Glycated Tryptophan PHP-TH beta C Incorporated into Various Chicken Embryonic Cells Constitutes Cellular Proteins

Glycation is a non-enzymatic reaction, and amino acids are glycated by glucose in vivo. Tryptophan is glycated with glucose to form two types of glycated compounds, tryptophan-Amadori product and (1R, 3S)-1-(D-gluco-1, 2, 3, 4, 5-pentahydroxypentyl)-1, 2, 3, 4-tetrahydro-beta-carboline-3-carboxylic acid (PHP-TH beta C). Although PHP-TH beta C can be incorporated into various chicken embryonic cells, the mechanism of its incorporation into intracellular fluids has not been clarified. In this study, we examined whether PHP-TH beta C once incorporated into various chicken embryonic cells can combine with proteins. Embryonic cells from the breast muscle, liver, spleen, kidney, proventriculus, gizzard, and skin were prepared and 3H-PHP-TH beta C was added to the culture medium at final concentrations of 0, 200, 400, 600, and 800 mu M to examine the incorporation of PHP-TH beta C. After 18 h of incubation, radioactivity was measured in the whole-cell and protein fractions of the chicken embryonic cells. As PHP-TH beta C concentration increased from 0 to 600 mu M, its accumulation in the whole-cell fractions of all types of chicken embryonic cells linearly increased and reached the maximum level. The saturated PHP-TH beta C accumulation in the whole-cell fractions suggests that PHP-TH beta C could be incorporated into intracellular fluids across cellular membranes by some transporter proteins. As PHP-TH beta C concentration increased from 0 to 800 mu M, its accumulation in the protein fractions of all types of chicken embryonic cells increased in a linear manner and reached a maximum level in the 800 mu M PHPTH beta C treatment group. This is the first study to indicate that a part of PHP-TH beta C incorporated into the whole-cell fraction was detected in the protein fraction of various chicken embryonic cells.