Effects of pamidronate on human alveolar osteoblasts in vitro.

Abstract

PURPOSE:

Administration of bisphosphonates has recently been associated with the development of osteonecrotic lesions of the jaw (ONJ). To elucidate the potential contributions of osteogenic cells to the development and regeneration of ONJ, we have isolated primary cells from human alveolar and long/iliac bones, and examined the effects of pamidronate on cell viability, proliferation, osteogenesis, and wound healing.

MATERIALS AND METHODS:

Primary human osteoblasts and bone marrow stromal cells were isolated from alveolar and iliac/long bone and marrow tissue. Cellular proliferation, alkaline phosphatase activity, apoptosis (terminal deoxynucleotidyl transferase dUTP nick end labeling, caspase-3, and 4,6-diamidino-2-phenylindole dihydrochloride assays) and wound healing in an in vitro scratch assay were assessed after exposure to pamidronate at a range of clinically relevant doses.

RESULTS:

Primary alveolar osteoblasts proliferated at significantly higher rates than long/iliac bone osteoblasts in vitro. Upon exposure of alveolar osteoblasts and long/iliac bone marrow stromal cells to pamidronate for more than 72 hours, we have observed significantly decreased cell viability, proliferation, osteogenesis, and in vitro wound healing at ≥6 × 10(-5) mol/L pamidronate, with the induction of apoptosis in approximately 20% of cell population.

CONCLUSIONS:

The remodeling activity of alveolar bone, indicated by higher proliferation of alveolar osteoblasts, could be negatively affected by exposure to high concentrations of pamidronate over extended periods. The absence of anabolic effects of pamidronate on alveolar osteoblasts and the induction of apoptosis in osteogenic cells could negatively affect bone balance at this site and contribute to osteonecrosis of the jaw.

• Authors: Darja Marolt, Matthew Cozin, Gordana Vunjak-Novakovic, Serge Cremers, Regina Landesberg
• Journal: Journal of oral and maxillofacial surgery : official journal of the American Association of Oral and Maxillofacial Surgeons (J Oral Maxillofac Surg) Vol. 70 Issue 5 Pg. 1081-92 (May 2012) ISSN: 1531-5053 [Electronic] United States
• PMID: 21856057 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Chemical References

• Bone Density Conservation Agents
• Diphosphonates
• Fluorescent Dyes
• Indoles
• DAPI
• Alkaline Phosphatase
• Caspase 3
• Pamidronate

Topics

• Alkaline Phosphatase (analysis, drug effects)
• Alveolar Process (cytology, drug effects)
• Apoptosis (drug effects)
• Bone Density Conservation Agents (administration & dosage, pharmacology)
• Bone Marrow Cells (drug effects)
• Bone Remodeling (drug effects)
• Caspase 3 (analysis)
• Cell Culture Techniques
• Cell Movement (drug effects)
• Cell Proliferation (drug effects)
• Cell Survival (drug effects)
• Cells, Cultured
• Diphosphonates (administration & dosage, pharmacology)
• Dose-Response Relationship, Drug
• Fluorescent Dyes
• Humans
• In Situ Nick-End Labeling
• Indoles
• Osteoblasts (drug effects)
• Osteogenesis (drug effects)
• Pamidronate
• Stromal Cells (drug effects)
• Time Factors
• Wound Healing (drug effects)