pyrophosphate and Furcation-Defects

Inorganic polyphosphate [Poly(P)] is especially prevalent in osteoblasts. We tested the hypothesis that Poly(P) stimulates osteoblastic differentiation and polyphosphate metabolism for bone formation. The osteoblast-like cell line, MC 3T3-E1, was cultured with Poly(P), and gene expression was evaluated by real-time reverse-transcription polymerase chain-reaction. Phosphatase activity and extracellular matrix mineralization were also determined. The role of Poly(P) was assessed in a beagle dog alveolar bone regeneration model. Poly(P) increased osteocalcin, osterix, bone sialoprotein, and tissue non-specific alkaline phosphatase gene expression, with a high level of end-polyphosphatase activity, resulting in low-chain-length Poly(P), inorganic pyrophosphate, and inorganic phosphate production. MC3T3-E1 cells differentiated into mature osteoblasts and showed expression of ectonucleotide pyrophosphatase phosphodiesterase 1, while mouse progressive ankylosis gene expression remained unchanged. Promotion of alveolar bone regeneration was observed in Poly(P)-treated beagle dogs. These findings suggest that Poly(P) induces osteoblastic differentiation and bone mineralization, and acts as a resource for mineralization.

Topics: 3T3 Cells; Acid Anhydride Hydrolases; Alkaline Phosphatase; Alveolar Bone Loss; Alveolar Process; Animals; Bone Regeneration; Calcification, Physiologic; Cell Differentiation; Dental Enamel Proteins; Diphosphates; Dogs; Extracellular Matrix; Furcation Defects; Integrin-Binding Sialoprotein; Male; Mice; Osteoblasts; Osteocalcin; Phenotype; Phosphates; Phosphoric Diester Hydrolases; Polyphosphates; Pyrophosphatases; Sialoglycoproteins; Sp7 Transcription Factor; Transcription Factors; Zinc Fingers