ATI-DETOX Modification of functional properties of Amylase Trypsin Inhibitors by REDOX reactions to mitigate pathogenic effects
50-300 million people in the western world are affected with irritable bowel syndrome (IBS) or non-celiac wheat sensitivity (NCWS). There is broad scientific consensus that gluten is not the main cause of these pathologies and that other components in wheat, called Amylase Trypsin Inhibitors (ATIs), can play an important role. Partially informed by social media and due to lack of scientific mechanistic proof, consumers tend to avoid cereal-based products, which generally are the most important and cheap source of nutrients in our diet. Human in vitro and in vivo mice model studies have shown that ATIs play an important mechanistic role in IBS and NCWS, initiating intestinal inflammation and adaptive immune responses. ATIs are also the main allergens causing bakers asthma and eczema. ATIs account for about 5-15% of the total wheat grain proteins and up to two thirds of the water-soluble (albumin) protein fraction. ATIs are part of a large family of enzyme inhibitors in plants, that is characterized by a very stable protein structure (due to disulphide bridging) which confers protection to processing and gastrointestinal degradation. The redox status of ATIs has been shown to be a switch knob for its biofunctionality in various ways:
• Partial reduction of disulfide bonds in ATIs can double amylase and papain enzyme inhibition, but full reduction allows degradation by the intestinal enzyme trypsin.
• Allergenic properties as baker's eczema can be mitigated when ATIs are reduced by the thioredoxin/thioredoxin reductase system.
Higher structural disulphide bond reactivity of ATIs are linked to increased dough stiffness in bread dough processing. Fermentation conditions (yeast vs sour dough) and recipes (high pH in cakes/biscuits vs lower pH in bread) have an effect on the reactivity of thiol groups.
Here we propose to elucidate the role of redox status of ATIs on in vitro digestibility, intestinal cell binding, cell modulation and immunomodulation, and cereal bioprocessing. Different approaches to modify the disulphide bridges of ATIs in an isolated fraction and in situ during wheat food processing will be applied. The outcomes will be used to design clinical studies in which the pathological effects of partially reduced ATIs on the gut will be studied. The elucidation of this role will be pivotal to mitigate the pathological effects of ATIs to reduce consumer concerns and promote consumption of wheat-based food products.
The redox status of ATIs has been shown to be a switch knob for its biofunctionality in various ways:
o Enzyme inhibition can be promoted upon partial reduction. Despite inhibiting proteases at full reduction, ATIs become susceptible to proteolytic digestion: how does (partial) reduction improve or retard digestion ?
o what will be the impact of (partial) reduction on allergenic epitopes are they increased or degraded and how will these react in the gut ?
• How can the redox status during food processing actively be changed by food ingredients (reducing agents, baking soda) fermentation conditions (yeast vs sour dough) or redox enzymes ?
• What is the pathological impact of isolated and partially reduced ATIs in vivo ?
Proof of the effect of ATIs in the human gut will provide tools to improve the most important staple food by reducing the pathogenic properties and also in the work environment by using less allergenic wheat flour.
Deliverables of the research innovations and will filling of knowledge gaps:
Food bioprocessing protocols to reduce ATIs stability and bioactivity that take into account bread dough quality and industrial implementation.
First time the mode of pathological action of ATIs in relationship to their redox status will be investigated (in vitro and in vivo)
Proof of principle to mitigate pathological effects of ATIs via food bioprocessing
In depth knowledge on ATI isoform redox reactivity to help selection and breeding of favorable wheat varieties and/or development new desired varieties
Facts and not fiction for IBS, NGWS patients and patients with baker's asthma and eczema
This will result in the following deliverables per stakeholders
Deliverables to societal organisations
• Improved and scientific information about the role of ATIs in human pathology to experts in the field. Thus members and followers (3.5-5 million Dutch consumers) can be informed and advised proactively and less reactively:
o on the impact of ATIs and gluten containing products on human pathology, as it is now left to social media speculation
o on foods that can and cannot be tolerated after consumption, so consumers can make an informed choice. See also https://topsectoragrifood.nl/showcase-eten-we-onnodig-glutenvrij/
• Decreased expenditure on more expensive foods by consumers and less burden on the healthcare system, by increased food safety (i.e. refrain from certain foods that can cause pathologies)
Deliverables to international Cereal based product supply chain
• Development of ingredients to deliver ingredients to the bakery sector that mitigate ATI pathologies
• Appropriate processing methods/ingredients for manufacturers of cereal based products (bread, pastry, noodles, pasta, flat breads) to mitigate ATI
• More healthy wheat varieties available to the industrial partners and less baker's allergies
Deliverables to scientific partners
• Increased expertise on the fate of ATIs during food processing
• Increased expertise on the role of ATIs in human pathologies
• Information that can be used to breed wheat that is less pathogenic and more healthy for humans and animals, whilst more biotic stress/pest resistant