title: Effects of alendronate and risedronate on bone material properties in actively forming trabecular bone surfaces.
abstract: We used Raman and Fourier transform infrared microspectroscopy (FTIRM) analysis to examine the intrinsic bone material properties at actively bone-forming trabecular surfaces in iliac crest biopsies from women with postmenopausal osteoporosis (PMO) who were treated with either alendronate (ALN) or risedronate (RIS). At eight study sites, women were identified who had postmenopausal osteoporosis (PMO), were at least 5 years postmenopause, and had been on long-term therapy (either 3-5 years or >5 years) with daily or weekly ALN or RIS. Following standard tetracycline labeling, biopsies were collected from 102 women (33 treated with ALN for 3-5 years [ALN-3], 35 with ALN for >5 years [ALN-5], 26 with RIS for 3-5 years [RIS-3], and 8 with RIS for >5 years [RIS-5]) and were analyzed at anatomical areas of similar tissue age in bone-forming areas (within the fluorescent double labels). The following outcomes were monitored and reported: mineral to matrix ratio (corresponding to ash weight), relative proteoglycan content (regulating mineralization commencement), mineral maturity (indicative of the mineral crystallite chemistry and stoichiometry, and having a direct bearing on crystallite shape and size), and the ratio of two of the major enzymatic collagen cross-links (pyridinoline/divalent). In RIS-5 there was a significant decrease in the relative proteoglycan content (-5.83% compared to ALN-5), while in both RIS-3 and RIS-5 there was significantly lower mineral maturity/crystallinity (-6.78% and -13.68% versus ALN-3 and ALN-5, respectively), and pyridinoline/divalent collagen cross-link ratio (-23.09% and -41.85% versus ALN-3 and ALN-5, respectively). The results of the present study indicate that ALN and RIS exert differential effects on the intrinsic bone material properties at actively bone-forming trabecular surfaces.
authors.affiliation: Ludwig Boltzmann Institute of Osteology, Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria.
authors.forename: Birgit
authors.initials: B
authors.lastname: Hofstetter
authors.forename: Sonja
authors.initials: S
authors.lastname: Gamsjaeger
authors.forename: Roger J
authors.initials: RJ
authors.lastname: Phipps
authors.forename: Robert R
authors.initials: RR
authors.lastname: Recker
authors.forename: Frank H
authors.initials: FH
authors.lastname: Ebetino
authors.forename: Klaus
authors.initials: K
authors.lastname: Klaushofer
authors.forename: Eleftherios P
authors.initials: EP
authors.lastname: Paschalis
mesh_terms: D000368:Aged; D019386:Alendronate / Q000494:pharmacology*; D015519:Bone Density / Q000187:drug effects*; D001842:Bone and Bones / Q000187:drug effects / Q000473:pathology*; D003430:Cross-Sectional Studies; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D006801:Humans; D000068296:Risedronic Acid; D013059:Spectrum Analysis, Raman; D013997:Time Factors
chemical_list: D000068296:Risedronic Acid; D012968:Etidronic Acid; D019386:Alendronate