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Celiac disease is a chronic inflammatory autoimmune disease of the small bowel, and about 1% of the world's population is afflicted with celiac disease. To date, the most efficient treatment option is that the patient is required to strictly follow a gluten-free diet for their entire life, but it's difficult to adhere to and can lead to new nutritional imbalances, making it urgent to find novel nutritional interventions. Our aim was to explore the effects of nutritional intervention with quercetin on the celiac toxic effects of wheat gluten. This study systematically assessed the regulatory roles of quercetin on intestinal oxidative damage, immune response, inflammatory damage, and intestinal microflora dysbiosis in celiac disease by utilizing the established celiac in vitro and in vivo models induced by gluten. We discovered that quercetin could play a crucial role in intervening in celiac pathogenesis, not only owing to its antioxidant properties, but also because it modulates immune cell function and the intestinal microflora structure, particularly the regulation of Th1/Th2/Treg immune cell subpopulations and their functions, inhibition of the abundance of celiac disease marker flora such as Clostridium_celatum and Bacteroides_acidifaciens , and upregulation of the abundance of beneficial flora such as Butyricoccus_pullicaecorum and Bifidobacterium_longum , which ultimately worked together to ameliorate the celiac-related intestinal inflammation triggered by gluten. This study might provide new insights into the regulation of gut immunity and intestinal microflora homeostasis, as well as the potential application of quercetin in celiac disease.

Aims: We examined the cardiovascular effects of celiac disease (CeD) in a humanized mouse model, with a focus on vascular inflammation, endothelial dysfunction, and oxidative stress., Methods and Results: NOD.DQ8 mice genetically predisposed to CeD were subjected to a diet regime and oral gavage to induce the disease (gluten group vs. control). We tested vascular function, confirmed disease indicators, and evaluated inflammation and oxidative stress in various tissues. Plasma proteome profiling was also performed. CeD markers were confirmed in the gluten group, indicating increased blood pressure and impaired vascular relaxation. Pro-inflammatory genes were upregulated in this group, with increased CD11b + myeloid cell infiltration and oxidative stress parameters observed in aortic and heart tissue. However, heart function remained unaffected. Plasma proteomics suggested the cytokine interleukin-17A (IL-17A) as a link between gut and vascular inflammation. Cardiovascular complications were reversed by adopting a gluten-free diet., Conclusion: Our study sheds light in the heightened cardiovascular risk associated with active CeD, revealing a gut-to-cardiovascular inflammatory axis potentially mediated by immune cell infiltration and IL-17A. These findings augment our understanding of the link between CeD and cardiovascular disease providing clinically relevant insight into the underlying mechanism. Furthermore, our discovery that cardiovascular complications can be reversed by a gluten-free diet underscores a critical role for dietary interventions in mitigating cardiovascular risks associated with CeD., Competing Interests: Declaration of competing interest All authors declared no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: The increasing prevalence of food sensitivities has been attributed to changes in gut microenvironment; however, ubiquitous environmental triggers such as inorganic nanoparticles (NPs) used as food additives have not been thoroughly investigated., Objectives: We explored the impact of the NP-structured food-grade silicon dioxide ( f g - SiO 2 ) on intestinal immune response involved in oral tolerance (OT) induction and evaluated the consequences of oral chronic exposure to this food-additive using a mouse model of OT to ovalbumin (OVA) and on gluten immunopathology in mice expressing the celiac disease risk gene, HLA-DQ8., Methods: Viability, proliferation, and cytokine production of mesenteric lymph node (MLN) cells were evaluated after exposure to f g - SiO 2 . C57BL/6J mice and a mouse model of OT to OVA were orally exposed to f g - SiO 2 or vehicle for 60 d. Fecal lipocalin-2 (Lcn-2), anti-OVA IgG, cytokine production, and immune cell populations were analyzed. Nonobese diabetic (NOD) mice expressing HLA-DQ8 (NOD/DQ8), exposed to f g - SiO 2 or vehicle, were immunized with gluten and immunopathology was investigated., Results: MLN cells exposed to f g - SiO 2 presented less proliferative T cells and lower secretion of interleukin 10 (IL-10) and transforming growth factor beta ( TGF- β ) by T regulatory and CD 45 + CD 11 b + CD 103 + cells compared to control, two factors mediating OT. Mice given f g - SiO 2 exhibited intestinal Lcn-2 level and interferon gamma ( IFN- γ ) secretion, showing inflammation and less production of IL-10 and TGF- β . These effects were also observed in OVA-tolerized mice exposed to f g - SiO 2 , in addition to a breakdown of OT and a lower intestinal frequency of T cells. In NOD/DQ8 mice immunized with gluten, the villus-to-crypt ratio was decreased while the CD 3 + intraepithelial lymphocyte counts and the Th1 inflammatory response were aggravated after f g - SiO 2 treatment., Discussion: Our results suggest that chronic oral exposure to f g - SiO 2 blocked oral tolerance induction to OVA, and worsened gluten-induced immunopathology in NOD/DQ8 mice. The results should prompt investigation on the link between SiO 2 exposure and food sensitivities in humans. https://doi.org/10.1289/EHP12758.

Mutation breeding is among the most critical approaches to promoting genetic diversity when genetic diversity is narrowed for a long time using traditional breeding methods. In the current study, 15 wheat mutants created by gamma radiation and three salt-tolerant wheat cultivars were studied under no salinity stress (Karaj) and salinity stress (Yazd) during three consecutive growing seasons from 2017 to 2020 (M05 to M07 generations mutants). Results showed that salinity induced lipid peroxidation and enhanced ion leakage in all genotypes however, M6 and M15 showed the least ion leakage increment. It was also observed that the activity of antioxidant enzymes including SOD, CAT, POX, APX and GR increased with salinity; the maximum increase in antioxidant activity was belonged to M15, M09, M06 and M05. All genotypes had higher protein content in salinity stress conditions; M07 and M12 showed the lowest (1.8%) and the highest (17.3%) protein increase, respectively. Zeleny sedimentation volume increased under salinity stress conditions in all genotypes except M06, C2, C3, and M07. The result indicated that salinity stress increased wet gluten in all genotypes. M10 and M08 showed the highest (47.8%) and the lowest (4%) wet gluten increment, respectively. M06 and M11 mutants showed the lowest (6.1%) and the highest (60.7%) decrement of grain yield due to salinity stress, respectively. Finally, M04, M05, M07, M13, and M14 were known as genotypes with high grain yield in both no salinity and salinity stress conditions. In other word, these genotypes have higher yield stability. The results of the current study revealed that gamma irradiation could effectively be used to induce salinity tolerance in wheat., (© 2023. The Author(s).)

Scope: Western type of diets are characterized by high animal protein intake and are associated with various chronic inflammatory diseases. With a higher protein consumption, excess undigested protein will reach the colon and be subsequently metabolized by gut microbiota. Depending on the type of protein, fermentation in the colon generates different metabolites with varying biological effects. This study aims to compare the impact of protein fermentation products from different sources on gut health., Methods and Results: Three high protein diets (vital wheat gluten [VWG], lentil, or casein) are submitted to the in vitro model of colon. Fermentation of excess lentil protein for 72 h results in highest production of short-chain fatty acids and lowest production of branched-chain fatty acids. Exposure of Caco-2 monolayers or Caco-2 monolayers co-cultured with THP-1 macrophages to luminal extracts of fermented lentil protein results in less cytotoxicity of Caco-2 monolayers and less damage to barrier integrity, when compared to VWG and casein. Lowest induction of interleukin-6 is observed in THP-1 macrophages after treatment with lentil luminal extracts, which is identified to be regulated by aryl hydrocarbon receptor signaling., Conclusion: The findings indicate that protein sources affect the health effects of high protein diet in the gut., (© 2023 The Authors. Molecular Nutrition & Food Research published by Wiley-VCH GmbH.)

Drought stress is one of the most serious environmental stress factor constraining crop production across the globe. Among cereals, wheat grains are very sensitive to drought as a small degree of stress can affect the enzymatic system. This study aimed to investigate whether nitrogen and pre-anthesis drought priming could enhance the action of major regulatory enzymes involved in starch accumulation and protein synthesis in bread wheat (Triticum aestivum L.). For this purpose, cultivars YM-158 (medium gluten) and YM-22 (low gluten) were grown in rain-controlled conditions under two nitrogen levels, that is, N180 (N1) and N300 (N2). Drought priming was applied at the jointing stage and drought stress was applied 7 days after anthesis. Drought stress reduced starch content but enhanced protein content in grains. N2 and primed plants kept higher contents of nonstructural carbohydrates, fructans, and sucrose; with higher activity of sucrose-phosphate synthase in flag leaves. Furthermore, N2 and priming treatments showed higher sink ability to develop grains by showing higher sucrose-to-starch conversion activities of adenosine diphosphate-glucose pyrophosphorylase, uridine diphosphate glucose pyrophosphorylase, sucrose-synthase, soluble-starch synthase, starch branching enzyme, and granule-bound starch synthase as compared to N1 and non-primed treatments. The application of N2 and primed treatment showed a greater ability to maintain grain filling in both cultivars as compared to N1 and non-primed crops. Our study suggested that high nitrogen has the potential to enhance the effect of pre-drought priming to change source-sink relationships and grain yield of wheat under drought stress during the filling process., (© 2023 Scandinavian Plant Physiology Society.)

Preeclampsia (PE) is a disorder of pregnancy, which is categorized by hypertension and proteinuria or signs of end-organ damage. Though PE is the leading cause of maternal and fetal morbidity and mortality, the mechanisms leading to PE remain unclear. The present study examined the contribution of dietary protein source (casein versus wheat gluten) to the risk of developing maternal syndrome utilizing two colonies of Dahl salt-sensitive (SS/JrHsdMcwi) rats. While the only difference between the colonies is the diet, the colonies exhibit profound differences in the pregnancy phenotypes. The SS rats maintained on the wheat gluten (SSWG) chow are protected from developing maternal syndrome; however, approximately half of the SS rats fed a casein-based diet (SSC) exhibit maternal syndrome. Those SSC rats that develop pregnancy-specific increases in blood pressure and proteinuria have no observable differences in renal or placental immune profiles compared to the protected SS rats. A gene profile array of placental tissue revealed a downregulation in Nos3 and Cyp26a1 in the SSC rats that develop maternal syndrome accompanied with increases in uterine artery resistance index suggesting the source of this phenotype could be linked to inadequate remodeling within the placenta. Investigations into the effects of multiple pregnancies on maternal health replicated similar findings. The SSC colony displayed an exacerbation in proteinuria, renal hypertrophy and renal immune cell infiltration associated with an increased mortality rate while the SSWG colony were protected highlighting how dietary protein source could have beneficial effects in PE., (Copyright © 2021 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.)

Celiac disease is activated by digestion-resistant gluten peptides that contain immunogenic epitopes. Sourdough fermentation is a potential strategy to reduce the concentration of these peptides within food. However, we currently know little about the effect of partial sourdough fermentation on immunogenic gluten. This study examined the effect of a single sourdough culture (representative of those that the public may consume) on the digestion of immunogenic gluten peptides. Sourdough bread was digested via the INFOGEST protocol. Throughout digestion, quantitative and discovery mass spectrometry were used to model the kinetic release profile of key immunogenic peptides and profile novel peptides, while ELISA probed the gluten's allergenicity. Macrostructural studies were also undertaken. Sourdough fermentation altered the protein structure, in vitro digestibility, and immunogenic peptide release profile. Interestingly, sourdough fermentation did not decrease the total immunogenic peptide concentration but altered the in vitro digestion profile of select immunogenic peptides. This work demonstrates that partial sourdough fermentation can alter immunogenic gluten digestion, and is the first study to examine the in vitro kinetic profile of immunogenic gluten peptides from sourdough bread.

Non-celiac gluten sensitivity is often clinically indistinguishable from celiac disease, and patients show improvement or resolution of their symptoms with a gluten-free diet. In contrast to celiac disease, the effects of gluten on the skin and hair in the context of non-celiac gluten sensitivity are not as clear. This review aims to describe the impact of gluten on the skin and hair in patients with non-celiac gluten sensitivity and those without a definitive celiac disease diagnosis. A literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) reporting guidelines for systematic reviews. Forty-two publications met inclusion criteria with five studies describing the skin manifestations of non-celiac gluten sensitivity. Trials identifying the impact of a gluten-free diet on skin disease, as well as dermatologic conditions and their associations with antigliadin antibodies were also identified. Dermatologic manifestations in patients with non-celiac gluten sensitivity vary and may be non-specific. It may be appropriate for some of these patients with skin manifestations to trial a gluten-free diet. Dermatologic conditions that may respond positively to a gluten-free diet include psoriasis, atopic dermatitis, vitiligo, and palmoplantar pustulosis, while linear IgA disease does not appear to improve with this dietary change.

This study aimed to focus on the high-value utilization of raw wheat gluten by determining the potent antioxidant peptides and angiotensin I-converting enzyme (ACE) inhibitory peptides from wheat gluten oligopeptides (WOP). WOP were analyzed for in vitro antioxidant activity and inhibition of ACE, and the identification of active peptides was performed by reversed-phase high-performance liquid chromatography and mass spectrometry. Quantitative analysis was performed for highly active peptides. Five potent antioxidant peptides, Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (6.07 ± 0.38, 7.28 ± 0.29, 11.18 ± 1.02, 5.93 ± 0.20 and 9.04 ± 0.47 mmol 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) equivalent/g sample, respectively), and five potent ACE inhibitory peptides, Leu-Tyr, Leu-Val-Ser, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (half maximal inhibitory concentration (IC 50 ) values = 0.31 ± 0.02, 0.60 ± 0.03, 2.00 ± 0.13, 1.47 ± 0.08 and 1.48 ± 0.11 mmol/L, respectively), were observed. The contents of Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser were 155.04 ± 8.36, 2.08 ± 0.12, 1.95 ± 0.06, 22.70 ± 1.35, 0.25 ± 0.01, and 53.01 ± 2.73 μg/g, respectively, in the WOP. Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser are novel antioxidative/ACE inhibitory peptides that have not been previously reported. The results suggest that WOP could potentially be applied in the food industry as a functional additive.

The objective was to evaluate the mechanisms of digested total proteins (DTP), albumin, glutelin, and pure peptides from chia seed ( Salvia hispanica L.) to prevent adipogenesis and its associated inflammation in 3T3-L1 adipocytes. Preadipocytes (3T3-L1) were treated during differentiation with either DTP or digested albumin or glutelin (1 mg/mL) or pure peptides NSPGPHDVALDQ and RMVLPEYELLYE (100 µM). Differentiated adipocytes also received DTP, digested albumin or glutelin (1 mg/mL), before (prevention) or after (inhibition) induced inflammation by addition of conditioned medium (CM) from inflamed macrophages. All treatments prevented adipogenesis, reducing more than 50% the expression of PPARγ and to a lesser extent lipoprotein lipase (LPL), fatty acid synthase (FAS), sterol regulatory element-binding protein 1 (SREBP1), lipase activity and triglycerides. Inflammation induced by CM was reduced mainly during prevention, while DTP decreased expression of NF-κB (-48.4%), inducible nitric oxide synthase (iNOS) (-46.2%) and COX-2 (-64.5%), p < 0.05. Secretions of nitric oxide, PGE2 and TNFα were reduced by all treatments, p < 0.05. DTP reduced expressions of iNOS (-52.1%) and COX-2 (-66.4%). Furthermore, digested samples and pure peptides prevented adipogenesis by modulating PPARγ and additionally, preventing and even inhibiting inflammation in adipocytes by inhibition of PPARγ and NF-κB expression. These results highlight the effectiveness of digested total proteins and peptides from chia seed against adipogenesis complications in vitro.

There is a need to assess the relationship between improved rheological properties and the immunogenic potential of wheat proteins. The present study aimed to investigate the in vitro effects of total protein extracts from three modern and two landrace Triticum aestivum commercial flour mixes, with significant differences in gluten strength (GS), on cell lines. Cytotoxicity and innate immune responses induced by wheat proteins were investigated using Caco-2 monocultures, two dimensional (2D) Caco-2/U937 co-cultures, and three dimensional (3D) co-cultures simulating the intestinal mucosa with Caco-2 epithelial cells situated above an extra-cellular matrix containing U937 monocytes and L929 fibroblasts. Modern wheat proteins, with increased GS, significantly reduced Caco-2 cell proliferation and vitality in monoculture and 2D co-cultures than landrace proteins. Modern wheat proteins also augmented Caco-2 monolayer disruption and tight junction protein, occludin, redistribution in 3D co-cultures. Release of interleukin-8 into the cell medium and increased U937 monocyte migration in both 2D and 3D co-cultures were similarly apparent. Immuno-activation of migrating U937 cells was evidenced from cluster of differentiation 14 (CD14) staining and CD11b-related differentiation into macrophages. The modern wheat proteins, with gluten polymorphism relatedness and increased GS, were shown to be more cytotoxic and immunogenic than the landrace wheat proteins.

Background: In patients with coeliac disease, FODMAPs in gluten-containing foods, and participant anticipation of a harmful ('nocebo') effect, may contribute to acute symptoms after gluten challenge., Aim: To establish acute gluten-specific symptoms linked to immune activation in coeliac disease METHODS: We included 36 coeliac disease patients on a gluten-free diet receiving placebo in the RESET CeD trial. Double-blind, bolus vital wheat gluten (~6-g gluten protein) and sham challenges low in FODMAPs were consumed 2 weeks apart. Assessments included daily Coeliac Disease Patient Reported Outcome (CeD PRO) symptom scores (0-10), adverse events and serum interleukin-2 (baseline and 4 hours)., Results: Median CeD PRO score for nausea increased most (sham: 0 vs gluten: 5.5; P < .001). Apart from tiredness (1 vs 4, P = .005) and headache (0 vs 2, P = .002), changes in other symptoms were small or absent. Only nausea increased significantly in occurrence with gluten (11% vs 69%, P < .001). Without nausea, only tiredness and flatulence were common after gluten. Nausea (6% vs 61%, P < .001; median onset: 1:34 hours) and vomiting (0% vs 44%, P < .001; 1:51 hours) were the only adverse events more common with gluten than sham. Interleukin-2 was always below the level of quantitation (0.5 pg/mL) at baseline, and after sham. Interleukin-2 was elevated after gluten in 97% of patients (median fold-change: 20), and correlated with severity of nausea (r s  = .49, P = .0025) and occurrence of vomiting (P = .0005)., Conclusions: Nausea and vomiting are relatively specific indicators of acute gluten ingestion, and correlate with immune activation. IBS-like symptoms without nausea are unlikely to indicate recent gluten exposure., (© 2019 John Wiley & Sons Ltd.)

The gut microbiota plays a relevant role in determining an individual's health status, and the diet is a major factor in modulating the composition and function of gut microbiota. Gluten constitutes an essential dietary component in Western societies and is the environmental trigger of celiac disease. The presence/absence of gluten in the diet can change the diversity and proportions of the microbial communities constituting the gut microbiota. There is an intimate relation between gluten metabolism and celiac disease pathophysiology and gut microbiota; their interrelation defines intestinal health and homeostasis. Environmental factors modify the intestinal microbiota and, in turn, its changes modulate the mucosal and immune responses. Current evidence from studies of young and adult patients with celiac disease increasingly supports that dysbiosis (i.e., compositional and functional alterations of the gut microbiome) is present in celiac disease, but to what extent this is a cause or consequence of the disease and whether the different intestinal diseases (celiac disease, ulcerative colitis, Crohn disease) have specific change patterns is not yet clear. The use of bacterial-origin enzymes that help completion of gluten digestion is of interest because of the potential application as coadjuvant in the current treatment of celiac disease. In this narrative review, we address the current knowledge on the complex interaction between gluten digestion and metabolism, celiac disease, and the intestinal microbiota., (Copyright © American Society for Nutrition 2019.)

Scope: Cereals are important sources of carbohydrates, but also contain nutrients that could impact adiposity. The contribution of gluten to obesity and the effects of prebiotics-arabinoxylo-oligosaccharides (AXOS) and fructo-oligosaccharides (FOS)-that can be extracted from gluten-containing cereals are analyzed., Methods and Results: Mice are fed a control diet, Western diet (WD, consisting of high fat/high sucrose), or WD with 5% gluten. Prebiotics are tested in the WD with gluten. Gluten does not increase body weight and has a minor effect on ileal inflammation. Gluten decreases the expression of browning markers in the fat and increases the triglycerides synthesis in the muscle. AXOS decreases body weight and adiposity in fat pads muscle and liver. AXOS promotes gluten cleavage by the induction of prolyl endopeptidase that is translated into a reduction of gluten immunogenic peptides. Gluten has minor effects on cecal microbiota composition, whereas prebiotics increased Bifidobacterium, Butyricicoccus, Prevotella, and Parasutterella, which are all negatively correlated to the cecal content of gluten peptides., Conclusion: While gluten may affect metabolic homeostasis, these effects are lessened when gluten is consumed along with cereal-derived fibers. If confirmed in humans, the authors bring new arguments to eat fiber-rich cereals to promote a healthy diet., (© 2019 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Scope: The objectives are to evaluate the anti-inflammatory and anti-atherosclerotic effects of digested total protein and digested protein fractions from chia seed in macrophages in vitro., Methods and Results: Total protein and protein fractions (albumin, globulin, glutelin, and prolamin) are isolated from chia seed and digested using simulated gastrointestinal conditions, resulting in digested total protein (DTP) and digested protein fractions (DPF). DTP and DPF are applied (1.0 mg mL -1 ) in RAW 264.4 macrophages stimulated with LPS (1 µg mL -1 ) for inflammation or ox-LDL (80 µg mL -1 ) for atherosclerosis. In the inflammatory process, DTP and DPF reduce p-NF-κB, iNOS, p-JNK, and AP-1. Digested glutelin reduces the secretion of nitric oxide (65.1%), reactive oxygen species (19.7%), prostaglandins (34.6%), TNF-α (24.1%), MCP-1 (18.9%), IL-6 (39.6%), and IL-10 (68.7%). DTP and DPF reduce the NF-κB translocation to nuclei. DTP and digested glutelin reduce iCAM expression (86.4%, 80.8%), LOX-1 (37.3%, 35.7%), iNOS (67.0%, 42.2%), and NF-κB (57.5%, 71.1%). DTP is effective in reducing secretion of nitric oxide (43.4%), lipid accumulation (41.9%), prostaglandins (41.9%), TNF-α (43.3%), MCP-1 (47.6%), and IL-6 (50.5%). Peptides from chia DTP and DPF are also characterized., Conclusion: DTP and digested glutelin from chia seed reduce expression and secretion of markers related to inflammation and atherosclerosis pathways., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The objective of this study was to investigate the porcine pancreatic α-amylase (PPA) inhibitory activity of botanical food proteins, represented by soy protein isolate (SPI) and wheat gluten protein (WGP). The half maximal inhibitory concentration (IC 50 ) was determined, and the kinetics of inhibition were investigated using Dixon, Cornish-Bowden, and Lineweaver-Burk plots. The results showed WGP functioned as mixed-type inhibitors with both competitive and uncompetitive inhibitory characteristics, while SPI showed competitive inhibitory effects on α-amylase. The competitive inhibition constants (K ic ) of WGP and SPI were 5.753 and 30.212 mg/mL, respectively, and the uncompetitive inhibition constants (K iu ) of WGP was 45.110 mg/mL, respectively. The IC 50 values of WGP and SPI were 3.086 and 33.899 mg/mL, respectively. For WGP, the lower K ic vs. K iu for mixed-type inhibitors suggested that they bound more tightly to free PPA than the PPA-starch complex. Compared with SPI, WGP displayed a stronger inhibitory effect on α-amylase. These results indicated that SPI and WGP may delay the digestion of starchy foods by inhibiting starch hydrolytic enzymes, which may be of relevance in vivo during gastrointestinal digestion. The findings are also of important practical value for the development of carbohydrate-restricted diet and protein-based functional foods., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Celiac disease (CD) is an immune-mediated disorder triggered by gluten exposure. The contribution of the adaptive immune response to CD pathogenesis has been extensively studied, but the absence of valid experimental models has hampered our understanding of the early steps leading to loss of gluten tolerance. Using intestinal organoids developed from duodenal biopsies from both non-celiac (NC) and celiac (CD) patients, we explored the contribution of gut epithelium to CD pathogenesis and the role of microbiota-derived molecules in modulating the epithelium's response to gluten. When compared to NC, RNA sequencing of CD organoids revealed significantly altered expression of genes associated with gut barrier, innate immune response, and stem cell functions. Monolayers derived from CD organoids exposed to gliadin showed increased intestinal permeability and enhanced secretion of pro-inflammatory cytokines compared to NC controls. Microbiota-derived bioproducts butyrate, lactate, and polysaccharide A improved barrier function and reduced gliadin-induced cytokine secretion. We concluded that: (1) patient-derived organoids faithfully express established and newly identified molecular signatures characteristic of CD. (2) microbiota-derived bioproducts can be used to modulate the epithelial response to gluten. Finally, we validated the use of patient-derived organoids monolayers as a novel tool for the study of CD.

Starch-containing food normally has complex components and structure, which control its digestion kinetic properties and nutritional value. However, interactions among multiple food components and their effects on starch digestion kinetics are rarely reported. Here, we evaluated the influence of tea polyphenols [i.e., (-)-epigallocatechin (EGC) and (-)‑epigallocatechin‑3‑gallate (EGCG)] on the in vitro digestion rate and extent of wheat starch in the presence of gluten under uncooked and cooked conditions. The addition of EGC (20%, starch basis) did not change the starch digestion rate and extent for both uncooked and cooked physical forms in the presence and absence of gluten, whereas EGCG (20%, starch basis) significantly reduced the digestion extent of wheat starch by 25-30% in the absence of gluten and by 6.6-18.5% in the presence of gluten, a phenomenon that was caused by the reduced effective EGCG due to its interaction with gluten., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The objective of this research was to evaluate the effect of wheat gluten on gut microbiota from hamsters and also analyse whether alterations in microbiota could result in wheat gluten's lipid-lowering properties. Four weeks male hamsters were divided into 3 groups (n=10). Two hypercholesterolemic groups were fed for 35 days with hypercholesterolemic diet, containing 20% (w/w) wheat gluten or casein. Wheat gluten significantly reduced serum total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) concentrations, and also decreased the liver total cholesterol (TC), free cholesterol (FC), cholesterol ester (CE), triglycerides (TG) concentrations. Wheat gluten group had a higher fecal lipids, total cholesterol (TC) and bile acids (BA) than that of casein group (p < 0.05). Moreover, wheat gluten significantly increased total short-chain fatty acids (SCFA) concentrations in feces. Sequencing of 16S rRNA gene revealed that intake of wheat gluten decreased the relative abundances of Firmicutes and Erysipelotrichaceae, but to increased the relative abundances of Bateroidetes, Bacteroidales&#95;S24-7&#95;group and Ruminococcaceae. The lipid lowering properties of wheat gluten was associated with the lower ratio of Firmicutes/Bateroidetes, the lower of the bacterial taxa Erysipelotrichaceae and the higher of the bacterial taxa Bacteroidales&#95;S24-7&#95;group and Ruminococcaceae. These results suggest that wheat gluten modulate cholesterol metabolism by altering intestinal microflora.

Background and Aims: Non-Celiac Gluten Sensitivity (NCGS) is a recently proposed clinical condition causing both intestinal and extra-intestinal symptoms, without gastrointestinal lesions, which improve on avoiding gluten intake, in the absence of celiac disease and wheat allergy. The prevalence of this condition is still a matter of debate, in part due to the very recent introduction of an accepted diagnostic test, a double-blind, placebo controlled gluten challenge. However, this is a lengthy and cumbersome procedure, theoretically burdened by a significant reduction of patient compliance. ALCAT 5 is an automated in vitro test evaluating the toxic effect of gluten on neutrophils by the exposure of these cells to a gluten-containing extract of gluten-containing cereals. The test is very simple to perform, the results are rapidly obtained, and might represent, if sufficiently accurate, a promising alternative to diagnose gluten intolerance. The aim of this study was the comparison of ALCAT 5 results with those of a double-blind, placebo-controlled, gluten challenge, in a group of patients with clinically-suspected NCGS., Methods: Twenty-five patients (M/F 3/22, mean age 32 ± 4 yrs) with severe functional abdominal pain and bloating, who had previously undergone the ALCAT 5 test, were enrolled. All the subjects reported their symptoms on a gluten-containing diet and considered gluten the causal agent. Following the Salerno Experts' Criteria, they underwent a double-blind, placebo controlled trial with gluten vs placebo. A mean value during gluten ingestion >30% of the value during placebo was considered as indicative of gluten sensitivity., Results: After blinded administration of gluten, 13 out of 25 (52%) patients showed an increase in the severity of abdominal pain, and 11 out of 25 (44%) showed an increase in the severity of abdominal bloating. Considering these two symptoms together, in 16 patients out of 25 (64%), blinded gluten administration induced an increase of abdominal pain and/or bloating. The ALCAT 5 test proved to be positive in 20 and negative in 5 patients. In sixteen patients out of 25 the result of ALCAT 5 agreed with the double-blind trial (64%). In particular, both tests were positive in 14 patients and negative in 2., Conclusions: In this subgroup of patients, ALCAT 5 could be used to support the clinical suspicion of the presence of NCGS and to address these patients to a blinded gluten challenge., (Copyright © 2018 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)

The study was aimed to compare the satiating effect of various protein hydrolysates in rats and examine the underlying mechanism associated with the satiety hormones. Food intake and portal satiety hormone levels were measured in rats. Enteroendocrine cell-lines were employed to study the direct effect of protein hydrolysates on gut hormone secretions. The results showed that oral preload of wheat gluten hydrolysate (WGH) suppressed food intake greater and longer than other hydrolysates. The portal peptide-YY levels in WGH-treated rats at 2 h and 3 h were higher than those in control- and lactalbumin hydrolysate (LAH)-treated rats. In a distal enteroendocrine cell model, WGH more potently stimulated glucagon-like peptide-1 secretion than LAH, and the effect was largely enhanced by pepsin/pancreatin digestion of WGH. These results suggest WGH is potent in activating enteroendocrine cells to release satiety hormones leading to the prolonged suppression of food intake.

The thermo-active serine peptidase aqualysin 1 (Aq1) of Thermus aquaticus was applied in bread making to study the relative contribution of thermoset gluten to bread crumb texture. Aq1 is active between 30 °C and 90 °C with an optimum activity temperature of around 65 °C. It is inhibited by wheat endogenous serine peptidase inhibitors during dough mixing and fermentation and starts hydrolyzing gluten proteins during baking above 80 °C when the enzyme is no longer inhibited and most of the starch is gelatinized and contributes to structure formation. Aq1 activity reduced the molecular weight of gluten proteins and significantly increased their extractability in sodium dodecyl sulfate containing medium. While it had no impact on the specific bread volume and only limited impact on hardness, cohesiveness, springiness, resilience and chewiness, it impacted bread crumb coherence. We conclude that starch has a greater impact on crumb texture than thermoset gluten., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Gluten-related disorders (GRD) affect millions of people worldwide and have been related to the composition and metabolism of the gut microbiota. These disorders present differently in each patient and the only treatment available is a strict life-long gluten-free diet (GFD). Several studies have investigated the effect of a GFD on the gut microbiota of patients afflicted with GRD as well as healthy people. The purpose of this review is to persuade the biomedical community to think that, while useful, the results from the effect of GFD on health and the gut microbiota cannot be extrapolated from one population to others. This argument is primarily based on the highly individualized pattern of gut microbial composition and metabolic activity in each person, the variability of the gut microbiota over time and the plethora of factors associated with this variation. In addition, there is wide variation in the composition, economic viability, and possible deleterious effects to health among different GFD, both within and among countries. Overall, this paper encourages the conception of more collaborative efforts to study local populations in an effort to reach biologically and medically useful conclusions that truly contribute to improve health in patients afflicted with GRD.

Objective: High- protein diets have become increasingly popular with various touted benefits. However, the extent to which protein quantity and source affects cognitive functioning through altering postprandial amino acid profiles has not been investigated. Further, whether all protein sources are similarly anorexigenic is uncertain. The objective of this study was to determine the influence of protein level and source on Barnes maze performance, satiety and plasma amino acid levels in male Sprague-Dawley rats., Methods: Rats were entrained to a meal-feeding schedule consisting of a 30 minutes meal, equivalent to 20% of average daily intake, one hour into the dark phase then ad libitum access to food for 5 h. On test days, rats received one of three isocaloric diets as their first meal, hereafter referred to as Egg White (EW), Wheat Gluten (WG), or Basal, and then were measured for cognitive performance, feeding behavior, or plasma amino acid levels via jugular catheter. Percentage energy from protein was 35% for both EW and WG and 20% for Basal with equal amounts provided by EW and WG proteins., Results: Rats provided EW performed similarly to Basal on the Barnes maze, whereas WG performed worse. EW increased satiety, whereas WG reduced satiety relative to Basal. Both EW and WG increased postprandial concentrations of large neutral and branched chain amino acids relative to Basal, but in EW, concentrations were slower to peak, and peaked to a higher level than WG., Discussion: Results demonstrate the importance of protein source for cognition and satiety enhancing effects of a high-protein meal.

Celiac disease (CD) is an immune-mediated enteropathy triggered by ingested gluten in genetically susceptible individuals and sustained by both adaptive and innate immune responses. Recent studies in murine macrophages demonstrated that the activation of arginase (ARG) metabolic pathway by gluten peptides contributes to the modulation of intestinal permeability in vitro. Here we characterize the effects of gluten on arginine metabolism and cell polarization in human monocytes from both healthy and CD subjects; both a simplified enzymatic digestion of gliadin and a physiological digestion of whole wheat have been tested. Results indicate that gluten digests induce the onset of an M2-like phenotype in activated macrophages; more precisely, both isoforms of arginase, ARG1 and ARG2, are induced likely due to the inhibition of mTOR and the consequent induction of C/EBPβ transcription factor. These effects are independent from the origin of gluten as well as from the digestive protocol employed; moreover, no statistical difference can be evidenced between healthy and CD patients, excluding a diverse predisposition of CD monocytes to gluten-triggered polarization with respect to healthy immune cells. Overall, the present findings sustain a role for arginase pathway in the immune response elicited by human monocytes toward ingested gluten that, hence, deserves particular attention when addressing the pathogenesis of CD., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The composition, structure, and proper positioning of amino acid in a peptide are closely related to its antioxidant activity. In this study, we purified antioxidant peptides from corn protein hydrolysates (CPH) and identified novel antioxidant peptides from fraction CPH2-III as Ala-Gly-Ile/Leu-Pro-Met (AGI/LPM; 487.62Da) and His-Ala-Ile/Leu-Gly-Ala (HAI/LGA; 467.53Da). AGLPM and HALGA exhibited better oxygen radical absorbance capacities than AGIPM and HAIGA did (P<0.05), as assessed using HepG2 cells with the cellular antioxidant activity assay (CAA) and electron spin resonance (ESR) spectroscopy. Finally, the secondary structure was determined using circular dichroism (CD). ESR showed that the AGLPM and HALGA peptides had the strongest abilities to scavenge hydroxyl radicals, by 79.41±1.41% and 75.16±2.26%, respectively. Thus, corn gluten meal could be used as a potential source of antioxidant peptides for food applications. Additionally, the amino acid Leu compared with Ile may be a critical factor contributing to strong antioxidant activity than the Ile in the peptide sequence (not C-terminus or N-terminus) and CD showed that the lower α-helix and random coil are the main causes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The degree of hydrolysis (DH), peptide content and angiotensin I-converting enzyme (ACE) inhibitory activity of hydrolysates are the three most important indexes for process control in proteins enzymatic hydrolysis and ACE inhibitory peptides preparation. In this study, a miniature fiber optical spectrometer in conjunction with multivariate analysis for in-situ and real-time monitoring of the parameters (DH, peptide content and ACE inhibitory activity) in wheat gluten (WG) hydrolysis process. Synergy interval partial least square (Si-PLS) algorithm was performed to variables selection and the regression model was calibrated. The performance of a model was evaluated by the correlation coefficient (R p ) and the root mean square error (RMSEP) in the prediction set. The results showed that R p =0.9270, RMSEP=1.73% for DH; R p =0.9673, RMSEP=0.79mg/ml for peptide content; R p =0.9507, RMSEP=5.12% for ACE inhibitory. This work demonstrated that miniature fiber optical spectrometer combined Si-PLS model can be used as an alternative method for in-situ and real-time monitoring the enzymatic process of WG., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background & Aims: Celiac disease is a chronic small intestinal inflammatory disorder mediated by an immune response to gluten peptides in genetically susceptible individuals. Celiac disease is often diagnosed in early childhood, but some patients receive a diagnosis late in life. It is uncertain whether pediatric celiac disease is distinct from adult celiac disease. It has been proposed that gluten-reactive T cells in children recognize deamidated and native gluten epitopes, whereas T cells from adults only recognize deamidated gluten peptides. We studied the repertoire of gluten epitopes recognized by T cells from children and adults., Methods: We examined T-cell responses against gluten by generating T-cell lines and T-cell clones from intestinal biopsies of adults and children and tested proliferative response to various gluten peptides. We analyzed T cells from 14 children (2-5 years old) at high risk for celiac disease who were followed for celiac disease development. We also analyzed T cells from 6 adults (26-55 years old) with untreated celiac disease. All children and adults were positive for HLA-DQ2.5. Biopsies were incubated with gluten digested with chymotrypsin (modified or unmodified by the enzyme transglutaminase 2) or the peptic-tryptic digest of gliadin (in native and deamidated forms) before T-cell collection., Results: Levels of T-cell responses were higher to deamidated gluten than to native gluten in children and adults. T cells from children and adults each reacted to multiple gluten epitopes. Several T-cell clones were cross-reactive, especially clones that recognized epitopes from γ-and ω-gliadin. About half of the generated T-cell clones from children and adults reacted to unknown epitopes., Conclusions: T-cell responses to different gluten peptides appear to be similar between adults and children at the time of diagnosis of celiac disease., (Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Gluten is the only known environmental factor that triggers celiac disease. Several studies have described an imbalance between the intestinal microbiota of different individuals based on diagnoses. Moreover, recent studies have suggested that human bacteria may play an important role in gluten hydrolysis. However, there has been no research focusing on the small intestine. This study aimed to characterize the adult small intestine microbiota possibly implicated in gluten hydrolysis. Duodenal biopsies from different diagnosed individuals were cultured in a gluten-containing medium, and the grown microbiota was analyzed by culture dependent/independent methods. Results showed that gluten-degrading bacteria can be found in the human small intestine. Indeed, 114 bacterial strains belonging to 32 species were isolated; 85 strains were able to grow in a medium containing gluten as the sole nitrogen source, 31 strains showed extracellular proteolytic activity against gluten protein and 27 strains showed peptidolytic activity towards the 33 mer peptide, an immunogenic peptide for celiac disease patients. We found that there are no differences based on the diagnosis, but each individual has its own population of gluten-hydrolyzing bacteria. These bacteria or their gluten-degrading enzymes could help to improve the quality of life of celiac disease patients'., (Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Background: We previously found that the introduction of small quantities of gluten at 4-6 mo of age did not reduce the risk of celiac disease (CD) in a group of high-risk children. However, the consumption of high amounts of gluten early in life has been suggested to increase CD risk. Objective: The aim of this study was to evaluate this hypothesis by using data from the previous study of the PreventCD trial (www.preventcd.com). Design: Gluten intake was prospectively quantified by using specific food records between 11 and 36 mo of age in 715 children positive for the human leukocyte antigen ( HLA )- DQ2 and/or HLA -DQ8 from 5 European countries. According to the PreventCD protocol, infants received 100 mg immunologically active gluten/d or placebo from 4 to 6 mo of age, with a stepwise and fixed gluten increase until age 10 mo and unrestricted intake thereafter. The primary outcome of the present study was the impact of the amount of gluten consumed from age 10 mo onward on CD development. Results: Mean daily gluten intakes from 10 mo onward were significantly different between countries for children at all ages ( P < 0.001) but not between children who developed CD and those who did not within the same country ( P > 0.05). The variables country, sex, intervention group, and gluten consumption pattern did not show significant associations with CD development risk (HRs not significant). In addition, the interaction between HLA risk group and gluten consumption pattern showed no significant risk on CD development, except for the DQ2.2/DQ7 haplotype (HR: 5.81; 95% CI: 1.18, 28.74; P = 0.031). Conclusions: Gluten consumption patterns as well as the amount of gluten consumed at 11-36 mo of age do not influence CD development for most related HLA genotypes in children with a genetic risk. This study reports the gluten consumption pattern in children at risk of CD from different European countries. This trial was registered at www.controlled-trials.com as ISRCTN74582487., (© 2017 American Society for Nutrition.)

Gluten-induced aggregation of K562 cells represents an in vitro model reproducing the early steps occurring in the small bowel of celiac patients exposed to gliadin. Despite the clear involvement of TG2 in the activation of the antigen-presenting cells, it is not yet clear in which compartment it occurs. Herein we study the calcium-dependent aggregation of these cells, using either cell-permeable or cell-impermeable TG2 inhibitors. Gluten induces efficient aggregation when calcium is absent in the extracellular environment, while TG2 inhibitors do not restore the full aggregating potential of gluten in the presence of calcium. These findings suggest that TG2 activity is not essential in the cellular aggregation mechanism. We demonstrate that gluten contacts the cells and provokes their aggregation through a mechanism involving the A-gliadin peptide 31-43. This peptide also activates the cell surface associated extracellular TG2 in the absence of calcium. Using a bioinformatics approach, we identify the possible docking sites of this peptide on the open and closed TG2 structures. Peptide docks with the closed TG2 structure near to the GTP/GDP site, by establishing molecular interactions with the same amino acids involved in stabilization of GTP binding. We suggest that it may occur through the displacement of GTP, switching the TG2 structure from the closed to the active open conformation. Furthermore, docking analysis shows peptide binding with the β-sandwich domain of the closed TG2 structure, suggesting that this region could be responsible for the different aggregating effects of gluten shown in the presence or absence of calcium. We deduce from these data a possible mechanism of action by which gluten makes contact with the cell surface, which could have possible implications in the celiac disease onset.

Vegan protein-based diet has attracted increasing interest in the prevention of metabolic syndrome (MetS). Meanwhile, adiponectin has become a highly potential molecular target in the prevention of MetS. Our study will identify a potential vegan protein diet for the prevention of MetS using rat models. Thirty-six Wistar rats were randomly assigned into three groups and given diets containing one of the following proteins for 12 weeks: casein (CAS, control diet), soy protein (SOY), and gluten-soy mixed protein (GSM). Changes in metabolic parameters as well as the expressions of adiponectin and its receptors were identified. Compared to CAS diet, both SOY and GSM diets led to decreases in blood total cholesterol and triglycerides, but only GSM diet led to an increase in HDL-cholesterol; no marked difference was observed in blood glucose in all three groups; HOMA-IR was found lower only in SOY group. Among groups, the order of serum adiponectin level was found as GSM > SOY > CAS. Similar order pattern was also observed in expression of adiponectin in adipose tissue and AdipoR1 mRNA in skeletal muscle. Our results suggested for the first time that, besides SOY diet, GSM diet could also be a possible substitute of animal protein to prevent MetS., Competing Interests: The authors declare no conflict of interest.

Cereal proteins are of clinical interest because of their cytotoxic and immunogenic features being associated to allergic processes and intestinal disorders. In addition to gliadins, there has been suggested an important role for non-gluten modulating factors (nGMF) on the onset of intestinal inflammatory processes. In this study, the amino acid sequences generated after a simulated human gastrointestinal (sGI) digestion of a commercial extract of gliadins (GEF) and the nGMF-enriched fraction (nGEF) obtained from them were characterized (nanoESI-qQTOF). These fractions were fed (20 days) to Wistar rats, sensitized with interferon (IFN)-γ (1000 IU/rat) and further treated with indomethacin (2 mg/kg). The production of inflammatory mediators (ELISAs) and the expression (rt-qPCR) of innate biomarkers was monitored in duodenal tissue sections. There were also evaluated changes in defined leukocyte (flow cytometry) populations quantified in peripheral blood samples. Expected nGMF components, CM3 and 0.19, as well as toxic gliadin-derived peptides were generated after sGI digestion. Rats fed with the nGEF showed higher concentrations of IFNγ, as well as expression levels of TLR-4 and the peroxisome proliferator activated receptor-α in duodenal samples than those animals fed with GEF. Rats fed with GEF showed higher expression levels of the endocannabinoid receptor-1 and an increased CD4(+)CD3(+)Foxp3(+) cell population. The data points out significant different cytotoxic and immunogenic potential of the nGEF when administered independently of the GEF to which are commonly associated. However, proinflammatory responses to nGMF are masked when present associated to gliadins., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Gluten is a crucial functional component of bread, but the effect of increasing gluten content on gastrointestinal (GI) function remains uncertain. Our aim was to investigate the effect of increasing gluten content on GI function and symptoms in healthy participants using the unique capabilities of MRI. A total of twelve healthy participants completed this randomised, mechanistic, open-label, three-way crossover study. On days 1 and 2 they consumed either gluten-free bread (GFB), or normal gluten content bread (NGCB) or added gluten content bread (AGCB). The same bread was consumed on day 3, and MRI scans were performed every 60 min from fasting baseline up to 360 min after eating. The appearance of the gastric chime in the images was assessed using a visual heterogeneity score. Gastric volumes, the small bowel water content (SBWC), colonic volumes and colonic gas content and GI symptoms were measured. Fasting transverse colonic volume after the 2-d preload was significantly higher after GFB compared with NGCB and AGCB with a dose-dependent response (289 (SEM 96) v. 212 (SEM 74) v. 179 (SEM 87) ml, respectively; P=0·02). The intragastric chyme heterogeneity score was higher for the bread with increased gluten (AGCB 6 (interquartile range (IQR) 0·5) compared with GFB 3 (IQR 0·5); P=0·003). However, gastric half-emptying time was not different between breads nor were study day GI symptoms, postprandial SBWC, colonic volume and gas content. This MRI study showed novel mechanistic insights in the GI responses to different breads, which are poorly understood notwithstanding the importance of this staple food.

This study first investigated the effects of corn gluten hydrolysate (CGH) (1.5 g/day) administration for 7 days on appetite-responsive genes in lean Sprague-Dawley (SD) rats. In a second set of experiments, the metabolic changes occurring at multiple time points over 8 weeks in response to CGH (35.33% wt/wt) were observed in high-fat (HF, 60% of energy as fat) diet-fed SD rats. In lean rats, the hypothalamus neuropeptide-Y and proopiomelanocortin mRNA levels of the CGH group were significantly changed in response to CGH administration. In the second part of the study, CGH treatment was found to reduce body weight and perirenal and epididymal fat weight. CGH also prevented an increase in food intake at 2 weeks and lowered plasma leptin and insulin levels in comparison with the HF group. This reduction in the plasma and hepatic lipid levels was followed by improved insulin resistance, and the beneficial metabolic effects of CGH were also partly related to increases in plasma adiponectin levels. The Homeostasis Model of Assessment - Insulin Resistance (HOMA-IR), an index of insulin resistance, was markedly improved in the HF-CGH group compared with the HF group at 6 weeks. According to the microarray results, adipose tissue mRNA expression related to G-protein coupled receptor protein signaling pathway and sensory perception was significantly improved after 8 weeks of CGH administration. In conclusion, the present findings suggest that dietary CGH may be effective for improving hyperglycemia, dyslipidemia and insulin resistance in diet-induced obese rats as well as appetite control in lean rats.

The aim of this study is to determine the effect of proteins from cereals and legumes on heme iron (Fe) absorption. The absorption of heme Fe without its native globin was measured. Thirty adult females participated in two experimental studies (15 per study). Study I focused on the effects of cereal proteins (zein, gliadin and glutelin) and study II on the effects of legume proteins (soy, pea and lentil) on heme Fe absorption. When heme was given alone (as a control), study I and II yielded 6.2% and 11.0% heme absorption (p > 0.05). In study I, heme Fe absorption was 7.2%, 7.5% and 5.9% when zein, gliadin and glutelin were added, respectively. From this, it was concluded that cereal proteins did not affect heme Fe absorption. In study II, heme Fe absorption was 7.3%, 8.1% and 9.1% with the addition of soy, pea and lentil proteins, respectively. Only soy proteins decreased heme Fe absorption (p < 0.05). These results suggest that with the exception of soy proteins, which decreased absorption, proteins derived from cereals and legumes do not affect heme Fe absorption.

The objective of this study was to evaluate the efficacy of protecting PUFA within ground flaxseed against ruminal biohydrogenation by encapsulating them in a matrix consisting of a 1:1 blend of ground flaxseed and dolomitic lime hydrate (L-Flaxseed). Crossbreed heifers ( = 462, 346 ± 19 kg) were blocked by weight and randomly assigned to pens. Pens were assigned to 1 of 6 dietary treatments in a randomized complete block design. Treatment 1 consisted of a combination of 54.6% steam-flaked corn (SFC), 30.0% wet corn gluten feed, 8.0% roughage, and supplement (0% flaxseed). In treatments 2 and 3, a proportion of SFC was replaced with 3 and 6% flaxseed, respectively; in treatments 4, 5, and 6, SFC was replaced with 2, 4, or 6% L-Flaxseed, respectively. Cattle were fed for 140 or 168 d and then harvested in a commercial abattoir where carcass data were collected. Approximately 24 h after harvest, carcasses were evaluated for 12th-rib fat thickness, KPH, LM area, marbling score, and USDA yield and quality grades. Samples of LM were also obtained for determination of long-chain fatty acid profiles. Cattle that were fed diets with 4 and 6% L-Flaxseed consumed less feed than other treatments ( < 0.05), which adversely affected ADG. Compared with cattle fed 0% flaxseed, cattle in these treatments had lower final BW (18 and 45 kg less for the 4 and 6% L-Flaxseed treatments, respectively), less ADG (0.16 and 0.48 kg/day less for the 4 and 6% L-Flaxseed treatments, respectively), and lower carcass weights, dressing percentages, LM areas, backfat thicknesses, and marbling scores ( < 0.05). The addition of flaxseed or 2% L-Flaxseed did not affect performance or carcass traits ( > 0.05). Supplementation with flaxseed increased ( < 0.05) the concentration of α-linolenic acid (ALA) in meat (0.173, 0.482, 0.743 mg/g for 0, 3, and 6% flaxseed, respectively). Furthermore, proportionate increases in the ALA content of muscle tissue were 47% greater when flaxseed was encapsulated within the dolomitic lime hydrate matrix (0.288, 0.433, 0.592 mg/g for 2, 4, and 6% L-Flaxseed, respectively). Both products showed a linear response in ALA concentration ( > 99%; increases for Flaxseed and L-Flaxseed of 0.095 and 0.140 mg of ALA/g of tissue for each percentage of flaxseed added). This study indicates that a matrix consisting of dolomitic lime hydrate is an effective barrier to ruminal biohydrogenation of PUFA; however, adverse effects on DMI limit the amounts that can be fed.

Objectives: Studies have suggested a link between diet and behavior in children with autism spectrum disorders (ASDs). Parental reports of behavioral changes upon exposure to gluten and/or casein are common in clinical practice. An association between diet type, intestinal permeability (IP) ('leaky gut'), and behavior has been long proposed but not substantiated. We explored this possible association in this trial., Methods: This randomized double-blind, placebo-controlled study explored the effects of gluten and milk on IP and behavior in children with ASDs over a period of 4 weeks. IP assessed by lactulose:mannitol (L/M) sugar permeability test and behavior assessed by the Aberrant Behavior Checklist and Conners Parent Rating were measured. Gastrointestinal symptoms in both groups were also monitored., Results: Neither the L/M ratio nor behavioral scores were different between groups exposed to gluten/dairy or placebo. The changes observed were noted to be small and not clinically significant., Discussion: Our study although underpowered to show small differences does not support an association between dietary gluten/milk, IP, and behavioral changes in subjects with ASD.

Background: Leptin resistance is considered a primary risk factor for obesity. It has been hypothesized that dietary cereal grain protein could cause leptin resistance by preventing leptin from binding to its receptor. Non-degraded dietary wheat protein has been found in human serum at a mean level of 41 ng/mL. Here, we report our findings from testing whether enzymatically digested gluten from wheat prevents leptin from binding to the leptin receptor in vitro. Gluten from wheat was digested with pepsin and trypsin under physiological conditions. Pepsin and trypsin activity was removed from the gluten digest with a 10 kDa spin-filter or by heat treatment at 100°C for 30 min. Binding to the leptin receptor of leptin mixed with gluten digest at a series of concentrations was measured using surface plasmon resonance technology., Results: Binding of the gluten digest to the leptin receptor was not detected. Spin-filtered gluten digest inhibited binding of leptin to the leptin receptor, with 50% inhibition at a gluten digest concentration of ~10 ng/mL. Heat-treated gluten digest did not inhibit leptin binding., Conclusions: Digested wheat gluten inhibits binding of leptin to the leptin receptor, with half-maximal inhibition at 10 ng/mL. The inhibition is significant at clinically relevant concentrations and could therefore serve as a novel pathway to investigate to understand the molecular basis of leptin resistance, obesity and associated disorders.

Results of our earlier studies showed the ability of ciliates Eudiplodinium maggii to digest and metabolize commercial chitin. The natural source of this polysaccharide in the rumen are fungi. The objectives of present research were to determine the effect of fungal zoospores on the survival and population density of E. maggii to quantify the concentration of chitin in the cells of protozoa and to examine the ability of E. maggii, to ferment chitin of fungal zoospores. The cultivation experiment showed that the survival of protozoa was shorter than 4 days when the culture medium was composed of buffer solution and lyophilized fungal spores. An enrichment of this medium with wheat gluten prolonged the survival of ciliates up to 8 days. The supplementation of the last medium with meadow hay enabled the protozoa to survive for 28 days but a positive effect was observed only during the last 8 days of experiment. The chitin content was 0.27 ng and 0.21-0.35 ng per single zoospore and ciliate, respectively. An increase in the concentration of volatile fatty acids (VFA) was found when protozoa were incubated with zoospores. The production rate of VFA was 46.3 pM/protozoan per h whereas the endogenous production did not exceed 31 pM/protozoan per h. The molar proportion of acetic acid was 77.7% and these of butyric and propionic acids-12.2 and 11.0%, respectively. The obtained results make it evident that carbohydrates present in fungal zoospores were utilized by protozoa in energy yielding processes., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The aim of this study was to test the hypothesis that a combination of corn gluten hydrolysate (CGH) and capsaicin may have an additive or synergistic effect on body weight reduction. For 13 weeks, male Sprague-Dawley rats were provided a diet to induce obesity. Afterward, the rats were randomly divided into 5 dietary groups: the normal control (n = 5), the high-fat control (n = 8), the high-fat diet (HFD) containing 35% CGH (n = 7), the HFD containing 0.02% capsaicin (HF-P) (n = 8), and the HFD containing both CGH and capsaicin (HF-CP) (n = 7) for an additional 4 weeks. Administration of CGH plus capsaicin, along with a HFD, led to significant decreases in body weight, fat mass, lipids in the liver, and plasma leptin as well as increases in plasma adiponectin. The pattern of gene expression was different in each target organ. In the liver, up-regulation of peroxisome proliferator-activated receptor α, carnitine palmitoyltransferase 1α, and acyl-coenzyme A oxidase was found in the HF-CP group. In contrast, down-regulation of peroxisome proliferator-activated receptor γ was found in both the HFD containing 35% CGH and HF-CP groups. In skeletal muscle, up-regulation of insulin receptor and uncoupling protein 3 was found in the HF-P group only, whereas up-regulation of the glucose transporter 4 gene was observed in both the HF-CP and HF-P groups. In adipose tissue, up-regulation of peroxisome proliferator-activated receptor γ and hormone-sensitive lipase was only found in the HF-CP group. In summary, this study suggests that CGH and capsaicin perform complementary actions on food intake, lipid metabolism, and insulin sensitivity by a coordinated control of energy metabolism in the liver, adipose tissue, and skeletal muscle, thus exerting an additive effect on body weight reduction., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Previous studies have showed that wheat gluten hydrolysate (WGH) has the anti-oxidative property. In the present study, we examined the possible safety property of WGH and the beneficial effects of WGH to extend lifespan and induce stress resistance using nematode Caenorhabditis elegans as the in vivo assay system. We found that WGH at concentrations of 0.1-1 mg/mL did not cause lethality, influence development, alter locomotion behavior and brood size, and induce significant intestinal autofluorescence and reactive oxygen species (ROS) production in young adults. Treatment with 0.1-1 mg/mL of WGH significantly extended lifespans of nematodes under the normal conditions. Moreover, WGH treatment significantly inhibited the induction of intestinal autofluorescence and suppressed the decrease in locomotion behavior during the aging process of nematodes. Furthermore, pre-treatment with 1 mg/mL of WGH significantly suppressed the adverse effects caused by heat-stress or oxidative stress on nematodes as indicated by the alterations of both lifespan and intestinal ROS production. Therefore, WGH treatment is relatively safe and has beneficial effects on nematodes under both the normal conditions and the stress conditions.

Background: Patients with persistent symptoms and/or villous atrophy despite strict adherence to a gluten-free diet (GFD) have non-responsive celiac disease (NRCD). A subset of these patients has refractory celiac disease (RCD), yet some NRCD patients may simply be reacting to gluten cross-contamination. Here we describe the effects of a 3-6 month diet of whole, unprocessed foods, termed the Gluten Contamination Elimination Diet (GCED), on NRCD. We aim to demonstrate that this diet reclassifies the majority of patients thought to have RCD type 1 (RCD1)., Methods: We reviewed the records of all GFD-adherent NRCD patients cared for in our celiac center from 2005-2011 who were documented to have started the GCED. Response to the GCED was defined as being asymptomatic after the diet, with normal villous architecture on repeat biopsy, if performed., Results: Prior to the GCED, all patients were interviewed by an experienced dietitian and no sources of hidden gluten ingestion were identified. 17 patients completed the GCED; 15 were female (88%). Median age at start of the GCED was 42 years (range 6-73). Fourteen patients (82%) responded to the GCED. Six patients met criteria for RCD prior to the GCED; 5 (83%) were asymptomatic after the GCED and no longer meet RCD criteria. Of the 14 patients who responded to the GCED, 11 (79%) successfully returned to a traditional GFD without resurgence of symptoms., Conclusions: The GCED may be an effective therapeutic option for GFD-adherent NRCD patients. Response to this diet identifies a subgroup of patients, previously classified as RCD1, that is not truly refractory to dietary treatment. Preventing an inaccurate diagnosis of RCD1 avoids immunotherapy. Most patients are able to return to a traditional GFD without return of symptoms.

Corn gluten feed and dried distillers grains plus solubles (DDGS) were evaluated as replacements for soybean meal and ground ear corn when supplemented with corn silage during 2 yr of a beef cattle stockering program. Experiment 1: In YR 1, 104 steers (initial BW = 305 ± 30 kg), and in YR 2, 56 steers and 38 heifers (initial BW = 301 ± 32 kg) were stratified by weight and assigned to 1 of 9 groups. Each group was randomly assigned to 1 of 3 corn silage-based (75% of DM) diets supplemented with: i) corn gluten feed (CGF), ii) DDGS, or iii) soybean meal and ground ear corn (CSBM) at 25% of DM. On d 0, 28, 56, and 84, BW and BCS were recorded. Additionally, ribeye area, 12th rib fat thickness, intramuscular fat, and rump fat thickness were assessed via ultrasound on 9 (YR1) and 4 (YR 2) steers per pen that were randomly assigned as observational units. Average daily gain was greater (P < 0.05) for steers fed DDGS and CSBM compared with CGF (1.08, 1.08, and 0.94 kg/d, respectively). Average DMI (P < 0.05) was less for DDGS compared with CSBM with CGF intermediate (18.1, 18.8, 20.2 g/kg BW, respectively), and the resulting G:F was greatest for DDGS (P = 0.01). Cost per kilogram of BW gain was least for DDGS (P > 0.05). Ultrasound data indicated no differences (P ≥ 0.13) in predicted carcass traits among treatments. Experiment 2: Diets from Exp. 1 were subjected to in vitro digestion for incubation times of 0, 2, 4, 8, 16, 24, 48, and 72 h to estimate DM degradation, gas production kinetics, and CP fractions. The potentially degradable DM fraction was greater (P = 0.01) for CSBM compared with CGF and DDG. Total gas production and rate of gas production was not different among treatments (P > 0.42). Rumen degradable protein was greatest for CSBM and least for DDG (P = 0.001). These data indicate that DDGS can be used to replace soybean meal and corn in silage-based stocker systems to decrease feed costs without compromising animal performance and CGF may decrease animal performance.

Several studies have documented that dietary modifications influence the development of type 1 diabetes. However, little is known about the interplay of dietary components and the penetration of diabetes incidence. In this study we tested if wheat gluten is able to induce differences in the cytokine pattern of Foxp3(+) regulatory T cells, as well as Foxp3(-) T cells, isolated from intestinal mucosal lymphoid tissue and non-mucosal lymphoid compartments in BALB/c mice. The gluten-containing standard diet markedly changed the cytokine expression within Foxp3(-) T cells, in all lymphoid organs tested, towards a higher expression of pro-inflammatory interferon-γ (IFN-γ), interleukin-17 (IL-17) and IL-2. In Foxp3(+) regulatory T cells, gluten ingestion resulted in a mucosal increase in IL-17 and IL-2 and an overall increase in IFN-γ and IL-4. The gluten-free diet induced an anti-inflammatory cytokine profile with higher proportion of transforming growth factor-β (TGF-β)(+) Foxp3(-) T cells in all tested lymphoid tissues and higher IL-10 expression within non-T cells in spleen, and a tendency towards a mucosal increase in TGF-β(+) Foxp3(+) regulatory T cells. Our data shows that the gluten-containing standard diet modifies the cytokine pattern of both Foxp3(-) T cells and Foxp3(+) regulatory T cells towards a more inflammatory cytokine profile. This immune profile may contribute to the higher type 1 diabetes incidence associated with gluten intake., (© 2012 Blackwell Publishing Ltd.)

Wet corn gluten feed (WCGF), a byproduct of the wet-milling industry, is commonly substituted in lactating dairy rations for both forages and concentrates. Previous research has shown that increasing WCGF in the diet decreased ruminal pH, likely due in part to decreasing particle size as forage inclusion rate decreased. The objective of this study was to maintain at least 10% of ration particles >19 mm in length across diets while increasing WCGF inclusion in the diet. We hypothesized that as WCGF increased in this scenario, dry matter intake (DMI) and milk yield would increase and ruminal pH would be maintained. Seven ruminally cannulated, lactating Holstein cows (4 multiparous and 3 primiparous) were used in an incomplete 4×4 Latin square design. Treatments included 0, 12.4, 24.5, or 35.1% WCGF and used alfalfa hay to maintain particle size. Across treatments, crude protein and neutral detergent fiber concentrations were held relatively constant. Four 21-d periods were used with 17d of adaptation and 4d of sample collection. Indwelling ruminal pH probes were used during sampling periods and recorded pH every 5 min. Particle size of total mixed rations and orts were analyzed using a Penn State Particle Separator (The Pennsylvania State University, University Park). Results were analyzed with mixed models to test the fixed effect of treatment. All diets contained ≥10% of particles >19 mm; however, as WCGF increased, the proportion of particles >19 mm decreased. Interestingly, with increasing WCGF, cows sorted for the particles >19 mm but against particles on the bottom screen and pan. With increasing WCGF, ruminal pH was not affected, but DMI and milk yield increased in a quadratic fashion, with the peak responses for the 24.5% WCGF diet. Milk protein, lactose, and fat concentrations were not affected by treatment; however, milk protein and lactose yields increased with the inclusion of WCGF because of the increased milk yield. Production efficiency was not affected by treatments. Thus, if adequate particle size is maintained when WCGF increases in the diet, DMI and milk yield increase while maintaining production efficiency and ruminal pH., (Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The objectives of this study were to determine the chemical composition, energy content and amino acid digestibility for corn gluten meals (CGM) and to develop prediction equations for estimating energy content and amino acid digestibility for growing pigs based on the chemical characteristics of these meals. The 15 CGM tested were obtained from seven Chinese companies. Experiment 1 was conducted to determine the digestible (DE) and metabolisable energy (ME) of the 15 CGM. The 18 growing barrows (38 +/- 4 kg) were assigned to three 6 x 6 Latin square designs. The 15 CGM test diets were formulated to contain 19.20% CGM, which replaced 20% of the energy supplied by corn and crystalline amino acid in the basal diet. Experiment 2 was conducted to determine the apparent (AID) and standardised (SID) ileal digestibility of the crude protein (CP) and amino acids in the 15 CGM using chromic oxide as an inert marker. The 18 growing barrows (25 +/- 2 kg) fitted with a simple T-cannula were assigned to three 6 x 6 Latin square designs. The 15 test diets contained 35% of one of the 15 CGM as the sole source of amino acids in the diet. The results showed a considerable variation in the chemical composition of CGM within and among plants. On dry matter basis, the DE and ME content of the CGM ranged from 18.8 to 21.0 MJ/kg and from 18.0 to 19.9 MJ/kg, respectively. There were no significant differences in the AID and SID for CP, arginine, lysine, glycine and proline among the 15 CGM, however, for all the other amino acids, significant differences were found for their AID and SID. With R2 values exceeding 0.50, the DE of CGM can be predicted accurately from CP and fibre content and ME from starch and fibre content. Suitable prediction equations for SID of methionine were also developed.

Wheat gluten hydrolysate (WGH) was fractionated on the basis of the amphoteric nature of sample peptides by preparative isoelectric focusing (autofocusing). Cooked pork patties were stored at 4 and 20 °C in the dark. WGH and autofocusing fractions suppressed the oxidation of lipids in the patties. The acidic (pI < 3.0) and basic (pI > 9.0) autofocusing fractions suppressed lipid oxidation in the cooked patties to a greater extent than other fractions and WGH. Each autofocusing fraction was evaluated by 1,1-diphenyl-2-picrylhydrazyl and hydroxyl radical scavenging activities, β-carotene bleaching, oxygen radical absorbance capacity, and Fe(2+) chelating assays; however, none of the in vitro assays predicted the suppressive effect of WGH on lipid oxidation in the cooked patties. These findings suggest that the microdistribution of peptides in food systems and their interaction with food matrix compounds play a significant role in the suppression of lipid oxidation in meat patties rather than radical scavenging activity.

Productivity of lactating dairy cows fed diets with wet corn gluten feed (WCGF, Sweet Bran, Cargill Inc., Blair, NE) as the primary energy substrate and prairie hay as the primary source of physically effective neutral detergent fiber (peNDF) was assessed relative to a control diet. Forty-eight Holstein cows, 100 to 250 d in milk, were randomly assigned to 1 of 6 pens and pens were randomly assigned to treatment sequence in a replicated 3×3 Latin square. Treatments were a control diet with 18% alfalfa, 18% corn silage, 33% WCGF, and 15% forage NDF (CON); a diet with 20% tallgrass prairie hay, 46% WCGF, and 13% forage NDF (TPH20); and a diet with 14% tallgrass prairie hay, 56% WCGF, and 9% forage NDF (TPH14). Midway through period 2, TPH14 was discontinued due to the high prevalence of diarrhea among cows on that treatment. Data from period 2 for TPH14 pens were discarded, and the pens that had been assigned to TPH14 for period 3 were randomly assigned to the other 2 treatments. Pen-level data were analyzed using linear mixed models, including the random effects of period and pen and the fixed effect of treatment. For animal-level data, additional random effects were introduced to account for subsampling. No evidence for treatment effects was apparent on dry matter intake. Least squares mean milk yields were 36.2, 34.6, and 35.2 kg/d for CON, TPH20, and TPH14, respectively, and were not significantly different. Milk fat concentration was higher for CON and TPH20 than for TPH14, with means of 3.48, 3.41, and 2.82%, respectively. Fat yield was significantly greater for CON compared with TPH20 and TPH14. Milk urea nitrogen was greatest for TPH20 and TPH14 and least for CON, consistent with differences in dietary protein content. Efficiencies, expressed as energy-corrected milk divided by dry matter intake, were 1.47, 1.42, and 1.24 for CON, TPH20, and TPH14, respectively, and were not significantly different. These data indicate that TPH14 did not provide adequate peNDF to support normal rumen function in mid lactation dairy cows; instead, TPH20 may be a feasible diet for use on dairies where high-NDF grass hay and WCGF are available., (Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)