Gluten exorphins are a group of opioid peptides formed during the

digestion Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intest ...

of the

gluten Gluten is a structural protein naturally found in certain cereal grains. Although "gluten" often only refers to wheat proteins, in medical literature it refers to the combination of prolamin and glutelin proteins naturally occurring in all grai ...

protein. These peptides work as external regulators for gastrointestinal movement and hormonal release. The breakdown of gliadin, a polymer of wheat proteins, creates amino acids that stop the gluten epitopes from entering the immune system to activate inflammatory reactions. During this process, gluten does not fully break down, thus increasing the presence of gluten exorphins. Because of this, researchers think this is what might lead to various diseases. Research shows the benefits of gluten- and casein-free diets for people with diseases and disorders connected to gluten exorphins. The mechanism behind this is still unknown. There is a possibility that gluten has deleterious effects on the human digestive system. When people are more susceptible to gluten and casein allergies, the weakened intestinal lining allows gluten exorphin to flow.

Categorization

There are four known gluten exorphins with known structure:

Gluten exorphin A5

*Structure: H-Gly-Tyr-Tyr-Pro-Thr-OH *Chemical formula: C₂₄H₃₇N₅O₉ *Molecular weight: 599.64 g/mol

Gluten exorphin B4

*Structure: H-Tyr-Gly-Gly-Trp-OH *Chemical formula: C₂₄H₂₇N₅O₆ *Molecular weight: 481.50 g/mol

Gluten exorphin B5

*Structure: H-Tyr-Gly-Gly-Trp-Leu-OH *Chemical formula: C₃₀H₃₈N₆O₇ *Molecular weight: 594.66 g/mol

Gluten exorphin C

*Structure: H-Tyr-Pro-Ile-Ser-Leu-OH *Chemical formula: C₂₉H₄₅N₅O₈ *Molecular weight: 591.70 g/mol

Clinical significance

Recent research surrounding gluten exorphins has revolved around how the peptides might play a role in various diseases and disorders.

Celiac disease

In response to gluten, people with celiac disease will release gluten exorphins as part of the allergic immune response. Due to the weakening of intestinal walls caused by celiac disease, some of these gluten exorphins can make their way through the lining of the intestines and are then absorbed into the bloodstream.

References

Opioid peptides Tetrapeptides Pentapeptides {{biochem-stub