title: Fetuin-A serum levels are not correlated to kidney function in long-lived subjects.
abstract: OBJECTIVE
  Serum Fetuin A has been identified as an inhibitor of ectopic calcification. It is reduced in subjects with chronic kidney disease (CKD) and it has been proposed as a potential link between CKD and the higher prevalence of arterial calcification observed in these patients. During aging both the stiffening of arterial wall due to calcification and a decline in kidney function are frequent. The aim of the study is to investigate if Fetuin A serum levels are associated with aging and with AHSG T256S polymorphism. Moreover, we aim at investigate whether serum Fetuin A is correlated to kidney function in this setting of senescence.
  
  
  METHODS
  256 health long-lived subjects (age 92 [81-100]) were recruited for the study. Serum Fetuin A was evaluated by ELISA, Cystatin C by immune-nephelometry. AHSG T256S was determinated by PCR-RFLP.
  
  
  RESULTS
  Serum Fetuin A shows a significant correlation with age (r=0.20; P=0.0048). AHSG TS and SS genotypes are associated to lower levels of serum protein (0.27 [0.19-0.29] g/L vs 0.42 [0.32-0.49] g/L; P<0.027 and 0.34 [0.25-0.41] g/L vs 0.42 [0.32-0.49] g/L; P<0.001, respectively). No significant correlation between Fetuin A and Cystatin C was observed.
  
  
  CONCLUSIONS
  Serum Fetuin A increases with age in elder individuals and subjects with the TS or SS AHSG polymorphism have lower levels of the circulating protein. No correlation with kidney function decline was observed. Other mechanisms should be investigated to explain the increase of Fetuin A with age.
authors.affiliation: Sezione di Biochimica Clinica e Medicina Molecolare, Dipartimento di Biopatologia e Biotecnologie Mediche e Forensi, Università degli Studi di Palermo, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Bellia
authors.forename: Rossella
authors.initials: R
authors.lastname: Tomaiuolo
authors.forename: Antonietta
authors.initials: A
authors.lastname: Caruso
authors.forename: Bruna Lo
authors.initials: BL
authors.lastname: Sasso
authors.forename: Federica
authors.initials: F
authors.lastname: Zarrilli
authors.forename: Ciriaco
authors.initials: C
authors.lastname: Carru
authors.forename: Maria
authors.initials: M
authors.lastname: Deiana
authors.forename: Angelo
authors.initials: A
authors.lastname: Zinellu
authors.forename: Sara
authors.initials: S
authors.lastname: Pinna
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Castaldo
authors.forename: Luca
authors.initials: L
authors.lastname: Deiana
authors.forename: Marcello
authors.initials: M
authors.lastname: Ciaccio
mesh_terms: D000369:Aged, 80 and over; D000375:Aging / Q000097:blood / Q000235:genetics*; D002114:Calcinosis / Q000097:blood / Q000150:complications / Q000235:genetics*; D055316:Cystatin C / Q000097:blood / Q000235:genetics; D005260:Female; D015870:Gene Expression; D006801:Humans; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000235:genetics*; D007677:Kidney Function Tests; D008297:Male; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D060749:alpha-2-HS-Glycoprotein / Q000032:analysis / Q000235:genetics*
chemical_list: D055316:Cystatin C; D060749:alpha-2-HS-Glycoprotein