title: Basic fibroblast growth factor induces the expression of matrix metalloproteinase-3 in human periodontal ligament cells through the MEK2 mitogen-activated protein kinase pathway.
abstract: Basic fibroblast growth factor (bFGF, FGF-2) is one of the potent mitogens for periodontal ligament (PDL) cells. However, the role of bFGF on the matrix metalloproteinase-3 (MMP-3) expression in PDL cells is unknown. In this study, the effect of bFGF on MMP-3 expression in PDL cells and the mechanism of this process were examined. Human PDL cells were exposed to bFGF at various concentrations (0.01-10 ng/ml) in monolayer cultures. bFGF increased [3H]thymidine incorporation and suppressed proteoglycan synthesis concentration-dependently. However, similar concentration ranges of bFGF increased the release of the cell-associated proteoglycans into the medium. Furthermore, bFGF increased MMP-3 mRNA levels concentration-dependently as examined by reverse transcription-polymerase chain reaction (RT-PCR). Induction of MMP-3 after the stimulation with bFGF was observed as early as 12 h with maximal at 24 h. Thereafter, the MMP-3 mRNA level gradually decreased until 72 h. Cycloheximide blocked the induction of MMP-3 by bFGF, indicating the requirement of de novo protein synthesis for this stimulation. Furthermore, MMP-3 expression induced by bFGF was abrogated by U0126, a specific inhibitor of MEK1/2 and ERK1/2 in mitogen-activated protein (MAP) kinase pathway, not by PD98059, a specific inhibitor of MEK1. In addition, bFGF up-regulated the phosphorylated ERK1/2 in 5 min with the maximal at 20 min as examined by Western blotting, and U0126 inhibited the ERK1/2 phosphorylation induced by bFGF. These findings suggest that bFGF induces MMP-3 expression in PDL cells through the activation of the MEK2 in MAP kinase pathway. bFGF stimulation on MMP-3 synthesis may be involved in the control of the cell-associated proteoglycans in PDL cells during periodontal regeneration and degradation.
authors.affiliation: Department of Preventive Dentistry, Faculty of Dentistry, Hiroshima University, Hiroshima, Japan. atsushi@hiroshima-u.ac.jp
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shimazu
authors.forename: Masayuki
authors.initials: M
authors.lastname: Morishita
mesh_terms: D000704:Analysis of Variance; D002070:Butadienes / Q000494:pharmacology; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D018929:Cell Culture Techniques; D003513:Cycloheximide / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006801:Humans; D048370:MAP Kinase Kinase 2; D019278:Matrix Metalloproteinase 3 / Q000187:drug effects* / Q000235:genetics; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009570:Nitriles / Q000494:pharmacology; D010513:Periodontal Ligament / Q000201:enzymology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D011509:Proteoglycans / Q000037:antagonists & inhibitors / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D002070:Butadienes; D004791:Enzyme Inhibitors; D005419:Flavonoids; D009570:Nitriles; D011500:Protein Synthesis Inhibitors; D011509:Proteoglycans; D012333:RNA, Messenger; C113580:U 0126; D016222:Fibroblast Growth Factor 2; D003513:Cycloheximide; C482128:MAP2K2 protein, human; D011505:Protein-Tyrosine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048370:MAP Kinase Kinase 2; D020929:Mitogen-Activated Protein Kinase Kinases; D019278:Matrix Metalloproteinase 3; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D013936:Thymidine