title: Glucose scavenging of nitric oxide.
abstract: Endothelial dysfunction accompanies suboptimal glucose control in patients with diabetes mellitus. A hallmark of endothelial dysfunction is a deficiency in production or bioavailability of vascular nitric oxide (NO). Here we demonstrate that acute exposure of human endothelial cells to glucose, at levels found in plasma of diabetic patients, results in a significant blunting of NO responses to the endothelial nitric oxide synthase (eNOS) agonists bradykinin and A-23187. Monitoring of NO generation by purified recombinant bovine eNOS in vitro, using amperometric electrochemical detection and an NO-selective porphyrinic microelectrode, showed that glucose causes a progressive and concentration-dependent attenuation of detectable NO. Addition of glucose to pure NO solutions similarly elicited a sharp decrease in NO concentration, indicating that glucose promotes NO loss. Electrospray ionization-tandem mass spectrometry, using negative ion monitoring, directly demonstrated the occurrence of a covalent reaction involving unitary addition of NO (or a derived species) to glucose. Collectively, our findings reveal that hyperglycemia promotes the chemical inactivation of NO; this glucose-mediated NO loss may directly contribute to hypertension and endothelial dysfunction in diabetic patients.
authors.affiliation: Program in Biomedical Engineering, Department of Medicine, State University of New York, Stony Brook, NY 11794-8152, USA.
authors.forename: S V
authors.initials: SV
authors.lastname: Brodsky
authors.forename: A M
authors.initials: AM
authors.lastname: Morrishow
authors.forename: N
authors.initials: N
authors.lastname: Dharia
authors.forename: S S
authors.initials: SS
authors.lastname: Gross
authors.forename: M S
authors.initials: MS
authors.lastname: Goligorsky
mesh_terms: D000143:Acids / Q000378:metabolism; D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002417:Cattle; D002461:Cell Line, Transformed; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D007476:Ionophores / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III; D051381:Rats; D011994:Recombinant Proteins; D012077:Renal Artery / Q000166:cytology / Q000378:metabolism; D012977:Sodium Nitrite / Q000494:pharmacology; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000143:Acids; D007476:Ionophores; D011994:Recombinant Proteins; D009569:Nitric Oxide; D000001:Calcimycin; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D005947:Glucose; D012977:Sodium Nitrite; D001920:Bradykinin