Methylglyoxal augments intracellular oxidative stress in human aortic endothelial cells.
Methylglyoxal (MGO) is a non-enzymatic metabolite in the glycolytic pathway and its concentration in blood and tissues is elevated in diabetes and renal failure. MGO induces tissue injuries via ROS; however, the mechanism remains to be clarified. The present study examined the harmful actions of MGO. Human aortic endothelial cells were assessed under real-time fluorescent microscopy with continuous superfusion. Increases in intracellular ROS were measured with fluorescent indicator, 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate acetyl ester (DCFH-DA). The addition of MGO rapidly increased the ROS in a dose-dependent manner. The increment of DCF was entirely abolished by pre-treatment with superoxide anion scavenger and membrane-permeable catalase, indicating that MGO induces superoxide production. The increment was completely inhibited by 2-thenoyltrifluoroacetone or carbonyl cyanide 3-chlorophenylhydrazone and partially inhibited by N-methyl-L-arginine. These data suggest that MGO stimulates superoxide production from mitochondria and partially stimulates nitric oxide synthase in human endothelial cells.
Miyazawa
Noriko
N
Tohoku University Hospital, Division of Nephrology, Endocrinology and Vascular Medicine, Sendai, Miyagi, 980-8574, Japan.
Abe
Michiaki
M
Souma
Tomokazu
T
Tanemoto
Masayuki
M
Abe
Takaaki
T
Nakayama
Masaaki
M
Ito
Sadayoshi
S
D001011:Aorta / Q000187:drug effects* / Q000378:metabolism; D002474:Cell-Free System / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D005452:Fluoresceins / Q000493:pharmacokinetics; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects*; D011765:Pyruvaldehyde / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000493:pharmacokinetics; D015854:Up-Regulation / Q000187:drug effects
C110400:2',7'-dichlorodihydrofluorescein diacetate; D005452:Fluoresceins; D016877:Oxidants; D017382:Reactive Oxygen Species; D011765:Pyruvaldehyde; D019001:Nitric Oxide Synthase