title: Circulating irisin and glucose-dependent insulinotropic peptide are associated with the development of polycystic ovary syndrome.
abstract: BACKGROUND
  Polycystic ovary syndrome (PCOS) is characterized by oligo- or anovulation, polycystic ovary, and/or hyperandrogenism. In addition, many PCOS patients present with dyslipidemia, insulin resistance, and obesity. Due to the complexity of this disorder, the causes of PCOS remain to be identified.
  
  
  OBJECTIVE
  Because many PCOS patients have a propensity to develop dyslipidemia, we hypothesized that the brown adipose-differentiation factor, irisin, and the glucose-dependent insulinotropic peptide (GIP) play a role in the development of PCOS.
  
  
  METHODS
  Serum hormone levels in 202 PCOS patients and 47 healthy women were investigated.
  
  
  METHODS
  Patients were stratified based on the presence/absence of metabolic syndrome risk factors, as defined by the National Cholesterol Education Program's Adult Treatment Panel III report (ATPIII [+] and ATPIII [-]), or body mass index (healthy-weight and overweight).
  
  
  METHODS
  We measured serum irisin, GIP, LH, anti-Mullerian hormone (AMH), and androgens as well as metabolic indices including homeostasis model assessment-insulin resistance, Matsuda's sensitivity index, and quantitative insulin-sensitivity check index.
  
  
  RESULTS
  PCOS patients exhibited hyperandrogenism, dyslipidemia, and hyperinsulinism, as well as elevated LH and AMH levels. In addition, fasting irisin level (P < .001) and glucose-induced GIP response (P = .013) in PCOS patients were significantly elevated as compared to those of control women. Remarkably, levels of fasting irisin and glucose-induced GIP response remained significantly elevated in ATP III [-] PCOS and healthy-weight PCOS patients when compared to matched controls. Analysis of the effect size indicated that both fasting irisin and glucose-induced GIP response are significant risk factors for PCOS with odds ratios of 6.63 and 4.21, respectively.
  
  
  CONCLUSIONS
  Although there is as yet no evidence for a causal link between irisin and/or GIP and PCOS, it is conceivable that irisin and GIP might contribute to the development of PCOS and may also represent novel PCOS biomarkers.
authors.affiliation: Department of Obstetrics and Gynecology (C.L.C., S.Y.H., Y.K.S., P.J.C., C.-J.W., I.T.L.), Chang Gung Memorial Hospital Linkou Medical Center, Chang Gung University, 5 Fu-Shin Street, Kweishan, Taoyuan, Taiwan 333.
authors.forename: Chia Lin
authors.initials: CL
authors.lastname: Chang
authors.forename: Shang Yu
authors.initials: SY
authors.lastname: Huang
authors.forename: Yung Kuei
authors.initials: YK
authors.lastname: Soong
authors.forename: Po Jen
authors.initials: PJ
authors.lastname: Cheng
authors.forename: Chin-Jung
authors.initials: CJ
authors.lastname: Wang
authors.forename: I Ting
authors.initials: IT
authors.lastname: Liang
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D005260:Female; D005353:Fibronectins / Q000097:blood*; D005749:Gastric Inhibitory Polypeptide / Q000097:blood*; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D011085:Polycystic Ovary Syndrome / Q000097:blood*; D011237:Predictive Value of Tests; D018570:Risk Assessment; D055815:Young Adult
chemical_list: D015415:Biomarkers; C577593:FNDC5 protein, human; D005353:Fibronectins; D005749:Gastric Inhibitory Polypeptide