title: Serum adipokines as biomarkers of beta-cell function in patients with type 1 diabetes: positive association with leptin and resistin and negative association with adiponectin.
abstract: BACKGROUND
  We investigated the adipokines adiponectin, leptin and resistin as serum biomarkers of beta-cell function in patients with type 1 diabetes.
  
  
  METHODS
  One hundred and eighteen patients with type 1 diabetes (20.3 ± 7.5 years) diagnosed <5 years underwent standardized mixed meal test (MMTT) for 2 h. Systemic concentrations of C-peptide, adiponectin, leptin and resistin obtained during MMTT were measured and compared between patient groups by multiple regression analysis.
  
  
  RESULTS
  Patients were divided by their adipokine levels in subgroups above or below the median level ('high versus low'). High adiponectin levels (>10.6 µg/mL) were associated with lower C-peptide compared to the low adiponectin subgroup (p < 0.03). Increased leptin or resistin concentrations associated positively with beta-cell function even after adjustment for metabolic confounders (p < 0.04). The described associations between adipokines and C-peptide concentrations persisted in Spearman correlation tests (p < 0.05). Serum adipokines fell during MMTT (p < 0.05).
  
  
  CONCLUSIONS
  Serum adipokine levels differentially correlate with beta-cell function in type 1 diabetes independent of BMI or metabolic control. Serum adipokines should be investigated as biomarkers of beta-cell function in prospective studies and intervention trials in type 1 diabetes.
authors.affiliation: Institute for Clinical Diabetology at German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University, Düsseldorf, Germany. mnpham@gmx.de
authors.forename: Minh Nguyet
authors.initials: MN
authors.lastname: Pham
authors.forename: Hubert
authors.initials: H
authors.lastname: Kolb
authors.forename: Thomas
authors.initials: T
authors.lastname: Mandrup-Poulsen
authors.forename: Tadej
authors.initials: T
authors.lastname: Battelino
authors.forename: Johnny
authors.initials: J
authors.lastname: Ludvigsson
authors.forename: Paolo
authors.initials: P
authors.lastname: Pozzilli
authors.forename: Michael
authors.initials: M
authors.lastname: Roden
authors.forename: Nanette C
authors.initials: NC
authors.lastname: Schloot
mesh_terms: D052242:Adiponectin / Q000097:blood*; D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood*; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005215:Fasting; D005260:Female; D006801:Humans; D050417:Insulin-Secreting Cells / Q000502:physiology*; D020738:Leptin / Q000097:blood*; D008297:Male; D062407:Meals; D052243:Resistin / Q000097:blood*
chemical_list: D052242:Adiponectin; D015415:Biomarkers; D002096:C-Peptide; D020738:Leptin; D052243:Resistin