Address for correspondence: David R. Sell, Ph.D., Department of Pathology, Case Western Reserve University, Wolstein Research Bldg.-Room 5144, 2103 Cornell Road, Cleveland, OH 44106-7288. Voice: +1-216-368-2930; fax: +1-216-368-1357. drs7{at}po.cwru.edu
The
-amino group of lysyl residues oxidatively deaminates in
the presence of
-dicarbonyl sugars and redox-active metals forming
-aminoadipic acid-
-semialdehyde (allysine; Suyama's hypothesis),
which can further oxidize into 2-aminoadipic acid. Here we show
that 2-aminoadipic acid is significantly (
P < 0.05) correlated
with 6-hydroxynorleucine, carboxyethyllysine (CEL), and carboxymethyllysine
(CML) in human skin collagen. Since CEL and CML can originate
from carbohydrate and lipid by oxidative decomposition and
-dicarbonyl
formation, these results provide support for Suyama's hypothesis.
Allysine, in turn, is readily converted by oxidation into 2-aminoadipic
acid, which accumulates to high levels in skin (i.e., > 2
nmol/mg collagen).
-Dicarbonyls