Chemistry and biological effects of melanoidins and glyceraldehyde-derived pyridinium as advanced glycation end products.
Blue pigments (blue-M1 and blue-M2) and red pigments (red-M1 and red-M2) were generated in a xylose-glycine reaction system. Blue-M2 was identified as an addition compound of di-xylulose-glycine to blue-M1 that involved two pyrrolopyrrole structures. We identified red pigments as isomers of addition compounds of xylulose-glycine to the condensed compound between pyrrolopyrrole-2-carbaldehyde and pyrrole-2-carbaldehyde. These pigments have polymerizing activity, suggesting that they are important Maillard reaction intermediates through the formation of melanoidins. Melanoidins induced IFN-gamma and IL-12 expression in spleen cells exposed to allergen and in macrophages, respectively. These findings suggest that melanoidins have a suppressive effect on allergic reaction as a novel physiological effect. On the other hand, we identified a glyceraldehyde-derived advanced glycation end product (AGE) formed from glyceraldehyde and N-acetylarginine as well as glyceraldehyde-derived pyridinium (GLAP) in physiological conditions. The AGE was identified as 5-methylimidazoline-4-one (MG-H1), which has been reported to be formed from arginine and methylglyoxal. GLAP, which induced reactive oxygen species (ROS) production in HL-60 cells, is supposed to be a toxic AGE, while MG-H1 is a nontoxic AGE.
Hayase
Fumitaka
F
Meiji University, Department of Agricultural Chemistry, Higashi-mita, Kawasaki, Kanagawa 214-8571, Japan. fumi@isc.meiji.ac.jp
Usui
Teruyuki
T
Nishiyama
Kazuyuki
K
Sasaki
Shigeyuki
S
Shirahashi
Yoshinobu
Y
Tsuchiya
Naoyuki
N
Numata
Naoko
N
Watanabe
Hirohito
H
D017127:Glycation End Products, Advanced / Q000737:chemistry*; D005985:Glyceraldehyde; D005998:Glycine; D018922:HL-60 Cells; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects; D011108:Polymers / Q000737:chemistry* / Q000494:pharmacology; D011726:Pyridinium Compounds; D017382:Reactive Oxygen Species; D014994:Xylose
D017127:Glycation End Products, Advanced; D011108:Polymers; D011726:Pyridinium Compounds; D017382:Reactive Oxygen Species; C011908:melanoidin polymers; D005985:Glyceraldehyde; D014994:Xylose; D005998:Glycine