title: Serum levels of fibroblast growth factor-21 are increased in chronic and acute renal dysfunction.
abstract: OBJECTIVE
  Fibroblast growth factor (FGF)-21 has recently been introduced as a circulating adipokine which reverses insulin resistance and obesity in rodents. In this study, regulation of FGF-21 in renal dysfunction was elucidated in both chronic kidney disease (CKD) and acute kidney dysfunction (AKD).
  
  
  METHODS
  Serum concentrations of total FGF-21 were quantified by enzyme-linked immunosorbent assay in 499 patients with CKD stages 1-5 (study population 1). Furthermore, total FGF-21 was determined before and within 30 h after unilateral nephrectomy, a model of AKD, in 32 patients (study population 2). FGF-21 levels were correlated to anthropometric and biochemical parameters of renal function, glucose and lipid metabolism, as well as inflammation, in both studies.
  
  
  RESULTS
  In study population 1, median [interquartile range] circulating FGF-21 adjusted for age, gender and body mass index was significantly different between CKD stages with highest values detectable in stage 5 (stage 1: 86·4 [132·9]; 2: 206·4 [223·1]; 3: 289·8 [409·3]; 4: 591·3 [789·0]; 5: 1918·1 [4157·0] ng/l). Furthermore, estimated glomerular filtration rate remained a strong independent and negative predictor of FGF-21. In study population 2, FGF-21 increased significantly postsurgically (325·0 [984·0] ng/l) as compared to presurgical values (255·5 [243·0] ng/l). Furthermore, relative changes of FGF-21 were independently and positively predicted by relative changes of creatinine.
  
  
  CONCLUSIONS
  We demonstrate that circulating FGF-21 is increased in both CKD and AKD. Our results suggest renal excretion as a major route for FGF-21 elimination. The pathophysiological significance of these findings needs to be elucidated in more detail.
authors.affiliation: Department of Endocrinology and Nephrology, University of Leipzig, Leipzig, Germany; IFB Adiposity Diseases, Leipzig University Medical Center, Leipzig, Germany.
authors.forename: Janka
authors.initials: J
authors.lastname: Hindricks
authors.forename: Thomas
authors.initials: T
authors.lastname: Ebert
authors.forename: Anette
authors.initials: A
authors.lastname: Bachmann
authors.forename: Susan
authors.initials: S
authors.lastname: Kralisch
authors.forename: Ulrike
authors.initials: U
authors.lastname: Lössner
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kratzsch
authors.forename: Jens-Uwe
authors.initials: JU
authors.lastname: Stolzenburg
authors.forename: Anja
authors.initials: A
authors.lastname: Dietel
authors.forename: Joachim
authors.initials: J
authors.lastname: Beige
authors.forename: Matthias
authors.initials: M
authors.lastname: Anders
authors.forename: Ingolf
authors.initials: I
authors.lastname: Bast
authors.forename: Matthias
authors.initials: M
authors.lastname: Blüher
authors.forename: Michael
authors.initials: M
authors.lastname: Stumvoll
authors.forename: Mathias
authors.initials: M
authors.lastname: Fasshauer
mesh_terms: D000328:Adult; D000368:Aged; D000886:Anthropometry; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005346:Fibroblast Growth Factors / Q000097:blood*; D005919:Glomerular Filtration Rate; D006801:Humans; D007333:Insulin Resistance; D050356:Lipid Metabolism; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy; D051437:Renal Insufficiency / Q000097:blood*; D051436:Renal Insufficiency, Chronic / Q000097:blood*; D016896:Treatment Outcome
chemical_list: C414620:fibroblast growth factor 21; D005346:Fibroblast Growth Factors