Time-Dependent Indirect Antioxidative Effects of Oat Beta-Glucans on Peripheral Blood Parameters in the Animal Model of Colon Inflammation

Oat Beta-Glucan as a Metabolic Regulator in Early Stage of Colorectal Cancer-A Model Study on Azoxymethane-Treated Rats

Factors that reduce the risk of developing colorectal cancer include biologically active substances. In our previous research, we demonstrated the anti-inflammatory, immunomodulatory, and antioxidant effects of oat beta-glucans in gastrointestinal disease models. The aim of this study was to investigate the effect of an 8-week consumption of a diet supplemented with low-molar-mass oat beta-glucan in two doses on the antioxidant potential, inflammatory parameters, and colonic metabolomic profile in azoxymethane(AOM)-induced early-stage colorectal cancer in the large intestine wall of rats. The results showed a statistically significant effect of AOM leading to the development of neoplastic changes in the colon. Consumption of beta-glucans induced changes in colonic antioxidant potential parameters, including an increase in total antioxidant status, a decrease in the superoxide dismutase (SOD) activity, and a reduction in thiobarbituric acid reactive substance (TBARS) concentration. In addition, beta-glucans decreased the levels of pro-inflammatory interleukins (IL-1α, IL-1β, IL-12) and C-reactive protein (CRP) while increasing the concentration of IL-10. Metabolomic studies confirmed the efficacy of oat beta-glucans in the AOM-induced early-stage colon cancer model by increasing the levels of metabolites involved in metabolic pathways, such as amino acids, purine, biotin, and folate. In conclusion, these results suggest a wide range of mechanisms involved in altering colonic metabolism during the early stage of carcinogenesis and a strong influence of low-molar-mass oat beta-glucan, administered as dietary supplement, in modulating these mechanisms.

Consumption of Feed Supplemented with Oat Beta-Glucan as a Chemopreventive Agent against Colon Cancerogenesis in Rats

Colorectal cancer (CRC) accounts for 30% of all cancer cases worldwide and is the second leading cause of cancer-related deaths. CRC develops over a long period of time, and in the early stages, pathological changes can be mitigated through nutritional interventions using bioactive plant compounds. Our study aims to determine the effect of highly purified oat beta-glucan on an animal CRC model. The study was performed on forty-five male Sprague-Dawley rats with azoxymethane-induced early-stage CRC, which consumed feed containing 1% or 3% low molar mass oat beta-glucan (OBG) for 8 weeks. In the large intestine, morphological changes, CRC signaling pathway genes (RT-PCR), and proteins (Western blot, immunohistochemistry) expression were analyzed. Whole blood hematology and blood redox status were also performed. Results indicated that the histologically confirmed CRC condition led to a downregulation of the WNT/β-catenin pathway, along with alterations in oncogenic and tumor suppressor gene expression. However, OBG significantly modulated these effects, with the 3% OBG showing a more pronounced impact. Furthermore, CRC rats exhibited elevated levels of oxidative stress and antioxidant enzyme activity in the blood, along with decreased white blood cell and lymphocyte counts. Consumption of OBG at any dose normalized these parameters. The minimal effect of OBG in the physiological intestine and the high activity in the pathological condition suggest that OBG is both safe and effective in early-stage CRC.

Extraction, purification, structural characteristics, bioactivity and potential applications of polysaccharides from Avena sativa L.: A review

Avena sativa L. (A. sativa L.), commonly known as oat, is a significant cereal grain crop with excellent edible and medicinal value. Oat polysaccharides (OPs), the major bioactive components of A. sativa L., have received considerable attention due to their beneficial bioactivities. However, the isolation and purification methods of OPs lack innovation, and the structure-activity relationship remains unexplored. This review emphatically summarized recent progress in the extraction and purification methods, structural characteristics, biological activities, structure-to-function associations and the potential application status of OPs. Different materials and isolation methods can result in the differences in the structure and bioactivity of OPs. OPs are mainly composed of various monosaccharide constituents, including glucose, arabinose and mannose, along with galactose, xylose and rhamnose in different molar ratios and types of glycosidic bonds. OPs exhibited a broad molecular weight distribution, ranging from 1.34 × 105 Da to 4.1 × 106 Da. Moreover, structure-activity relationships demonstrated that the monosaccharide composition, molecular weight, linkage types, and chemical modifications are closely related to their multiple bioactivities, including immunomodulatory activity, antioxidant effect, anti-inflammatory activity, antitumor effects etc. This work can provide comprehensive knowledge, update information and promising directions for future exploitation and application of OPs as therapeutic agents and multifunctional food additives.

Combined Strategy Using High Hydrostatic Pressure, Temperature and Enzymatic Hydrolysis for Development of Fibre-Rich Ingredients from Oat and Wheat By-Products

Wheat bran (WB) and oat hull (OH) are two interesting undervalued cereal processing sources rich in total dietary fibre (TDF) and other associated bioactive compounds, such as β-glucans and polyphenols. The aim of this study was to optimise a combination chemical (enzymes) and physical (high hydrostatic pressure-temperature) strategies to increase the bioaccessibility of bioactive compounds naturally bound to the bran and hull outer layers. WB and OH were hydrolysed using food-grade enzymes (UltraFloXL and Viscoferm, for WB and OH, respectively) in combination with HPP at different temperatures (40, 50, 60 and 70 °C) and hydrolysis either before or after HPP. Proximal composition, phytic acid, β-glucans, total phenolics (TPs) and total antioxidant activity (TAC) were evaluated to select the processing conditions for optimal nutritional and bioactive properties of the final ingredients. The application of the hydrolysis step after the HPP treatment resulted in lower phytic acid levels in both matrices (WB and OH). On the other hand, the release of β-glucan was more effective at the highest temperature (70 °C) used during pressurisation. After the treatment, the TP content ranged from 756.47 to 1395.27 µmol GAE 100 g-1 in WB, and OH showed values from 566.91 to 930.45 µmol GAE 100 g-1. An interaction effect between the temperature and hydrolysis timing (applied before or after HPP) was observed in the case of OH. Hydrolysis applied before HPP was more efficient in releasing OH TPs at lower HPP temperatures (40-50 °C); meanwhile, at higher HPP temperatures (60-70 °C), hydrolysis yielded higher TP values when applied after HPP. This effect was not observed in WB, where the hydrolysis was more effective before HPP. The TP results were significantly correlated with the TAC values. The results showed that the application of optimal process conditions (hydrolysis before HPP at 60 or 70 °C for WB; hydrolysis after HPP at 70 °C for OH) can increase the biological value of the final ingredients obtained.

Low-molar-mass oat beta-glucan impacts autophagy and apoptosis in early stages of induced colorectal carcinogenesis in rats

Oat beta-glucan is one of the soluble dietary fibre fractions with a wide spectrum of biological activities such as anti-inflammatory and anti-tumour properties. In the present study, the effect of low-molar-mass oat beta-glucan isolate (OβGl) on the level of autophagy and apoptosis in the colorectum of rats with induced early stages of colorectal cancer was investigated. Forty-five male Sprague-Dawley rats were divided into two main groups: control and azoxymethane-induced early-stage colorectal carcinogenesis (CRC). Both groups were divided into three dietary subgroups fed standard feed without OβGl (OβGl-), with 1 % of OβGl (OβGl+1 %) or with 3 % of OβGl (OβGl+3 %). The expression of autophagy (LC3B, beclin-1) and apoptosis (caspase-3, cleaved caspase-3, BAX, BCL-2 and PARP-1) markers was determined by immunohistochemistry, Western blot and PCR analysis. The obtained results showed that the expression of LC3B, caspase-3 and cleaved caspase-3 in the CRC mucosa, and LC3B-II expression in the CRC wall were higher in the OβGl+3 % compared to the OβGl- rats. A higher BAX/BCL-2 ratio was also observed in the CRC OβGl+1 % rats compared to the other CRC animals. In summary, OβGl+3 % has a modulatory effect, stimulating autophagy and the extrinsic apoptosis pathway, while OβGl+1 % has a stimulatory effect on the intrinsic apoptosis pathway.

Encapsulation of Polyphenolic Compounds Based on Hemicelluloses to Enhance Treatment of Inflammatory Bowel Diseases and Colorectal Cancer

Inflammatory bowel diseases (IBD) and colorectal cancer (CRC) are difficult to cure, and available treatment is associated with troubling side effects. In addition, current therapies have limited efficacy and are characterized by high costs, and a large segment of the IBD and CRC patients are refractive to the treatment. Moreover, presently used anti-IBD therapies in the clinics are primarily aimed on the symptomatic control. That is why new agents with therapeutic potential against IBD and CRC are required. Currently, polyphenols have received great attention in the pharmaceutical industry and in medicine due to their health-promoting properties. They may exert anti-inflammatory, anti-oxidative, and anti-cancer activity, via inhibiting production of pro-inflammatory cytokines and enzymes or factors associated with carcinogenesis (e.g., matrix metalloproteinases, vascular endothelial growth factor), suggesting they may have therapeutic potential against IBD and CRC. However, their use is limited under both processing conditions or gastrointestinal interactions, reducing their stability and hence their bioaccessibility and bioavailability. Therefore, there is a need for more effective carriers that could be used for encapsulation of polyphenolic compounds. In recent years, natural polysaccharides have been proposed for creating carriers used in the synthesis of polyphenol encapsulates. Among these, hemicelluloses are particularly noteworthy, being characterized by good biocompatibility, biodegradation, low immunogenicity, and pro-health activity. They may also demonstrate synergy with the polyphenol payload. This review discusses the utility and potential of hemicellulose-based encapsulations of polyphenols as support for treatment of IBD and CRC.

Ulcerative colitis and thrombocytosis: Case report and literature review

RATIONALE

Ulcerative colitis (UC) is an autoimmune disease of unknown etiology, sometimes associated with anemia and thrombocytosis. Platelets (PLTs) play a role in amplifying inflammatory and immune responses in chronic inflammation. This study discusses the diagnosis and treatment of a case of UC combined with secondary thrombocytosis and reviews the relevant literature. We report an interaction between thrombocytosis and UC to raise clinicians' awareness of this condition.

PATIENT CONCERNS

In the current report, we discuss the case of a 30-year-old female patient who presented with frequent diarrhea and thrombocytosis.

DIAGNOSIS

Severe UC combined with intestinal infection was diagnosed based on colonoscopy and intestinal biopsy. The patient had a PLT count >450 × 109/L and was diagnosed with reactive thrombocytosis.

INTERVENTIONS AND OUTCOMES

The patient was discharged from the hospital in remission after receiving vedolizumab and anticoagulant treatment.

LESSONS

In patients with severe UC with thrombocytosis, clinicians should pay attention to PLTs promoting inflammatory progression, as well as screening for venous thromboembolism risk and prophylactic anti-venous thromboembolism therapy at the time of dosing to avoid adverse effects.

β-glucans: a potential source for maintaining gut microbiota and the immune system

The human gastrointestinal (GI) tract holds a complex and dynamic population of microbial communities, which exerts a marked influence on the host physiology during homeostasis and disease conditions. Diet is considered one of the main factors in structuring the gut microbiota across a lifespan. Intestinal microbial communities play a vital role in sustaining immune and metabolic homeostasis as well as protecting against pathogens. The negatively altered gut bacterial composition has related to many inflammatory diseases and infections. β-glucans are a heterogeneous assemblage of glucose polymers with a typical structure comprising a leading chain of β-(1,4) and/or β-(1,3)-glucopyranosyl units with various branches and lengths as a side chain. β-glucans bind to specific receptors on immune cells and initiate immune responses. However, β-glucans from different sources differ in their structures, conformation, physical properties, and binding affinity to receptors. How these properties modulate biological functions in terms of molecular mechanisms is not known in many examples. This review provides a critical understanding of the structures of β-glucans and their functions for modulating the gut microbiota and immune system.

Perspectives in the Application of High, Medium, and Low Molecular Weight Oat β-d-Glucans in Dietary Nutrition and Food Technology-A Short Overview

For centuries human civilization has cultivated oats, and now they are consumed in various forms of food, from instant breakfasts to beverages. They are a nutrient-rich food containing linear mixed-linkage (1 → 3) (1 → 4)-β-d-glucans, which are relatively well soluble in water and responsible for various biological effects: the regulation of the blood cholesterol level, as well as being anti-inflammatory, prebiotic, antioxidant, and tumor-preventing. Numerous studies, especially in the last two decades, highlight the differences in the biological properties of the oat β-d-glucan fractions of low, medium, and high molecular weight. These fractions differ in their features due to variations in bioavailability related to the rheological properties of these polysaccharides, and their association with food matrices, purity, and mode of preparation or modification. There is strong evidence that, under different conditions, the molecular weight may determine the potency of oat-extracted β-d-glucans. In this review, we intend to give a concise overview of the properties and studies of the biological activities of oat β-d-glucan preparations depending on their molecular weight and how they represent a prospective ingredient of functional food with the potential to prevent or modulate various pathological conditions.

Chemoprevention effect of the Mediterranean diet on colorectal cancer: Current studies and future prospects

Colorectal cancer (CRC) is the third most common cancer and the second most deadly cancer worldwide. Nevertheless, more than 70% of CRC cases are resulted from sporadic tumorigenesis and are not inherited. Since adenoma-carcinoma development is a slow process and may take up to 20 years, diet-based chemoprevention could be an effective approach in sporadic CRC. The Mediterranean diet is an example of a healthy diet pattern that consists of a combination of nutraceuticals that prevent several chronic diseases and cancer. Many epidemiological studies have shown the correlation between adherence to the Mediterranean diet and low incidence of CRC. The goal of this review is to shed the light on the anti-inflammatory and anti-colorectal cancer potentials of the natural bioactive compounds derived from the main foods in the Mediterranean diet.

Colon Expression of Chemokines and Their Receptors Depending on the Stage of Colitis and Oat Beta-Glucan Dietary Intervention-Crohn's Disease Model Study

Crohn’s disease (CD), a condition characterized by chronic inflammation of the gastrointestinal tract with alternating periods of exacerbation and remission, is becoming common around the world. This study aimed to analyze the molecular mechanisms underlying the anti-inflammatory properties of oat beta-glucans of varying molar masses by modulating the expression of chemokines and their receptors as well as other proteins related to both stages of TNBS (2,4,6-trinitrobenzosulfonic acid)-induced colitis, which is an animal model of CD. The experiment involved 96 Sprague–Dawley rats, which were divided into two main groups: control and TNBS-induced colitis. Both groups of rats were further divided into three dietary subgroups, which were fed with standard feed or feed supplemented with low- or high-molar-mass oat beta-glucans for 3 (reflecting acute inflammation) or 7 days (reflecting pre-remission). The gene expression of chemokines and their receptors in the colon wall was determined by RT-PCR, and the expression of selected proteins in the mucosa was determined by immunohistochemical analysis. The results showed that acute and pre-remission stages of colitis were characterized by the increased gene expression of seven chemokines and four chemokine receptors in the colon wall as well as disrupted protein expression of CXCL1, CCL5, CXCR2, CCR5, and OPN in the mucosa. The consumption of oat beta-glucans resulted in decreased expression of most of these genes and modulated the expression of all proteins, with a stronger effect observed with the use of high-molar-mass beta-glucan. To summarize, dietary oat beta-glucans, particularly those of high molar mass, can reduce colitis by modulating the expression of chemokines and their receptors and certain proteins associated with CD.

Immune Status and Hepatic Antioxidant Capacity of Gilthead Seabream Sparus aurata Juveniles Fed Yeast and Microalga Derived β-glucans

This work aimed to evaluate the effects of dietary supplementation with β-glucans extracted from yeast (Saccharomyces cerevisiae) and microalga (Phaeodactylum tricornutum) on gene expression, oxidative stress biomarkers and plasma immune parameters in gilthead seabream (Sparus aurata) juveniles. A practical commercial diet was used as the control (CTRL), and three others based on CTRL were further supplemented with different β-glucan extracts. One was derived from S. cerevisiae (diet MG) and two different extracts of 21% and 37% P. tricornutum-derived β-glucans (defined as Phaeo21 and Phaeo37), to give a final 0.06% β-glucan dietary concentration. Quadruplicate groups of 95 gilthead seabream (initial body weight: 4.1 ± 0.1 g) were fed to satiation three times a day for 8 weeks in a pulse-feeding regimen, with experimental diets intercalated with the CTRL dietary treatment every 2 weeks. After 8 weeks of feeding, all groups showed equal growth performance and no changes were found in plasma innate immune status. Nonetheless, fish groups fed β-glucans supplemented diets showed an improved anti-oxidant status compared to those fed CTRL at both sampling points (i.e., 2 and 8 weeks). The intestinal gene expression analysis highlighted the immunomodulatory role of Phaeo37 diet after 8 weeks, inducing an immune tolerance effect in gilthead seabream intestine, and a general down-regulation of immune-related gene expression. In conclusion, the results suggest that the dietary pulse administration of a P. tricornutum 37% enriched-β-glucans extract might be used as a counter-measure in a context of gut inflammation, due to its immune-tolerant and anti-oxidative effects.

Recent advances of cereal β-glucan on immunity with gut microbiota regulation functions and its intelligent gelling application

β-glucan from cereals such as wheat, barley, oats and rye are a water-soluble dietary fiber, which are composed of repeating (1→4)-β-bond β-D-glucopyranosyl units and a single (1→3)-β-D-bond separated unit. β-glucan has a series of physicochemical properties (such as viscosity, gelling properties, solubility, etc.), which can be used as a food gel and fat substitute. Its structure endows the healthy functions, including anti-oxidative stress, lowering blood glucose and serum cholesterol, regulating metabolic syndrome and exerting gut immunity via gut microbiota. Due to their unique structural properties and efficacy, cereal β-glucan are not only applied in food substrates in the food industry, but also in food coatings and packaging. This article reviewed the applications of cereal β-glucan in hydrogels, aerogels, intelligent packaging systems and targeted delivery carriers in recent years. Cereal β-glucan in edible film and gel packaging applications are becoming more diversified and intelligent in recent years. Those advances provide a potential solution based on cereal β-glucan as biodegradable substances for immune regulation delivery system and intelligent gelling material in the biomedicine field.

Clinical Outcomes after Oat Beta-Glucans Dietary Treatment in Gastritis Patients

The prevalence of gastritis in humans is constantly growing and a prediction of an increase in this health problem is observed in many countries. For this reason, effective dietary therapies are sought that can alleviate the course of this disease. The objective of this study was to determine the effect of chemically pure oat beta-glucan preparations with different molar masses, low or high, used for 30 days in patients with histologically diagnosed chronic gastritis. The study enrolled 48 people of both genders of different ages recruited from 129 patients with a gastritis diagnosis. Before and after the therapy, hematological, biochemical, immunological and redox balance parameters were determined in the blood and the number of lactic acid bacteria and SCFA concentrations in the feces. Our results demonstrated a beneficial effect of oat beta-glucans with high molar mass in chronic gastritis in humans, resulting in reduced mucosal damage and healthy changes in SCFA fecal concentration and peripheral blood serum glutathione metabolism and antioxidant defense parameters. This fraction of a highly purified oat beta-glucan is safe for humans. Its action is effective after 30 days of use, which sheds new light on the nutritional treatment of chronic gastritis.

Effects of Dietary Oat Beta-Glucans on Colon Apoptosis and Autophagy through TLRs and Dectin-1 Signaling Pathways-Crohn's Disease Model Study

Background: Crohn’s disease (CD) is characterized by chronic inflammation of the gastrointestinal tract with alternating periods of exacerbation and remission. The aim of this study was to determine the time-dependent effects of dietary oat beta-glucans on colon apoptosis and autophagy in the CD rat model. Methods: A total of 150 Sprague–Dawley rats were divided into two main groups: healthy control (H) and a TNBS (2,4,6-trinitrobenzosulfonic acid)-induced colitis (C) group, both including subgroups fed with feed without beta-glucans (βG−) or feed supplemented with low- (βGl) or high-molar-mass oat beta-glucans (βGh) for 3, 7, or 21 days. The expression of autophagy (LC3B) and apoptosis (Caspase-3) markers, as well as Toll-like (TLRs) and Dectin-1 receptors, in the colon epithelial cells, was determined using immunohistochemistry and Western blot. Results: The results showed that in rats with colitis, after 3 days of induction of inflammation, the expression of Caspase-3 and LC3B in intestinal epithelial cells did not change, while that of TLR 4 and Dectin-1 decreased. Beta-glucan supplementation caused an increase in the expression of TLR 5 and Dectin-1 with no changes in the expression of Caspase-3 and LC3B. After 7 days, a high expression of Caspase-3 was observed in the colitis-induced animals without any changes in the expression of LC3B and TLRs, and simultaneously, a decrease in Dectin-1 expression was observed. The consumption of feed with βGl or βGh resulted in a decrease in Caspase-3 expression and an increase in TLR 5 expression in the CβGl group, with no change in the expression of LC3B and TLR 4. After 21 days, the expression of Caspase-3 and TLRs was not changed by colitis, while that of LC3B and Dectin-1 was decreased. Feed supplementation with βGh resulted in an increase in the expression of both Caspase-3 and LC3B, while the consumption of feed with βGh and βGl increased Dectin-1 expression. However, regardless of the type of nutritional intervention, the expression of TLRs did not change after 21 days. Conclusions: Dietary intake of βGl and βGh significantly reduced colitis by time-dependent modification of autophagy and apoptosis, with βGI exhibiting a stronger effect on apoptosis and βGh on autophagy. The mechanism of this action may be based on the activation of TLRs and Dectin-1 receptor and depends on the period of exacerbation or remission of CD.

Neuroprotective Effects of Extracts from Tiger Milk Mushroom Lignosus rhinocerus Against Glutamate-Induced Toxicity in HT22 Hippocampal Neuronal Cells and Neurodegenerative Diseases in Caenorhabditis elegans

Despite the Tiger Milk Mushroom Lignosus rhinocerus (LR) having been used as a traditional medicine, little is known about the neuroprotective effects of LR extracts. This study aims to investigate the neuroprotective effect of three extracts of LR against glutamate-induced oxidative stress in mouse hippocampal (HT22) cells as well as to determine their effect in Caenorhabditis elegans. In vitro, we assessed the toxicity of three LR extracts (ethanol extract (LRE), cold-water extract (LRC) and hot-water extract (LRH)) and their protective activity by MTT assay, Annexin V-FITC/propidium iodide staining, Mitochondrial Membrane Potential (MMP) and intracellular ROS accumulation. Furthermore, we determined the expression of antioxidant genes (catalase (CAT), superoxide dismutase (SOD1 and SOD2) and glutathione peroxidase (GPx)) by qRT-PCR. In vivo, we investigated the neuroprotective effect of LRE, not only against an Aβ-induced deficit in chemotaxis behavior (Alzheimer model) but also against PolyQ40 formation (model for Morbus Huntington) in transgenic C. elegans. Only LRE significantly reduced both apoptosis and intracellular ROS levels and significantly increased the expression of antioxidant genes after glutamate-induced oxidative stress in HT22 cells. In addition, LRE significantly improved the Chemotaxis Index (CI) in C. elegans and significantly decreased PolyQ40 aggregation. Altogether, the LRE exhibited neuroprotective properties both in vitro and in vivo.