title: Enhanced bone regeneration at a segmental bone defect by controlled release of bone morphogenetic protein-2 from a biodegradable hydrogel.
abstract: The objective of this study is to investigate the feasibility of a biodegradable hydrogel of gelatin as the controlled release carrier of bone morphogenetic protein-2 (BMP-2) suitable for enhancement of bone regeneration at a segmental bone defect. Hydrogels with three different water contents were prepared through glutaraldehyde crosslinking of gelatin with an isoelectric point of 9.0 under varied reaction conditions. Segmental critical-sized defects (20 mm) were created at the ulnar bone of skeletally mature New Zealand white rabbits, and gelatin hydrogels incorporating BMP-2 (17 microg/hydrogel) were implanted into the defects. When bone regeneration was evaluated by soft x-ray observation and bone mineral density (BMD) measurement, the gelatin hydrogels incorporating BMP- 2 exhibited significantly high osteoinduction activity compared with that of free BMP-2, although the activity depended on the water content of the hydrogels. Significantly higher BMD enhancement was observed in the gelatin hydrogel with a water content of 97.8 wt% than that with the lower or higher water content. We concluded that the biodegradable gelatin hydrogel is a promising controlled release carrier of BMP-2 for bone regeneration at the segmental bone defect.
authors.affiliation: Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan.
authors.forename: Masaya
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Yoshitake
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D015519:Bone Density; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D001861:Bone Regeneration; D018786:Bone Substitutes; D003692:Delayed-Action Preparations; D005780:Gelatin; D020100:Hydrogels; D011817:Rabbits; D011859:Radiography; D016212:Transforming Growth Factor beta; D014458:Ulna Fractures / Q000000981:diagnostic imaging / Q000628:therapy*
chemical_list: D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D018786:Bone Substitutes; D003692:Delayed-Action Preparations; D020100:Hydrogels; D016212:Transforming Growth Factor beta; D005780:Gelatin