title: Effects of weight loss and exercise on apelin serum concentrations and adipose tissue expression in human obesity.
abstract: OBJECTIVE
  Apelin is an adipokine which plays a role in the regulation of glucose homeostasis and may contribute to the link between increased adipose tissue mass and obesity related metabolic diseases. Here we investigate the role of omental and subcutaneous (SC) adipose tissue apelin and its receptor APJ mRNA expression in human obesity and test the hypothesis that changes in circulating apelin are associated with reduced fat mass in three weight loss intervention studies.
  
  
  METHODS
  Apelin serum concentration was measured in 740 individuals in a cross-sectional (n = 629) study including a subgroup (n = 161) for which omental and SC apelin mRNA expression has been analyzed and in three interventions: 12 weeks exercise (n = 60), 6 months calorie-restricted diet (n = 19), 12 months after bariatric surgery (n = 32).
  
  
  RESULTS
  Apelin mRNA is significantly higher expressed in adipose tissue of patients with type 2 diabetes and correlates with circulating apelin, BMI, body fat, C-reactive protein, and insulin sensitivity. Obesity surgery-induced weight loss causes a significant reduction in omental and SC apelin expression. All interventions led to significantly reduced apelin serum concentrations which significantly correlate with improved insulin sensitivity, independently of changes in BMI.
  
  
  CONCLUSIONS
  Reduced apelin expression and serum concentration may contribute to improved insulin sensitivity beyond significant weight loss.
authors: Department of Medicine, University of Leipzig, Leipzig, Germany.
authors: Joanna
authors: J
authors: Krist
authors: Katharina
authors: K
authors: Wieder
authors: Nora
authors: N
authors: Klöting
authors: Andreas
authors: A
authors: Oberbach
authors: Susan
authors: S
authors: Kralisch
authors: Tobias
authors: T
authors: Wiesner
authors: Michael R
authors: MR
authors: Schön
authors: Daniel
authors: D
authors: Gärtner
authors: Arne
authors: A
authors: Dietrich
authors: Edward
authors: E
authors: Shang
authors: Tobias
authors: T
authors: Lohmann
authors: Miriam
authors: M
authors: Dreßler
authors: Mathias
authors: M
authors: Fasshauer
authors: Michael
authors: M
authors: Stumvoll
authors: Matthias
authors: M
authors: Blüher
mesh_terms: D050154:Adiposity; D000328:Adult; D000073861:Apelin; D000075244:Apelin Receptors; D050110:Bariatric Surgery; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D031204:Caloric Restriction; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood; D015536:Down-Regulation; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood* / Q000235:genetics; D050152:Intra-Abdominal Fat / Q000378:metabolism*; D016018:Least-Squares Analysis; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D009765:Obesity / Q000097:blood / Q000235:genetics / Q000503:physiopathology / Q000628:therapy*; D011446:Prospective Studies; D012333:RNA, Messenger / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000097:blood; D050151:Subcutaneous Fat / Q000378:metabolism*; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss
chemical_list: C115436:APLN protein, human; C104575:APLNR protein, human; D000073861:Apelin; D000075244:Apelin Receptors; D001786:Blood Glucose; D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled