title: Localization of vascular endothelial growth factor during the early stages of osteochondral regeneration using a bioabsorbable synthetic polymer scaffold.
abstract: Vascular endothelial growth factor (VEGF) plays a critical role in chondrogenic differentiation in the growth plate of the epiphysis. This function is necessary for chondrocyte survival in cartilage development. We investigated the localization of VEGF in the osteochondral regeneration process using a bioabsorbable polymer scaffold. Osteochondral defects (5 mm in diameter and 5 mm in depth) were made on the femoral condyle of forty-eight skeletally mature female Japanese white rabbits. In total, twenty-four defects were filled with poly(DL-lactide-co-glycolide) scaffolds and the others were left untreated. The regeneration process was investigated macroscopically, histologically, immunohistochemically, and by gene expression analysis. In the early stages of osteochondral regeneration, bone ingrowth was observed in the deep zone of the scaffold with continuous VEGF expression; cartilage regeneration was observed in the superficial zone of the scaffold with decreased VEGF expression. In contrast, when the defect was left untreated, VEGF localization was observed throughout the entire defect area, and cartilage regeneration at the articular surface was delayed. We conclude that decrease in localization of VEGF at the articular surface in the postoperative early stage is closely related to the progression of cartilage regeneration in osteochondral defects.
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan. qqty3nf9@vanilla.ocn.ne.jp
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Sakata
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kokubu
authors.forename: Issei
authors.initials: I
authors.lastname: Nagura
authors.forename: Narikazu
authors.initials: N
authors.lastname: Toyokawa
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Inui
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Fujioka
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kurosaka
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D002356:Cartilage / Q000502:physiology*; D005260:Female; D005269:Femur / Q000601:surgery; D007150:Immunohistochemistry; D011098:Polyglactin 910; D011817:Rabbits; D060888:Real-Time Polymerase Chain Reaction; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis* / Q000235:genetics / Q000502:physiology
chemical_list: D042461:Vascular Endothelial Growth Factor A; D011098:Polyglactin 910