European Journal of Nutrition (v.57, #1)
Gut microbiota functions: metabolism of nutrients and other food components by Ian Rowland; Glenn Gibson; Almut Heinken; Karen Scott; Jonathan Swann; Ines Thiele; Kieran Tuohy (1-24).
The diverse microbial community that inhabits the human gut has an extensive metabolic repertoire that is distinct from, but complements the activity of mammalian enzymes in the liver and gut mucosa and includes functions essential for host digestion. As such, the gut microbiota is a key factor in shaping the biochemical profile of the diet and, therefore, its impact on host health and disease. The important role that the gut microbiota appears to play in human metabolism and health has stimulated research into the identification of specific microorganisms involved in different processes, and the elucidation of metabolic pathways, particularly those associated with metabolism of dietary components and some host-generated substances. In the first part of the review, we discuss the main gut microorganisms, particularly bacteria, and microbial pathways associated with the metabolism of dietary carbohydrates (to short chain fatty acids and gases), proteins, plant polyphenols, bile acids, and vitamins. The second part of the review focuses on the methodologies, existing and novel, that can be employed to explore gut microbial pathways of metabolism. These include mathematical models, omics techniques, isolated microbes, and enzyme assays.
Keywords: Gut microbiota; Microbiome; Microbial metabolism; Food components; Methodology
The role of the microbiome for human health: from basic science to clinical applications by M. Hasan Mohajeri; Robert J. M. Brummer; Robert A. Rastall; Rinse K. Weersma; Hermie J. M. Harmsen; Marijke Faas; Manfred Eggersdorfer (1-14).
The 2017 annual symposium organized by the University Medical Center Groningen in The Netherlands focused on the role of the gut microbiome in human health and disease. Experts from academia and industry examined interactions of prebiotics, probiotics, or vitamins with the gut microbiome in health and disease, the development of the microbiome in early-life and the role of the microbiome on the gut–brain axis. The gut microbiota changes dramatically during pregnancy and intrinsic factors (such as stress), in addition to extrinsic factors (such as diet, and drugs) influence the composition and activity of the gut microbiome throughout life. Microbial metabolites, e.g. short-chain fatty acids affect gut–brain signaling and the immune response. The gut microbiota has a regulatory role on anxiety, mood, cognition and pain which is exerted via the gut–brain axis. Ingestion of prebiotics or probiotics has been used to treat a range of conditions including constipation, allergic reactions and infections in infancy, and IBS. Fecal microbiota transplantation (FMT) highly effective for treating recurrent Clostridium difficile infections. The gut microbiome affects virtually all aspects of human health, but the degree of scientific evidence, the models and technologies and the understanding of mechanisms of action vary considerably from one benefit area to the other. For a clinical practice to be broadly accepted, the mode of action, the therapeutic window, and potential side effects need to thoroughly be investigated. This calls for further coordinated state-of-the art research to better understand and document the human gut microbiome’s effects on human health.
Keywords: Microbiota; Gut; Prebiotics; Probiotics; Vitamins; Colonic fermentation; Inflammatory bowel disease; Irritable bowel syndrome; Gut-brain axis; Obesity
Systematic review of the effects of the intestinal microbiota on selected nutrients and non-nutrients by Colette Shortt; Oliver Hasselwander; Alexandra Meynier; Arjen Nauta; Estefanía Noriega Fernández; Peter Putz; Ian Rowland; Jonathan Swann; Jessica Türk; Joan Vermeiren; Jean-Michel Antoine (25-49).
There is considerable interest in the effects of the intestinal microbiota (IM) composition, its activities in relation with the metabolism of dietary substrates and the impact these effects may have in the development and prevention of certain non-communicable diseases. It is acknowledged that a complex interdependence exists between the IM and the mammalian host and that the IM possesses a far greater diversity of genes and repertoire of metabolic and enzymatic capabilities than their hosts. However, full knowledge of the metabolic activities and interactions of the IM and the functional redundancy that may exist are lacking. Thus, the current review aims to assess recent literature relating to the role played by the IM in the absorption and metabolism of key nutrients and non-nutrients.A systematic review (PROSPERO registration: CRD42015019087) was carried out focussing on energy and the following candidate dietary substrates: protein, carbohydrate, fat, fibre, resistant starch (RS), and polyphenols to further understand the effect of the IM on the dietary substrates and the resulting by-products and host impacts. Particular attention was paid to the characterisation of the IM which are predominantly implicated in each case, changes in metabolites, and indirect markers and any potential impacts on the host.Studies show that the IM plays a key role in the metabolism of the substrates studied. However, with the exception of studies focusing on fibre and polyphenols, there have been relatively few recent human studies specifically evaluating microbial metabolism. In addition, comparison of the effects of the IM across studies was difficult due to lack of specific analysis/description of the bacteria involved. Considerable animal-derived data exist, but experience suggests that care must be taken when extrapolating these results to humans. Nevertheless, it appears that the IM plays a role in energy homeostasis and that protein microbial breakdown and fermentation produced ammonia, amines, phenols and branch chain fatty acids, and a greater diversity in the microbes present. Few recent studies appear to have evaluated the effect of the IM composition and metabolism per se in relation with digestible dietary carbohydrate or fat in humans. Intakes of RS and prebiotics altered levels of specific taxa that selectively metabolised specific prebiotic/carbohydrate-type substances and levels of bifidobacteria and lactobacilli were observed to increase. In controlled human studies, consistent data exist that show a correlation between the intake of fibre and an increase in bifidobacteria and short-chain fatty acids, in particular butyrate, which leads to lower intestinal pH. Dietary polyphenols rely on modification either by host digestive enzymes or those derived from the IM for absorption to occur. In the polyphenol-related studies, a large amount of inter-individual variation was observed in the microbial metabolism and absorption of certain polyphenols.The systematic review demonstrates that the IM plays a major role in the breakdown and transformation of the dietary substrates examined. However, recent human data are limited with the exception of data from studies examining fibres and polyphenols. Results observed in relation with dietary substrates were not always consistent or coherent across studies and methodological limitations and differences in IM analyses made comparisons difficult. Moreover, non-digestible components likely to reach the colon are often not well defined or characterised in studies making comparisons between studies difficult if not impossible. Going forward, further rigorously controlled randomised human trials with well-defined dietary substrates and utilizing omic-based technologies to characterise and measure the IM and their functional activities will advance the field. Current evidence suggests that more detailed knowledge of the metabolic activities and interactions of the IM hold considerable promise in relation with host health.
Keywords: Intestinal microbiota; Metabolism; Metabolites; Dietary substrates
Dietary choline and betaine; associations with subclinical markers of cardiovascular disease risk and incidence of CVD, coronary heart disease and stroke: the Jackson Heart Study by Heather R. Millard; Solomon K. Musani; Daniel T. Dibaba; Sameera A. Talegawkar; Herman A. Taylor; Katherine L. Tucker; Aurelian Bidulescu (51-60).
Several mechanisms have been described through which dietary intake of choline and its derivative betaine may be associated in both directions with subclinical atherosclerosis. We assessed the association of dietary intake of choline and betaine with cardiovascular risk and markers of subclinical cardiovascular disease. Data from 3924 Jackson Heart Study (JHS) African-American participants with complete food frequency questionnaire at baseline and follow-up measurements of heart disease measures were used. Multivariable linear regression models were employed to assess associations between choline and betaine intake with carotid intima-media thickness, coronary artery calcium, abdominal aortic calcium and left ventricular mass. Cox proportional hazards regression models were used to estimate associations with time to incident coronary heart disease (CHD), ischemic stroke and cardiovascular disease (CVD).During an average nine years of follow-up, 124 incident CHD events, 75 incident stroke events and 153 incident CVD events were documented. In women, greater choline intake was associated with lower left ventricular mass (p = 0.0006 for trend across choline quartiles) and with abdominal aortic calcium score. Among all JHS participants, there was a statistically significant inverse association between dietary choline intake and incident stroke, β = −0.33 (p = 0.04). Betaine intake was associated with greater risk of incident CHD when comparing the third quartile of intake with the lowest quartile of intake (HR 1.89, 95 % CI 1.14, 3.15).Among our African-American participants, higher dietary choline intake was associated with a lower risk of incident ischemic stroke, and thus putative dietary benefits. Higher dietary betaine intake was associated with a nonlinear higher risk of incident CHD.
Keywords: Diet; Choline; Betaine; Subclinical measures of cardiovascular disease; Incident coronary heart disease; The Jackson Heart Study
Dietary patterns in an elderly population and their relation with bone mineral density: the Rotterdam Study by Ester A. L. de Jonge; Fernando Rivadeneira; Nicole S. Erler; Albert Hofman; André G. Uitterlinden; Oscar H. Franco; Jessica C. Kiefte-de Jong (61-73).
Our aim was to identify dietary patterns that are associated with bone mineral density (BMD) against a background of relatively high dairy intake in elderly Dutch subjects.Participants were 55 years of age and older (n = 5144) who were enrolled in The Rotterdam Study, a population-based prospective cohort study. Baseline intake of 28 pre-defined food groups was determined using a validated food frequency questionnaire. Dietary patterns were identified using principal component analysis. BMD was measured using dual-energy X-ray absorptiometry at baseline and at three subsequent visits (between 1993 and 2004). Linear mixed modelling was used to longitudinally analyse associations of adherence to each pattern with repeatedly measured BMD (both in Z scores).After adjustment for confounders, two dietary patterns were associated with high BMD: a “Traditional” pattern, characterized by high intake of potatoes, meat and fat (β = 0.06; 95 % CI 0.03, 0.09) and a “Health conscious” pattern, characterized by high intake of fruits, vegetables, poultry and fish (β = 0.06; 95 % CI 0.04, 0.08). The “Processed” pattern, characterized by high intake of processed meat and alcohol, was associated with low BMD (β = −0.03; 95 % CI −0.06, −0.01). Associations of adherence to the “Health conscious” and “Processed” pattern with BMD were independent of body weight and height, whereas the association between adherence to the “Traditional” pattern with BMD was not.Against a background of high dairy intake and independent of anthropometrics, a “Health conscious” dietary pattern may have benefits for BMD, whereas a “Processed” dietary pattern may pose a risk for low BMD.
Keywords: Dietary patterns; Bone mineral density; Principal component analysis; Overall diet; Body weight
Fruit and vegetable consumption and risk of cholecystectomy: a prospective cohort study of women and men by Caroline Nordenvall; Viktor Oskarsson; Alicja Wolk (75-81).
Epidemiologic data on whether consumption of fruit and vegetables (FVs) decreases the risk of gallstone disease are sparse. Therefore, we examined the association between FV consumption and the 14-year risk of symptomatic gallstone disease (defined as occurrence of cholecystectomy) in a large group of middle-aged and elderly persons.Data from two population-based cohorts were used, which included 74,554 men and women (born 1914–1952). Participants filled in a food frequency questionnaire in the late fall of 1997 and were followed up for cholecystectomy between 1998 and 2011 via linkage to the Swedish Patient Register. Cox regression models were used to obtain hazard ratios (HRs).During 939,715 person-years of follow-up, 2120 participants underwent a cholecystectomy (1120 women and 1000 men). An inverse association between FV consumption and risk of cholecystectomy was observed in age- and sex-adjusted analyses (P trend = .036) but not in confounder-adjusted analyses (P trend = .43). The multivariable-adjusted HR was 0.95 (95 % CI 0.83–1.08) for the highest compared with the lowest sex-specific quartile of FV consumption. There was no evidence of interactions with age (P = .25) or sex (P = .72) in analyses pooled by sex. However, an age-by-FV consumption interaction was observed in separate analyses of women (P = .010), with decreased HRs of cholecystectomy for ages up to 60 years.This study supports an inverse association between FV consumption and risk cholecystectomy in women, although the association was restricted to women aged 48–60 years. In contrast, the study does not support an association in men.
Keywords: Fruit consumption; Vegetable consumption; Gallbladder disease; Cohort study
Dietary Salba (Salvia hispanica L.) ameliorates the adipose tissue dysfunction of dyslipemic insulin-resistant rats through mechanisms involving oxidative stress, inflammatory cytokines and peroxisome proliferator-activated receptor γ by M. R. Ferreira; S. M. Alvarez; P. Illesca; M. S. Giménez; Y. B. Lombardo (83-94).
Rats fed a long-term sucrose-rich diet (SRD) developed adipose tissue dysfunction. In the adipose tissue of these SRD-fed rats, the present study analyzed the possible beneficial effects of dietary Salba (chia) seeds in improving or reversing the depletion of antioxidant defenses, changes in pro-inflammatory cytokines and ROS production.Wistar rats were fed a SRD for 3 months. After that, half of the animals continued with the SRD until month 6, while in the other half, corn oil was replaced by chia seeds for 3 months (SRD + chia). A reference group consumed a control diet all the time.Compared with the SRD-fed rats, the animals fed a SRD + chia showed a reduction in epididymal fat pad weight; the activities of antioxidant enzymes CAT, SOD and GPx returned to control values, while GR significantly improved; mRNA GPx increased, and both mRNA SOD and the redox state of glutathione returned to control values; a significant increase in the expression of Nrf2 was recorded. These results were accompanied by a decrease in XO activity and ROS contents as well as plasma IL-6 and TNF-α levels. Chia seeds reversed the decrease in PPARγ protein mass level and increased the n-3/n-6 fatty acids ratio of membrane phospholipids. Besides, dyslipidemia and insulin sensitivity were normalized.This study provides new information concerning some mechanisms related to the beneficial effects of dietary chia seeds in reversing adipose tissue oxidative stress and improving the adipose tissue dysfunction induced by a SRD.
Keywords: α-linolenic acid (ALA); Adipose tissue; Dyslipidemia; High-sucrose diet; Oxidative stress; Insulin resistance
Effect of probiotics and synbiotics on blood glucose: a systematic review and meta-analysis of controlled trials by Elham Nikbakht; Saman Khalesi; Indu Singh; Lauren Therese Williams; Nicholas P. West; Natalie Colson (95-106).
High fasting blood glucose (FBG) can lead to chronic diseases such as diabetes mellitus, cardiovascular and kidney diseases. Consuming probiotics or synbiotics may improve FBG. A systematic review and meta-analysis of controlled trials was conducted to clarify the effect of probiotic and synbiotic consumption on FBG levels.PubMed, Scopus, Cochrane Library, and Cumulative Index to Nursing and Allied Health Literature databases were searched for relevant studies based on eligibility criteria. Randomized or non-randomized controlled trials which investigated the efficacy of probiotics or synbiotics on the FBG of adults were included. Studies were excluded if they were review articles and study protocols, or if the supplement dosage was not clearly mentioned.A total of fourteen studies (eighteen trials) were included in the analysis. Random-effects meta-analyses were conducted for the mean difference in FBG. Overall reduction in FBG observed from consumption of probiotics and synbiotics was borderline statistically significant (−0.18 mmol/L 95 % CI −0.37, 0.00; p = 0.05). Neither probiotic nor synbiotic subgroup analysis revealed a significant reduction in FBG. The result of subgroup analysis for baseline FBG level ≥7 mmol/L showed a reduction in FBG of 0.68 mmol/L (−1.07, −0.29; ρ < 0.01), while trials with multiple species of probiotics showed a more pronounced reduction of 0.31 mmol/L (−0.58, −0.03; ρ = 0.03) compared to single species trials.This meta-analysis suggests that probiotic and synbiotic supplementation may be beneficial in lowering FBG in adults with high baseline FBG (≥7 mmol/L) and that multispecies probiotics may have more impact on FBG than single species.
Keywords: Probiotics; Synbiotics; Fasting blood glucose; Hyperglycemia
Pre-pregnancy caffeine and caffeinated beverage intake and risk of spontaneous abortion by Audrey J. Gaskins; Janet W. Rich-Edwards; Paige L. Williams; Thomas L. Toth; Stacey A. Missmer; Jorge E. Chavarro (107-117).
To investigate the relation between pre-pregnancy caffeine and caffeinated beverage intake and risk of spontaneous abortion (SAB).Our prospective cohort study included 15,590 pregnancies from 11,072 women with no history of SAB in the Nurses’ Health Study II (1991–2009). Beverage intake was assessed every 4 years using a validated questionnaire. Pregnancies were self-reported with case pregnancies lost spontaneously at <20 weeks gestation. Multivariable log-binomial regression models with generalized estimating equations were used to estimate the relative risks (RRs) and 95 % confidence intervals (CIs).There was a positive linear trend across categories of pre-pregnancy caffeine intake and risk of SAB such that women consuming >400 mg/day had 1.11 (95 % CI 0.98, 1.25) times the risk of SAB compared to women consuming <50 mg/day (p trend = 0.05). Total coffee intake had a positive, linear association with SAB. Compared to women with no pre-pregnancy coffee intake, women consuming ≥4 servings/day had a 20 % (6, 36 %) increased risk of SAB (p trend = 0.01). There was no difference in the association between caffeinated and decaffeinated coffee and risk of SAB. Pre-pregnancy intake of caffeinated tea, caffeinated soda, and decaffeinated soda had no association with SAB.Pre-pregnancy coffee consumption at levels ≥4 servings/day is associated with increased risk of SAB, particularly at weeks 8–19.
Keywords: Caffeine; Coffee; Miscarriage; Pregnancy; Spontaneous abortion
Metabolic adaptations to HFHS overfeeding: how whole body and tissues postprandial metabolic flexibility adapt in Yucatan mini-pigs by Sergio Polakof; Didier Rémond; Annick Bernalier-Donadille; Mathieu Rambeau; Estelle Pujos-Guillot; Blandine Comte; Dominique Dardevet; Isabelle Savary-Auzeloux (119-135).
In the present study, we aimed to metabolically characterize the postprandial adaptations of the major tissues involved in energy, lipids and amino acids metabolisms in mini-pigs.Mini-pigs were fed on high-fat–high-sucrose (HFHS) diet for 2 months and several tissues explored for metabolic analyses. Further, the urine metabolome was followed over the time to picture the metabolic adaptations occurring at the whole body level following overfeeding.After 2 months of HFHS consumption, mini-pigs displayed an obese phenotype characterized by high circulating insulin, triglycerides and cholesterol levels. At the tissue level, a general (muscle, adipose tissue, intestine) reduction in the capacity to phosphorylate glucose was observed. This was also supported by the enhanced hepatic gluconeogenesis potential, despite the concomitant normoglycaemia, suggesting that the high circulating insulin levels would be enough to maintain glucose homoeostasis. The HFHS feeding also resulted in a reduced capacity of two other pathways: the de novo lipogenesis, and the branched-chain amino acids transamination. Finally, the follow-up of the urine metabolome over the time allowed determining breaking points in the metabolic trajectory of the animals.Several features confirmed the pertinence of the animal model, including increased body weight, adiposity and porcine obesity index. At the metabolic level, we observed a perturbed glucose and amino acid metabolism, known to be related to the onset of the obesity. The urine metabolome analyses revealed several metabolic pathways potentially involved in the obesity onset, including TCA (citrate, pantothenic acid), amino acids catabolism (cysteine, threonine, leucine).
Keywords: High-fat–high-sucrose diet; Mini-pigs; Glucose and lipid metabolism; Metabolomics; Postprandial
Patterns of added sugars intake by eating occasion among a nationally representative sample of Australians by Jimmy Chun Yu Louie; Anna M. Rangan (137-154).
To examine the eating occasion (EO) where most added sugars (AS) were consumed using a nationally representative dataset.Plausible dietary data from the Australian Health Survey respondents (n = 8202), collected by a multiple-pass 24-h recall, were analyzed. EO was self-reported during the recall. AS content of the foods reported was estimated using a previously published method. Proportion of daily AS consumed (%ASdaily) and the main food sources, at each EO, were calculated. Differences between children/adolescents and adults were tested by one-way ANOVA. Further stratification by age group and sex was performed.The majority of the %ASdaily came from non-main meal occasions (NMMOs; 48.3 %, 95 % CI 47.5–49.0 %), followed by breakfast/brunch (20.6 %, 95 % CI 20.1–21.1 %). Children and adolescents consumed more %ASdaily during NMMOs compared with adults (52 vs. 47 %; p < 0.001), while girls/women consumed more %ASdaily during NMMO compared with boys (54 vs. 49 %; p = 0.002) and men (50 vs. 45 %; p < 0.001). Sugar-sweetened beverages were the top contributors to AS at lunch, dinner and NMMOs, while sugar and sweet spreads were the top contributor at breakfast/brunch. Other top contributors at NMMOs included “other foods,” ice cream and cakes and biscuits, pastries and batter-based products.Australians consumed nearly half of %ASdaily during NMMOs, most of which came from high-sugar energy-dense nutrient-poor foods. While the common perception that most AS come from snacks holds true, our results suggest that main meals are also important intervention targets.
Keywords: Added sugars; Australians; Eating occasion
Donkey milk consumption exerts anti-inflammatory properties by normalizing antimicrobial peptides levels in Paneth’s cells in a model of ileitis in mice by Sophie Yvon; Maïwenn Olier; Mathilde Leveque; Gwenaëlle Jard; Helene Tormo; Djamila Ali Haimoud-Lekhal; Magali Peter; Hélène Eutamène (155-166).
In this study, we showed the beneficial effects of donkey milk (DM) on inflammatory damages, endogenous antimicrobial peptides levels and fecal microbiota profile in a mice model of Crohn’s disease. Nowadays, new strategies of microbiome manipulations are on the light involving specific diets to induce and/or to maintain clinical remission. Interest of DM is explained by its high levels of antimicrobial peptides which confer it anti-inflammatory properties.C57BL/6 mice were orally administered with or without indomethacin for 5 days and co-treated with vehicle, DM or heated DM during 7 days. Intestinal length and macroscopic damage scores (MDSs) were determined; ileal samples were taken off for microscopic damage (MD), lysozyme immunostaining and mRNA α-defensin assessments. Ileal luminal content and fecal pellets were collected for lysozyme enzymatic activity and lipocalin-2 (LCN-2) evaluations. Fecal microbiota profiles were compared using a real-time quantitative PCR-based analysis.Administration of indomethacin caused an ileitis in mice characterized by (1) a decrease in body weight and intestinal length, (2) a significant increase in MDS, MD and LCN-2, (3) a reduction in both α-defensin mRNA expression and lysozyme levels in Paneth’s cells reflected by a decrease in lysozyme activity in feces, and (4) a global change in relative abundance of targeted microbial communities. DM treatment significantly reduced almost of all these ileitis damages, whereas heated DM has no impact on ileitis.DM consumption exerts anti-inflammatory properties in mice by restoring the endogenous levels of antimicrobial peptides which contribute in turn to reduce microbiota imbalance.
Keywords: Donkey milk; Antimicrobial peptides; Crohn’s disease; Ileitis; Dysbiosis
Effects of low-glycemic-index diets in pregnancy on maternal and newborn outcomes in pregnant women: a meta-analysis of randomized controlled trials by Ru Zhang; Shufen Han; Guo-Chong Chen; Zeng-Ning Li; Irma Silva-Zolezzi; Gerard Vinyes Parés; Yi Wang; Li-Qiang Qin (167-177).
Maternal diet with a high glycemic index (GI) is associated with fetal overgrowth and higher infant body adiposity. Effects of low-GI diet on maternal and newborn outcomes have been assessed in both healthy pregnancy and gestational diabetes mellitus, but the results remain inconclusive. This meta-analysis aimed to examine the effects of low-GI diets on maternal and newborn outcomes.PubMed, Clinical Trials, and Cochrane Library databases were searched for relevant randomized trials up to January 2016. Random- or fixed-effects models were used to calculate combined treatment effects.A total of 11 trials involving 1985 women were eligible for analysis. This meta-analysis assessed 7 maternal and 11 newborn outcomes. Of these, gestational weight gain (GWG), fasting blood glucose (FBG), newborn birth weight, ponderal index (PI), proportion of macrosomia, and large for gestational age (LGA) were investigated in more than 8 trials. Compared with control diets, low-GI diets significantly reduced FBG (weight mean differences (WMD) = −0.18 mmol/L, 95 % CI: −0.33, −0.02), 2-h postprandial glucose level (WMD = −0.33 mmol/L, 95 % CI: −0.54, −0.12), and the proportion of LGA (RR = 0.52, 95 % CI: 0.31, 0.89). A lower GWG (WMD = −0.69 kg, 95 % CI: −1.74, 0.36) and birth weight (WMD = −0.10 kg, 95 % CI: −0.23, 0.03) were also observed without significant differences. Heterogeneity was observed in the GWG, FBG, and birth weight analyses. Low-GI diets did not affect other maternal and newborn outcomes. In subgroup and sensitivity analyses, the intervention effects of low GI on GWG and FBG varied.Low-GI diets may have beneficial effects on maternal outcomes for those at risk of developing high glucose levels, without causing adverse effects on newborn outcomes. However, results should be interpreted with caution because of the evidence of heterogeneity and limited number of studies.
Keywords: Low glycemic index; Pregnancy outcomes; Randomized controlled trials; Meta-analysis
The amount and types of fatty acids acutely affect insulin, glycemic and gastrointestinal peptide responses but not satiety in metabolic syndrome subjects by Chee-Yan Chang; M. S. Kanthimathi; Alexander Tong-Boon Tan; Kalanithi Nesaretnam; Kim-Tiu Teng (179-190).
Limited clinical evidence is available on the effects of amount and types of dietary fats on postprandial insulinemic and gastrointestinal peptide responses in metabolic syndrome subjects. We hypothesized that meals enriched with designated: (1) amount of fats (50 vs 20 g), (2) fats with differing fatty acid composition (saturated, SFA; monounsaturated, MUFA or n-6 polyunsaturated fatty acids, PUFA) would affect insulinemic and gastrointestinal peptide releases in metabolic syndrome subjects.Using a randomized, crossover and double-blinded design, 15 men and 15 women with metabolic syndrome consumed high-fat meals enriched with SFA, MUFA or n-6 PUFA, or a low-fat/high-sucrose (SUCR) meal. C-peptide, insulin, glucose, gastrointestinal peptides and satiety were measured up to 6 h.As expected, SUCR meal induced higher C-peptide (45 %), insulin (45 %) and glucose (49 %) responses compared with high-fat meals regardless of types of fatty acids (P < 0.001). Interestingly, incremental area under the curve (AUC0-120min) for glucagon-like peptide-1 was higher after SUCR meal compared with MUFA (27 %) and n-6 PUFA meals (23 %) (P = 0.01). AUC0-120min for glucose-dependent insulinotropic polypeptide was higher after SFA meal compared with MUFA (23 %) and n-6 PUFA meals (20 %) (P = 0.004). Significant meal x time interaction (P = 0.007) was observed for ghrelin, but not cholecystokinin and satiety.The amount of fat regardless of the types of fatty acids affects insulin and glycemic responses. Both the amount and types of fatty acids acutely affect the gastrointestinal peptide release in metabolic syndrome subjects, but not satiety.
Keywords: Metabolic syndrome; Fatty acids; Gastrointestinal peptides; Insulinemic; Postprandial
Anthropometrically predicted visceral adipose tissue and blood-based biomarkers: a cross-sectional analysis by Justin C. Brown; Michael O. Harhay; Meera N. Harhay (191-198).
We hypothesized that anthropometrically predicted visceral adipose tissue (apVAT) accounts for more variance in blood-based biomarkers of glucose homeostasis, inflammation, and lipid metabolism than body mass index (BMI), waist circumference (WC), and the combination of BMI and WC (BMI + WC).This was a cross-sectional analysis of 10,624 males and females who participated in the Third National Health and Nutrition Examination Survey (NHANES III; 1988–1994). apVAT was predicted from a validated regression equation that included age, height, weight, waist, and thigh circumferences. Bootstrapped linear regression models were used to compare the proportion of variance (R 2) in biomarkers explained by apVAT, BMI, WC, and BMI + WC.apVAT accounted for more variance in biomarkers of glucose homeostasis than BMI (∆R 2 = 8.4–11.8 %; P < 0.001), WC (∆R 2 = 5.5–8.4 %; P < 0.001), and BMI + WC (∆R 2 = 5.1–7.7 %; P < 0.001). apVAT accounted for more variance in biomarkers of inflammation than BMI (ΔR 2 = 3.8 %; P < 0.001), WC (ΔR 2 = 3.1 %; P < 0.001), and BMI + WC (ΔR 2 = 2.9 %; P < 0.001). apVAT accounted for more variance in biomarkers of lipid metabolism than BMI (ΔR 2 = 2.9–9.2 %; P < 0.001), WC (ΔR 2 = 2.9–5.2 %; P < 0.001), and BMI + WC (ΔR 2 = 2.4–4.1 %; P ≤ 0.01).apVAT, estimated with simple and widely used anthropometric measures, accounts for more variance in blood-based biomarkers than BMI, WC, and BMI + WC. Clinicians and researchers may consider utilizing apVAT to characterize cardio-metabolic health, particularly in settings with limited availability of imaging and laboratory data.
Keywords: Adiposity; Body composition; Waist–hip ratio; Population-based
Glyceamic and insulinaemic response to mashed potato alone, or with broccoli, broccoli fibre or cellulose in healthy adults by Simon Ballance; Svein Halvor Knutsen; Øivind Winther Fosvold; Martin Wickham; Carmen Díaz-Toledo Trenado; John Monro (199-207).
To examine the role of realistic serving sizes of broccoli, broccoli fibre and cellulose co-consumed with mash potato, or mashed potato eaten alone, on glycaemic and insulinaemic responses (GR and IR) in healthy adults.A non-blind randomized crossover trial was conducted with thirteen healthy subjects consuming four different meals. Capillary blood samples between 0 and 180 min were analysed for glucose and insulin. The incremental area under the fasting blood glucose and insulin curves (iAUC) was calculated for different time increments. Differences in GR and IR between meals were assessed by repeated measures analysis of variance.The immediate GR and IR to one serving of mashed potato eaten with two servings of broccoli were significantly lower than mashed potato eaten alone. The peak, incremental peak and iAUC0–30min for GR and iAUC0–30min for IR were all significantly lower for the broccoli–potato meal. This meal also takes longer to return to fasting baseline with a time-delayed lag in IR and GR compared to the potato only meal. The iAUC60–120min for IR was significantly greater for the broccoli–potato meal compared to the other meals. Yet there was no corresponding significant difference between the broccoli–potato meal and the other meals for peak, incremental peak IR or any other iAUCs for GR and IR. For the potato meals containing added broccoli fibre or cellulose, no significant differences in GR or IR were observed when compared with the potato eaten alone.Co-consumption of cooked broccoli with mashed potato has a significant effect on glycaemic and insulinaemic responses compared to potato eaten alone. Our study suggests broccoli eaten with potato improves glucose homeostasis and therefore indicates a general beneficial nutritional role for broccoli when eaten with a carbohydrate staple.
Keywords: Blood sugar; Vegetable; Starch; Meal; Carbohydrate staple
Maternal diet during pregnancy and micronuclei frequency in peripheral blood T lymphocytes in mothers and newborns (Rhea cohort, Crete) by Cristina O’Callaghan-Gordo; Manolis Kogevinas; Marie Pedersen; Eleni Fthenou; Ana Espinosa; Xristina Tsiapa; Georgia Chalkiadaki; Vasiliki Daraki; Eirini Dermitzaki; Ilse Decordier; Peter B. Farmer; Panagiotis Georgiadis; Vaggelis Georgiou; Soterios A. Kyrtopoulos; Domenico Franco Merlo; Dora Romaguera; Theano Roumeliotaki; Katerina Sarri; Margareta Törnqvist; Kim Vande Loock; Hans von Stedingk; Jos Kleinjans; Micheline Kirsch-Volders; Leda Chatzi (209-218).
The study assessed whether diet and adherence to cancer prevention guidelines during pregnancy were associated with micronucleus (MN) frequency in mothers and newborns. MN is biomarkers of early genetic effects that have been associated with cancer risk in adults.A total of 188 mothers and 200 newborns from the Rhea cohort (Greece) were included in the study. At early-mid pregnancy, we conducted personal interviews and a validated food frequency questionnaire was completed. With this information, we constructed a score reflecting adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention guidelines on diet, physical activity and body fatness. At delivery, maternal and/or cord blood was collected to measure DNA and hemoglobin adducts of dietary origin and frequencies of MN in binucleated and mononucleated T lymphocytes (MNBN and MNMONO).In mothers, higher levels of red meat consumption were associated with increased MNBN frequency [2nd tertile IRR = 1.34 (1.00, 1.80), 3rd tertile IRR = 1.33 (0.96, 1.85)] and MNMONO frequency [2nd tertile IRR = 1.53 (0.84, 2.77), 3rd tertile IRR = 2.69 (1.44, 5.05)]. The opposite trend was observed for MNBN in newborns [2nd tertile IRR = 0.64 (0.44, 0.94), 3rd tertile IRR = 0.68 (0.46, 1.01)], and no association was observed with MNMONO. Increased MN frequency in pregnant women with high red meat consumption is consistent with previous knowledge.Our results also suggest exposure to genotoxics during pregnancy might affect differently mothers and newborns. The predictive value of MN as biomarker for childhood cancer, rather than adulthood, remains unclear. With few exceptions, the association between maternal carcinogenic exposures during pregnancy and childhood cancer or early biologic effect biomarkers remains poorly understood.
Keywords: Maternal nutrition; Cancer; Genotoxicity; Diet; Epidemiology
Rice bran protein hydrolysates reduce arterial stiffening, vascular remodeling and oxidative stress in rats fed a high-carbohydrate and high-fat diet by Ketmanee Senaphan; Weerapon Sangartit; Poungrat Pakdeechote; Veerapol Kukongviriyapan; Patchareewan Pannangpetch; Supawan Thawornchinsombut; Stephen E. Greenwald; Upa Kukongviriyapan (219-230).
Rice bran protein hydrolysates (RBPH) contain highly nutritional proteins and antioxidant compounds which show benefits against metabolic syndrome (MetS). Increased arterial stiffness and the components of MetS have been shown to be associated with an increased risk of cardiovascular disease. This study aimed to investigate whether RBPH could alleviate the metabolic disorders, arterial stiffening, vascular remodeling, and oxidative stress in rats fed a high-carbohydrate and high-fat (HCHF) diet.Male Sprague–Dawley rats were fed either a standard chow and tap water or a HCHF diet and 15 % fructose solution for 16 weeks. HCHF rats were treated orally with RBPH (250 or 500 mg/kg/day) for the final 6 weeks of the experimental period.Rats fed with HCHF diet had hyperglycemia, insulin resistance, dyslipidemia, hypertension, increased aortic pulse wave velocity, aortic wall hypertrophy and vascular remodeling with increased MMP-2 and MMP-9 expression. RBPH supplementation significantly alleviated these alterations (P < 0.05). Moreover, RBPH reduced the levels of angiotensin-converting enzyme (ACE) and tumor necrosis factor-alpha in plasma. Oxidative stress was also alleviated after RBPH treatment by decreasing plasma malondialdehyde, reducing superoxide production and suppressing p47phox NADPH oxidase expression in the vascular tissues of HCHF rats. RBPH increased plasma nitrate/nitrite level and up-regulated eNOS expression in the aortas of HCHF-diet-fed rats, indicating that RBPH increased NO production.RBPH mitigate the deleterious effects of HCHF through potential mechanisms involving enhanced NO bioavailability, anti-ACE, anti-inflammatory and antioxidant properties. RBPH could be used as dietary supplements to minimize oxidative stress and vascular alterations triggered by MetS.
Keywords: Arterial stiffness; High-carbohydrate and high-fat diet; Metabolic syndrome; Rice bran protein hydrolysates; Oxidative stress; Vascular remodeling
Catabolism of citrus flavanones by the probiotics Bifidobacterium longum and Lactobacillus rhamnosus by Gema Pereira-Caro; Begoña Fernández-Quirós; Iziar A Ludwig; Inmaculada Pradas; Alan Crozier; José Manuel Moreno-Rojas (231-242).
Orange juice (OJ) flavanones undergo limited absorption in the upper gastrointestinal tract and reach the colon where they are transformed by the microbiota prior to absorption. This study investigated the ability of two probiotic bacteria, Bifidobacterium longum R0175 and Lactobacillus rhamnosus subsp. Rhamnosus NCTC 10302 to catabolise OJ flavanones.The bacteria were incubated with hesperetin-7-O-rutinoside, naringenin-7-O-rutinoside, hesperetin and naringenin, and the culture medium and intracellular cell extracts were collected at intervals over a 48 h of incubation period. The flavanones and their phenolic acid catabolites were identified and quantified by HPLC–HR–MS.Both probiotics were able to subject hesperetin to ring fission yielding 3-(3′-hydroxy-4′-methoxyphenyl)propionic acid which was subsequently demethylated producing 3-(3′,4′-dihydroxyphenyl)propionic acid and then via successive dehydroxylations converted to 3-(3′-hydroxyphenyl)propionic acid and 3-(phenyl)propionic acid. Incubation of both bacteria with naringenin resulted in its conversion to 3-(4′-hydroxyphenyl)propionic acid which underwent dehydroxylation yielding 3-(phenyl)propionic acid. In addition, only L. rhamnosus exhibited rhamnosidase and glucosidase activity and unlike B. longum, which was able to convert hesperetin-7-O-rutinoside and naringenin-7-O-rutinoside to their respective aglycones. The aglycones were then subjected to ring fission and further catabolised in a similar manner to that described above. The flavanones and their catabolites were found in the culture medium but not accumulated in the bacterial cells.These findings demonstrate the enzymatic potential of single strains of bifidobacterium and lactobacillus which may be involved in the colonic catabolism of OJ flavanones in vivo.
Keywords: Bifidobacterium longum R0175; Lactobacillus rhamnosus subsp. Rhamnosus NCTC 10302; Probiotics; Flavanones; In vitro incubation; Bacterial catabolism
Dietary fat and carbohydrate quality have independent effects on postprandial glucose and lipid responses by Lijuan Sun; Kevin Wei Jie Tan; Joseph Zhien Lim; Faidon Magkos; Christiani Jeyakumar Henry (243-250).
The magnitude of postprandial lipemia is influenced not only by the amount but also the type of fat and carbohydrate consumed. The aim of this study was to evaluate differences in postprandial glucose and lipid responses after a mixed meal containing low- or high-glycemic-index (GI) carbohydrate and three different types of fat varying in the degree of saturation in healthy subjects. A randomized, controlled, single-blinded crossover study was conducted in 20 healthy Chinese men. Subjects consumed in random order six experimental isocaloric meals that differed in carbohydrate and fat quality, and contained 40 g of either saturated fat (SFA, butter), monounsaturated fat (MUFA, olive oil) or polyunsaturated fat (PUFA, grapeseed oil), and 50 g of either low-GI (basmati rice) or high-GI (jasmine rice) carbohydrate. Glucose, insulin, c-peptide, triglycerides (TG) and non-esterified fatty acids (NEFA) were measured over 4 h.For all substrates evaluated, there were no significant interactions between fat and carbohydrate. The incremental area under the curve (iAUC) for TG was significantly lower after the SFA and PUFA meals compared with the MUFA meal, irrespective of GI. No significant difference was found for NEFA iAUC in all treatments. Glucose, insulin and c-peptide iAUCs were significantly lower after ingestion of low-GI than high-GI meals, independent of the type of fat.A carbohydrate-rich meal (of either low or high GI) that contains butter or grapeseed oil results in lower postprandial TG concentrations relative to olive oil in healthy Chinese males. Glucose, insulin and c-peptide responses, however, are directly dependent on the GI of the meal and not on the degree of saturation of dietary fat.The trial was registered at clinicaltrials.gov as NCT02585427.
Keywords: Dietary fat; Carbohydrate; Postprandial response; Mixed meal; Rice
Consumption of a drink containing extruded sorghum reduces glycaemic response of the subsequent meal by Pamella Cristine Anunciação; Leandro de Morais Cardoso; Valéria Aparecida Vieira Queiroz; Cicero Beserra de Menezes; Carlos Wanderlei Piler de Carvalho; Helena Maria Pinheiro-Sant’Ana; Rita de Cássia Gonçalves Alfenas (251-257).
Glycaemic control is essential to prevent the manifestation of diabetes in predisposed individuals and the development of associated comorbidities. It is believed that sorghum may modulate the glucose response. In this study, we investigated the effect of extruded sorghum consumption, and the profile of bioactive compounds, on postprandial glycaemia of a subsequent meal in normal weight and normoglycaemic subjects.This was a randomized, single-blind, crossover designed study. After a 12 h overnight fasting, ten subjects reported to the laboratory to participate in four experimental sessions, and consumed one of three sorghum test drinks: sorghum P 3-DXAs (with proanthocyanidins—P and rich in 3-deoxyanthocyanidins—3-DXAs); 3-DXAs (without proanthocyanidins and rich in 3-DXAs); and control (low in 3-DXAs and without proanthocyanidins); or a non-sorghum drink. 30 min later, the subjects consumed a glucose solution (25 g glucose). Glycaemic response was monitored at times 0 (before glucose solution), 15, 30, 45, 60, 90, 120 min (after glucose solution consumption). The incremental areas under the glycaemic curve (iAUC) were calculated by the trapezoidal method.Intake of P 3-DXAs drink before the glucose solution resulted in a postprandial iAUC lower than the other sorghum test drinks. Sorghum drinks minimized the postprandial glycaemia peak.Sorghum drinks consumption, especially the P 3-DXAs drink, 30 min before the glucose solution resulted in lower iAUC compared to the non-sorghum drink, leading to a lower glycaemic response.
Keywords: Diabetes mellitus; Glycaemic response; Sorghum; Food and beverages
Controlling type-2 diabetes by inclusion of Cr-enriched yeast bread in the daily dietary pattern: a randomized clinical trial by Amalia E. Yanni; Nikoleta S. Stamataki; Panagiotis Konstantopoulos; Maria Stoupaki; Athanasios Abeliatis; Irene Nikolakea; Despoina Perrea; Vaios T. Karathanos; Nikolaos Tentolouris (259-267).
Chromium (Cr)-enriched yeast supplementation to whole wheat bread (WWCrB) has been shown to ameliorate postprandial glycemic response in healthy subjects. The present study investigates the long-term benefit of WWCrB consumption for patients with type-2 diabetes mellitus (T2DM).Thirty patients with T2DM were randomly assigned to a group receiving WWCrB or the plain whole wheat bread (WWB) group. Plasma glucose, insulin, glycosylated hemoglobin (HbA1c) and insulin resistance were determined, and oral glucose tolerance test (OGTT) was performed at the beginning and the end of the dietary intervention, which lasted for 12 weeks. Biochemical parameters related to the disease, markers of inflammation as well as body weight and energy balance were examined.At the end of the study, subjects of WWCrB group exerted lower levels of glucose, insulin and HbA1c and improved insulin resistance (P < 0.05 against before treatment). Area under the glucose curve attained during OGTT decreased after the intervention (28,117.5 ± 1266.4 vs. 31,588.5 ± 1187.5 mg min/dL before treatment, P < 0.05) with significantly lower values of glucose concentration at 0 and 60 min. A significant reduction in body weight and systolic blood pressure (SBP) was observed (P < 0.05 against before treatment). Markers of inflammation and lipid profiles were not affected by WWCrB consumption.Inclusion of WWCrB in the daily dietary pattern of diabetic patients resulted in improvement of glucose tolerance and insulin resistance, significant reduction in HbA1c, weight loss and lower SBP. Patients with inadequate glycemic control may benefit from the consumption of WWCrB.
Keywords: Bread; Type-2 diabetes mellitus; Cr-enriched yeast; Glucose tolerance; Insulin resistance; Weight management
Regularly consuming a green/roasted coffee blend reduces the risk of metabolic syndrome by Beatriz Sarriá; Sara Martínez-López; José Luis Sierra-Cinos; Luis García-Diz; Raquel Mateos; Laura Bravo-Clemente (269-278).
Preventive health effects of coffee could have a widespread impact on public health. Green coffee has more phenols than roasted, and thus is healthier, although with less acceptable organoleptic properties. Therefore, the effects of regularly consuming a green/roasted coffee blend (35/65) on the main components of MetS in humans were evaluated.A crossover, randomized, controlled study was performed in 25 normocholesterolaemic and 27 hypercholesterolaemic men and women aged 18–45 years with BMI 18–25 kg/m2. Three servings/day of the blend, providing 510.6 mg hydroxycinnamic acids and 121.2 mg caffeine/day, were consumed versus a control drink, during 8 weeks each. Polyphenol and methylxanthine-rich foods were restricted along the study. At the beginning (baseline) and end of the control and coffee interventions, blood samples were collected and glucose, HDL-cholesterol, triglycerides, insulin, leptin, plasminogen activator inhibitor-1 (PAI-1), resistin and visfatin were analysed; waist circumference, %body fat, and blood pressure were measured and dietary records and physical activity questionnaires completed.Systolic and diastolic blood pressure decreased (p = 0.001 and p < 0.001, respectively) in both groups as well as %body fat (p = 0.001) which may be related to the lower leptin (p = 0.001), PAI-1 (p < 0.001) and resistin (p = 0.034) levels in the two groups after coffee consumption. Glucose concentration (p = 0.030) and insulin resistance (p = 0.011; HOMA-IR) also decreased, as well as triglyceride levels (p = 0.017), so that the reduction was much greater in the hypercholesterolaemics (group effect, p = 0.027).Regular consumption of the green/roasted coffee blend may be recommended to healthy and hypercholesterolaemic subjects to prevent MetS, as it produces positive effects on blood pressure, glucose and triglyceride levels.
Keywords: Coffee; Hydroxycinnamic acids; Diabetes; Hypertension; Weight loss; Metabolic syndrome
Improvement in glucose tolerance and insulin sensitivity by probiotic strains of Indian gut origin in high-fat diet-fed C57BL/6J mice by Mahalingam Balakumar; Durai Prabhu; Chandrakumar Sathishkumar; Paramasivam Prabu; Namita Rokana; Ramesh Kumar; Srividhya Raghavan; Avinash Soundarajan; Sunita Grover; Virender Kumar Batish; Viswanathan Mohan; Muthuswamy Balasubramanyam (279-295).
Diabetes and obesity are characterized by glucose intolerance, fat deposition, inflammation, and dyslipidemia. Recent reports postulated that distinct gut microbiota alterations were observed in obese/diabetic subjects and modulating gut microbiota beneficially through specific probiotics could be a potential therapeutic option for type 2 diabetes/obesity. Therefore, we attempted to study the efficacy of probiotics of Indian gut origin (Lactobacillus plantarum MTCC5690 and Lactobacillus fermentum MTCC5689) along with a positive control, Lactobacillus rhamnosus (LGG) on glucose/lipid homeostasis in high-fat-diet-induced diabetic animal model.C57BL/6J male mice were divided into seven groups (n = 6 per group) comprising feeding on: (1) Normal Pellet Diet (NPD), (2) High-Fat Diet (HFD), (3) HFD with LGG, (4) HFD with MTCC5690, (5) HFD with MTCC5689, (6) HFD with metformin, and 7) HFD with vildagliptin for a period of 6 months. Biochemical markers, glucose tolerance, insulin resistance, and GLP-1 and LPS levels were assessed by standard protocols. Gut integrity was measured by intestinal permeability test. Transcriptional levels of tight junction proteins (TJPs) were probed in small intestinal tissues while inflammatory signals and other pathway specific genes were profiled in liver, visceral adipose tissue, and skeletal muscle.Mice fed with HFD became insulin resistant, glucose intolerant, hyperglycemic, and dyslipidemic. Diabetic mice were characterized to exhibit decreased levels of GLP-1, increased gut permeability, increased circulatory levels of LPS, decrease in the gene expression patterns of intestinal tight junction markers (occludin and ZO-1), and increased proinflammatory gene markers (TNFα and IL6) in visceral fat along with decreased mRNA expression of FIAF and adiponectin. Diabetic mice also exhibited increased mRNA expression of ER stress markers in skeletal muscle. In addition, liver from HFD-fed diabetic mice showed increased gene expressions of proinflammation, lipogenesis, and gluconeogenesis. Probiotic interventions (most prominently the MTCC5689) resisted insulin resistance and development of diabetes in mice under HFD feeding and beneficially modulated all the biochemical and molecular alterations in a mechanistic way in several tissues. The metabolic benefits offered by the probiotics were also more or less similar to that of standard drugs such as metformin and vildagliptin.Native probiotic strains MTCC 5690 and MTCC 5689 appear to have potential against insulin resistance and type 2 diabetes with mechanistic, multiple tissue-specific mode of actions.
Keywords: Type 2 diabetes; Insulin resistance; Probiotics; High-fat diet; Tight junction protein; LPS; Lactobacillus plantarum MTCC 5690; Lactobacillus fermentum MTCC 5689; LGG
Identification of urinary metabolites with potential blood pressure-lowering effects in lentil-fed spontaneously hypertensive rats by Matthew Hanson; Peter Zahradka; Carla G. Taylor; Michel Aliani (297-308).
Urine samples were obtained from a previously completed study that showed lentil consumption attenuates the increase in blood pressure that occurs over time in spontaneously hypertensive rats (SHRs). The objective of the present study was to compare the metabolite profile of the urine samples from control and lentil-fed SHR in relation to the compounds present in lentils but not in other pulses.The urine samples were from 17-week-old, male SHR fed semi-purified diet prepared with powder (30 %, w/w) from cooked whole pulses or a pulse-free control diet (n = 8/group) for 4 weeks. Pulse powders, control diet and urine samples were extracted using acetonitrile and analyzed by a high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF-MS).Twenty-seven metabolites were significantly different in urine samples from lentil-fed SHR compared to SHR fed control diet, but only 7 were not present in the urine of SHR fed other pulses. Of these metabolites, only citrulline is linked to blood pressure regulation via production of the vasodilator nitric oxide (NO). Several arginine-related compounds that are NO synthase substrates or inhibitors were detected in lentils but not the control diet or other pulse powders.Consumption of lentils increases the availability of arginine and several related compounds that could potentially elevate production of NO and contribute to the blood pressure-lowering effects of lentil-rich diets.
Keywords: Hypertension; Metabolomics; Spontaneously hypertensive rat; Lentils
The repeatability of the abbreviated (4-h) Oral Fat Tolerance Test and influence of prior acute aerobic exercise by A. F. O’Doherty; T. Sathyapalan; A. S. Rigby; L. Ingle; S. Carroll (309-318).
The Oral Fat Tolerance Test (OFTT) is regarded as a repeatable measure used to assess postprandial triglyceride (TAG) levels, with higher levels observed in cardio-metabolic disorders. Acute aerobic exercise intervention before OFTT reduces the TAG response, but the repeatability of this effect is unknown. The aim of this study was to determine the repeatability of the abbreviated 4-h OFTT with and without immediate prior aerobic exercise.On four separate days, healthy adult male participants underwent two 4-h OFTT (n = 10) and another two 4-h OFTT with 1-h of standardised moderate intensity aerobic exercise performed immediately before meal ingestion (n = 11). The OFTT meal composition included 75.4 g total fat, 21.7 g carbohydrate and 13.7 g protein. Venous blood was sampled at baseline and hourly up to 4 h after the OFTT meal ingestion, and TAG area under the curve (AUC) was calculated.Nonparametric Bland–Altman analysis of 4-h TAG AUC revealed that 9 of 10 repeat measurements fell within ±15 % of the median TAG AUC for the OFTT. By contrast, two of 11 repeat measurements fell within ±15 % of the median TAG AUC for the OFTT undertaken with 1-h prior aerobic exercise.The 4-h OFTT is a repeatable test of postprandial TAG responses in healthy men. However, aerobic exercise performed immediately before OFTT considerably increases the variability of TAG AUC. These findings have implications for interpretation of research studies investigating exercise intervention performed immediately before OFTT. Future studies should also investigate the repeatability of exercise performed 8–24 h before OFTT.
Keywords: OFTT; Postprandial metabolism; Acute exercise; Lipids; Repeatability
Durum wheat particle size affects starch and protein digestion in vitro by Giuseppina Mandalari; Zara Merali; Peter Ryden; Simona Chessa; Carlo Bisignano; Davide Barreca; Ersilia Bellocco; Giuseppina Laganà; Richard M. Faulks; Keith W. Waldron (319-325).
The term bioaccessibility refers to the proportion of a nutrient released from a complex food matrix during digestion and, therefore, becoming potentially available for absorption in the gastrointestinal tract. In the present study, we assessed the starch and protein bioaccessibility from a range of wheat endosperm products differing in particle size.Five porridge meals (size A, flour, mean particle size 0.11 mm, size B, small, mean particle size 0.38 mm, size C, semolina, mean particle size 1.01 mm, size D, medium, mean particle size 1.44 mm, size E, large, mean particle size 1.95 mm) with theoretically different postprandial glycaemic responses were subjected to oral processing in vitro, followed by simulated gastric and duodenal digestion.A significant increase (P < 0.001) in starch degradation was observed in size A (52%) compared with size E (25%). Both sizes C and D gave less, although not significantly, digestible starch (32 and 28%, respectively). The glucose release significantly decreased as the particle size of the meal increased (92.16% detected for size A vs 47.39% for size E). In agreement with starch degradation and glucose release, size A gave the most digestible protein.This data provide further evidence that, by decreasing the size of wheat endosperm, starch release and glycaemic response are enhanced. We also showed that protein bioaccessibility followed a similar trend as for starch digestion. Finally, these results support the hypothesis that different degrees of starch encapsulation elicit different blood glucose responses.
Keywords: Starch digestion; In vitro models; Wheat endosperm; Glycaemic response
N-acetylcysteine attenuates intrauterine growth retardation-induced hepatic damage in suckling piglets by improving glutathione synthesis and cellular homeostasis by Hao Zhang; Weipeng Su; Zhixiong Ying; Yueping Chen; Le Zhou; Yue Li; Jingfei Zhang; Lili Zhang; Tian Wang (327-338).
The objective of the present study was to test the hypothesis that N-acetylcysteine (NAC) may play beneficial roles against intrauterine growth retardation (IUGR)-induced hepatic damage in suckling piglets.Fourteen IUGR and seven normal birth weight (NBW) neonatal male piglets were selected. Piglets were weaned at 7 days of postnatal age and fed the control formula milk (NBW-CON and IUGR-CON groups) or the control formula milk supplemented with 1.2 g/kg NAC (IUGR-NAC group) for 14 days (n = 7). The plasma and liver samples were analyzed for the parameters related to hepatic damage, redox status, apoptosis, and autophagy.Compared with the NBW-CON group, IUGR-CON group exhibited increased activities of plasma aminotransferases, increased numbers of apoptotic hepatocytes, as well as higher concentrations of protein carbonyl, malondialdehyde (MDA), microtubule-associated protein 1 light chain 3 beta, and phospholipid-conjugated form (MAP1LC3B-II), along with a decrease in the content of reduced glutathione (GSH). NAC treatment increased GSH content and GSH-to-oxidized GSH ratio in the liver of IUGR-NAC group, most likely owing to the improved activities of γ-glutamine-cysteine ligase, γ-glutamine-cysteine synthetase, and glutathione reductase. The hepatic protein carbonyl and MDA contents were decreased in the IUGR-NAC group compared with the IUGR-CON group. In addition, NAC-treated piglets had an increased content of B cell lymphoma/leukemia 2 protein, whereas a decreased expression level of MAP1LC3B-II in the liver.NAC may have beneficial effects in improving GSH synthesis and cellular homeostasis in the liver of IUGR suckling piglets.
Keywords: Intrauterine growth retardation; N-acetylcysteine; Oxidative stress; Glutathione synthesis; Cellular homeostasis; Piglet
A high-fat high-sucrose diet affects the long-term metabolic fate of grape proanthocyanidins in rats by Eunice Molinar-Toribio; Elisabet Fuguet; Sara Ramos-Romero; Núria Taltavull; Lucía Méndez; M. Rosa Nogués; Isabel Medina; Josep Lluís Torres; Jara Pérez-Jiménez (339-349).
Polyphenol metabolites are key mediators of the biological activities of polyphenols. This study aimed to evaluate the long-term effects of a high-fat high-sucrose (HFHS) diet on the metabolism of proanthocyanidins from grape seed extract (GSE).Adult female Wistar–Kyoto rats were fed a standard (STD) or HFHS diet supplemented or not with GSE for 16 weeks. PA metabolites were determined by targeted HPLC–MS/MS analysis.A lower concentration of total microbial-derived PA metabolites was present in urine and the aqueous fraction of faeces in the HFHS + GSE group than in the STD + GSE group. In contrast, a tendency towards the formation of conjugated (epi)catechin metabolites in the HFHS + GSE group was observed.These results show that a HFHS diet significantly modifies PA metabolism, probably via: (1) a shift in microbial communities not counteracted by the polyphenols themselves; and (2) an up-regulation of hepatic enzymes.
Keywords: Polyphenols; Proanthocyanidins; High-fat high-sucrose diet; Bioavailability; Metabolites
Dietary energy density and obesity: how consumption patterns differ by body weight status by Jacqueline A. Vernarelli; Diane C. Mitchell; Barbara J. Rolls; Terryl J. Hartman (351-361).
Recent public health messages have advised consumers to lower dietary energy density (ED) for weight management, but it is not known whether the proportion of the diet from low-ED foods is related to weight status. In a nationally representative sample of US adults, we evaluated whether the proportions of dietary energy intake contributed by low- and high-ED foods are associated with body mass index (BMI) and waist circumference (WC).Data were from a cross-sectional sample of 9551 adults ≥18 years in the 2005–2008 National Health and Nutrition Examination Survey (NHANES). ED (kcal/g) was calculated for each food item reported during a 24-h dietary recall; individual foods were divided into five ED categories: very low ED (<0.6 kcal/g), low ED (0.6–1.5 kcal/g), medium ED (1.51–2.25 kcal/g), high ED (2.26–4.0 kcal/g), and very high ED (>4.0 kcal/g). The percentages of total energy and the food weight from each category were evaluated by BMI and WC after controlling for total energy intake and other covariates.Men classified as lean (BMI < 25 kg/m2) reported consuming a greater proportion of total energy from very low- and low-ED foods (7.2 %very low and 23.3 %low), compared to men considered obese ((BMI > 30 kg/m2); 5.2 %very low and 20.1low %; p-trends <0.001very low, 0.002low). Similarly, women classified as lean reported intakes of very low-ED foods of 7.8 % (vs. 6.4 % for women with obesity) of total energy and low-ED foods of 24.7 % (vs. 21.5 % for women with obesity) of total energy (p-trends 0.007very low, 0.004low). Men and women with obesity reported greater proportions of energy from high-ED foods (45.9 %men with obesity vs. 42.4 %lean men, 44.2 %women with obesity vs. 39.9 %lean women) with significant statistical trends (men = 0.008, women = 0.0005). Similar patterns were observed for intakes of proportions of very low-, low-, and high-ED foods and WC.Higher proportions of energy intake and food weight contributed by very low- and low-ED foods are associated with lower BMI (and WC).
Keywords: Energy density; Fruits and vegetables; NHANES; Waist circumference; Body mass index; Obesity
Diet quality and telomere length in older Australian men and women by Catherine M. Milte; Aaron P. Russell; Kylie Ball; David Crawford; Jo Salmon; Sarah A. McNaughton (363-372).
Telomere length is a biomarker of cellular ageing, with longer telomeres associated with longevity and reduced risk of chronic disease in older age. Consumption of a healthy diet may contribute to longevity via its impact on cellular ageing, but studies on diet and telomere length to date have been limited and their findings equivocal. The aim of this study was to examine associations between three indices of diet quality and telomere length in older men and women.Adults aged 57–68 years participating in the Wellbeing, Eating and Exercise for a Long Life (WELL) study in Victoria, Australia (n = 679), completed a postal survey including an 111-item food frequency questionnaire in 2012. Diet quality was assessed via three indices: the Dietary Guideline Index, the Recommended Food Score, and the Mediterranean Diet Score. Relative telomere length was measured by quantitative polymerase chain reaction. Associations between diet quality and telomere length were assessed using linear regression adjusted for covariates.After adjustment for age, sex, education, smoking, physical activity, and body mass index (BMI), there were no significant associations between diet quality and relative telomere length.In a sample of older adults residing in Victoria, Australia, men and women aged 57–68 years with better-quality diets did not have longer telomeres. Further investigation in longitudinal studies will determine whether diet can influence telomere length over time in an ageing population.
Keywords: Diet; Ageing; Telomere length; Diet quality; Mediterranean diet
Associations between high birth weight, being large for gestational age, and high blood pressure among adolescents: a cross-sectional study by Renata Kuciene; Virginija Dulskiene; Jurate Medzioniene (373-381).
Low birth weight and being small for gestational age are associated with increased risk of cardiometabolic diseases. However, the results from the studies examining the associations between high birth weight (HBW), being large for gestational age (LGA), and high blood pressure (HBP) are inconsistent. The aim of this study was to evaluate the associations between HBW and being LGA alone and in combinations with body mass index (BMI) categories in adolescence and HBP among Lithuanian adolescents aged 12–15 years.The participants with HBP (≥90th percentile) were screened on two separate occasions. Data on the BMI, birth weight (BW), gestational age, and BP were analyzed in 4598 adolescents. Adjusted odds ratios (aORs) with 95% confidence intervals (CI) for the associations were estimated using multivariate logistic regression models.The overall prevalence of HBW (>4000 g), being LGA, adolescent overweight/obesity, and HBP were 13.9, 10.4, 14.5, and 25.6%, respectively. After adjustment for age, sex, and BMI, significant positive associations were found between HBW and being LGA and HBP (HBW: aOR 1.34; 95% CI, 1.11–1.63; LGA: aOR 1.44; 95% CI, 1.16–1.79). After adjustment for age and sex and compared to BW 2500–4000 g and being AGA (appropriate for gestational age) with normal weight in adolescence, the combinations that included both risk factors—HBW with overweight/obesity and being LGA with overweight/obesity—showed higher aORs (aOR 4.36; 95% CI, 3.04–6.26; and aOR 5.03; 95% CI, 3.33–7.60, respectively) than those with either of these risk factors alone did.HBW and being LGA were positively associated with HBP in Lithuanian adolescents aged 12–15 years. The highest odds of having HBP were observed for subjects with both risk factors—neonatal HBW or being LGA and overweight/obesity in adolescence.
Keywords: High blood pressure; High birth weight; Large for gestational age; Overweight; Obesity; Adolescents
Daily supplementation with fresh pomegranate juice increases paraoxonase 1 expression and activity in mice fed a high-fat diet by D. Estrada-Luna; E. Martínez-Hinojosa; J. C. Cancino-Diaz; H. Belefant-Miller; G. López-Rodríguez; G. Betanzos-Cabrera (383-389).
Studies have found that pomegranate juice (PJ) consumption increases the binding of high-density lipoproteins (HDL) to paraoxonase 1 (PON1), thus increasing the catalytic activity of this enzyme. PON1 is an antioxidant arylesterase synthesized in the liver and transported in plasma in association with HDL. Decreased levels of PON1 are associated with higher levels of cholesterol. We determined the effects of PJ on body weight, cholesterol, and triacylglycerols through 5 months of supplementation. In addition, the effect of PJ on pon1 gene expression in the liver was also measured by RT-qPCR as well as the activity in serum by a semiautomated method using paraoxon as a substrate.CD-1 mice were either fed a control diet or were fed a high-fat diet 1.25% (wt/wt) cholesterol, 0.5% (wt/wt) sodium cholate, and 15% (wt/wt) saturated fat. 300 μL of PJ containing 0.35 mmol total polyphenols was administered by oral gavage to half of the high fat mice daily. The rest of the high fat mice and the control mice were administered with 300 μL of water.PJ-supplemented animals had significantly higher levels of expression of pon1 compared to the unsupplemented group. PJ-supplemented animals had twice the PON1 activity of the unsupplemented group. In addition, PJ-supplemented animals had the lowest body weight and significantly reduced cholesterol and triacylglycerol levels, although the tricylglycerol levels were not consistently decreased.These results suggest that PJ protects against the effects of a high-fat diet in body weight, and cholesterol levels.
Keywords: Pomegranate juice; Paraoxonase1; High-fat diet; Obesity
Myricetin-induced brown adipose tissue activation prevents obesity and insulin resistance in db/db mice by Tao Hu; Xiaoxue Yuan; Gang Wei; Haoshu Luo; Hyuek Jong Lee; Wanzhu Jin (391-403).
Myricetin, a dietary flavonoid, is effective in the treatment of obesity and insulin resistance by increasing glucose transport and lipogenesis in adipocyte and diminishing systemic inflammation in obesity. However, it has not been revealed yet whether myricetin is associated with brown adipose tissue (BAT) activation that tightly mediates systemic energy metabolism. Therefore, this study assessed whether myricetin activated brown adipose tissue in db/db mouse.Myricetin (400 mg/kg) in distilled water was fed daily by oral gavage to leptin receptor-deficient db/db male mice at 4 weeks of age for 14 weeks. Body weight change, glucose intolerance test, blood lipid profile and BAT activation using PET-CT were assessed.After myricetin treatment for 14 weeks, systemic insulin resistance and hepatic steatosis were significantly improved in db/db mice with body weight reduction and myricetin led to decreased adipocity, improved plasma lipid profiles and increased energy expenditure. Myricetin activated BAT by upregulating thermogenic protein expression and activating mitochondrial biogenesis, eventually increasing heat dissipation in skin after cold exposure. In iWAT, myricetin induced beige formation, increased thermogenic protein expression and activated mitochondrial biogenesis. Consistently, thermogenic gene expression was upregulated when myricetin was introduced in C3H10T1/2 cells during brown adipocytes differentiation. Moreover, the expression level of adiponectin was significantly increased in C3H10T1/2 cells, adipose tissues and plasma after myricetin treatment.These results highlight that myricetin prevents obesity and systemic insulin resistance by activating BAT and increasing adiponectin expression in BAT.
Keywords: Myricetin; Brown adipose tissue; Inguinal white adipose tissue; Obesity
Blackcurrant anthocyanins stimulated cholesterol transport via post-transcriptional induction of LDL receptor in Caco-2 cells by Bohkyung Kim; Minkyung Bae; Young-Ki Park; Hang Ma; Tao Yuan; Navindra P. Seeram; Ji-Young Lee (405-415).
We previously showed that polyphenol-rich blackcurrant extract (BCE) showed a hypocholesterolemic effect in mice fed a high fat diet. As direct cholesterol removal from the body via the intestine has been recently appreciated, we investigated the effect of BCE on the modulation of genes involved in intestinal cholesterol transport using Caco-2 cells as an in vitro model.Caco-2 cells were treated with BCE to determine its effects on mRNA and protein expression of genes important for intestinal cholesterol transport, low-density lipoprotein (LDL) uptake, cellular cholesterol content, and cholesterol transport from basolateral to apical membrane of Caco-2 cell monolayers. Cells were also treated with anthocyanin-rich or -poor fraction of BCE to determine the role of anthocyanin on BCE effects.BCE significantly increased protein levels of LDL receptor (LDLR) without altering its mRNA, which consequently increased LDL uptake into Caco-2 cells. This post-transcriptional induction of LDLR by BCE was markedly attenuated in the presence of rapamycin, an inhibitor of mechanistic target of rapamycin complex 1 (mTORC1). In addition, BCE altered genes involved in cholesterol transport in the enterocytes, including apical and basolateral cholesterol transporters, in such a way that could enhance cholesterol flux from the basolateral to apical side of the enterocytes. Indeed, BCE significantly increased the flux of LDL-derived cholesterol from the basolateral to the apical chamber of Caco-2 monolayer. LDLR protein levels were markedly increased by anthocyanin-rich fraction, but not by anthocyanin-free fraction.mTORC1-dependent post-transcriptional induction of LDLR by BCE anthocyanins drove the transport of LDL-derived cholesterol to the apical side of the enterocytes. This may represent a potential mechanism for the hypocholesterolemic effect of BCE.
Keywords: Blackcurrant; Caco-2 cells; Intestinal cholesterol excretion; LDL receptor
Association between lutein intake and lutein concentrations in human milk samples from lactating mothers in South Korea by Hyesook Kim; Hyunju Yi; Ji A. Jung; Namsoo Chang (417-421).
This study aimed to determine the lutein content of breast milk and its association with maternal lutein intake among lactating mothers in South Korea.Milk samples were obtained from 98 healthy lactating women (mean age; 32.5 ± 3.5 years). Dietary intake data were collected by a food record method for three consecutive days. Maternal lutein intake was estimated by using the lutein database. Lutein concentrations in human milk were analyzed using a high-performance liquid chromatography–ultraviolet detection method.The mean values of the daily lutein intakes and breast milk lutein concentrations in lactating mothers were 4.70 ± 3.11 mg/day (median 3.87) and 3.50 ± 3.71 µg/dl (median 2.45), respectively. Breast milk lutein concentrations were positively associated with the dietary lutein intake of lactating mothers after adjustment for lactating women’s age, BMI, dietary energy intake, type of breastfeeding, and infants’ age (β = 0.3629, P = 0.0056).Considering that lutein in milk can be associated with dietary lutein intake, knowledge about infant requirement is needed to define the adequate lutein levels in human milk.
Keywords: Lutein; dietary intake; human milk; lactating mothers