Bioactivity of oats as it relates to cardiovascular disease

Relationship between Oat Consumption, Gut Microbiota Modulation, and Short-Chain Fatty Acid Synthesis: An Integrative Review

The gut microbiota consists of a set of microorganisms that colonizes the intestine and ferment fibers, among other nutrients, from the host's diet. A healthy gut microbiota, colonized mainly by beneficial microorganisms, has a positive effect on digestion and plays a role in disease prevention. However, dysregulation of the gut microbiota can contribute to various diseases. The nutrition of the host plays an important role in determining the composition of the gut microbiota. A healthy diet, rich in fiber, can beneficially modulate the gut microbiota. In this sense, oats are a source of both soluble and insoluble fiber. Oats are considered a functional ingredient with prebiotic potential and contain plant proteins, unsaturated fats, and antioxidant compounds. The impact of oat consumption on the gut microbiota is still emerging. Associations between oat consumption and the abundance of Akkermansia muciniphila, Roseburia, Lactobacillus, Bifidobacterium, and Faecalibacterium prausnitzii have already been observed. Therefore, this integrative review summarizes the findings from studies on the relationship between oat consumption, the gut microbiota, and the metabolites, mainly short-chain fatty acids, it produces.

Nutritional and Phytochemical Composition and Associated Health Benefits of Oat (Avena sativa) Grains and Oat-Based Fermented Food Products

Oats (Avena sativa L.) are a popular functional cereal grain due to their numerous health benefits. This review article summarized the information on the chemical composition and phytonutrients of oats grown in different countries. It also reviewed recently developed fermented oat products to highlight their potential for human health. Oats have an interesting nutritional profile that includes high-quality protein, unsaturated fats, soluble fiber, polyphenolic compounds, and micronutrients. Oat grain has a unique protein composition, with globulins serving as the primary storage protein, in contrast to other cereals, where prolamins are the main storage proteins. Oats have the highest fat content of any cereal, with low saturated fatty acids and high essential unsaturated fatty acid content, which can help reduce the risk of cardiovascular diseases. Oats are a good source of soluble dietary fiber, particularly β-glucan, which has outstanding functional properties and is extremely important in human nutrition. β-Glucan has been shown to lower blood cholesterol and glucose absorption in the intestine, thereby preventing diseases such as cardiovascular injury, dyslipidemia, hypertension, inflammatory state, and type 2 diabetes. Oats also contain high concentration of antioxidant compounds. Avenanthramides, which are unique to oats, are powerful antioxidants with high antioxidative activity in humans. Recognizing the nutritional benefits of oats, oat-based fermented food products are gaining popularity as functional foods with high probiotic potential.

Determination of Polar Lipids in Wheat and Oat by a Complementary Approach of Hydrophilic Interaction Liquid Chromatography and Reversed-Phase High-Performance Liquid Chromatography Hyphenated with High-Resolution Mass Spectrometry

Cereals contain lipids that fulfill important physiological roles and are associated with stress in the plant. However, many of the specific biological roles of lipids are yet unknown. Comprehensive analysis of these polar lipid categories in whole grain wheat and oat, cereals highly relevant also in nutrition, was performed. Hydrophilic interaction liquid chromatography (HILIC) and reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with high-resolution mass spectrometry using electrospray ionization in both positive and negative ionization mode was used. Exploiting the different separation mechanisms, HILIC was used as a screening method for straightforward lipid class assignment and enabled differentiation of isomeric lipid classes, like phosphatidylethanolamine and lyso-N-acylphosphatidylethanolamine, while RP-HPLC facilitated separation of constitutional isomers. In combination with data-dependent MS/MS experiments, 67 lipid species belonging to nine polar lipid classes could be identified. Furthermore, with both ionization modes, fatty acyl chains directly connected to the lipid headgroups could be assigned. This work focused on the four lipid classes N-acylphosphatidylethanolamines, acyl-monogalactosyldiacylglycerols, digalactosyldiacylglycerols, and monogalactosyldiacylglycerols as they were less studied in detail in the past. Applying the complementary approach, the relative lipid species compositions in these lipid classes was investigated in detail.

Oat AsDA1-2D enhances heat stress tolerance and negatively regulates seed-storage globulin

The importance of oats has increased because of their high nutritional value and health benefits in the human diet. High-temperature stress during the reproductive growth period has a detrimental effect on grain morphology by changing the structure and concentration of several seed-storage proteins. DA1, a conserved ubiquitin-proteasome pathway component, plays an important role in regulating grain size by controlling cell proliferation in maternal integuments during the grain-filling stage. However, there have been no reports or studies on oat DA1 genes. In this study, we identified three DA1-like genes (AsDA1-2D, AsDA1-5A, and AsDA1-1D) using genome-wide analysis. Among these, AsDA1-2D was found to be responsible for high-temperature stress tolerance via a yeast thermotolerance assay. The physical interaction of AsDA1-2D with oat-storage-globulin (AsGL-4D) and a protease inhibitor (AsPI-4D) was observed using yeast two-hybrid screening. A subcellular localization assay revealed that AsDA1-2D and its interacting proteins are localized in the cytosol and plasma membrane. An in vitro pull-down assay showed that AsDA1-2D forms a complex with both AsPI-4D and AsGL-4D. An in vitro cell-free degradation assay showed that AsGL-4D was degraded by AsDA1-2D under high-temperature conditions and that AsPI-4D inhibited the function of AsDA1-2D. These results suggest that AsDA1-2D acts as a cysteine protease and negatively regulates oat-grain-storage-globulin under heat stress.

Polyploidization Increases the Lipid Content and Improves the Nutritional Quality of Rice

Plant polyploidization is frequently associated with changes in nutrient contents. However, the possible contribution of metabolites to this change has not been investigated by characterizing the metabolite contents of diploid and tetraploid forms of rice (Oryza sativa L.). We compared the metabolites of a group of diploid-tetraploid japonica brown rice and a group of diploid-tetraploid indica brown rice based on liquid chromatography-tandem mass spectrometry. In total, 401 metabolites were identified; of these, between the two diploid-tetraploid groups, 180 showed opposite expression trends, but 221 showed the same trends (147 higher abundance vs. 74 lower abundance). Hierarchical cluster analysis of differential metabolites between diploid and tetraploid species showed a clear grouping pattern, in which the expression abundance of lipids, amino acids and derivatives, and phenolic acids increased in tetraploids. Further analysis revealed that the lipids in tetraploid rice increased significantly, especially unsaturated fatty acids and phospholipids. This study provides further basis for understanding the changes in rice nutritional quality following polyploidization and may serve as a new theoretical reference for breeding eutrophic or functional rice varieties via polyploidization.

The Prebiotic Effects of Oats on Blood Lipids, Gut Microbiota, and Short-Chain Fatty Acids in Mildly Hypercholesterolemic Subjects Compared With Rice: A Randomized, Controlled Trial

Phytochemicals derived from oats are reported to possess a beneficial effect on modulating dyslipidemia, specifically on lowering total and LDL cholesterol. However, deeper insights into its mechanism remain unclear. In this randomized controlled study, we assigned 210 mildly hypercholesterolemic subjects from three study centers across China (Beijing, Nanjing, and Shanghai) to consume 80 g of oats or rice daily for 45 days. Plasma lipid profiles, short chain fatty acids (SCFAs), and fecal microbiota were measured. The results showed that total cholesterol (TC) and non-high-density lipoprotein cholesterol (non-HDL-C) decreased significantly with both oats and rice intake after 30 and 45 days. The reduction in TC and non-HDL-C was greater in the participants consuming oats compared with rice at day 45 (p = 0.011 and 0.049, respectively). Oat consumption significantly increased the abundance of Akkermansia muciniphila and Roseburia, and the relative abundance of Dialister, Butyrivibrio, and Paraprevotella, and decreased unclassified f-Sutterellaceae. In the oat group, Bifidobacterium abundance was negatively correlated with LDL-C (p = 0.01, r = −0.31) and, TC and LDL-C were negatively correlated to Faecalibacterium prausnitzii (p = 0.02, r = −0.29; p = 0.03, r = −0.27, respectively). Enterobacteriaceae, Roseburia, and Faecalibacterium prausnitzii were positively correlated with plasma butyric acid and valeric acid concentrations and negatively correlated to isobutyric acid. HDL-C was negatively correlated with valeric acid (p = 0.02, r = −0.25) and total triglyceride (TG) was positively correlated to isovaleric acid (p = 0.03, r = 0.23). Taken together, oats consumption significantly reduced TC and LDL-C, and also mediated a prebiotic effect on gut microbiome. Akkermansia muciniphila, Roseburia, Bifidobacterium, and Faecalibacterium prausnitzii, and plasma SCFA correlated with oat-induced changes in plasma lipids, suggesting prebiotic activity of oats to modulate gut microbiome could contribute towards its cholesterol-lowering effect.

An overview on interactions between natural product-derived β-glucan and small-molecule compounds

β-Glucans are widely found in plants and microorganisms, which has a variety of functional activities. During production and application, interactions with other components have a great influence on the structure and functional properties of β-glucan. In this paper, interactions (including non-covalent interaction and free-radical reaction) between natural product derived β-glucan and ascorbic acid, polyphenols, bile acids/salts, metal ion or other compounds were summarized. Besides, the mechanism and influence factors of interactions between β-glucan and small-molecule compounds, and their effects on the functional properties of β-glucan were detailed. This review aims to develop an understanding and practical suggestions on interactions between β-glucan and small-molecule compounds, which is expected to provide a useful reference for processing and application.

Natural products for controlling hyperlipidemia: review

Hyperlipidemia is an abnormality of lipid metabolism, characterized by an elevation of total cholesterol, triglyceride, and low density lipoprotein-cholesterol, and/or a decreasing of high density lipoprotein cholesterol in circulating levels. Hyperlipidemia has been ranked as one of the greatest risk factors contributing to prevalence and severity of coronary heart diseases. Hyperlipidemia-associated lipid disorders are considered the cause of atherosclerotic cardiovascular disease. There has been a growing interest in natural products and their role in the maintenance and improvement of health and wellness. The cholesterol-lowering effect of dietary plants has been well studied and various natural products were shown to be helpful in lowering plasma cholesterol levels and encouraging safety profile. The main focus of this review is to describe what we know to date of natural products, along with their lipid-lowering mechanisms, which are either through inhibition of cholesterol absorption, inhibition of cholesterol synthesis or antioxidant mechanisms.

Oatmeal-Containing Breakfast is Associated with Better Diet Quality and Higher Intake of Key Food Groups and Nutrients Compared to Other Breakfasts in Children

Oatmeal is a whole grain (WG) food rich in fiber and other nutrients. The study objective was to compare diet quality and nutrient intake of children consuming oatmeal breakfasts to those of children consuming other breakfasts using the National Health and Nutrition Examination Survey (NHANES) 2011–2014. Dietary intake data from 5876 children aged 2–18 years were divided by breakfast food consumption: oatmeal breakfasts, “Doughnuts, sweet rolls, pastries”, “Pancakes, waffles, French toast”, “Eggs and omelets”, “Ready-to-eat cereal, lower sugar”, and “Ready-to-eat cereal, higher sugar” were used to assess diet quality and intake of food groups and nutrients using the USDA Healthy Eating Index-2015 (HEI-2015), Food Patterns Equivalents Database, and Food and Nutrient Database for Dietary Studies, respectively. As compared to consumers of other breakfasts or breakfast skippers, oatmeal consumers had consistently higher diet quality (4–16 points higher HEI 2015 total score, p < 0.05), higher WG intake (0.6–1.6 oz eq. higher, p < 0.05), and higher fiber and magnesium intakes compared to consumers of most other breakfasts or breakfast skippers. The results show that children consuming oatmeal breakfasts have better diet quality and increased intake of key nutrients compared to breakfast skippers and other breakfast consumers and suggest oatmeal may represent an important component of a healthy childhood diet.

Effect of Oat and Tartary Buckwheat - Based Food on Cholesterol - Lowering and Gut Microbiota in Hypercholesterolemic Hamsters

The nutritional components in oat and tartary buckwheat had been assessed to have cholesterollowering effects. However, The effect of oat and tartary buckwheat based-food (OF) on cholesterol-lowering and gut microbiota in hypercholesterole hamsters was still limited studied because they are usually consumed in whole gran as well as after being processed. In this study, normal diets, high fat diet (HFD) with/without OF were fed to hamsters for 30 days respectively and growth parameters, metabolic parameters, and gut microbiota were investigated, respectively. It was found that OF significantly decreased plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-cholesterol), lowered liver TC, cholesterol ester (CE), and triglycerides (TG) concentrations, and increased fecal weight and bile acids (BA) concentrations, compared with HFD (p < 0.05). Moreover, the concentrations of acetate, propionate, butyrate and total short-chain fatty acids (SCFAs) were significantly increased in hamsters fed with OF, compared with HFD (p < 0.05). OF changed the overall structure of gut microbiota. The relative abundances of Erysipelotrichaceae, Ruminococcaceae, and Lachnospiraceae were decreased and the relative abundance of Eubacteriaceae was increased, compared with HFD. These results suggested that OF could reduce the concentrations of plasma lipid by inhibiting cholesterol absorption in liver and promoting excretions of fecal lipid and BA. And it also increased SCFAs and modulated the gut microbiota effectively to exert the hypocholesterolemic effects.

Processing of oat: the impact on oat's cholesterol lowering effect

Epidemiological and interventional studies have clearly demonstrated the beneficial impact of consuming oat and oat-based products on serum cholesterol and other markers of cardiovascular disease. The cholesterol-lowering effect of oat is thought to be associated with the β-glucan it contains. However, not all food products containing β-glucan seem to lead to the same health outcome. Overall, highly processed β-glucan sources (where the oat tissue is highly disrupted) appear to be less effective at reducing serum cholesterol, but the reasons are not well understood. Therefore, the mechanisms involved still need further clarification. The purpose of this paper is to review current evidence of the cholesterol-lowering effect of oat in the context of the structure and complexity of the oat matrix. The possibility of a synergistic action and interaction between the oat constituents promoting hypocholesterolaemia is also discussed. A review of the literature suggested that for a similar dose of β-glucan, (1) liquid oat-based foods seem to give more consistent, but moderate reductions in cholesterol than semi-solid or solid foods where the results are more variable; (2) the quantity of β-glucan and the molecular weight at expected consumption levels (∼3 g day-1) play a role in cholesterol reduction; and (3) unrefined β-glucan-rich oat-based foods (where some of the plant tissue remains intact) often appear more efficient at lowering cholesterol than purified β-glucan added as an ingredient.

Hypocholesterolemic and Prebiotic Effects of a Whole-Grain Oat-Based Granola Breakfast Cereal in a Cardio-Metabolic "At Risk" Population

Meta-analyses of randomized controlled trials (RTC) have confirmed the hypocholesterolaemic effect of oats and oat based fibers. However, the mechanisms by which oats or oat fractions lower cholesterol is not totally clear. Recognizing the important role of the gut microbiome in metabolism and metabolic disease risk, we examined the impact of whole grain oat Granola (WGO) on the human gut microbiota and cardio-metabolic risk factors using a randomized crossover dietary intervention in at risk individuals (ClinicalTrials.gov Identifier: NCT01925365). We randomized 32 individuals at risk of developing cardio-metabolic disease by virtue of mild hypercholesterolaemia or glucose intolerance, into two groups consuming either 45 g of WGO or non-whole grain (NWG) breakfast cereals daily for two 6-week intervention periods separated by a 4-week wash out period in a randomized, controlled, crossover, double-blinded design. Confirming the cholesterol lowering effect of WGO, we observed a significant time by treatment interaction, for total cholesterol (TC) (P = 0.0001) and LDL-cholesterol (LDL-C) (P = 0.02) compared to NWG. A significant time by treatment interaction was also observed for the relative abundance of fecal bifidobacteria (P = 0.0001), lactobacilli (P = 0.001) and total bacterial count (P = 0.008), which were all elevated after consumption of WGO. Daily consumption of WGO resulted in a prebiotic effect on the human gut microbiota composition and significant reductions in TC and LDL-C concentrations. Prebiotic modulation of the human gut microbiota may thus constitute a previously unrecognized mechanism contributing to the hypocholesterolaemic effects of whole grain oat Granola.

Effects of dietary oat proteins on cholesterol metabolism of hypercholesterolaemic hamsters

BACKGROUND

The aim of present study was to investigate the hypocholesterolaemic effects of oat proteins (OP) in hamsters fed with a hypercholesterolaemic diet. The hamsters were divided into five groups and fed with the experimental diets containing oat, OP, oat β-glucan (OG), or OP+OG for 30 days.

RESULTS

OP and the OG significantly lowered the concentrations of plasma low-density lipoprotein-cholesterol and liver total cholesterol (TC), and increased the excretion of faecal bile acid and TC. Plasma and liver TC in the OP+OG group were significantly lower than those in the OP or OG groups. Both OP and OG increased the activity of liver cholesterol 7α-hydroxylase (CYP7A1), while its activity in the OP+OG group was strongly increased compared with the OP or OG groups.

CONCLUSION

These results indicated that dietary OP could improve hypercholesterolaemia, while dietary OP and OG together would have better hypocholesterolaemic effects.

Bioactivity of a Rice Bran-Derived Peptide and its Sensory Evaluation and Storage Stability in Orange Juice

A pentapeptide prepared from rice bran demonstrated growth inhibition on human lung, liver, breast, and colon cancer cell lines. The objectives of this study were to evaluate the human prostate cancer growth inhibition by the pentapeptide and its 6-mo storage stability by incorporating spray-dried orange juice, and determining sensory acceptability. The pentapeptide showed inhibition of human prostate cancer cells by 45% at 460 μg/mL concentration. When incorporated in spray-dried orange juice, and reconstituted with water and tested, there was an approximately 10% degradation of the peptide at 620 μg/mL concentration under refrigerated conditions over a 6 mo storage period, whereas at ambient temperature the degradation was 30%. Larger degradation was observed when 240 or 460 μg/mL pentapeptide was used. Overall, consumer panelists liked sensory aspect of the reconstituted pentapeptide incorporated orange juice beverage. Also consumer panelists liked the color and mouthfeel attributes, their hedonic impression of flavor attribute was slightly low due to unpalatable bitter note caused by the presence of the peptide. Incorporation of the pentapeptide in spray-dried orange juice has the potential to serve as a functional food ingredient that can offer health benefits to consumers. It is possible that the structural instability can be minimized by encapsulation.

Effects of different cooking methods of oatmeal on preventing the diet-induced increase of cholesterol level in hypercholesterolemic rats

BACKGROUND

The aim of present study is to investigate the influences of brewing and boiling on hypocholesterolemic effect of oatmeal in rats fed with a hypercholesterolemic diet.

METHODS

Fifty-six male Sprague-Dawley rats were divided into 5 groups of 8 rats each with similar mean body weights and serum cholesterol concentrations. Rats were fed with the experimental diets containing 10% of oatmeal from two Chinese oat varieties which were brewed or boiled for 30 days. The lipids levels in serum, liver, and faeces were determined.

RESULTS

The effects of feeding boiled oatmeal on lowering lipid concentrations in plasma and liver were more significant than that of brewed oatmeal (P < 0.05). Feeding boiled oatmeal was also more efficient in increasing fecal total lipids, cholesterol and bile acids as compared to feeding brewed oatmeal (P < 0.05). Boiled oatmeal had higher apparent viscosity and soluble β-glucan content than the brewed oatmeal did (P < 0.05).

CONCLUSION

These results indicated that the capability of boiled oatmeal in improving cholesterol metabolism is better than that of brewed oatmeal, which is mainly attributed to its higher soluble β-glucan content and apparent viscosity.

Cooked oatmeal consumption is associated with better diet quality, better nutrient intakes, and reduced risk for central adiposity and obesity in children 2-18 years: NHANES 2001-2010

Background

None of the studies of whole grains that have looked either at diet or weight/adiposity measures have focused exclusively on oatmeal.

Objective

The objective of this study was to assess the association between oatmeal consumption and nutrient intake, diet quality, and weight/adiposity of children aged 2–18.

Design

A nationally representative sample of children aged 2–18 (N=14,690) participating in National Health and Nutrition Examination Survey 2001–2010 was used. Intake was determined from a single 24-h dietary recall. Diet quality was measured using the Healthy Eating Index-2010 (HEI-2010). Covariate-adjusted regression analyses, using appropriate sample weights, were used to determine differences between oatmeal consumers and non-consumers for demographics, nutrient intakes, diet quality, and weight/adiposity measures (p<0.01). Logistic regression was performed to calculate odds ratios for weight measures and obesity (p<0.05).

Results

Compared to non-consumers, oatmeal consumers were more likely to be younger and less likely to be smokers. Consumers had higher intakes of dietary fiber, vitamin A, thiamin, riboflavin, calcium, phosphorus, magnesium, iron, copper, and potassium, and significantly lower intakes of total, monounsaturated and saturated fatty acids, cholesterol, and sodium. Oatmeal consumers had higher dietary quality scores attributable to higher intakes of whole grains and lower intakes of refined grains and empty calories. Children consuming oatmeal were at lower risk for having central adiposity and being obese.

Conclusions

Consumption of oatmeal by children was associated with better nutrient intake, diet quality, and reduced risk for central adiposity and obesity and should be encouraged as part of an overall healthful diet.

Protective effects of oat oil on deltamethrin-induced reprotoxicity in male mice

Oats (Avena sativa L.), which are used in foods, are a potential economically viable source of oil. The purpose of this study was to determine the efficiency of oats oil to alleviate oxidative damage of testis induced by deltamethrin, which is a pyrethroid pesticide that exerts a wide range of effects on non-targeted organisms. The reprotoxicity caused by orally administered deltamethrin (DEL) to mice can be effectively antagonized by the beneficial effects of oats oil (OO) as an antioxidant. Thirty-two male albino mice were divided into four equal groups: a control group, a group of mice given deltamethrin (5 mg per kg b.w.), a group administered deltamethrin after receiving oats oil (6 g per kg b.w.), and a group receiving only OO. Exposure to deltamethrin at a dose of 5 mg per kg b.w. per day caused oxidative stress in testis, proven by a decrease in the epididymal sperm count and motility, an increase in the number of abnormal morphologies in spermatozoa and a significant increase of lipid peroxidation (LP) in the testis when compared to control animals. Co-administration of oats oil to the DEL-treated mice ameliorated the testicular biochemical parameters as well as the histological impairments in testis. We concluded that oats oil ameliorated the toxic effects of deltamethrin in testis explored by reduced LP and improved total sperm density, motility and morphology in mice spermatozoa, suggesting its role as a potential antioxidant.

Nutritional advantages of oats and opportunities for its processing as value added foods - a review

Oats (Avena sativa L.) have received considerable attention for their high content of dietary fibres, phytochemicals and nutritional value. It is believed that consumption of oats possesses various health benefits such as hypocholesterolaemic and anticancerous properties. Oats have also recently been considered suitable in the diet of celiac patients. Owing to their high nutritional value, oat-based food products like breads, biscuits, cookies, probiotic drinks, breakfast cereals, flakes and infant food are gaining increasing consideration. Research and development on oat and its products may be helpful in combating various diseases known to mankind. This paper provides an overview of the nutritional and health benefits provided by oats as whole grains and its value added products. It is designed to provide an insight on the processing of oats and its effect on their functional properties. The manuscript also reviews various uses of oats and its fractions for clinical and industrial purposes and in development of value added food products.

The cholesterol-lowering effects of oat varieties based on their difference in the composition of proteins and lipids

Background

The aim of present study is to investigate the hypocholesterolemic effects of the oat components other than the β-glucan in rats fed with a hypercholesterolemic diet.

Methods

Four-week-old male Wister rats were divided into 6 groups of 7 rats each with similar mean body weights and serum cholesterol concentrations. Rats were fed with the experimental diets containing 10% oats flour for 30 days. Food intake was recorded and monitored everyday to ensure the similar contents of protein, starch, lipid and cellulose in all groups. The lipids levels in serum, liver, and faeces were determined.

Results

The plasma total cholesterol concentrations in different oat groups were significantly reduced compared with the control group, and the effects were different among oat groups. The decrease extent of plasma total cholesterol and low-density lipoprotein-cholesterol concentrations increased with the increase of the proteins and lipids contents. Moreover, liver total cholesterol and cholesterol ester contents were markedly decreased. The fecal bile acids concentrations in the oat groups were significantly increased. Oat proteins had lower Lysine/Arginin (0.59 ~ 0.66) and Methionin/Glycine (0.27 ~ 0.35) ratio than casein (Lysine/Arginin, 2.33; Methionin/Glycine, 1.51). Oat lipids contained higher contents of total Vitamin E and plant sterols than that in soybean oil.

Conclusion

These results indicated that dietary oat improved hypercholesterolemia by increasing the excretions of fecal bile acids, and this improvement was not only related to β-glucan, but also attributed to the lipids and proteins. Oat proteins decreased serum total cholesterol and low-density lipoprotein-cholesterol contents due to their low Lysine/Arginin and Methionin/Glycine ratio. The co-existence of oleic acid, linoleic, vitamin E, or plant sterols accounted for the hypocholesterolemic properties of oat lipids.

The benefits of breakfast cereal consumption: a systematic review of the evidence base

There have been no comprehensive reviews of the relation of breakfast cereal consumption to nutrition and health. This systematic review of all articles on breakfast cereals to October 2013 in the Scopus and Medline databases identified 232 articles with outcomes related to nutrient intake, weight, diabetes, cardiovascular disease, hypertension, digestive health, dental and mental health, and cognition. Sufficient evidence was available to develop 21 summary evidence statements, ranked from A (can be trusted to guide practice) to D (weak and must be applied with caution). Breakfast cereal consumption is associated with diets higher in vitamins and minerals and lower in fat (grade B) but is not associated with increased intakes of total energy or sodium (grade C) or risk of dental caries (grade B). Most studies on the nutritional impact are cross-sectional, with very few intervention studies, so breakfast cereal consumption may be a marker of an overall healthy lifestyle. Oat-, barley-, or psyllium-based cereals can help lower cholesterol concentrations (grade A), and high-fiber, wheat-based cereals can improve bowel function (grade A). Regular breakfast cereal consumption is associated with a lower body mass index and less risk of being overweight or obese (grade B). Presweetened breakfast cereals do not increase the risk of overweight and obesity in children (grade C). Whole-grain or high-fiber breakfast cereals are associated with a lower risk of diabetes (grade B) and cardiovascular disease (grade C). There is emerging evidence of associations with feelings of greater well-being and a lower risk of hypertension (grade D), but more research is required.

'The way to a man's heart is through his gut microbiota'--dietary pro- and prebiotics for the management of cardiovascular risk

The human gut microbiota has been identified as a possible novel CVD risk factor. This review aims to summarise recent insights connecting human gut microbiome activities with CVD and how such activities may be modulated by diet. Aberrant gut microbiota profiles have been associated with obesity, type 1 and type 2 diabetes and non-alcoholic fatty liver disease. Transfer of microbiota from obese animals induces metabolic disease and obesity in germ-free animals. Conversely, transfer of pathogen-free microbiota from lean healthy human donors to patients with metabolic disease can increase insulin sensitivity. Not only are aberrant microbiota profiles associated with metabolic disease, but the flux of metabolites derived from gut microbial metabolism of choline, phosphatidylcholine and l-carnitine has been shown to contribute directly to CVD pathology, providing one explanation for increased disease risk of eating too much red meat. Diet, especially high intake of fermentable fibres and plant polyphenols, appears to regulate microbial activities within the gut, supporting regulatory guidelines encouraging increased consumption of whole-plant foods (fruit, vegetables and whole-grain cereals), and providing the scientific rationale for the design of efficacious prebiotics. Similarly, recent human studies with carefully selected probiotic strains show that ingestion of viable microorganisms with the ability to hydrolyse bile salts can lower blood cholesterol, a recognised risk factor in CVD. Taken together such observations raise the intriguing possibility that gut microbiome modulation by whole-plant foods, probiotics and prebiotics may be at the base of healthy eating pyramids advised by regulatory agencies across the globe. In conclusion, dietary strategies which modulate the gut microbiota or their metabolic activities are emerging as efficacious tools for reducing CVD risk and indicate that indeed, the way to a healthy heart may be through a healthy gut microbiota.

Chronic consumption of a wild green oat extract (Neuravena) improves brachial flow-mediated dilatation and cerebrovascular responsiveness in older adults

BACKGROUND

Heart health benefits have been attributed to regular consumption of oats. Preclinical evidence suggests that a wild green oat extract (WGOE) may improve vasodilator function, but this is yet to be evaluated in humans.

OBJECTIVE

To determine whether regular daily consumption of WGOE can influence vasodilator function in systemic and cerebral arteries.

METHODS

Thirty-seven healthy older adults (>60 years) completed a 24-week randomized, double-blind, placebo-controlled two-way crossover dietary intervention with 1500 mg/day of encapsulated WGOE or placebo. All assessments were conducted at the end of each 12-week intervention arm, after participants had fasted for at least 4 h and at least 18 h after they had taken their last dose of supplement. Flow-mediated dilatation (FMD) of the brachial artery and hypercapnia-induced increases of blood flow in the middle cerebral artery were used to measure systemic and cerebral vasodilator responsiveness (CVR), respectively.

RESULTS

Compared with placebo, WGOE supplementation increased CVR and FMD to a similar extent (42 and 41%, respectively, P < 0.01 for both). The improvements in CVR and FMD were not correlated. Resting blood pressure did not alter with supplementation. Dose and treatment duration were well tolerated by participants.

CONCLUSION

WGOE supplementation can improve vasodilator function in systemic and cerebral arteries, suggesting a potential role in the maintenance of cardiovascular health.

Molecular characterization of phospholipids by high-performance liquid chromatography combined with an evaporative light scattering detector, high-performance liquid chromatography combined with mass spectrometry, and gas chromatography combined with a flame ionization detector in different oat varieties

Oat (Avena sativa L.) is an important crop produced in various regions of Europe and North America. Oat lipids are a heterogeneous mixture of acyl lipids and unsaponifiable components. The neutral lipids are mainly triacylglycerols and account for 50-60% of total oat lipids. Oat oil is also rich in polar lipids, that is, phospholipids and glycolipids. Characterization of oat polar lipids has largely been performed by thin-layer chromatography (TLC), but the composition of phospholipid classes has been poorly studied. The aim of our work was the determination of different phospholipids in Romanian oat samples. For that purpose, one commercial sample (Comun) and four pure varieties (Jeremy, Lovrin 1, Lovrin 27-T, and Mures) were used. High-performance liquid chromatography combined with an evaporative light scattering detector results allowed us to establish that phosphatidylethanolamine was the most representative phospholipid in all of the oat samples. In addition, high-performance liquid chromatography combined with electrospray ionization mass spectrometry analysis showed that C16:0, C16:1, C18:0, C18:1, C18:2, C18:3, C20:0, and C20:1 were the fatty acids bound to the glycerol backbone. Using first-preparative TLC and later gas chromatography, it was demonstrated that linoleic acid (C18:2) was the main fatty acid of the phospholipid fraction in all of the samples.

Functional replacements for gluten

Celiac disease (CD) is an immune-mediated disease triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. Currently, the only therapy able to normalize the clinical and histological manifestation of the disease is a strict and life-long gluten-free (GF) diet. The replacement of gluten presents a significant technological challenge, as it is an essential structure-building protein, which is necessary for formulating high-quality baked goods. The objective of this paper is to review some basics about CD, its current prevalence, and the recent advances in the preparation of high-quality GF breads using GF flours, starches, hydrocolloids, gums, and novel functional ingredients and technologies.

Introduction of oats in the diet of individuals with celiac disease: a systematic review

Celiac disease is an immune-mediated disease, triggered in genetically susceptible individuals by ingested gluten from wheat, rye, barley, and other closely related cereal grains. The only treatment for celiac disease is a strict gluten-free diet for life. This paper presents a systematic review of the scientific literature on the safety of pure oats for individuals with celiac disease, which historically has been subject to debate. Limitations identified within the scientific database include: limited data on long-term consumption, limited numbers of participants in challenge studies, and limited reporting about the reasons for withdrawals from study protocols. Furthermore, some evidence suggests that a small number of individuals with celiac disease may be intolerant to pure oats and some evidence from in vitro studies suggests that an immunological response to oat avenins can occur in the absence of clinical manifestations of celiac disease as well as suggesting that oat cultivars vary in toxicity. Based on the majority of the evidence provided in the scientific database, and despite the limitations, Health Canada and the Canadian Celiac Association (CCA) concluded that the majority of people with celiac disease can tolerate moderate amounts of pure oats. The incorporation of oats into a gluten-free diet provides high fiber and vitamin B content, increased palatability, and beneficial effects on cardiovascular health. However, it is recommended that individuals with celiac disease should have both initial and long-term assessments by a health professional when introducing pure oats into a gluten-free diet.

Analysis of oil composition in cultivars and wild species of oat (Avena sp.)

Oil quality and content were analyzed in 33 accessions from 13 wild species and 10 accessions of cultivated oat. Wild oat species tended to have higher oil and 18:1 fatty acid (FA) contents and lower amounts of 18:2 and 18:3 FAs as compared to cultivated oats. In addition to common FAs, minor amounts of several hydroxy and epoxy FAs were also present in the oat oil and mainly confined to specific lipid classes. These unusual FAs included the previously reported 15-hydroxy 18:2 (Delta9,12) (avenoleic acid) mostly found among polar lipids and a novel 7-hydroxyhexadecanoic acid located to 1,2-diacylglycerol. The present study highlights the potential of making use of the existing germplasm, consisting of wild oat species, in breeding programs for achieving new oat varieties that produce a range of oils with different FA compositions as well as having high oil contents. However, in one matter, oats apparently lack genetic diversity and that is for oil qualities that are highly enriched in the omega 3 (omega-3) FA 18:3. Consequently, developing oat cultivars with highly unsaturated oils will need involvement of other techniques such as biotechnology.