title: Serum soluble α-klotho in hemodialysis patients.
abstract: BACKGROUND
  The extracellular domain of klotho is cleaved and released into various extracellular fluids, such as blood, urine, and cerebrospinal fluid, as soluble α-klotho (sαKl).
  
  
  METHODS
  We measured sαKl in 53 hemodialysis patients and 20 healthy controls to examine its role in mineral metabolism.
  
  
  RESULTS
  The sαKl level of the hemodialysis patients was 430 pg/ml (386 - 540 pg/ml, which was lower than that of healthy controls 740 pg/ml (550 - 913 pg/ml, p < 0.01). The serum sαKl level showed a positive correlation with serum phosphorus (P) (σ = 0.33, p = 0.014), while serum corrected Ca tended to be negatively correlated with sαKl (σ = -0.26, p = 0.06). Both parameters showed the same trends in healthy subjects. However, there was no significant association between serum sαKl and age (σ= 0.21, p = 0.14), intact PTH (σ = -0.08, p= 0.55), whole PTH (σ = -0.08, p = 0.59), or FGF23 (σ = -0.07, p = 0.62). Multiple regression analysis showed that P was independently associated with the serum sαKl levels (total adjusted R2 = 0.18, p = 0.02).
  
  
  CONCLUSIONS
  The sαKl level was lower in hemodialysis patients than in healthy persons. Serum P level was independently associated with the serum sαKl level.
authors.affiliation: Division of Kidney and Hypertension, Department of Internal Medicine, The Jikei University School of Medicine, Tokyo, Japan. keitaro@jikei.ac.jp
authors.forename: Keitaro
authors.initials: K
authors.lastname: Yokoyama
authors.forename: Akihiko
authors.initials: A
authors.lastname: Imura
authors.forename: Ichiro
authors.initials: I
authors.lastname: Ohkido
authors.forename: Yukio
authors.initials: Y
authors.lastname: Maruyama
authors.forename: Yuji
authors.initials: Y
authors.lastname: Yamazaki
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Jun
authors.initials: J
authors.lastname: Urae
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sekino
authors.forename: Yo-ichi
authors.initials: Y
authors.lastname: Nabeshima
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Hosoya
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002118:Calcium / Q000097:blood; D016022:Case-Control Studies; D015536:Down-Regulation; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005966:Glucuronidase / Q000097:blood*; D006801:Humans; D007564:Japan; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy*; D000090265:Klotho Proteins; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010758:Phosphorus / Q000097:blood; D012044:Regression Analysis; D006435:Renal Dialysis
chemical_list: D015415:Biomarkers; C000717427:FGF23 protein, human; D010758:Phosphorus; D000089703:Fibroblast Growth Factor-23; D005966:Glucuronidase; D000090265:Klotho Proteins; D002118:Calcium