Health benefits of oat: current evidence and molecular mechanisms

Abstract

18Oat has historically been considered as a valuable crop due to its nutritional attributes. 19 In recent years, oat has attracted growing attention as a healthy food due to its content 20 of various bioactive compounds that can positively impact human health, such as β-21 glucan, avenanthramides, tocols, sterols, phytic acid and avenacosides. These 22 compounds are involved in the reduction of the risk of cardiovascular diseases (CVD), 23 type 2 diabetes mellitus (T2DM), gastrointestinal disorders and cancer. This short 24 review summarize the current knowledge about the beneficial effects of oat 25 consumption, with emphasis on oats bioactive compounds responsible of the health-26 promoting attributes of this cereal and their underlying molecular mechanisms. 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Oat has been recognized as a valuable foodstuff since ancient times, due to its 41 nutritional attributes. This cereal provides important amounts of carbohydrates, mainly 42 in the form of starch, dietary soluble fiber, lipids, good-balanced proteins and several B 43 vitamins. Recently, oat has received increased attention due to its health-related 44 benefits. Consumption of oat products has been associated to reduction of serum 45 cholesterol, and the risk of cardiovascular diseases (CVD), as well as with prevention of 46 cancer, diabetes and gastrointestinal disorders [1]. Based on clinical studies, the U. S 47 Food and Drug Administration and European Food and Safety Agency have approved 48 health claims for oat-derived foods regarding the ability of oat β-glucan (OBG) to 49 reduce the serum cholesterol and the risk of CVD [2,3]. However, the beneficial effects 50 of oat consumption have been attributed not only to the presence of OBG but also to 51 other bioactive compounds [1]. 52 Oat can be included among gluten-free ingredients when it is produced, prepared, and/or 53 processed in a way to avoid contamination with gluten-containing cereals [4]. However, 54 the careful selection of oat cultivar is crucial prior to its consumption by celiac people, 55 since the immunoreactivity associated with toxic prolamins depends on oat genotype 56 [5]. The inclusion of oat in gluten-free diets may improve the nutritional status of celiac 57 people and can offer a wider choice in their diets. 58 Despite the tremendous increase in oat popularity and consumption, its production has 59 declined steadily over the last years, especially in Europe, due to the dominance of other 60 cereals such as wheat and barley [6]. Nowadays the food industry is investing a great 61 deal of effort in increasing the usage of oat as ingredient for formulating novel food 62 products. The development of new oat products may increase the range of functional 63 foods in the market and could contribute to the prevention of chronic diseases. 64 This short review summarizes the current knowledge about the beneficial effects of oat 65 consumption, with emphasis on oat bioactive compounds responsible of the health-66 promoting attributes of this cerea...

Chemopreventive Effect of the Germinated Oat and Its Phenolic-AVA Extract in Azoxymethane/Dextran Sulfate Sodium (AOM/DSS) Model of Colon Carcinogenesis in Mice

“…Dietary fiber, with roughly 60% as insoluble fiber and 40% as soluble fiber [48], also decreases significantly during germination, since the release of gibberellin, a hormone capable of activating the enzyme β-glucanase, promotes β-glucan degradation, among other polysaccharides [17,49], which would explain the decrease in soluble fiber in our sample. Oats also contain other compounds such as phytic acid (5.6-8.7 mg/g; 0.56-0.87%) [9], which has its content decreased by 15%-35% during even a short three-day germination due to activation of phytase activity [50]. Although high doses of phytic acid inhibit the absorption of metals and minerals in humans, it has been observed that, in small doses, it can function as a protective factor in several chronic degenerative diseases [51]; therefore, current research only seeks to reduce the content of this antinutritional compound in various cereals.…”

“…In recent years, oats have attracted growing attention as a health food, involved in a lower risk of cardiovascular diseases (CVD), type 2 diabetes mellitus (T2DM), gastrointestinal disorders, and cancer [9]. Those properties have been attributed to their content of various bioactive compounds, such as β-glucan, the main component of the soluble fiber in oats.…”

“…In addition, oats have been associated with the presence of several antioxidant compounds, such as tocopherols and tocotrienols, which have the ability to act as strong free-radical scavengers, also showing the capacity to inhibit the proliferation of malignant colon cancer cells [12]. The inhibitory effects of avenacosides (oat-unique steroidal saponins) against the growth of human colon cells has also been evaluated through diverse mechanisms, such as the inhibition of tumor cell growth by cell cycle arrest and the stimulation of apoptosis, among others [9]. Moreover, phenolic compounds, such as ferulic acid and avenanthramides (AVA), are the most abundant components in oats and have documented antioxidant, anti-inflammatory, and antiproliferative activities [13,14].…”

Effects of Ultrasonication on the Antioxidant and Anti-diabetic Properties of Hydrolyzed Oat Proteins

“…6,7 . Human consumption has been increasing due to an increased awareness of the health benefits associated with the intake of oat products 4,8,9 . In 1998, the FDA recognized, based on available research data, that the consumption of 3 grams of soluble fibre from oats per day was sufficient to significantly decrease the risk of cardiovascular diseases 10 .…”

“…Since then, other studies have been conducted to determine the cholesterol-lowering properties of fibres from other cereals such as barley, however, those from oats are more efficient because of their high molecular weights. Today, more people are consuming oats and oat-related products containing brans or extracted fibres 8 . Oat products include bakery products, oatmeal, ready to eat breakfast cereals, flour, bran, and fibres 11 .…”