title: Adipose gene expression profiles related to metabolic syndrome using microarray analyses in two different models.
abstract: BACKGROUND
  Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist has a wide-ranging influence on multiple components of metabolic syndrome. The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is a useful animal model of metabolic syndrome. To determine genes related to metabolic syndrome, we examined overlapping genes that are simultaneously decreased by PPAR-γ agonists and increased in OLETF rats using microarrays in two different models.
  
  
  METHODS
  In the first microarray analysis, PPAR-γ agonist-treated db/db mice were compared to standard diet-fed db/db mice. In the second microarray analysis, OLETF rats were compared to Long-Evans Tokushima Otsuka (LETO) rats (control of OLETF rats).
  
  
  RESULTS
  Among the overlapping genes, in the present study, we validated that lipocalin-2 expression was significantly decreased in the visceral adipose tissue of PPAR-γ agonist-treated db/db mice compared to standard diet-fed db/db mice and increased in OLETF rats compared to LETO rats using real time reverse transcription polymerase chain reaction. Furthermore, we showed for the first time that lipocalin-2 expression was significantly increased in the visceral adipose tissues of obese humans compared with nonobese humans. In addition, the expression level of lipocalin-2 in human visceral adipose tissue had a significant positive correlation with body mass index, serum interleukin-6, adipocyte fatty acid binding protein levels, and white blood cell count.
  
  
  CONCLUSIONS
  Lipocalin-2 was confirmed to be a significant adipokine affected by PPAR-γ agonist and obesity in the present study. Also, for the first time in human visceral adipose tissue, it was determined that the expression of lipocalin-2 from obese humans was significantly increased and correlated with circulating inflammatory markers.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Yoo
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hwan-Jin
authors.initials: HJ
authors.lastname: Hwang
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Tae Woo
authors.initials: TW
authors.lastname: Jung
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Ja Young
authors.initials: JY
authors.lastname: Ryu
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Ho Cheol
authors.initials: HC
authors.lastname: Hong
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Hae Yoon
authors.initials: HY
authors.lastname: Choi
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Sei Hyun
authors.initials: SH
authors.lastname: Baik
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea.
authors.forename: Kyung Mook
authors.initials: KM
authors.lastname: Choi
keywords: Lipocalin-2; Microarray; PPAR gamma