Rice bran extract mitigates depressive-like behavior in dextran sulfate sodium-induced colitis: Involvement of the gut-brain axis and Sirt1 signaling pathway

Inflammatory bowel disease (IBD) patients frequently suffer from depressive disorders as well. The present study was carried out to explore whether treatment with a standardized rice bran extract (RBE) could affect depression-like behavior in rats with dextran sulfate sodium (DSS)-induced colitis. Male Wistar rats were treated with RBE (100 mg/kg/day; p.o.) for 2 weeks. During the second week, colitis was induced by feeding the rats with 5 % (w/v) DSS in drinking water. RBE protected against DSS-induced body weight loss as well as against the macro- and microscopic inflammatory changes of the colon. Additionally, RBE mitigated DSS-induced dysregulation in blood-brain barrier tight junctional proteins, preserved the hippocampal histopathological architecture and improved the animal behavior in the forced swimming test. This was associated with modulation of hippocampal oxidative stress marker; GSH as well as hippocampal pro-inflammatory mediators; NF-ĸB and IL-1β. Treatment with RBE also led to a profound increase in the hippocampal levels of Sirt1, PGC-1α, Nrf2, and HO-1, which were drastically dropped by DSS. In conclusion, the study revealed the protective effect of RBE against DSS-induced depressive-like behavior through modulation of different parameters along the gut-brain axis and up-regulated the Sirt1/PGC-1α/Nrf2/HO-1 signaling pathway.

Fermented Rice Bran Supplementation Inhibits LPS-Induced Osteoclast Formation and Bone Resorption in Mice

Fermented rice bran (FRB) is known to have numerous beneficial bioactivities, amongst which is its anti-inflammatory properties when used as a supplement. To determine its effects, we examined osteoclastogenesis and bone resorption caused by injections of lipopolysaccharide (LPS), using mice with and without FRB supplementation. The results were favorable: those that received FRB showed reduced osteoclast numbers and bone resorption compared to those with the control diet. Notably, receptor activator of NF-κB ligand (RANKL) and tumor necrosis factor-α (TNF-α) mRNA levels were shown to be lower in the LPS-treated animals with FRB supplementation. FRB's inhibitory effect on RANKL- and TNF-α-induced osteoclastogenesis was further confirmed in vitro. In culture, macrophages exhibited decreased TNF-α mRNA levels when treated with FRB extract and LPS versus treatment with LPS alone, but there was no significant change in RANKL levels in osteoblasts. We can conclude that FRB supplementation dampens the effect of LPS-induced osteoclastogenesis and bone resorption by controlling TNF-α expression in macrophages and the direct inhibition of osteoclast formation.

Oryzanol Ameliorates DSS-Stimulated Gut Barrier Damage via Targeting the Gut Microbiota Accompanied by the TLR4/NF-κB/NLRP3 Cascade Response In Vivo

Inflammatory bowel disease (IBD) is a global chronic disease with a long duration and repeated relapse. Currently, there is still a lack of effective approaches to prevent IBD. Food-derived oryzanol (ORY) possesses extensive biological activities, such as ameliorating bowel diseases, antioxidation, and antiobesity. However, the mechanism of ORY in preventing colitis remains unclear. The present research aims to explore the potential mechanism of ORY in dextran sulfate sodium (DSS)-stimulated colitis in a rat model. The results showed that the symptoms of colitis were significantly improved with the administration of ORY. Mechanismly, the expression levels of Zonula occludens-1 (ZO-1), Claudin-1, Occludin, MUC2, and TFF3 were elevated through ORY treatment, suggesting that oral ORY relieved the degree of gut barrier damage of colitis rats. Meanwhile, 16S sequencing results found that ORY supplementation increased the abundances of Alloprevotella, Roseburia, Treponema, Muribaculaceae, and Ruminococcus, which are associated with the synthesis of short-chain fatty acids (SCFAs). Moreover, GC-MS results confirmed that ORY supplementation reversed the DSS-induced reduction of acetic acid, butyric acid, and total acid. Further research indicated that ORY intervention downregulated the TLR4/NF-κB/NLRP3 pathway, which is closely linked to the expression of proinflammatory cytokines and colon injury. Taken together, ORY ameliorates DSS-stimulated gut barrier damage and inflammatory responses via the gut microbiota-TLR4/NF-κB/NLRP3 signaling axis.

Integrated Technology for Cereal Bran Valorization: Perspectives for a Sustainable Industrial Approach

Current research focuses on improving the bioaccessibility of functional components bound to cereal bran cell walls. The main bioactive components in cereal bran that have major biological activities include phenolic acids, biopeptides, dietary fiber, and novel carbohydrates. Because of the bound form in which these bioactive compounds exist in the bran matrix, their bioaccessibility is limited. This paper aims to comprehensively analyze the functionality of an integrated technology comprising pretreatment techniques applied to bran substrate followed by fermentation bioprocesses to improve the bioaccessibility and bioavailability of the functional components. The integrated technology of specific physical, chemical, and biological pretreatments coupled with fermentation strategies applied to cereal bran previously-pretreated substrate provide a theoretical basis for the high-value utilization of cereal bran and the development of related functional foods and drugs.

Ethanol Extracts of Rice Bran and Whole Grain Adlay Seeds Mitigate Colonic Inflammation and Damage in Mice with Colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with frequent relapsing inflammation in the colon. Whole grains have been promoted as healthy and sustainable foods; however, the use of whole gains in UC is inconclusive. The aim of this study was to investigate the effects of ethanol extracts of rice bran (RBE) and whole-grain adlay seeds (ADE) on inflammation, oxidative stress, and colonic damage in UC. Male C57BL/6JNarl mice were intra-rectal injected twice with 2,4-dinitrobenzene sulfonic acid to induce (day 0) and reactivate (day 21) UC. Control mice were fed AIN-93M diet (R group) and injected with a vehicle. UC mice were fed AIN-93M diet (UC group) supplemented with RBE (RBE group) or ADE (ADE group) for 21 days. The results showed that the UC group had an increased disease activity index, plasma interleukin (IL)-6 and glutathione levels, microscopic injury scores, and inflammatory cytokine and chemokine levels in the colon and decreased colonic claudin-4 compared to the R group. RBE and ADE supplementation significantly reduced UC-elevated plasma IL-6 and colonic glutathione and pro-inflammatory cytokines and a chemokine. In addition, RBE and ADE supplementation significantly decreased T-helper-cell-associated cytokines in the plasma and colon. Moreover, RBE supplementation increased colonic IL-10 and tight junction protein claudin-4 levels, and ADE supplementation alleviated diarrhea in UC mice. In conclusion, these results suggest that RBE and ADE may mitigate colonic inflammation, oxidative stress, and damage in UC relapse.

Taxifolin as a Major Bioactive Compound in the Vasorelaxant Effect of Different Pigmented Rice Bran Extracts

Cardiovascular disease is one of the leading causes of morbidity and mortality in recent years. The intake of polyphenol rich diets has been associated with improved cardiovascular function and reduced cardiovascular risks. Oryza sativa L. is one of the most common cereals worldwide. Rice bran, a byproduct of the rice milling process, contains many bioactive ingredients, including polyphenols, polysaccharides, proteins, and micronutrients. It is also consumed as a healthy diet in the form of rice bran oil and powder in many Asian countries like Japan, South Korea, and India for its several health benefits as a natural antioxidant. Thus, this study evaluated the vasorelaxant effect of ethanolic extracts of brown, green, red, and black rice bran and investigated its underlying vasorelaxant mechanism. Among the four rice bran extracts (RBEs) examined, the red rice bran extract (RRBE) had a strong endothelium-dependent vasorelaxant effect, which was markedly prevented by N-ω-nitro-L-arginine [endothelial nitric oxide synthase (eNOS) inhibitor], wortmannin [phosphoinositide-3 kinase (PI3K) inhibitor], and 1H-[1,2,4]oxadiazole[4,3-alpha]quinoxalin-1-one (inhibitor of guanylate cyclase). Likewise, RRBE induced the phosphorylation of eNOS and Src in cultured endothelial cells, thereby stimulating NO formation. Altogether, these findings propose that RRBE induces endothelium-dependent relaxation, involving at least in part, NO-mediated signaling through the PI3K/eNOS pathway. Further, LC-PDA analysis conducted on the four RBEs also revealed that RRBE highly contained taxifolin, which is an active flavanonol that induces endothelium-dependent vasorelaxation, compared to other RBEs. Subsequently, the underlying mechanism of taxifolin was assessed through vascular reactivity studies with pharmacological inhibitors similar to that of RRBE. These findings deciphered a distinct difference in vasorelaxant effects between RRBE and the other RBEs. We also observed that RRBE induced a potent endothelium-dependent NO-mediated relaxation in coronary artery rings, which involved the Src/PI3K pathway that activates eNOS. Additionally, taxifolin exhibited, at least in part, similar vasoprotective effects of RRBE. Therefore, we propose that RRBE may serve as natural sources of functional phytochemicals that improve cardiovascular diseases associated with disturbed NO production and endothelial dysfunction.

Non-Targeted Dried Blood Spot-Based Metabolomics Analysis Showed Rice Bran Supplementation Effects Multiple Metabolic Pathways during Infant Weaning and Growth in Mali

Rice bran contains essential nutrients, antioxidants, and bioactives with anti-inflammatory and diarrheal protective properties important for infants. This 6-month randomized controlled trial investigated the effects of heat-stabilized rice bran supplementation during Malian infant weaning. Fifty healthy 6-month-old infants were randomized to a rice bran intervention (N = 25) or non-intervention control group (N = 25). Intervention infants received dose-escalating rice bran supplementation for 6 months (1–5 g/day). Monthly infant dried blood spot and anthropometric measurements were collected. Dried blood spot metabolite abundances were compared monthly according to diet for six months. Supplementation resulted in favorable weight-for-age and weight-for-length z-score changes. Non-targeted dried blood spot-based metabolomics identified 796 metabolites, of which 33% had significant fold differences between groups (7–12 months). Lipids and amino acids represented 70.6% of the metabolites identified. Rice bran supplementation during infant weaning significantly modulated the metabolites involved in antioxidant defenses and with neuroactive properties including reduced glutathione, glycine, glutamate, cysteinylglycine, tryptophan betaine, and choline. These findings support rice bran as a weaning ingredient to meet infant nutritional requirements and with the potential to reduce oxidative stress and improve cognitive outcomes. This study provides evidence for dried blood spots as a cost-effective tool to detect infant biomarkers of nutritional and metabolic status.

Changes in the Polyphenolic Profile and Antioxidant Activity of Wheat Bread after Incorporating Quinoa Flour

Quinoa is a trend and a promising functional food ingredient. Following previous research into the impact of incorporating quinoa flour on the polyphenol content and antioxidant activity of bread, this study aimed to bridge an existing gap about the qualitative and quantitative polyphenolic profiles of such bread. The UPLC-MS/MS analysis showed that quinoa bread, made with 25% quinoa flour of a black variety, presented more compounds than refined-wheat bread, and levels were remarkably higher in many cases. Consequently, the quinoa bread presented clearly improved polyphenolic content than the wheat bread (12.8-fold higher considering the sum of extractable and hydrolyzable polyphenols), as supported by greater antioxidant activity (around 3-fold). The predominant compounds in the extractable fraction of quinoa bread were p-hydroxybenzoic acid and quercetin (50- and 64-fold higher than in wheat bread, respectively) and rutin (not detected in wheat bread), while ferulic and sinapic acids were the most abundant compounds in the hydrolyzable fraction (7.6- and 13-fold higher than in wheat bread, respectively). The bread-making impact was estimated, and a different behavior for phenolic acids and flavonoids was observed. Extractable phenolic acids were the compounds that decreased the most; only 2 of 12 compounds were enhanced (p-hydroxybenozoic and rosmarinic acid with increments of 64% and 435%, respectively). Flavonoids were generally less affected, and their concentrations considerably rose after the bread-making process (7 of the 13 compounds were enhanced in the extractable fraction) with especially noticeably increases in some cases; e.g., apigenin (876%), kaempferol (1304%), luteolin (580%) and quercetin (4762%). Increments in some extractable flavonoids might be explained as a consequence of the release of the corresponding hydrolyzable forms. The present study provides new information on the suitability of quinoa-containing bread as a suitable vehicle to enhance polyphenols intake and, hence, the antioxidant activity in daily diets.

Protective and regenerative effects of a novel medical device against esophageal mucosal damage using in vitro and ex vivo models

Gastroesophageal reflux disease (GERD) is a common digestive disorder that causes esophagitis and injuries to the esophageal mucosa. GERD symptoms are recurrent during pregnancy and their treatment is focused on lifestyle changes and nonprescription medicines. The aim of this study was to characterize the mechanism of action of a new patented medical device, an oral formulation containing hyaluronic acid, rice extract, and amino acids dispersed in a bioadhesive polymer matrix, by assessing its protective effects in in vitro and ex vivo models of esophageal mucosa damage. Acidic bile salts and pepsin cocktail (BSC) added to CP-A and COLO-680 N esophagus cells were used as an in vitro GERD model to evaluate the binding capacities, anti-inflammatory effects and reparative properties of the investigational product (IP) in comparison to a viscous control. Our results showed that the IP prevents cell permeability and tight junction dysfunction induced by BSC. Furthermore, the IP was also able to down-regulate IL-6 and IL-8 mRNA expression induced by BSC stimulation and to promote tissue repair and wound healing. The results were confirmed by ex vivo experiments in excised rat esophagi through the quantification of Evans Blue permeability assay. These experiments provided evidence that the IP is able to bind to the human esophagus cells, preventing the damage caused by gastroesophageal reflux, showing potential anti-irritative, soothing, and reparative properties.

Rice Components with Immunomodulatory Function

Rice (Oryza sativa) is one of the most important food crops in the world, and the effect of its consumption on human health is of great concern. Evidence has accumulated that rice contains several components, such as γ-oryzanol and rice bran fibers, which modulate the immune system. In addition, rice has other immunologically beneficial characteristics. It has a low allergenic potential and is gluten-free, reducing the risk of development of food allergies and diseases related to gluten sensitivity such as coeliac disease. This review presents the recent advances in our understanding of the immunomodulatory function of rice components.