title: GlycA, a biomarker of inflammatory glycoproteins, is more closely related to the leptin/adiponectin ratio than to glucose tolerance status.
abstract: OBJECTIVE
  Plasma GlycA is a recently developed biomarker whose nuclear magnetic resonance signal originates from glycosylated acute-phase proteins. The aim of our study was to determine potential relationships between GlycA and adiposity, insulin resistance (HOMA(ir)), high sensitive C-reactive protein (hs-CRP), leptin, adiponectin, and the leptin/adiponectin ratio, and to test whether GlycA is elevated in subjects with impaired fasting glucose (IFG) and type 2 diabetes mellitus (T2DM).
  
  
  METHODS
  Plasma GlycA, hs-CRP, leptin, adiponectin, the leptin/adiponectin ratio, and insulin resistance (HOMA(ir)) were measured in 103 fasting subjects (30 with normal fasting glucose, 25 with IFG and 48 with T2DM).
  
  
  RESULTS
  In all subjects combined, plasma GlycA was correlated positively with body mass index (BMI), HOMA(ir), hs-CRP, leptin and the leptin/adiponectin ratio, and inversely with adiponectin (p < 0.05 to p < 0.001). GlycA did not significantly vary according to glucose tolerance category (p = 0.060). GlycA was related positively to the leptin/adiponectin ratio (p = 0.049), independent of BMI (p = 0.056) and HOMA(ir) (p = 0.50).
  
  
  CONCLUSIONS
  High plasma GlycA reflects a pro-inflammatory state. Adipose tissue-associated inflammatory processes could contribute to increased circulating levels of glycosylated acute-phase proteins.
authors.affiliation: Department of Endocrinology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands. Electronic address: r.p.f.dullaart@int.umcg.nl.
authors.forename: Robin P F
authors.initials: RP
authors.lastname: Dullaart
authors.affiliation: Department of Endocrinology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Eke G
authors.initials: EG
authors.lastname: Gruppen
authors.affiliation: LabCorp, Raleigh, NC, USA.
authors.forename: Margery A
authors.initials: MA
authors.lastname: Connelly
authors.affiliation: LabCorp, Raleigh, NC, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Otvos
authors.affiliation: Department of Vascular Medicine, University of Groningen, University Medical Center Groningen, The Netherlands.
authors.forename: Joop D
authors.initials: JD
authors.lastname: Lefrandt
mesh_terms: D052242:Adiponectin / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006031:Glycosylation; D006801:Humans; D007249:Inflammation / Q000097:blood; D020738:Leptin / Q000097:blood*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D019906:Nuclear Magnetic Resonance, Biomolecular
chemical_list: D052242:Adiponectin; D015415:Biomarkers; D001786:Blood Glucose; D006023:Glycoproteins; D020738:Leptin; D002097:C-Reactive Protein
keywords: C-reactive protein; Diabetes mellitus; Glycoproteins; Leptin/adiponectin ratio; Nuclear magnetic resonance spectroscopy