used for the preparation of PVLs are considered and the methodologies for their identification and quantification assessed. Metabolomic approaches unravelling the role of PVLs and PVAs as biomarkers of intake are also described. Finally, the biological activity of these microbial catabolites in different experimental models is summarised. Knowledge gaps and future research are considered in this key area of dietary (poly)phenol research.

Glucose- and Lipid-Related Biomarkers Are Affected in Healthy Obese or Hyperglycemic Adults Consuming a Whole-Grain Pasta Enriched in Prebiotics and Probiotics: A 12-Week Randomized Controlled Trial.

BACKGROUND: Synbiotic foods, which combine the action of prebiotics and probiotics along the gastrointestinal tract, can affect inflammatory and glucose-related markers. OBJECTIVE: The aim of this study was to investigate the effects on inflammatory and glycemia-related markers of a whole-grain pasta containing barley ß-glucans and Bacillus coagulans BC30, 6086 in healthy overweight or obese volunteers. METHODS: A single-blind, parallel, randomized, placebo-controlled dietary intervention study was carried out. Forty-one healthy sedentary overweight (body mass index [BMI] 25-29.9 kg/m2) and obese (BMI ≥30) volunteers, aged 30-65 y and low consumers of fruit and vegetables, ate 1 serving/d of whole-grain control (CTR) or innovative (INN) pasta for 12 wk and maintained their habitual diets. Biological samples were collected at baseline and every 4 wk for primary (plasma high-sensitivity C-reactive protein [hs-CRP] and fasting plasma lipid profile) and secondary outcomes (glycemia-related markers, blood pressure, fecal microbiota composition, and body weight). Between (CTR compared with INN) and within (among weeks) group differences were tested for the whole population and for subgroups stratified by baseline values of BMI (≥30) and glycemia (≥100 mg/dL). RESULTS: INN or CTR pasta consumption had no effect on primary and secondary outcomes over time, except for a significant increase in plasma γ-glutamyltransferase (GGT) after 12 wk of CTR pasta consumption. Comparisons between intervention groups revealed differences only at 12 wk: plasma GGT was higher in the CTR group; plasma hs-CRP, plasma LDL/HDL cholesterol ratio, and Bifidobacterium spp. were lower in the INN subgroup of obese volunteers; plasma resistin was lower and Faecalibacterium prausnitzii abundance was higher in the INN subgroup of hyperglycemic volunteers. CONCLUSIONS: A daily serving of a synbiotic whole-grain pasta had limited effects on primary and secondary outcomes in the entire group of volunteers but affected glycemia- and lipid-related markers and resistin in a subgroup of healthy obese or hyperglycemic volunteers. This trial was registered at clinicaltrials.gov as NCT02236533.

Dietary intake of (poly)phenols in children and adults: cross-sectional analysis of UK National Diet and Nutrition Survey Rolling Programme (2008-2014).

PURPOSE: Current evidence accounts for the role of (poly)phenolic compounds in the prevention of non-communicable diseases. Detailed information on population-level intakes is required to translate these findings into recommendations. This work aimed to estimate (poly)phenol intake in the UK population using data from a nationally representative survey. METHODS: Data from 9374 participants (4636 children aged 1.5-18 years and 4738 adults aged 19 years and over) from the National Diet and Nutrition Survey Rolling Programme (NDNS RP) 2008-2014 was used. (Poly)phenol content of foods consumed in the NDNS RP was identified using Phenol-Explorer and through literature searches. Data on flavonoids, phenolic acids, and stilbenes were collected. Total (poly)phenol content was also assessed. RESULTS: Mean total (poly)phenol intake ranged from 266.6 ± 166.1 mg/day in children aged 1.5-3 years to 1035.1 ± 544.3 mg/day in adults aged 65 years and over, with flavan-3-ols and hydroxycinnamic acids being the most consumed (poly)phenols across all age groups. (Poly)phenol intake was higher in males in all age groups except for adults aged 19-34 and 50-64 years, where intakes were marginally higher in females. Energy-adjusted intakes accounted for the pattern of increasing (poly)phenol intakes with age and a higher intake was observed in females across all age groups, with the exception of children aged 1.5-3 years. The main food sources were non-alcoholic beverages and fruits, being the main compounds flavan-3-ols and caffeoylquinic acids. CONCLUSIONS: This analysis provides estimates of (poly)phenol intake from a representative sample of the UK general population, which can help inform the health implications of (poly)phenol intake.

Inter-individual variability in the production of flavan-3-ol colonic metabolites: preliminary elucidation of urinary metabotypes.

PURPOSE: There is much information on the bioavailability of (poly)phenolic compounds following acute intake of various foods. However, there are only limited data on the effects of repeated and combined exposure to specific (poly)phenol food sources and the inter-individual variability in their bioavailability. This study evaluated the combined urinary excretion of (poly)phenols from green tea and coffee following daily consumption by healthy subjects in free-living conditions. The inter-individual variability in the production of phenolic metabolites was also investigated. METHODS: Eleven participants consumed both tablets of green tea and green coffee bean extracts daily for 8 weeks and 24-h urine was collected on five different occasions. The urinary profile of phenolic metabolites and a set of multivariate statistical tests were used to investigate the putative existence of characteristic metabotypes in the production of flavan-3-ol microbial metabolites. RESULTS: (Poly)phenolic compounds in the green tea and green coffee bean extracts were absorbed and excreted after simultaneous consumption, with green tea resulting in more inter-individual variability in urinary excretion of phenolic metabolites. Three metabotypes in the production of flavan-3-ol microbial metabolites were tentatively defined, characterized by the excretion of different amounts of trihydroxyphenyl-γ-valerolactones, dihydroxyphenyl-γ-valerolactones, and hydroxyphenylpropionic acids. CONCLUSIONS: The selective production of microbiota-derived metabolites from flavan-3-ols and the putative existence of characteristic metabotypes in their production represent an important development in the study of the bioavailability of plant bioactives. These observations will contribute to better understand the health effects and individual differences associated with consumption of flavan-3-ols, arguably the main class of flavonoids in the human diet.

Bioavailability and pharmacokinetic profile of grape pomace phenolic compounds in humans.

Grape pomace, the major byproduct of the wine and juice industry, is a relevant source of bioactive phenolic compounds. However, polyphenol bioavailability in humans is not well understood, and the inter-individual variability in the production of phenolic metabolites has not been comprehensively assessed to date. The pharmacokinetic and excretive profiles of phenolic metabolites after the acute administration of a drink made from red grape pomace was here investigated in ten volunteers. A total of 35 and 28 phenolic metabolites were quantified in urine and plasma, respectively. The main circulating metabolites included phenyl-γ-valerolactones, hydroxybenzoic acids, simple phenols, hydroxyphenylpropionic acids, hydroxycinnamates, and (epi)catechin phase II conjugates. A high inter-individual variability was shown both in urine and plasma samples, and different patterns of circulating metabolites were unravelled by applying unsupervised multivariate analysis. Besides the huge variability in the production of microbial metabolites of colonic origin, an important variability was observed due to phase II conjugates. These results are of interest to further understand the potential health benefits of phenolic metabolites on individual basis.

Nature and Cognitive Perception of 4 Different Breakfast Meals Influence Satiety-Related Sensations and Postprandial Metabolic Responses but Have Little Effect on Food Choices and Intake Later in the Day in a Randomized Crossover Trial in Healthy Men.

Background: Regular breakfast consumption is associated with better health status and healthier food intake throughout the day, but this association is a complex interaction of several factors. Objective: This study aimed to investigate the effect of nutritional and cognitive-perceived characteristics of breakfast on metabolic and behavioral variables related to food intake. Methods: The study was a randomized, crossover, controlled trial, with 4 experimental conditions consisting of 3 iso-energetic breakfasts and 1 energy-free control meal. Breakfasts had similar nutritional profiles but differed for glycemic index (GI), glycemic load (GL), and perceived healthiness, satiety, palatability, or energy content. Fifteen healthy normal-weight men [means ± SDs; age: 24 ± 2 y; body mass index (BMI; kg/m2) 23.4 ± 1.6] underwent each experimental condition in random order during 4 different weeks, separated by ≥1-wk washout. On the third day of each intervention week, postprandial blood variables (with insulin as primary outcome), satiety ratings, and food intake during an ad libitum lunch consumed 4 h after breakfast (secondary outcomes) were measured for each experimental condition. Results: A main effect of time, treatment, and time × treatment was found for postprandial insulin, glucose, and nonesterified fatty acids (P < 0.001 for all) after having the 3 iso-energetic breakfasts or the energy-free control one. Postprandial satiety was similar for the 3 energy-containing breakfasts, but higher when compared with the energy-free control (P < 0.001). No difference in energy intake was observed for the ad libitum lunch, whereas prolonged breakfast skipping was compensated by an increase (around +10%) in the average energy intake during the rest of the day, resulting in no differences in the total daily energy intake among the 4 conditions. Conclusions: Although other advantages might exist for breakfasts based on low-GI/low-GL foods, our findings support the hypothesis that minor differences in nutritional and perceived characteristics of breakfast are of limited importance regarding medium-term energy intake in healthy men. This trial was registered at clinicaltrials.gov as BRNN-014 NCT02516956.

A nutritional evaluation of various typical Italian breakfast products: a comparison of macronutrient composition and glycaemic index values.

Breakfast foods with lower glycaemic responses are associated with better body weight control. Glycaemic index (GI) values of some commonly consumed breakfast foods in Italy were determined and compared, along with macronutrients. Cakes/pastries were low-medium GI (44-60), with high-sugar and saturated fat and low-fibre. Generally, mueslis and breads were medium GI (62-66 and 59-76, respectively) with higher fibre and lower saturated fat and sugar. The addition of spreads to bread lowered GI (47-66) but increased sugar and saturated fat.

Food perception at lunchtime does not depend on the nutritional and perceived characteristics of breakfast.

Breakfast consumption can entail nutritional advantages positively affecting food choices. This study investigated the effect of minor changes in breakfast composition on the perceived attributes of foods, both at breakfast and at lunchtime. Four breakfasts were defined considering nutritional and perceptual factors. Three breakfasts varied just for a single cereal-based chocolate-containing food item, while a control breakfast mimicked fasting conditions. Breakfast perception was assessed before and after consumption. Subjects rated breakfast energy content on the basis of single items, while judged breakfast healthiness as a whole, suggesting that the combination of different ingredients can modify the perceived health value of foods. Additionally, 4 h after breakfast, a perceptual evaluation of lunch-related food images was performed, without differences among breakfasts. This study extends current knowledge on the relationship between subjective perceptual attributes and objective energy value and food composition, as well as on breakfast impact on food perception at lunchtime.

Trimethylamine-N-Oxide (TMAO)-Induced Impairment of Cardiomyocyte Function and the Protective Role of Urolithin B-Glucuronide.

One of the most recently proposed candidates as a potential trigger for cardiovascular diseases is trimethylamine-N-oxide (TMAO). Possible direct effects of TMAO on myocardial tissue, independent of vascular damage, have been only partially explored so far. In the present study, we assessed the detrimental direct effects of TMAO on cardiomyocyte contractility and intracellular calcium dynamics, and the ability of urolithin B-glucuronide (Uro B-gluc) in counteracting TMAO-induced cell damage. Cell mechanics and calcium transients were measured, and ultrastructural analysis was performed in ventricular cardiomyocytes isolated from the heart of normal adult rats. Cells were either untreated, exposed to TMAO, or to TMAO and Uro B-gluc. TMAO exposure worsened cardiomyocyte mechanics and intracellular calcium handling, as documented by the decrease in the fraction of shortening (FS) and the maximal rate of shortening and re-lengthening, associated with reduced efficiency in the intracellular calcium removal. Ultrastructurally, TMAO-treated cardiomyocytes also exhibited glycogen accumulation, a higher number of mitochondria and lipofuscin-like pigment deposition, suggesting an altered cellular energetic metabolism and a higher rate of protein oxidative damage, respectively. Uro B-gluc led to a complete recovery of cellular contractility and calcium dynamics, and morphologically to a reduced glycogen accumulation. We demonstrated for the first time a direct negative role of TMAO on cardiomyocyte functional properties and the ability of Uro B-gluc in counteracting these detrimental effects.

In vivo administration of urolithin A and B prevents the occurrence of cardiac dysfunction in streptozotocin-induced diabetic rats.

BACKGROUND: Emerging evidence suggests that specific (poly)phenols may constitute new preventative strategies to counteract cell oxidative stress and myocardial tissue inflammation, which have a key role in the patho-physiology of diabetic cardiomyopathy. In a rat model of early diabetes, we evaluated whether in vivo administration of urolithin A (UA) or urolithin B (UB), the main gut microbiota phenolic metabolites of ellagitannin-rich foods, can reduce diabetes-induced microenvironmental changes in myocardial tissue, preventing cardiac functional impairment. METHODS: Adult Wistar rats with streptozotocin-induced type-1 diabetes (n = 29) were studied in comparison with 10 control animals. Diabetic rats were either untreated (n  = â€Š9) or subjected to daily i.p. injection of UA (n = 10) or UB (n = 10). After 3 weeks of hyperglycaemia, hemodynamics, cardiomyocyte contractile properties and calcium transients were measured to assess cardiac performance. The myocardial expression of the pro-inflammatory cytokine fractalkine and proteins involved in calcium dynamics (sarcoplasmic reticulum calcium ATPase, phospholamban and phosphorylated phospholamban) were evaluated by immunoblotting. Plasma, urine and tissue distribution of UA, UB and their phase II metabolites were determined. RESULTS: In vivo urolithin treatment reduced by approximately 30% the myocardial expression of the pro-inflammatory cytokine fractalkine, preventing the early inflammatory response of cardiac cells to hyperglycaemia. The improvement in myocardial microenvironment had a functional counterpart, as documented by the increase in the maximal rate of ventricular pressure rise compared to diabetic group (+18% and +31% in UA and UB treated rats, respectively), and the parallel reduction in the isovolumic contraction time (-12%). In line with hemodynamic data, both urolithins induced a recovery of cardiomyocyte contractility and calcium dynamics, leading to a higher re-lengthening rate (+21%, on average), lower re-lengthening times (-56%), and a more efficient cytosolic calcium clearing (-32% in tau values). UB treatment also increased the velocity of shortening (+27%). Urolithin metabolites accumulated in the myocardium, with a higher concentration of UB and UB-sulphate, potentially explaining the slightly higher efficacy of UB administration. CONCLUSIONS: In vivo urolithin administration may be able to prevent the initial inflammatory response of myocardial tissue to hyperglycaemia and the negative impact of the altered diabetic milieu on cardiac performance.

Glycaemic index, glycaemic load and risk of cutaneous melanoma in a population-based, case-control study.

Glycaemic index (GI) and glycaemic load (GL) are indicators of dietary carbohydrate quantity and quality and have been associated with increased risk of certain cancers and type 2 diabetes. Insulin resistance has been associated with increased melanoma risk. However, GI and GL have not been investigated for melanoma. We present the first study to examine the possible association of GI and GL with melanoma risk. We carried out a population-based, case-control study involving 380 incident cases of cutaneous melanoma and 719 age- and sex-matched controls in a northern Italian region. Dietary GI and GL were computed for each subject using data from a self-administered, semi-quantitative food frequency questionnaire. We computed the odds ratio (OR) for melanoma according to quintiles of distribution of GL and GL among controls. A direct association between melanoma risk and GL emerged in females (OR 2·38; 95 % CI 1·25, 4·52 for the highest v. the lowest quintile of GL score, P for trend 0·070) but not in males. The association in females persisted in the multivariable analysis after adjusting for several potential confounders. There was no evidence of an association between GI and melanoma risk. GL might be associated with melanoma risk in females.

Gastrointestinal stability of urolithins: an in vitro approach.

PURPOSE: Urolithins are bioactive ellagitannin-derived metabolites showing a wide phenotypic variation in their production by the gut microbiota. This work represents a first in vitro step toward the development of new strategies focused on the oral supplementation of urolithins with the aim of overcoming their selective production and making their putative health benefits available for the whole population. METHODS: In order to study their gastrointestinal stability, urolithin A, urolithin B, and urolithin B-glucuronide, as well as ellagic acid, were subjected to a simulated gastrointestinal digestion model consisting of oral, gastric, and pancreatic steps followed by a 24-h fecal fermentation. The effect of the entero-hepatic recirculation on urolithin B-glucuronide, a phase II metabolite, was also investigated. RESULTS: Urolithin B was the molecule able to resist to a greater extent the conditions of the gastrointestinal tract, while urolithin A and ellagic acid were drastically unstable during the colonic step. Conjugation with glucuronic acid, ideally occurring in the liver, conferred to urolithin B an increased stability, which may be interesting in the framework of entero-hepatic recirculation. CONCLUSION: This set of experiments lets hypothesize that orally supplemented urolithins may come into contact with the colonic epithelium and become accessible for uptake or exert local anti-inflammatory activity, overcoming the limitations of enterotypes unable to convert ellagitannins into these putatively beneficial metabolites.