title: Bone mineral and collagen quality in iliac crest biopsies of patients given teriparatide: new results from the fracture prevention trial.
abstract: BACKGROUND
  Evidence suggests that both bone mineral density and bone quality should be taken into account when assessing bone strength and fracture risk. Bone quality is a multifactor entity, of which bone architecture and material properties are two important components. Matrix mineralization, hydroxyapatite characteristics, and collagen cross-link ratio are key determinants of material properties. Fourier transform infrared imaging (FTIRI) yields data on these characteristics from bone sections.
  
  
  OBJECTIVE
  We sought to determine collagen cross-link ratios and matrix mineralization of bone from patients randomized to teriparatide [recombinant human PTH (1-34)] treatment using FTIRI.
  
  
  METHODS
  The Fracture Prevention Trial was randomized, double blind, and placebo-controlled.
  
  
  METHODS
  The trial was conducted at global clinical research centers.
  
  
  METHODS
  Patients consisted of postmenopausal women with osteoporosis.
  
  
  METHODS
  Patients were randomized to receive daily sc injections of placebo (n = 12) or 20 microg (n = 13) or 40 microg (n = 13) teriparatide. Biopsies were obtained after 12 months of treatment or at the end of treatment (range, 19-24 months for end of treatment paired biopsies).
  
  
  METHODS
  Biopsies were analyzed by FTIRI to determine the matrix mineralization (mineral to matrix), mineral crystallinity, and collagen cross-link ratio (pyridinoline/dehydrodihydroxylysinonorleucine) with a spatial resolution of approximately 6.3 microm.
  
  
  RESULTS
  Patients administered teriparatide 20 and 40 microg/d exhibited significantly lower matrix mineralization, mineral crystallinity, and collagen cross-link ratio when compared with placebo.
  
  
  CONCLUSIONS
  These findings indicate that the bone-forming effect of teriparatide results in bone with a molecular profile reminiscent of younger bone.
authors.affiliation: Mineralized Tissue Section, Research Division, The Hospital for Special Surgery, New York, New York 10021, USA.
authors.forename: Eleftherios P
authors.initials: EP
authors.lastname: Paschalis
authors.forename: Emmett V
authors.initials: EV
authors.lastname: Glass
authors.forename: David W
authors.initials: DW
authors.lastname: Donley
authors.forename: Erik F
authors.initials: EF
authors.lastname: Eriksen
mesh_terms: D000368:Aged; D001706:Biopsy; D015519:Bone Density / Q000187:drug effects*; D002113:Calcification, Physiologic / Q000187:drug effects; D003094:Collagen / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000378:metabolism; D005260:Female; D050723:Fractures, Bone / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D006801:Humans; D007085:Ilium / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D019379:Teriparatide / Q000008:administration & dosage*
chemical_list: D003432:Cross-Linking Reagents; D019379:Teriparatide; D003094:Collagen