title: Plasma myeloperoxidase is inversely associated with endothelium-dependent vasodilation in elderly subjects with abnormal glucose metabolism.
abstract: Myeloperoxidase (MPO), a biomarker related to inflammation, oxidative stress, and nitric oxide scavenging, has been shown to impair endothelium-dependent vasodilation. Because elevated hydrogen peroxide concentrations in diabetic vessels may enhance MPO activity, we hypothesized that a stronger association of MPO with flow-mediated dilation (FMD) may be found in subjects with abnormal glucose metabolism. Myeloperoxidase concentrations were measured in EDTA plasma samples from participants of a population-based cohort study, including 230 subjects with normal glucose metabolism and 386 with abnormal glucose metabolism. Vascular function was expressed as FMD and nitroglycerin-mediated dilation of the brachial artery. In subjects with abnormal glucose metabolism, MPO was negatively associated with FMD (-20.9 [95% confidence interval {CI}, -41.7 to -0.2] -μm change in FMD per SD increment of MPO). This association remained significant after adjustment for nitroglycerin-mediated dilation (-31.1 [95% CI, -50.0 to -12.3]) and was not attenuated after further adjustment for established risk factors. In subjects with normal glucose metabolism, MPO was not significantly associated with FMD (2.0 [95% CI, -16.0 to 20.0]). In conclusion, in subjects with abnormal glucose metabolism, plasma levels of MPO are inversely associated with endothelium-dependent vasodilation, possibly reflecting enhancement of MPO activity by vascular oxidative stress.
authors.affiliation: Metabolic Laboratory, Department of Clinical Chemistry, VU University Medical Center, PO Box 7057, 1007MB Amsterdam, The Netherlands.
authors.forename: Leonard P
authors.initials: LP
authors.lastname: van der Zwan
authors.forename: Tom
authors.initials: T
authors.lastname: Teerlink
authors.forename: Jacqueline M
authors.initials: JM
authors.lastname: Dekker
authors.forename: Ronald M A
authors.initials: RM
authors.lastname: Henry
authors.forename: Coen D A
authors.initials: CD
authors.lastname: Stehouwer
authors.forename: Cornelis
authors.initials: C
authors.lastname: Jakobs
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Heine
authors.forename: Peter G
authors.initials: PG
authors.lastname: Scheffer
mesh_terms: D000368:Aged; D004730:Endothelium, Vascular / Q000201:enzymology* / Q000503:physiopathology; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009195:Peroxidase / Q000097:blood*; D014664:Vasodilation
chemical_list: D009195:Peroxidase; D005947:Glucose