Water-soluble dietary fibers and cardiovascular disease

The association between homocysteine levels, Mediterranean diet and cardiovascular disease: a case-control study

The aim was to investigate the association between homocysteine (Hcy) and acute coronary syndrome (ACS) and to test the potential moderating role of Mediterranean diet. An age and gender matched case-control study was conducted among 1491 patients with a first ACS event and 3037 adults free of cardiovascular disease (CVD). Adherence to the Mediterranean diet was measured using the MedDietScore (range 0-55). An increase in Hcy levels was associated with a 1% and 3% higher likelihood of ACS among younger (<45 yrs) and middle-aged (45-60yrs) adults (p's < 0.05), but not in older adults (p = 0.13). Moreover, Hcy was associated with 3% (95%CI: 1.01-1.06) increase in the likelihood of ACS among those who did not adhere to the Mediterranean diet. Hence, Hcy is apparently independently associated with ACS among younger and middle-aged individuals. The inverse association between Mediterranean diet adherence and Hcy highlights a disease-preventing effect of the Mediterranean diet on CVD.

Whole Fruits and Fruit Fiber Emerging Health Effects

Less than 10% of most Western populations consume adequate levels of whole fruits and dietary fiber with typical intake being about half of the recommended levels. Evidence of the beneficial health effects of consuming adequate levels of whole fruits has been steadily growing, especially regarding their bioactive fiber prebiotic effects and role in improved weight control, wellness and healthy aging. The primary aim of this narrative review article is to examine the increasing number of health benefits which are associated with the adequate intake of whole fruits, especially fruit fiber, throughout the human lifecycle. These potential health benefits include: protecting colonic gastrointestinal health (e.g., constipation, irritable bowel syndrome, inflammatory bowel diseases, and diverticular disease); promoting long-term weight management; reducing risk of cardiovascular disease, type 2 diabetes and metabolic syndrome; defending against colorectal and lung cancers; improving odds of successful aging; reducing the severity of asthma and chronic obstructive pulmonary disease; enhancing psychological well-being and lowering the risk of depression; contributing to higher bone mineral density in children and adults; reducing risk of seborrheic dermatitis; and helping to attenuate autism spectrum disorder severity. Low whole fruit intake represents a potentially more serious global population health threat than previously recognized, especially in light of the emerging research on whole fruit and fruit fiber health benefits.

Agaricus bisporus supplementation reduces high-fat diet-induced body weight gain and fatty liver development

Obesity is a global epidemic characterized not only by excessive fat deposition but also by important complications such as nonalcoholic liver steatosis. Beneficial antiobesogenic effects have been described for some mushrooms. The current study aimed to demonstrate the protective effect of Agaricus bisporus (AB) supplementation against the metabolic alterations induced by high-fat-diet (HFD) feeding. Eight-week-old C57BL/6J mice were fed for 10 weeks with one of the following diets: (1) control diet (n = 7), (2) HFD (n = 7), (3) HFD supplemented with 5% AB (n = 9), and (4) HFD supplemented with 10% AB (n = 9). A pair-fed group was also included for the 10% AB group (n = 6). The impact of AB supplementation on food intake, body weight gain, and liver and fat pad weights was examined. Biochemical, histological, and molecular parameters were also analyzed. Dietary supplementation with 10% AB reduced the HFD-induced increase in body, epididymal, and mesenteric fat weights (p < 0.01, p < 0.05, and p < 0.05, respectively). Supplementation with AB also reduced liver damage in a dose-dependent manner (p < 0.01 and p < 0.001). This effect was confirmed by histological analysis that showed that liver steatosis was markedly reduced in mice fed with AB. The beneficial properties of 10% AB supplementation appear to be mediated through a decrease in food intake and via stimulation of mesenteric and hepatic free-fatty acid beta-oxidation, along with a decrease in epidydimal and hepatic expression of CD36. In conclusion, supplementation with AB prevents excessive body weight gain and liver steatosis induced by HFD consumption.

Dietary fibers, prebiotics, and exopolysaccharides produced by lactic acid bacteria: potential health benefits with special regard to cholesterol-lowering effects

The gastrointestinal (GIT) microbiota, which plays a crucial role in human health, is influenced by a number of factors including diet. Consumption of specific dietary ingredients, such as dietary fibers and prebiotics, is an avenue by which the microbiota can be positively modulated. These substances may also reduce serum cholesterol levels through various mechanisms. Interest has increased in methods of reducing blood cholesterol level, because dyslipidemia is recognized as a contributory risk factor for the development of cardiovascular diseases. Several drugs have been developed for the treatment of hypercholesterolemia; however, undesirable side effects were observed, which have caused concerns about their long-term therapeutic use. Alternatively, many nonpharmacological approaches were tested to reduce elevated serum cholesterol levels. Dietary fibers and prebiotics have particularly beneficial effects on the GIT microbiome, and can also reduce serum cholesterol level through various mechanisms. Lactic acid bacteria (LAB) are potentially capable of synthesizing different polysaccharides, e.g. exopolysaccharides (EPS), which may play a role as prebiotics. LAB-based EPS have the potential to affect the gastrointestinal microbiome and reduce cholesterol. However, as dietary fibers comprise a complex group of substances with remarkably diverse structures, properties, and impacts, EPS also differ greatly and show a multitude of beneficial health effects. This review discusses the current knowledge related to the effects of dietary fibers and prebiotics on the human GIT microbiome, the prebiotic properties of EPS produced by LAB, and the health-promoting benefits of these polymers with special emphasis being given to cholesterol lowering.

Higher Whole-Grain Intake Is Associated with Lower Risk of Type 2 Diabetes among Middle-Aged Men and Women: The Danish Diet, Cancer, and Health Cohort

BACKGROUND

Type 2 diabetes is a major health concern worldwide. Whole grains and cereal fiber may offer protective effects on type 2 diabetes risk. However, few studies have been conducted in cohorts with detailed information on whole-grain cereal intakes and product types and with wide ranges of intake.

Objective

We investigated the associations between whole-grain intake, including intakes of different cereal types and products, and the risk of type 2 diabetes in a population with wide and diverse whole-grain intake.

Methods

We used data from the Danish Diet, Cancer, and Health cohort including 55,465 participants aged 50-65 y at baseline. Of these, 7417 participants were diagnosed with type 2 diabetes during follow-up (median: 15 y). Detailed information on the intake of whole-grain products was available from a food-frequency questionnaire, and total whole-grain intake and whole-grain cereal types (wheat, rye, oats) were calculated in grams per day. Associations were examined by using Cox proportional hazards models with adjustment for potential confounders.

Results

Whole-grain intake was associated with an 11% and 7% lower risk of type 2 diabetes per whole-grain serving (16 g) per day for men and women, respectively [HR (95% CI)-men: 0.89 (0.87, 0.91); women: 0.93 (0.91, 0.96)]. For men, the intake of all whole-grain cereal types investigated (wheat, rye, oats) was significantly associated with a lower risk of type 2 diabetes, but only wheat and oats intake was significantly associated for women. Among the different whole-grain products, rye bread, whole-grain bread, and oatmeal/muesli were significantly associated with a lower risk of type 2 diabetes for both men and women.

Conclusions

In this cohort study, we found consistent associations between high whole-grain intake and lower risk of type 2 diabetes. Overall, an association was found for all different cereals and whole-grain products tested.

Differentiation of Adsorptive and Viscous Effects of Dietary Fibres on Bile Acid Release by Means of In Vitro Digestion and Dialysis

To explain the cholesterol-reducing effects of dietary fibres, one of the major mechanisms proposed is the reduced reabsorption of bile acids in the ileum. The interaction of dietary fibres with bile acids is associated with their viscous or adsorptive effects. Since these fibre characteristics are difficult to investigate in vivo, suitable in vitro methodologies can contribute to understanding the mechanistic principles. We compared the commonly used centrifugal approach with a modified dialysis method using dietary fibre-rich materials from different sources (i.e., barley, citrus, lupin, and potato). Digestion was simulated in vitro with oral, gastric, and small intestinal digestion environments. The chyme was dialysed and released bile acids were analysed by high-performance liquid chromatography. The centrifugation method showed adsorptive effects only for cholestyramine (reference material) and a high-fibre barley product (1.4 µmol taurocholic acid/100 mg dry matter). Alternatively, the dialysis approach showed higher values of bile acid adsorption (2.3 µmol taurocholic acid/100 mg dry matter) for the high-fibre barley product. This indicated an underestimated adsorption when using the centrifugation method. The results also confirmed that the dialysis method can be used to understand the influence of viscosity on bile acid release. This may be due to entrapment of bile acids in the viscous chyme matrix. Further studies on fibre structure and mechanisms responsible for viscous effects are required to understand the formation of entangled networks responsible for the entrapment of the bile acids.

Effects of Quinoa (Chenopodium quinoa Willd.) Consumption on Markers of CVD Risk

A number of epidemiological studies have suggested that diets rich in whole grains are linked to lower cardiovascular disease (CVD) risk and mortality. Quinoa, a pseudo-cereal, is included in the “whole grain” category but the effects of quinoa consumption in humans is not widely studied. Our aim was to undertake a dietary intervention study to investigate the effects of daily consumption of quinoa-enriched bread (providing 20 g quinoa flour) on CVD risk markers compared with a 100% refined wheat bread control. Thirty-seven healthy overweight men (35–70 years, body mass index >25 kg/m²) completed a 4-week cross-over intervention, separated by a 4-week washout period. Fasting blood samples were collected at the beginning and end of each intervention period. Continuous glucose monitoring was undertaken at the end of each intervention period. After 4 weeks of intervention, blood glucose and low density lipoprotein (LDL) cholesterol were significantly lower than baseline in both groups but there was no difference between quinoa and control. Anthropometric measures and other blood metabolites were not different between the two treatments. The cumulative area under the blood glucose curve for the last 4 days of the quinoa intervention tended to be lower than the first 4 days of wash-out (p = 0.054), and was significantly lower than the corresponding period of the wheat treatment (p = 0.039). In conclusion, daily consumption of quinoa in this short-term intervention appears to modify glucose response, but has minimal effects on other CVD risk biomarkers.

Host: Microbiome co-metabolic processing of dietary polyphenols - An acute, single blinded, cross-over study with different doses of apple polyphenols in healthy subjects

Apples are one of the most commonly consumed fruits and their high polyphenol content is considered one of the most important determinants of their health-promoting activities. Here we studied the nutrikinetics of apple polyphenols by UHPLC-HRMS metabolite fingerprinting, comparing bioavailability when consumed in a natural or a polyphenol-enriched cloudy apple juice. Twelve men and women participated in an acute single blind controlled crossover study in which they consumed 250 mL of cloudy apple juice (CAJ), Crispy Pink apple variety, or 250 mL of the same juice enriched with 750 mg of an apple polyphenol extract (PAJ). Plasma and whole blood were collected at time 0, 1, 2, 3 and 5 h. Urine was collected at time 0 and 0-2, 2-5, 5-8, and 8-24 h after juice consumption. Faecal samples were collected from each individual during the study for 16S rRNA gene profiling. As many as 110 metabolites were significantly elevated following intake of polyphenol enriched cloudy apple juice, with large inter-individual variations. The comparison of the average area under the curve of circulating metabolites in plasma and in urine of volunteers consuming either the CAJ or the PAJ demonstrated a stable metabotype, suggesting that an increase in polyphenol concentration in fruit does not limit their bioavailability upon ingestion. Faecal bacteria were correlated with specific microbial catabolites derived from apple polyphenols. Human metabolism of apple polyphenols is a co-metabolic process between human encoded activities and those of our resident microbiota. Here we have identified specific blood and urine metabolic biomarkers of apple polyphenol intake and identified putative associations with specific genera of faecal bacteria, associations which now need confirmation in specifically designed mechanistic studies.

Mediterranean diet and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is emerging as the most common chronic liver disease, and is characterized by a wide spectrum of fat-liver disorders that can result in severe liver disease and cirrhosis. Inflammation and oxidative stress are the major risk factors involved in the pathogenesis of NAFLD. Currently, there is no consensus concerning the pharmacological treatment of NAFLD. However, lifestyle interventions based on exercise and a balanced diet for quality and quantity, are considered the cornerstone of NAFLD management. Mediterranean diet (MD), rich in polyunsaturated fats, polyphenols, vitamins and carotenoids, with their anti-inflammatory and anti-oxidant effects, has been suggested to be effective in preventing cardiovascular risk factors. In adults, MD has also been demonstrated to be efficacious in reducing the risk of metabolic syndrome. However, few studies are available on the effects of the MD in both adult and pediatric subjects with NAFLD. Thus, the aims of the present narrative review are to analyze the current clinical evidence on the impact of MD in patients with NAFLD, and to summarize the main mechanisms of action of MD components on this condition.

A randomized trial of the effects of flaxseed to manage constipation, weight, glycemia, and lipids in constipated patients with type 2 diabetes

Background

To compare the effects of baked flaxseed versus those who received a placebo on constipation symptom scores, weight, glycemic and lipid control in constipated patients with type 2 diabetes (T2D).

Methods

In a single-blinded, randomized controlled trial, 53 constipated patients with T2D with body mass index (BMI) 20.5-48.9 kg/m² received either 10 g of flaxseed pre-mixed in cookies twice per day or placebo cookies for 12 weeks. The constipation symptom scores, BMI, fasting plasma glucose (FPG), glycosylated hemoglobin (HbA1c), and lipid profile were determined at the beginning and end of 4, 8, and 12-week period. Constipation was evaluated with a stool diary (ROME III).

Results

After the 12-week intervention, constipation symptom scores (2.46), weight (- 3.8 kg), BMI (- 1.5 kg/m²), FPG (- 26.7 mg/dl), cholesterol (- 37.3 mg/dl), triglycerides (- 10.4 mg/dl), LDLC (- 21.0 mg/dl), HDLC (4.7 mg/dl), cholesterol/ HDLC ratio (- 1.4 mg/dl) significantly decreased from baseline in the flaxseed group (all P-values < 0.05). The differences of absolute change of constipation symptom scores (2.46 vs. 0.41), weight (- 3.8 vs. 0.0 kg), BMI (- 1.5 vs.-0.1 kg/m²), FPG (- 26.7 vs.-1.9 mg/dl), >HbA1c (- 0.8 vs. 1.0%), cholesterol (- 37.3 vs. -10.4 mg/dl), LDLC (- 21.0 vs. -4.3 mg/dl), and HDLC (4.7 vs. -4.4 mg/dl) between the flaxseed and placebo groups were statistically significant (all P-values < 0.05). The compliance was good and no adverse effects were observed.

Conclusion

In constipated patients with T2D, flaxseed cookies used as a snack may be a useful tool for decreasing constipation symptoms, weight, glycemic and lipid levels.

Trial registration

irct.ir: IRCT20110416006202N2.

Estudio del efecto fisiológico del consumo de arepas enriquecidas con pectina extraída de la cáscara de curuba (Passiflora tripartita var. mollissima)

Se evaluó el efecto fisiológico del consumo de arepas de maíz enriquecidas con 10% (p/p) de pectina extraída de cáscara de curuba sobre los niveles séricos de glucosa y lípidos en adultos voluntarios. La pectina se extrajo con ácido clorhídrico y se precipitó con etanol del 96% (v/v). En primer lugar, los voluntarios consumieron arepa sin pectina por siete días; después, arepa con 10% (p/p) de pectina cítrica comercial por 20 días y, finalmente, arepa con 10% de pectina de curuba por 20 días. Al mismo tiempo, se realizó un análisis sensorial de aceptación. Los resultados mostraron que, al consumir arepa con pectina de curuba, los niveles séricos de glucosa disminuyeron significativamente (5,88% (p = 0,023)), mientras que el perfil lipídico no se afectó. La arepa con pectina de curuba mostró mayor porcentaje de fibra dietética soluble, insoluble y total, así como menor porcentaje de carbohidratos disponibles, respecto a las otras arepas analizadas. El panel sensorial dictaminó baja aceptación en sabor y textura para las arepas con pectina cítrica comercial y con pectina de curuba. Se concluyó que la pectina de curuba puede aprovecharse para la formulación de arepas ya que ofrece a los consumidores un alimento benéfico para reducir los niveles de glucosa en la sangre.

Barley β-glucan improves metabolic condition via short-chain fatty acids produced by gut microbial fermentation in high fat diet fed mice

Dietary intake of barley β-glucan (BG) is known to affect energy metabolism. However, its underlying mechanism remains poorly understood because studies have presented inconsistent results, with both positive and negative effects reported in terms of satiety, energy intake, weight loss, and glycemic control. The objective of this study was to clarify the physiological role underlying the metabolic benefits of barley BG using a mouse model of high fat diet (HFD)-induced obesity. Male 4-wk-old C57BL/6J mice were fed an HFD with 20% barley flour containing either high BG (HBG; 2% BG) or low BG (LBG; 0.6% BG) levels under conventional and germ-free (GF) conditions for 12 wks. In addition, mice were fed either an HFD with 5% cellulose (HFC; high fiber cellulose) or 5% barley BG (HFB; high fiber β-glucan) for 12 wks. Then, metabolic parameters, gut microbial compositions, and the production of fecal short-chain fatty acids (SCFAs) were analyzed. The weight gain and fat mass of HBG-fed mice were lower than those of control mice at 16-wk-old. Moreover, the secretion of the gut hormones PYY and GLP-1 increased in HBG-fed mice, thereby reducing food intake and improving insulin sensitivity by changing the gut microbiota and increasing SCFAs (especially, butyrate) under conventional condition. These effects in HBG-fed mice were abolished under GF conditions. Moreover, the HFB diets also increased PYY and GLP-1 secretion, and decreased food intake compared with that in HFC-fed mice. These results suggest that the beneficial metabolic effects of barley BG are primary due to the suppression of appetite and improvement of insulin sensitivity, which are induced by gut hormone secretion promoted via gut microbiota-produced SCFAs.

Pectin and Pectin-Based Composite Materials: Beyond Food Texture

Pectins are plant cell wall natural heteropolysaccharides composed mainly of α-1-4 d-galacturonic acid units, which may or may not be methyl esterified, possesses neutral sugars branching that harbor functional moieties. Physicochemical features as pH, temperature, ions concentration, and cosolute presence, affect directly the extraction yield and gelling capacity of pectins. The chemical and structural features of this polysaccharide enables its interaction with a wide range of molecules, a property that scientists profit from to form new composite matrices for target/controlled delivery of therapeutic molecules, genes or cells. Considered a prebiotic dietary fiber, pectins meetmany regulations easily, regarding health applications within the pharmaceutical industry as a raw material and as an agent for the prevention of cancer. Thus, this review lists many emergent pectin-based composite materials which will probably palliate the impact of obesity, diabetes and heart disease, aid to forestall actual epidemics, expand the ken of food additives and food products design.

The cholesterol-lowering effect of statins is potentiated by whole grains intake. The Polish Norwegian Study (PONS)

BACKGROUND

Hypercholesterolemia treatment guidelines emphasize an adequate whole grains (WG) intake, alone or complementary to pharmacological treatment. We conducted this study to compare the prevalence of adequate WG intake and levels of blood lipids according to the statin/WG intake status.

METHODS

This cross-sectional analysis of a community-based study included 12,754 men and women, age 45-64. Statin use over past 30days was recorded by trained nurses. Food intake over past 12months was assessed by a validated food-frequency questionnaire. Adequate WG intake was defined as ≥3oz-equivalents/day, representing ≥3WGservings/day.

RESULTS

The prevalence of an adequate WG intake was marginally superior in statin users (26.79%) than non-users (21.51%). This superiority was attenuated after multiple covariates adjustment (PR 1.12, 95%CI 1.02-1.22). Statin users with an adequate WG intake had lower multivariable-adjusted mean blood total cholesterol (185.14mg/dL vs. 190.14mg/dL) and LDL cholesterol (103.30mg/dL vs. 108.19mg/dL) than those with an inadequate WG intake. Statin users with an adequate WG intake had lower odds (OR, 95% CI) of having TC≥240mg/dL (OR 0.67, 95% CI 0.46-0.98) and lower odds of having LDL≥100mg/dL (OR 0.72, 95% CI 0.58-0.89), compared to statin users with inadequate WG intake. A subgroup analysis restricted to those with prevalent CVD yielded similar results.

CONCLUSIONS

In this community based sample of middle-aged adults, only one in four statin users had adequate whole grain intake. Statin users with adequate WG intake had statistically and clinically significant lower levels of blood total- and LDL-cholesterol.

Modification of carrot (Daucus carota Linn. var. Sativa Hoffm.) pomace insoluble dietary fiber with complex enzyme method, ultrafine comminution, and high hydrostatic pressure

Insoluble dietary fiber (DF) extracted from carrot pomace was modified by complex enzyme method, ultrafine comminution and high hydrostatic pressure and their structural, physicochemical, and functional properties were evaluated. Results showed that complex enzyme method increased the content of soluble DF to 15.07%, and the cholesterol adsorption capacity peaked; ultrafine comminution greatly improved the total antioxidant activities, DPPH radical scavenging capacity and antioxidant abilities in linoleic acid system of DF; high hydrostatic pressure led to a significant increase in capacities of water retention (7.14 g/g, 600 MPa), water swelling (10.02 mL/g, 500 MPa), oil retention (2.35 g/g, 500 MPa), cation exchange (2.29 mmol/g, 600 MPa), and glucose adsorption (2.634 mmol/g, 400 MPa). Furthermore, SEM showed that surface structures of all modified DF were loose. Overall, three kinds of modification methods have shown their respective advantages. Modified DF from carrot pomace can be applied as a functional ingredient in diverse food products.

Health Benefits of the Mediterranean Diet: Metabolic and Molecular Mechanisms

Consuming a Mediterranean diet rich in minimally processed plant foods has been associated with a reduced risk of developing multiple chronic diseases and increased life expectancy. Data from several randomized clinic trials have demonstrated a beneficial effect in the primary and secondary prevention of cardiovascular disease, type 2 diabetes, atrial fibrillation, and breast cancer. The exact mechanism by which an increased adherence to the traditional Mediterranean diet exerts its favorable effects is not known. However, accumulating evidence indicates that the five most important adaptations induced by the Mediterranean dietary pattern are: (a) lipid-lowering effect, (b) protection against oxidative stress, inflammation and platelet aggregation, (c) modification of hormones and growth factors involved in the pathogenesis of cancer, (d) inhibition of nutrient sensing pathways by specific amino acid restriction, and (e) gut microbiota-mediated production of metabolites influencing metabolic health. More studies are needed to understand how single modifications of nutrients typical of the Mediterranean diet interact with energy intake, energy expenditure, and the microbiome in modulating the key mechanisms that promote cellular, tissue, and organ health during aging.

Enhanced anti-obesity effects of bacterial cellulose combined with konjac glucomannan in high-fat diet-fed C57BL/6J mice

This study aimed to investigate the effects of supplementation with bacterial cellulose (BC), konjac glucomannan (KGM) and combined BC/KGM fiber on high-fat (HF)-diet-induced obesity in C57BL/6J mice.

Regulation of low-density lipoprotein cholesterol by intestinal inflammation and the acute phase response

Systemic inflammation, induced by disease or experimental intervention, is well established to result in elevated levels of circulating triglycerides, and reduced levels of high-density lipoprotein-cholesterol (HDL-C), in most mammalian species. However, the relationship between inflammation and low-density lipoprotein-cholesterol (LDL-C) concentrations is less clear. Most reports indicate that systemic inflammation, as observed during sepsis or following high dose experimental endotoxaemia, lowers total, and LDL-C in man. However, isolated reports have suggested that certain inflammatory conditions are associated with increased LDL-C. In this review, we summarize the emerging evidence that low-grade inflammation specifically of intestinal origin may be associated with increased serum LDL-C levels. Preliminary insights into potential mechanisms that may mediate these effects, including those connecting inflammation to trans-intestinal cholesterol efflux (TICE), are considered. We conclude that this evidence supports the potential downregulation of major mediators of TICE by inflammatory mediators in vitro and during intestinal inflammation in vivo. The TICE-inflammation axis therefore merits further study in terms of its potential to regulate serum LDL-C, and as a readily druggable target for hypercholesterolaemia.

The impact of oat structure and β-glucan on in vitro lipid digestion

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The structure of oat tissue is an important factor for determining its influence on (in vitro) lipid digestion.

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β-glucan release from oat cell walls during digestion was not complete.

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Processing of oats affects the rate and extent of lipolysis.

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Viscosity is not the only factor affecting lipolysis.

Oat β-glucan has been shown to play a positive role in influencing lipid and cholesterol metabolism. However, the mechanisms behind these beneficial effects are not fully understood.

The purpose of the current work was to investigate some of the possible mechanisms behind the cholesterol lowering effect of oat β-glucan, and how processing of oat modulates lipolysis. β-Glucan release, and the rate and extent of lipolysis measured in the presence of different sources of oat β-glucan, were investigated during gastrointestinal digestion.

Only a fraction of the original β-glucan content was released during digestion. Oat flakes and flour appeared to have a more significant effect on lipolysis than purified β-glucan.

These findings show that the positive action of β-glucan is likely to involve complex processes and interactions with the food matrix. This work also highlights the importance of considering the structure and physicochemical properties of foods, and not just the nutrient content.

Myocardial metabolic alterations in mice with diet-induced atherosclerosis: linking sulfur amino acid and lipid metabolism

Atherosclerosis is a leading cause of cardiovascular disease (CVD), but the effect of diet on the atherosclerotic heart’s metabolism is unclear. We used an integrated metabolomics and lipidomics approach to evaluate metabolic perturbations in heart and serum from mice fed an atherogenic diet (AD) for 8, 16, and 25 weeks. Nuclear magnetic resonance (NMR)-based metabolomics revealed significant changes in sulfur amino acid (SAA) and lipid metabolism in heart from AD mice compared with heart from normal diet mice. Higher SAA levels in AD mice were quantitatively verified using liquid chromatography-mass spectrometry (LC/MS). Lipidomic profiling revealed that fatty acid and triglyceride (TG) levels in the AD group were altered depending on the degree of unsaturation. Additionally, levels of SCD1, SREBP-1, and PPARγ were reduced in AD mice after 25 weeks, while levels of reactive oxygen species were elevated. The results suggest that a long-term AD leads to SAA metabolism dysregulation and increased oxidative stress in the heart, causing SCD1 activity suppression and accumulation of toxic TGs with a low degree of unsaturation. These findings demonstrate that the SAA metabolic pathway is a promising therapeutic target for CVD treatment and that metabolomics can be used to investigate the metabolic signature of atherosclerosis.

The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta-analysis of 45 randomized placebo-controlled trials

Flaxseed consumption may be inversely associated with obesity; however, findings of available randomized controlled trials (RCTs) are conflicting. The present study aimed to systematically review and analyse RCTs assessing the effects of flaxseed consumption on body weight and body composition. PubMed, Medline via Ovid, SCOPUS, EMBASE and ISI Web of Sciences databases were searched up to November 2016. Mean changes in body composition indices including body weight, body mass index (BMI) and waist circumference were extracted. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). Heterogeneity between studies was assessed with the I² test. Publication bias and subgroup analyses were also performed. The quality of articles was assessed via the Jadad scale. A total of 45 RCTs were included. Meta-analyses suggested a significant reduction in body weight (WMD: -0.99 kg, 95% CI: -1.67, -0.31, p = 0.004), BMI (WMD: -0.30 kg m^-2 , 95% CI: -0.53, -0.08, p = 0.008) and waist circumference (WMD: -0.80 cm, 95% CI: -1.40, -0.20, p = 0.008) following flaxseed supplementation. Subgroup analyses showed that using whole flaxseed in doses ≥30 g d^-1 , longer-term interventions (≥12 weeks) and studies including participants with higher BMI (≥ 27 kg m^-2 ) had positive effects on body composition. Whole flaxseed is a good choice for weight management particularly for weight reduction in overweight and obese participants.

Lipid Lowering with Soluble Dietary Fiber

Consumption of dietary soluble fibers has been associated with health benefits such as reduced lipid levels, lower blood pressure, improved blood glucose control, weight loss, improved immune function, and reduced inflammation. Many of these health benefits relate to a reduced risk of developing cardiovascular disease. In this paper, we have reviewed recent studies on the hypocholesterolemic effects of dietary soluble fibers as well as fiber-rich foods. Findings include the following: (a) consumption of water-soluble, viscous-forming fibers can reduce total and low-density lipoprotein cholesterol levels by about 5-10 %; (b) minimal changes of high-density lipoprotein cholesterol or triglyceride levels were observed; (c) cholesterol-lowering properties of soluble fibers depend on their physical and chemical properties; and (d) medium to high molecular weight fibers are more effective in reducing lipid levels. Hypocholesterolemic benefits were also observed with some fiber-rich foods, such as whole oats, whole barley, legumes, peas, beans, flax seeds, apples, and citrus foods.

Effects of concentrated and dephytinized wheat bran and rice bran addition on bread properties

Wheat bran and rice bran were concentrated in terms of dietary fiber and were dephytinized by two different methods (fermentation and hydrothermal). Untreated, concentrated, concentrated-dephytinized by fermentation method, and concentrated-dephytinized by hydrothermal method bran samples were each incorporated into flour at levels of 0, 10, 15, and 20%, and their effects on bread properties were investigated. Unprocessed wheat bran and rice bran addition decreased the volume yield, and the specific volume of the bread depends on the incorporation level. A further decrease was observed with the addition of concentrated bran. However, the dephytinization treatments slightly improved these values. The same pattern was observed for the total number of cells and the total cell area of bread crumbs. Both wheat bran and rice bran were observed to cause a darker crumb color, and the effects of bran samples on crumb color were more pronounced after the dephytinization treatment. The addition of concentrated wheat bran and rice bran significantly increased hardness, as well as decreasing springiness, cohesiveness, and resilience of the bread, depending on the bran levels. Although dephytinization treatments enhanced the textural properties of bread, these results were still inferior to those obtained using bread produced with untreated bran. Regarding the dephytinization treatments, the influence of fermentation treatment on bread properties was slightly beneficial compared to hydrothermal treatment.

PRACTICAL APPLICATIONS

Consumption of dietary fiber offers a range of health benefits. Cereal bran has great potential as a dietary fiber source. However, this bran's high phytic acid content and adverse effects on bread quality limit that potential. It is possible to obtain high dietary fiber and low phytic acid bran samples through bran concentration and dephytinization treatments. The dephytinization treatment is an effective method for degradation of phytic acid. The negative effects of wheat bran and rice bran on bread quality decreased significantly following the dephytinization treatments. This study demonstrated that fiber-enriched bread with low phytic acid content and acceptable texture can be produced using concentrated and dephytinized bran.

Emerging concepts in the nutraceutical and functional properties of pectin-A Review

Pectin is a structural heteropolysaccharide found ubiquitously in terrestrial plants. It finds diverse food applications such as that of a gelling agent, stabilizer, and fat replacer. In the pharmaceutical arena, pectin exhibits a number of functions, from decreasing blood fat to combating various types of cancers. This review shows the shift of pectin from its conventional roles to its progressive applications. Insights into the advances in the production of pectin, the role it plays as a nutraceutical, possible prebiotic potential and a delivery vehicle for probiotics, and food applications are highlighted. Bioactive and functional properties of pectin are discussed and how the structural built up defines them, is emphasized. As a biopolymer, the applications of pectin in active packaging are also mentioned.

Role of polysaccharides in food, digestion, and health

Polysaccharides derived from plant foods are major components of the human diet, with limited contributions of related components from fungal and algal sources. In particular, starch and other storage carbohydrates are the major sources of energy in all diets, while cell wall polysaccharides are the major components of dietary fiber. We review the role of these components in the human diet, including their structure and distribution, their modification during food processing and effects on functional properties, their behavior in the gastrointestinal tract, and their contribution to healthy diets.

Application and Development Prospects of Dietary Fibers in Flour Products

Dietary fibers are often characterized by high nutritional quality, as they are able to cure many chronic diseases and improve texture, sensory characteristics, and shelf life of foods. Here, the following aspects of dietary fibers have been reviewed: nutritional properties, including the ability to regulate blood sugar levels, effects on microorganisms, antioxidant effect, potential role in losing weight, ability to regulate blood lipids, application in flour products such as bread and Chinese noodles, challenges such as dark color, rough texture, and poor solubility, and potential solutions that include modification methods. The primary purpose of this review is to comprehensively evaluate potential applications of dietary fibers in flour products, addressing common problems and reviewing potential solutions to promote further study and applications of dietary fibers.

Sigumjang (fermented barley bran) water-soluble extracts inhibit the expression of adipogenic and lipogenic regulators in 3T3-L1 adipocytes

Sigumjang prepared from fermented barley bran is a traditional fermented food found only in the Gyeongsang-do area of South Korea. There have been no studies reported to date despite the potential bioactivities of sigumjang. In this study, the anti-obesity activities of sigumjang extracts (SEs) during 3T3-L1 differentiation into adipocytes were investigated. SEs inhibited adipocyte differentiation by suppressing the CCAAT/enhancer binding protein-β and sterol regulatory element binding protein-1c expression in the early stage of differentiation, followed by the suppression of the peroxisome proliferator-activated receptor-γ, CCAAT/enhancer binding protein-α, and adiponectin. These changes in adipogenic markers induced inhibition of lipogenesis via down-regulation of mainly fatty acid synthase, acetyl-CoA carboxylase, fatty acid binding protein 4, and perilipin. These results were more significant in the extract of sigumjang fermented with isolated Bacillus amyloliquefaciens MFST compared to naturally fermented sigumjang group. SEs can be considered as a useful material for developing food with health benefits and anti-obesity properties.

The physicochemical properties, in vitro binding capacities and in vivo hypocholesterolemic activity of soluble dietary fiber extracted from soy hulls

Soluble dietary fibers (SDFs) have earned a healthy reputation due to their distinguished physiological functions. In this study, SDF was efficiently extracted from soy hulls using a phosphate-assisted subcritical water extraction method. The physicochemical properties, in vitro binding capacities and in vivo hypocholesterolemic activity of soy hull soluble dietary fiber (SHSDF) were evaluated. The results indicated that the major component of SHSDF was pectic polysaccharides, and with comparison to commercial oat β-glucan, SHSDF had favorable solubility, viscosity, water-holding ability (5.26 g water per g sample), and oil holding capacity (4.83 g oil per g sample). It also possessed good in vitro cholesterol-binding capacity (6.18 mg g-1 sample at pH 2 and 7.62 mg g-1 sample at pH 7), bile acid-binding capacity (3.3, 1.73 and 6.65 μM of GCA, GCDCA and GDCA per 100 mg of sample), glucose dialysis retardation index (64.76%), and in vivo hypocholesterolemic activity (16.88% and 35.28% reduction in serum total cholesterol and LDL level in rats, respectively). These data suggest that SHSDF has great potential in food applications, especially in the development of functional food ingredients.

Nutritional management of hyperapoB

Plasma apoB is a more accurate marker of the risk of CVD and type 2 diabetes (T2D) than LDL-cholesterol; however, nutritional reviews targeting apoB are scarce. Here we reviewed eighty-seven nutritional studies and present conclusions in order of strength of evidence. Plasma apoB was reduced in all studies that induced weight loss of 6–12 % using hypoenergetic diets (seven studies; 5440–7110 kJ/d; 1300–1700 kcal/d; 34–50 % carbohydrates; 27–39 % fat; 18–24 % protein). When macronutrients were compared in isoenergetic diets (eleven studies including eight randomised controlled trials (RCT); n 1189), the diets that reduced plasma apoB were composed of 26–51 % carbohydrates, 26–46 % fat, 11–32 % protein, 10–27 % MUFA, 5–14 % PUFA and 7–13 % SFA. Replacement of carbohydrate by MUFA, not SFA, decreased plasma apoB. Moreover, dietary enriching with n-3 fatty acids (FA) (from fish: 1·1–1·7 g/d or supplementation: 3·2–3·4 g/d EPA/DHA or 4 g/d EPA), psyllium (about 8–20 g/d), phytosterols (about 2–4 g/d) or nuts (30–75 g/d) also decreased plasma apoB, mostly in hyperlipidaemic subjects. While high intake of trans-FA (4·3–9·1 %) increased plasma apoB, it is unlikely that these amounts represent usual consumption. Inconsistent data existed on the effect of soya proteins (25–30 g/d), while the positive association of alcohol consumption with low plasma apoB was reported in cross-sectional studies only. Five isoenergetic studies using Mediterranean diets (including two RCT; 823 subjects) reported a decrease of plasma apoB, while weaker evidence existed for Dietary Approaches to Stop Hypertension (DASH), vegetarian, Nordic and Palaeolithic diets. We recommend using a Mediterranean dietary pattern, which also encompasses the dietary components reported to reduce plasma apoB, to target hyperapoB and reduce the risks of CVD and T2D.

Re-evaluation of the mechanisms of dietary fibre and implications for macronutrient bioaccessibility, digestion and postprandial metabolism

The positive effects of dietary fibre on health are now widely recognised; however, our understanding of the mechanisms involved in producing such benefits remains unclear. There are even uncertainties about how dietary fibre in plant foods should be defined and analysed. This review attempts to clarify the confusion regarding the mechanisms of action of dietary fibre and deals with current knowledge on the wide variety of dietary fibre materials, comprising mainly of NSP that are not digested by enzymes of the gastrointestinal (GI) tract. These non-digestible materials range from intact cell walls of plant tissues to individual polysaccharide solutions often used in mechanistic studies. We discuss how the structure and properties of fibre are affected during food processing and how this can impact on nutrient digestibility. Dietary fibre can have multiple effects on GI function, including GI transit time and increased digesta viscosity, thereby affecting flow and mixing behaviour. Moreover, cell wall encapsulation influences macronutrient digestibility through limited access to digestive enzymes and/or substrate and product release. Moreover, encapsulation of starch can limit the extent of gelatinisation during hydrothermal processing of plant foods. Emphasis is placed on the effects of diverse forms of fibre on rates and extents of starch and lipid digestion, and how it is important that a better understanding of such interactions with respect to the physiology and biochemistry of digestion is needed. In conclusion, we point to areas of further investigation that are expected to contribute to realisation of the full potential of dietary fibre on health and well-being of humans.

Hypocholesterolemic Properties and Prebiotic Effects of Mexican Ganoderma lucidum in C57BL/6 Mice

Edible and medicinal mushrooms contain bioactive compounds with promising effects on several cardiovascular risk biomarkers. However, strains of Ganoderma lucidum of Mexican origin have not yet been studied. Standardized extracts of G. lucidum (Gl) were given to C57BL/6 mice fed a high-cholesterol diet compared with the drug simvastatin. The effects of the extracts on serum biochemical parameters, liver lipid content, cholesterol metabolism, and the composition of gut microbiota were assessed. Acetylsalicylic acid (10 mM) added to the cultivation substrate modulated properties of Gl extracts obtained from mature basidiomata. Compared to the high-cholesterol diet group, the consumption of Gl extracts significantly reduced total serum cholesterol (by 19.2% to 27.1%), LDL-C (by 4.5% to 35.1%), triglyceride concentration (by 16.3% to 46.6%), hepatic cholesterol (by 28.7% to 52%) and hepatic triglycerides (by 43.8% to 56.6%). These effects were associated with a significant reduction in the expression of lipogenic genes (Hmgcr, Srebp1c, Fasn, and Acaca) and genes involved in reverse cholesterol transport (Abcg5 and Abcg8), as well as an increase in Ldlr gene expression in the liver. No significant changes were observed in the gene expression of Srebp2, Abca1 or Cyp7a1. In several cases, Gl-1 or Gl-2 extracts showed better effects on lipid metabolism than the drug simvastatin. A proposed mechanism of action for the reduction in cholesterol levels is mediated by α-glucans and β-glucans from Gl, which promoted decreased absorption of cholesterol in the gut, as well as greater excretion of fecal bile acids and cholesterol. The prebiotic effects of Gl-1 and Gl-2 extracts modulated the composition of gut microbiota and produced an increase in the Lactobacillaceae family and Lactobacillus genus level compared to the control group, high-cholesterol diet group and group supplemented with simvastatin. Mexican genetic resources of Gl represent a new source of bioactive compounds showing hypocholesterolemic properties and prebiotic effects.

Hypocholesterolemic effect of quercetin-rich onion peel extract in C57BL/6J mice fed with high cholesterol diet

Onion peel (OP) extract is known as a rich source of flavonoids, mainly quercetin. We hypothesized that OP has hypocholesterolemic effects. To investigate the effect of OP, C57BL/6J mice were divided into 4 dietary groups (n=10); normal diet (ND); high cholesterol diet (HC); and high cholesterol diet with 100 or 200 mg OP extract (OP-100 or OP-200, respectively) per kg of body weight. After 12 weeks, lower values of liver weight, serum total cholesterol levels, LDL cholesterol, atherogenic index, cardiac risk factor, hepatic triacylglycerol, and total cholesterol, and higher fecal cholesterol levels were observed in the OP-200 than in the HC group. The hepatic mRNA expression levels of low-density lipoprotein receptors (LDL-R) and cholesterol 7-alpha-monooxygenase (CYP7A1) were high in the OP-200 compared to the HC group. These observations suggest that OP promoted lowering of serum and hepatic cholesterol in mice primarily via fecal excretion.

Use of metabolomics and lipidomics to evaluate the hypocholestreolemic effect of Proanthocyanidins from grape seed in a pig model

SCOPE

This work aims to evaluate changes in the fecal metabolomic profile due to grape seed extract (GSE) intake by untargeted and targeted analysis using high resolution mass spectrometry in conjunction with multivariate statistics.

METHODS AND RESULTS

An intervention study with six crossbred female pigs was performed. The pigs followed a standard diet for 3 days, then they were fed with a supplemented diet containing 1% (w/w) of MegaNatural® Gold grape seed extract for 6 days. Fresh pig fecal samples were collected daily. A combination of untargeted high resolution mass spectrometry, multivariate analysis (PLS-DA), data-dependent MS/MS scan, and accurate mass database matching was used to measure the effect of the treatment on fecal composition. The resultant PLS-DA models showed a good discrimination among classes with great robustness and predictability. A total of 14 metabolites related to the GSE consumption were identified including biliary acid, dicarboxylic fatty acid, cholesterol metabolites, purine metabolites, and eicosanoid metabolites among others. Moreover, targeted metabolomics using GC-MS showed that cholesterol and its metabolites fecal excretion was increased due to the proanthocyanidins from grape seed extract.

CONCLUSION

The results show that oligomeric procyanidins from GSE modifies bile acid and steroid excretion, which could exert a hypocholesterolemic effect.