Celiac disease: Alternatives to a gluten free diet

Effectiveness of high-fat and high-carbohydrate diets on body composition and maximal strength after 15 weeks of resistance training

PURPOSE

The aim of this study was to compare High Carbohydrates Low Fat (HCLF) and Low Carbohydrate High Fat (LCHF) diets in terms of changes in body composition and maximal strength.

PATIENTS/METHODS

The study involved 48 men aged 25 ​± ​2.5, divided into two groups, one of which (n ​= ​23) was following the LCHF diet and the other (n ​= ​25) the HCLF diet. Both groups performed the same resistance training protocol for 15 weeks. Maximal strength in squat, bench press and deadlift was assessed pre- and post-intervention. Measurements of selected body circumferences and tissue parameters were made using the multifunctional, multi-frequency, direct bioelectric impedance InBody 770 analyzer from InBody Co., Ltd (Cerritos, California, USA). The team with the necessary qualifications and experience in research performed all the measurements and maintained participants' oversight throughout the entire length of the study.

RESULTS

Both nutritional approaches were effective in terms of reducing body fat mass. The HCLF group achieved greater skeletal muscle hypertrophy. Significant decreases in body circumferences, especially in the abdominal area, were observed for both dietary approaches. Maximal strength significantly increased in the HCLF group and decreased in the LCHF group.

CONCLUSION

Holistic analysis of the results led to the conclusion that both dietary approaches may elicit positive adaptations in body composition. The two approaches constitute useful alternatives for both recreational exercisers and physique athletes with body composition goals.

Probiotic Potential and Gluten Hydrolysis Activity of Lactobacillus brevis KT16-2

Celiac disease (CD) is a chronic autoimmune disease that occurs in genetically predisposed individuals. Gluten-hydrolyzing probiotic bacteria are promising for alleviating symptoms in individuals with CD. Therefore, in this study, the gluten hydrolysis ability and probiotic potential of Lact. brevis KT16-2 were determined. Lact. brevis KT16-2 formed proteolysis zones on gluten and gliadin agar plates, in which gluten and gliadin were used as the only nitrogen sources. SDS-PAGE analysis showed that Lact. brevis KT16-2 completely hydrolyzed peptides ranging from 28 to 66 kDa in 8 h. Then, the survival of the strain in bile salts, in simulated gastric juice and at low pH was determined. Additionally, the antioxidant and antimicrobial substance production, autoaggregation, hydrophobicity and antibiotic resistance of the strain were investigated. API-ZYM test kits were used to determine the enzymatic capacity of the strain. Lact. brevis KT16-2 had the ability to hydrolyze wheat gluten. It was able to survive in a broad pH range (pH 2-8), in bile salts (0.3-1%), and in simulated gastric juice. It had the ability to autoaggregate (59.4%), and the hydrophobicity (52.7%) of the strain was determined. In addition, this strain was capable of producing antimicrobial peptides against test bacteria, including antibiotic-resistant bacteria. Cell-free supernatants (CFS) of the strain had high antioxidant activity (DPPH-71.0% and ABTS-54.1%). The results of this study suggest that Lact. brevis KT16-2, which can hydrolyze gliadin and has many essential probiotic properties, has the potential to be used as a probiotic supplement for individuals with CD.

A Peptide from Kiwifruit Exerts Anti-Inflammatory Effects in Celiac Disease Mucosa

Objective: Celiac disease is an immune-mediated disease of the intestine triggered by gluten. Gluten elicits, in genetically susceptible individuals, cytokine responses that are then transmitted to the immunocompetent cells. Vegetables and fruit have anti-inflammatory and antioxidant properties with a protective effect on intestinal epithelium. Kiwifruit is known to have beneficial effects on the intestinal tissues, and it is the only plant food containing the peptide kissper, with anti-inflammatory properties. The aim of this study was the evaluation of the kissper effect on the gluten-induced inflammation in celiac disease. Methods: We used an in vitro model of intestinal culture explant from celiac disease patients and non-celiac disease patients, cultured for 24 hours with the toxic gliadin peptide P31-43 and kissper preincubation. Results: Our data showed HLA-DR and TG2 reduction in the celiac disease mucosa pretreated with kissper, as well as a reduction of COX-2 in two patients. No differences we observed for the TGF-b1 and IL-15 levels in supernatants upon kissper pretreatment. Conclusions: The preliminary results suggest that kissper has a potential anti-inflammatory role in celiac disease.

Molecular insights on the interaction and preventive potential of epigallocatechin-3-gallate in Celiac Disease

Celiac Disease (CD) is now recognized as a worldwide epidemic. Although a gluten free diet usually induces clinical improvements within days or weeks, adhering to this routine is still troublesome. Therefore, new solutions are needed for quality-of-life improvement of CD patients. The present work intends to bring molecular and thermodynamic insights on the ability of green tea epigalhocatechin-3-gallate (EGCG) to interact and modulate the bioavailability of a major CD immunodominant peptide (32-mer). Characterization of peptide binding was assessed by means of both 1D and 2D ¹H NMR experiments, ITC and Molecular Dynamics simulations. Accordingly, EGCG not only exhibits a high reactivity towards the 32-mer peptide as its binding appears to be entropy-driven and involves two sequential binding events, each with different binding strengths. Structural rearrangements were also detected during the interaction, contributing to a greater stability of the formed complexes. In vitro transepithelial transport assays using a Caco-2 cell line model were also performed and highlighted the ability of EGCG to significantly reduce the concentration of free peptide in the basolateral compartment. Overall, this study provides important evidences regarding the structural features and molecular mechanisms by which EGCG could interact and potentially modulate the function of some bioactive CD peptides.

Comparable efficiency of different extraction protocols for wheat and rye prolamins

The identification and quantification of cereal storage proteins is of interest of many researchers. Their structural or functional properties are usually affected by the way how they are extracted. The efficiency of extraction process depends on the cereal source and working conditions. Here, we described various commonly used extraction protocols differing in the extraction conditions (pre-extraction of albumins/globulins, sequential extraction of individual protein fractions or co-extraction of gluten proteins, heating or non-heating, reducing or non-reducing conditions). The total protein content of all fractions extracted from commercially available wheat and rye flours was measured by the Bradford method. Tris-Tricine SDS-PAGE was used to determine the molecular weights of wheat gliadins, rye secalins and high-molecular weight glutelins which are the main triggering factors causing celiac disease. Moreover, we were able to distinguish individual subunits (α/β-, γ-, ω-gliadins and 40k-γ-, 75k-γ-, ω-secalins) of wheat/rye prolamins. Generally, modified extraction protocols against classical Osborne procedure were more effective and yields higher protein content in all protein fractions. Bradford measurement led into underestimation of results in three extraction procedures, while all protein fractions were clearly identified on SDS-PAGE gels. Co-extraction of gluten proteins resulted in appearance of both, low-molecular weight fractions (wheat gliadins and rye secalins) as well as high-molecular weight glutelins which means that is not necessary to extract gluten proteins separately. The two of three extraction protocols showed high technical reproducibility with coefficient of variation less than 20%. Carefully optimized extraction protocol can be advantageous for further analyses of cereal prolamins. 

Application of western blot analysis for detection of prolamin proteins in cereal grains and bread

Celiac disease is an inflammatory condition of the small intestine in genetically susceptible individuals caused by ingestion of wheat gluten and corresponding proteins from barley and rye. Cereal storage proteins (prolamins) are responsible for immunological response of patients with celiac disease. Prolamins are alcohol soluble fractions, namely gliadins (wheat), hordeins (barley) and secalins (rye). The main triggering factor is wheat fraction with low molecular weight (20-30 kDa) called α-gliadins. Immunochemical detection of celiac active proteins is based on reactivity of gluten-detecting antibodies with prolamins extracted from cereals. In our study, we used Western blot analysis for detection of prolamin complex in cereal grains and processed foods (breads). Western blot was carried out by polyclonal antibody raised against wheat gluten. Reaction was positive for all kind of cereal grains. The samples of wheat and spelt wheat show much more positive affinity to antibody than rye and oat. As well as for cereal grains, all samples of bread showed positive immunological reaction with used antibody. Western blot analysis with gluten polyclonal antibody is suitable method for qualitative detection of prolamin complex in cereal grains and processed foods.