Oats (Avena sativa) reduce atherogenesis in LDL-receptor-deficient mice

Impact of Oat (Avena sativa L.) on Metabolic Syndrome and Potential Physiological Mechanisms of Action: A Current Review

Oat (Avena sativa L.), an annual herbaceous plant belonging to the Gramineae family, is widely grown in various regions including EU, Canada, America, Australia, etc. Due to the nutritional and pharmacological values, oats have been developed into various functional food including fermented beverage, noodle, cookie, etc. Meanwhile, numerous studies have demonstrated that oats may effectively improve metabolic syndrome, such as dyslipidemia, hyperglycemia, atherosclerosis, hypertension, and obesity. However, the systematic pharmacological mechanisms of oats on metabolic syndrome have not been fully revealed. Therefore, in order to fully explore the benefits of oat in food industry and clinic, this review aims to provide up-to-date information on oat and its constituents, focusing on the effects on metabolic syndrome.

A new insight in immunomodulatory impact of botanicals in treating avian coccidiosis

Avian coccidiosis is caused by genus Eimeria (E.) i.e. E. maxima, E. necatrix, E. tenella, E. acervulina, E. brunette and E. mitis and lead to three billion US dollar per year economic loss in poultry industry and reduces the growth performance of birds. To purge undesirable foreign agents, immune system produces a variety of molecules and cells that ultimately neutralize target particles in healthy organisms. However; when this particular system compromises, infection develops and the load of pathogens along with their virulence factors overcome both; innate and adaptive immune systems. Livestock and poultry sectors are important part of agriculture industry worldwide. Due to excessive use of chemotherapeutic agents, pathogens have developed resistance against these agents leading to the great economic losses. Numerous therapeutic approaches are in routine process for the treatment and prevention of various ailments but irrational use of antibiotics/chemicals has raised alarming concerns, like the development of drug resistant strains, residual effects in ultimate users and environmental pollution. These problems have led to the development of alternatives. In this regard, anticoccidial vaccine can be used as an alternative but due to high cost of production, plant derived biological response modifiers and antioxidants compounds are considered as a promising alternative. This review summarizes the immunotherapeutic effects of different compounds particularly with reference to avian coccidiosis.

The Impact of Addition Oats (Avena sativa) and Cinnamon on Cookies and their Biological Effects on Rats Treated with Cirrhosis by CCL4

Oats are represented an important source for nutrition, and it have attracted a lot of attention in recent years. In this study we produced oatmeal cookies and oats was added to formula wheat by 50% and 75%. Also, we added cinnamon to treatments 3 and 4 by 5% to increase nutrition value of oatmeal cookies, improvement sensory evaluation and increase antioxidant properties. All the cookies treatments were storage at room temperature. The purposes of this study were to study antioxidant activity for oats and cinnamon. Also determined the chemical composition include (moisture content, protein, ash, total lipids, crude fibers, carbohydrates and total calories) for oats, white flour and oatmeal cookies treatments. In addition evaluated all of sensory evaluation contain (appearance, color, texture, taste and odor) and microbiological evaluation such as (total bacterial count, spore forming bacteria and mold and yeasts count) for oatmeal cookies treatments. Also, biological assays were preformed to measure level of GPT, GOT, urea, creatinine, total cholesterol, triglycerides, HDL, LDL, and glucose. Furthermore, histopathological examination of both liver and kidneys was analyzed. The obtained results were clarified that the antioxidant activity for oats and cinnamon were 52.91% and 87.91%. Moreover, addition of oats and cinnamon to the cookies improve sensory evaluation as made it more acceptable, decreasing microbial load principally treatments 4 (prepared by 75% oats + 5% cinnamon). Biochemical assays were improved in rats with cirrhosis of carbon tetrachloride and their histopathological examination of liver and kidneys. It was clear that the additions ground whole grain oats and cinnamon to wheat flour based cookies improve its nutritional, chemical, and biological functions properties.

A Review of Health-Beneficial Properties of Oats

Oat is among the food crops and ancient grains cultivated and consumed worldwide. It is gaining in popularity owing to its nutritional composition and multifunctional benefits of select bioactive compounds. Beta-glucan is an important component of dietary fiber found in oat grains. It is the major active compound in oats with proven cholesterol-lowering and antidiabetic effects. Oats also provide substantial levels of other bioactive compounds such as phenolic acids, tocols, sterols, avenacosides, and avenanthramides. The consumption of oats has been determined to be beneficial for human health by promoting immunomodulation and improving gut microbiota. In addition, oat consumption assists in preventing diseases such as atherosclerosis, dermatitis, and some forms of cancer. While much has been published in relation to oat nutrients and oat fibers and their impact on major diseases, the oat industries and consumers may benefit from greater knowledge and understanding of clinical effects, range of occurrence, distribution, therapeutic doses and food functional attributes of other oat bioactives such as avenanthramides and saponins as well as other anti-inflammatory agents found in the cereal. This review focuses on the various studies relevant to the contribution of the consumption of oats and oat-based products in preventing human diseases and promoting human health.

Effects of Bilberry and Oat intake on lipids, inflammation and exercise capacity after Acute Myocardial Infarction (BIOAMI): study protocol for a randomized, double-blind, placebo-controlled trial

Background

Bilberries from Sweden, rich in polyphenols, have shown cholesterol-lowering effects in small studies, and the cholesterol-lowering properties of oats, with abundant beta-glucans and potentially bioactive phytochemicals, are well established. Both may provide cardiometabolic benefits following acute myocardial infarction (AMI), but large studies of adequate statistical power and appropriate duration are needed to confirm clinically relevant treatment effects. No previous study has evaluated the potential additive or synergistic effects of bilberry combined with oats on cardiometabolic risk factors. Our primary objective is to assess cardioprotective effects of diet supplementation with dried bilberry or with bioprocessed oat bran, with a secondary explorative objective of assessing their combination, compared with a neutral isocaloric reference supplement, initiated within 5 days following percutaneous coronary intervention (PCI) for AMI.

Methods

The effects of Bilberry and Oat intake on lipids, inflammation and exercise capacity after Acute Myocardial Infarction (BIOAMI) trial is a double-blind, randomized, placebo-controlled clinical trial. A total of 900 patients will be randomized post-PCI to one of four dietary intervention arms. After randomization, subjects will receive beverages with bilberry powder (active), beverages with high-fiber bioprocessed oat bran (active), beverages with bilberry and oats combined (active), or reference beverages containing no active bilberry or active oats, for consumption twice daily during a 3-month intervention. The primary endpoint is the difference in LDL cholesterol change between the intervention groups after 3 months. The major secondary endpoint is exercise capacity at 3 months. Other secondary endpoints include plasma concentrations of biochemical markers of inflammation, metabolomics, and gut microbiota composition after 3 months.

Discussion

Controlling hyperlipidemia and inflammation is critical to preventing new cardiovascular events, but novel pharmacological treatments for these conditions are expensive and associated with negative side effects. If bilberry and/or oat, in addition to standard medical therapy, can lower LDL cholesterol and inflammation more than standard therapy alone, this could be a cost-effective and safe dietary strategy for secondary prevention after AMI.

Trial registration

ClinicalTrials.gov NCT03620266. Registered on August 8, 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05287-5.

β-Glucan Metabolic and Immunomodulatory Properties and Potential for Clinical Application

β-glucans are complex polysaccharides that are found in several plants and foods, including mushrooms. β-glucans display an array of potentially therapeutic properties. β-glucans have metabolic and gastro-intestinal effects, modulating the gut microbiome, altering lipid and glucose metabolism, reducing cholesterol, leading to their investigation as potential therapies for metabolic syndrome, obesity and diet regulation, gastrointestinal conditions such as irritable bowel, and to reduce cardiovascular and diabetes risk. β-glucans also have immune-modulating effects, leading to their investigation as adjuvant agents for cancers (solid and haematological malignancies), for immune-mediated conditions (e.g., allergic rhinitis, respiratory infections), and to enhance wound healing. The therapeutic potential of β-glucans is evidenced by the fact that two glucan isolates were licensed as drugs in Japan as immune-adjuvant therapy for cancer in 1980. Significant challenges exist to further clinical testing and translation of β-glucans. The diverse range of conditions for which β-glucans are in clinical testing underlines the incomplete understanding of the diverse mechanisms of action of β-glucans, a key knowledge gap. Furthermore, important differences appear to exist in the effects of apparently similar β-glucan preparations, which may be due to differences in sources and extraction procedures, another poorly understood issue. This review will describe the biology, potential mechanisms of action and key therapeutic targets being investigated in clinical trials of β-glucans and identify and discuss the key challenges to successful translation of this intriguing potential therapeutic.

The Cholesterol-Lowering Effect of Oats and Oat Beta Glucan: Modes of Action and Potential Role of Bile Acids and the Microbiome

Consumption of sufficient quantities of oat products has been shown to reduce host cholesterol and thereby modulate cardiovascular disease risk. The effects are proposed to be mediated by the gel-forming properties of oat β-glucan which modulates host bile acid and cholesterol metabolism and potentially removes intestinal cholesterol for excretion. However, the gut microbiota has emerged as a major factor regulating cholesterol metabolism in the host. Oat β-glucan has been shown to modulate the gut microbiota, particularly those bacterial species that influence host bile acid metabolism and production of short chain fatty acids, factors which are regulators of host cholesterol homeostasis. Given a significant role for the gut microbiota in cholesterol metabolism it is likely that the effects of oat β-glucan on the host are multifaceted and involve regulation of microbe-host interactions at the gut interface. Here we consider the potential for oat β-glucan to influence microbial populations in the gut with potential consequences for bile acid metabolism, reverse cholesterol transport (RCT), short-chain fatty acid (SCFA) production, bacterial metabolism of cholesterol and microbe-host signaling.

The benefit of secondary prevention with oat fiber in reducing future cardiovascular event among CAD patients after coronary intervention

There is limited information about the association between oat fiber intake and future cardiovascular events in CAD patients after coronary intervention for secondary prevention. This study enrolled 716 patients after coronary intervention in clinical stable status from the CAD cohort biosignature study. Patients were analyzed according to whether the presence of regular oat fiber intake during the follow-up period, and the association with endpoints including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and revascularization procedures were analyzed. The average follow-up period is 26.75 ± 8.11 months. Patients taking oat fiber were found to have lower serum levels of LDL, triglycerides, ratio of TC/HDL, as well as lower inflammatory markers values. After adjusting for confounders in the proportional hazard Cox model, oat fiber intake was associated with a lower risk of future revascularization (HR = 0.54, 95% CI 0.35–0.85; p = 0.007), and lower risk of major adverse cardiovascular events (HR = 0.62, 95% CI 0.43–0.88; p = 0.008), suggesting the association of oat fiber use and lower risk of future adverse event in CAD patients after coronary intervention.

Herbal Approach for Management of Atherosclerosis: a Review

PURPOSE OF REVIEW

Summarize of the reports on antioxidants especially from herbal sources which battle oxidative stress might be proficient to forestall and repair the free radical-prompted vascular damages in overseeing of atherosclerosis.

RECENT FINDINGS

Atherosclerosis is the one of the fundamental reason for hypertension, stroke, myocardial localized necrosis, and numerous other cardiovascular illnesses. Atherosclerosis associated path physiological factors like hypercholesterolemia, hypertension, diabetes mellitus, and smoking actuates oxidative stress which are characterized by excessive oxidation and improper exclusion. The herbal plant-based antioxidant agents are effective towards the management/treatment of atherosclerosis by different ways like, by diminishing the oxidation of low-density lipoproteins, diminishing the cell proliferation, restraining the foam cell arrangement, and advancing the reverse cholesterol transport, down regulation of pro-atherogenic genes, and inflammatory mediators. This review is a critical analysis about the role of oxidative stress in atherogenesis and furthermore outlines the ongoing study/examination done on the management of atherosclerosis by utilizing herbal antioxidant agents.

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.

Hypolipidaemic effects of oat flakes and β-glucans derived from four Chinese naked oat (Avena nuda) cultivars in Wistar-Lewis rats

BACKGROUND

β-Glucan is widely considered to be the major ingredient responsible for the hypolipidaemic effects of oat. Determination of the β-glucan content in naked oat cultivars in China has been largely performed for breeding and food processing. Since oat is generally consumed as oat flakes in China, evaluation of the bioactivity of oat flakes might be more direct and comprehensive than determination of the internal β-glucan. However, the hypolipidaemic activity of oat flakes processed from Chinese oat cultivars has rarely been reported.

RESULTS

The nutritional components of four naked oat cultivars were analysed before they were processed to oat flakes. The hypolipidaemic effects of oat flakes and the extracted β-glucans were tested on rats fed a high-fat diet for 30 days. Oat flakes and β-glucans of different origins showed different preventative effects on hyperlipidaemia. Among the four cultivars, β-glucan of 'Bayou-1' showed the greatest hypolipidaemic effect. However, oat flake processed from 'Dingyou-7' showed the best bioactivity to mediate the increase of serum lipid.

CONCLUSION

The hypolipidaemic effect of oat might not only depend on β-glucan, but might also be related to other components. 'Dingyou-7' might be suitable for oat flake processing because of its superior bioactivity.

GC-TOF-MS-based serum metabolomic investigations of naked oat bran supplementation in high-fat-diet-induced dyslipidemic rats

The present study aimed to explore the metabolic response of oat bran consumption in dyslipidemic rats by a high-throughput metabolomics approach. Four groups of Sprague-Dawley rats were used: N group (normal chow diet), M group (dyslipidemia induced by 4-week high-fat feeding, then normal chow diet), OL group and OH group (dyslipidemia induced, then normal chow diet supplemented with 10.8% or 43.4% naked oat bran). Intervention lasted for 12weeks. Gas chromatography quadrupole time-of-flight mass spectrometry was used to identify serum metabolite profiles. Results confirmed the effects of oat bran on improving lipidemic variables and showed distinct metabolomic profiles associated with diet intervention. A number of endogenous molecules were changed by high-fat diet and normalized following supplementation of naked oat bran. Elevated levels of serum unsaturated fatty acids including arachidonic acid (Log2Fold of change=0.70, P=.02 OH vs. M group), palmitoleic acid (Log2Fold of change=1.24, P=.02 OH vs. M group) and oleic acid (Log2Fold of change=0.66, P=.04 OH vs. M group) were detected after oat bran consumption. Furthermore, consumption of oat bran was also characterized by higher levels of methionine and S-adenosylmethionine. Pathway exploration found that most of the discriminant metabolites were involved in fatty acid biosynthesis, biosynthesis and metabolism of amino acids, microbial metabolism in diverse environments and biosynthesis of plant secondary metabolites. These results point to potential biomarkers and underlying benefit of naked oat bran in the context of diet-induced dyslipidemia and offer some insights into the mechanism exploration.

Quantitative assessment of the effects of beta-glucan consumption on serum lipid profile and glucose level in hypercholesterolemic subjects

BACKGROUND & AIMS

A growing body of evidence suggests that beta-glucan derived from oats or barley can reduce cardiovascular disease risk through reductions in serum lipids. However, the effects of beta-glucan on lipid changes in hypercholesterolemic patient groups are inconsistent. The objective of this study was to identify and quantify the effect of beta-glucan, a marker of water-soluble fiber, on various lipid parameters and glucose level in hypercholesterolemic subjects.

METHODS AND RESULTS

We performed a comprehensive literature search to identify the relevant randomized controlled trials (RCTs) that investigated the effects of beta-glucan consumption in hypercholesterolemic subjects. Mean differences (MDs) and 95% confidence intervals (CIs) were calculated for net changes in lipid concentrations by using fixed-effects or random-effects models according to heterogeneity. Publication bias, sensitivity analysis and subgroup analyses were also performed. Seventeen eligible RCTs with 916 subjects were included in the meta-analysis. The pooled result showed that beta-glucan consumption in hypercholesterolemic population significantly lowered the total cholesterol (TC) (MD, -0.26 mmol/L; 95% CI, -0.33 to -0.18; P < 0.00001) and low-density lipoprotein (LDL)-cholesterol concentration (MD, -0.21 mmol/L; 95% CI, -0.27 to -0.14; P < 0.00001). However, there were no significant differences in high-density lipoprotein (HDL)-cholesterol, triglycerides (TG) and glucose. No adverse effects were reported among the eligible trials.

CONCLUSION

Our meta-analysis showed that beta-glucan consumption significantly decreased TC and LDL-cholesterol concentrations but did not affect TG, HDL-cholesterol, and glucose concentrations in hypercholesterolemic subjects.

Rapid analysis of avenacosides in grain and husks of oats by UPLC-TQ-MS

Avenacosides A (AA) and B (AB) as well as 26-desglucoavenacoside A (26dAA) were quantified in oats using rapid and sensitive method utilising UPLC-TQ-MS. In the grain, AA and AB were revealed as the primary saponins, whereas in the husks, dAA was predominant. Inconsistent with the published data, observed concentrations of AA and AB in the grain were very similar. Presumably, this is due to higher sensitivity and better selectivity of the mass spectrometry-based quantification method, thus allowing for more precise measurements. Elevated level of an active fungicidal form of saponin, dAA in the husks possibly indicates they are more prone to fungal attacks.

Effects of Pediococcus parvulus 2.6 and its exopolysaccharide on plasma cholesterol levels and inflammatory markers in mice

Intake of dietary fibres may reduce the prevalence of physiological risk factors of the metabolic syndrome, such as high plasma lipid levels and low-grade inflammatory state. Dietary fibres are usually of plant origin however microbial exopolysaccharides (EPSs) have analogue structures that could potentially exert similar physiological effects. Pediococcus parvulus 2.6 (Pd 2.6) excretes a ropy EPS and has previously shown probiotic potential. The aim of this work was to evaluate physiological effects of Pd 2.6 and its EPS in vivo. The live Pd 2.6 (both the ropy and non-ropy isogenic variant) and its purified EPS were fed to hypercholesterolemic LDL-receptor deficient mice for 6 weeks to investigate their effects on cholesterol levels and the inflammatory tone of the animals. Both variants of Pd 2.6 survived passage through the mouse gut fulfilling an important criterion of probiotics. The ability to produce EPS was conferring an advantage to survival (faecal recovery of 3.7 (1.9-8.7) vs. 0.21 (0.14-0.34) *108 CFU, P < 0.001, median and 25th and 75th percentiles). The ropy Pd 2.6 decreased the levels of soluble vascular cell adhesion molecule-1 compared to the EPS alone (591 ± 14 vs. 646 ± 13 ng/ml, P < 0.05). An increase in liver weight in mice fed the purified EPS was observed, but with no change in liver lipids. No changes in blood lipids were detected in any group. Further the EPS induced growth of the caecal tissue and increased the amount of caecal content showing bulking properties like that of a dietary fibre.

Cholesterol-lowering effects of oat β-glucan

Elevated total and low-density lipoprotein (LDL) cholesterol levels are considered major risk factors for cardiovascular disease. Oat β-glucan, a soluble dietary fiber that is found in the endosperm cell walls of oats, has generated considerable interest due to its cholesterol-lowering properties. The United States Food and Drug Administration (FDA) approved a health claim for β-glucan soluble fiber from oats for reducing plasma cholesterol levels and risk of heart disease in 1997. Similarly, in 2004 the United Kingdom Joint Health Claims Initiative (JHCI) allowed a cholesterol-lowering health claim for oat β-glucan. The present review aims to investigate if results from more recent studies are consistent with the original conclusions reached by the FDA and JHCI. Results of this analysis show that studies conducted during the past 13 years support the suggestion that intake of oat β-glucan at daily doses of at least 3 g may reduce plasma total and low-density lipoprotein (LDL) cholesterol levels by 5-10% in normocholesterolemic or hypercholesterolemic subjects. Studies described herein have shown that, on average, oat consumption is associated with 5% and 7% reductions in total and LDL cholesterol levels, respectively. Significant scientific agreement continues to support a relationship between oat β-glucan and blood cholesterol levels, with newer data being consistent with earlier conclusions made by the FDA and JHCI.