title: Joint immobilization inhibits spontaneous hyaline cartilage regeneration induced by a novel double-network gel implantation.
abstract: We have recently discovered that spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect in the rabbit, when we implant a novel double-network (DN) gel plug at the bottom of the defect. To clarify whether joint immobilization inhibits the spontaneous hyaline cartilage regeneration, we conducted this study with 20 rabbits. At 4 or 12 weeks after surgery, the defect in the mobile knees was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type-2 collagen, while no cartilage tissues were observed in the defect in the immobilized knees. Type-2 collagen, Aggrecan, and SOX9 mRNAs were expressed only in the mobile knees at each period. This study demonstrated that joint immobilization significantly inhibits the spontaneous hyaline cartilage regeneration induced by the DN gel implantation. This fact suggested that the mechanical environment is one of the significant factors to induce this phenomenon.
authors.affiliation: Department of Sports Medicine and Joint Reconstruction Surgery, Hokkaido University School of Medicine, Kita-15, Nishi-7, Kita-ku, Sapporo, Japan.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Arakaki
authors.forename: Nobuto
authors.initials: N
authors.lastname: Kitamura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kurokawa
authors.forename: Shin
authors.initials: S
authors.lastname: Onodera
authors.forename: Fuminori
authors.initials: F
authors.lastname: Kanaya
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Gong
authors.forename: Kazunori
authors.initials: K
authors.lastname: Yasuda
mesh_terms: D000818:Animals; D019902:Chondrocytes / Q000166:cytology; D024043:Collagen Type II / Q000378:metabolism; D004867:Equipment Design; D005260:Female; D005782:Gels; D051457:Hyaline Cartilage / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry; D007150:Immunohistochemistry / Q000379:methods; D007596:Joints / Q000473:pathology*; D008422:Materials Testing; D011509:Proteoglycans / Q000378:metabolism; D011817:Rabbits; D012038:Regeneration; D055758:SOX9 Transcription Factor / Q000378:metabolism
chemical_list: D024043:Collagen Type II; D005782:Gels; D020100:Hydrogels; D011509:Proteoglycans; D055758:SOX9 Transcription Factor