Detection of Two Types of Glycated Tryptophan Compounds in the Plasma of Chickens Fed Tryptophan Excess Diets

Abstract

When tryptophan is glycated with glucose, it results in forming two types of glycated tryptophan compounds, glucose-tryptophan Amadori product and (1R, 3S)-1-(D-gluco-1,2,3,4,5-pentahydroxypentyl)-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (PHP-THβC). As hyperglycemia and high body temperature are the characteristics in avian species, these are supposed to elevate the concentration of glycated tryptophan compounds in the plasma of chickens. However, there was no attempt to detect two types of glycated tryptophan compounds in the plasma of chickens, so far. Therefore, young chickens were fed tryptophan-excess diets (0, 1, 2 or 3% excess) for 14 days, and glycated tryptophan compounds were detected using a liquid chromatograph mass spectrometer (LC/MS). In the present study, two types of glycated tryptophan compounds, glucose-tryptophan Amadori product and PHP-THβC, were successfully detected in the plasma of chickens, and plasma levels of both glycated tryptophan compounds significantly correlated to plasma tryptophan concentration.

Keywords

• amadori product
• β-carboline
• chickens
• glycation
• tryptophan