title: Sclerostin and Dickkopf-1 in post-menopausal renal allograft recipients.
abstract: BACKGROUND
  Age, pre-existing renal osteodistrophy, impaired renal function, and chronic use of immunosuppressive drugs are the main factors involved in the onset and development of bone metabolism disturbances and skeletal alterations occurring after renal transplantation. However, at the state of the art, no reports have analyzed the additional post-menopausal physiological mechanisms associated with the onset and development of bone complications in renal transplant recipients.
  
  
  METHODS
  We measured by means of molecular strategies (enzyme-linked immunoassay, chemiluminescence) the serum levels of Sclerostin and Dickkopf-1 (DKK1), two major antagonists of the Wnt/β-catenin pathway, and several bone resorption/formation biomarkers (N-terminal procollagen type 1, bone-specific alkaline phosphatase, and serum C-terminal telopeptides of type I collagen) in 19 post-menopausal kidney transplant patients and 12 post-menopausal chronic kidney disease patients (CKD group) matched for age and renal function.
  
  
  RESULTS
  Our results showed that the levels of both Wnt antagonists were similar in the two study groups (P=.15 and .96, respectively). Additionally, no correlation was found between Sclerostin and DKK1 serum levels in all patients included in the study (R2=0.03, P=.2). After statistical analysis, we found no differences in the bone resorption/formation biomarkers between renal transplant and CKD patients. Multivariate analysis showed that Sclerostin levels were significantly positively correlated with serum phosphorus levels (P=.008) and inversely correlated with renal function (P=.026). Surprisingly, no significant correlation was found between all the analyzed demographic and clinical parameters and DKK1.
  
  
  CONCLUSIONS
  Our study demonstrated for the first time that renal transplantation per se and immunosuppressive treatments do not represent additional factors contributing to bone metabolic/biochemical alterations in post-menopausal women. However, our results emphasized that a better preservation of the graft function could significantly slow down the progression of bone metabolic deregulations and prevent clinical bone complications.
authors.affiliation: Renal Unit, Department of Medicine, University-Hospital of Verona, Verona, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Tomei
authors.affiliation: Renal Unit, Department of Medicine, University-Hospital of Verona, Verona, Italy. Electronic address: gianluigi.zaza@univr.it.
authors.forename: G
authors.initials: G
authors.lastname: Zaza
authors.affiliation: Renal Unit, Department of Medicine, University-Hospital of Verona, Verona, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Granata
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Verona, Verona, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Gatti
authors.affiliation: Rheumatology Unit, Department of Medicine, University of Verona, Verona, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Fraccarollo
authors.affiliation: Renal, Dialysis and Transplant Unit, Department of Emergency and Transplantation, University of Bari, Bari, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Gesualdo
authors.affiliation: First Surgical Clinic, Kidney Transplantation Center, University Hospital of Verona, Verona, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Boschiero
authors.affiliation: Renal Unit, Department of Medicine, University-Hospital of Verona, Verona, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Lupo
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins / Q000097:blood*; D005260:Female; D005819:Genetic Markers; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D016030:Kidney Transplantation; D016555:Matched-Pair Analysis; D008875:Middle Aged; D010758:Phosphorus / Q000097:blood; D017698:Postmenopause; D051436:Renal Insufficiency, Chronic / Q000097:blood; D066027:Transplant Recipients
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D019485:Bone Morphogenetic Proteins; C501126:DKK1 protein, human; D005819:Genetic Markers; D036341:Intercellular Signaling Peptides and Proteins; C422903:SOST protein, human; D010758:Phosphorus