Stimulation of bone healing by sustained bone morphogenetic protein 2 (BMP-2) delivery

Int J Mol Sci. 2014 May 14;15(5):8539-52. doi: 10.3390/ijms15058539.

Abstract

The aim of the study was to investigate the effect of a sustained release of bone morphogenetic protein2 (BMP-2) incorporated in a polymeric implant coating on bone healing. In vitro analysis revealed a sustained, but incomplete BMP-2 release until Day 42. For the in vivo study, the rat tibia osteotomy was stabilized either with control or BMP-2 coated wires, and the healing progress was followed by micro computed tomography (µCT), biomechanical testing and histology at Days 10, 28, 42 and 84. MicroCT showed an accelerated formation of mineralized callus, as well as remodeling and an increase of mineralized/total callus volume (p=0.021) at Day 42 in the BMP-2 group compared to the control. Histology revealed an increased callus mineralization at Days 42 and 84 (p=0.006) with reduced cartilage at Day 84 (p=0.004) in the BMP-2 group. Biomechanical stiffness was significantly higher in the BMP-2 group (p=0.045) at Day 42. In summary, bone healing was enhanced after sustained BMP-2 application compared to the control. Using the same drug delivery system, but a burst release of BMP-2, a previous published study showed a similar positive effect on bone healing. Distinct differences in the healing outcome might be explained due to the different BMP release kinetics and dosages. However, further studies are necessary to adapt the optimal release profiles to physiological mechanisms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bone Morphogenetic Protein 2 / chemistry
  • Bone Morphogenetic Protein 2 / pharmacology*
  • Bone Regeneration / drug effects
  • Bone and Bones / diagnostic imaging
  • Bone and Bones / drug effects*
  • Bone and Bones / surgery
  • Cartilage / physiology
  • Drug Carriers / chemistry*
  • Female
  • Lactic Acid / chemistry
  • Models, Animal
  • Polyesters
  • Polymers / chemistry
  • Rats
  • Rats, Sprague-Dawley
  • Time Factors
  • Tomography, X-Ray Computed
  • Wound Healing / drug effects

Substances

  • Bone Morphogenetic Protein 2
  • Drug Carriers
  • Polyesters
  • Polymers
  • Lactic Acid
  • poly(lactide)