UNASSIGNED: Understanding intestinal permeability is paramount for elucidating gastrointestinal health and pathology. The size and nature of the molecule traversing the intestinal barrier offer crucial insights into various acute and chronic diseases, as well as the evolution of some conditions. This study aims to assess the urinary excretion kinetics of gluten immunogenic peptides (u-GIP), a unique class of dietary peptides detectable in urine, in volunteers under controlled dietary conditions. This evaluation should be compared to established probes like lactulose, a non-digestible disaccharide indicative of paracellular permeability, and mannitol, reflecting transcellular permeability.
UNASSIGNED: Fifteen participants underwent simultaneous ingestion of standardized doses of gluten (10 g), lactulose (10 g), and mannitol (1 g) under fasting conditions for at least 8 hours pre-ingestion and during 6 hours post-ingestion period. Urine samples were collected over specified time intervals. Excretion patterns were analyzed, and correlations between the lactulose-to-mannitol ratio (LMR) and u-GIP parameters were assessed.
UNASSIGNED: The majority of u-GIP were detected within the first 12 hours post-ingestion. Analysis of the variability in cumulative excretion across two sample collection ranges demonstrated that lactulose and u-GIP exhibited similar onset and excretion dynamics, although GIP reached its maximum peak earlier than either lactulose or mannitol. Additionally, a moderate correlation was observed between the LMR and u-GIP parameters within the longest urine collection interval, indicating potential shared characteristics among permeability pathways. These findings suggest that extending urine collection beyond 6 hours may enhance data reliability.
UNASSIGNED: This study sheds light on the temporal dynamics of u-GIP in comparison to lactulose and mannitol, established probes for assessing intestinal permeability. The resemblance between u-GIP and lactulose excretion patterns aligns with the anticipated paracellular permeability pathway. The capacity to detect antigenic food protein fragments in urine opens novel avenues for studying protein metabolism and monitoring pathologies related to the digestive and intestinal systems.

BACKGROUND: In mammals, amino acid metabolism has evolved to control immune responses. Tryptophan (Trp) is the rarest essential amino acid found in food and its metabolism has evolved to be a primary regulatory node in the control of immune responses. Celiac disease (CeD) is a developed immunological condition caused by gluten intolerance and is linked to chronic small intestine enteropathy in genetically predisposed individuals. Dendritic cells (DCs), serving as the bridge between innate and adaptive immunities, can influence immunological responses in CeD through phenotypic alterations.
OBJECTIVE: This review aims to highlight the connection between Trp metabolism and tolerogenic DCs, and the significance of this interaction in the pathogenesis of CeD.
RESULTS: It is been recognized that various DC subtypes contribute to the pathogenesis of CeD. Tolerogenic DCs, in particular, are instrumental in inducing immune tolerance, leading to T-reg differentiation that helps maintain intestinal immune tolerance against inflammatory responses in CeD patients and those with other autoimmune disorders. T-regs, a subset of T-cells, play a crucial role in maintaining intestinal immunological homeostasis by regulating the activities of other immune cells. Notably, Trp metabolism, essential for T-reg function, facilitates T-reg differentiation through microbiota-mediated degradation and the kynurenine pathway.
CONCLUSIONS: Therefore, alterations in Trp metabolism could potentially influence the immune response in CeD, affecting both the development of the disease and the persistence of symptoms despite adherence to a gluten-free diet.

Advanced glycation end products (AGEs), a heterogeneous compound existed in processed foods, are related to chronic diseases when they are accumulated excessively in human organs. Protein-bound Nε-(carboxymethyl) lysine (CML) as a typical AGE, is widely determined to evaluate AGEs level in foods and in vivo. This study investigated the intestinal absorption of three protein-bound CML originated from main food raw materials (soybean, wheat and peanut). After in vitro gastrointestinal digestion, the three protein-bound CML digests were ultrafiltered and divided into four fractions: less than 1 kDa, between 1 and 3 kDa, between 3 and 5 kDa, greater than 5 kDa. Caco-2 cell monolayer model was further used to evaluate the intestinal absorption of these components. Results showed that the absorption rates of soybean protein isolate (SPI)-, glutenin (Glu)-, peanut protein isolate (PPI)-bound CML were 30.18%, 31.57% and 29.5%, respectively. The absorption rates of components with MW less than 5 kDa accounted for 19.91% (SPI-bound CML), 22.59% (Glu-bound CML), 23.64% (PPI-bound CML), respectively, and these samples were absorbed by paracellular route, transcytosis route and active route via PepT-1. Taken together, these findings demonstrated that all three protein-bound CML digests with different MW can be absorbed in diverse absorption pathways by Caco-2 cell monolayer model. This research provided a theoretical basis for scientific evaluation of digestion and absorption of AGEs in food.

OBJECTIVE:  This study is aimed to compare the effects of nutrition which has been enriched with different amounts of gluten to gluten-free diets on weight gain, diabetogenic state, hematological, and biochemical parameters.
METHODS:  A total of 40 newly weaned male Wistar albino rats used in the study were randomized into 4 different groups based on the gluten rations they were given. Following 12 weeks of diet they were killed and intracardiac blood samples were collected. Groups were identified as group 1 (n = 10): control group; normal rat ration containing wheat, group 2 (n = 10): gluten-free diet, group 3 (n = 10): ration containing medium level of gluten (normal rat diet+6% vital gluten) and group 4 (n = 10): ration containing high level of gluten (normal rat diet+12% vital gluten).
RESULTS:  In groups 3 and 4, high-density lipoprotein was found to be higher than the other 2groups. However, when group 2 results were compared to the other groups; the highest T3, T4, creatinine and B12 levels and the lowest gluten-specific IgE level were observed. alanine aminotransferase and aspartate aminotransferase levels were found to be higher in group 1 compared to the other 3 groups. No statistically significant difference was detected between the groups in terms of other parameters.
CONCLUSIONS:  This study provides evidence that a gluten-containing diet does not cause weight gain, has no diabetogenic effect, and also does not adversely affect general health in relation to hematological, biochemical, and various endocrinological parameters.

Gastrointestinal disorders dysregulate the biochemical environment of the gastrointestinal tract by altering pH conditions during the gastric phase of digestion or by reducing the secretion of pancreatin during the intestinal part of the process. Ingested functional food could therefore lose some of its health-promoting potential apart from its nutritional value. In this work, we aimed to manufacture bread marked by decreased gluten content, using a commercial or laboratory sourdough, that could be appropriate for patients afflicted with wheat allergy, hypertension and pancreatic malfunctions. A reference sample (no sourdough) was prepared alongside wheat and wheat-rye bread samples-produced with either commercial or laboratory sourdough (L. plantarum BS, L. brevis 1269, L. sanfranciscensis 20663). We measured the QQQPP allergen content (ELISA) in bread extracts digested in vitro and determined how these extracted components affect the level of active angiotensin and alpha amylase (spectrophotometry). We then elucidated how these properties changed when physiological digestion conditions (pH and pancreatin activity) were disturbed to mimic gastric hyperacidity, hypochlorhydria or exocrine pancreatic insufficiency. The key finding was that every tested type of bread produced with laboratory sourdough exhibited pronounced angiotensin-converting enzyme inhibition. The effect was preserved even in dysregulated digestive conditions. The use of laboratory sourdough prevented an increase in allergenicity when pancreatin was restricted as opposed to the commercial sourdough, which surpassed the reference sample reading at 50% pancreatin. No statistically consistent link was reported when the inhibition of alpha amylase was assayed. In conclusion, functional bread manufactured with sourdough composed of L. plantarum BS, L. brevis 1269, and L. sanfranciscensis 20663 was shown to be potentially capable of contributing to the treatment against hypertension as evidenced by in vitro research. It was also moderately safer with regard to its allergenicity.

In our editorial, we want to comment on the article by Stefanolo et al titled \"Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet\". Celiac disease is an immune-mediated disorder triggered by dietary gluten in genetically predisposed individuals. Although avoiding gluten can permit patients to live symptom-free, ongoing voluntary or involuntary exposure to gluten is common and associated with persistent villous atrophy in small bowel mucosa. As villous atrophy predisposes patients to life threatening complications, such as osteoporotic fractures or malignancies, therapeutic adjuncts to gluten-free diet become important to improve patients\' quality of life and, if these adjuncts can be shown to improve villous atrophy, avoid complications. Oral administration of enzyme preparations, such as endopeptidases that digest gluten and mitigate its antigenicity to trigger inflammation, is one clinical strategy under investigation. The article is about the utility of one endopeptidase isolated from Aspergillus niger. We critique findings of this clinical trial and also summarize endopeptidase-based as well as other strategies and how they can complement gluten-free diet in the management of celiac disease.

GSHO 2096 is a near isogenic barley line with extremely high grain β-amylase activity, a desirable trait in the malting and brewing industry. High levels of grain β-amylase activity are caused by a surge in endosperm-specific β-amylase (Bmy1) gene expression during the early stages of grain development with high expression levels persisting throughout development. Origins of the high β-amylase activity trait are perplexing considering GSHO 2096 is not supposed to have grain β-amylase activity. GSHO 2096 is reported to be derived from a Bowman x Risø 1508 cross followed by recurrent backcrossing to Bowman (BC5). Risø 1508 carries a mutated form of the barley prolamin binding factor, which is responsible for Bmy1 expression during grain development. Thus, the pedigree of GSHO 2096 was explored to determine the potential origins of the high grain β-amylase trait. Genotyping using the barley 50k iSelect SNP array revealed Bowman and GSHO 2096 were very similar (95.4 %) and provided evidence that both Risø 56 and 1508 are in the pedigree. Risø mutants 56 and 1508 both have perturbed hordein gene expression leading to a discernable pattern using SDS-PAGE. GSHO 2096 and Risø 56 have the same hordein pattern whereas Bowman and Risø 1508 have unique patterns. RNAseq revealed that Hor2 (B-hordein) gene expression was completely downregulated making it unique as the only known line with Bmy1 expression without Hor2 co-expression. Regardless of pedigree, GSHO 2096 remains an extremely valuable high β-amylase activity line with potential utilization in breeding for malt quality.

BACKGROUND: The differential diagnosis between patients with celiac disease (CD) and non-celiac gluten sensitivity (NCGS) is difficult when a gluten-free diet (GFD) has been initiated before the diagnostic work-up. Isolated increases in TCRγδ+ and celiac lymphogram (increased TCRγδ+ plus decreased CD3-) may enable differential diagnosis in this challenging clinical setting. This study evaluated: (1) the accuracy of %TCRγδ+ and celiac lymphogram for diagnosing CD before and after GFD and for differentiation with NCGS; (2) TCRγδ+ kinetics at baseline and after starting GFD in both CD and NCGS.
METHODS: The inclusion criteria were patients with CD (n = 104), NCGS (n = 37), and healthy volunteers (n = 18). An intestinal biopsy for intraepithelial lymphogram by flow cytometry was performed at baseline and after GFD. The optimal cutoff for CD diagnostic accuracy was established by maximizing the Youden index and via logistic regression.
RESULTS: %TCRγδ+ showed better diagnostic accuracy than celiac lymphogram for identifying CD before and after GFD initiation. With a cutoff > 13.31, the accuracy for diagnosing CD in patients under GFD was 0.88 [0.80-0.93], whereas the accuracy for diagnosing NCGS (%TCRγδ+ ≤ 13.31) was 0.84 [0.76-0.89]. The percentage of TCRγδ+ cells showed differential kinetics between CD (baseline 22.7% [IQR, 16.4-33.6] vs. after GFD 26.4% [IQR, 17.8-36.8]; p = 0.026) and NCGS (baseline 9.4% [IQR, 4.1-14.6] vs. after GFD 6.4% [IQR, 3.2-11]; p = 0.022).
CONCLUSIONS: TCRγδ+ T cell assessment accurately diagnoses CD before and after a GFD. Increased TCRγδ+ was maintained in the long term after GFD in CD but not in NCGS. Altogether, this suggests the potential usefulness of this marker for the differential diagnosis of these two entities in patients on a GFD.

In vitro models of autoimmunity are constrained by an inability to culture affected epithelium alongside the complex tissue-resident immune microenvironment. Coeliac disease (CeD) is an autoimmune disease in which dietary gluten-derived peptides bind to the major histocompatibility complex (MHC) class II human leukocyte antigen molecules (HLA)-DQ2 or HLA-DQ8 to initiate immune-mediated duodenal mucosal injury1-4. Here, we generated air-liquid interface (ALI) duodenal organoids from intact fragments of endoscopic biopsies that preserve epithelium alongside native mesenchyme and tissue-resident immune cells as a unit without requiring reconstitution. The immune diversity of ALI organoids spanned T cells, B and plasma cells, natural killer (NK) cells and myeloid cells, with extensive T-cell and B-cell receptor repertoires. HLA-DQ2.5-restricted gluten peptides selectively instigated epithelial destruction in HLA-DQ2.5-expressing organoids derived from CeD patients, and this was antagonized by blocking MHC-II or NKG2C/D. Gluten epitopes stimulated a CeD organoid immune network response in lymphoid and myeloid subsets alongside anti-transglutaminase 2 (TG2) autoantibody production. Functional studies in CeD organoids revealed that interleukin-7 (IL-7) is a gluten-inducible pathogenic modulator that regulates CD8+ T-cell NKG2C/D expression and is necessary and sufficient for epithelial destruction. Furthermore, endogenous IL-7 was markedly upregulated in patient biopsies from active CeD compared with remission disease from gluten-free diets, predominantly in lamina propria mesenchyme. By preserving the epithelium alongside diverse immune populations, this human in vitro CeD model recapitulates gluten-dependent pathology, enables mechanistic investigation and establishes a proof of principle for the organoid modelling of autoimmunity.

This study aims to understand the molecular and supramolecular transformations of wheat endosperm biopolymers during bread-making, and their implications to fabricate self-standing films from stale white bread. A reduction in the Mw of amylopectin (51.8 × 106 vs 425.1 × 106 g/mol) and water extractable arabinoxylans WEAX (1.79 × 105 vs 7.63 × 105 g/mol), and a decrease in amylose length (245 vs 748 glucose units) was observed after bread-baking. The chain length distribution of amylopectin and the arabinose-to-xylose (A/X) ratio of WEAX remained unaffected during bread-making, suggesting that heat- or/and shear-induced chain scission is the mechanism responsible for molecular fragmentation. Bread-making also resulted in more insoluble cell wall residue, featured by water unextractable arabinoxylan of lower A/X and Mw, along with the formation of a gluten network. Flexible and transparent films with good light-blocking performance (<30 % transmittance) and DPPH-radical scavenging capacity (~8.5 %) were successfully developed from bread and flour. Bread films exhibited lower hygroscopicity, tensile strength (2.7 vs 8.5 MPa) and elastic modulus (67 vs 501 MPa) than flour films, while having a 6-fold higher elongation at break (10.0 vs 61.2 %). This study provides insights into the changes in wheat biopolymers during bread-making and sets a precedent for using stale bread as composite polymeric materials.