Authors: Xiaohong Wang Heinz C Schröder Ute Schlossmacher Meik Neufurth Qingling Feng Bärbel DiehlSeifert Werner E G Müller
Publish Date: 2013/12/28
Volume: 94, Issue: 5, Pages: 495-509
Abstract
Caphosphate/hydroxyapatite HA crystals constitute the mineral matrix of vertebrate bones while Cacarbonate is the predominant mineral of many invertebrates like mollusks Recent results suggest that CaCO3 is also synthesized during early bone formation We demonstrate that carbonic anhydrasedriven CaCO3 formation in vitro is activated by organic extracts from the demosponge Suberites domuncula as well as by quinolinic acid one component isolated from these extracts Further results revealed that the stimulatory effect of bicarbonate HCO3 − ions on mineralization of osteoblastlike SaOS2 cells is strongly enhanced if the cells are exposed to inorganic polyphosphate polyP a linear polymer of phosphate linked by energyrich phosphodiester bonds The effect of polyP administered as polyP Ca2+ salt on HA formation was found to be amplified by addition of the carbonic anhydraseactivating sponge extract or quinolinic acid Our results support the assumption that CaCO3 deposits acting as bioseeds for Cacarbonated phosphate formation are formed as an intermediate during HA mineralization and that the carbonic anhydrasemediated formation of those deposits is under a positive–negative feedback control by bone alkaline phosphatasedependent polyP metabolism offering new targets for therapy of bone diseases/defectsW E G M is a holder of an ERC Advanced Investigator Grant 268476 BIOSILICA This work was supported by grants from the Deutsche Forschungsgemeinschaft Schr 277/103 the European Commission “BioScaffoldsCustomized Rapid Prototyping of Bioactive Scaffolds” 604036 IndustryAcademia Partnerships and Pathways “CoreShell” 286059 “MarBioTecEUCN” 268476 and “BlueGenics” 311848 and the International Human Frontier Science Program
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