title: Matrix metalloproteinase-3 accelerates wound healing following dental pulp injury.
abstract: Matrix metalloproteinases (MMPs) are implicated in a wide range of physiological and pathological processes, including morphogenesis, wound healing, angiogenesis, inflammation, and cancer. Angiogenesis is essential for reparative dentin formation during pulp wound healing. The mechanism of angiogenesis, however, still remains unclear. We hypothesized that certain MMPs expressed during pulp wound healing may support recovery processes. To address this issue, a rat pulp injury model was established to investigate expression of MMPs during wound healing. Real-time RT-PCR analysis showed that expression MMP-3 and MMP-9 (albeit lower extent) was up-regulated at 24 and 12 hours after pulp injury, respectively, whereas expression of MMP-2 and MMP-14 was not changed. MMP-3 mRNA and protein were localized in endothelial cells and/or endothelial progenitor cells in injured pulp in vivo. In addition, MMP-3 enhanced proliferation, migration, and survival of human umbilical vein endothelial cells in vitro. Furthermore, the topical application of MMP-3 protein on the rat-injured pulp tissue in vivo induced angiogenesis and reparative dentin formation at significantly higher levels compared with controls at 24 and 72 hours after treatment, respectively. Inhibition of endogenous MMP-3 by N-Isobutyl-N-(4-methoxyphenylsulfonyl)-glycylhydroxamic acid resulted in untoward wound healing. These results provide suggestive evidence that MMP-3 released from endothelial cells and/or endothelial progenitor cells in injured pulp plays critical roles in angiogenesis and pulp wound healing.
authors.affiliation: Department of Oral Disease Research, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Aichi, Japan.
authors.forename: Li
authors.initials: L
authors.lastname: Zheng
authors.forename: Kazuharu
authors.initials: K
authors.lastname: Amano
authors.forename: Koichiro
authors.initials: K
authors.lastname: Iohara
authors.forename: Masataka
authors.initials: M
authors.lastname: Ito
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Imabayashi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Into
authors.forename: Kenji
authors.initials: K
authors.lastname: Matsushita
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakamura
authors.forename: Misako
authors.initials: M
authors.lastname: Nakashima
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002465:Cell Movement; D049109:Cell Proliferation; D002470:Cell Survival; D003782:Dental Pulp / Q000293:injuries* / Q000502:physiology; D003804:Dentin / Q000166:cytology / Q000378:metabolism; D006801:Humans; D017403:In Situ Hybridization; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D019718:Receptors, CXCR4 / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*
chemical_list: C486264:Cxcr4 protein, rat; D007527:Isoenzymes; D019718:Receptors, CXCR4; D019278:Matrix Metalloproteinase 3