title: Poly(2-acrylamido-2-methylpropanesulfonic acid) gel induces articular cartilage regeneration in vivo: comparisons of the induction ability between single- and double-network gels.
abstract: The purpose of this study was to determine the in vivo cartilage induction effect of the poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) single-network (SN) gel and poly(N,N'-dimethyl acrylamide) (PDMAAm) SN gel in comparison with that of the PAMPS/PDMAAm double-network (DN) gel. An osteochondral defect created in rabbit trochlea was treated with PAMPS/PDMAAm DN, PAMPS SN, or PDMAAm SN gel implantation or left untreated. The gel was implanted into the defect so that a 2-mm depth remained. The defects were examined by histologic and immunohistochemical evaluations, surface assessment using confocal laser scanning microscopy, and real-time polymerase chain reaction analysis at 4 weeks. Samples were quantitatively evaluated with a scoring system reported by Wayne et al. The PAMPS/PDMAAm DN gel-implanted defect was filled with the hyaline-like cartilage tissue. The PAMPS SN gel-implanted defect was filled inhomogenously with hyaline/fibrocartilage tissue. The histology score of the defect treated with PAMPS/PDMAAm DN gel was significantly higher than those treated with PAMPS and PDMAAm SN gels, and the untreated defect (p = 0.0408, p < 0.0001, and p < 0.0001, respectively) and the scores of the defect treated with PAMPS SN gel were significantly higher than those treated with PDMAAm SN gel and the untreated defect (p = 0.0026 and p = 0.0026, respectively). These results suggested that the PAMPS SN gel has an ability that can induce hyaline cartilage regeneration in vivo, but that the PDMAAm SN gel does not. The current study indicates that the chondrogenic potential of a negatively charged PAMPS gel component plays an important role in the cartilage regeneration ability of the PAMPS/PDMAAm DN gel in vivo.
authors.affiliation: Department of Sports Medicine and Joint Surgery, Graduate School of Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: Munehiro
authors.initials: M
authors.lastname: Ogawa
authors.forename: Nobuto
authors.initials: N
authors.lastname: Kitamura
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kurokawa
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Arakaki
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Jian Ping
authors.initials: JP
authors.lastname: Gong
authors.forename: Kazunori
authors.initials: K
authors.lastname: Yasuda
mesh_terms: D000178:Acrylamides / Q000737:chemistry / Q000627:therapeutic use; D053674:Aggrecans / Q000235:genetics; D000818:Animals; D002358:Cartilage, Articular / Q000187:drug effects* / Q000293:injuries / Q000378:metabolism / Q000502:physiology*; D020219:Chondrogenesis / Q000187:drug effects; D024043:Collagen Type II / Q000235:genetics; D005260:Female; D005782:Gels / Q000737:chemistry / Q000627:therapeutic use*; D005786:Gene Expression Regulation / Q000187:drug effects; D011108:Polymers / Q000737:chemistry / Q000627:therapeutic use*; D011817:Rabbits; D012038:Regeneration / Q000187:drug effects*; D055758:SOX9 Transcription Factor / Q000235:genetics; D013451:Sulfonic Acids / Q000737:chemistry / Q000627:therapeutic use*
chemical_list: D000178:Acrylamides; D053674:Aggrecans; D024043:Collagen Type II; D005782:Gels; D011108:Polymers; D055758:SOX9 Transcription Factor; D013451:Sulfonic Acids; C429790:poly(N,N-dimethylacrylamide); C077118:poly(2-acrylamido-2-methyl-1-propanesulfonic acid)