title: Strontium ranelate changes the composition and crystal structure of the biological bone-like apatite produced in osteoblast cell cultures.
abstract: We evaluate the effects of strontium ranelate on the composition and crystal structure of the biological bone-like apatite produced in osteoblast cell cultures, a system that gave us the advantage of obtaining mineral samples produced exclusively during treatment. Cells were treated with strontium ranelate at concentrations of 0.05 and 0.5 mM Sr(2+). Mineral substances were isolated and analyzed by using a combination of methods: Fourier transform infrared spectroscopy, solid-state (1)H nuclear magnetic resonance, X-ray diffraction, micro-Raman spectroscopy and energy dispersive X-ray spectroscopy. The minerals produced in all cell cultures were typical bone-like apatites. No changes occurred in the local structural order or crystal size of the minerals. However, we noticed several relevant changes in the mineral produced under 0.5 mM Sr(2+): (1) increase in type-B CO3 (2-) substitutions, which often lead to the creation of vacancies in Ca(2+) and OH(-) sites; (2) incorporation of Sr(2+) by substituting slightly less than 10 % of Ca(2+) in the apatite crystal lattice, resulting in an increase in both lattice parameters a and c; (3) change in the PO4 (3-) environments, possibly because of the expansion of the lattice; (4) the Ca/P ratio of this mineral was reduced, but its (Ca+Sr)/P ratio was the same as that of the control, indicating that its overall cation/P ratio was preserved. Thus, strontium ranelate changes the composition and crystal structure of the biological bone-like apatite produced in osteoblast cell cultures.
authors.affiliation: Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, 21941-902, Rio de Janeiro, RJ, Brazil.
authors.forename: William
authors.initials: W
authors.lastname: Querido
authors.forename: Andrea P C
authors.initials: AP
authors.lastname: Campos
authors.forename: Erlon H
authors.initials: EH
authors.lastname: Martins Ferreira
authors.forename: Rosane A S
authors.initials: RA
authors.lastname: San Gil
authors.forename: Alexandre M
authors.initials: AM
authors.lastname: Rossi
authors.forename: Marcos
authors.initials: M
authors.lastname: Farina
mesh_terms: D000818:Animals; D001031:Apatites / Q000737:chemistry*; D001842:Bone and Bones / Q000737:chemistry*; D002254:Carbonates / Q000032:analysis; D002412:Cations; D002478:Cells, Cultured; D003460:Crystallization; D051379:Mice; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects; D010710:Phosphates / Q000032:analysis; D066244:Proton Magnetic Resonance Spectroscopy; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013876:Thiophenes / Q000494:pharmacology*; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D002254:Carbonates; D002412:Cations; D010710:Phosphates; D013876:Thiophenes; C081587:strontium ranelate