title: Chitosan monomer promotes tissue regeneration on dental pulp wounds.
abstract: The present study was undertaken to evaluate the applicability of chitosan monomer (D-glucosamine hydrochloride) as a pulp capping medicament. Both in vitro and in vivo experiments were carried out to study the cell metabolism and wound healing mechanisms following the application of chitomonosaccharide. After 3 days of osteoblast culture, alkaline phosphatase (ALP) activity significantly increased in the chitosan group. Reverse transcription polymerase chain reaction analysis revealed that chitosan induced an increase in the expression of ALP mRNA after 3 days and bone morphogenetic protein-2 mRNA after 7 days of osteoblast incubation. Inflammatory cytokine, interleukin (IL)-8, synthesis in fibroblasts was strongly suppressed in the medium supplemented with chitosan monomer. Histopathological effects were evaluated in rat experiments. After 1 day, inflammatory cell infiltrations were observed to be weak when compared with the application of chitosan polymer. After 3 days, a remarkable proliferation of fibroblasts was seen near the applied chitosan monomer. The inflammatory cell infiltration had almost completely disappeared. After 5 days, the fibroblastic proliferation progressed, and some odontoblastic cells appeared at the periphery of the proliferated fibroblasts. These findings indicate that the present study is the first report that chitosan monomer acts as a biocompatibility stable medicament even at the initial stage of wound healing in comparison with the application of chitosan polymer.
authors.affiliation: Division of Cariology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan.
authors.forename: Tsunenori
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Kajiro
authors.initials: K
authors.lastname: Yanagiguchi
authors.forename: Shizuka
authors.initials: S
authors.lastname: Yamada
authors.forename: Naoko
authors.initials: N
authors.lastname: Ohara
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ikeda
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Hayashi
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D000818:Animals; D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000235:genetics; D002478:Cells, Cultured; D048271:Chitosan; D003788:Dental Pulp Diseases / Q000503:physiopathology*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D012038:Regeneration; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000235:genetics
chemical_list: C525718:BMP2 protein, human; D001672:Biocompatible Materials; C525720:Bmp2 protein, rat; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D016209:Interleukin-8; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D048271:Chitosan; D000469:Alkaline Phosphatase