title: Sustained release of OP-1 and antibiotics in treatment of femoral defects in male rats.
abstract: Osteogenic proteins (OP-1) promote osteoinduction. Formation of new bone growth in patients receiving OP-1 is not consistent, and is possibly due to the short half-life of the drug. In order to test the capacity of OP-1 to consistently produce bone in a fracture model, a drug delivery system was developed to prolong the action of OP-1. Fifteen Sprague Dawley male rats were randomly divided into three equal groups; Animals in group 1 served as control. Animals in groups 2 and 3 had a 5mm defect created in the left femur using a number six dental burr and a drug delivery capsule (TCPL) containing either antibiotic alone (sham) or antibiotic +OP-1. Body weights, blood, and X-rays were taken weekly. Femurs and organs were harvested 30 days post-op, and processed for histomorphometry. Data was analyzed using ANOVA and significant difference between the groups was determined using Student Newman Kuels (p < 0.05). The results showed complete bone healing in the OP-1 group with an evident callus formation. The osteoid tissue exhibited a proliferation of osteoblasts, which differentiated from the vascularized mesenchymal tissue. The complete bone healing using OP-1 sharply contrasted sham treatment, where an obvious injury was still seen at 30 days. Histologically sham animals exhibited the early stage of repair with evidence of blood clotting and mesenchyme with early formation of osteoblasts. Overall, OP-1 delivered in a sustained manner for 30 days caused increased bone formation in a defect model.
authors.affiliation: The University of Mississippi Medical Center, Jackson, MS 39216, USA.
authors.forename: Sergey
authors.initials: S
authors.lastname: Dzugan
authors.forename: Chris
authors.initials: C
authors.lastname: Galjour
authors.forename: Joe
authors.initials: J
authors.lastname: Conflitti
authors.forename: Ham
authors.initials: H
authors.lastname: Benghuzzi
authors.forename: Michelle
authors.initials: M
authors.lastname: Tucci
authors.forename: George
authors.initials: G
authors.lastname: Russell
authors.forename: Audrey
authors.initials: A
authors.lastname: Tsao
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D004338:Drug Combinations; D004343:Drug Implants / Q000008:administration & dosage; D005264:Femoral Fractures / Q000150:complications / Q000188:drug therapy* / Q000473:pathology*; D017102:Fracture Healing / Q000187:drug effects*; D008297:Male; D010000:Osteitis / Q000209:etiology / Q000473:pathology* / Q000517:prevention & control*; D010012:Osteogenesis / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000008:administration & dosage*; D016896:Treatment Outcome; D014640:Vancomycin / Q000008:administration & dosage*
chemical_list: D000900:Anti-Bacterial Agents; C525821:Bmp7 protein, rat; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D004338:Drug Combinations; D004343:Drug Implants; D016212:Transforming Growth Factor beta; D014640:Vancomycin