title: Osteogenic growth peptide modulates fracture callus structural and mechanical properties.
abstract: The osteogenic growth peptide (OGP) is a key factor in the mechanism of the systemic osteogenic response to local bone marrow injury. Recent histologic studies have shown that OGP enhances fracture healing in experimental animals. To assess the effect of systemically administered OGP on the biomechanical and quantitative structural properties of the fracture callus, the present study used an integrated approach to evaluate the early stages (up to 4 weeks) of healing of unstable mid-femoral fractures in rats, which included biomechanical, micro-computed tomographic (microCT) and histomorphometric measurements. During the first 3 weeks after fracture, all the quantitative microCT parameters increased in the OGP- and vehicle-treated animals alike. After 4 weeks, the volume of total callus, bony callus, and newly formed bone was approximately 20% higher in animals administered with OGP, consequent to a decrease in the controls. The 4-week total connectivity was 46% higher in the OGP-treated animals. At this time, bridging between the fracture ends by newly formed bone was observed predominantly in the OGP-treated fractures. After 3 and 4 weeks, the OGP-treated animals showed higher biomechanical toughness of the fracture callus as compared to the PBS controls. Significant correlations between structural and biomechanical parameters were restricted to the OGP-treated rats. These data imply that the osteogenic effect of OGP results in enhanced bridging across the fracture gap and consequently improved function of the fracture callus. Therefore, OGP and/or its derivatives are suggested as a potential therapy for the acceleration of bone regeneration in instances of fracture repair and perhaps other bone injuries.
authors.affiliation: Bone Laboratory, Institute of Dental Sciences, Faculty of Dental Medicine, The Hebrew University of Jerusalem, Israel.
authors.forename: Yankel
authors.initials: Y
authors.lastname: Gabet
authors.forename: Ralph
authors.initials: R
authors.lastname: Müller
authors.forename: Eran
authors.initials: E
authors.lastname: Regev
authors.forename: Jona
authors.initials: J
authors.lastname: Sela
authors.forename: Arie
authors.initials: A
authors.lastname: Shteyer
authors.forename: Kristy
authors.initials: K
authors.lastname: Salisbury
authors.forename: Michael
authors.initials: M
authors.lastname: Chorev
authors.forename: Itai
authors.initials: I
authors.lastname: Bab
mesh_terms: D000818:Animals; D002146:Bony Callus / Q000187:drug effects* / Q000473:pathology / Q000503:physiopathology; D005269:Femur / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D050723:Fractures, Bone / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D006657:Histones; D036341:Intercellular Signaling Peptides and Proteins / Q000627:therapeutic use*; D008297:Male; D051381:Rats; D013718:Tensile Strength; D014057:Tomography, X-Ray Computed; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D006657:Histones; D036341:Intercellular Signaling Peptides and Proteins; C074533:osteogenic growth peptide