Selection of lactic acid bacteria strains for the hydrolysis of allergenic proteins of wheat flour

BACKGROUND

Wheat flour is one of the most common causative agents of food allergy. The study presents the selection and characterization of lactic acid bacteria (LAB) strains capable of hydrolyzing/modifying allergenic proteins of wheat flour. Hydrolysis of wheat proteins was determined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with sera from patients with food allergy to gluten.

RESULTS

The analysis of electrophoretic profiles of protein extracted from sourdough shows the capability of selected LAB strains for proteolytic degradation of wheat proteins that belong to two factions: albumin/globulin (hydrolysis of 13 polypeptides with a molecular weight between 103 and 22 kDa); and gliadin (seven polypeptides with a molecular weight between 39 and 24 kDa). All analyzed strains were capable of hydrolyzing some IgE-binding epitopes of wheat allergens. The lack of such changes in control samples indicates that they were induced rather by the proteolytic activity of bacterial strains than endogenous enzymes of wheat flour. The gluten proteins were susceptible to hydrolysis by sequential digestion with pepsin and trypsin.

CONCLUSION

The selected strains exhibit proteolytic activity, which leads to a reduction in allergenicity of wheat sourdoughs. These strains may be applied as specific starter cultures to prepare bakery products of special nutritional use. © 2015 Society of Chemical Industry.

Other Dietary Confounders: FODMAPS et al

BACKGROUND

While it is well documented and widely appreciated that ingestion of wheat (and less so rye and barley) is associated with gastrointestinal symptoms such as bloating or abdominal pain, the component of wheat to which such an effect is attributed is less well established.

KEY MESSAGES

Wheat is a complex of proteins (80% gluten, 20% metabolic proteins), carbohydrates (starch, non-starch polysaccharides, fructans), lipids and other components. The majority of attention has focused on gluten as the culprit in triggering symptoms, but re-challenge studies have nearly all used wheat flour-related products (such as bread) as the stimulus. When carbohydrate-deplete gluten was used as the challenge agent, gluten-specific feelings of depression and not gut symptoms were observed in those who fulfilled strict criteria of 'non-coeliac gluten sensitivity', thereby underlining the complexity of cereals and of undertaking research in this area. Candidate components other than gluten include poorly absorbed oligosaccharides (mainly fructans), non-gluten wheat proteins such as amylase-trypsin inhibitors or wheat germ agglutinin, and exorphins released during the digestion of gluten. Specific biological and/or clinical effects associated with gluten-free diets or wheat ingestion need to be carefully dissected before attribution to gluten can be claimed.

CONCLUSIONS

Currently, coeliac disease is the only common condition that has been unequivocally linked to gluten. Inaccurate attribution will be associated with suboptimal therapeutic advice and at least partly underlies the current gluten-free epidemic gripping the Western world.

Involvement of heat shock proteins in gluten-sensitive enteropathy

Gluten-sensitive enteropathy, also known as coeliac disease (CD), is an autoimmune disorder occurring in genetically susceptible individuals that damages the small intestine and interferes with the absorption of other nutrients. As it is triggered by dietary gluten and related prolamins present in wheat, rye and barley, the accepted treatment for CD is a strict gluten-free diet. However, a complete exclusion of gluten-containing cereals from the diet is often difficult, and new therapeutic strategies are urgently needed. A class of proteins that have already emerged as drug targets for other autoimmune diseases are the heat shock proteins (HSPs), which are highly conserved stress-induced chaperones that protect cells against harmful extracellular factors. HSPs are expressed in several tissues, including the gastrointestinal tract, and their levels are significantly increased under stress circumstances. HSPs exert immunomodulatory effects, and also play a crucial role in the maintenance of epithelial cell structure and function, as they are responsible for adequate protein folding, influence the degradation of proteins and cell repair processes after damage, and modulate cell signalling, cell proliferation and apoptosis. The present review discusses the involvement of HSPs in the pathophysiology of CD. Furthermore, HSPs may represent a useful therapeutic target for the treatment of CD due to the cytoprotective, immunomodulatory, and anti-apoptotic effects in the intestinal mucosal barrier.

A new reliable method for detecting specific IgE antibodies in the patients with immediate type wheat allergy due to hydrolyzed wheat protein: correlation of its titer and clinical severity

BACKGROUND

Immediate-type wheat allergy caused by a specific hydrolyzed wheat protein (HWP-IWA), Glupearl 19S (GP19S), typically develops food-dependent exercise-induced anaphylaxis (FDEIA), but is different from conventional FDEIA, or simple wheat allergy in many aspects. The skin prick test (SPT) is considered to be the most effective method for diagnosis of HWP-IWA. As SPT is a relatively qualitative method, we developed quantitative and high-throughput test method for HWP-IWA.

METHODS

An enzyme-linked immunosorbent assay (ELISA)-based GP19S-specific IgE assay was tested using sera from 14 HWP-IWA and five conventional wheat-dependent exercise-induced anaphylaxis (CO-WDEIA) patients, as well as five healthy subjects. Then a validation study at five different institutions was carried out using sera from 10 HWP-IWA and five CO-WDEIA patients, as well as five healthy subjects different from the previous studies.

RESULTS

The mean unit values converted from measured absorbance of ELISA were 68.3, 1.3 and 1.1 respectively. Furthermore, the validation study revealed reproducible results across all five institutions, with the standard deviation (SD) being 0.3-0.4 for the healthy group, 0.2-0.6 for the CO-WDEIA group, and 3.8-9.6 for HWP-IWA group except for one case. One case of HWP-IWA was excluded from analysis due to the high SD of 53.3 units, indicating that samples with a unit value > 100.0 will affect inter-laboratory reproducibility.

CONCLUSIONS

Our findings suggest that the ELISA-based GP19S-specific IgE assay can be used to test HWP-IWA using venous blood samples, except for those with a unit value > 100.0.

Nutritional properties of einkorn wheat (Triticum monococcum L.)

The hulled wheat einkorn (Triticum monococcum L. ssp. monococcum), a staple food of early farmers for many thousand years, today is cropped only in small areas of the Mediterranean region and continental Europe. Increasing attention to the nutritional quality of foods has fostered renewed interest in this low-impact crop. The reappraisal of einkorn quality evidenced that this ancient wheat has some dietary advantages over polyploid wheats. Einkorn wholemeal is poor in dietary fibre but rich in proteins, lipids (mostly unsaturated fatty acids), fructans and trace elements (including zinc and iron). The good concentration of several antioxidant compounds (carotenoids, tocols, conjugated polyphenols, alkylresorcinols and phytosterols) and low β-amylase and lipoxygenase activities (which limit antioxidant degradation during food processing) contribute to the excellent nutritional properties of its flour, superior to those of other wheats. Conversely, einkorn has relatively low bound polyphenol content and high polyphenol oxidase activity. In spite of eliciting weaker toxic reactions than other Triticum species, einkorn is not suitable for coeliacs. Current trends towards the consumption of functional foods suggest that this cereal may still play a significant role in human consumption, especially in the development of new or special foods with superior nutritional quality.

Maize prolamins could induce a gluten-like cellular immune response in some celiac disease patients

Celiac disease (CD) is an autoimmune-mediated enteropathy triggered by dietary gluten in genetically prone individuals. The current treatment for CD is a strict lifelong gluten-free diet. However, in some CD patients following a strict gluten-free diet, the symptoms do not remit. These cases may be refractory CD or due to gluten contamination; however, the lack of response could be related to other dietary ingredients, such as maize, which is one of the most common alternatives to wheat used in the gluten-free diet. In some CD patients, as a rare event, peptides from maize prolamins could induce a celiac-like immune response by similar or alternative pathogenic mechanisms to those used by wheat gluten peptides. This is supported by several shared features between wheat and maize prolamins and by some experimental results. Given that gluten peptides induce an immune response of the intestinal mucosa both in vivo and in vitro, peptides from maize prolamins could also be tested to determine whether they also induce a cellular immune response. Hypothetically, maize prolamins could be harmful for a very limited subgroup of CD patients, especially those that are non-responsive, and if it is confirmed, they should follow, in addition to a gluten-free, a maize-free diet.

Fermentable fibers do not affect satiety or food intake by women who do not practice restrained eating

BACKGROUND

Fiber is thought to enhance satiety, although not all fibers are equally effective. Colonic fermentation may influence satiety and food intake.

OBJECTIVE

To test the satiating properties of four isolated fibers added to chocolate crisp bars.

DESIGN

Within-subject preload design with repeated measures. Each participant completed five conditions, presented in random order.

SUBJECTS

Participants were 22 adult women who do not practice restrained eating (body mass index 18 to 29).

INTERVENTION

The experimental conditions were four fiber treatments: 10 g oligofructose, inulin, soluble corn fiber, or resistant wheat starch in chocolate crisp bars. A no-added-fiber bar was evaluated as the control. The night before each treatment, participants consumed a dinner bar containing 10 g of the same fiber given the next morning.

MAIN OUTCOME MEASURES

Repeated ratings of feelings related to hunger and fullness at the lunch meal were the main measures. Secondary outcomes included breath hydrogen and methane, gastrointestinal symptoms, energy consumed at an ad libitum lunch, and energy from 24-hour dietary recall.

STATISTICAL ANALYSES PERFORMED

Mixed-effect linear models with random intercept for participants to model within-subject correlation.

RESULTS

All treatments were well tolerated. No differences were found in subjective satiety during the morning or food intake at lunch or over 24 hours. The oligofructose bar produced the greatest increase in breath hydrogen, and the most bloating and flatulence symptoms.

CONCLUSIONS

Functional fibers incorporated into chocolate bars at high fiber doses produce greater gastrointestinal symptoms than control, but do not alter satiety, hunger, or food intake compared with control in the short term.

Review article: coeliac disease, new approaches to therapy

BACKGROUND

Coeliac disease is managed by life-long gluten withdrawal from the diet. However, strict adherence to a gluten-free diet is difficult and is not always effective. Novel therapeutic approaches are needed to supplement or even replace the dietary treatment.

AIM

To review recent advances in new therapeutic options for coeliac disease.

METHODS

A literature search was performed on MEDLINE, EMBASE, Web of Science, Scopus, DDW.org and ClinicalTrials.gov for English articles and abstracts. The search terms used included, but not limited to, 'Celiac disease', 'new', 'novel', 'Advances', 'alternatives' and 'Drug therapy'. The cited articles were selected based on the relevancy to the review objective.

RESULTS

Several new therapeutic approaches for coeliac disease are currently under development by targeting its underlying pathogenesis. Alternative therapies range from reproduction of harmless wheat strains to immunomodulatory approaches. Some of these therapies such as enzymatic cleavage of gluten and permeability inhibitors have shown promise in clinical studies.

CONCLUSIONS

Gluten-free diet is still the only practical treatment for patients with coeliac disease. Novel strategies provide promise of alternative adjunctive approaches to diet restriction alone for patients with this disorder.

[The sensitivity and clinical course of patients with wheat-dependent exercise-induced anaphylaxis sensitized to hydrolyzed wheat protein in facial soap]

BACKGROUND

Recently an increasing number of patients with wheat-dependent exercise-induced anaphylaxis (WDEIA), developed during or after using hydrolyzed wheat protein (HWP)-containing soap (HWP-WDEIA), were reported in Japan.

METHODS

To clarify the relation between WDEIA and HWP-containing soap and their prognosis, we investigated the patients who visited Hiroshima University Hospital and were diagnosed as WDEIA from January 2010 to June 2011. We took detailed clinical histories, performed skin prick tests, serum immunoassays for antigen-specific IgE and basophil histamine release test, and followed up their clinical courses after the diagnosis.

RESULTS

Among 36 patients with WDEIA, 30 patients had used only one type of HWP-soap. The patients with HWP-WDEIA were mainly women and had developed facial symptoms and angioedema. They suffered from blood pressure reductions less frequently than patients with conventional WDEIA. The levels of glutens-specific IgE were higher than those of ω-5 gliadin in patients with HWP-WDEIA (p<0.05, One-way ANOVA). All patients with HWP-WDEIA were positive against HWP in histamine release test. Among the conventional wheat antigens, glutenins induced highest histamine release from basophils of patients with HWP-WDEIA. The sensitivities of patients against glutens and glutenins were reduced over months along with the discontinuance of HWP-soap.

CONCLUSIONS

The development of HWP-WDEIA is associated with the use of HWP-soap. The sensitivities to HWP that cross reacts with non-processed wheat may be reduced or possibly cured after the discontinuation of HWP-soap.

[Asthma and baker's allergy: experience with health programs]

Wheat flour sensitization may lead to several occupational diseases: persistent rhinitis, intermittent or persistent asthma, conjunctivitis, urticaria, and contact dermatitis. The main allergenic components of wheat have been identified, the prevalent mechanism is IgE-mediated, the worsening after starting of sensitization shows the characters of the "allergy march" till the respiratory functional impairment and disability. Nowadays the occupational rhinitis is the first important step to begin to start prevention, but its relevance is also for quality of life of subjects. Data about the prevalence of the sensitization in Italy seem to be spread, ranging from 4% to 24% in the literature and till 32% in a recent our investigation. A complete and early diagnosis is essential to manage the allergic bakers, aiming relocation in their own activity. A specific immunotherapy by allergenic vaccine has been studied and it is now possible. In our experience 43 bakers and pastry makers were treated by the same vaccine (Lofarma Laboratories, Milan) and revalued after many years; 83% were still at work and 70% claimed only poor or no-symptoms during work, in any way with a tolerable condition. At present the baker's disease may be managed by included interventions "man-environment" avoiding the extreme choice of leaving the working activity. The Lombardy Government published specific Guide Lines on the prevention and proposed a planned project for three years, to be adopted according to local needs in collaboration with the public health service.

The effect of past food avoidance due to allergic symptoms on the growth of children at school age

BACKGROUND

The influence of food avoidance due to allergic symptoms in infancy on the growth of children at school age has not been well evaluated.

METHODS

To determine the growth of schoolchildren who avoided eggs, milk, or wheat due to immediate allergic symptoms in infancy (food avoiders in infancy) (FAI), a questionnaire on the presence of allergic diseases, as well as present height and weight, was administered to the parents of 14,669 schoolchildren. 11,473 subjects had available data. The height and weight standard deviation scores (HtSDS and WtSDS) and body mass index percentile (BMI percentile) of each subject were calculated.

RESULTS

FAI had significantly lower WtSDS than non-FAI (P = 0.01). Among those with avoidance at age 3 years, those who avoided two or more foods and those who avoided milk had significantly lower HtSDS than their counterparts (P = 0.02 and 0.04, respectively). FAI had a significantly lower prevalence of obesity (P = 0.01) and overweight (P = 0.002), while there was no difference in the prevalence of underweight (P = 0.58), resulting in a significantly higher prevalence of appropriate weight (P = 0.01) compared to non-FAI. Significantly lower prevalence of obesity and overweight was observed even among those who terminated the avoidance by age 3 years.

CONCLUSIONS

FAI were less likely to be obese or overweight, resulting in a higher prevalence of appropriate weight at school age. Further investigation should contribute to better management of food allergy and obesity.

Infant and childhood diet and type 1 diabetes risk: recent advances and prospects

Type 1 diabetes is a chronic autoimmune disease characterized by a preclinical period of autoimmunity. It is well accepted that both genetic and environmental factors contribute to disease risk. Given that type 1 diabetes, and its preclinical autoimmunity, appear early in life, infant and childhood diet have been implicated as potential initiating exposures in the etiology of the disease. Several publications in the past year have provided further evidence for existing hypotheses regarding the roles of wheat, cow's milk, omega-3 fatty acids, and the maternal diet during pregnancy. However, inconsistencies in findings between studies suggest the need for collaboration and standardization of study methods to move forward in research in this area. One such example of this is the TEDDY (The Environmental Determinants of Diabetes in the Young) study, which is an international, multicenter birth cohort study with standardized recruitment, dietary collection methodologies, and analytic approaches.