Heat-shock protein 27 is a major methylglyoxal-modified protein in endothelial cells.
In endothelial cells cultured under high glucose conditions, methylglyoxal is the major intracellular precursor in the formation of advanced glycation endproducts. We found that endothelial cells incubated with 30 mM d-glucose produced approximately 2-fold higher levels of methylglyoxal but not 3-deoxyglucosone and glyoxal, as compared to 5 mM d-glucose. Under hyperglycaemic conditions, the methylglyoxal-arginine adduct argpyrimidine as detected with a specific antibody, but not N(e)-(carboxymethyl)lysine and N(e)-(carboxyethyl)lysine, was significantly elevated. The glyoxylase I inhibitor HCCG and the PPARgamma ligand troglitazone also increased argpyrimidine levels. Increased levels of argpyrimidine by glucose, HCCG and troglitazone are accompanied by a decrease in proliferation of endothelial cells. A 27 kDa protein was detected as a major argpyrimidine-modified protein. With in-gel digestion and mass spectrometric analysis, we identified this major protein as heat-shock protein 27 (Hsp27). This argpyrimidine modification of Hsp27 may contribute to changes in endothelial cell function associated to diabetes.
Department of Clinical Chemistry, Vrije Universiteit Medical Center, Amsterdam, The Netherlands. c.schalkwijk@intmed.unimaas.nl
Casper G
CG
Schalkwijk
Jan
J
van Bezu
Roel C
RC
van der Schors
Koji
K
Uchida
Coen D A
CD
Stehouwer
Victor W M
VW
van Hinsbergh
D002478:Cells, Cultured; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D005978:Glutathione / Q000031:analogs & derivatives / Q000494:pharmacology; D017127:Glycation End Products, Advanced / Q000096:biosynthesis; D055551:HSP27 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D007791:Lactoylglutathione Lyase / Q000037:antagonists & inhibitors; D018832:Molecular Chaperones; D009363:Neoplasm Proteins / Q000032:analysis / Q000378:metabolism*; D009952:Ornithine / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D011743:Pyrimidines / Q000032:analysis / Q000378:metabolism*; D011765:Pyruvaldehyde / Q000378:metabolism*
D017127:Glycation End Products, Advanced; D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D009363:Neoplasm Proteins; D011743:Pyrimidines; C111218:S-(N-hydroxy-N-(4-chlorophenyl)carbamoyl)glutathione diethyl ester; C107313:argpyrimidine; D011765:Pyruvaldehyde; D009952:Ornithine; D007791:Lactoylglutathione Lyase; D005978:Glutathione; D005947:Glucose