title: Uncarboxylated matrix Gla protein (ucMGP) is associated with coronary artery calcification in haemodialysis patients.
abstract: Matrix gamma-carboxyglutamate (Gla) protein (MGP) is a potent local inhibitor of cardiovascular calcification and accumulates at areas of calcification in its uncarboxylated form (ucMGP). We previously found significantly lower circulating ucMGP levels in patients with a high vascular calcification burden. Here we report on the potential of circulating ucMGP to serve as a biomarker for vascular calcification in haemodialysis (HD) patients. Circulating ucMGP levels were measured with an ELISA-based assay in 40 HD patients who underwent multi-slice computed tomography (MSCT) scanning to quantify the extent of coronary artery calcification (CAC). The mean ucMGP level in HD patients (193 +/- 65 nM) was significantly lower as compared to apparently healthy subjects of the same age (441 +/- 97 nM; p < 0.001) and patients with rheumatoid arthritis (RA) without CAC (560 +/- 140 nM; p < 0.001). Additionally, ucMGP levels correlated inversely with CAC scores (r = -0.41; p = 0.009), and this correlation persisted after adjustment for age, dialysis vintage and high-sensitivity C-reactive protein (hs-CRP). Since circulating ucMGP levels are significantly and inversely correlated with the extent of CAC in HD patients, ucMGP may become a tool for identifying HD patients with a high probability of cardiovascular calcification.
authors.affiliation: Department of Biochemistry, Maastricht University, PO Box 616, 6200 MD Maastricht, The Netherlands.
authors.forename: Ellen C M
authors.initials: EC
authors.lastname: Cranenburg
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Brandenburg
authors.forename: Cees
authors.initials: C
authors.lastname: Vermeer
authors.forename: Melanie
authors.initials: M
authors.lastname: Stenger
authors.forename: Georg
authors.initials: G
authors.lastname: Mühlenbruch
authors.forename: Andreas H
authors.initials: AH
authors.lastname: Mahnken
authors.forename: Ulrich
authors.initials: U
authors.lastname: Gladziwa
authors.forename: Markus
authors.initials: M
authors.lastname: Ketteler
authors.forename: Leon J
authors.initials: LJ
authors.lastname: Schurgers
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002114:Calcinosis / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging; D002135:Calcium-Binding Proteins / Q000097:blood*; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000097:blood* / Q000150:complications / Q000000981:diagnostic imaging; D003430:Cross-Sectional Studies; D015536:Down-Regulation; D004797:Enzyme-Linked Immunosorbent Assay; D016326:Extracellular Matrix Proteins / Q000097:blood*; D005260:Female; D005858:Germany; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D011237:Predictive Value of Tests; D011499:Protein Processing, Post-Translational; D006435:Renal Dialysis; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed; D000097568:Matrix Gla Protein
chemical_list: D015415:Biomarkers; D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; D000097568:Matrix Gla Protein