title: Expression of nAG and Prod-1 in Terminal Phalanx Amputation Stumps of Adult Mice: An Experimental Model of Bone Regeneration in Higher Vertebrates.
abstract: BACKGROUND
  nAG and Prod-1 are proteins responsible for the regeneration of completely amputated limbs in salamanders (which are lower vertebrates). The purpose of this study was to introduce an experimental distal phalanx amputation model in mice (which are higher vertebrates) in which nAG and Prod-1 are expressed in the amputation stumps.
  
  
  METHODS
  Sixteen mice with amputation of the distal two-thirds of the distal phalanx were used. One hind limb was used and the central three digits were amputated. Injection of nAG and Prod-1 plasmids was performed in the footpad twice weekly in experimental mice (n = 8), and injection of solution only (without the plasmids) was performed twice weekly in control mice (n = 8).
  
  
  RESULTS
  nAG and Prod-1 were expressed in experimental stumps only. This expression results in quicker and more mature bone regeneration in experimental animals, and this was shown using histology and immune stains to osteocalcin (an osteoblast marker). Finally, quantitative mRNA showed a 21-fold increase of osteocalcin in experimental stumps compared with control stumps, and this was statistically significant.
  
  
  CONCLUSIONS
  Injection of nAG and Prod-1 into the footpad will result in their expression in the distal amputation stumps, and this will enhance bone regeneration in the model described.
authors.affiliation: Riyadh, Saudi Arabia From the Department of Surgery, the College of Medicine Research Center, and the Department of Pathology, King Saud University.
authors.forename: Mohammad M
authors.initials: MM
authors.lastname: Al-Qattan
authors.forename: Mervat M
authors.initials: MM
authors.lastname: Abd-Alwahed
authors.forename: Maha
authors.initials: M
authors.lastname: Arafah
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Al-Qattan
authors.forename: Medhat K
authors.initials: MK
authors.lastname: Shier
mesh_terms: D000671:Amputation, Surgical / Q000379:methods; D000672:Amputation Stumps / Q000473:pathology*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001707:Biopsy, Needle; D001861:Bone Regeneration / Q000187:drug effects*; D019362:Cytochrome P-450 CYP2B1 / Q000378:metabolism / Q000494:pharmacology*; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D051379:Mice; D008815:Mice, Inbred Strains; D011506:Proteins / Q000378:metabolism / Q000494:pharmacology*; D012313:RNA / Q000378:metabolism; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D011506:Proteins; D012313:RNA; D019362:Cytochrome P-450 CYP2B1