Bioactive silica-based nanoparticles stimulate bone-forming osteoblasts, suppress bone-resorbing osteoclasts, and enhance bone mineral density in vivo

Nanomedicine. 2012 Aug;8(6):793-803. doi: 10.1016/j.nano.2011.11.003. Epub 2011 Nov 16.

Abstract

Bone is a dynamic tissue that undergoes renewal throughout life in a process whereby osteoclasts resorb worn bone and osteoblasts synthesize new bone. Imbalances in bone turnover lead to bone loss and development of osteoporosis and ultimately fracture, a debilitating condition with high morbidity and mortality. Silica is a ubiquitous biocontaminant that is considered to have high biocompatibility. The authors report that silica nanoparticles (NPs) mediate potent inhibitory effects on osteoclasts and stimulatory effects on osteoblasts in vitro. The mechanism of bioactivity is a consequence of an intrinsic capacity to antagonize activation of NF-κB, a signal transduction pathway required for osteoclastic bone resorption but inhibitory to osteoblastic bone formation. We further demonstrate that silica NPs promote a significant enhancement of bone mineral density (BMD) in mice in vivo, providing a proof of principle for the potential application of silica NPs as a pharmacological agent to enhance BMD and protect against bone fracture.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Animals
  • Bone Density / drug effects*
  • Bone Resorption / pathology
  • Bone Resorption / physiopathology*
  • Bone Resorption / prevention & control*
  • Bone Substitutes / administration & dosage
  • Female
  • Humans
  • Mice
  • Mice, Inbred C57BL
  • Nanocapsules / administration & dosage*
  • Osteoblasts / drug effects*
  • Osteoblasts / pathology
  • Osteoclasts / drug effects*
  • Osteoclasts / pathology
  • Osteogenesis / drug effects
  • Silicon Dioxide / administration & dosage*

Substances

  • Bone Substitutes
  • Nanocapsules
  • Silicon Dioxide