Quantification of peptides causing celiac disease in historical and modern hard red spring wheat cultivars

Authors: MALALGODA, MANEKA - North Dakota State University; Ohm, Jae-Bom; MEINHARDT, STEVEN - North Dakota State University; SIMSEK, SENAY - North Dakota Department Of Agriculture

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/7/2016
Publication Date: 10/20/2016
Citation: Malalgoda, M., Ohm, J., Meinhardt, S., Simsek, S. 2016. Quantification of peptides causing celiac disease in historical and modern hard red spring wheat cultivars. American Association of Cereal Chemists International, October 23-26, 2016, Savannah, GA. http://www.aaccnet.org/meetings/Documents/2016Abstracts/aacc2016abs157.htm.

Interpretive Summary:

Technical Abstract: Celiac disease (CD) is prevalent in 0.5 to 1.26% of adolescents and adults. The disease develops in genetically susceptible individuals as a result of ingestion of gluten forming proteins found in cereals such as, wheat (Triticum aestivum L.), rye (Secale cereale L.) and barley (Hordeum sativum L.). Gluten is composed of glutenin and gliadin proteins. Gliadins are further divided into a-/ß-, '- and '- gliadins. Studies suggest that the majority of toxic/ immunogenic peptides are produced by a-gliadin proteins. It is unknown if all wheat cultivars cause the same reaction or if the intensity of the reaction is dependent on the type of wheat ingested. There are claims that breeding practices have changed wheat protein chemistry over the years, and this has resulted in modern wheat being more toxic in terms of CD as opposed to historical wheat. In this context, the aim of the study was to detect and quantify celiac-disease-initiating peptides of the gliadin proteins in historical and modern hard red spring wheat cultivars released in North Dakota during the last 110 years. For this purpose, gliadin proteins were extracted from wheat and then used in untargeted mass spectrometric analysis to determine the presence or absence of immunogenic peptides. For comparison of toxicity between historical and modern wheat cultivars, a targeted approach was used, where the relative amount of toxic/ immunogenic peptides was determined using heavy labelled peptides. The relative amount of toxic/ immunogenic peptides was different between the wheat cultivars. However, the results indicate that immunogenic peptides causing CD are detected in both historical and modern spring wheat cultivars irrespective of release year, and there may not be a difference in terms of CD toxicity between historical and modern hard red spring wheat cultivars.