Combination of Gluten-Digesting Enzymes Improved Symptoms of Non-Celiac Gluten Sensitivity: A Randomized Single-blind, Placebo-controlled Crossover Study

In vitro simulated study of macronutrient digestion in complex food using digestive enzyme supplement

Digestive enzymes secreted by the body are vital for digestion and nutrient absorption. Enzyme supplements are commonly used to support them in achieving optimal digestion. Herein, the efficacy of digestive enzyme supplement (DigeSEB Super) in digestion of complex food was assessed using INFOGEST simulated static and modified semi-dynamic in vitro digestion models. Digestive enzyme supplement was found to assist the endogenous digestive enzymes to disintegrate the food matrix. Hence, it reduced the viscosity of the gastric digesta by 2.75 fold (p = 0.04) compared to the control digestion (only endogenous digestive enzymes) during the first hour of digestion. Similarly, enzyme supplement showed statistically higher release of reducing sugars in the gastric digestion (p ≤ 0.05) indicating improved digestion of carbohydrates. Further, digestion of proteins and fats was also improved in the presence of enzyme supplement. The kinetic aspects of the semi-dynamic model (transient nature of gastric secretions and gradual acidification) was found to alter the macronutrient digestion compared to the static digestion. Thus, semi-dynamic model should be preferred for the in vitro studies. Overall, current study demonstrated the potential of a digestive enzyme supplement to improve digestion by aiding digestive action of the endogenous enzymes.

The Gliadin Hydrolysis Capacity of B. longum, L. acidophilus, and L. plantarum and Their Protective Effects on Caco-2 Cells against Gliadin-Induced Inflammatory Responses

BACKGROUND

Non-celiac wheat sensitivity (NCWS) is a poorly understood gluten-related disorder (GRD) and its prominent symptoms can be ameliorated by gluten avoidance. This study aimed to determine the effectiveness of a probiotic mixture in hydrolyzing gliadin peptides (toxic components of gluten) and suppressing gliadin-induced inflammatory responses in Caco-2 cells.

METHODS

Wheat dough was fermented with a probiotic mix for 0, 2, 4, and 6 h. The effect of the probiotic mix on gliadin degradation was monitored by SDS-PAGE. The expression levels of IL-6, IL-17A, INF-γ, IL-10, and TGF-β were evaluated using ELISA and qRT-PCR methods.

RESULTS

According to our findings, fermenting wheat dough with a mix of B. longum, L. acidophilus, and L. plantarum for 6 h was effective in gliadin degradation. This process also reduced levels of IL-6 (p = 0.004), IL-17A (p = 0.004), and IFN-γ (p = 0.01) mRNA, as well as decreased IL-6 (p = 0.006) and IFN-γ (p = 0.0009) protein secretion. 4 h fermentation led to a significant decrease in IL-17A (p = 0.001) and IFN-γ (p = 0.003) mRNA, as well as reduced levels of IL-6 (p = 0.002) and IFN-γ (p < 0.0001) protein secretion. This process was also observed to increase the expression levels of IL-10 (p < 0.0001) and TGF-β (p < 0.0001) mRNA.

CONCLUSIONS

4 h fermentation of wheat flour with the proposed probiotic mix might be a good strategy to develop an affordable gluten-free wheat dough for NCWS and probably other GRD patients.

Is it time to rethink the burden of non-coeliac gluten sensitivity? A systematic review

INTRODUCTION

Non-coeliac gluten sensitivity (NCGS) is still a poorly defined clinical condition. This review aims to describe the clinical features of subjects with a symptomatic response to gluten intake, and to estimate the prevalence of NCGS.

EVIDENCE ACQUISITION

Literature search was conducted in accordance with PRISMA recommendations. The PubMed database was searched for original articles until 1^st June 2020.

EVIDENCE SYNTHESIS

We identified 30 relevant articles, including 14 studies that investigated NCGS through a double-blind, placebo-controlled crossover trial (DBPCC), and 16 that examined the role of gluten in causing symptoms without a DBPCC. We found that regardless of the diagnostic work up, gluten-sensitive patients were predominately middle-aged females complaining of abdominal pain, bloating and diarrhea. The pooled prevalence of NCGS after DBPCC was 24% (5-34%). Subjects with irritable bowel syndrome or self-reporting gluten intolerance accounted for the vast majority of the patients who did not start a DBPCC. A symptomatic response to a gluten-free diet (GFD) occurred in between 7% and 93% of patients. No data on long-term outcomes of NCGS individuals were reported.

CONCLUSIONS

Clinical features of NCGS patients did not differ among all the included studies, whereas prevalence figures are rather heterogeneous. Long-term benefit of a GFD on these patients still needs to be ascertained.

Fungal digestive enzymes promote macronutrient hydrolysis in the INFOGEST static in vitro simulation of digestion

The objective of this study was to test the hydrolytic efficacy of 6 fungal enzymes in the INFOGEST static in vitro simulation of gastrointestinal (GI) digestion. First, the INFOGEST protocol was adapted for testing of exogenous enzymes. Second, a dose-response study of 3 individual fungal proteases, a lipase, and an amylase with glucoamylase demonstrated improved dietary protein, lipid, and carbohydrate hydrolysis, respectively, from an oral nutritional supplement (ONS) under simulated gastric or GI conditions, compared to pepsin and pancreatin-based control conditions. Third, a combination of the 6 enzymes (BC-006) improved macronutrient digestion, including enhanced release of individual amino acids from ONS and mixed meal substrates. Finally, we validated digestive models of aging and proton pump inhibitor (PPI) use, and showed that BC-006 improved gastric digestion under these compromised digestive conditions. The INFOGEST static simulation is a feasible tool to rapidly screen and profile exogenous enzymes for digestive efficacy in vitro.

Hydrolytic enzymes and their directly and indirectly effects on gluten and dough properties: An extensive review

Poor water solubility, emulsifying, and foaming properties of gluten protein have limited its applications. Gluten is structured by covalent (disulfide bonds) and noncovalent bonds (hydrogen bonds, ionic bonds, hydrophobic bonds) which prone to alteration by various treatments. Enzyme modification has the ability to alter certain properties of gluten and compensate the deficiencies in gluten network. By hydrolyzing mechanisms and softening effects, hydrolytic enzymes affect gluten directly and indirectly and improve dough quality. The present review investigates the effects of some hydrolytic enzymes (protease and peptidase, alcalase, xylanase, pentosanase, and cellulase) on the rheological, functional, conformational, and nutritional features of gluten and dough. Overall, protease, peptidase, and alcalase directly affect peptide bonds in gluten. In contrast, arabinoxylan, pentosan, and cellulose are affected, respectively, by xylanase, pentosanase, and cellulase which indirectly affect gluten proteins. The changes in gluten structure by enzyme treatment allow gluten for being used in variety of purposes in the food and nonfood industry.

More fuel to the fire: some patients with non-celiac self-reported wheat sensitivity exhibit adaptive immunological responses in duodenal mucosa

Background

In contrast to the well-characterized Celiac Disease (CD), the clinical scenarios encompassed by the non-celiac self-reported wheat sensitivity (NCSRWS) might be related to different antigens that trigger distinct immune-inflammatory reactions. Although an increased number of intestinal intraepithelial lymphocytes is observed at the inception of both diseases, the subsequent immunopathogenic pathways seem to be different. We aimed to describe the cytokine profile observed in the duodenal mucosa of patients with NCSRWS.

Methods

In a blind, cross-sectional study, we included duodenal biopsies from 15 consecutive untreated patients with active CD, 9 individuals with NCSRWS and 10 subjects with dyspepsia without CD and food intolerances. Immunohistochemistry and flow-cytometry were used to determine the presence of pro-inflammatory cytokine expressing monocytes and monocyte-derived dendritic cells involved in innate immune activation, cytokine-driven polarization and maintenance of Th1 and Th17/Th 22, and anti-inflammatory/profibrogenic cytokines.

Results

The percentage of cells expressing all tested cytokines in the lamina propria and the epithelium was higher in CD patients than in the control group. Cytokines that induce and maintain Th1 and Th17 polarization were higher in CD than in NCSRWS and controls, also were higher in NCSRWS compared to controls. Similar differences were detected in the expression of IL-4 and TGF-1, while IL-10-expressing cells were lower in NCSRWS patients than in controls and CD subjects.

Conclusions

NCSRWS patients exhibit components of both, innate and adaptive immune mechanisms but to a lesser extent compared to CD.

Nonceliac Gluten Sensitivity—A Masquerading IBS or a Real Phenomenon?

The gluten-free diet has become popular among the public. People who are using this diet have reported symptom relief once gluten has been removed from their diet. Nonceliac gluten sensitivity (NCGS) has emerged as a new diagnosis for those patients who have tested negative for celiac disease. Although there are no diagnostic markers established for NCGS, its symptomatology ranges from gastrointestinal symptoms to neuropsychiatric symptoms. Indeed, some of these symptoms are also seen in patients with irritable bowel syndrome (IBS), such as abdominal pain, bloating, altered bowel movement, diarrhea, and constipation. It is important to add that unlike celiac disease, NGCS has never been associated with any long-term malignancy. We aim to review the recent clinical data available on this topic and address the overlap symptoms between NCGS and IBS. We concluded that despite the overlap symptoms between both diseases, NCGS is a real clinical phenomenon that awaits its own diagnostic clinical criteria and specific laboratory markers. We suggest that patients with gluten sensitivity who are negative for celiac disease should be considered for NCGS.

Protein Digestibility of Cereal Products

Protein digestibility is currently a hot research topic and is of big interest to the food industry. Different scoring methods have been developed to describe protein quality. Cereal protein scores are typically low due to a suboptimal amino acid profile and low protein digestibility. Protein digestibility is a result of both external and internal factors. Examples of external factors are physical inaccessibility due to entrapment in e.g., intact cell structures and the presence of antinutritional factors. The main internal factors are the amino acid sequence of the proteins and protein folding and crosslinking. Processing of food is generally designed to increase the overall digestibility through affecting these external and internal factors. However, with proteins, processing may eventually also lead to a decrease in digestibility. In this review, protein digestion and digestibility are discussed with emphasis on the proteins of (pseudo)cereals.