title: Compromised vertebral structural and mechanical properties associated with progressive kidney disease and the effects of traditional pharmacological interventions.
abstract: OBJECTIVE
  Patients with chronic kidney disease mineral and bone disorder (CKD-MBD) have a significantly higher vertebral and non-vertebral fracture risk than the general population. Several preclinical models have documented altered skeletal properties in long bones, but few data exist for vertebral bone. The goal of this study was to examine the effects of progressive CKD on vertebral bone structure and mechanics and to determine the effects of treatment with either bisphosphonates or anti-sclerostin antibody in groups of animals with high or low PTH.
  
  
  METHODS
  Animals with progressive kidney disease were left untreated, treated with calcium to lower PTH, zoledronic acid to lower remodeling without affecting PTH, anti-sclerostin antibody, or anti-sclerostin antibody plus calcium. Non-diseased, untreated littermates served as controls. Vertebral bone morphology (trabecular and cortical) and mechanical properties (structural and material-level) were assessed at 35 weeks of age by microCT and mechanical testing, respectively.
  
  
  RESULTS
  CKD with high PTH resulted in 6-fold higher bone formation rate, significant reductions in the amount of trabecular and cortical bone, and compromised whole bone mechanical properties in the vertebra compared to normal animals. Treatments that reduced bone remodeling were effective in normalizing vertebral structure and mechanical properties only if the treatment reduced serum PTH. Similarly, treatment with anti-sclerostin antibody was effective in enhancing bone mass and mechanical properties but only if combined with PTH-suppressive treatment.
  
  
  CONCLUSIONS
  CKD significantly altered both cortical and trabecular bone properties in the vertebra resulting in compromised mechanical properties and these changes can be normalized by interventions that involve reductions in PTH levels.
authors.affiliation: Department of Anatomy and Cell Biology, Indianapolis, IN, United States.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Newman
authors.affiliation: Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States.
authors.forename: Neal X
authors.initials: NX
authors.lastname: Chen
authors.affiliation: Department of Anatomy and Cell Biology, Indianapolis, IN, United States.
authors.forename: Eric
authors.initials: E
authors.lastname: Smith
authors.affiliation: Department of Anatomy and Cell Biology, Indianapolis, IN, United States.
authors.forename: Mark
authors.initials: M
authors.lastname: Smith
authors.affiliation: Department of Anatomy and Cell Biology, Indianapolis, IN, United States.
authors.forename: Drew
authors.initials: D
authors.lastname: Brown
authors.affiliation: Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States; Roudebush VA Medical Center, Indianapolis, IN, United States.
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Moe
authors.affiliation: Department of Anatomy and Cell Biology, Indianapolis, IN, United States; Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States. Electronic address: matallen@iupui.edu.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Allen
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology; D001847:Bone Diseases / Q000150:complications / Q000188:drug therapy* / Q000473:pathology*; D019485:Bone Morphogenetic Proteins / Q000276:immunology; D004195:Disease Models, Animal; D018450:Disease Progression; D005819:Genetic Markers / Q000276:immunology; D010281:Parathyroid Hormone / Q000037:antagonists & inhibitors; D051381:Rats; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000473:pathology*; D013131:Spine / Q000473:pathology*
chemical_list: D000906:Antibodies; D019485:Bone Morphogenetic Proteins; D005819:Genetic Markers; D010281:Parathyroid Hormone; C486031:Sost protein, rat
keywords: Anti-sclerostin antibody; CKD-MBD; Chronic kidney disease; PTH; Spine; Zoledronic acid