Barley Enzymes Effectively Digest Gluten in Rats

Celiac.com 09/12/2006 – A recent study by researchers at Stanford University has found that barley endoprotease EP-B2 is effective at digesting gluten in rats, and should be studied further as an “adjunct to diet control” in human celiac disease patients. This new finding adds to Stanford’s Open Original Shared Link on enzyme therapy as a possible treatment for those with celiac disease, and may one day lead to a effective treatment.

"Celiac Sprue is a multi-factorial disease characterized by an intestinal inflammatory response to ingested gluten. Proteolytically resistant gluten peptides from wheat, rye and barley persist in the intestinal lumen, and elicit an immune response in genetically susceptible individuals. Here we demonstrate the in vivo ability of a gluten-digesting protease ("glutenase") to accelerate the breakdown of a gluten-rich solid meal. The proenzyme form of endoprotease B, isoform 2 from Hordeum vulgare (EP-B2) was orally administered to adult rats with a solid meal containing 1 g gluten. Gluten digestion in the stomach and small intestine was monitored as a function of enzyme dose and time by HPLC and mass spectrometry. In the absence of supplementary EP-B2, gluten was solubilized and proteolyzed to a limited extent in the stomach, and was hydrolyzed and assimilated mostly in the small intestine. In contrast, EP-B2 was remarkably effective at digesting gluten in the rat stomach in a dose and time dependent fashion. At a 1:25 EP-B2:gluten dose, the gastric concentration of the highly immunogenic 33-mer gliadin peptide reduced by more than 50-fold within 90 min, with no overt signs of toxicity. Evaluation of EP-B2 as an adjunct to diet control is therefore warranted in celiac patients."