title: The effects of strontium-substituted bioactive glasses on osteoblasts and osteoclasts in vitro.
abstract: Bioactive glasses (BG) which contain strontium have the potential to combine the known bone regenerative properties of BG with the anabolic and anti-catabolic effects of strontium cations. Here we created a BG series (SiO(2)-P(2)O(5)-Na(2)O-CaO) in which 0-100% of the calcium was substituted by strontium and tested their effects on osteoblasts and osteoclasts in vitro. We show that ions released from strontium-substituted BG enhance metabolic activity in osteoblasts. They also inhibit osteoclast activity by both reducing tartrate resistant acid phosphatase activity and inhibiting resorption of calcium phosphate films in a dose-dependent manner. Additionally, osteoblasts cultured in contact with BG show increased proliferation and alkaline phosphatase activity with increasing strontium substitution, while osteoclasts adopt typical resorption morphologies. These results suggest that similarly to the osteoporosis drug strontium ranelate, strontium-substituted BG may promote an anabolic effect on osteoblasts and an anti-catabolic effect on osteoclasts. These effects, when combined with the advantages of BG such as controlled ion release and delivery versatility, may make strontium-substituted BG an effective biomaterial choice for a range of bone regeneration therapies.
authors.affiliation: Department of Materials, Imperial College, London, UK.
authors.forename: Eileen
authors.initials: E
authors.lastname: Gentleman
authors.forename: Yann C
authors.initials: YC
authors.lastname: Fredholm
authors.forename: Gavin
authors.initials: G
authors.lastname: Jell
authors.forename: Nasrin
authors.initials: N
authors.lastname: Lotfibakhshaiesh
authors.forename: Matthew D
authors.initials: MD
authors.lastname: O'Donnell
authors.forename: Robert G
authors.initials: RG
authors.lastname: Hill
authors.forename: Molly M
authors.initials: MM
authors.lastname: Stevens
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002452:Cell Count; D002454:Cell Differentiation / Q000187:drug effects; D002460:Cell Line; D004602:Elements; D005898:Glass / Q000737:chemistry*; D006801:Humans; D007477:Ions; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D008856:Microscopy, Fluorescence; D009942:Organometallic Compounds / Q000494:pharmacology*; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D010010:Osteoclasts / Q000166:cytology* / Q000187:drug effects* / Q000201:enzymology / Q000648:ultrastructure; D000071681:Tartrate-Resistant Acid Phosphatase; D013876:Thiophenes / Q000494:pharmacology*
chemical_list: D004602:Elements; D007477:Ions; D007527:Isoenzymes; D009942:Organometallic Compounds; D013876:Thiophenes; C081587:strontium ranelate; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase