RESUMEN

We comprehensively evaluated the expression of therapeutically targetable immune checkpoint molecules involved in celiac disease (CD). We have focused on the alteration of the CD200/CD200R pathway and Elafin expression in celiac disease and discussed their roles in regulating the immune response. There are limited data related to the expression or function of these molecules in celiac disease. This finding could significantly contribute to the understanding of the clinical manifestation of CD. CD200, CD200R and Elafin distributions were determined by ELISA and immunohistochemistry analyses in serum and biopsies of CD patients. Analyses of Th1 and Th17 cytokines were determined. PCR amplification of a fragment of the PI3 gene was carried out using genomic DNA isolated from whole blood samples of the study subjects. Different aliquots of the PCR reaction product were subjected to RFLP analysis for SNP genotyping and detection. We characterized the expression and function of the CD200-CD200R axis and PI3 in celiac disease. A significantly higher level of soluble CD200 and CD200R and lower expression of PI3 in serum of CD patients was observed compared to healthy controls. Consistent with our results, CD200 expression is regulated by IFN-gamma. Interaction of CD200/CD200R leads to production of type-Th1 and -Th17 cytokines. Regarding the PI3 genotype, the CT genotype proportion SNP rs1733103 and the GG genotype SNP rs41282752 were predominant in CD patients. SNP rs1733103 showed a significant association between the SNP variables and CD. In celiac disease the immune checkpoint is compromised or dysregulated, which can contribute to inflammation and the autoimmunity process. The study of these checkpoint points will lead to the development of targeted therapies aimed at restoring immunological balance in CD. Specific coding regions of the PI3 gene-splice variants predispose the Elafin protein, both at the transcriptional and post-translational levels, to modify its expression and function, resulting in reduced differential functional protein levels in patients with active celiac disease.

Asunto(s)

Enfermedad Celíaca , Proteínas de Punto de Control Inmunitario , Humanos , Elafina , Enfermedad Celíaca/genética , Genotipo , Citocinas/genética

RESUMEN

Prolyl endopeptidases (PEP) from Sphingomonas capsulata (sc) and Myxococcus xanthus (mx) selectively degrade gluten peptides in vitro, offering a potential therapeutic strategy for celiac disease. However, the mechanisms governing the interaction of these enzymes with their substrates remain unclear. In this study, conventional molecular dynamics simulations with a microsecond timescale and targeted molecular dynamics simulations were performed to investigate the native states of mxPEP and scPEP enzymes, as well as their allosteric binding with a representative substrate, namely, Z-Ala-Pro-p-nitroanilide (pNA). The simulations reveal that the native scPEP is in an open state, while the native mxPEP is in a closed state. When pNA approaches a closed mxPEP, it binds to an allosteric pocket located at the first and second ß-sheet of the ß-propeller domain, inducing the opening of this enzyme. Neither enzyme is active in the open or partly-open states. Enzymatic activity is enabled only when the catalytic pocket in the closed state fully accommodates the substrates. The internal capacity of the catalytic pocket of PEP in the closed state determines the maximum size of the gluten peptides that the enzymes can catalyze. The present work provides essential molecular dynamics information for the redesign or engineering of PEP enzymes.

Asunto(s)

Enfermedad Celíaca , Prolil Oligopeptidasas , Humanos , Prolil Oligopeptidasas/metabolismo , Serina Endopeptidasas/química , Simulación de Dinámica Molecular , Glútenes/química , Péptidos/química

RESUMEN

It has been increasingly demonstrated over the past few years that some proteolytically resistant gluten peptides may directly affect intestinal cell structure and functions by modulating pro-inflammatory gene expression and oxidative stress. The relationship between oxidative cell damage and Celiac Disease (CD) is supported by several studies on human intestinal epithelial cell lines, such as the Caco-2 cell model, already shown to be particularly sensitive to the pro-oxidative and pro-apoptotic properties of gluten protein digests. Through providing valuable evidence concerning some of the pathophysiological mechanisms that may be at play in gluten-related disorders, most of these in vitro studies have been employing simplified digestion schemes and intestinal cell systems that do not fully resemble mature enterocytes in terms of their characteristic tight junctions, microvilli and membrane transporters. Herein the peptide profile and pro-oxidative effect of two different gastrointestinal gliadin digestions was thoroughly characterized and comprehensively compared: one following the complete INFOGEST workflow and a second one by-passing gastric processing, to assess the dependence of gliadin-triggered downstream cell effects on pepsin activity. In both matrices, gluten-derived immunogenic peptide sequences were identified by non-targeted LC-MS/MS. Altogether, this study provides first-hand data concerning the still unexplored peptide composition, gastric-dependence and immunogenicity of physiologically representative gliadin protein digests as well as foundational clues stressing the need for more complex and integrated in vitro cell systems when modelling and exploiting gluten-induced perturbations in the nucleophilic tone and inflammatory status of intestinal epithelial cells.

Asunto(s)

Gliadina , Glútenes , Humanos , Glútenes/química , Gliadina/química , Células CACO-2 , Cromatografía Liquida , Espectrometría de Masas en Tándem , Péptidos/química , Células Epiteliales/metabolismo

RESUMEN

Metallic nanoparticles (mNPs) are widely used as food additives and can interact with gliadin triggering an immune response, but evaluation of the effects on crypts, hypertrophic in celiac subjects, is still lacking. This study evaluated the effects of gold and silver mNPs in combination with gliadin on crypt-like cells (HIEC-6). Transmission electron microscopy (TEM) was used to evaluate gliadin-mNP aggregates in cells. Western blot and immunofluorescence analysis assessed autophagy-related molecule levels (p62, LC3, beclin-1, EGFR). Lysosome functionality was tested with acridine orange (AO) and Magic Red assays. TEM identified an increase in autophagic vacuoles after exposure to gliadin + mNPs, as also detected by significant increments in LC3-II and p62 expression. Immunofluorescence confirmed the presence of mature autophagosomes, showing LC3 and p62 colocalization, indicating an altered autophagic flux, further assessed with EGFR degradation, AO and Magic Red assays. The results showed a significant reduction in lysosomal enzyme activity and a modest reduction in acidity. Thus, gliadin + mNPs can block the autophagic flux inducing a lysosomal defect. The alteration of this pathway, essential for cell function, can lead to cell damage and death. The potential effects of this copresence in food should be further characterized to avoid a negative impact on celiac disease subjects.

Asunto(s)

Oro , Nanopartículas , Humanos , Glútenes , Plata , Gliadina , Autofagia , Naranja de Acridina , Receptores ErbB

RESUMEN

The impact of different degrees of hydrolysis (DHs) on fibrillation when trypsin mediates wheat gluten (WG) fibrillation has not been thoroughly investigated. This study discussed the differences in amyloid fibrils (AFs) formed from wheat gluten peptides (WGPs) at various DH values. The results from Thioflavin T (ThT) fluorescence analysis indicated that WGPs with DH6 were able to form the most AFs. Changes in Fourier Transform Infrared (FTIR) absorption spectra and secondary structure also suggested a higher degree of fibrillation in DH6 WGPs. Analysis of surface hydrophobicity and ζ-potential showed that DH6 AFs had the highest surface hydrophobicity and the most stable water solutions. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) images revealed the best overall morphology of DH6 AFs. These findings can offer valuable insights into the development of a standardized method for preparing wheat gluten amyloid fibrils.

Asunto(s)

Amiloide , Triticum , Hidrólisis , Tripsina , Arritmias Cardíacas , Glútenes

RESUMEN

Celiac disease (CD) is a human autoimmune disease triggered by toxic gluten peptides. Recently, oral enzyme therapy has been proposed to ameliorate the health condition of CD patients based on the concept of removing pepsin-insensitive gluten-derived pro-immunogenic peptides. A Burkholderia peptidase, Bga1903, with promising gluten-degrading activity was characterized previously. Here, we report the crystal structure of Bga1903, in which the core has a α/ß/α fold featured with a twisted six-stranded parallel ß-sheet sandwiched between two layers of α-helices. The mutations at the substrate-binding pocket that might enhance the peptidase's affinity toward tetrapeptide PQPQ were predicted by FoldX. Accordingly, four single-substitution mutants, G351A, E380L, S386F, and S387L, were created. The specificity constant (kcat/KM) of wild type toward chromogenic peptidyl substrates Z-HPK-pNA, Z-HPQ-pNA, Z-HPL-pNA, and Z-QPQ-pNA are 30.2, 7.9, 3.3, and 0.79 s-1·mM-1, respectively, indicating that the QPQ motif, which frequently occurs in pro-immunogenic peptides, is not favorable. Among the mutants, E380L loses the hydrolytic activity toward Z-HPK-pNA, suggesting a critical role of E380 in preferring a lysine residue at the P1 position. S387L shows a 17-fold increase in the specificity constant toward Z-QPQ-pNA and hydrolyzes the pro-immunogenic peptides more efficiently than the wild-type peptidase.

Asunto(s)

Burkholderia , Enfermedad Celíaca , Humanos , Glútenes/metabolismo , Péptido Hidrolasas , Burkholderia/metabolismo , Péptidos/química , Sitios de Unión

RESUMEN

The influences of three wheat gluten peptides (WGP-LL, WGP-LML, and WGP-LLL) on the osmotic stress tolerance and membrane lipid component in brewer's yeast were investigated. The results demonstrated that the growth and survival of yeast under osmotic stress were enhanced by WGP supplementation. The addition of WGP upregulated the expressions of OLE1 (encoded the delta-9 fatty acid desaturase) and ERG1 (encoded squalene epoxidase) genes under osmotic stress. At the same time, WGP addition enhanced palmitoleic acid (C16:1) content, unsaturated fatty acids/saturated fatty acids ratio, and the amount of ergosterol in yeast cells under osmotic stress. Furthermore, yeast cells in WGP-LL and WGP-LLL groups were more resistant to osmotic stress. WGP-LL and WGP-LLL addition caused 25.08% and 27.02% increase in membrane fluidity, 22.36% and 29.54% reduction in membrane permeability, 18.38% and 14.26% rise in membrane integrity in yeast cells, respectively. In addition, scanning electron microscopy analysis revealed that the addition of WGP was capable of maintaining yeast cell morphology and reducing cell membrane damage under osmotic stress. Thus, alteration of membrane lipid component by WGP was an effective approach for increasing the growth and survival of yeast cells under osmotic stress. KEY POINTS: •WGP addition enhanced cell growth and survival of yeast under osmotic stress. •WGP addition increased unsaturated fatty acids and ergosterol contents in yeast. •WGP supplementation improved membrane homeostasis in yeast at osmotic stress.

Asunto(s)

Saccharomyces cerevisiae , Triticum , Ergosterol/metabolismo , Ácidos Grasos Insaturados/metabolismo , Glútenes/metabolismo , Lípidos de la Membrana/metabolismo , Presión Osmótica , Péptidos/metabolismo , Saccharomyces cerevisiae/metabolismo , Triticum/metabolismo

RESUMEN

Celiac disease (CD) is a multisystem disease in which different organs may be affected. We investigate whether circulating innate lymphoid cells (ILCs) contribute to the CD peripheral inflammatory status. We find that the CD cytokine profile is characterized by high concentrations of IL-12p40, IL-18, and IFN-γ, paralleled by an expansion of ILC precursors (ILCPs). In the presence of the gliadin peptides p31-43 and pα-9, ILCPs from CD patients increase transglutaminase 2 (TG2) expression, produce IL-18 and IFN-γ, and stimulate CD4+ T lymphocytes. IFN-γ is also produced upon stimulation with IL-12p40 and IL-18 and is inhibited by the addition of vitamin D. Low levels of blood vitamin D correlate with high IFN-γ and ILCP presence and mark the CD population mostly affected by extraintestinal symptoms. Dietary vitamin D supplementation appears to be an interesting therapeutic approach to dampen ILCP-mediated IFN-γ production.

Asunto(s)

Enfermedad Celíaca , Inmunidad Innata , Enfermedad Celíaca/inmunología , Enfermedad Celíaca/metabolismo , Gliadina/metabolismo , Gliadina/farmacología , Humanos , Subunidad p40 de la Interleucina-12/metabolismo , Interleucina-18/metabolismo , Mucosa Intestinal/metabolismo , Linfocitos/metabolismo , Vitamina D/metabolismo , Vitamina D/farmacología

RESUMEN

Gluten proteins are responsible for the wheat breadmaking quality. However, gluten is also related to human pathologies for which the only treatment is a gluten-free diet (GFD). GFD has gained popularity among individuals who want to reduce their gluten intake. Tritordeum is a cereal species that originated after crossing durum wheat with wild barley and differs from bread wheat in its gluten composition. In this work, we have characterized the immunogenic epitopes of tritordeum bread and results from a four-phase study with healthy adults for preferences of bread and alterations in the gut microbiota after consuming wheat bread, gluten-free bread, and tritordeum bread are reported. Tritordeum presented fewer peptides related to gluten proteins, CD-epitopes, and IgE binding sites than bread wheat. Participants rated tritordeum bread higher than gluten-free bread. Gut microbiota analysis revealed that the adherence to a strict GFD involves some minor changes, especially altering the species producing short-chain fatty acids. However, the short-term consumption of tritordeum bread does not induce significant changes in the diversity or community composition of the intestinal microbiota in healthy individuals. Therefore, tritordeum bread could be an alternative for healthy individuals without wheat-related pathologies who want to reduce their gluten consumption without harming their gut health.

RESUMEN

Wheat gluten peptides (WGPs), identified as Leu-Leu (LL), Leu-Leu-Leu (LLL), and Leu-Met-Leu (LML), were tested for their impacts on cell growth, membrane lipid composition, and membrane homeostasis of yeast under ethanol stress. The results showed that WGP supplementation could strengthen cell growth and viability and enhance the ethanol stress tolerance of yeast. WGP supplementation increased the expressions of OLE1 and ERG1 and enhanced the levels of oleic acid (C18:1) and ergosterol in yeast cell membranes. Moreover, LLL and LML exhibited a better protective effect for yeast under ethanol stress compared to LL. LLL and LML supplementation led to 20.3 ± 1.5% and 18.9 ± 1.7% enhancement in cell membrane fluidity, 21.8 ± 1.6% and 30.5 ± 1.1% increase in membrane integrity, and 26.3 ± 4.8% and 27.6 ± 4.6% decrease in membrane permeability in yeast under ethanol stress, respectively. The results from scanning electron microscopy (SEM) elucidated that WGP supplementation is favorable for the maintenance of yeast cell morphology under ethanol stress. All of these results revealed that WGP is an efficient enhancer for improving the ethanol stress tolerance of yeast by regulating the membrane lipid composition.

Asunto(s)

Etanol , Saccharomyces cerevisiae , Membrana Celular/metabolismo , Etanol/metabolismo , Glútenes/metabolismo , Lípidos de la Membrana/química , Péptidos/metabolismo , Saccharomyces cerevisiae/metabolismo , Triticum/metabolismo

RESUMEN

Antimicrobial peptides (AMPs) have been reported to be promising alternatives to chemical preservatives. Thus, this study aimed to characterise AMPs generated from the hydrolysis of wheat gluten proteins using latex peptidases of Calotropis procera, Cryptostegia grandiflora, and Carica papaya. The three hydrolysates (obtained after 16 h at 37 °C, using a 1: 25 enzyme:  substrate ratio) inhibited the growth of Aspergillus niger, A. chevalieri, Trichoderma reesei, Pythium oligandrum, Penicillium sp., and Lasiodiplodia sp. by 60-90%, and delayed fungal growth on bread by 3 days when used at 0.3 g/kg. Moreover, the specific volume and expansion factor of bread were not affected by the hydrolysates. Of 28 peptides identified, four were synthesised and exhibited activity against Penicillium sp. Fluorescence and scanning electron microscopy suggested that the peptides damaged the fungal plasma membrane. Bioinformatics analysis showed that no peptide was toxic and that the antigenic ones had cleavage sites for trypsin or pepsin.

Asunto(s)

Calotropis , Látex , Péptidos Antimicrobianos , Aspergillus niger , Pan , Péptido Hidrolasas , Péptidos

RESUMEN

Background: We have focused on the alteration of the PD-1/PD-L1 pathway in celiac disease and discussed the roles of the PD1 pathway in regulating the immune response. We explored the idea that the altered mRNA splicing process in key regulatory proteins could represent a novel source to identify diagnostic, prognostic, and therapeutic targets in celiac disease. Methods: We characterized the PD1 mRNA variants' profile in CD patients and in response to gluten peptides' incubation after in vitro experiments. Total RNA from whole blood was isolated, and the coding region of the human PD-1 mRNA was amplified by cDNA PCR. Results: PCR amplification of the human PD-1 coding sequence revealed an association between the over-expression of the sPD-1 protein and the PD-1Δex3 transcript in celiac disease. Thus, we have found three novel alternative spliced isoforms, two of which result in a truncated protein and the other isoform with a loss of 14 aa of exon 2 and complete exon 3 (Δ3) which could encode a new soluble form of PD1 (sPD-1). Conclusions: Our study provides evidence that dietary gluten can modulate processes required for cell homeostasis through the splicing of pre-mRNAs encoding key regulatory proteins, which represents an adaptive mechanism in response to different nutritional conditions.

Asunto(s)

Empalme Alternativo , Enfermedad Celíaca/genética , Regulación de la Expresión Génica , Receptor de Muerte Celular Programada 1/genética , Antígeno B7-H1/metabolismo , Biomarcadores , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/metabolismo , Enfermedad Celíaca/terapia , Niño , Citocinas/biosíntesis , Susceptibilidad a Enfermedades , Femenino , Humanos , Inmunohistoquímica , Interferón gamma/metabolismo , Masculino , Péptidos/inmunología , Péptidos/metabolismo , Polimorfismo de Nucleótido Simple , Pronóstico , Proteína 2 Ligando de Muerte Celular Programada 1/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Transducción de Señal

RESUMEN

BACKGROUND: Although experts agree that strict dietary compliance is fundamental for the health of celiac patients, there are no evidence-based recommendations on the best way to assess dietary compliance. Detection of gluten immunogenic peptides (GIPs) in feces was recently proposed as an effective method of assessing the dietary compliance of celiac patients. METHODS: Fifty-five consecutive celiac patients (27 adults and 28 children, age 6-72 years), who had been on a gluten-free diet for at least 2 years, were enrolled. All patients were evaluated clinically for symptoms, physical parameters and laboratory parameters. Dietary compliance was assessed with the Biagi questionnaire and serum anti-tissue transglutaminase (tTG) IgA antibodies were measured. GIPs were determined by immunoenzymatic assay on an automated Chorus analyzer (DIESSE Diagnostica Senese), after extraction of fecal samples by the method developed by DIESSE. RESULTS: Eight patients tested positive for GIPs (GIPs+); 71.4% of GIP-positive patients were asymptomatic; tTG antibodies were detected in 3/8 GIP+ patients. The Biagi score was significantly associated with fecal positivity for GIPs (P=0.02). However, according to the Biagi score, 57.1% of GIP+ patients followed the diet strictly and 5.4% of GIP- subjects did not comply with the diet or made substantial mistakes. CONCLUSIONS: Assay of fecal GIPs identified more patients who did not comply with the diet than did the Biagi questionnaire, evaluation of symptoms or anti-tTG antibodies. Detection of fecal GIPs offers a direct, objective, quantitative assessment of even occasional exposure to gluten and is confirmed as a practical way to check dietary compliance.

RESUMEN

The reasons behind the increasing prevalence of celiac disease (CD) worldwide are still not fully understood. This study adopted a multilevel approach (in vitro, ex vivo, in vivo) to assess the potential of gluten from different wheat varieties in triggering CD. Peptides triggering CD were identified and quantified in mixtures generated from simulated gastrointestinal digestion of wheat varieties (n = 82). Multivariate statistics enabled the discrimination of varieties generating low impact on CD (e.g., Saragolla) and high impact (e.g., Cappelli). Enrolled subjects (n = 46) were: 19 healthy subjects included in the control group; 27 celiac patients enrolled for the in vivo phase. Celiacs were divided into a gluten-free diet group (CD-GFD), and a GFD with Saragolla-based pasta group (CD-Sar). The diet was followed for 3 months. Data were compared between CD-Sar and CD-GFD before and after the experimental diet, demonstrating a limited ability of Saragolla to trigger immunity, although not comparable to a GFD. Ex vivo studies showed that Saragolla and Cappelli activated immune responses, although with great variability among patients. The diverse potential of durum wheat varieties in triggering CD immune response was demonstrated. Saragolla is not indicated for celiacs, yet it has a limited potential to trigger adverse immune response.

Asunto(s)

Enfermedad Celíaca/dietoterapia , Glútenes/uso terapéutico , Triticum/química , Adolescente , Adulto , Anciano , Enfermedad Celíaca/inmunología , Niño , Preescolar , Dieta Sin Gluten , Digestión , Femenino , Glútenes/administración & dosificación , Humanos , Inmunidad , Italia , Masculino , Persona de Mediana Edad , Péptidos , Adulto Joven

RESUMEN

The impact of Aqualysin 1 (Aq1), the thermo-active peptidase of Thermus aquaticus, on wheat albumin, globulin, gliadin and glutenin proteins during heat treatment of wheat dough and bread baking was examined. The level of protein extractable in sodium dodecyl sulfate containing medium under non-reducing conditions (SDS-EP-NR) from wheat dough decreases upon heating to a lesser extent when Aq1 is used than in control experiments. The higher SDS-EP-NR level is caused by the release by Aq1 of peptides from the repetitive gluten protein domains during baking. These peptides are also extractable from bread crumb with salt solution. The resultant thermoset gluten network in bread crumb is mainly made up by protein from non-repetitive gluten domains.

Asunto(s)

Pan/análisis , Glútenes/química , Péptido Hidrolasas/metabolismo , Thermus/enzimología , Triticum/metabolismo , Culinaria , Harina/análisis , Glútenes/metabolismo , Peso Molecular , Dodecil Sulfato de Sodio/química , Temperatura

RESUMEN

In celiac disease (CD), an intolerance to dietary gluten/gliadin, antigenic gliadin peptides trigger an HLA-DQ2/DQ8-restricted adaptive Th1 immune response. Epithelial stress, induced by other non-antigenic gliadin peptides, is required for gliadin to become fully immunogenic. We found that cystic-fibrosis-transmembrane-conductance-regulator (CFTR) acts as membrane receptor for gliadin-derived peptide P31-43, as it binds to CFTR and impairs its channel function. P31-43-induced CFTR malfunction generates epithelial stress and intestinal inflammation. Maintaining CFTR in an active open conformation by the CFTR potentiators VX-770 (Ivacaftor) or Vrx-532, prevents P31-43 binding to CFTR and controls gliadin-induced manifestations. Here, we evaluated the possibility that the over-the-counter nutraceutical genistein, known to potentiate CFTR function, would allow to control gliadin-induced alterations. We demonstrated that pre-treatment with genistein prevented P31-43-induced CFTR malfunction and an epithelial stress response in Caco-2 cells. These effects were abrogated when the CFTR gene was knocked out by CRISP/Cas9 technology, indicating that genistein protects intestinal epithelial cells by potentiating CFTR function. Notably, genistein protected gliadin-sensitive mice from intestinal CFTR malfunction and gliadin-induced inflammation as it prevented gliadin-induced IFN-γ production by celiac peripheral-blood-mononuclear-cells (PBMC) cultured ex-vivo in the presence of P31-43-challenged Caco-2 cells. Our results indicate that natural compounds capable to increase CFTR channel gating might be used for the treatment of CD.

Asunto(s)

Enfermedad Celíaca/prevención & control , Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Genisteína/farmacología , Gliadina/toxicidad , Fragmentos de Péptidos/toxicidad , Animales , Células CACO-2 , Enfermedad Celíaca/etiología , Enfermedad Celíaca/fisiopatología , Regulador de Conductancia de Transmembrana de Fibrosis Quística/antagonistas & inhibidores , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Suplementos Dietéticos , Modelos Animales de Enfermedad , Femenino , Técnicas de Inactivación de Genes , Gliadina/inmunología , Humanos , Interferón gamma/biosíntesis , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Mucosa Intestinal/fisiopatología , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Biológicos , Fragmentos de Péptidos/inmunología , Unión Proteica

RESUMEN

Germination is already a well-accepted process by consumers with many products made from sprouted seeds or containing limited amounts of flour form sprouted grains. The present work aimed assessing the usefulness of germination in reducing gluten peptides associated with celiac disease, at the same time evaluating some technological features of the obtained germinated wheat. In the first part of the work, celiac disease (CD)-triggering peptides were tracked as a function of germination kinetics (from day 1 to day 6). Using simulated gastrointestinal digestion and liquid chromatography coupled to mass spectrometry, ten celiac disease triggering peptides were identified: seven peptides presumably involved in the adaptive immune response (TI) and three peptides mainly involved in the innate immune response (TT). All the identified peptides belonged to gliadins. TI track pattern showed three phases: the first two days displayed a significant degradation, a stability phase was observed from day 3 to day 5, and finally a drastic reduction occurred on the 6th day. For TT peptides, important degradation was exclusively observed at the 6th day. In the second part, some techno-functional features of germinated whole wheat flour were assessed to estimate its potential as an alternative to conventional flour. Functionality comparison of the non-germinated versus germinated flours revealed that germination significantly influenced solvents retention capacities as well as swelling and solubility. Thus, with a reduced amount of celiac disease triggering peptides, but also with different technological behavior compared to traditional wheat flour.

Asunto(s)

Enfermedad Celíaca/prevención & control , Harina/análisis , Germinación , Glútenes/metabolismo , Fragmentos de Péptidos/metabolismo , Triticum/metabolismo , Granos Enteros/metabolismo , Enfermedad Celíaca/inmunología , Cromatografía Líquida de Alta Presión , Digestión , Harina/efectos adversos , Análisis de los Alimentos/métodos , Manipulación de Alimentos/métodos , Glútenes/efectos adversos , Glútenes/inmunología , Humanos , Cinética , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/inmunología , Medición de Riesgo , Factores de Riesgo , Espectrometría de Masa por Ionización de Electrospray , Triticum/efectos adversos , Triticum/crecimiento & desarrollo , Triticum/inmunología , Granos Enteros/efectos adversos , Granos Enteros/crecimiento & desarrollo , Granos Enteros/inmunología

RESUMEN

Coeliac disease is an autoimmune enteropathy that develops in genetically predisposed subjects after the ingestion of gluten or related proteins. Coeliac disease has an increasing incidence in the last years in western countries and it has been suggested that wheat breeding might have contributed to select more toxic forms of gluten. In this work, we analysed gluten peptides generated by in vitro digestion of different old and modern Triticum varieties, using LC-MS. We concluded that old varieties analysed produced a higher quantity of peptides containing immunogenic and toxic sequences than modern ones. Thus old wheat lines are not to be considered "safer" for subjects that are genetically predisposed to celiac disease.

Asunto(s)

Enfermedad Celíaca/inmunología , Digestión , Glútenes/metabolismo , Fragmentos de Péptidos/metabolismo , Triticum/metabolismo , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/genética , Predisposición Genética a la Enfermedad , Glútenes/efectos adversos , Glútenes/inmunología , Humanos , Epítopos Inmunodominantes , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/inmunología , Mapeo Peptídico/métodos , Medición de Riesgo , Factores de Riesgo , Triticum/efectos adversos , Triticum/clasificación , Triticum/inmunología