title: Effects of teriparatide on cortical histomorphometric variables in postmenopausal women with or without prior alendronate treatment.
abstract: Cortical bone, the dominant component of the human skeleton by volume, plays a key role in protecting bones from fracture. We analyzed the cortical bone effects of teriparatide treatment in postmenopausal women with osteoporosis who had previously received long-term alendronate (ALN) therapy or were treatment naïve (TN). Tetracycline-labeled paired iliac crest biopsies obtained from 29 ALN-pretreated and 16 TN women were evaluated for dynamic histomorphometric parameters of bone formation at the periosteal, endocortical and intracortical bone compartments, before and after 24months of teriparatide treatment. At baseline, the frequency of specimens without any endocortical and periosteal tetracycline labeling, and the percentage of quiescent osteons, was higher in the ALN than the TN group. Endocortical and periosteal mineralizing surface (MS/BS%), periosteal bone formation rate (BFR/BS), mineral apposition rate (MAR) and the number of intracortical forming osteons were significantly lower in the ALN-pretreated patients than in the TN group. Following teriparatide treatment, the frequency of endocortical and periosteal unlabeled biopsies decreased; in the ALN-pretreated group the percentage of quiescent osteons decreased and, in contrast, forming and resorbing osteons were increased. Teriparatide treatment resulted in significant increases of MAR in the endocortical, and MS/BS% in the periosteal compartment in the ALN-pretreated group. Most indices of bone formation remained lower in the ALN-pretreated group compared with the TN group at study end. Endocortical wall width was increased in both ALN-pretreated and TN groups. Cortical porosity and cortical thickness were significantly increased in the ALN-pretreated group after teriparatide treatment. Our results suggest that 24months of teriparatide treatment increases cortical bone formation and cortical turnover in patients who were either TN or had previous ALN therapy.
authors.affiliation: Lilly Research Laboratories, Indianapolis, IN, USA. Electronic address: ma_linda@lilly.com.
authors.forename: Yanfei L
authors.initials: YL
authors.lastname: Ma
authors.affiliation: Lilly Research Laboratories, Indianapolis, IN, USA. Electronic address: zeng_qing_q@lilly.com.
authors.forename: Qing Q
authors.initials: QQ
authors.lastname: Zeng
authors.affiliation: Lilly Research Laboratories, Indianapolis, IN, USA. Electronic address: chiang_alan_y@lilly.com.
authors.forename: Alan Y
authors.initials: AY
authors.lastname: Chiang
authors.affiliation: Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA. Electronic address: dburr@iupui.edu.
authors.forename: David
authors.initials: D
authors.lastname: Burr
authors.affiliation: Department of Biology, Indiana University Purdue University, Indianapolis, IN, USA. Electronic address: jilili@iupui.edu.
authors.forename: Jiliang
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Graz, Austria. Electronic address: harald.dobnig@hormoninstitut-dobnig.at.
authors.forename: Harald
authors.initials: H
authors.lastname: Dobnig
authors.affiliation: Department of Internal Medicine, Division of Endocrinology and Metabolism, Medical University of Graz, Graz, Austria. Electronic address: astrid.fahrleitner@medunigraz.at.
authors.forename: Astrid
authors.initials: A
authors.lastname: Fahrleitner-Pammer
authors.affiliation: 3rd Dept. of Internal Medicine, Charles University Faculty of Medicine 1, Prague, Czech Republic. Electronic address: d.michalska@post.cz.
authors.forename: Dana
authors.initials: D
authors.lastname: Michalská
authors.affiliation: Lilly Research Centre, Windlesham, United Kingdom. Electronic address: marin_fernando@lilly.com.
authors.forename: Fernando
authors.initials: F
authors.lastname: Marin
authors.affiliation: Lilly Research Centre, Windlesham, United Kingdom. Electronic address: pavo_imre@lilly.com.
authors.forename: Imre
authors.initials: I
authors.lastname: Pavo
authors.affiliation: Institute of Rheumatology, and Charles University Faculty of Medicine 1, Prague, Czech Republic. Electronic address: endojs@seznam.cz.
authors.forename: Jan J
authors.initials: JJ
authors.lastname: Stepan
mesh_terms: D000368:Aged; D019386:Alendronate / Q000494:pharmacology / Q000627:therapeutic use*; D002113:Calcification, Physiologic / Q000187:drug effects; D005260:Female; D006801:Humans; D010012:Osteogenesis / Q000187:drug effects; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000503:physiopathology; D019379:Teriparatide / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D019379:Teriparatide; D019386:Alendronate
keywords: Alendronate; Bone biopsy; Bone formation; Cortical histomorphometry; Teriparatide