title: The effects of obesity and polycystic ovary syndrome on serum lipocalin-2 levels: a cross-sectional study.
abstract: BACKGROUND
  Lipocalin-2 is a novel adipokine that appears to play a role in the development of insulin resistance. Serum lipocalin-2 levels are elevated in obese patients. Obesity and insulin resistance are cardinal characteristics of the polycystic ovary syndrome (PCOS). However, there are limited data on serum lipocalin-2 levels in patients with PCOS. The aim of the present study was to assess serum lipocalin-2 levels in PCOS.
  
  
  METHODS
  We studied 200 patients with PCOS and 50 healthy female volunteers.
  
  
  RESULTS
  Serum lipocalin-2 levels were slightly higher in women with PCOS compared with controls (65.4 +/- 34.3 vs. 60.3 +/- 26.0 ng/ml, respectively) but this difference did not reach statistical significance. In contrast, lipocalin-2 levels were higher in overweight/obese women with PCOS than in normal weight women with the syndrome (76.2 +/- 37.3 vs. 54.5 +/- 27.2 ng/ml, respectively; p < 0.001). Serum lipocalin-2 levels were also higher in overweight/obese controls compared with normal weight controls (70.1 +/- 24.9 vs. 50.5 +/- 23.7 ng/ml, respectively; p = 0.004). In the total study population (patients with PCOS and controls), lipocalin-2 levels were independently correlated with the body mass index (p < 0.001). In women with PCOS, lipocalin-2 levels were independently correlated with the waist (p < 0.001).
  
  
  CONCLUSIONS
  Obesity is associated with elevated serum lipocalin-2 levels. In contrast, PCOS does not appear to affect lipocalin-2 levels.
authors.affiliation: Division of Endocrinology and Human Reproduction, Second Department of Obstetrics and Gynecology, Aristotle University of Thessaloniki, Hippokration Hospital, Thessaloniki, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Panidis
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Tziomalos
authors.forename: Ekaterini
authors.initials: E
authors.lastname: Koiou
authors.forename: Eleni A
authors.initials: EA
authors.lastname: Kandaraki
authors.forename: Elena
authors.initials: E
authors.lastname: Tsourdi
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Delkos
authors.forename: Emmanuil
authors.initials: E
authors.lastname: Kalaitzakis
authors.forename: Ilias
authors.initials: I
authors.lastname: Katsikis
mesh_terms: D000209:Acute-Phase Proteins; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood*; D009765:Obesity / Q000097:blood* / Q000150:complications; D050177:Overweight / Q000097:blood; D011085:Polycystic Ovary Syndrome / Q000097:blood* / Q000150:complications; D011518:Proto-Oncogene Proteins / Q000097:blood*
chemical_list: D000209:Acute-Phase Proteins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins